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/timer.h>
19 #include <linux/vmalloc.h>
20 #include <linux/interrupt.h>
21 #include <linux/bitops.h>
22 #include <linux/mutex.h>
23 #include <linux/workqueue.h>
24 #include <linux/highmem.h>
25 #include <linux/firmware.h>
26 #include <linux/slab.h>
27 #include <linux/sched.h>
28 #include <linux/file.h>
29 #include <linux/list.h>
31 #include <linux/async.h>
33 #include <linux/suspend.h>
34 #include <linux/syscore_ops.h>
35 #include <linux/reboot.h>
36 #include <linux/security.h>
39 #include <generated/utsrelease.h>
45 MODULE_AUTHOR("Manuel Estrada Sainz");
46 MODULE_DESCRIPTION("Multi purpose firmware loading support");
47 MODULE_LICENSE("GPL");
49 struct firmware_cache {
50 /* firmware_buf instance will be added into the below list */
52 struct list_head head;
55 #ifdef CONFIG_FW_CACHE
57 * Names of firmware images which have been cached successfully
58 * will be added into the below list so that device uncache
59 * helper can trace which firmware images have been cached
63 struct list_head fw_names;
65 struct delayed_work work;
67 struct notifier_block pm_notify;
71 struct fw_cache_entry {
72 struct list_head list;
81 static inline struct fw_priv *to_fw_priv(struct kref *ref)
83 return container_of(ref, struct fw_priv, ref);
86 #define FW_LOADER_NO_CACHE 0
87 #define FW_LOADER_START_CACHE 1
89 /* fw_lock could be moved to 'struct fw_sysfs' but since it is just
90 * guarding for corner cases a global lock should be OK */
91 DEFINE_MUTEX(fw_lock);
93 static struct firmware_cache fw_cache;
95 /* Builtin firmware support */
97 #ifdef CONFIG_FW_LOADER
99 extern struct builtin_fw __start_builtin_fw[];
100 extern struct builtin_fw __end_builtin_fw[];
102 static void fw_copy_to_prealloc_buf(struct firmware *fw,
103 void *buf, size_t size)
105 if (!buf || size < fw->size)
107 memcpy(buf, fw->data, fw->size);
110 static bool fw_get_builtin_firmware(struct firmware *fw, const char *name,
111 void *buf, size_t size)
113 struct builtin_fw *b_fw;
115 for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
116 if (strcmp(name, b_fw->name) == 0) {
117 fw->size = b_fw->size;
118 fw->data = b_fw->data;
119 fw_copy_to_prealloc_buf(fw, buf, size);
128 static bool fw_is_builtin_firmware(const struct firmware *fw)
130 struct builtin_fw *b_fw;
132 for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
133 if (fw->data == b_fw->data)
139 #else /* Module case - no builtin firmware support */
141 static inline bool fw_get_builtin_firmware(struct firmware *fw,
142 const char *name, void *buf,
148 static inline bool fw_is_builtin_firmware(const struct firmware *fw)
154 static void fw_state_init(struct fw_priv *fw_priv)
156 struct fw_state *fw_st = &fw_priv->fw_st;
158 init_completion(&fw_st->completion);
159 fw_st->status = FW_STATUS_UNKNOWN;
162 static inline int fw_state_wait(struct fw_priv *fw_priv)
164 return __fw_state_wait_common(fw_priv, MAX_SCHEDULE_TIMEOUT);
167 static int fw_cache_piggyback_on_request(const char *name);
169 static struct fw_priv *__allocate_fw_priv(const char *fw_name,
170 struct firmware_cache *fwc,
176 struct fw_priv *fw_priv;
178 /* For a partial read, the buffer must be preallocated. */
179 if ((opt_flags & FW_OPT_PARTIAL) && !dbuf)
182 /* Only partial reads are allowed to use an offset. */
183 if (offset != 0 && !(opt_flags & FW_OPT_PARTIAL))
186 fw_priv = kzalloc(sizeof(*fw_priv), GFP_ATOMIC);
190 fw_priv->fw_name = kstrdup_const(fw_name, GFP_ATOMIC);
191 if (!fw_priv->fw_name) {
196 kref_init(&fw_priv->ref);
198 fw_priv->data = dbuf;
199 fw_priv->allocated_size = size;
200 fw_priv->offset = offset;
201 fw_priv->opt_flags = opt_flags;
202 fw_state_init(fw_priv);
203 #ifdef CONFIG_FW_LOADER_USER_HELPER
204 INIT_LIST_HEAD(&fw_priv->pending_list);
207 pr_debug("%s: fw-%s fw_priv=%p\n", __func__, fw_name, fw_priv);
212 static struct fw_priv *__lookup_fw_priv(const char *fw_name)
215 struct firmware_cache *fwc = &fw_cache;
217 list_for_each_entry(tmp, &fwc->head, list)
218 if (!strcmp(tmp->fw_name, fw_name))
223 /* Returns 1 for batching firmware requests with the same name */
224 static int alloc_lookup_fw_priv(const char *fw_name,
225 struct firmware_cache *fwc,
226 struct fw_priv **fw_priv,
234 spin_lock(&fwc->lock);
236 * Do not merge requests that are marked to be non-cached or
237 * are performing partial reads.
239 if (!(opt_flags & (FW_OPT_NOCACHE | FW_OPT_PARTIAL))) {
240 tmp = __lookup_fw_priv(fw_name);
243 spin_unlock(&fwc->lock);
245 pr_debug("batched request - sharing the same struct fw_priv and lookup for multiple requests\n");
250 tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size, offset, opt_flags);
252 INIT_LIST_HEAD(&tmp->list);
253 if (!(opt_flags & FW_OPT_NOCACHE))
254 list_add(&tmp->list, &fwc->head);
256 spin_unlock(&fwc->lock);
260 return tmp ? 0 : -ENOMEM;
263 static void __free_fw_priv(struct kref *ref)
264 __releases(&fwc->lock)
266 struct fw_priv *fw_priv = to_fw_priv(ref);
267 struct firmware_cache *fwc = fw_priv->fwc;
269 pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
270 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
271 (unsigned int)fw_priv->size);
273 list_del(&fw_priv->list);
274 spin_unlock(&fwc->lock);
276 if (fw_is_paged_buf(fw_priv))
277 fw_free_paged_buf(fw_priv);
278 else if (!fw_priv->allocated_size)
279 vfree(fw_priv->data);
281 kfree_const(fw_priv->fw_name);
285 static void free_fw_priv(struct fw_priv *fw_priv)
287 struct firmware_cache *fwc = fw_priv->fwc;
288 spin_lock(&fwc->lock);
289 if (!kref_put(&fw_priv->ref, __free_fw_priv))
290 spin_unlock(&fwc->lock);
293 #ifdef CONFIG_FW_LOADER_PAGED_BUF
294 bool fw_is_paged_buf(struct fw_priv *fw_priv)
296 return fw_priv->is_paged_buf;
299 void fw_free_paged_buf(struct fw_priv *fw_priv)
306 vunmap(fw_priv->data);
308 for (i = 0; i < fw_priv->nr_pages; i++)
309 __free_page(fw_priv->pages[i]);
310 kvfree(fw_priv->pages);
311 fw_priv->pages = NULL;
312 fw_priv->page_array_size = 0;
313 fw_priv->nr_pages = 0;
316 int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed)
318 /* If the array of pages is too small, grow it */
319 if (fw_priv->page_array_size < pages_needed) {
320 int new_array_size = max(pages_needed,
321 fw_priv->page_array_size * 2);
322 struct page **new_pages;
324 new_pages = kvmalloc_array(new_array_size, sizeof(void *),
328 memcpy(new_pages, fw_priv->pages,
329 fw_priv->page_array_size * sizeof(void *));
330 memset(&new_pages[fw_priv->page_array_size], 0, sizeof(void *) *
331 (new_array_size - fw_priv->page_array_size));
332 kvfree(fw_priv->pages);
333 fw_priv->pages = new_pages;
334 fw_priv->page_array_size = new_array_size;
337 while (fw_priv->nr_pages < pages_needed) {
338 fw_priv->pages[fw_priv->nr_pages] =
339 alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
341 if (!fw_priv->pages[fw_priv->nr_pages])
349 int fw_map_paged_buf(struct fw_priv *fw_priv)
351 /* one pages buffer should be mapped/unmapped only once */
355 vunmap(fw_priv->data);
356 fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages, 0,
366 * XZ-compressed firmware support
368 #ifdef CONFIG_FW_LOADER_COMPRESS
369 /* show an error and return the standard error code */
370 static int fw_decompress_xz_error(struct device *dev, enum xz_ret xz_ret)
372 if (xz_ret != XZ_STREAM_END) {
373 dev_warn(dev, "xz decompression failed (xz_ret=%d)\n", xz_ret);
374 return xz_ret == XZ_MEM_ERROR ? -ENOMEM : -EINVAL;
379 /* single-shot decompression onto the pre-allocated buffer */
380 static int fw_decompress_xz_single(struct device *dev, struct fw_priv *fw_priv,
381 size_t in_size, const void *in_buffer)
383 struct xz_dec *xz_dec;
384 struct xz_buf xz_buf;
387 xz_dec = xz_dec_init(XZ_SINGLE, (u32)-1);
391 xz_buf.in_size = in_size;
392 xz_buf.in = in_buffer;
394 xz_buf.out_size = fw_priv->allocated_size;
395 xz_buf.out = fw_priv->data;
398 xz_ret = xz_dec_run(xz_dec, &xz_buf);
401 fw_priv->size = xz_buf.out_pos;
402 return fw_decompress_xz_error(dev, xz_ret);
405 /* decompression on paged buffer and map it */
406 static int fw_decompress_xz_pages(struct device *dev, struct fw_priv *fw_priv,
407 size_t in_size, const void *in_buffer)
409 struct xz_dec *xz_dec;
410 struct xz_buf xz_buf;
415 xz_dec = xz_dec_init(XZ_DYNALLOC, (u32)-1);
419 xz_buf.in_size = in_size;
420 xz_buf.in = in_buffer;
423 fw_priv->is_paged_buf = true;
426 if (fw_grow_paged_buf(fw_priv, fw_priv->nr_pages + 1)) {
431 /* decompress onto the new allocated page */
432 page = fw_priv->pages[fw_priv->nr_pages - 1];
433 xz_buf.out = kmap(page);
435 xz_buf.out_size = PAGE_SIZE;
436 xz_ret = xz_dec_run(xz_dec, &xz_buf);
438 fw_priv->size += xz_buf.out_pos;
439 /* partial decompression means either end or error */
440 if (xz_buf.out_pos != PAGE_SIZE)
442 } while (xz_ret == XZ_OK);
444 err = fw_decompress_xz_error(dev, xz_ret);
446 err = fw_map_paged_buf(fw_priv);
453 static int fw_decompress_xz(struct device *dev, struct fw_priv *fw_priv,
454 size_t in_size, const void *in_buffer)
456 /* if the buffer is pre-allocated, we can perform in single-shot mode */
458 return fw_decompress_xz_single(dev, fw_priv, in_size, in_buffer);
460 return fw_decompress_xz_pages(dev, fw_priv, in_size, in_buffer);
462 #endif /* CONFIG_FW_LOADER_COMPRESS */
464 /* direct firmware loading support */
465 static char fw_path_para[256];
466 static const char * const fw_path[] = {
468 "/lib/firmware/updates/" UTS_RELEASE,
469 "/lib/firmware/updates",
470 "/lib/firmware/" UTS_RELEASE,
475 * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
476 * from kernel command line because firmware_class is generally built in
477 * kernel instead of module.
479 module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
480 MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
483 fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv,
485 int (*decompress)(struct device *dev,
486 struct fw_priv *fw_priv,
488 const void *in_buffer))
494 size_t msize = INT_MAX;
497 /* Already populated data member means we're loading into a buffer */
498 if (!decompress && fw_priv->data) {
499 buffer = fw_priv->data;
500 msize = fw_priv->allocated_size;
507 for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
508 size_t file_size = 0;
509 size_t *file_size_ptr = NULL;
511 /* skip the unset customized path */
515 len = snprintf(path, PATH_MAX, "%s/%s%s",
516 fw_path[i], fw_priv->fw_name, suffix);
517 if (len >= PATH_MAX) {
525 * The total file size is only examined when doing a partial
526 * read; the "full read" case needs to fail if the whole
527 * firmware was not completely loaded.
529 if ((fw_priv->opt_flags & FW_OPT_PARTIAL) && buffer)
530 file_size_ptr = &file_size;
532 /* load firmware files from the mount namespace of init */
533 rc = kernel_read_file_from_path_initns(path, fw_priv->offset,
539 dev_warn(device, "loading %s failed with error %d\n",
542 dev_dbg(device, "loading %s failed for no such file or directory.\n",
549 dev_dbg(device, "Loading firmware from %s\n", path);
551 dev_dbg(device, "f/w decompressing %s\n",
553 rc = decompress(device, fw_priv, size, buffer);
554 /* discard the superfluous original content */
558 fw_free_paged_buf(fw_priv);
562 dev_dbg(device, "direct-loading %s\n",
565 fw_priv->data = buffer;
566 fw_priv->size = size;
568 fw_state_done(fw_priv);
576 /* firmware holds the ownership of pages */
577 static void firmware_free_data(const struct firmware *fw)
579 /* Loaded directly? */
584 free_fw_priv(fw->priv);
587 /* store the pages buffer info firmware from buf */
588 static void fw_set_page_data(struct fw_priv *fw_priv, struct firmware *fw)
591 fw->size = fw_priv->size;
592 fw->data = fw_priv->data;
594 pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
595 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
596 (unsigned int)fw_priv->size);
599 #ifdef CONFIG_FW_CACHE
600 static void fw_name_devm_release(struct device *dev, void *res)
602 struct fw_name_devm *fwn = res;
604 if (fwn->magic == (unsigned long)&fw_cache)
605 pr_debug("%s: fw_name-%s devm-%p released\n",
606 __func__, fwn->name, res);
607 kfree_const(fwn->name);
610 static int fw_devm_match(struct device *dev, void *res,
613 struct fw_name_devm *fwn = res;
615 return (fwn->magic == (unsigned long)&fw_cache) &&
616 !strcmp(fwn->name, match_data);
619 static struct fw_name_devm *fw_find_devm_name(struct device *dev,
622 struct fw_name_devm *fwn;
624 fwn = devres_find(dev, fw_name_devm_release,
625 fw_devm_match, (void *)name);
629 static bool fw_cache_is_setup(struct device *dev, const char *name)
631 struct fw_name_devm *fwn;
633 fwn = fw_find_devm_name(dev, name);
640 /* add firmware name into devres list */
641 static int fw_add_devm_name(struct device *dev, const char *name)
643 struct fw_name_devm *fwn;
645 if (fw_cache_is_setup(dev, name))
648 fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm),
652 fwn->name = kstrdup_const(name, GFP_KERNEL);
658 fwn->magic = (unsigned long)&fw_cache;
659 devres_add(dev, fwn);
664 static bool fw_cache_is_setup(struct device *dev, const char *name)
669 static int fw_add_devm_name(struct device *dev, const char *name)
675 int assign_fw(struct firmware *fw, struct device *device)
677 struct fw_priv *fw_priv = fw->priv;
680 mutex_lock(&fw_lock);
681 if (!fw_priv->size || fw_state_is_aborted(fw_priv)) {
682 mutex_unlock(&fw_lock);
687 * add firmware name into devres list so that we can auto cache
688 * and uncache firmware for device.
690 * device may has been deleted already, but the problem
691 * should be fixed in devres or driver core.
693 /* don't cache firmware handled without uevent */
694 if (device && (fw_priv->opt_flags & FW_OPT_UEVENT) &&
695 !(fw_priv->opt_flags & FW_OPT_NOCACHE)) {
696 ret = fw_add_devm_name(device, fw_priv->fw_name);
698 mutex_unlock(&fw_lock);
704 * After caching firmware image is started, let it piggyback
705 * on request firmware.
707 if (!(fw_priv->opt_flags & FW_OPT_NOCACHE) &&
708 fw_priv->fwc->state == FW_LOADER_START_CACHE) {
709 if (fw_cache_piggyback_on_request(fw_priv->fw_name))
710 kref_get(&fw_priv->ref);
713 /* pass the pages buffer to driver at the last minute */
714 fw_set_page_data(fw_priv, fw);
715 mutex_unlock(&fw_lock);
719 /* prepare firmware and firmware_buf structs;
720 * return 0 if a firmware is already assigned, 1 if need to load one,
721 * or a negative error code
724 _request_firmware_prepare(struct firmware **firmware_p, const char *name,
725 struct device *device, void *dbuf, size_t size,
726 size_t offset, u32 opt_flags)
728 struct firmware *firmware;
729 struct fw_priv *fw_priv;
732 *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
734 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
739 if (fw_get_builtin_firmware(firmware, name, dbuf, size)) {
740 dev_dbg(device, "using built-in %s\n", name);
741 return 0; /* assigned */
744 ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv, dbuf, size,
748 * bind with 'priv' now to avoid warning in failure path
749 * of requesting firmware.
751 firmware->priv = fw_priv;
754 ret = fw_state_wait(fw_priv);
756 fw_set_page_data(fw_priv, firmware);
757 return 0; /* assigned */
763 return 1; /* need to load */
767 * Batched requests need only one wake, we need to do this step last due to the
768 * fallback mechanism. The buf is protected with kref_get(), and it won't be
769 * released until the last user calls release_firmware().
771 * Failed batched requests are possible as well, in such cases we just share
772 * the struct fw_priv and won't release it until all requests are woken
773 * and have gone through this same path.
775 static void fw_abort_batch_reqs(struct firmware *fw)
777 struct fw_priv *fw_priv;
779 /* Loaded directly? */
780 if (!fw || !fw->priv)
784 if (!fw_state_is_aborted(fw_priv))
785 fw_state_aborted(fw_priv);
788 /* called from request_firmware() and request_firmware_work_func() */
790 _request_firmware(const struct firmware **firmware_p, const char *name,
791 struct device *device, void *buf, size_t size,
792 size_t offset, u32 opt_flags)
794 struct firmware *fw = NULL;
795 bool nondirect = false;
801 if (!name || name[0] == '\0') {
806 ret = _request_firmware_prepare(&fw, name, device, buf, size,
808 if (ret <= 0) /* error or already assigned */
811 ret = fw_get_filesystem_firmware(device, fw->priv, "", NULL);
813 /* Only full reads can support decompression, platform, and sysfs. */
814 if (!(opt_flags & FW_OPT_PARTIAL))
817 #ifdef CONFIG_FW_LOADER_COMPRESS
818 if (ret == -ENOENT && nondirect)
819 ret = fw_get_filesystem_firmware(device, fw->priv, ".xz",
822 if (ret == -ENOENT && nondirect)
823 ret = firmware_fallback_platform(fw->priv);
826 if (!(opt_flags & FW_OPT_NO_WARN))
828 "Direct firmware load for %s failed with error %d\n",
831 ret = firmware_fallback_sysfs(fw, name, device,
834 ret = assign_fw(fw, device);
838 fw_abort_batch_reqs(fw);
839 release_firmware(fw);
848 * request_firmware() - send firmware request and wait for it
849 * @firmware_p: pointer to firmware image
850 * @name: name of firmware file
851 * @device: device for which firmware is being loaded
853 * @firmware_p will be used to return a firmware image by the name
854 * of @name for device @device.
856 * Should be called from user context where sleeping is allowed.
858 * @name will be used as $FIRMWARE in the uevent environment and
859 * should be distinctive enough not to be confused with any other
860 * firmware image for this or any other device.
862 * Caller must hold the reference count of @device.
864 * The function can be called safely inside device's suspend and
868 request_firmware(const struct firmware **firmware_p, const char *name,
869 struct device *device)
873 /* Need to pin this module until return */
874 __module_get(THIS_MODULE);
875 ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
877 module_put(THIS_MODULE);
880 EXPORT_SYMBOL(request_firmware);
883 * firmware_request_nowarn() - request for an optional fw module
884 * @firmware: pointer to firmware image
885 * @name: name of firmware file
886 * @device: device for which firmware is being loaded
888 * This function is similar in behaviour to request_firmware(), except it
889 * doesn't produce warning messages when the file is not found. The sysfs
890 * fallback mechanism is enabled if direct filesystem lookup fails. However,
891 * failures to find the firmware file with it are still suppressed. It is
892 * therefore up to the driver to check for the return value of this call and to
893 * decide when to inform the users of errors.
895 int firmware_request_nowarn(const struct firmware **firmware, const char *name,
896 struct device *device)
900 /* Need to pin this module until return */
901 __module_get(THIS_MODULE);
902 ret = _request_firmware(firmware, name, device, NULL, 0, 0,
903 FW_OPT_UEVENT | FW_OPT_NO_WARN);
904 module_put(THIS_MODULE);
907 EXPORT_SYMBOL_GPL(firmware_request_nowarn);
910 * request_firmware_direct() - load firmware directly without usermode helper
911 * @firmware_p: pointer to firmware image
912 * @name: name of firmware file
913 * @device: device for which firmware is being loaded
915 * This function works pretty much like request_firmware(), but this doesn't
916 * fall back to usermode helper even if the firmware couldn't be loaded
917 * directly from fs. Hence it's useful for loading optional firmwares, which
918 * aren't always present, without extra long timeouts of udev.
920 int request_firmware_direct(const struct firmware **firmware_p,
921 const char *name, struct device *device)
925 __module_get(THIS_MODULE);
926 ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
927 FW_OPT_UEVENT | FW_OPT_NO_WARN |
928 FW_OPT_NOFALLBACK_SYSFS);
929 module_put(THIS_MODULE);
932 EXPORT_SYMBOL_GPL(request_firmware_direct);
935 * firmware_request_platform() - request firmware with platform-fw fallback
936 * @firmware: pointer to firmware image
937 * @name: name of firmware file
938 * @device: device for which firmware is being loaded
940 * This function is similar in behaviour to request_firmware, except that if
941 * direct filesystem lookup fails, it will fallback to looking for a copy of the
942 * requested firmware embedded in the platform's main (e.g. UEFI) firmware.
944 int firmware_request_platform(const struct firmware **firmware,
945 const char *name, struct device *device)
949 /* Need to pin this module until return */
950 __module_get(THIS_MODULE);
951 ret = _request_firmware(firmware, name, device, NULL, 0, 0,
952 FW_OPT_UEVENT | FW_OPT_FALLBACK_PLATFORM);
953 module_put(THIS_MODULE);
956 EXPORT_SYMBOL_GPL(firmware_request_platform);
959 * firmware_request_cache() - cache firmware for suspend so resume can use it
960 * @name: name of firmware file
961 * @device: device for which firmware should be cached for
963 * There are some devices with an optimization that enables the device to not
964 * require loading firmware on system reboot. This optimization may still
965 * require the firmware present on resume from suspend. This routine can be
966 * used to ensure the firmware is present on resume from suspend in these
967 * situations. This helper is not compatible with drivers which use
968 * request_firmware_into_buf() or request_firmware_nowait() with no uevent set.
970 int firmware_request_cache(struct device *device, const char *name)
974 mutex_lock(&fw_lock);
975 ret = fw_add_devm_name(device, name);
976 mutex_unlock(&fw_lock);
980 EXPORT_SYMBOL_GPL(firmware_request_cache);
983 * request_firmware_into_buf() - load firmware into a previously allocated buffer
984 * @firmware_p: pointer to firmware image
985 * @name: name of firmware file
986 * @device: device for which firmware is being loaded and DMA region allocated
987 * @buf: address of buffer to load firmware into
988 * @size: size of buffer
990 * This function works pretty much like request_firmware(), but it doesn't
991 * allocate a buffer to hold the firmware data. Instead, the firmware
992 * is loaded directly into the buffer pointed to by @buf and the @firmware_p
993 * data member is pointed at @buf.
995 * This function doesn't cache firmware either.
998 request_firmware_into_buf(const struct firmware **firmware_p, const char *name,
999 struct device *device, void *buf, size_t size)
1003 if (fw_cache_is_setup(device, name))
1006 __module_get(THIS_MODULE);
1007 ret = _request_firmware(firmware_p, name, device, buf, size, 0,
1008 FW_OPT_UEVENT | FW_OPT_NOCACHE);
1009 module_put(THIS_MODULE);
1012 EXPORT_SYMBOL(request_firmware_into_buf);
1015 * request_partial_firmware_into_buf() - load partial firmware into a previously allocated buffer
1016 * @firmware_p: pointer to firmware image
1017 * @name: name of firmware file
1018 * @device: device for which firmware is being loaded and DMA region allocated
1019 * @buf: address of buffer to load firmware into
1020 * @size: size of buffer
1021 * @offset: offset into file to read
1023 * This function works pretty much like request_firmware_into_buf except
1024 * it allows a partial read of the file.
1027 request_partial_firmware_into_buf(const struct firmware **firmware_p,
1028 const char *name, struct device *device,
1029 void *buf, size_t size, size_t offset)
1033 if (fw_cache_is_setup(device, name))
1036 __module_get(THIS_MODULE);
1037 ret = _request_firmware(firmware_p, name, device, buf, size, offset,
1038 FW_OPT_UEVENT | FW_OPT_NOCACHE |
1040 module_put(THIS_MODULE);
1043 EXPORT_SYMBOL(request_partial_firmware_into_buf);
1046 * release_firmware() - release the resource associated with a firmware image
1047 * @fw: firmware resource to release
1049 void release_firmware(const struct firmware *fw)
1052 if (!fw_is_builtin_firmware(fw))
1053 firmware_free_data(fw);
1057 EXPORT_SYMBOL(release_firmware);
1060 struct firmware_work {
1061 struct work_struct work;
1062 struct module *module;
1064 struct device *device;
1066 void (*cont)(const struct firmware *fw, void *context);
1070 static void request_firmware_work_func(struct work_struct *work)
1072 struct firmware_work *fw_work;
1073 const struct firmware *fw;
1075 fw_work = container_of(work, struct firmware_work, work);
1077 _request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0, 0,
1078 fw_work->opt_flags);
1079 fw_work->cont(fw, fw_work->context);
1080 put_device(fw_work->device); /* taken in request_firmware_nowait() */
1082 module_put(fw_work->module);
1083 kfree_const(fw_work->name);
1088 * request_firmware_nowait() - asynchronous version of request_firmware
1089 * @module: module requesting the firmware
1090 * @uevent: sends uevent to copy the firmware image if this flag
1091 * is non-zero else the firmware copy must be done manually.
1092 * @name: name of firmware file
1093 * @device: device for which firmware is being loaded
1094 * @gfp: allocation flags
1095 * @context: will be passed over to @cont, and
1096 * @fw may be %NULL if firmware request fails.
1097 * @cont: function will be called asynchronously when the firmware
1100 * Caller must hold the reference count of @device.
1102 * Asynchronous variant of request_firmware() for user contexts:
1103 * - sleep for as small periods as possible since it may
1104 * increase kernel boot time of built-in device drivers
1105 * requesting firmware in their ->probe() methods, if
1106 * @gfp is GFP_KERNEL.
1108 * - can't sleep at all if @gfp is GFP_ATOMIC.
1111 request_firmware_nowait(
1112 struct module *module, bool uevent,
1113 const char *name, struct device *device, gfp_t gfp, void *context,
1114 void (*cont)(const struct firmware *fw, void *context))
1116 struct firmware_work *fw_work;
1118 fw_work = kzalloc(sizeof(struct firmware_work), gfp);
1122 fw_work->module = module;
1123 fw_work->name = kstrdup_const(name, gfp);
1124 if (!fw_work->name) {
1128 fw_work->device = device;
1129 fw_work->context = context;
1130 fw_work->cont = cont;
1131 fw_work->opt_flags = FW_OPT_NOWAIT |
1132 (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
1134 if (!uevent && fw_cache_is_setup(device, name)) {
1135 kfree_const(fw_work->name);
1140 if (!try_module_get(module)) {
1141 kfree_const(fw_work->name);
1146 get_device(fw_work->device);
1147 INIT_WORK(&fw_work->work, request_firmware_work_func);
1148 schedule_work(&fw_work->work);
1151 EXPORT_SYMBOL(request_firmware_nowait);
1153 #ifdef CONFIG_FW_CACHE
1154 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1157 * cache_firmware() - cache one firmware image in kernel memory space
1158 * @fw_name: the firmware image name
1160 * Cache firmware in kernel memory so that drivers can use it when
1161 * system isn't ready for them to request firmware image from userspace.
1162 * Once it returns successfully, driver can use request_firmware or its
1163 * nowait version to get the cached firmware without any interacting
1166 * Return 0 if the firmware image has been cached successfully
1167 * Return !0 otherwise
1170 static int cache_firmware(const char *fw_name)
1173 const struct firmware *fw;
1175 pr_debug("%s: %s\n", __func__, fw_name);
1177 ret = request_firmware(&fw, fw_name, NULL);
1181 pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1186 static struct fw_priv *lookup_fw_priv(const char *fw_name)
1188 struct fw_priv *tmp;
1189 struct firmware_cache *fwc = &fw_cache;
1191 spin_lock(&fwc->lock);
1192 tmp = __lookup_fw_priv(fw_name);
1193 spin_unlock(&fwc->lock);
1199 * uncache_firmware() - remove one cached firmware image
1200 * @fw_name: the firmware image name
1202 * Uncache one firmware image which has been cached successfully
1205 * Return 0 if the firmware cache has been removed successfully
1206 * Return !0 otherwise
1209 static int uncache_firmware(const char *fw_name)
1211 struct fw_priv *fw_priv;
1214 pr_debug("%s: %s\n", __func__, fw_name);
1216 if (fw_get_builtin_firmware(&fw, fw_name, NULL, 0))
1219 fw_priv = lookup_fw_priv(fw_name);
1221 free_fw_priv(fw_priv);
1228 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1230 struct fw_cache_entry *fce;
1232 fce = kzalloc(sizeof(*fce), GFP_ATOMIC);
1236 fce->name = kstrdup_const(name, GFP_ATOMIC);
1246 static int __fw_entry_found(const char *name)
1248 struct firmware_cache *fwc = &fw_cache;
1249 struct fw_cache_entry *fce;
1251 list_for_each_entry(fce, &fwc->fw_names, list) {
1252 if (!strcmp(fce->name, name))
1258 static int fw_cache_piggyback_on_request(const char *name)
1260 struct firmware_cache *fwc = &fw_cache;
1261 struct fw_cache_entry *fce;
1264 spin_lock(&fwc->name_lock);
1265 if (__fw_entry_found(name))
1268 fce = alloc_fw_cache_entry(name);
1271 list_add(&fce->list, &fwc->fw_names);
1272 pr_debug("%s: fw: %s\n", __func__, name);
1275 spin_unlock(&fwc->name_lock);
1279 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1281 kfree_const(fce->name);
1285 static void __async_dev_cache_fw_image(void *fw_entry,
1286 async_cookie_t cookie)
1288 struct fw_cache_entry *fce = fw_entry;
1289 struct firmware_cache *fwc = &fw_cache;
1292 ret = cache_firmware(fce->name);
1294 spin_lock(&fwc->name_lock);
1295 list_del(&fce->list);
1296 spin_unlock(&fwc->name_lock);
1298 free_fw_cache_entry(fce);
1302 /* called with dev->devres_lock held */
1303 static void dev_create_fw_entry(struct device *dev, void *res,
1306 struct fw_name_devm *fwn = res;
1307 const char *fw_name = fwn->name;
1308 struct list_head *head = data;
1309 struct fw_cache_entry *fce;
1311 fce = alloc_fw_cache_entry(fw_name);
1313 list_add(&fce->list, head);
1316 static int devm_name_match(struct device *dev, void *res,
1319 struct fw_name_devm *fwn = res;
1320 return (fwn->magic == (unsigned long)match_data);
1323 static void dev_cache_fw_image(struct device *dev, void *data)
1326 struct fw_cache_entry *fce;
1327 struct fw_cache_entry *fce_next;
1328 struct firmware_cache *fwc = &fw_cache;
1330 devres_for_each_res(dev, fw_name_devm_release,
1331 devm_name_match, &fw_cache,
1332 dev_create_fw_entry, &todo);
1334 list_for_each_entry_safe(fce, fce_next, &todo, list) {
1335 list_del(&fce->list);
1337 spin_lock(&fwc->name_lock);
1338 /* only one cache entry for one firmware */
1339 if (!__fw_entry_found(fce->name)) {
1340 list_add(&fce->list, &fwc->fw_names);
1342 free_fw_cache_entry(fce);
1345 spin_unlock(&fwc->name_lock);
1348 async_schedule_domain(__async_dev_cache_fw_image,
1354 static void __device_uncache_fw_images(void)
1356 struct firmware_cache *fwc = &fw_cache;
1357 struct fw_cache_entry *fce;
1359 spin_lock(&fwc->name_lock);
1360 while (!list_empty(&fwc->fw_names)) {
1361 fce = list_entry(fwc->fw_names.next,
1362 struct fw_cache_entry, list);
1363 list_del(&fce->list);
1364 spin_unlock(&fwc->name_lock);
1366 uncache_firmware(fce->name);
1367 free_fw_cache_entry(fce);
1369 spin_lock(&fwc->name_lock);
1371 spin_unlock(&fwc->name_lock);
1375 * device_cache_fw_images() - cache devices' firmware
1377 * If one device called request_firmware or its nowait version
1378 * successfully before, the firmware names are recored into the
1379 * device's devres link list, so device_cache_fw_images can call
1380 * cache_firmware() to cache these firmwares for the device,
1381 * then the device driver can load its firmwares easily at
1382 * time when system is not ready to complete loading firmware.
1384 static void device_cache_fw_images(void)
1386 struct firmware_cache *fwc = &fw_cache;
1389 pr_debug("%s\n", __func__);
1391 /* cancel uncache work */
1392 cancel_delayed_work_sync(&fwc->work);
1394 fw_fallback_set_cache_timeout();
1396 mutex_lock(&fw_lock);
1397 fwc->state = FW_LOADER_START_CACHE;
1398 dpm_for_each_dev(NULL, dev_cache_fw_image);
1399 mutex_unlock(&fw_lock);
1401 /* wait for completion of caching firmware for all devices */
1402 async_synchronize_full_domain(&fw_cache_domain);
1404 fw_fallback_set_default_timeout();
1408 * device_uncache_fw_images() - uncache devices' firmware
1410 * uncache all firmwares which have been cached successfully
1411 * by device_uncache_fw_images earlier
1413 static void device_uncache_fw_images(void)
1415 pr_debug("%s\n", __func__);
1416 __device_uncache_fw_images();
1419 static void device_uncache_fw_images_work(struct work_struct *work)
1421 device_uncache_fw_images();
1425 * device_uncache_fw_images_delay() - uncache devices firmwares
1426 * @delay: number of milliseconds to delay uncache device firmwares
1428 * uncache all devices's firmwares which has been cached successfully
1429 * by device_cache_fw_images after @delay milliseconds.
1431 static void device_uncache_fw_images_delay(unsigned long delay)
1433 queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1434 msecs_to_jiffies(delay));
1437 static int fw_pm_notify(struct notifier_block *notify_block,
1438 unsigned long mode, void *unused)
1441 case PM_HIBERNATION_PREPARE:
1442 case PM_SUSPEND_PREPARE:
1443 case PM_RESTORE_PREPARE:
1445 * kill pending fallback requests with a custom fallback
1446 * to avoid stalling suspend.
1448 kill_pending_fw_fallback_reqs(true);
1449 device_cache_fw_images();
1452 case PM_POST_SUSPEND:
1453 case PM_POST_HIBERNATION:
1454 case PM_POST_RESTORE:
1456 * In case that system sleep failed and syscore_suspend is
1459 mutex_lock(&fw_lock);
1460 fw_cache.state = FW_LOADER_NO_CACHE;
1461 mutex_unlock(&fw_lock);
1463 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1470 /* stop caching firmware once syscore_suspend is reached */
1471 static int fw_suspend(void)
1473 fw_cache.state = FW_LOADER_NO_CACHE;
1477 static struct syscore_ops fw_syscore_ops = {
1478 .suspend = fw_suspend,
1481 static int __init register_fw_pm_ops(void)
1485 spin_lock_init(&fw_cache.name_lock);
1486 INIT_LIST_HEAD(&fw_cache.fw_names);
1488 INIT_DELAYED_WORK(&fw_cache.work,
1489 device_uncache_fw_images_work);
1491 fw_cache.pm_notify.notifier_call = fw_pm_notify;
1492 ret = register_pm_notifier(&fw_cache.pm_notify);
1496 register_syscore_ops(&fw_syscore_ops);
1501 static inline void unregister_fw_pm_ops(void)
1503 unregister_syscore_ops(&fw_syscore_ops);
1504 unregister_pm_notifier(&fw_cache.pm_notify);
1507 static int fw_cache_piggyback_on_request(const char *name)
1511 static inline int register_fw_pm_ops(void)
1515 static inline void unregister_fw_pm_ops(void)
1520 static void __init fw_cache_init(void)
1522 spin_lock_init(&fw_cache.lock);
1523 INIT_LIST_HEAD(&fw_cache.head);
1524 fw_cache.state = FW_LOADER_NO_CACHE;
1527 static int fw_shutdown_notify(struct notifier_block *unused1,
1528 unsigned long unused2, void *unused3)
1531 * Kill all pending fallback requests to avoid both stalling shutdown,
1532 * and avoid a deadlock with the usermode_lock.
1534 kill_pending_fw_fallback_reqs(false);
1539 static struct notifier_block fw_shutdown_nb = {
1540 .notifier_call = fw_shutdown_notify,
1543 static int __init firmware_class_init(void)
1547 /* No need to unfold these on exit */
1550 ret = register_fw_pm_ops();
1554 ret = register_reboot_notifier(&fw_shutdown_nb);
1558 return register_sysfs_loader();
1561 unregister_fw_pm_ops();
1565 static void __exit firmware_class_exit(void)
1567 unregister_fw_pm_ops();
1568 unregister_reboot_notifier(&fw_shutdown_nb);
1569 unregister_sysfs_loader();
1572 fs_initcall(firmware_class_init);
1573 module_exit(firmware_class_exit);