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/module.h>
16 #include <linux/init.h>
17 #include <linux/timer.h>
18 #include <linux/vmalloc.h>
19 #include <linux/interrupt.h>
20 #include <linux/bitops.h>
21 #include <linux/mutex.h>
22 #include <linux/workqueue.h>
23 #include <linux/highmem.h>
24 #include <linux/firmware.h>
25 #include <linux/slab.h>
26 #include <linux/sched.h>
27 #include <linux/file.h>
28 #include <linux/list.h>
30 #include <linux/async.h>
32 #include <linux/suspend.h>
33 #include <linux/syscore_ops.h>
34 #include <linux/reboot.h>
35 #include <linux/security.h>
38 #include <generated/utsrelease.h>
44 MODULE_AUTHOR("Manuel Estrada Sainz");
45 MODULE_DESCRIPTION("Multi purpose firmware loading support");
46 MODULE_LICENSE("GPL");
48 struct firmware_cache {
49 /* firmware_buf instance will be added into the below list */
51 struct list_head head;
54 #ifdef CONFIG_FW_CACHE
56 * Names of firmware images which have been cached successfully
57 * will be added into the below list so that device uncache
58 * helper can trace which firmware images have been cached
62 struct list_head fw_names;
64 struct delayed_work work;
66 struct notifier_block pm_notify;
70 struct fw_cache_entry {
71 struct list_head list;
80 static inline struct fw_priv *to_fw_priv(struct kref *ref)
82 return container_of(ref, struct fw_priv, ref);
85 #define FW_LOADER_NO_CACHE 0
86 #define FW_LOADER_START_CACHE 1
88 /* fw_lock could be moved to 'struct fw_sysfs' but since it is just
89 * guarding for corner cases a global lock should be OK */
90 DEFINE_MUTEX(fw_lock);
92 static struct firmware_cache fw_cache;
94 /* Builtin firmware support */
96 #ifdef CONFIG_FW_LOADER
98 extern struct builtin_fw __start_builtin_fw[];
99 extern struct builtin_fw __end_builtin_fw[];
101 static void fw_copy_to_prealloc_buf(struct firmware *fw,
102 void *buf, size_t size)
104 if (!buf || size < fw->size)
106 memcpy(buf, fw->data, fw->size);
109 static bool fw_get_builtin_firmware(struct firmware *fw, const char *name,
110 void *buf, size_t size)
112 struct builtin_fw *b_fw;
114 for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
115 if (strcmp(name, b_fw->name) == 0) {
116 fw->size = b_fw->size;
117 fw->data = b_fw->data;
118 fw_copy_to_prealloc_buf(fw, buf, size);
127 static bool fw_is_builtin_firmware(const struct firmware *fw)
129 struct builtin_fw *b_fw;
131 for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
132 if (fw->data == b_fw->data)
138 #else /* Module case - no builtin firmware support */
140 static inline bool fw_get_builtin_firmware(struct firmware *fw,
141 const char *name, void *buf,
147 static inline bool fw_is_builtin_firmware(const struct firmware *fw)
153 static void fw_state_init(struct fw_priv *fw_priv)
155 struct fw_state *fw_st = &fw_priv->fw_st;
157 init_completion(&fw_st->completion);
158 fw_st->status = FW_STATUS_UNKNOWN;
161 static inline int fw_state_wait(struct fw_priv *fw_priv)
163 return __fw_state_wait_common(fw_priv, MAX_SCHEDULE_TIMEOUT);
166 static int fw_cache_piggyback_on_request(const char *name);
168 static struct fw_priv *__allocate_fw_priv(const char *fw_name,
169 struct firmware_cache *fwc,
170 void *dbuf, size_t size)
172 struct fw_priv *fw_priv;
174 fw_priv = kzalloc(sizeof(*fw_priv), GFP_ATOMIC);
178 fw_priv->fw_name = kstrdup_const(fw_name, GFP_ATOMIC);
179 if (!fw_priv->fw_name) {
184 kref_init(&fw_priv->ref);
186 fw_priv->data = dbuf;
187 fw_priv->allocated_size = size;
188 fw_state_init(fw_priv);
189 #ifdef CONFIG_FW_LOADER_USER_HELPER
190 INIT_LIST_HEAD(&fw_priv->pending_list);
193 pr_debug("%s: fw-%s fw_priv=%p\n", __func__, fw_name, fw_priv);
198 static struct fw_priv *__lookup_fw_priv(const char *fw_name)
201 struct firmware_cache *fwc = &fw_cache;
203 list_for_each_entry(tmp, &fwc->head, list)
204 if (!strcmp(tmp->fw_name, fw_name))
209 /* Returns 1 for batching firmware requests with the same name */
210 static int alloc_lookup_fw_priv(const char *fw_name,
211 struct firmware_cache *fwc,
212 struct fw_priv **fw_priv, void *dbuf,
213 size_t size, enum fw_opt opt_flags)
217 spin_lock(&fwc->lock);
218 if (!(opt_flags & FW_OPT_NOCACHE)) {
219 tmp = __lookup_fw_priv(fw_name);
222 spin_unlock(&fwc->lock);
224 pr_debug("batched request - sharing the same struct fw_priv and lookup for multiple requests\n");
229 tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size);
231 INIT_LIST_HEAD(&tmp->list);
232 if (!(opt_flags & FW_OPT_NOCACHE))
233 list_add(&tmp->list, &fwc->head);
235 spin_unlock(&fwc->lock);
239 return tmp ? 0 : -ENOMEM;
242 static void __free_fw_priv(struct kref *ref)
243 __releases(&fwc->lock)
245 struct fw_priv *fw_priv = to_fw_priv(ref);
246 struct firmware_cache *fwc = fw_priv->fwc;
248 pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
249 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
250 (unsigned int)fw_priv->size);
252 list_del(&fw_priv->list);
253 spin_unlock(&fwc->lock);
255 fw_free_paged_buf(fw_priv); /* free leftover pages */
256 if (!fw_priv->allocated_size)
257 vfree(fw_priv->data);
258 kfree_const(fw_priv->fw_name);
262 static void free_fw_priv(struct fw_priv *fw_priv)
264 struct firmware_cache *fwc = fw_priv->fwc;
265 spin_lock(&fwc->lock);
266 if (!kref_put(&fw_priv->ref, __free_fw_priv))
267 spin_unlock(&fwc->lock);
270 #ifdef CONFIG_FW_LOADER_PAGED_BUF
271 void fw_free_paged_buf(struct fw_priv *fw_priv)
278 for (i = 0; i < fw_priv->nr_pages; i++)
279 __free_page(fw_priv->pages[i]);
280 kvfree(fw_priv->pages);
281 fw_priv->pages = NULL;
282 fw_priv->page_array_size = 0;
283 fw_priv->nr_pages = 0;
286 int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed)
288 /* If the array of pages is too small, grow it */
289 if (fw_priv->page_array_size < pages_needed) {
290 int new_array_size = max(pages_needed,
291 fw_priv->page_array_size * 2);
292 struct page **new_pages;
294 new_pages = kvmalloc_array(new_array_size, sizeof(void *),
298 memcpy(new_pages, fw_priv->pages,
299 fw_priv->page_array_size * sizeof(void *));
300 memset(&new_pages[fw_priv->page_array_size], 0, sizeof(void *) *
301 (new_array_size - fw_priv->page_array_size));
302 kvfree(fw_priv->pages);
303 fw_priv->pages = new_pages;
304 fw_priv->page_array_size = new_array_size;
307 while (fw_priv->nr_pages < pages_needed) {
308 fw_priv->pages[fw_priv->nr_pages] =
309 alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
311 if (!fw_priv->pages[fw_priv->nr_pages])
319 int fw_map_paged_buf(struct fw_priv *fw_priv)
321 /* one pages buffer should be mapped/unmapped only once */
325 vunmap(fw_priv->data);
326 fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages, 0,
331 /* page table is no longer needed after mapping, let's free */
332 kvfree(fw_priv->pages);
333 fw_priv->pages = NULL;
340 * XZ-compressed firmware support
342 #ifdef CONFIG_FW_LOADER_COMPRESS
343 /* show an error and return the standard error code */
344 static int fw_decompress_xz_error(struct device *dev, enum xz_ret xz_ret)
346 if (xz_ret != XZ_STREAM_END) {
347 dev_warn(dev, "xz decompression failed (xz_ret=%d)\n", xz_ret);
348 return xz_ret == XZ_MEM_ERROR ? -ENOMEM : -EINVAL;
353 /* single-shot decompression onto the pre-allocated buffer */
354 static int fw_decompress_xz_single(struct device *dev, struct fw_priv *fw_priv,
355 size_t in_size, const void *in_buffer)
357 struct xz_dec *xz_dec;
358 struct xz_buf xz_buf;
361 xz_dec = xz_dec_init(XZ_SINGLE, (u32)-1);
365 xz_buf.in_size = in_size;
366 xz_buf.in = in_buffer;
368 xz_buf.out_size = fw_priv->allocated_size;
369 xz_buf.out = fw_priv->data;
372 xz_ret = xz_dec_run(xz_dec, &xz_buf);
375 fw_priv->size = xz_buf.out_pos;
376 return fw_decompress_xz_error(dev, xz_ret);
379 /* decompression on paged buffer and map it */
380 static int fw_decompress_xz_pages(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;
389 xz_dec = xz_dec_init(XZ_DYNALLOC, (u32)-1);
393 xz_buf.in_size = in_size;
394 xz_buf.in = in_buffer;
397 fw_priv->is_paged_buf = true;
400 if (fw_grow_paged_buf(fw_priv, fw_priv->nr_pages + 1)) {
405 /* decompress onto the new allocated page */
406 page = fw_priv->pages[fw_priv->nr_pages - 1];
407 xz_buf.out = kmap(page);
409 xz_buf.out_size = PAGE_SIZE;
410 xz_ret = xz_dec_run(xz_dec, &xz_buf);
412 fw_priv->size += xz_buf.out_pos;
413 /* partial decompression means either end or error */
414 if (xz_buf.out_pos != PAGE_SIZE)
416 } while (xz_ret == XZ_OK);
418 err = fw_decompress_xz_error(dev, xz_ret);
420 err = fw_map_paged_buf(fw_priv);
427 static int fw_decompress_xz(struct device *dev, struct fw_priv *fw_priv,
428 size_t in_size, const void *in_buffer)
430 /* if the buffer is pre-allocated, we can perform in single-shot mode */
432 return fw_decompress_xz_single(dev, fw_priv, in_size, in_buffer);
434 return fw_decompress_xz_pages(dev, fw_priv, in_size, in_buffer);
436 #endif /* CONFIG_FW_LOADER_COMPRESS */
438 /* direct firmware loading support */
439 static char fw_path_para[256];
440 static const char * const fw_path[] = {
442 "/lib/firmware/updates/" UTS_RELEASE,
443 "/lib/firmware/updates",
444 "/lib/firmware/" UTS_RELEASE,
449 * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
450 * from kernel command line because firmware_class is generally built in
451 * kernel instead of module.
453 module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
454 MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
457 fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv,
459 int (*decompress)(struct device *dev,
460 struct fw_priv *fw_priv,
462 const void *in_buffer))
468 enum kernel_read_file_id id = READING_FIRMWARE;
469 size_t msize = INT_MAX;
472 /* Already populated data member means we're loading into a buffer */
473 if (!decompress && fw_priv->data) {
474 buffer = fw_priv->data;
475 id = READING_FIRMWARE_PREALLOC_BUFFER;
476 msize = fw_priv->allocated_size;
483 for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
484 /* skip the unset customized path */
488 len = snprintf(path, PATH_MAX, "%s/%s%s",
489 fw_path[i], fw_priv->fw_name, suffix);
490 if (len >= PATH_MAX) {
497 /* load firmware files from the mount namespace of init */
498 rc = kernel_read_file_from_path_initns(path, &buffer,
502 dev_warn(device, "loading %s failed with error %d\n",
505 dev_dbg(device, "loading %s failed for no such file or directory.\n",
509 dev_dbg(device, "Loading firmware from %s\n", path);
511 dev_dbg(device, "f/w decompressing %s\n",
513 rc = decompress(device, fw_priv, size, buffer);
514 /* discard the superfluous original content */
518 fw_free_paged_buf(fw_priv);
522 dev_dbg(device, "direct-loading %s\n",
525 fw_priv->data = buffer;
526 fw_priv->size = size;
528 fw_state_done(fw_priv);
536 /* firmware holds the ownership of pages */
537 static void firmware_free_data(const struct firmware *fw)
539 /* Loaded directly? */
544 free_fw_priv(fw->priv);
547 /* store the pages buffer info firmware from buf */
548 static void fw_set_page_data(struct fw_priv *fw_priv, struct firmware *fw)
551 #ifdef CONFIG_FW_LOADER_USER_HELPER
552 fw->pages = fw_priv->pages;
554 fw->size = fw_priv->size;
555 fw->data = fw_priv->data;
557 pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
558 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
559 (unsigned int)fw_priv->size);
562 #ifdef CONFIG_FW_CACHE
563 static void fw_name_devm_release(struct device *dev, void *res)
565 struct fw_name_devm *fwn = res;
567 if (fwn->magic == (unsigned long)&fw_cache)
568 pr_debug("%s: fw_name-%s devm-%p released\n",
569 __func__, fwn->name, res);
570 kfree_const(fwn->name);
573 static int fw_devm_match(struct device *dev, void *res,
576 struct fw_name_devm *fwn = res;
578 return (fwn->magic == (unsigned long)&fw_cache) &&
579 !strcmp(fwn->name, match_data);
582 static struct fw_name_devm *fw_find_devm_name(struct device *dev,
585 struct fw_name_devm *fwn;
587 fwn = devres_find(dev, fw_name_devm_release,
588 fw_devm_match, (void *)name);
592 static bool fw_cache_is_setup(struct device *dev, const char *name)
594 struct fw_name_devm *fwn;
596 fwn = fw_find_devm_name(dev, name);
603 /* add firmware name into devres list */
604 static int fw_add_devm_name(struct device *dev, const char *name)
606 struct fw_name_devm *fwn;
608 if (fw_cache_is_setup(dev, name))
611 fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm),
615 fwn->name = kstrdup_const(name, GFP_KERNEL);
621 fwn->magic = (unsigned long)&fw_cache;
622 devres_add(dev, fwn);
627 static bool fw_cache_is_setup(struct device *dev, const char *name)
632 static int fw_add_devm_name(struct device *dev, const char *name)
638 int assign_fw(struct firmware *fw, struct device *device,
639 enum fw_opt opt_flags)
641 struct fw_priv *fw_priv = fw->priv;
644 mutex_lock(&fw_lock);
645 if (!fw_priv->size || fw_state_is_aborted(fw_priv)) {
646 mutex_unlock(&fw_lock);
651 * add firmware name into devres list so that we can auto cache
652 * and uncache firmware for device.
654 * device may has been deleted already, but the problem
655 * should be fixed in devres or driver core.
657 /* don't cache firmware handled without uevent */
658 if (device && (opt_flags & FW_OPT_UEVENT) &&
659 !(opt_flags & FW_OPT_NOCACHE)) {
660 ret = fw_add_devm_name(device, fw_priv->fw_name);
662 mutex_unlock(&fw_lock);
668 * After caching firmware image is started, let it piggyback
669 * on request firmware.
671 if (!(opt_flags & FW_OPT_NOCACHE) &&
672 fw_priv->fwc->state == FW_LOADER_START_CACHE) {
673 if (fw_cache_piggyback_on_request(fw_priv->fw_name))
674 kref_get(&fw_priv->ref);
677 /* pass the pages buffer to driver at the last minute */
678 fw_set_page_data(fw_priv, fw);
679 mutex_unlock(&fw_lock);
683 /* prepare firmware and firmware_buf structs;
684 * return 0 if a firmware is already assigned, 1 if need to load one,
685 * or a negative error code
688 _request_firmware_prepare(struct firmware **firmware_p, const char *name,
689 struct device *device, void *dbuf, size_t size,
690 enum fw_opt opt_flags)
692 struct firmware *firmware;
693 struct fw_priv *fw_priv;
696 *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
698 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
703 if (fw_get_builtin_firmware(firmware, name, dbuf, size)) {
704 dev_dbg(device, "using built-in %s\n", name);
705 return 0; /* assigned */
708 ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv, dbuf, size,
712 * bind with 'priv' now to avoid warning in failure path
713 * of requesting firmware.
715 firmware->priv = fw_priv;
718 ret = fw_state_wait(fw_priv);
720 fw_set_page_data(fw_priv, firmware);
721 return 0; /* assigned */
727 return 1; /* need to load */
731 * Batched requests need only one wake, we need to do this step last due to the
732 * fallback mechanism. The buf is protected with kref_get(), and it won't be
733 * released until the last user calls release_firmware().
735 * Failed batched requests are possible as well, in such cases we just share
736 * the struct fw_priv and won't release it until all requests are woken
737 * and have gone through this same path.
739 static void fw_abort_batch_reqs(struct firmware *fw)
741 struct fw_priv *fw_priv;
743 /* Loaded directly? */
744 if (!fw || !fw->priv)
748 if (!fw_state_is_aborted(fw_priv))
749 fw_state_aborted(fw_priv);
752 /* called from request_firmware() and request_firmware_work_func() */
754 _request_firmware(const struct firmware **firmware_p, const char *name,
755 struct device *device, void *buf, size_t size,
756 enum fw_opt opt_flags)
758 struct firmware *fw = NULL;
764 if (!name || name[0] == '\0') {
769 ret = _request_firmware_prepare(&fw, name, device, buf, size,
771 if (ret <= 0) /* error or already assigned */
774 ret = fw_get_filesystem_firmware(device, fw->priv, "", NULL);
775 #ifdef CONFIG_FW_LOADER_COMPRESS
777 ret = fw_get_filesystem_firmware(device, fw->priv, ".xz",
782 ret = firmware_fallback_platform(fw->priv, opt_flags);
785 if (!(opt_flags & FW_OPT_NO_WARN))
787 "Direct firmware load for %s failed with error %d\n",
789 ret = firmware_fallback_sysfs(fw, name, device, opt_flags, ret);
791 ret = assign_fw(fw, device, opt_flags);
795 fw_abort_batch_reqs(fw);
796 release_firmware(fw);
805 * request_firmware() - send firmware request and wait for it
806 * @firmware_p: pointer to firmware image
807 * @name: name of firmware file
808 * @device: device for which firmware is being loaded
810 * @firmware_p will be used to return a firmware image by the name
811 * of @name for device @device.
813 * Should be called from user context where sleeping is allowed.
815 * @name will be used as $FIRMWARE in the uevent environment and
816 * should be distinctive enough not to be confused with any other
817 * firmware image for this or any other device.
819 * Caller must hold the reference count of @device.
821 * The function can be called safely inside device's suspend and
825 request_firmware(const struct firmware **firmware_p, const char *name,
826 struct device *device)
830 /* Need to pin this module until return */
831 __module_get(THIS_MODULE);
832 ret = _request_firmware(firmware_p, name, device, NULL, 0,
834 module_put(THIS_MODULE);
837 EXPORT_SYMBOL(request_firmware);
840 * firmware_request_nowarn() - request for an optional fw module
841 * @firmware: pointer to firmware image
842 * @name: name of firmware file
843 * @device: device for which firmware is being loaded
845 * This function is similar in behaviour to request_firmware(), except
846 * it doesn't produce warning messages when the file is not found.
847 * The sysfs fallback mechanism is enabled if direct filesystem lookup fails,
848 * however, however failures to find the firmware file with it are still
849 * suppressed. It is therefore up to the driver to check for the return value
850 * of this call and to decide when to inform the users of errors.
852 int firmware_request_nowarn(const struct firmware **firmware, const char *name,
853 struct device *device)
857 /* Need to pin this module until return */
858 __module_get(THIS_MODULE);
859 ret = _request_firmware(firmware, name, device, NULL, 0,
860 FW_OPT_UEVENT | FW_OPT_NO_WARN);
861 module_put(THIS_MODULE);
864 EXPORT_SYMBOL_GPL(firmware_request_nowarn);
867 * request_firmware_direct() - load firmware directly without usermode helper
868 * @firmware_p: pointer to firmware image
869 * @name: name of firmware file
870 * @device: device for which firmware is being loaded
872 * This function works pretty much like request_firmware(), but this doesn't
873 * fall back to usermode helper even if the firmware couldn't be loaded
874 * directly from fs. Hence it's useful for loading optional firmwares, which
875 * aren't always present, without extra long timeouts of udev.
877 int request_firmware_direct(const struct firmware **firmware_p,
878 const char *name, struct device *device)
882 __module_get(THIS_MODULE);
883 ret = _request_firmware(firmware_p, name, device, NULL, 0,
884 FW_OPT_UEVENT | FW_OPT_NO_WARN |
885 FW_OPT_NOFALLBACK_SYSFS);
886 module_put(THIS_MODULE);
889 EXPORT_SYMBOL_GPL(request_firmware_direct);
892 * firmware_request_platform() - request firmware with platform-fw fallback
893 * @firmware: pointer to firmware image
894 * @name: name of firmware file
895 * @device: device for which firmware is being loaded
897 * This function is similar in behaviour to request_firmware, except that if
898 * direct filesystem lookup fails, it will fallback to looking for a copy of the
899 * requested firmware embedded in the platform's main (e.g. UEFI) firmware.
901 int firmware_request_platform(const struct firmware **firmware,
902 const char *name, struct device *device)
906 /* Need to pin this module until return */
907 __module_get(THIS_MODULE);
908 ret = _request_firmware(firmware, name, device, NULL, 0,
909 FW_OPT_UEVENT | FW_OPT_FALLBACK_PLATFORM);
910 module_put(THIS_MODULE);
913 EXPORT_SYMBOL_GPL(firmware_request_platform);
916 * firmware_request_cache() - cache firmware for suspend so resume can use it
917 * @name: name of firmware file
918 * @device: device for which firmware should be cached for
920 * There are some devices with an optimization that enables the device to not
921 * require loading firmware on system reboot. This optimization may still
922 * require the firmware present on resume from suspend. This routine can be
923 * used to ensure the firmware is present on resume from suspend in these
924 * situations. This helper is not compatible with drivers which use
925 * request_firmware_into_buf() or request_firmware_nowait() with no uevent set.
927 int firmware_request_cache(struct device *device, const char *name)
931 mutex_lock(&fw_lock);
932 ret = fw_add_devm_name(device, name);
933 mutex_unlock(&fw_lock);
937 EXPORT_SYMBOL_GPL(firmware_request_cache);
940 * request_firmware_into_buf() - load firmware into a previously allocated buffer
941 * @firmware_p: pointer to firmware image
942 * @name: name of firmware file
943 * @device: device for which firmware is being loaded and DMA region allocated
944 * @buf: address of buffer to load firmware into
945 * @size: size of buffer
947 * This function works pretty much like request_firmware(), but it doesn't
948 * allocate a buffer to hold the firmware data. Instead, the firmware
949 * is loaded directly into the buffer pointed to by @buf and the @firmware_p
950 * data member is pointed at @buf.
952 * This function doesn't cache firmware either.
955 request_firmware_into_buf(const struct firmware **firmware_p, const char *name,
956 struct device *device, void *buf, size_t size)
960 if (fw_cache_is_setup(device, name))
963 __module_get(THIS_MODULE);
964 ret = _request_firmware(firmware_p, name, device, buf, size,
965 FW_OPT_UEVENT | FW_OPT_NOCACHE);
966 module_put(THIS_MODULE);
969 EXPORT_SYMBOL(request_firmware_into_buf);
972 * release_firmware() - release the resource associated with a firmware image
973 * @fw: firmware resource to release
975 void release_firmware(const struct firmware *fw)
978 if (!fw_is_builtin_firmware(fw))
979 firmware_free_data(fw);
983 EXPORT_SYMBOL(release_firmware);
986 struct firmware_work {
987 struct work_struct work;
988 struct module *module;
990 struct device *device;
992 void (*cont)(const struct firmware *fw, void *context);
993 enum fw_opt opt_flags;
996 static void request_firmware_work_func(struct work_struct *work)
998 struct firmware_work *fw_work;
999 const struct firmware *fw;
1001 fw_work = container_of(work, struct firmware_work, work);
1003 _request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0,
1004 fw_work->opt_flags);
1005 fw_work->cont(fw, fw_work->context);
1006 put_device(fw_work->device); /* taken in request_firmware_nowait() */
1008 module_put(fw_work->module);
1009 kfree_const(fw_work->name);
1014 * request_firmware_nowait() - asynchronous version of request_firmware
1015 * @module: module requesting the firmware
1016 * @uevent: sends uevent to copy the firmware image if this flag
1017 * is non-zero else the firmware copy must be done manually.
1018 * @name: name of firmware file
1019 * @device: device for which firmware is being loaded
1020 * @gfp: allocation flags
1021 * @context: will be passed over to @cont, and
1022 * @fw may be %NULL if firmware request fails.
1023 * @cont: function will be called asynchronously when the firmware
1026 * Caller must hold the reference count of @device.
1028 * Asynchronous variant of request_firmware() for user contexts:
1029 * - sleep for as small periods as possible since it may
1030 * increase kernel boot time of built-in device drivers
1031 * requesting firmware in their ->probe() methods, if
1032 * @gfp is GFP_KERNEL.
1034 * - can't sleep at all if @gfp is GFP_ATOMIC.
1037 request_firmware_nowait(
1038 struct module *module, bool uevent,
1039 const char *name, struct device *device, gfp_t gfp, void *context,
1040 void (*cont)(const struct firmware *fw, void *context))
1042 struct firmware_work *fw_work;
1044 fw_work = kzalloc(sizeof(struct firmware_work), gfp);
1048 fw_work->module = module;
1049 fw_work->name = kstrdup_const(name, gfp);
1050 if (!fw_work->name) {
1054 fw_work->device = device;
1055 fw_work->context = context;
1056 fw_work->cont = cont;
1057 fw_work->opt_flags = FW_OPT_NOWAIT |
1058 (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
1060 if (!uevent && fw_cache_is_setup(device, name)) {
1061 kfree_const(fw_work->name);
1066 if (!try_module_get(module)) {
1067 kfree_const(fw_work->name);
1072 get_device(fw_work->device);
1073 INIT_WORK(&fw_work->work, request_firmware_work_func);
1074 schedule_work(&fw_work->work);
1077 EXPORT_SYMBOL(request_firmware_nowait);
1079 #ifdef CONFIG_FW_CACHE
1080 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1083 * cache_firmware() - cache one firmware image in kernel memory space
1084 * @fw_name: the firmware image name
1086 * Cache firmware in kernel memory so that drivers can use it when
1087 * system isn't ready for them to request firmware image from userspace.
1088 * Once it returns successfully, driver can use request_firmware or its
1089 * nowait version to get the cached firmware without any interacting
1092 * Return 0 if the firmware image has been cached successfully
1093 * Return !0 otherwise
1096 static int cache_firmware(const char *fw_name)
1099 const struct firmware *fw;
1101 pr_debug("%s: %s\n", __func__, fw_name);
1103 ret = request_firmware(&fw, fw_name, NULL);
1107 pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1112 static struct fw_priv *lookup_fw_priv(const char *fw_name)
1114 struct fw_priv *tmp;
1115 struct firmware_cache *fwc = &fw_cache;
1117 spin_lock(&fwc->lock);
1118 tmp = __lookup_fw_priv(fw_name);
1119 spin_unlock(&fwc->lock);
1125 * uncache_firmware() - remove one cached firmware image
1126 * @fw_name: the firmware image name
1128 * Uncache one firmware image which has been cached successfully
1131 * Return 0 if the firmware cache has been removed successfully
1132 * Return !0 otherwise
1135 static int uncache_firmware(const char *fw_name)
1137 struct fw_priv *fw_priv;
1140 pr_debug("%s: %s\n", __func__, fw_name);
1142 if (fw_get_builtin_firmware(&fw, fw_name, NULL, 0))
1145 fw_priv = lookup_fw_priv(fw_name);
1147 free_fw_priv(fw_priv);
1154 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1156 struct fw_cache_entry *fce;
1158 fce = kzalloc(sizeof(*fce), GFP_ATOMIC);
1162 fce->name = kstrdup_const(name, GFP_ATOMIC);
1172 static int __fw_entry_found(const char *name)
1174 struct firmware_cache *fwc = &fw_cache;
1175 struct fw_cache_entry *fce;
1177 list_for_each_entry(fce, &fwc->fw_names, list) {
1178 if (!strcmp(fce->name, name))
1184 static int fw_cache_piggyback_on_request(const char *name)
1186 struct firmware_cache *fwc = &fw_cache;
1187 struct fw_cache_entry *fce;
1190 spin_lock(&fwc->name_lock);
1191 if (__fw_entry_found(name))
1194 fce = alloc_fw_cache_entry(name);
1197 list_add(&fce->list, &fwc->fw_names);
1198 pr_debug("%s: fw: %s\n", __func__, name);
1201 spin_unlock(&fwc->name_lock);
1205 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1207 kfree_const(fce->name);
1211 static void __async_dev_cache_fw_image(void *fw_entry,
1212 async_cookie_t cookie)
1214 struct fw_cache_entry *fce = fw_entry;
1215 struct firmware_cache *fwc = &fw_cache;
1218 ret = cache_firmware(fce->name);
1220 spin_lock(&fwc->name_lock);
1221 list_del(&fce->list);
1222 spin_unlock(&fwc->name_lock);
1224 free_fw_cache_entry(fce);
1228 /* called with dev->devres_lock held */
1229 static void dev_create_fw_entry(struct device *dev, void *res,
1232 struct fw_name_devm *fwn = res;
1233 const char *fw_name = fwn->name;
1234 struct list_head *head = data;
1235 struct fw_cache_entry *fce;
1237 fce = alloc_fw_cache_entry(fw_name);
1239 list_add(&fce->list, head);
1242 static int devm_name_match(struct device *dev, void *res,
1245 struct fw_name_devm *fwn = res;
1246 return (fwn->magic == (unsigned long)match_data);
1249 static void dev_cache_fw_image(struct device *dev, void *data)
1252 struct fw_cache_entry *fce;
1253 struct fw_cache_entry *fce_next;
1254 struct firmware_cache *fwc = &fw_cache;
1256 devres_for_each_res(dev, fw_name_devm_release,
1257 devm_name_match, &fw_cache,
1258 dev_create_fw_entry, &todo);
1260 list_for_each_entry_safe(fce, fce_next, &todo, list) {
1261 list_del(&fce->list);
1263 spin_lock(&fwc->name_lock);
1264 /* only one cache entry for one firmware */
1265 if (!__fw_entry_found(fce->name)) {
1266 list_add(&fce->list, &fwc->fw_names);
1268 free_fw_cache_entry(fce);
1271 spin_unlock(&fwc->name_lock);
1274 async_schedule_domain(__async_dev_cache_fw_image,
1280 static void __device_uncache_fw_images(void)
1282 struct firmware_cache *fwc = &fw_cache;
1283 struct fw_cache_entry *fce;
1285 spin_lock(&fwc->name_lock);
1286 while (!list_empty(&fwc->fw_names)) {
1287 fce = list_entry(fwc->fw_names.next,
1288 struct fw_cache_entry, list);
1289 list_del(&fce->list);
1290 spin_unlock(&fwc->name_lock);
1292 uncache_firmware(fce->name);
1293 free_fw_cache_entry(fce);
1295 spin_lock(&fwc->name_lock);
1297 spin_unlock(&fwc->name_lock);
1301 * device_cache_fw_images() - cache devices' firmware
1303 * If one device called request_firmware or its nowait version
1304 * successfully before, the firmware names are recored into the
1305 * device's devres link list, so device_cache_fw_images can call
1306 * cache_firmware() to cache these firmwares for the device,
1307 * then the device driver can load its firmwares easily at
1308 * time when system is not ready to complete loading firmware.
1310 static void device_cache_fw_images(void)
1312 struct firmware_cache *fwc = &fw_cache;
1315 pr_debug("%s\n", __func__);
1317 /* cancel uncache work */
1318 cancel_delayed_work_sync(&fwc->work);
1320 fw_fallback_set_cache_timeout();
1322 mutex_lock(&fw_lock);
1323 fwc->state = FW_LOADER_START_CACHE;
1324 dpm_for_each_dev(NULL, dev_cache_fw_image);
1325 mutex_unlock(&fw_lock);
1327 /* wait for completion of caching firmware for all devices */
1328 async_synchronize_full_domain(&fw_cache_domain);
1330 fw_fallback_set_default_timeout();
1334 * device_uncache_fw_images() - uncache devices' firmware
1336 * uncache all firmwares which have been cached successfully
1337 * by device_uncache_fw_images earlier
1339 static void device_uncache_fw_images(void)
1341 pr_debug("%s\n", __func__);
1342 __device_uncache_fw_images();
1345 static void device_uncache_fw_images_work(struct work_struct *work)
1347 device_uncache_fw_images();
1351 * device_uncache_fw_images_delay() - uncache devices firmwares
1352 * @delay: number of milliseconds to delay uncache device firmwares
1354 * uncache all devices's firmwares which has been cached successfully
1355 * by device_cache_fw_images after @delay milliseconds.
1357 static void device_uncache_fw_images_delay(unsigned long delay)
1359 queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1360 msecs_to_jiffies(delay));
1363 static int fw_pm_notify(struct notifier_block *notify_block,
1364 unsigned long mode, void *unused)
1367 case PM_HIBERNATION_PREPARE:
1368 case PM_SUSPEND_PREPARE:
1369 case PM_RESTORE_PREPARE:
1371 * kill pending fallback requests with a custom fallback
1372 * to avoid stalling suspend.
1374 kill_pending_fw_fallback_reqs(true);
1375 device_cache_fw_images();
1378 case PM_POST_SUSPEND:
1379 case PM_POST_HIBERNATION:
1380 case PM_POST_RESTORE:
1382 * In case that system sleep failed and syscore_suspend is
1385 mutex_lock(&fw_lock);
1386 fw_cache.state = FW_LOADER_NO_CACHE;
1387 mutex_unlock(&fw_lock);
1389 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1396 /* stop caching firmware once syscore_suspend is reached */
1397 static int fw_suspend(void)
1399 fw_cache.state = FW_LOADER_NO_CACHE;
1403 static struct syscore_ops fw_syscore_ops = {
1404 .suspend = fw_suspend,
1407 static int __init register_fw_pm_ops(void)
1411 spin_lock_init(&fw_cache.name_lock);
1412 INIT_LIST_HEAD(&fw_cache.fw_names);
1414 INIT_DELAYED_WORK(&fw_cache.work,
1415 device_uncache_fw_images_work);
1417 fw_cache.pm_notify.notifier_call = fw_pm_notify;
1418 ret = register_pm_notifier(&fw_cache.pm_notify);
1422 register_syscore_ops(&fw_syscore_ops);
1427 static inline void unregister_fw_pm_ops(void)
1429 unregister_syscore_ops(&fw_syscore_ops);
1430 unregister_pm_notifier(&fw_cache.pm_notify);
1433 static int fw_cache_piggyback_on_request(const char *name)
1437 static inline int register_fw_pm_ops(void)
1441 static inline void unregister_fw_pm_ops(void)
1446 static void __init fw_cache_init(void)
1448 spin_lock_init(&fw_cache.lock);
1449 INIT_LIST_HEAD(&fw_cache.head);
1450 fw_cache.state = FW_LOADER_NO_CACHE;
1453 static int fw_shutdown_notify(struct notifier_block *unused1,
1454 unsigned long unused2, void *unused3)
1457 * Kill all pending fallback requests to avoid both stalling shutdown,
1458 * and avoid a deadlock with the usermode_lock.
1460 kill_pending_fw_fallback_reqs(false);
1465 static struct notifier_block fw_shutdown_nb = {
1466 .notifier_call = fw_shutdown_notify,
1469 static int __init firmware_class_init(void)
1473 /* No need to unfold these on exit */
1476 ret = register_fw_pm_ops();
1480 ret = register_reboot_notifier(&fw_shutdown_nb);
1484 return register_sysfs_loader();
1487 unregister_fw_pm_ops();
1491 static void __exit firmware_class_exit(void)
1493 unregister_fw_pm_ops();
1494 unregister_reboot_notifier(&fw_shutdown_nb);
1495 unregister_sysfs_loader();
1498 fs_initcall(firmware_class_init);
1499 module_exit(firmware_class_exit);