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>
40 #include <generated/utsrelease.h>
46 MODULE_AUTHOR("Manuel Estrada Sainz");
47 MODULE_DESCRIPTION("Multi purpose firmware loading support");
48 MODULE_LICENSE("GPL");
50 struct firmware_cache {
51 /* firmware_buf instance will be added into the below list */
53 struct list_head head;
56 #ifdef CONFIG_FW_CACHE
58 * Names of firmware images which have been cached successfully
59 * will be added into the below list so that device uncache
60 * helper can trace which firmware images have been cached
64 struct list_head fw_names;
66 struct delayed_work work;
68 struct notifier_block pm_notify;
72 struct fw_cache_entry {
73 struct list_head list;
82 static inline struct fw_priv *to_fw_priv(struct kref *ref)
84 return container_of(ref, struct fw_priv, ref);
87 #define FW_LOADER_NO_CACHE 0
88 #define FW_LOADER_START_CACHE 1
90 /* fw_lock could be moved to 'struct fw_sysfs' but since it is just
91 * guarding for corner cases a global lock should be OK */
92 DEFINE_MUTEX(fw_lock);
94 static struct firmware_cache fw_cache;
96 /* Builtin firmware support */
98 #ifdef CONFIG_FW_LOADER
100 extern struct builtin_fw __start_builtin_fw[];
101 extern struct builtin_fw __end_builtin_fw[];
103 static void fw_copy_to_prealloc_buf(struct firmware *fw,
104 void *buf, size_t size)
106 if (!buf || size < fw->size)
108 memcpy(buf, fw->data, fw->size);
111 static bool fw_get_builtin_firmware(struct firmware *fw, const char *name,
112 void *buf, size_t size)
114 struct builtin_fw *b_fw;
116 for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
117 if (strcmp(name, b_fw->name) == 0) {
118 fw->size = b_fw->size;
119 fw->data = b_fw->data;
120 fw_copy_to_prealloc_buf(fw, buf, size);
129 static bool fw_is_builtin_firmware(const struct firmware *fw)
131 struct builtin_fw *b_fw;
133 for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
134 if (fw->data == b_fw->data)
140 #else /* Module case - no builtin firmware support */
142 static inline bool fw_get_builtin_firmware(struct firmware *fw,
143 const char *name, void *buf,
149 static inline bool fw_is_builtin_firmware(const struct firmware *fw)
155 static void fw_state_init(struct fw_priv *fw_priv)
157 struct fw_state *fw_st = &fw_priv->fw_st;
159 init_completion(&fw_st->completion);
160 fw_st->status = FW_STATUS_UNKNOWN;
163 static inline int fw_state_wait(struct fw_priv *fw_priv)
165 return __fw_state_wait_common(fw_priv, MAX_SCHEDULE_TIMEOUT);
168 static int fw_cache_piggyback_on_request(const char *name);
170 static struct fw_priv *__allocate_fw_priv(const char *fw_name,
171 struct firmware_cache *fwc,
177 struct fw_priv *fw_priv;
179 /* For a partial read, the buffer must be preallocated. */
180 if ((opt_flags & FW_OPT_PARTIAL) && !dbuf)
183 /* Only partial reads are allowed to use an offset. */
184 if (offset != 0 && !(opt_flags & FW_OPT_PARTIAL))
187 fw_priv = kzalloc(sizeof(*fw_priv), GFP_ATOMIC);
191 fw_priv->fw_name = kstrdup_const(fw_name, GFP_ATOMIC);
192 if (!fw_priv->fw_name) {
197 kref_init(&fw_priv->ref);
199 fw_priv->data = dbuf;
200 fw_priv->allocated_size = size;
201 fw_priv->offset = offset;
202 fw_priv->opt_flags = opt_flags;
203 fw_state_init(fw_priv);
204 #ifdef CONFIG_FW_LOADER_USER_HELPER
205 INIT_LIST_HEAD(&fw_priv->pending_list);
208 pr_debug("%s: fw-%s fw_priv=%p\n", __func__, fw_name, fw_priv);
213 static struct fw_priv *__lookup_fw_priv(const char *fw_name)
216 struct firmware_cache *fwc = &fw_cache;
218 list_for_each_entry(tmp, &fwc->head, list)
219 if (!strcmp(tmp->fw_name, fw_name))
224 /* Returns 1 for batching firmware requests with the same name */
225 static int alloc_lookup_fw_priv(const char *fw_name,
226 struct firmware_cache *fwc,
227 struct fw_priv **fw_priv,
235 spin_lock(&fwc->lock);
237 * Do not merge requests that are marked to be non-cached or
238 * are performing partial reads.
240 if (!(opt_flags & (FW_OPT_NOCACHE | FW_OPT_PARTIAL))) {
241 tmp = __lookup_fw_priv(fw_name);
244 spin_unlock(&fwc->lock);
246 pr_debug("batched request - sharing the same struct fw_priv and lookup for multiple requests\n");
251 tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size, offset, opt_flags);
253 INIT_LIST_HEAD(&tmp->list);
254 if (!(opt_flags & FW_OPT_NOCACHE))
255 list_add(&tmp->list, &fwc->head);
257 spin_unlock(&fwc->lock);
261 return tmp ? 0 : -ENOMEM;
264 static void __free_fw_priv(struct kref *ref)
265 __releases(&fwc->lock)
267 struct fw_priv *fw_priv = to_fw_priv(ref);
268 struct firmware_cache *fwc = fw_priv->fwc;
270 pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
271 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
272 (unsigned int)fw_priv->size);
274 list_del(&fw_priv->list);
275 spin_unlock(&fwc->lock);
277 if (fw_is_paged_buf(fw_priv))
278 fw_free_paged_buf(fw_priv);
279 else if (!fw_priv->allocated_size)
280 vfree(fw_priv->data);
282 kfree_const(fw_priv->fw_name);
286 static void free_fw_priv(struct fw_priv *fw_priv)
288 struct firmware_cache *fwc = fw_priv->fwc;
289 spin_lock(&fwc->lock);
290 if (!kref_put(&fw_priv->ref, __free_fw_priv))
291 spin_unlock(&fwc->lock);
294 #ifdef CONFIG_FW_LOADER_PAGED_BUF
295 bool fw_is_paged_buf(struct fw_priv *fw_priv)
297 return fw_priv->is_paged_buf;
300 void fw_free_paged_buf(struct fw_priv *fw_priv)
307 vunmap(fw_priv->data);
309 for (i = 0; i < fw_priv->nr_pages; i++)
310 __free_page(fw_priv->pages[i]);
311 kvfree(fw_priv->pages);
312 fw_priv->pages = NULL;
313 fw_priv->page_array_size = 0;
314 fw_priv->nr_pages = 0;
317 int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed)
319 /* If the array of pages is too small, grow it */
320 if (fw_priv->page_array_size < pages_needed) {
321 int new_array_size = max(pages_needed,
322 fw_priv->page_array_size * 2);
323 struct page **new_pages;
325 new_pages = kvmalloc_array(new_array_size, sizeof(void *),
329 memcpy(new_pages, fw_priv->pages,
330 fw_priv->page_array_size * sizeof(void *));
331 memset(&new_pages[fw_priv->page_array_size], 0, sizeof(void *) *
332 (new_array_size - fw_priv->page_array_size));
333 kvfree(fw_priv->pages);
334 fw_priv->pages = new_pages;
335 fw_priv->page_array_size = new_array_size;
338 while (fw_priv->nr_pages < pages_needed) {
339 fw_priv->pages[fw_priv->nr_pages] =
340 alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
342 if (!fw_priv->pages[fw_priv->nr_pages])
350 int fw_map_paged_buf(struct fw_priv *fw_priv)
352 /* one pages buffer should be mapped/unmapped only once */
356 vunmap(fw_priv->data);
357 fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages, 0,
367 * XZ-compressed firmware support
369 #ifdef CONFIG_FW_LOADER_COMPRESS
370 /* show an error and return the standard error code */
371 static int fw_decompress_xz_error(struct device *dev, enum xz_ret xz_ret)
373 if (xz_ret != XZ_STREAM_END) {
374 dev_warn(dev, "xz decompression failed (xz_ret=%d)\n", xz_ret);
375 return xz_ret == XZ_MEM_ERROR ? -ENOMEM : -EINVAL;
380 /* single-shot decompression onto the pre-allocated buffer */
381 static int fw_decompress_xz_single(struct device *dev, struct fw_priv *fw_priv,
382 size_t in_size, const void *in_buffer)
384 struct xz_dec *xz_dec;
385 struct xz_buf xz_buf;
388 xz_dec = xz_dec_init(XZ_SINGLE, (u32)-1);
392 xz_buf.in_size = in_size;
393 xz_buf.in = in_buffer;
395 xz_buf.out_size = fw_priv->allocated_size;
396 xz_buf.out = fw_priv->data;
399 xz_ret = xz_dec_run(xz_dec, &xz_buf);
402 fw_priv->size = xz_buf.out_pos;
403 return fw_decompress_xz_error(dev, xz_ret);
406 /* decompression on paged buffer and map it */
407 static int fw_decompress_xz_pages(struct device *dev, struct fw_priv *fw_priv,
408 size_t in_size, const void *in_buffer)
410 struct xz_dec *xz_dec;
411 struct xz_buf xz_buf;
416 xz_dec = xz_dec_init(XZ_DYNALLOC, (u32)-1);
420 xz_buf.in_size = in_size;
421 xz_buf.in = in_buffer;
424 fw_priv->is_paged_buf = true;
427 if (fw_grow_paged_buf(fw_priv, fw_priv->nr_pages + 1)) {
432 /* decompress onto the new allocated page */
433 page = fw_priv->pages[fw_priv->nr_pages - 1];
434 xz_buf.out = kmap(page);
436 xz_buf.out_size = PAGE_SIZE;
437 xz_ret = xz_dec_run(xz_dec, &xz_buf);
439 fw_priv->size += xz_buf.out_pos;
440 /* partial decompression means either end or error */
441 if (xz_buf.out_pos != PAGE_SIZE)
443 } while (xz_ret == XZ_OK);
445 err = fw_decompress_xz_error(dev, xz_ret);
447 err = fw_map_paged_buf(fw_priv);
454 static int fw_decompress_xz(struct device *dev, struct fw_priv *fw_priv,
455 size_t in_size, const void *in_buffer)
457 /* if the buffer is pre-allocated, we can perform in single-shot mode */
459 return fw_decompress_xz_single(dev, fw_priv, in_size, in_buffer);
461 return fw_decompress_xz_pages(dev, fw_priv, in_size, in_buffer);
463 #endif /* CONFIG_FW_LOADER_COMPRESS */
465 /* direct firmware loading support */
466 static char fw_path_para[256];
467 static const char * const fw_path[] = {
469 "/lib/firmware/updates/" UTS_RELEASE,
470 "/lib/firmware/updates",
471 "/lib/firmware/" UTS_RELEASE,
476 * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
477 * from kernel command line because firmware_class is generally built in
478 * kernel instead of module.
480 module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
481 MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
484 fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv,
486 int (*decompress)(struct device *dev,
487 struct fw_priv *fw_priv,
489 const void *in_buffer))
495 size_t msize = INT_MAX;
498 /* Already populated data member means we're loading into a buffer */
499 if (!decompress && fw_priv->data) {
500 buffer = fw_priv->data;
501 msize = fw_priv->allocated_size;
508 wait_for_initramfs();
509 for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
510 size_t file_size = 0;
511 size_t *file_size_ptr = NULL;
513 /* skip the unset customized path */
517 len = snprintf(path, PATH_MAX, "%s/%s%s",
518 fw_path[i], fw_priv->fw_name, suffix);
519 if (len >= PATH_MAX) {
527 * The total file size is only examined when doing a partial
528 * read; the "full read" case needs to fail if the whole
529 * firmware was not completely loaded.
531 if ((fw_priv->opt_flags & FW_OPT_PARTIAL) && buffer)
532 file_size_ptr = &file_size;
534 /* load firmware files from the mount namespace of init */
535 rc = kernel_read_file_from_path_initns(path, fw_priv->offset,
541 dev_warn(device, "loading %s failed with error %d\n",
544 dev_dbg(device, "loading %s failed for no such file or directory.\n",
551 dev_dbg(device, "Loading firmware from %s\n", path);
553 dev_dbg(device, "f/w decompressing %s\n",
555 rc = decompress(device, fw_priv, size, buffer);
556 /* discard the superfluous original content */
560 fw_free_paged_buf(fw_priv);
564 dev_dbg(device, "direct-loading %s\n",
567 fw_priv->data = buffer;
568 fw_priv->size = size;
570 fw_state_done(fw_priv);
578 /* firmware holds the ownership of pages */
579 static void firmware_free_data(const struct firmware *fw)
581 /* Loaded directly? */
586 free_fw_priv(fw->priv);
589 /* store the pages buffer info firmware from buf */
590 static void fw_set_page_data(struct fw_priv *fw_priv, struct firmware *fw)
593 fw->size = fw_priv->size;
594 fw->data = fw_priv->data;
596 pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
597 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
598 (unsigned int)fw_priv->size);
601 #ifdef CONFIG_FW_CACHE
602 static void fw_name_devm_release(struct device *dev, void *res)
604 struct fw_name_devm *fwn = res;
606 if (fwn->magic == (unsigned long)&fw_cache)
607 pr_debug("%s: fw_name-%s devm-%p released\n",
608 __func__, fwn->name, res);
609 kfree_const(fwn->name);
612 static int fw_devm_match(struct device *dev, void *res,
615 struct fw_name_devm *fwn = res;
617 return (fwn->magic == (unsigned long)&fw_cache) &&
618 !strcmp(fwn->name, match_data);
621 static struct fw_name_devm *fw_find_devm_name(struct device *dev,
624 struct fw_name_devm *fwn;
626 fwn = devres_find(dev, fw_name_devm_release,
627 fw_devm_match, (void *)name);
631 static bool fw_cache_is_setup(struct device *dev, const char *name)
633 struct fw_name_devm *fwn;
635 fwn = fw_find_devm_name(dev, name);
642 /* add firmware name into devres list */
643 static int fw_add_devm_name(struct device *dev, const char *name)
645 struct fw_name_devm *fwn;
647 if (fw_cache_is_setup(dev, name))
650 fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm),
654 fwn->name = kstrdup_const(name, GFP_KERNEL);
660 fwn->magic = (unsigned long)&fw_cache;
661 devres_add(dev, fwn);
666 static bool fw_cache_is_setup(struct device *dev, const char *name)
671 static int fw_add_devm_name(struct device *dev, const char *name)
677 int assign_fw(struct firmware *fw, struct device *device)
679 struct fw_priv *fw_priv = fw->priv;
682 mutex_lock(&fw_lock);
683 if (!fw_priv->size || fw_state_is_aborted(fw_priv)) {
684 mutex_unlock(&fw_lock);
689 * add firmware name into devres list so that we can auto cache
690 * and uncache firmware for device.
692 * device may has been deleted already, but the problem
693 * should be fixed in devres or driver core.
695 /* don't cache firmware handled without uevent */
696 if (device && (fw_priv->opt_flags & FW_OPT_UEVENT) &&
697 !(fw_priv->opt_flags & FW_OPT_NOCACHE)) {
698 ret = fw_add_devm_name(device, fw_priv->fw_name);
700 mutex_unlock(&fw_lock);
706 * After caching firmware image is started, let it piggyback
707 * on request firmware.
709 if (!(fw_priv->opt_flags & FW_OPT_NOCACHE) &&
710 fw_priv->fwc->state == FW_LOADER_START_CACHE) {
711 if (fw_cache_piggyback_on_request(fw_priv->fw_name))
712 kref_get(&fw_priv->ref);
715 /* pass the pages buffer to driver at the last minute */
716 fw_set_page_data(fw_priv, fw);
717 mutex_unlock(&fw_lock);
721 /* prepare firmware and firmware_buf structs;
722 * return 0 if a firmware is already assigned, 1 if need to load one,
723 * or a negative error code
726 _request_firmware_prepare(struct firmware **firmware_p, const char *name,
727 struct device *device, void *dbuf, size_t size,
728 size_t offset, u32 opt_flags)
730 struct firmware *firmware;
731 struct fw_priv *fw_priv;
734 *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
736 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
741 if (fw_get_builtin_firmware(firmware, name, dbuf, size)) {
742 dev_dbg(device, "using built-in %s\n", name);
743 return 0; /* assigned */
746 ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv, dbuf, size,
750 * bind with 'priv' now to avoid warning in failure path
751 * of requesting firmware.
753 firmware->priv = fw_priv;
756 ret = fw_state_wait(fw_priv);
758 fw_set_page_data(fw_priv, firmware);
759 return 0; /* assigned */
765 return 1; /* need to load */
769 * Batched requests need only one wake, we need to do this step last due to the
770 * fallback mechanism. The buf is protected with kref_get(), and it won't be
771 * released until the last user calls release_firmware().
773 * Failed batched requests are possible as well, in such cases we just share
774 * the struct fw_priv and won't release it until all requests are woken
775 * and have gone through this same path.
777 static void fw_abort_batch_reqs(struct firmware *fw)
779 struct fw_priv *fw_priv;
781 /* Loaded directly? */
782 if (!fw || !fw->priv)
786 mutex_lock(&fw_lock);
787 if (!fw_state_is_aborted(fw_priv))
788 fw_state_aborted(fw_priv);
789 mutex_unlock(&fw_lock);
792 /* called from request_firmware() and request_firmware_work_func() */
794 _request_firmware(const struct firmware **firmware_p, const char *name,
795 struct device *device, void *buf, size_t size,
796 size_t offset, u32 opt_flags)
798 struct firmware *fw = NULL;
799 bool nondirect = false;
805 if (!name || name[0] == '\0') {
810 ret = _request_firmware_prepare(&fw, name, device, buf, size,
812 if (ret <= 0) /* error or already assigned */
815 ret = fw_get_filesystem_firmware(device, fw->priv, "", NULL);
817 /* Only full reads can support decompression, platform, and sysfs. */
818 if (!(opt_flags & FW_OPT_PARTIAL))
821 #ifdef CONFIG_FW_LOADER_COMPRESS
822 if (ret == -ENOENT && nondirect)
823 ret = fw_get_filesystem_firmware(device, fw->priv, ".xz",
826 if (ret == -ENOENT && nondirect)
827 ret = firmware_fallback_platform(fw->priv);
830 if (!(opt_flags & FW_OPT_NO_WARN))
832 "Direct firmware load for %s failed with error %d\n",
835 ret = firmware_fallback_sysfs(fw, name, device,
838 ret = assign_fw(fw, device);
842 fw_abort_batch_reqs(fw);
843 release_firmware(fw);
852 * request_firmware() - send firmware request and wait for it
853 * @firmware_p: pointer to firmware image
854 * @name: name of firmware file
855 * @device: device for which firmware is being loaded
857 * @firmware_p will be used to return a firmware image by the name
858 * of @name for device @device.
860 * Should be called from user context where sleeping is allowed.
862 * @name will be used as $FIRMWARE in the uevent environment and
863 * should be distinctive enough not to be confused with any other
864 * firmware image for this or any other device.
866 * Caller must hold the reference count of @device.
868 * The function can be called safely inside device's suspend and
872 request_firmware(const struct firmware **firmware_p, const char *name,
873 struct device *device)
877 /* Need to pin this module until return */
878 __module_get(THIS_MODULE);
879 ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
881 module_put(THIS_MODULE);
884 EXPORT_SYMBOL(request_firmware);
887 * firmware_request_nowarn() - request for an optional fw module
888 * @firmware: pointer to firmware image
889 * @name: name of firmware file
890 * @device: device for which firmware is being loaded
892 * This function is similar in behaviour to request_firmware(), except it
893 * doesn't produce warning messages when the file is not found. The sysfs
894 * fallback mechanism is enabled if direct filesystem lookup fails. However,
895 * failures to find the firmware file with it are still suppressed. It is
896 * therefore up to the driver to check for the return value of this call and to
897 * decide when to inform the users of errors.
899 int firmware_request_nowarn(const struct firmware **firmware, const char *name,
900 struct device *device)
904 /* Need to pin this module until return */
905 __module_get(THIS_MODULE);
906 ret = _request_firmware(firmware, name, device, NULL, 0, 0,
907 FW_OPT_UEVENT | FW_OPT_NO_WARN);
908 module_put(THIS_MODULE);
911 EXPORT_SYMBOL_GPL(firmware_request_nowarn);
914 * request_firmware_direct() - load firmware directly without usermode helper
915 * @firmware_p: pointer to firmware image
916 * @name: name of firmware file
917 * @device: device for which firmware is being loaded
919 * This function works pretty much like request_firmware(), but this doesn't
920 * fall back to usermode helper even if the firmware couldn't be loaded
921 * directly from fs. Hence it's useful for loading optional firmwares, which
922 * aren't always present, without extra long timeouts of udev.
924 int request_firmware_direct(const struct firmware **firmware_p,
925 const char *name, struct device *device)
929 __module_get(THIS_MODULE);
930 ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
931 FW_OPT_UEVENT | FW_OPT_NO_WARN |
932 FW_OPT_NOFALLBACK_SYSFS);
933 module_put(THIS_MODULE);
936 EXPORT_SYMBOL_GPL(request_firmware_direct);
939 * firmware_request_platform() - request firmware with platform-fw fallback
940 * @firmware: pointer to firmware image
941 * @name: name of firmware file
942 * @device: device for which firmware is being loaded
944 * This function is similar in behaviour to request_firmware, except that if
945 * direct filesystem lookup fails, it will fallback to looking for a copy of the
946 * requested firmware embedded in the platform's main (e.g. UEFI) firmware.
948 int firmware_request_platform(const struct firmware **firmware,
949 const char *name, struct device *device)
953 /* Need to pin this module until return */
954 __module_get(THIS_MODULE);
955 ret = _request_firmware(firmware, name, device, NULL, 0, 0,
956 FW_OPT_UEVENT | FW_OPT_FALLBACK_PLATFORM);
957 module_put(THIS_MODULE);
960 EXPORT_SYMBOL_GPL(firmware_request_platform);
963 * firmware_request_cache() - cache firmware for suspend so resume can use it
964 * @name: name of firmware file
965 * @device: device for which firmware should be cached for
967 * There are some devices with an optimization that enables the device to not
968 * require loading firmware on system reboot. This optimization may still
969 * require the firmware present on resume from suspend. This routine can be
970 * used to ensure the firmware is present on resume from suspend in these
971 * situations. This helper is not compatible with drivers which use
972 * request_firmware_into_buf() or request_firmware_nowait() with no uevent set.
974 int firmware_request_cache(struct device *device, const char *name)
978 mutex_lock(&fw_lock);
979 ret = fw_add_devm_name(device, name);
980 mutex_unlock(&fw_lock);
984 EXPORT_SYMBOL_GPL(firmware_request_cache);
987 * request_firmware_into_buf() - load firmware into a previously allocated buffer
988 * @firmware_p: pointer to firmware image
989 * @name: name of firmware file
990 * @device: device for which firmware is being loaded and DMA region allocated
991 * @buf: address of buffer to load firmware into
992 * @size: size of buffer
994 * This function works pretty much like request_firmware(), but it doesn't
995 * allocate a buffer to hold the firmware data. Instead, the firmware
996 * is loaded directly into the buffer pointed to by @buf and the @firmware_p
997 * data member is pointed at @buf.
999 * This function doesn't cache firmware either.
1002 request_firmware_into_buf(const struct firmware **firmware_p, const char *name,
1003 struct device *device, void *buf, size_t size)
1007 if (fw_cache_is_setup(device, name))
1010 __module_get(THIS_MODULE);
1011 ret = _request_firmware(firmware_p, name, device, buf, size, 0,
1012 FW_OPT_UEVENT | FW_OPT_NOCACHE);
1013 module_put(THIS_MODULE);
1016 EXPORT_SYMBOL(request_firmware_into_buf);
1019 * request_partial_firmware_into_buf() - load partial firmware into a previously allocated buffer
1020 * @firmware_p: pointer to firmware image
1021 * @name: name of firmware file
1022 * @device: device for which firmware is being loaded and DMA region allocated
1023 * @buf: address of buffer to load firmware into
1024 * @size: size of buffer
1025 * @offset: offset into file to read
1027 * This function works pretty much like request_firmware_into_buf except
1028 * it allows a partial read of the file.
1031 request_partial_firmware_into_buf(const struct firmware **firmware_p,
1032 const char *name, struct device *device,
1033 void *buf, size_t size, size_t offset)
1037 if (fw_cache_is_setup(device, name))
1040 __module_get(THIS_MODULE);
1041 ret = _request_firmware(firmware_p, name, device, buf, size, offset,
1042 FW_OPT_UEVENT | FW_OPT_NOCACHE |
1044 module_put(THIS_MODULE);
1047 EXPORT_SYMBOL(request_partial_firmware_into_buf);
1050 * release_firmware() - release the resource associated with a firmware image
1051 * @fw: firmware resource to release
1053 void release_firmware(const struct firmware *fw)
1056 if (!fw_is_builtin_firmware(fw))
1057 firmware_free_data(fw);
1061 EXPORT_SYMBOL(release_firmware);
1064 struct firmware_work {
1065 struct work_struct work;
1066 struct module *module;
1068 struct device *device;
1070 void (*cont)(const struct firmware *fw, void *context);
1074 static void request_firmware_work_func(struct work_struct *work)
1076 struct firmware_work *fw_work;
1077 const struct firmware *fw;
1079 fw_work = container_of(work, struct firmware_work, work);
1081 _request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0, 0,
1082 fw_work->opt_flags);
1083 fw_work->cont(fw, fw_work->context);
1084 put_device(fw_work->device); /* taken in request_firmware_nowait() */
1086 module_put(fw_work->module);
1087 kfree_const(fw_work->name);
1092 * request_firmware_nowait() - asynchronous version of request_firmware
1093 * @module: module requesting the firmware
1094 * @uevent: sends uevent to copy the firmware image if this flag
1095 * is non-zero else the firmware copy must be done manually.
1096 * @name: name of firmware file
1097 * @device: device for which firmware is being loaded
1098 * @gfp: allocation flags
1099 * @context: will be passed over to @cont, and
1100 * @fw may be %NULL if firmware request fails.
1101 * @cont: function will be called asynchronously when the firmware
1104 * Caller must hold the reference count of @device.
1106 * Asynchronous variant of request_firmware() for user contexts:
1107 * - sleep for as small periods as possible since it may
1108 * increase kernel boot time of built-in device drivers
1109 * requesting firmware in their ->probe() methods, if
1110 * @gfp is GFP_KERNEL.
1112 * - can't sleep at all if @gfp is GFP_ATOMIC.
1115 request_firmware_nowait(
1116 struct module *module, bool uevent,
1117 const char *name, struct device *device, gfp_t gfp, void *context,
1118 void (*cont)(const struct firmware *fw, void *context))
1120 struct firmware_work *fw_work;
1122 fw_work = kzalloc(sizeof(struct firmware_work), gfp);
1126 fw_work->module = module;
1127 fw_work->name = kstrdup_const(name, gfp);
1128 if (!fw_work->name) {
1132 fw_work->device = device;
1133 fw_work->context = context;
1134 fw_work->cont = cont;
1135 fw_work->opt_flags = FW_OPT_NOWAIT |
1136 (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
1138 if (!uevent && fw_cache_is_setup(device, name)) {
1139 kfree_const(fw_work->name);
1144 if (!try_module_get(module)) {
1145 kfree_const(fw_work->name);
1150 get_device(fw_work->device);
1151 INIT_WORK(&fw_work->work, request_firmware_work_func);
1152 schedule_work(&fw_work->work);
1155 EXPORT_SYMBOL(request_firmware_nowait);
1157 #ifdef CONFIG_FW_CACHE
1158 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1161 * cache_firmware() - cache one firmware image in kernel memory space
1162 * @fw_name: the firmware image name
1164 * Cache firmware in kernel memory so that drivers can use it when
1165 * system isn't ready for them to request firmware image from userspace.
1166 * Once it returns successfully, driver can use request_firmware or its
1167 * nowait version to get the cached firmware without any interacting
1170 * Return 0 if the firmware image has been cached successfully
1171 * Return !0 otherwise
1174 static int cache_firmware(const char *fw_name)
1177 const struct firmware *fw;
1179 pr_debug("%s: %s\n", __func__, fw_name);
1181 ret = request_firmware(&fw, fw_name, NULL);
1185 pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1190 static struct fw_priv *lookup_fw_priv(const char *fw_name)
1192 struct fw_priv *tmp;
1193 struct firmware_cache *fwc = &fw_cache;
1195 spin_lock(&fwc->lock);
1196 tmp = __lookup_fw_priv(fw_name);
1197 spin_unlock(&fwc->lock);
1203 * uncache_firmware() - remove one cached firmware image
1204 * @fw_name: the firmware image name
1206 * Uncache one firmware image which has been cached successfully
1209 * Return 0 if the firmware cache has been removed successfully
1210 * Return !0 otherwise
1213 static int uncache_firmware(const char *fw_name)
1215 struct fw_priv *fw_priv;
1218 pr_debug("%s: %s\n", __func__, fw_name);
1220 if (fw_get_builtin_firmware(&fw, fw_name, NULL, 0))
1223 fw_priv = lookup_fw_priv(fw_name);
1225 free_fw_priv(fw_priv);
1232 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1234 struct fw_cache_entry *fce;
1236 fce = kzalloc(sizeof(*fce), GFP_ATOMIC);
1240 fce->name = kstrdup_const(name, GFP_ATOMIC);
1250 static int __fw_entry_found(const char *name)
1252 struct firmware_cache *fwc = &fw_cache;
1253 struct fw_cache_entry *fce;
1255 list_for_each_entry(fce, &fwc->fw_names, list) {
1256 if (!strcmp(fce->name, name))
1262 static int fw_cache_piggyback_on_request(const char *name)
1264 struct firmware_cache *fwc = &fw_cache;
1265 struct fw_cache_entry *fce;
1268 spin_lock(&fwc->name_lock);
1269 if (__fw_entry_found(name))
1272 fce = alloc_fw_cache_entry(name);
1275 list_add(&fce->list, &fwc->fw_names);
1276 pr_debug("%s: fw: %s\n", __func__, name);
1279 spin_unlock(&fwc->name_lock);
1283 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1285 kfree_const(fce->name);
1289 static void __async_dev_cache_fw_image(void *fw_entry,
1290 async_cookie_t cookie)
1292 struct fw_cache_entry *fce = fw_entry;
1293 struct firmware_cache *fwc = &fw_cache;
1296 ret = cache_firmware(fce->name);
1298 spin_lock(&fwc->name_lock);
1299 list_del(&fce->list);
1300 spin_unlock(&fwc->name_lock);
1302 free_fw_cache_entry(fce);
1306 /* called with dev->devres_lock held */
1307 static void dev_create_fw_entry(struct device *dev, void *res,
1310 struct fw_name_devm *fwn = res;
1311 const char *fw_name = fwn->name;
1312 struct list_head *head = data;
1313 struct fw_cache_entry *fce;
1315 fce = alloc_fw_cache_entry(fw_name);
1317 list_add(&fce->list, head);
1320 static int devm_name_match(struct device *dev, void *res,
1323 struct fw_name_devm *fwn = res;
1324 return (fwn->magic == (unsigned long)match_data);
1327 static void dev_cache_fw_image(struct device *dev, void *data)
1330 struct fw_cache_entry *fce;
1331 struct fw_cache_entry *fce_next;
1332 struct firmware_cache *fwc = &fw_cache;
1334 devres_for_each_res(dev, fw_name_devm_release,
1335 devm_name_match, &fw_cache,
1336 dev_create_fw_entry, &todo);
1338 list_for_each_entry_safe(fce, fce_next, &todo, list) {
1339 list_del(&fce->list);
1341 spin_lock(&fwc->name_lock);
1342 /* only one cache entry for one firmware */
1343 if (!__fw_entry_found(fce->name)) {
1344 list_add(&fce->list, &fwc->fw_names);
1346 free_fw_cache_entry(fce);
1349 spin_unlock(&fwc->name_lock);
1352 async_schedule_domain(__async_dev_cache_fw_image,
1358 static void __device_uncache_fw_images(void)
1360 struct firmware_cache *fwc = &fw_cache;
1361 struct fw_cache_entry *fce;
1363 spin_lock(&fwc->name_lock);
1364 while (!list_empty(&fwc->fw_names)) {
1365 fce = list_entry(fwc->fw_names.next,
1366 struct fw_cache_entry, list);
1367 list_del(&fce->list);
1368 spin_unlock(&fwc->name_lock);
1370 uncache_firmware(fce->name);
1371 free_fw_cache_entry(fce);
1373 spin_lock(&fwc->name_lock);
1375 spin_unlock(&fwc->name_lock);
1379 * device_cache_fw_images() - cache devices' firmware
1381 * If one device called request_firmware or its nowait version
1382 * successfully before, the firmware names are recored into the
1383 * device's devres link list, so device_cache_fw_images can call
1384 * cache_firmware() to cache these firmwares for the device,
1385 * then the device driver can load its firmwares easily at
1386 * time when system is not ready to complete loading firmware.
1388 static void device_cache_fw_images(void)
1390 struct firmware_cache *fwc = &fw_cache;
1393 pr_debug("%s\n", __func__);
1395 /* cancel uncache work */
1396 cancel_delayed_work_sync(&fwc->work);
1398 fw_fallback_set_cache_timeout();
1400 mutex_lock(&fw_lock);
1401 fwc->state = FW_LOADER_START_CACHE;
1402 dpm_for_each_dev(NULL, dev_cache_fw_image);
1403 mutex_unlock(&fw_lock);
1405 /* wait for completion of caching firmware for all devices */
1406 async_synchronize_full_domain(&fw_cache_domain);
1408 fw_fallback_set_default_timeout();
1412 * device_uncache_fw_images() - uncache devices' firmware
1414 * uncache all firmwares which have been cached successfully
1415 * by device_uncache_fw_images earlier
1417 static void device_uncache_fw_images(void)
1419 pr_debug("%s\n", __func__);
1420 __device_uncache_fw_images();
1423 static void device_uncache_fw_images_work(struct work_struct *work)
1425 device_uncache_fw_images();
1429 * device_uncache_fw_images_delay() - uncache devices firmwares
1430 * @delay: number of milliseconds to delay uncache device firmwares
1432 * uncache all devices's firmwares which has been cached successfully
1433 * by device_cache_fw_images after @delay milliseconds.
1435 static void device_uncache_fw_images_delay(unsigned long delay)
1437 queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1438 msecs_to_jiffies(delay));
1441 static int fw_pm_notify(struct notifier_block *notify_block,
1442 unsigned long mode, void *unused)
1445 case PM_HIBERNATION_PREPARE:
1446 case PM_SUSPEND_PREPARE:
1447 case PM_RESTORE_PREPARE:
1449 * kill pending fallback requests with a custom fallback
1450 * to avoid stalling suspend.
1452 kill_pending_fw_fallback_reqs(true);
1453 device_cache_fw_images();
1456 case PM_POST_SUSPEND:
1457 case PM_POST_HIBERNATION:
1458 case PM_POST_RESTORE:
1460 * In case that system sleep failed and syscore_suspend is
1463 mutex_lock(&fw_lock);
1464 fw_cache.state = FW_LOADER_NO_CACHE;
1465 mutex_unlock(&fw_lock);
1467 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1474 /* stop caching firmware once syscore_suspend is reached */
1475 static int fw_suspend(void)
1477 fw_cache.state = FW_LOADER_NO_CACHE;
1481 static struct syscore_ops fw_syscore_ops = {
1482 .suspend = fw_suspend,
1485 static int __init register_fw_pm_ops(void)
1489 spin_lock_init(&fw_cache.name_lock);
1490 INIT_LIST_HEAD(&fw_cache.fw_names);
1492 INIT_DELAYED_WORK(&fw_cache.work,
1493 device_uncache_fw_images_work);
1495 fw_cache.pm_notify.notifier_call = fw_pm_notify;
1496 ret = register_pm_notifier(&fw_cache.pm_notify);
1500 register_syscore_ops(&fw_syscore_ops);
1505 static inline void unregister_fw_pm_ops(void)
1507 unregister_syscore_ops(&fw_syscore_ops);
1508 unregister_pm_notifier(&fw_cache.pm_notify);
1511 static int fw_cache_piggyback_on_request(const char *name)
1515 static inline int register_fw_pm_ops(void)
1519 static inline void unregister_fw_pm_ops(void)
1524 static void __init fw_cache_init(void)
1526 spin_lock_init(&fw_cache.lock);
1527 INIT_LIST_HEAD(&fw_cache.head);
1528 fw_cache.state = FW_LOADER_NO_CACHE;
1531 static int fw_shutdown_notify(struct notifier_block *unused1,
1532 unsigned long unused2, void *unused3)
1535 * Kill all pending fallback requests to avoid both stalling shutdown,
1536 * and avoid a deadlock with the usermode_lock.
1538 kill_pending_fw_fallback_reqs(false);
1543 static struct notifier_block fw_shutdown_nb = {
1544 .notifier_call = fw_shutdown_notify,
1547 static int __init firmware_class_init(void)
1551 /* No need to unfold these on exit */
1554 ret = register_fw_pm_ops();
1558 ret = register_reboot_notifier(&fw_shutdown_nb);
1562 return register_sysfs_loader();
1565 unregister_fw_pm_ops();
1569 static void __exit firmware_class_exit(void)
1571 unregister_fw_pm_ops();
1572 unregister_reboot_notifier(&fw_shutdown_nb);
1573 unregister_sysfs_loader();
1576 fs_initcall(firmware_class_init);
1577 module_exit(firmware_class_exit);