Loading...
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * main.c - Multi purpose firmware loading support
4 *
5 * Copyright (c) 2003 Manuel Estrada Sainz
6 *
7 * Please see Documentation/driver-api/firmware/ for more information.
8 *
9 */
10
11#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12
13#include <linux/capability.h>
14#include <linux/device.h>
15#include <linux/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>
29#include <linux/fs.h>
30#include <linux/async.h>
31#include <linux/pm.h>
32#include <linux/suspend.h>
33#include <linux/syscore_ops.h>
34#include <linux/reboot.h>
35#include <linux/security.h>
36#include <linux/xz.h>
37
38#include <generated/utsrelease.h>
39
40#include "../base.h"
41#include "firmware.h"
42#include "fallback.h"
43
44MODULE_AUTHOR("Manuel Estrada Sainz");
45MODULE_DESCRIPTION("Multi purpose firmware loading support");
46MODULE_LICENSE("GPL");
47
48struct firmware_cache {
49 /* firmware_buf instance will be added into the below list */
50 spinlock_t lock;
51 struct list_head head;
52 int state;
53
54#ifdef CONFIG_FW_CACHE
55 /*
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
59 * before.
60 */
61 spinlock_t name_lock;
62 struct list_head fw_names;
63
64 struct delayed_work work;
65
66 struct notifier_block pm_notify;
67#endif
68};
69
70struct fw_cache_entry {
71 struct list_head list;
72 const char *name;
73};
74
75struct fw_name_devm {
76 unsigned long magic;
77 const char *name;
78};
79
80static inline struct fw_priv *to_fw_priv(struct kref *ref)
81{
82 return container_of(ref, struct fw_priv, ref);
83}
84
85#define FW_LOADER_NO_CACHE 0
86#define FW_LOADER_START_CACHE 1
87
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 */
90DEFINE_MUTEX(fw_lock);
91
92static struct firmware_cache fw_cache;
93
94/* Builtin firmware support */
95
96#ifdef CONFIG_FW_LOADER
97
98extern struct builtin_fw __start_builtin_fw[];
99extern struct builtin_fw __end_builtin_fw[];
100
101static void fw_copy_to_prealloc_buf(struct firmware *fw,
102 void *buf, size_t size)
103{
104 if (!buf || size < fw->size)
105 return;
106 memcpy(buf, fw->data, fw->size);
107}
108
109static bool fw_get_builtin_firmware(struct firmware *fw, const char *name,
110 void *buf, size_t size)
111{
112 struct builtin_fw *b_fw;
113
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);
119
120 return true;
121 }
122 }
123
124 return false;
125}
126
127static bool fw_is_builtin_firmware(const struct firmware *fw)
128{
129 struct builtin_fw *b_fw;
130
131 for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
132 if (fw->data == b_fw->data)
133 return true;
134
135 return false;
136}
137
138#else /* Module case - no builtin firmware support */
139
140static inline bool fw_get_builtin_firmware(struct firmware *fw,
141 const char *name, void *buf,
142 size_t size)
143{
144 return false;
145}
146
147static inline bool fw_is_builtin_firmware(const struct firmware *fw)
148{
149 return false;
150}
151#endif
152
153static void fw_state_init(struct fw_priv *fw_priv)
154{
155 struct fw_state *fw_st = &fw_priv->fw_st;
156
157 init_completion(&fw_st->completion);
158 fw_st->status = FW_STATUS_UNKNOWN;
159}
160
161static inline int fw_state_wait(struct fw_priv *fw_priv)
162{
163 return __fw_state_wait_common(fw_priv, MAX_SCHEDULE_TIMEOUT);
164}
165
166static int fw_cache_piggyback_on_request(const char *name);
167
168static struct fw_priv *__allocate_fw_priv(const char *fw_name,
169 struct firmware_cache *fwc,
170 void *dbuf, size_t size)
171{
172 struct fw_priv *fw_priv;
173
174 fw_priv = kzalloc(sizeof(*fw_priv), GFP_ATOMIC);
175 if (!fw_priv)
176 return NULL;
177
178 fw_priv->fw_name = kstrdup_const(fw_name, GFP_ATOMIC);
179 if (!fw_priv->fw_name) {
180 kfree(fw_priv);
181 return NULL;
182 }
183
184 kref_init(&fw_priv->ref);
185 fw_priv->fwc = fwc;
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);
191#endif
192
193 pr_debug("%s: fw-%s fw_priv=%p\n", __func__, fw_name, fw_priv);
194
195 return fw_priv;
196}
197
198static struct fw_priv *__lookup_fw_priv(const char *fw_name)
199{
200 struct fw_priv *tmp;
201 struct firmware_cache *fwc = &fw_cache;
202
203 list_for_each_entry(tmp, &fwc->head, list)
204 if (!strcmp(tmp->fw_name, fw_name))
205 return tmp;
206 return NULL;
207}
208
209/* Returns 1 for batching firmware requests with the same name */
210static 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, u32 opt_flags)
214{
215 struct fw_priv *tmp;
216
217 spin_lock(&fwc->lock);
218 if (!(opt_flags & FW_OPT_NOCACHE)) {
219 tmp = __lookup_fw_priv(fw_name);
220 if (tmp) {
221 kref_get(&tmp->ref);
222 spin_unlock(&fwc->lock);
223 *fw_priv = tmp;
224 pr_debug("batched request - sharing the same struct fw_priv and lookup for multiple requests\n");
225 return 1;
226 }
227 }
228
229 tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size);
230 if (tmp) {
231 INIT_LIST_HEAD(&tmp->list);
232 if (!(opt_flags & FW_OPT_NOCACHE))
233 list_add(&tmp->list, &fwc->head);
234 }
235 spin_unlock(&fwc->lock);
236
237 *fw_priv = tmp;
238
239 return tmp ? 0 : -ENOMEM;
240}
241
242static void __free_fw_priv(struct kref *ref)
243 __releases(&fwc->lock)
244{
245 struct fw_priv *fw_priv = to_fw_priv(ref);
246 struct firmware_cache *fwc = fw_priv->fwc;
247
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);
251
252 list_del(&fw_priv->list);
253 spin_unlock(&fwc->lock);
254
255 if (fw_is_paged_buf(fw_priv))
256 fw_free_paged_buf(fw_priv);
257 else if (!fw_priv->allocated_size)
258 vfree(fw_priv->data);
259
260 kfree_const(fw_priv->fw_name);
261 kfree(fw_priv);
262}
263
264static void free_fw_priv(struct fw_priv *fw_priv)
265{
266 struct firmware_cache *fwc = fw_priv->fwc;
267 spin_lock(&fwc->lock);
268 if (!kref_put(&fw_priv->ref, __free_fw_priv))
269 spin_unlock(&fwc->lock);
270}
271
272#ifdef CONFIG_FW_LOADER_PAGED_BUF
273bool fw_is_paged_buf(struct fw_priv *fw_priv)
274{
275 return fw_priv->is_paged_buf;
276}
277
278void fw_free_paged_buf(struct fw_priv *fw_priv)
279{
280 int i;
281
282 if (!fw_priv->pages)
283 return;
284
285 vunmap(fw_priv->data);
286
287 for (i = 0; i < fw_priv->nr_pages; i++)
288 __free_page(fw_priv->pages[i]);
289 kvfree(fw_priv->pages);
290 fw_priv->pages = NULL;
291 fw_priv->page_array_size = 0;
292 fw_priv->nr_pages = 0;
293}
294
295int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed)
296{
297 /* If the array of pages is too small, grow it */
298 if (fw_priv->page_array_size < pages_needed) {
299 int new_array_size = max(pages_needed,
300 fw_priv->page_array_size * 2);
301 struct page **new_pages;
302
303 new_pages = kvmalloc_array(new_array_size, sizeof(void *),
304 GFP_KERNEL);
305 if (!new_pages)
306 return -ENOMEM;
307 memcpy(new_pages, fw_priv->pages,
308 fw_priv->page_array_size * sizeof(void *));
309 memset(&new_pages[fw_priv->page_array_size], 0, sizeof(void *) *
310 (new_array_size - fw_priv->page_array_size));
311 kvfree(fw_priv->pages);
312 fw_priv->pages = new_pages;
313 fw_priv->page_array_size = new_array_size;
314 }
315
316 while (fw_priv->nr_pages < pages_needed) {
317 fw_priv->pages[fw_priv->nr_pages] =
318 alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
319
320 if (!fw_priv->pages[fw_priv->nr_pages])
321 return -ENOMEM;
322 fw_priv->nr_pages++;
323 }
324
325 return 0;
326}
327
328int fw_map_paged_buf(struct fw_priv *fw_priv)
329{
330 /* one pages buffer should be mapped/unmapped only once */
331 if (!fw_priv->pages)
332 return 0;
333
334 vunmap(fw_priv->data);
335 fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages, 0,
336 PAGE_KERNEL_RO);
337 if (!fw_priv->data)
338 return -ENOMEM;
339
340 return 0;
341}
342#endif
343
344/*
345 * XZ-compressed firmware support
346 */
347#ifdef CONFIG_FW_LOADER_COMPRESS
348/* show an error and return the standard error code */
349static int fw_decompress_xz_error(struct device *dev, enum xz_ret xz_ret)
350{
351 if (xz_ret != XZ_STREAM_END) {
352 dev_warn(dev, "xz decompression failed (xz_ret=%d)\n", xz_ret);
353 return xz_ret == XZ_MEM_ERROR ? -ENOMEM : -EINVAL;
354 }
355 return 0;
356}
357
358/* single-shot decompression onto the pre-allocated buffer */
359static int fw_decompress_xz_single(struct device *dev, struct fw_priv *fw_priv,
360 size_t in_size, const void *in_buffer)
361{
362 struct xz_dec *xz_dec;
363 struct xz_buf xz_buf;
364 enum xz_ret xz_ret;
365
366 xz_dec = xz_dec_init(XZ_SINGLE, (u32)-1);
367 if (!xz_dec)
368 return -ENOMEM;
369
370 xz_buf.in_size = in_size;
371 xz_buf.in = in_buffer;
372 xz_buf.in_pos = 0;
373 xz_buf.out_size = fw_priv->allocated_size;
374 xz_buf.out = fw_priv->data;
375 xz_buf.out_pos = 0;
376
377 xz_ret = xz_dec_run(xz_dec, &xz_buf);
378 xz_dec_end(xz_dec);
379
380 fw_priv->size = xz_buf.out_pos;
381 return fw_decompress_xz_error(dev, xz_ret);
382}
383
384/* decompression on paged buffer and map it */
385static int fw_decompress_xz_pages(struct device *dev, struct fw_priv *fw_priv,
386 size_t in_size, const void *in_buffer)
387{
388 struct xz_dec *xz_dec;
389 struct xz_buf xz_buf;
390 enum xz_ret xz_ret;
391 struct page *page;
392 int err = 0;
393
394 xz_dec = xz_dec_init(XZ_DYNALLOC, (u32)-1);
395 if (!xz_dec)
396 return -ENOMEM;
397
398 xz_buf.in_size = in_size;
399 xz_buf.in = in_buffer;
400 xz_buf.in_pos = 0;
401
402 fw_priv->is_paged_buf = true;
403 fw_priv->size = 0;
404 do {
405 if (fw_grow_paged_buf(fw_priv, fw_priv->nr_pages + 1)) {
406 err = -ENOMEM;
407 goto out;
408 }
409
410 /* decompress onto the new allocated page */
411 page = fw_priv->pages[fw_priv->nr_pages - 1];
412 xz_buf.out = kmap(page);
413 xz_buf.out_pos = 0;
414 xz_buf.out_size = PAGE_SIZE;
415 xz_ret = xz_dec_run(xz_dec, &xz_buf);
416 kunmap(page);
417 fw_priv->size += xz_buf.out_pos;
418 /* partial decompression means either end or error */
419 if (xz_buf.out_pos != PAGE_SIZE)
420 break;
421 } while (xz_ret == XZ_OK);
422
423 err = fw_decompress_xz_error(dev, xz_ret);
424 if (!err)
425 err = fw_map_paged_buf(fw_priv);
426
427 out:
428 xz_dec_end(xz_dec);
429 return err;
430}
431
432static int fw_decompress_xz(struct device *dev, struct fw_priv *fw_priv,
433 size_t in_size, const void *in_buffer)
434{
435 /* if the buffer is pre-allocated, we can perform in single-shot mode */
436 if (fw_priv->data)
437 return fw_decompress_xz_single(dev, fw_priv, in_size, in_buffer);
438 else
439 return fw_decompress_xz_pages(dev, fw_priv, in_size, in_buffer);
440}
441#endif /* CONFIG_FW_LOADER_COMPRESS */
442
443/* direct firmware loading support */
444static char fw_path_para[256];
445static const char * const fw_path[] = {
446 fw_path_para,
447 "/lib/firmware/updates/" UTS_RELEASE,
448 "/lib/firmware/updates",
449 "/lib/firmware/" UTS_RELEASE,
450 "/lib/firmware"
451};
452
453/*
454 * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
455 * from kernel command line because firmware_class is generally built in
456 * kernel instead of module.
457 */
458module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
459MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
460
461static int
462fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv,
463 const char *suffix,
464 int (*decompress)(struct device *dev,
465 struct fw_priv *fw_priv,
466 size_t in_size,
467 const void *in_buffer))
468{
469 loff_t size;
470 int i, len;
471 int rc = -ENOENT;
472 char *path;
473 enum kernel_read_file_id id = READING_FIRMWARE;
474 size_t msize = INT_MAX;
475 void *buffer = NULL;
476
477 /* Already populated data member means we're loading into a buffer */
478 if (!decompress && fw_priv->data) {
479 buffer = fw_priv->data;
480 id = READING_FIRMWARE_PREALLOC_BUFFER;
481 msize = fw_priv->allocated_size;
482 }
483
484 path = __getname();
485 if (!path)
486 return -ENOMEM;
487
488 for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
489 /* skip the unset customized path */
490 if (!fw_path[i][0])
491 continue;
492
493 len = snprintf(path, PATH_MAX, "%s/%s%s",
494 fw_path[i], fw_priv->fw_name, suffix);
495 if (len >= PATH_MAX) {
496 rc = -ENAMETOOLONG;
497 break;
498 }
499
500 fw_priv->size = 0;
501
502 /* load firmware files from the mount namespace of init */
503 rc = kernel_read_file_from_path_initns(path, &buffer,
504 &size, msize, id);
505 if (rc) {
506 if (rc != -ENOENT)
507 dev_warn(device, "loading %s failed with error %d\n",
508 path, rc);
509 else
510 dev_dbg(device, "loading %s failed for no such file or directory.\n",
511 path);
512 continue;
513 }
514 dev_dbg(device, "Loading firmware from %s\n", path);
515 if (decompress) {
516 dev_dbg(device, "f/w decompressing %s\n",
517 fw_priv->fw_name);
518 rc = decompress(device, fw_priv, size, buffer);
519 /* discard the superfluous original content */
520 vfree(buffer);
521 buffer = NULL;
522 if (rc) {
523 fw_free_paged_buf(fw_priv);
524 continue;
525 }
526 } else {
527 dev_dbg(device, "direct-loading %s\n",
528 fw_priv->fw_name);
529 if (!fw_priv->data)
530 fw_priv->data = buffer;
531 fw_priv->size = size;
532 }
533 fw_state_done(fw_priv);
534 break;
535 }
536 __putname(path);
537
538 return rc;
539}
540
541/* firmware holds the ownership of pages */
542static void firmware_free_data(const struct firmware *fw)
543{
544 /* Loaded directly? */
545 if (!fw->priv) {
546 vfree(fw->data);
547 return;
548 }
549 free_fw_priv(fw->priv);
550}
551
552/* store the pages buffer info firmware from buf */
553static void fw_set_page_data(struct fw_priv *fw_priv, struct firmware *fw)
554{
555 fw->priv = fw_priv;
556 fw->size = fw_priv->size;
557 fw->data = fw_priv->data;
558
559 pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
560 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
561 (unsigned int)fw_priv->size);
562}
563
564#ifdef CONFIG_FW_CACHE
565static void fw_name_devm_release(struct device *dev, void *res)
566{
567 struct fw_name_devm *fwn = res;
568
569 if (fwn->magic == (unsigned long)&fw_cache)
570 pr_debug("%s: fw_name-%s devm-%p released\n",
571 __func__, fwn->name, res);
572 kfree_const(fwn->name);
573}
574
575static int fw_devm_match(struct device *dev, void *res,
576 void *match_data)
577{
578 struct fw_name_devm *fwn = res;
579
580 return (fwn->magic == (unsigned long)&fw_cache) &&
581 !strcmp(fwn->name, match_data);
582}
583
584static struct fw_name_devm *fw_find_devm_name(struct device *dev,
585 const char *name)
586{
587 struct fw_name_devm *fwn;
588
589 fwn = devres_find(dev, fw_name_devm_release,
590 fw_devm_match, (void *)name);
591 return fwn;
592}
593
594static bool fw_cache_is_setup(struct device *dev, const char *name)
595{
596 struct fw_name_devm *fwn;
597
598 fwn = fw_find_devm_name(dev, name);
599 if (fwn)
600 return true;
601
602 return false;
603}
604
605/* add firmware name into devres list */
606static int fw_add_devm_name(struct device *dev, const char *name)
607{
608 struct fw_name_devm *fwn;
609
610 if (fw_cache_is_setup(dev, name))
611 return 0;
612
613 fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm),
614 GFP_KERNEL);
615 if (!fwn)
616 return -ENOMEM;
617 fwn->name = kstrdup_const(name, GFP_KERNEL);
618 if (!fwn->name) {
619 devres_free(fwn);
620 return -ENOMEM;
621 }
622
623 fwn->magic = (unsigned long)&fw_cache;
624 devres_add(dev, fwn);
625
626 return 0;
627}
628#else
629static bool fw_cache_is_setup(struct device *dev, const char *name)
630{
631 return false;
632}
633
634static int fw_add_devm_name(struct device *dev, const char *name)
635{
636 return 0;
637}
638#endif
639
640int assign_fw(struct firmware *fw, struct device *device, u32 opt_flags)
641{
642 struct fw_priv *fw_priv = fw->priv;
643 int ret;
644
645 mutex_lock(&fw_lock);
646 if (!fw_priv->size || fw_state_is_aborted(fw_priv)) {
647 mutex_unlock(&fw_lock);
648 return -ENOENT;
649 }
650
651 /*
652 * add firmware name into devres list so that we can auto cache
653 * and uncache firmware for device.
654 *
655 * device may has been deleted already, but the problem
656 * should be fixed in devres or driver core.
657 */
658 /* don't cache firmware handled without uevent */
659 if (device && (opt_flags & FW_OPT_UEVENT) &&
660 !(opt_flags & FW_OPT_NOCACHE)) {
661 ret = fw_add_devm_name(device, fw_priv->fw_name);
662 if (ret) {
663 mutex_unlock(&fw_lock);
664 return ret;
665 }
666 }
667
668 /*
669 * After caching firmware image is started, let it piggyback
670 * on request firmware.
671 */
672 if (!(opt_flags & FW_OPT_NOCACHE) &&
673 fw_priv->fwc->state == FW_LOADER_START_CACHE) {
674 if (fw_cache_piggyback_on_request(fw_priv->fw_name))
675 kref_get(&fw_priv->ref);
676 }
677
678 /* pass the pages buffer to driver at the last minute */
679 fw_set_page_data(fw_priv, fw);
680 mutex_unlock(&fw_lock);
681 return 0;
682}
683
684/* prepare firmware and firmware_buf structs;
685 * return 0 if a firmware is already assigned, 1 if need to load one,
686 * or a negative error code
687 */
688static int
689_request_firmware_prepare(struct firmware **firmware_p, const char *name,
690 struct device *device, void *dbuf, size_t size,
691 u32 opt_flags)
692{
693 struct firmware *firmware;
694 struct fw_priv *fw_priv;
695 int ret;
696
697 *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
698 if (!firmware) {
699 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
700 __func__);
701 return -ENOMEM;
702 }
703
704 if (fw_get_builtin_firmware(firmware, name, dbuf, size)) {
705 dev_dbg(device, "using built-in %s\n", name);
706 return 0; /* assigned */
707 }
708
709 ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv, dbuf, size,
710 opt_flags);
711
712 /*
713 * bind with 'priv' now to avoid warning in failure path
714 * of requesting firmware.
715 */
716 firmware->priv = fw_priv;
717
718 if (ret > 0) {
719 ret = fw_state_wait(fw_priv);
720 if (!ret) {
721 fw_set_page_data(fw_priv, firmware);
722 return 0; /* assigned */
723 }
724 }
725
726 if (ret < 0)
727 return ret;
728 return 1; /* need to load */
729}
730
731/*
732 * Batched requests need only one wake, we need to do this step last due to the
733 * fallback mechanism. The buf is protected with kref_get(), and it won't be
734 * released until the last user calls release_firmware().
735 *
736 * Failed batched requests are possible as well, in such cases we just share
737 * the struct fw_priv and won't release it until all requests are woken
738 * and have gone through this same path.
739 */
740static void fw_abort_batch_reqs(struct firmware *fw)
741{
742 struct fw_priv *fw_priv;
743
744 /* Loaded directly? */
745 if (!fw || !fw->priv)
746 return;
747
748 fw_priv = fw->priv;
749 if (!fw_state_is_aborted(fw_priv))
750 fw_state_aborted(fw_priv);
751}
752
753/* called from request_firmware() and request_firmware_work_func() */
754static int
755_request_firmware(const struct firmware **firmware_p, const char *name,
756 struct device *device, void *buf, size_t size,
757 u32 opt_flags)
758{
759 struct firmware *fw = NULL;
760 int ret;
761
762 if (!firmware_p)
763 return -EINVAL;
764
765 if (!name || name[0] == '\0') {
766 ret = -EINVAL;
767 goto out;
768 }
769
770 ret = _request_firmware_prepare(&fw, name, device, buf, size,
771 opt_flags);
772 if (ret <= 0) /* error or already assigned */
773 goto out;
774
775 ret = fw_get_filesystem_firmware(device, fw->priv, "", NULL);
776#ifdef CONFIG_FW_LOADER_COMPRESS
777 if (ret == -ENOENT)
778 ret = fw_get_filesystem_firmware(device, fw->priv, ".xz",
779 fw_decompress_xz);
780#endif
781
782 if (ret == -ENOENT)
783 ret = firmware_fallback_platform(fw->priv, opt_flags);
784
785 if (ret) {
786 if (!(opt_flags & FW_OPT_NO_WARN))
787 dev_warn(device,
788 "Direct firmware load for %s failed with error %d\n",
789 name, ret);
790 ret = firmware_fallback_sysfs(fw, name, device, opt_flags, ret);
791 } else
792 ret = assign_fw(fw, device, opt_flags);
793
794 out:
795 if (ret < 0) {
796 fw_abort_batch_reqs(fw);
797 release_firmware(fw);
798 fw = NULL;
799 }
800
801 *firmware_p = fw;
802 return ret;
803}
804
805/**
806 * request_firmware() - send firmware request and wait for it
807 * @firmware_p: pointer to firmware image
808 * @name: name of firmware file
809 * @device: device for which firmware is being loaded
810 *
811 * @firmware_p will be used to return a firmware image by the name
812 * of @name for device @device.
813 *
814 * Should be called from user context where sleeping is allowed.
815 *
816 * @name will be used as $FIRMWARE in the uevent environment and
817 * should be distinctive enough not to be confused with any other
818 * firmware image for this or any other device.
819 *
820 * Caller must hold the reference count of @device.
821 *
822 * The function can be called safely inside device's suspend and
823 * resume callback.
824 **/
825int
826request_firmware(const struct firmware **firmware_p, const char *name,
827 struct device *device)
828{
829 int ret;
830
831 /* Need to pin this module until return */
832 __module_get(THIS_MODULE);
833 ret = _request_firmware(firmware_p, name, device, NULL, 0,
834 FW_OPT_UEVENT);
835 module_put(THIS_MODULE);
836 return ret;
837}
838EXPORT_SYMBOL(request_firmware);
839
840/**
841 * firmware_request_nowarn() - request for an optional fw module
842 * @firmware: pointer to firmware image
843 * @name: name of firmware file
844 * @device: device for which firmware is being loaded
845 *
846 * This function is similar in behaviour to request_firmware(), except it
847 * doesn't produce warning messages when the file is not found. The sysfs
848 * fallback mechanism is enabled if direct filesystem lookup fails. However,
849 * failures to find the firmware file with it are still suppressed. It is
850 * therefore up to the driver to check for the return value of this call and to
851 * decide when to inform the users of errors.
852 **/
853int firmware_request_nowarn(const struct firmware **firmware, const char *name,
854 struct device *device)
855{
856 int ret;
857
858 /* Need to pin this module until return */
859 __module_get(THIS_MODULE);
860 ret = _request_firmware(firmware, name, device, NULL, 0,
861 FW_OPT_UEVENT | FW_OPT_NO_WARN);
862 module_put(THIS_MODULE);
863 return ret;
864}
865EXPORT_SYMBOL_GPL(firmware_request_nowarn);
866
867/**
868 * request_firmware_direct() - load firmware directly without usermode helper
869 * @firmware_p: pointer to firmware image
870 * @name: name of firmware file
871 * @device: device for which firmware is being loaded
872 *
873 * This function works pretty much like request_firmware(), but this doesn't
874 * fall back to usermode helper even if the firmware couldn't be loaded
875 * directly from fs. Hence it's useful for loading optional firmwares, which
876 * aren't always present, without extra long timeouts of udev.
877 **/
878int request_firmware_direct(const struct firmware **firmware_p,
879 const char *name, struct device *device)
880{
881 int ret;
882
883 __module_get(THIS_MODULE);
884 ret = _request_firmware(firmware_p, name, device, NULL, 0,
885 FW_OPT_UEVENT | FW_OPT_NO_WARN |
886 FW_OPT_NOFALLBACK_SYSFS);
887 module_put(THIS_MODULE);
888 return ret;
889}
890EXPORT_SYMBOL_GPL(request_firmware_direct);
891
892/**
893 * firmware_request_platform() - request firmware with platform-fw fallback
894 * @firmware: pointer to firmware image
895 * @name: name of firmware file
896 * @device: device for which firmware is being loaded
897 *
898 * This function is similar in behaviour to request_firmware, except that if
899 * direct filesystem lookup fails, it will fallback to looking for a copy of the
900 * requested firmware embedded in the platform's main (e.g. UEFI) firmware.
901 **/
902int firmware_request_platform(const struct firmware **firmware,
903 const char *name, struct device *device)
904{
905 int ret;
906
907 /* Need to pin this module until return */
908 __module_get(THIS_MODULE);
909 ret = _request_firmware(firmware, name, device, NULL, 0,
910 FW_OPT_UEVENT | FW_OPT_FALLBACK_PLATFORM);
911 module_put(THIS_MODULE);
912 return ret;
913}
914EXPORT_SYMBOL_GPL(firmware_request_platform);
915
916/**
917 * firmware_request_cache() - cache firmware for suspend so resume can use it
918 * @name: name of firmware file
919 * @device: device for which firmware should be cached for
920 *
921 * There are some devices with an optimization that enables the device to not
922 * require loading firmware on system reboot. This optimization may still
923 * require the firmware present on resume from suspend. This routine can be
924 * used to ensure the firmware is present on resume from suspend in these
925 * situations. This helper is not compatible with drivers which use
926 * request_firmware_into_buf() or request_firmware_nowait() with no uevent set.
927 **/
928int firmware_request_cache(struct device *device, const char *name)
929{
930 int ret;
931
932 mutex_lock(&fw_lock);
933 ret = fw_add_devm_name(device, name);
934 mutex_unlock(&fw_lock);
935
936 return ret;
937}
938EXPORT_SYMBOL_GPL(firmware_request_cache);
939
940/**
941 * request_firmware_into_buf() - load firmware into a previously allocated buffer
942 * @firmware_p: pointer to firmware image
943 * @name: name of firmware file
944 * @device: device for which firmware is being loaded and DMA region allocated
945 * @buf: address of buffer to load firmware into
946 * @size: size of buffer
947 *
948 * This function works pretty much like request_firmware(), but it doesn't
949 * allocate a buffer to hold the firmware data. Instead, the firmware
950 * is loaded directly into the buffer pointed to by @buf and the @firmware_p
951 * data member is pointed at @buf.
952 *
953 * This function doesn't cache firmware either.
954 */
955int
956request_firmware_into_buf(const struct firmware **firmware_p, const char *name,
957 struct device *device, void *buf, size_t size)
958{
959 int ret;
960
961 if (fw_cache_is_setup(device, name))
962 return -EOPNOTSUPP;
963
964 __module_get(THIS_MODULE);
965 ret = _request_firmware(firmware_p, name, device, buf, size,
966 FW_OPT_UEVENT | FW_OPT_NOCACHE);
967 module_put(THIS_MODULE);
968 return ret;
969}
970EXPORT_SYMBOL(request_firmware_into_buf);
971
972/**
973 * release_firmware() - release the resource associated with a firmware image
974 * @fw: firmware resource to release
975 **/
976void release_firmware(const struct firmware *fw)
977{
978 if (fw) {
979 if (!fw_is_builtin_firmware(fw))
980 firmware_free_data(fw);
981 kfree(fw);
982 }
983}
984EXPORT_SYMBOL(release_firmware);
985
986/* Async support */
987struct firmware_work {
988 struct work_struct work;
989 struct module *module;
990 const char *name;
991 struct device *device;
992 void *context;
993 void (*cont)(const struct firmware *fw, void *context);
994 u32 opt_flags;
995};
996
997static void request_firmware_work_func(struct work_struct *work)
998{
999 struct firmware_work *fw_work;
1000 const struct firmware *fw;
1001
1002 fw_work = container_of(work, struct firmware_work, work);
1003
1004 _request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0,
1005 fw_work->opt_flags);
1006 fw_work->cont(fw, fw_work->context);
1007 put_device(fw_work->device); /* taken in request_firmware_nowait() */
1008
1009 module_put(fw_work->module);
1010 kfree_const(fw_work->name);
1011 kfree(fw_work);
1012}
1013
1014/**
1015 * request_firmware_nowait() - asynchronous version of request_firmware
1016 * @module: module requesting the firmware
1017 * @uevent: sends uevent to copy the firmware image if this flag
1018 * is non-zero else the firmware copy must be done manually.
1019 * @name: name of firmware file
1020 * @device: device for which firmware is being loaded
1021 * @gfp: allocation flags
1022 * @context: will be passed over to @cont, and
1023 * @fw may be %NULL if firmware request fails.
1024 * @cont: function will be called asynchronously when the firmware
1025 * request is over.
1026 *
1027 * Caller must hold the reference count of @device.
1028 *
1029 * Asynchronous variant of request_firmware() for user contexts:
1030 * - sleep for as small periods as possible since it may
1031 * increase kernel boot time of built-in device drivers
1032 * requesting firmware in their ->probe() methods, if
1033 * @gfp is GFP_KERNEL.
1034 *
1035 * - can't sleep at all if @gfp is GFP_ATOMIC.
1036 **/
1037int
1038request_firmware_nowait(
1039 struct module *module, bool uevent,
1040 const char *name, struct device *device, gfp_t gfp, void *context,
1041 void (*cont)(const struct firmware *fw, void *context))
1042{
1043 struct firmware_work *fw_work;
1044
1045 fw_work = kzalloc(sizeof(struct firmware_work), gfp);
1046 if (!fw_work)
1047 return -ENOMEM;
1048
1049 fw_work->module = module;
1050 fw_work->name = kstrdup_const(name, gfp);
1051 if (!fw_work->name) {
1052 kfree(fw_work);
1053 return -ENOMEM;
1054 }
1055 fw_work->device = device;
1056 fw_work->context = context;
1057 fw_work->cont = cont;
1058 fw_work->opt_flags = FW_OPT_NOWAIT |
1059 (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
1060
1061 if (!uevent && fw_cache_is_setup(device, name)) {
1062 kfree_const(fw_work->name);
1063 kfree(fw_work);
1064 return -EOPNOTSUPP;
1065 }
1066
1067 if (!try_module_get(module)) {
1068 kfree_const(fw_work->name);
1069 kfree(fw_work);
1070 return -EFAULT;
1071 }
1072
1073 get_device(fw_work->device);
1074 INIT_WORK(&fw_work->work, request_firmware_work_func);
1075 schedule_work(&fw_work->work);
1076 return 0;
1077}
1078EXPORT_SYMBOL(request_firmware_nowait);
1079
1080#ifdef CONFIG_FW_CACHE
1081static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1082
1083/**
1084 * cache_firmware() - cache one firmware image in kernel memory space
1085 * @fw_name: the firmware image name
1086 *
1087 * Cache firmware in kernel memory so that drivers can use it when
1088 * system isn't ready for them to request firmware image from userspace.
1089 * Once it returns successfully, driver can use request_firmware or its
1090 * nowait version to get the cached firmware without any interacting
1091 * with userspace
1092 *
1093 * Return 0 if the firmware image has been cached successfully
1094 * Return !0 otherwise
1095 *
1096 */
1097static int cache_firmware(const char *fw_name)
1098{
1099 int ret;
1100 const struct firmware *fw;
1101
1102 pr_debug("%s: %s\n", __func__, fw_name);
1103
1104 ret = request_firmware(&fw, fw_name, NULL);
1105 if (!ret)
1106 kfree(fw);
1107
1108 pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1109
1110 return ret;
1111}
1112
1113static struct fw_priv *lookup_fw_priv(const char *fw_name)
1114{
1115 struct fw_priv *tmp;
1116 struct firmware_cache *fwc = &fw_cache;
1117
1118 spin_lock(&fwc->lock);
1119 tmp = __lookup_fw_priv(fw_name);
1120 spin_unlock(&fwc->lock);
1121
1122 return tmp;
1123}
1124
1125/**
1126 * uncache_firmware() - remove one cached firmware image
1127 * @fw_name: the firmware image name
1128 *
1129 * Uncache one firmware image which has been cached successfully
1130 * before.
1131 *
1132 * Return 0 if the firmware cache has been removed successfully
1133 * Return !0 otherwise
1134 *
1135 */
1136static int uncache_firmware(const char *fw_name)
1137{
1138 struct fw_priv *fw_priv;
1139 struct firmware fw;
1140
1141 pr_debug("%s: %s\n", __func__, fw_name);
1142
1143 if (fw_get_builtin_firmware(&fw, fw_name, NULL, 0))
1144 return 0;
1145
1146 fw_priv = lookup_fw_priv(fw_name);
1147 if (fw_priv) {
1148 free_fw_priv(fw_priv);
1149 return 0;
1150 }
1151
1152 return -EINVAL;
1153}
1154
1155static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1156{
1157 struct fw_cache_entry *fce;
1158
1159 fce = kzalloc(sizeof(*fce), GFP_ATOMIC);
1160 if (!fce)
1161 goto exit;
1162
1163 fce->name = kstrdup_const(name, GFP_ATOMIC);
1164 if (!fce->name) {
1165 kfree(fce);
1166 fce = NULL;
1167 goto exit;
1168 }
1169exit:
1170 return fce;
1171}
1172
1173static int __fw_entry_found(const char *name)
1174{
1175 struct firmware_cache *fwc = &fw_cache;
1176 struct fw_cache_entry *fce;
1177
1178 list_for_each_entry(fce, &fwc->fw_names, list) {
1179 if (!strcmp(fce->name, name))
1180 return 1;
1181 }
1182 return 0;
1183}
1184
1185static int fw_cache_piggyback_on_request(const char *name)
1186{
1187 struct firmware_cache *fwc = &fw_cache;
1188 struct fw_cache_entry *fce;
1189 int ret = 0;
1190
1191 spin_lock(&fwc->name_lock);
1192 if (__fw_entry_found(name))
1193 goto found;
1194
1195 fce = alloc_fw_cache_entry(name);
1196 if (fce) {
1197 ret = 1;
1198 list_add(&fce->list, &fwc->fw_names);
1199 pr_debug("%s: fw: %s\n", __func__, name);
1200 }
1201found:
1202 spin_unlock(&fwc->name_lock);
1203 return ret;
1204}
1205
1206static void free_fw_cache_entry(struct fw_cache_entry *fce)
1207{
1208 kfree_const(fce->name);
1209 kfree(fce);
1210}
1211
1212static void __async_dev_cache_fw_image(void *fw_entry,
1213 async_cookie_t cookie)
1214{
1215 struct fw_cache_entry *fce = fw_entry;
1216 struct firmware_cache *fwc = &fw_cache;
1217 int ret;
1218
1219 ret = cache_firmware(fce->name);
1220 if (ret) {
1221 spin_lock(&fwc->name_lock);
1222 list_del(&fce->list);
1223 spin_unlock(&fwc->name_lock);
1224
1225 free_fw_cache_entry(fce);
1226 }
1227}
1228
1229/* called with dev->devres_lock held */
1230static void dev_create_fw_entry(struct device *dev, void *res,
1231 void *data)
1232{
1233 struct fw_name_devm *fwn = res;
1234 const char *fw_name = fwn->name;
1235 struct list_head *head = data;
1236 struct fw_cache_entry *fce;
1237
1238 fce = alloc_fw_cache_entry(fw_name);
1239 if (fce)
1240 list_add(&fce->list, head);
1241}
1242
1243static int devm_name_match(struct device *dev, void *res,
1244 void *match_data)
1245{
1246 struct fw_name_devm *fwn = res;
1247 return (fwn->magic == (unsigned long)match_data);
1248}
1249
1250static void dev_cache_fw_image(struct device *dev, void *data)
1251{
1252 LIST_HEAD(todo);
1253 struct fw_cache_entry *fce;
1254 struct fw_cache_entry *fce_next;
1255 struct firmware_cache *fwc = &fw_cache;
1256
1257 devres_for_each_res(dev, fw_name_devm_release,
1258 devm_name_match, &fw_cache,
1259 dev_create_fw_entry, &todo);
1260
1261 list_for_each_entry_safe(fce, fce_next, &todo, list) {
1262 list_del(&fce->list);
1263
1264 spin_lock(&fwc->name_lock);
1265 /* only one cache entry for one firmware */
1266 if (!__fw_entry_found(fce->name)) {
1267 list_add(&fce->list, &fwc->fw_names);
1268 } else {
1269 free_fw_cache_entry(fce);
1270 fce = NULL;
1271 }
1272 spin_unlock(&fwc->name_lock);
1273
1274 if (fce)
1275 async_schedule_domain(__async_dev_cache_fw_image,
1276 (void *)fce,
1277 &fw_cache_domain);
1278 }
1279}
1280
1281static void __device_uncache_fw_images(void)
1282{
1283 struct firmware_cache *fwc = &fw_cache;
1284 struct fw_cache_entry *fce;
1285
1286 spin_lock(&fwc->name_lock);
1287 while (!list_empty(&fwc->fw_names)) {
1288 fce = list_entry(fwc->fw_names.next,
1289 struct fw_cache_entry, list);
1290 list_del(&fce->list);
1291 spin_unlock(&fwc->name_lock);
1292
1293 uncache_firmware(fce->name);
1294 free_fw_cache_entry(fce);
1295
1296 spin_lock(&fwc->name_lock);
1297 }
1298 spin_unlock(&fwc->name_lock);
1299}
1300
1301/**
1302 * device_cache_fw_images() - cache devices' firmware
1303 *
1304 * If one device called request_firmware or its nowait version
1305 * successfully before, the firmware names are recored into the
1306 * device's devres link list, so device_cache_fw_images can call
1307 * cache_firmware() to cache these firmwares for the device,
1308 * then the device driver can load its firmwares easily at
1309 * time when system is not ready to complete loading firmware.
1310 */
1311static void device_cache_fw_images(void)
1312{
1313 struct firmware_cache *fwc = &fw_cache;
1314 DEFINE_WAIT(wait);
1315
1316 pr_debug("%s\n", __func__);
1317
1318 /* cancel uncache work */
1319 cancel_delayed_work_sync(&fwc->work);
1320
1321 fw_fallback_set_cache_timeout();
1322
1323 mutex_lock(&fw_lock);
1324 fwc->state = FW_LOADER_START_CACHE;
1325 dpm_for_each_dev(NULL, dev_cache_fw_image);
1326 mutex_unlock(&fw_lock);
1327
1328 /* wait for completion of caching firmware for all devices */
1329 async_synchronize_full_domain(&fw_cache_domain);
1330
1331 fw_fallback_set_default_timeout();
1332}
1333
1334/**
1335 * device_uncache_fw_images() - uncache devices' firmware
1336 *
1337 * uncache all firmwares which have been cached successfully
1338 * by device_uncache_fw_images earlier
1339 */
1340static void device_uncache_fw_images(void)
1341{
1342 pr_debug("%s\n", __func__);
1343 __device_uncache_fw_images();
1344}
1345
1346static void device_uncache_fw_images_work(struct work_struct *work)
1347{
1348 device_uncache_fw_images();
1349}
1350
1351/**
1352 * device_uncache_fw_images_delay() - uncache devices firmwares
1353 * @delay: number of milliseconds to delay uncache device firmwares
1354 *
1355 * uncache all devices's firmwares which has been cached successfully
1356 * by device_cache_fw_images after @delay milliseconds.
1357 */
1358static void device_uncache_fw_images_delay(unsigned long delay)
1359{
1360 queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1361 msecs_to_jiffies(delay));
1362}
1363
1364static int fw_pm_notify(struct notifier_block *notify_block,
1365 unsigned long mode, void *unused)
1366{
1367 switch (mode) {
1368 case PM_HIBERNATION_PREPARE:
1369 case PM_SUSPEND_PREPARE:
1370 case PM_RESTORE_PREPARE:
1371 /*
1372 * kill pending fallback requests with a custom fallback
1373 * to avoid stalling suspend.
1374 */
1375 kill_pending_fw_fallback_reqs(true);
1376 device_cache_fw_images();
1377 break;
1378
1379 case PM_POST_SUSPEND:
1380 case PM_POST_HIBERNATION:
1381 case PM_POST_RESTORE:
1382 /*
1383 * In case that system sleep failed and syscore_suspend is
1384 * not called.
1385 */
1386 mutex_lock(&fw_lock);
1387 fw_cache.state = FW_LOADER_NO_CACHE;
1388 mutex_unlock(&fw_lock);
1389
1390 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1391 break;
1392 }
1393
1394 return 0;
1395}
1396
1397/* stop caching firmware once syscore_suspend is reached */
1398static int fw_suspend(void)
1399{
1400 fw_cache.state = FW_LOADER_NO_CACHE;
1401 return 0;
1402}
1403
1404static struct syscore_ops fw_syscore_ops = {
1405 .suspend = fw_suspend,
1406};
1407
1408static int __init register_fw_pm_ops(void)
1409{
1410 int ret;
1411
1412 spin_lock_init(&fw_cache.name_lock);
1413 INIT_LIST_HEAD(&fw_cache.fw_names);
1414
1415 INIT_DELAYED_WORK(&fw_cache.work,
1416 device_uncache_fw_images_work);
1417
1418 fw_cache.pm_notify.notifier_call = fw_pm_notify;
1419 ret = register_pm_notifier(&fw_cache.pm_notify);
1420 if (ret)
1421 return ret;
1422
1423 register_syscore_ops(&fw_syscore_ops);
1424
1425 return ret;
1426}
1427
1428static inline void unregister_fw_pm_ops(void)
1429{
1430 unregister_syscore_ops(&fw_syscore_ops);
1431 unregister_pm_notifier(&fw_cache.pm_notify);
1432}
1433#else
1434static int fw_cache_piggyback_on_request(const char *name)
1435{
1436 return 0;
1437}
1438static inline int register_fw_pm_ops(void)
1439{
1440 return 0;
1441}
1442static inline void unregister_fw_pm_ops(void)
1443{
1444}
1445#endif
1446
1447static void __init fw_cache_init(void)
1448{
1449 spin_lock_init(&fw_cache.lock);
1450 INIT_LIST_HEAD(&fw_cache.head);
1451 fw_cache.state = FW_LOADER_NO_CACHE;
1452}
1453
1454static int fw_shutdown_notify(struct notifier_block *unused1,
1455 unsigned long unused2, void *unused3)
1456{
1457 /*
1458 * Kill all pending fallback requests to avoid both stalling shutdown,
1459 * and avoid a deadlock with the usermode_lock.
1460 */
1461 kill_pending_fw_fallback_reqs(false);
1462
1463 return NOTIFY_DONE;
1464}
1465
1466static struct notifier_block fw_shutdown_nb = {
1467 .notifier_call = fw_shutdown_notify,
1468};
1469
1470static int __init firmware_class_init(void)
1471{
1472 int ret;
1473
1474 /* No need to unfold these on exit */
1475 fw_cache_init();
1476
1477 ret = register_fw_pm_ops();
1478 if (ret)
1479 return ret;
1480
1481 ret = register_reboot_notifier(&fw_shutdown_nb);
1482 if (ret)
1483 goto out;
1484
1485 return register_sysfs_loader();
1486
1487out:
1488 unregister_fw_pm_ops();
1489 return ret;
1490}
1491
1492static void __exit firmware_class_exit(void)
1493{
1494 unregister_fw_pm_ops();
1495 unregister_reboot_notifier(&fw_shutdown_nb);
1496 unregister_sysfs_loader();
1497}
1498
1499fs_initcall(firmware_class_init);
1500module_exit(firmware_class_exit);
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * main.c - Multi purpose firmware loading support
4 *
5 * Copyright (c) 2003 Manuel Estrada Sainz
6 *
7 * Please see Documentation/firmware_class/ for more information.
8 *
9 */
10
11#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12
13#include <linux/capability.h>
14#include <linux/device.h>
15#include <linux/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>
29#include <linux/fs.h>
30#include <linux/async.h>
31#include <linux/pm.h>
32#include <linux/suspend.h>
33#include <linux/syscore_ops.h>
34#include <linux/reboot.h>
35#include <linux/security.h>
36
37#include <generated/utsrelease.h>
38
39#include "../base.h"
40#include "firmware.h"
41#include "fallback.h"
42
43MODULE_AUTHOR("Manuel Estrada Sainz");
44MODULE_DESCRIPTION("Multi purpose firmware loading support");
45MODULE_LICENSE("GPL");
46
47struct firmware_cache {
48 /* firmware_buf instance will be added into the below list */
49 spinlock_t lock;
50 struct list_head head;
51 int state;
52
53#ifdef CONFIG_PM_SLEEP
54 /*
55 * Names of firmware images which have been cached successfully
56 * will be added into the below list so that device uncache
57 * helper can trace which firmware images have been cached
58 * before.
59 */
60 spinlock_t name_lock;
61 struct list_head fw_names;
62
63 struct delayed_work work;
64
65 struct notifier_block pm_notify;
66#endif
67};
68
69struct fw_cache_entry {
70 struct list_head list;
71 const char *name;
72};
73
74struct fw_name_devm {
75 unsigned long magic;
76 const char *name;
77};
78
79static inline struct fw_priv *to_fw_priv(struct kref *ref)
80{
81 return container_of(ref, struct fw_priv, ref);
82}
83
84#define FW_LOADER_NO_CACHE 0
85#define FW_LOADER_START_CACHE 1
86
87/* fw_lock could be moved to 'struct fw_sysfs' but since it is just
88 * guarding for corner cases a global lock should be OK */
89DEFINE_MUTEX(fw_lock);
90
91static struct firmware_cache fw_cache;
92
93/* Builtin firmware support */
94
95#ifdef CONFIG_FW_LOADER
96
97extern struct builtin_fw __start_builtin_fw[];
98extern struct builtin_fw __end_builtin_fw[];
99
100static void fw_copy_to_prealloc_buf(struct firmware *fw,
101 void *buf, size_t size)
102{
103 if (!buf || size < fw->size)
104 return;
105 memcpy(buf, fw->data, fw->size);
106}
107
108static bool fw_get_builtin_firmware(struct firmware *fw, const char *name,
109 void *buf, size_t size)
110{
111 struct builtin_fw *b_fw;
112
113 for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
114 if (strcmp(name, b_fw->name) == 0) {
115 fw->size = b_fw->size;
116 fw->data = b_fw->data;
117 fw_copy_to_prealloc_buf(fw, buf, size);
118
119 return true;
120 }
121 }
122
123 return false;
124}
125
126static bool fw_is_builtin_firmware(const struct firmware *fw)
127{
128 struct builtin_fw *b_fw;
129
130 for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
131 if (fw->data == b_fw->data)
132 return true;
133
134 return false;
135}
136
137#else /* Module case - no builtin firmware support */
138
139static inline bool fw_get_builtin_firmware(struct firmware *fw,
140 const char *name, void *buf,
141 size_t size)
142{
143 return false;
144}
145
146static inline bool fw_is_builtin_firmware(const struct firmware *fw)
147{
148 return false;
149}
150#endif
151
152static void fw_state_init(struct fw_priv *fw_priv)
153{
154 struct fw_state *fw_st = &fw_priv->fw_st;
155
156 init_completion(&fw_st->completion);
157 fw_st->status = FW_STATUS_UNKNOWN;
158}
159
160static inline int fw_state_wait(struct fw_priv *fw_priv)
161{
162 return __fw_state_wait_common(fw_priv, MAX_SCHEDULE_TIMEOUT);
163}
164
165static int fw_cache_piggyback_on_request(const char *name);
166
167static struct fw_priv *__allocate_fw_priv(const char *fw_name,
168 struct firmware_cache *fwc,
169 void *dbuf, size_t size)
170{
171 struct fw_priv *fw_priv;
172
173 fw_priv = kzalloc(sizeof(*fw_priv), GFP_ATOMIC);
174 if (!fw_priv)
175 return NULL;
176
177 fw_priv->fw_name = kstrdup_const(fw_name, GFP_ATOMIC);
178 if (!fw_priv->fw_name) {
179 kfree(fw_priv);
180 return NULL;
181 }
182
183 kref_init(&fw_priv->ref);
184 fw_priv->fwc = fwc;
185 fw_priv->data = dbuf;
186 fw_priv->allocated_size = size;
187 fw_state_init(fw_priv);
188#ifdef CONFIG_FW_LOADER_USER_HELPER
189 INIT_LIST_HEAD(&fw_priv->pending_list);
190#endif
191
192 pr_debug("%s: fw-%s fw_priv=%p\n", __func__, fw_name, fw_priv);
193
194 return fw_priv;
195}
196
197static struct fw_priv *__lookup_fw_priv(const char *fw_name)
198{
199 struct fw_priv *tmp;
200 struct firmware_cache *fwc = &fw_cache;
201
202 list_for_each_entry(tmp, &fwc->head, list)
203 if (!strcmp(tmp->fw_name, fw_name))
204 return tmp;
205 return NULL;
206}
207
208/* Returns 1 for batching firmware requests with the same name */
209static int alloc_lookup_fw_priv(const char *fw_name,
210 struct firmware_cache *fwc,
211 struct fw_priv **fw_priv, void *dbuf,
212 size_t size)
213{
214 struct fw_priv *tmp;
215
216 spin_lock(&fwc->lock);
217 tmp = __lookup_fw_priv(fw_name);
218 if (tmp) {
219 kref_get(&tmp->ref);
220 spin_unlock(&fwc->lock);
221 *fw_priv = tmp;
222 pr_debug("batched request - sharing the same struct fw_priv and lookup for multiple requests\n");
223 return 1;
224 }
225 tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size);
226 if (tmp)
227 list_add(&tmp->list, &fwc->head);
228 spin_unlock(&fwc->lock);
229
230 *fw_priv = tmp;
231
232 return tmp ? 0 : -ENOMEM;
233}
234
235static void __free_fw_priv(struct kref *ref)
236 __releases(&fwc->lock)
237{
238 struct fw_priv *fw_priv = to_fw_priv(ref);
239 struct firmware_cache *fwc = fw_priv->fwc;
240
241 pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
242 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
243 (unsigned int)fw_priv->size);
244
245 list_del(&fw_priv->list);
246 spin_unlock(&fwc->lock);
247
248#ifdef CONFIG_FW_LOADER_USER_HELPER
249 if (fw_priv->is_paged_buf) {
250 int i;
251 vunmap(fw_priv->data);
252 for (i = 0; i < fw_priv->nr_pages; i++)
253 __free_page(fw_priv->pages[i]);
254 vfree(fw_priv->pages);
255 } else
256#endif
257 if (!fw_priv->allocated_size)
258 vfree(fw_priv->data);
259 kfree_const(fw_priv->fw_name);
260 kfree(fw_priv);
261}
262
263static void free_fw_priv(struct fw_priv *fw_priv)
264{
265 struct firmware_cache *fwc = fw_priv->fwc;
266 spin_lock(&fwc->lock);
267 if (!kref_put(&fw_priv->ref, __free_fw_priv))
268 spin_unlock(&fwc->lock);
269}
270
271/* direct firmware loading support */
272static char fw_path_para[256];
273static const char * const fw_path[] = {
274 fw_path_para,
275 "/lib/firmware/updates/" UTS_RELEASE,
276 "/lib/firmware/updates",
277 "/lib/firmware/" UTS_RELEASE,
278 "/lib/firmware"
279};
280
281/*
282 * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
283 * from kernel command line because firmware_class is generally built in
284 * kernel instead of module.
285 */
286module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
287MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
288
289static int
290fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv)
291{
292 loff_t size;
293 int i, len;
294 int rc = -ENOENT;
295 char *path;
296 enum kernel_read_file_id id = READING_FIRMWARE;
297 size_t msize = INT_MAX;
298
299 /* Already populated data member means we're loading into a buffer */
300 if (fw_priv->data) {
301 id = READING_FIRMWARE_PREALLOC_BUFFER;
302 msize = fw_priv->allocated_size;
303 }
304
305 path = __getname();
306 if (!path)
307 return -ENOMEM;
308
309 for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
310 /* skip the unset customized path */
311 if (!fw_path[i][0])
312 continue;
313
314 len = snprintf(path, PATH_MAX, "%s/%s",
315 fw_path[i], fw_priv->fw_name);
316 if (len >= PATH_MAX) {
317 rc = -ENAMETOOLONG;
318 break;
319 }
320
321 fw_priv->size = 0;
322 rc = kernel_read_file_from_path(path, &fw_priv->data, &size,
323 msize, id);
324 if (rc) {
325 if (rc == -ENOENT)
326 dev_dbg(device, "loading %s failed with error %d\n",
327 path, rc);
328 else
329 dev_warn(device, "loading %s failed with error %d\n",
330 path, rc);
331 continue;
332 }
333 dev_dbg(device, "direct-loading %s\n", fw_priv->fw_name);
334 fw_priv->size = size;
335 fw_state_done(fw_priv);
336 break;
337 }
338 __putname(path);
339
340 return rc;
341}
342
343/* firmware holds the ownership of pages */
344static void firmware_free_data(const struct firmware *fw)
345{
346 /* Loaded directly? */
347 if (!fw->priv) {
348 vfree(fw->data);
349 return;
350 }
351 free_fw_priv(fw->priv);
352}
353
354/* store the pages buffer info firmware from buf */
355static void fw_set_page_data(struct fw_priv *fw_priv, struct firmware *fw)
356{
357 fw->priv = fw_priv;
358#ifdef CONFIG_FW_LOADER_USER_HELPER
359 fw->pages = fw_priv->pages;
360#endif
361 fw->size = fw_priv->size;
362 fw->data = fw_priv->data;
363
364 pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
365 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
366 (unsigned int)fw_priv->size);
367}
368
369#ifdef CONFIG_PM_SLEEP
370static void fw_name_devm_release(struct device *dev, void *res)
371{
372 struct fw_name_devm *fwn = res;
373
374 if (fwn->magic == (unsigned long)&fw_cache)
375 pr_debug("%s: fw_name-%s devm-%p released\n",
376 __func__, fwn->name, res);
377 kfree_const(fwn->name);
378}
379
380static int fw_devm_match(struct device *dev, void *res,
381 void *match_data)
382{
383 struct fw_name_devm *fwn = res;
384
385 return (fwn->magic == (unsigned long)&fw_cache) &&
386 !strcmp(fwn->name, match_data);
387}
388
389static struct fw_name_devm *fw_find_devm_name(struct device *dev,
390 const char *name)
391{
392 struct fw_name_devm *fwn;
393
394 fwn = devres_find(dev, fw_name_devm_release,
395 fw_devm_match, (void *)name);
396 return fwn;
397}
398
399static bool fw_cache_is_setup(struct device *dev, const char *name)
400{
401 struct fw_name_devm *fwn;
402
403 fwn = fw_find_devm_name(dev, name);
404 if (fwn)
405 return true;
406
407 return false;
408}
409
410/* add firmware name into devres list */
411static int fw_add_devm_name(struct device *dev, const char *name)
412{
413 struct fw_name_devm *fwn;
414
415 if (fw_cache_is_setup(dev, name))
416 return 0;
417
418 fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm),
419 GFP_KERNEL);
420 if (!fwn)
421 return -ENOMEM;
422 fwn->name = kstrdup_const(name, GFP_KERNEL);
423 if (!fwn->name) {
424 devres_free(fwn);
425 return -ENOMEM;
426 }
427
428 fwn->magic = (unsigned long)&fw_cache;
429 devres_add(dev, fwn);
430
431 return 0;
432}
433#else
434static bool fw_cache_is_setup(struct device *dev, const char *name)
435{
436 return false;
437}
438
439static int fw_add_devm_name(struct device *dev, const char *name)
440{
441 return 0;
442}
443#endif
444
445int assign_fw(struct firmware *fw, struct device *device,
446 unsigned int opt_flags)
447{
448 struct fw_priv *fw_priv = fw->priv;
449 int ret;
450
451 mutex_lock(&fw_lock);
452 if (!fw_priv->size || fw_state_is_aborted(fw_priv)) {
453 mutex_unlock(&fw_lock);
454 return -ENOENT;
455 }
456
457 /*
458 * add firmware name into devres list so that we can auto cache
459 * and uncache firmware for device.
460 *
461 * device may has been deleted already, but the problem
462 * should be fixed in devres or driver core.
463 */
464 /* don't cache firmware handled without uevent */
465 if (device && (opt_flags & FW_OPT_UEVENT) &&
466 !(opt_flags & FW_OPT_NOCACHE)) {
467 ret = fw_add_devm_name(device, fw_priv->fw_name);
468 if (ret) {
469 mutex_unlock(&fw_lock);
470 return ret;
471 }
472 }
473
474 /*
475 * After caching firmware image is started, let it piggyback
476 * on request firmware.
477 */
478 if (!(opt_flags & FW_OPT_NOCACHE) &&
479 fw_priv->fwc->state == FW_LOADER_START_CACHE) {
480 if (fw_cache_piggyback_on_request(fw_priv->fw_name))
481 kref_get(&fw_priv->ref);
482 }
483
484 /* pass the pages buffer to driver at the last minute */
485 fw_set_page_data(fw_priv, fw);
486 mutex_unlock(&fw_lock);
487 return 0;
488}
489
490/* prepare firmware and firmware_buf structs;
491 * return 0 if a firmware is already assigned, 1 if need to load one,
492 * or a negative error code
493 */
494static int
495_request_firmware_prepare(struct firmware **firmware_p, const char *name,
496 struct device *device, void *dbuf, size_t size)
497{
498 struct firmware *firmware;
499 struct fw_priv *fw_priv;
500 int ret;
501
502 *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
503 if (!firmware) {
504 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
505 __func__);
506 return -ENOMEM;
507 }
508
509 if (fw_get_builtin_firmware(firmware, name, dbuf, size)) {
510 dev_dbg(device, "using built-in %s\n", name);
511 return 0; /* assigned */
512 }
513
514 ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv, dbuf, size);
515
516 /*
517 * bind with 'priv' now to avoid warning in failure path
518 * of requesting firmware.
519 */
520 firmware->priv = fw_priv;
521
522 if (ret > 0) {
523 ret = fw_state_wait(fw_priv);
524 if (!ret) {
525 fw_set_page_data(fw_priv, firmware);
526 return 0; /* assigned */
527 }
528 }
529
530 if (ret < 0)
531 return ret;
532 return 1; /* need to load */
533}
534
535/*
536 * Batched requests need only one wake, we need to do this step last due to the
537 * fallback mechanism. The buf is protected with kref_get(), and it won't be
538 * released until the last user calls release_firmware().
539 *
540 * Failed batched requests are possible as well, in such cases we just share
541 * the struct fw_priv and won't release it until all requests are woken
542 * and have gone through this same path.
543 */
544static void fw_abort_batch_reqs(struct firmware *fw)
545{
546 struct fw_priv *fw_priv;
547
548 /* Loaded directly? */
549 if (!fw || !fw->priv)
550 return;
551
552 fw_priv = fw->priv;
553 if (!fw_state_is_aborted(fw_priv))
554 fw_state_aborted(fw_priv);
555}
556
557/* called from request_firmware() and request_firmware_work_func() */
558static int
559_request_firmware(const struct firmware **firmware_p, const char *name,
560 struct device *device, void *buf, size_t size,
561 unsigned int opt_flags)
562{
563 struct firmware *fw = NULL;
564 int ret;
565
566 if (!firmware_p)
567 return -EINVAL;
568
569 if (!name || name[0] == '\0') {
570 ret = -EINVAL;
571 goto out;
572 }
573
574 ret = _request_firmware_prepare(&fw, name, device, buf, size);
575 if (ret <= 0) /* error or already assigned */
576 goto out;
577
578 ret = fw_get_filesystem_firmware(device, fw->priv);
579 if (ret) {
580 if (!(opt_flags & FW_OPT_NO_WARN))
581 dev_warn(device,
582 "Direct firmware load for %s failed with error %d\n",
583 name, ret);
584 ret = fw_sysfs_fallback(fw, name, device, opt_flags, ret);
585 } else
586 ret = assign_fw(fw, device, opt_flags);
587
588 out:
589 if (ret < 0) {
590 fw_abort_batch_reqs(fw);
591 release_firmware(fw);
592 fw = NULL;
593 }
594
595 *firmware_p = fw;
596 return ret;
597}
598
599/**
600 * request_firmware: - send firmware request and wait for it
601 * @firmware_p: pointer to firmware image
602 * @name: name of firmware file
603 * @device: device for which firmware is being loaded
604 *
605 * @firmware_p will be used to return a firmware image by the name
606 * of @name for device @device.
607 *
608 * Should be called from user context where sleeping is allowed.
609 *
610 * @name will be used as $FIRMWARE in the uevent environment and
611 * should be distinctive enough not to be confused with any other
612 * firmware image for this or any other device.
613 *
614 * Caller must hold the reference count of @device.
615 *
616 * The function can be called safely inside device's suspend and
617 * resume callback.
618 **/
619int
620request_firmware(const struct firmware **firmware_p, const char *name,
621 struct device *device)
622{
623 int ret;
624
625 /* Need to pin this module until return */
626 __module_get(THIS_MODULE);
627 ret = _request_firmware(firmware_p, name, device, NULL, 0,
628 FW_OPT_UEVENT);
629 module_put(THIS_MODULE);
630 return ret;
631}
632EXPORT_SYMBOL(request_firmware);
633
634/**
635 * request_firmware_direct: - load firmware directly without usermode helper
636 * @firmware_p: pointer to firmware image
637 * @name: name of firmware file
638 * @device: device for which firmware is being loaded
639 *
640 * This function works pretty much like request_firmware(), but this doesn't
641 * fall back to usermode helper even if the firmware couldn't be loaded
642 * directly from fs. Hence it's useful for loading optional firmwares, which
643 * aren't always present, without extra long timeouts of udev.
644 **/
645int request_firmware_direct(const struct firmware **firmware_p,
646 const char *name, struct device *device)
647{
648 int ret;
649
650 __module_get(THIS_MODULE);
651 ret = _request_firmware(firmware_p, name, device, NULL, 0,
652 FW_OPT_UEVENT | FW_OPT_NO_WARN |
653 FW_OPT_NOFALLBACK);
654 module_put(THIS_MODULE);
655 return ret;
656}
657EXPORT_SYMBOL_GPL(request_firmware_direct);
658
659/**
660 * firmware_request_cache: - cache firmware for suspend so resume can use it
661 * @name: name of firmware file
662 * @device: device for which firmware should be cached for
663 *
664 * There are some devices with an optimization that enables the device to not
665 * require loading firmware on system reboot. This optimization may still
666 * require the firmware present on resume from suspend. This routine can be
667 * used to ensure the firmware is present on resume from suspend in these
668 * situations. This helper is not compatible with drivers which use
669 * request_firmware_into_buf() or request_firmware_nowait() with no uevent set.
670 **/
671int firmware_request_cache(struct device *device, const char *name)
672{
673 int ret;
674
675 mutex_lock(&fw_lock);
676 ret = fw_add_devm_name(device, name);
677 mutex_unlock(&fw_lock);
678
679 return ret;
680}
681EXPORT_SYMBOL_GPL(firmware_request_cache);
682
683/**
684 * request_firmware_into_buf - load firmware into a previously allocated buffer
685 * @firmware_p: pointer to firmware image
686 * @name: name of firmware file
687 * @device: device for which firmware is being loaded and DMA region allocated
688 * @buf: address of buffer to load firmware into
689 * @size: size of buffer
690 *
691 * This function works pretty much like request_firmware(), but it doesn't
692 * allocate a buffer to hold the firmware data. Instead, the firmware
693 * is loaded directly into the buffer pointed to by @buf and the @firmware_p
694 * data member is pointed at @buf.
695 *
696 * This function doesn't cache firmware either.
697 */
698int
699request_firmware_into_buf(const struct firmware **firmware_p, const char *name,
700 struct device *device, void *buf, size_t size)
701{
702 int ret;
703
704 if (fw_cache_is_setup(device, name))
705 return -EOPNOTSUPP;
706
707 __module_get(THIS_MODULE);
708 ret = _request_firmware(firmware_p, name, device, buf, size,
709 FW_OPT_UEVENT | FW_OPT_NOCACHE);
710 module_put(THIS_MODULE);
711 return ret;
712}
713EXPORT_SYMBOL(request_firmware_into_buf);
714
715/**
716 * release_firmware: - release the resource associated with a firmware image
717 * @fw: firmware resource to release
718 **/
719void release_firmware(const struct firmware *fw)
720{
721 if (fw) {
722 if (!fw_is_builtin_firmware(fw))
723 firmware_free_data(fw);
724 kfree(fw);
725 }
726}
727EXPORT_SYMBOL(release_firmware);
728
729/* Async support */
730struct firmware_work {
731 struct work_struct work;
732 struct module *module;
733 const char *name;
734 struct device *device;
735 void *context;
736 void (*cont)(const struct firmware *fw, void *context);
737 unsigned int opt_flags;
738};
739
740static void request_firmware_work_func(struct work_struct *work)
741{
742 struct firmware_work *fw_work;
743 const struct firmware *fw;
744
745 fw_work = container_of(work, struct firmware_work, work);
746
747 _request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0,
748 fw_work->opt_flags);
749 fw_work->cont(fw, fw_work->context);
750 put_device(fw_work->device); /* taken in request_firmware_nowait() */
751
752 module_put(fw_work->module);
753 kfree_const(fw_work->name);
754 kfree(fw_work);
755}
756
757/**
758 * request_firmware_nowait - asynchronous version of request_firmware
759 * @module: module requesting the firmware
760 * @uevent: sends uevent to copy the firmware image if this flag
761 * is non-zero else the firmware copy must be done manually.
762 * @name: name of firmware file
763 * @device: device for which firmware is being loaded
764 * @gfp: allocation flags
765 * @context: will be passed over to @cont, and
766 * @fw may be %NULL if firmware request fails.
767 * @cont: function will be called asynchronously when the firmware
768 * request is over.
769 *
770 * Caller must hold the reference count of @device.
771 *
772 * Asynchronous variant of request_firmware() for user contexts:
773 * - sleep for as small periods as possible since it may
774 * increase kernel boot time of built-in device drivers
775 * requesting firmware in their ->probe() methods, if
776 * @gfp is GFP_KERNEL.
777 *
778 * - can't sleep at all if @gfp is GFP_ATOMIC.
779 **/
780int
781request_firmware_nowait(
782 struct module *module, bool uevent,
783 const char *name, struct device *device, gfp_t gfp, void *context,
784 void (*cont)(const struct firmware *fw, void *context))
785{
786 struct firmware_work *fw_work;
787
788 fw_work = kzalloc(sizeof(struct firmware_work), gfp);
789 if (!fw_work)
790 return -ENOMEM;
791
792 fw_work->module = module;
793 fw_work->name = kstrdup_const(name, gfp);
794 if (!fw_work->name) {
795 kfree(fw_work);
796 return -ENOMEM;
797 }
798 fw_work->device = device;
799 fw_work->context = context;
800 fw_work->cont = cont;
801 fw_work->opt_flags = FW_OPT_NOWAIT |
802 (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
803
804 if (!uevent && fw_cache_is_setup(device, name)) {
805 kfree_const(fw_work->name);
806 kfree(fw_work);
807 return -EOPNOTSUPP;
808 }
809
810 if (!try_module_get(module)) {
811 kfree_const(fw_work->name);
812 kfree(fw_work);
813 return -EFAULT;
814 }
815
816 get_device(fw_work->device);
817 INIT_WORK(&fw_work->work, request_firmware_work_func);
818 schedule_work(&fw_work->work);
819 return 0;
820}
821EXPORT_SYMBOL(request_firmware_nowait);
822
823#ifdef CONFIG_PM_SLEEP
824static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
825
826/**
827 * cache_firmware - cache one firmware image in kernel memory space
828 * @fw_name: the firmware image name
829 *
830 * Cache firmware in kernel memory so that drivers can use it when
831 * system isn't ready for them to request firmware image from userspace.
832 * Once it returns successfully, driver can use request_firmware or its
833 * nowait version to get the cached firmware without any interacting
834 * with userspace
835 *
836 * Return 0 if the firmware image has been cached successfully
837 * Return !0 otherwise
838 *
839 */
840static int cache_firmware(const char *fw_name)
841{
842 int ret;
843 const struct firmware *fw;
844
845 pr_debug("%s: %s\n", __func__, fw_name);
846
847 ret = request_firmware(&fw, fw_name, NULL);
848 if (!ret)
849 kfree(fw);
850
851 pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
852
853 return ret;
854}
855
856static struct fw_priv *lookup_fw_priv(const char *fw_name)
857{
858 struct fw_priv *tmp;
859 struct firmware_cache *fwc = &fw_cache;
860
861 spin_lock(&fwc->lock);
862 tmp = __lookup_fw_priv(fw_name);
863 spin_unlock(&fwc->lock);
864
865 return tmp;
866}
867
868/**
869 * uncache_firmware - remove one cached firmware image
870 * @fw_name: the firmware image name
871 *
872 * Uncache one firmware image which has been cached successfully
873 * before.
874 *
875 * Return 0 if the firmware cache has been removed successfully
876 * Return !0 otherwise
877 *
878 */
879static int uncache_firmware(const char *fw_name)
880{
881 struct fw_priv *fw_priv;
882 struct firmware fw;
883
884 pr_debug("%s: %s\n", __func__, fw_name);
885
886 if (fw_get_builtin_firmware(&fw, fw_name, NULL, 0))
887 return 0;
888
889 fw_priv = lookup_fw_priv(fw_name);
890 if (fw_priv) {
891 free_fw_priv(fw_priv);
892 return 0;
893 }
894
895 return -EINVAL;
896}
897
898static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
899{
900 struct fw_cache_entry *fce;
901
902 fce = kzalloc(sizeof(*fce), GFP_ATOMIC);
903 if (!fce)
904 goto exit;
905
906 fce->name = kstrdup_const(name, GFP_ATOMIC);
907 if (!fce->name) {
908 kfree(fce);
909 fce = NULL;
910 goto exit;
911 }
912exit:
913 return fce;
914}
915
916static int __fw_entry_found(const char *name)
917{
918 struct firmware_cache *fwc = &fw_cache;
919 struct fw_cache_entry *fce;
920
921 list_for_each_entry(fce, &fwc->fw_names, list) {
922 if (!strcmp(fce->name, name))
923 return 1;
924 }
925 return 0;
926}
927
928static int fw_cache_piggyback_on_request(const char *name)
929{
930 struct firmware_cache *fwc = &fw_cache;
931 struct fw_cache_entry *fce;
932 int ret = 0;
933
934 spin_lock(&fwc->name_lock);
935 if (__fw_entry_found(name))
936 goto found;
937
938 fce = alloc_fw_cache_entry(name);
939 if (fce) {
940 ret = 1;
941 list_add(&fce->list, &fwc->fw_names);
942 pr_debug("%s: fw: %s\n", __func__, name);
943 }
944found:
945 spin_unlock(&fwc->name_lock);
946 return ret;
947}
948
949static void free_fw_cache_entry(struct fw_cache_entry *fce)
950{
951 kfree_const(fce->name);
952 kfree(fce);
953}
954
955static void __async_dev_cache_fw_image(void *fw_entry,
956 async_cookie_t cookie)
957{
958 struct fw_cache_entry *fce = fw_entry;
959 struct firmware_cache *fwc = &fw_cache;
960 int ret;
961
962 ret = cache_firmware(fce->name);
963 if (ret) {
964 spin_lock(&fwc->name_lock);
965 list_del(&fce->list);
966 spin_unlock(&fwc->name_lock);
967
968 free_fw_cache_entry(fce);
969 }
970}
971
972/* called with dev->devres_lock held */
973static void dev_create_fw_entry(struct device *dev, void *res,
974 void *data)
975{
976 struct fw_name_devm *fwn = res;
977 const char *fw_name = fwn->name;
978 struct list_head *head = data;
979 struct fw_cache_entry *fce;
980
981 fce = alloc_fw_cache_entry(fw_name);
982 if (fce)
983 list_add(&fce->list, head);
984}
985
986static int devm_name_match(struct device *dev, void *res,
987 void *match_data)
988{
989 struct fw_name_devm *fwn = res;
990 return (fwn->magic == (unsigned long)match_data);
991}
992
993static void dev_cache_fw_image(struct device *dev, void *data)
994{
995 LIST_HEAD(todo);
996 struct fw_cache_entry *fce;
997 struct fw_cache_entry *fce_next;
998 struct firmware_cache *fwc = &fw_cache;
999
1000 devres_for_each_res(dev, fw_name_devm_release,
1001 devm_name_match, &fw_cache,
1002 dev_create_fw_entry, &todo);
1003
1004 list_for_each_entry_safe(fce, fce_next, &todo, list) {
1005 list_del(&fce->list);
1006
1007 spin_lock(&fwc->name_lock);
1008 /* only one cache entry for one firmware */
1009 if (!__fw_entry_found(fce->name)) {
1010 list_add(&fce->list, &fwc->fw_names);
1011 } else {
1012 free_fw_cache_entry(fce);
1013 fce = NULL;
1014 }
1015 spin_unlock(&fwc->name_lock);
1016
1017 if (fce)
1018 async_schedule_domain(__async_dev_cache_fw_image,
1019 (void *)fce,
1020 &fw_cache_domain);
1021 }
1022}
1023
1024static void __device_uncache_fw_images(void)
1025{
1026 struct firmware_cache *fwc = &fw_cache;
1027 struct fw_cache_entry *fce;
1028
1029 spin_lock(&fwc->name_lock);
1030 while (!list_empty(&fwc->fw_names)) {
1031 fce = list_entry(fwc->fw_names.next,
1032 struct fw_cache_entry, list);
1033 list_del(&fce->list);
1034 spin_unlock(&fwc->name_lock);
1035
1036 uncache_firmware(fce->name);
1037 free_fw_cache_entry(fce);
1038
1039 spin_lock(&fwc->name_lock);
1040 }
1041 spin_unlock(&fwc->name_lock);
1042}
1043
1044/**
1045 * device_cache_fw_images - cache devices' firmware
1046 *
1047 * If one device called request_firmware or its nowait version
1048 * successfully before, the firmware names are recored into the
1049 * device's devres link list, so device_cache_fw_images can call
1050 * cache_firmware() to cache these firmwares for the device,
1051 * then the device driver can load its firmwares easily at
1052 * time when system is not ready to complete loading firmware.
1053 */
1054static void device_cache_fw_images(void)
1055{
1056 struct firmware_cache *fwc = &fw_cache;
1057 DEFINE_WAIT(wait);
1058
1059 pr_debug("%s\n", __func__);
1060
1061 /* cancel uncache work */
1062 cancel_delayed_work_sync(&fwc->work);
1063
1064 fw_fallback_set_cache_timeout();
1065
1066 mutex_lock(&fw_lock);
1067 fwc->state = FW_LOADER_START_CACHE;
1068 dpm_for_each_dev(NULL, dev_cache_fw_image);
1069 mutex_unlock(&fw_lock);
1070
1071 /* wait for completion of caching firmware for all devices */
1072 async_synchronize_full_domain(&fw_cache_domain);
1073
1074 fw_fallback_set_default_timeout();
1075}
1076
1077/**
1078 * device_uncache_fw_images - uncache devices' firmware
1079 *
1080 * uncache all firmwares which have been cached successfully
1081 * by device_uncache_fw_images earlier
1082 */
1083static void device_uncache_fw_images(void)
1084{
1085 pr_debug("%s\n", __func__);
1086 __device_uncache_fw_images();
1087}
1088
1089static void device_uncache_fw_images_work(struct work_struct *work)
1090{
1091 device_uncache_fw_images();
1092}
1093
1094/**
1095 * device_uncache_fw_images_delay - uncache devices firmwares
1096 * @delay: number of milliseconds to delay uncache device firmwares
1097 *
1098 * uncache all devices's firmwares which has been cached successfully
1099 * by device_cache_fw_images after @delay milliseconds.
1100 */
1101static void device_uncache_fw_images_delay(unsigned long delay)
1102{
1103 queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1104 msecs_to_jiffies(delay));
1105}
1106
1107static int fw_pm_notify(struct notifier_block *notify_block,
1108 unsigned long mode, void *unused)
1109{
1110 switch (mode) {
1111 case PM_HIBERNATION_PREPARE:
1112 case PM_SUSPEND_PREPARE:
1113 case PM_RESTORE_PREPARE:
1114 /*
1115 * kill pending fallback requests with a custom fallback
1116 * to avoid stalling suspend.
1117 */
1118 kill_pending_fw_fallback_reqs(true);
1119 device_cache_fw_images();
1120 break;
1121
1122 case PM_POST_SUSPEND:
1123 case PM_POST_HIBERNATION:
1124 case PM_POST_RESTORE:
1125 /*
1126 * In case that system sleep failed and syscore_suspend is
1127 * not called.
1128 */
1129 mutex_lock(&fw_lock);
1130 fw_cache.state = FW_LOADER_NO_CACHE;
1131 mutex_unlock(&fw_lock);
1132
1133 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1134 break;
1135 }
1136
1137 return 0;
1138}
1139
1140/* stop caching firmware once syscore_suspend is reached */
1141static int fw_suspend(void)
1142{
1143 fw_cache.state = FW_LOADER_NO_CACHE;
1144 return 0;
1145}
1146
1147static struct syscore_ops fw_syscore_ops = {
1148 .suspend = fw_suspend,
1149};
1150
1151static int __init register_fw_pm_ops(void)
1152{
1153 int ret;
1154
1155 spin_lock_init(&fw_cache.name_lock);
1156 INIT_LIST_HEAD(&fw_cache.fw_names);
1157
1158 INIT_DELAYED_WORK(&fw_cache.work,
1159 device_uncache_fw_images_work);
1160
1161 fw_cache.pm_notify.notifier_call = fw_pm_notify;
1162 ret = register_pm_notifier(&fw_cache.pm_notify);
1163 if (ret)
1164 return ret;
1165
1166 register_syscore_ops(&fw_syscore_ops);
1167
1168 return ret;
1169}
1170
1171static inline void unregister_fw_pm_ops(void)
1172{
1173 unregister_syscore_ops(&fw_syscore_ops);
1174 unregister_pm_notifier(&fw_cache.pm_notify);
1175}
1176#else
1177static int fw_cache_piggyback_on_request(const char *name)
1178{
1179 return 0;
1180}
1181static inline int register_fw_pm_ops(void)
1182{
1183 return 0;
1184}
1185static inline void unregister_fw_pm_ops(void)
1186{
1187}
1188#endif
1189
1190static void __init fw_cache_init(void)
1191{
1192 spin_lock_init(&fw_cache.lock);
1193 INIT_LIST_HEAD(&fw_cache.head);
1194 fw_cache.state = FW_LOADER_NO_CACHE;
1195}
1196
1197static int fw_shutdown_notify(struct notifier_block *unused1,
1198 unsigned long unused2, void *unused3)
1199{
1200 /*
1201 * Kill all pending fallback requests to avoid both stalling shutdown,
1202 * and avoid a deadlock with the usermode_lock.
1203 */
1204 kill_pending_fw_fallback_reqs(false);
1205
1206 return NOTIFY_DONE;
1207}
1208
1209static struct notifier_block fw_shutdown_nb = {
1210 .notifier_call = fw_shutdown_notify,
1211};
1212
1213static int __init firmware_class_init(void)
1214{
1215 int ret;
1216
1217 /* No need to unfold these on exit */
1218 fw_cache_init();
1219
1220 ret = register_fw_pm_ops();
1221 if (ret)
1222 return ret;
1223
1224 ret = register_reboot_notifier(&fw_shutdown_nb);
1225 if (ret)
1226 goto out;
1227
1228 return register_sysfs_loader();
1229
1230out:
1231 unregister_fw_pm_ops();
1232 return ret;
1233}
1234
1235static void __exit firmware_class_exit(void)
1236{
1237 unregister_fw_pm_ops();
1238 unregister_reboot_notifier(&fw_shutdown_nb);
1239 unregister_sysfs_loader();
1240}
1241
1242fs_initcall(firmware_class_init);
1243module_exit(firmware_class_exit);