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/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>
31#include <linux/fs.h>
32#include <linux/async.h>
33#include <linux/pm.h>
34#include <linux/suspend.h>
35#include <linux/syscore_ops.h>
36#include <linux/reboot.h>
37#include <linux/security.h>
38#include <linux/zstd.h>
39#include <linux/xz.h>
40
41#include <generated/utsrelease.h>
42
43#include "../base.h"
44#include "firmware.h"
45#include "fallback.h"
46
47MODULE_AUTHOR("Manuel Estrada Sainz");
48MODULE_DESCRIPTION("Multi purpose firmware loading support");
49MODULE_LICENSE("GPL");
50
51struct firmware_cache {
52 /* firmware_buf instance will be added into the below list */
53 spinlock_t lock;
54 struct list_head head;
55 int state;
56
57#ifdef CONFIG_FW_CACHE
58 /*
59 * Names of firmware images which have been cached successfully
60 * will be added into the below list so that device uncache
61 * helper can trace which firmware images have been cached
62 * before.
63 */
64 spinlock_t name_lock;
65 struct list_head fw_names;
66
67 struct delayed_work work;
68
69 struct notifier_block pm_notify;
70#endif
71};
72
73struct fw_cache_entry {
74 struct list_head list;
75 const char *name;
76};
77
78struct fw_name_devm {
79 unsigned long magic;
80 const char *name;
81};
82
83static inline struct fw_priv *to_fw_priv(struct kref *ref)
84{
85 return container_of(ref, struct fw_priv, ref);
86}
87
88#define FW_LOADER_NO_CACHE 0
89#define FW_LOADER_START_CACHE 1
90
91/* fw_lock could be moved to 'struct fw_sysfs' but since it is just
92 * guarding for corner cases a global lock should be OK */
93DEFINE_MUTEX(fw_lock);
94
95struct firmware_cache fw_cache;
96
97void fw_state_init(struct fw_priv *fw_priv)
98{
99 struct fw_state *fw_st = &fw_priv->fw_st;
100
101 init_completion(&fw_st->completion);
102 fw_st->status = FW_STATUS_UNKNOWN;
103}
104
105static inline int fw_state_wait(struct fw_priv *fw_priv)
106{
107 return __fw_state_wait_common(fw_priv, MAX_SCHEDULE_TIMEOUT);
108}
109
110static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv);
111
112static struct fw_priv *__allocate_fw_priv(const char *fw_name,
113 struct firmware_cache *fwc,
114 void *dbuf,
115 size_t size,
116 size_t offset,
117 u32 opt_flags)
118{
119 struct fw_priv *fw_priv;
120
121 /* For a partial read, the buffer must be preallocated. */
122 if ((opt_flags & FW_OPT_PARTIAL) && !dbuf)
123 return NULL;
124
125 /* Only partial reads are allowed to use an offset. */
126 if (offset != 0 && !(opt_flags & FW_OPT_PARTIAL))
127 return NULL;
128
129 fw_priv = kzalloc(sizeof(*fw_priv), GFP_ATOMIC);
130 if (!fw_priv)
131 return NULL;
132
133 fw_priv->fw_name = kstrdup_const(fw_name, GFP_ATOMIC);
134 if (!fw_priv->fw_name) {
135 kfree(fw_priv);
136 return NULL;
137 }
138
139 kref_init(&fw_priv->ref);
140 fw_priv->fwc = fwc;
141 fw_priv->data = dbuf;
142 fw_priv->allocated_size = size;
143 fw_priv->offset = offset;
144 fw_priv->opt_flags = opt_flags;
145 fw_state_init(fw_priv);
146#ifdef CONFIG_FW_LOADER_USER_HELPER
147 INIT_LIST_HEAD(&fw_priv->pending_list);
148#endif
149
150 pr_debug("%s: fw-%s fw_priv=%p\n", __func__, fw_name, fw_priv);
151
152 return fw_priv;
153}
154
155static struct fw_priv *__lookup_fw_priv(const char *fw_name)
156{
157 struct fw_priv *tmp;
158 struct firmware_cache *fwc = &fw_cache;
159
160 list_for_each_entry(tmp, &fwc->head, list)
161 if (!strcmp(tmp->fw_name, fw_name))
162 return tmp;
163 return NULL;
164}
165
166/* Returns 1 for batching firmware requests with the same name */
167int alloc_lookup_fw_priv(const char *fw_name, struct firmware_cache *fwc,
168 struct fw_priv **fw_priv, void *dbuf, size_t size,
169 size_t offset, u32 opt_flags)
170{
171 struct fw_priv *tmp;
172
173 spin_lock(&fwc->lock);
174 /*
175 * Do not merge requests that are marked to be non-cached or
176 * are performing partial reads.
177 */
178 if (!(opt_flags & (FW_OPT_NOCACHE | FW_OPT_PARTIAL))) {
179 tmp = __lookup_fw_priv(fw_name);
180 if (tmp) {
181 kref_get(&tmp->ref);
182 spin_unlock(&fwc->lock);
183 *fw_priv = tmp;
184 pr_debug("batched request - sharing the same struct fw_priv and lookup for multiple requests\n");
185 return 1;
186 }
187 }
188
189 tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size, offset, opt_flags);
190 if (tmp) {
191 INIT_LIST_HEAD(&tmp->list);
192 if (!(opt_flags & FW_OPT_NOCACHE))
193 list_add(&tmp->list, &fwc->head);
194 }
195 spin_unlock(&fwc->lock);
196
197 *fw_priv = tmp;
198
199 return tmp ? 0 : -ENOMEM;
200}
201
202static void __free_fw_priv(struct kref *ref)
203 __releases(&fwc->lock)
204{
205 struct fw_priv *fw_priv = to_fw_priv(ref);
206 struct firmware_cache *fwc = fw_priv->fwc;
207
208 pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
209 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
210 (unsigned int)fw_priv->size);
211
212 list_del(&fw_priv->list);
213 spin_unlock(&fwc->lock);
214
215 if (fw_is_paged_buf(fw_priv))
216 fw_free_paged_buf(fw_priv);
217 else if (!fw_priv->allocated_size)
218 vfree(fw_priv->data);
219
220 kfree_const(fw_priv->fw_name);
221 kfree(fw_priv);
222}
223
224void free_fw_priv(struct fw_priv *fw_priv)
225{
226 struct firmware_cache *fwc = fw_priv->fwc;
227 spin_lock(&fwc->lock);
228 if (!kref_put(&fw_priv->ref, __free_fw_priv))
229 spin_unlock(&fwc->lock);
230}
231
232#ifdef CONFIG_FW_LOADER_PAGED_BUF
233bool fw_is_paged_buf(struct fw_priv *fw_priv)
234{
235 return fw_priv->is_paged_buf;
236}
237
238void fw_free_paged_buf(struct fw_priv *fw_priv)
239{
240 int i;
241
242 if (!fw_priv->pages)
243 return;
244
245 vunmap(fw_priv->data);
246
247 for (i = 0; i < fw_priv->nr_pages; i++)
248 __free_page(fw_priv->pages[i]);
249 kvfree(fw_priv->pages);
250 fw_priv->pages = NULL;
251 fw_priv->page_array_size = 0;
252 fw_priv->nr_pages = 0;
253 fw_priv->data = NULL;
254 fw_priv->size = 0;
255}
256
257int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed)
258{
259 /* If the array of pages is too small, grow it */
260 if (fw_priv->page_array_size < pages_needed) {
261 int new_array_size = max(pages_needed,
262 fw_priv->page_array_size * 2);
263 struct page **new_pages;
264
265 new_pages = kvmalloc_array(new_array_size, sizeof(void *),
266 GFP_KERNEL);
267 if (!new_pages)
268 return -ENOMEM;
269 memcpy(new_pages, fw_priv->pages,
270 fw_priv->page_array_size * sizeof(void *));
271 memset(&new_pages[fw_priv->page_array_size], 0, sizeof(void *) *
272 (new_array_size - fw_priv->page_array_size));
273 kvfree(fw_priv->pages);
274 fw_priv->pages = new_pages;
275 fw_priv->page_array_size = new_array_size;
276 }
277
278 while (fw_priv->nr_pages < pages_needed) {
279 fw_priv->pages[fw_priv->nr_pages] =
280 alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
281
282 if (!fw_priv->pages[fw_priv->nr_pages])
283 return -ENOMEM;
284 fw_priv->nr_pages++;
285 }
286
287 return 0;
288}
289
290int fw_map_paged_buf(struct fw_priv *fw_priv)
291{
292 /* one pages buffer should be mapped/unmapped only once */
293 if (!fw_priv->pages)
294 return 0;
295
296 vunmap(fw_priv->data);
297 fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages, 0,
298 PAGE_KERNEL_RO);
299 if (!fw_priv->data)
300 return -ENOMEM;
301
302 return 0;
303}
304#endif
305
306/*
307 * ZSTD-compressed firmware support
308 */
309#ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD
310static int fw_decompress_zstd(struct device *dev, struct fw_priv *fw_priv,
311 size_t in_size, const void *in_buffer)
312{
313 size_t len, out_size, workspace_size;
314 void *workspace, *out_buf;
315 zstd_dctx *ctx;
316 int err;
317
318 if (fw_priv->allocated_size) {
319 out_size = fw_priv->allocated_size;
320 out_buf = fw_priv->data;
321 } else {
322 zstd_frame_header params;
323
324 if (zstd_get_frame_header(¶ms, in_buffer, in_size) ||
325 params.frameContentSize == ZSTD_CONTENTSIZE_UNKNOWN) {
326 dev_dbg(dev, "%s: invalid zstd header\n", __func__);
327 return -EINVAL;
328 }
329 out_size = params.frameContentSize;
330 out_buf = vzalloc(out_size);
331 if (!out_buf)
332 return -ENOMEM;
333 }
334
335 workspace_size = zstd_dctx_workspace_bound();
336 workspace = kvzalloc(workspace_size, GFP_KERNEL);
337 if (!workspace) {
338 err = -ENOMEM;
339 goto error;
340 }
341
342 ctx = zstd_init_dctx(workspace, workspace_size);
343 if (!ctx) {
344 dev_dbg(dev, "%s: failed to initialize context\n", __func__);
345 err = -EINVAL;
346 goto error;
347 }
348
349 len = zstd_decompress_dctx(ctx, out_buf, out_size, in_buffer, in_size);
350 if (zstd_is_error(len)) {
351 dev_dbg(dev, "%s: failed to decompress: %d\n", __func__,
352 zstd_get_error_code(len));
353 err = -EINVAL;
354 goto error;
355 }
356
357 if (!fw_priv->allocated_size)
358 fw_priv->data = out_buf;
359 fw_priv->size = len;
360 err = 0;
361
362 error:
363 kvfree(workspace);
364 if (err && !fw_priv->allocated_size)
365 vfree(out_buf);
366 return err;
367}
368#endif /* CONFIG_FW_LOADER_COMPRESS_ZSTD */
369
370/*
371 * XZ-compressed firmware support
372 */
373#ifdef CONFIG_FW_LOADER_COMPRESS_XZ
374/* show an error and return the standard error code */
375static int fw_decompress_xz_error(struct device *dev, enum xz_ret xz_ret)
376{
377 if (xz_ret != XZ_STREAM_END) {
378 dev_warn(dev, "xz decompression failed (xz_ret=%d)\n", xz_ret);
379 return xz_ret == XZ_MEM_ERROR ? -ENOMEM : -EINVAL;
380 }
381 return 0;
382}
383
384/* single-shot decompression onto the pre-allocated buffer */
385static int fw_decompress_xz_single(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
392 xz_dec = xz_dec_init(XZ_SINGLE, (u32)-1);
393 if (!xz_dec)
394 return -ENOMEM;
395
396 xz_buf.in_size = in_size;
397 xz_buf.in = in_buffer;
398 xz_buf.in_pos = 0;
399 xz_buf.out_size = fw_priv->allocated_size;
400 xz_buf.out = fw_priv->data;
401 xz_buf.out_pos = 0;
402
403 xz_ret = xz_dec_run(xz_dec, &xz_buf);
404 xz_dec_end(xz_dec);
405
406 fw_priv->size = xz_buf.out_pos;
407 return fw_decompress_xz_error(dev, xz_ret);
408}
409
410/* decompression on paged buffer and map it */
411static int fw_decompress_xz_pages(struct device *dev, struct fw_priv *fw_priv,
412 size_t in_size, const void *in_buffer)
413{
414 struct xz_dec *xz_dec;
415 struct xz_buf xz_buf;
416 enum xz_ret xz_ret;
417 struct page *page;
418 int err = 0;
419
420 xz_dec = xz_dec_init(XZ_DYNALLOC, (u32)-1);
421 if (!xz_dec)
422 return -ENOMEM;
423
424 xz_buf.in_size = in_size;
425 xz_buf.in = in_buffer;
426 xz_buf.in_pos = 0;
427
428 fw_priv->is_paged_buf = true;
429 fw_priv->size = 0;
430 do {
431 if (fw_grow_paged_buf(fw_priv, fw_priv->nr_pages + 1)) {
432 err = -ENOMEM;
433 goto out;
434 }
435
436 /* decompress onto the new allocated page */
437 page = fw_priv->pages[fw_priv->nr_pages - 1];
438 xz_buf.out = kmap_local_page(page);
439 xz_buf.out_pos = 0;
440 xz_buf.out_size = PAGE_SIZE;
441 xz_ret = xz_dec_run(xz_dec, &xz_buf);
442 kunmap_local(xz_buf.out);
443 fw_priv->size += xz_buf.out_pos;
444 /* partial decompression means either end or error */
445 if (xz_buf.out_pos != PAGE_SIZE)
446 break;
447 } while (xz_ret == XZ_OK);
448
449 err = fw_decompress_xz_error(dev, xz_ret);
450 if (!err)
451 err = fw_map_paged_buf(fw_priv);
452
453 out:
454 xz_dec_end(xz_dec);
455 return err;
456}
457
458static int fw_decompress_xz(struct device *dev, struct fw_priv *fw_priv,
459 size_t in_size, const void *in_buffer)
460{
461 /* if the buffer is pre-allocated, we can perform in single-shot mode */
462 if (fw_priv->data)
463 return fw_decompress_xz_single(dev, fw_priv, in_size, in_buffer);
464 else
465 return fw_decompress_xz_pages(dev, fw_priv, in_size, in_buffer);
466}
467#endif /* CONFIG_FW_LOADER_COMPRESS_XZ */
468
469/* direct firmware loading support */
470static char fw_path_para[256];
471static const char * const fw_path[] = {
472 fw_path_para,
473 "/lib/firmware/updates/" UTS_RELEASE,
474 "/lib/firmware/updates",
475 "/lib/firmware/" UTS_RELEASE,
476 "/lib/firmware"
477};
478
479/*
480 * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
481 * from kernel command line because firmware_class is generally built in
482 * kernel instead of module.
483 */
484module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
485MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
486
487static int
488fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv,
489 const char *suffix,
490 int (*decompress)(struct device *dev,
491 struct fw_priv *fw_priv,
492 size_t in_size,
493 const void *in_buffer))
494{
495 size_t size;
496 int i, len;
497 int rc = -ENOENT;
498 char *path;
499 size_t msize = INT_MAX;
500 void *buffer = NULL;
501
502 /* Already populated data member means we're loading into a buffer */
503 if (!decompress && fw_priv->data) {
504 buffer = fw_priv->data;
505 msize = fw_priv->allocated_size;
506 }
507
508 path = __getname();
509 if (!path)
510 return -ENOMEM;
511
512 wait_for_initramfs();
513 for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
514 size_t file_size = 0;
515 size_t *file_size_ptr = NULL;
516
517 /* skip the unset customized path */
518 if (!fw_path[i][0])
519 continue;
520
521 len = snprintf(path, PATH_MAX, "%s/%s%s",
522 fw_path[i], fw_priv->fw_name, suffix);
523 if (len >= PATH_MAX) {
524 rc = -ENAMETOOLONG;
525 break;
526 }
527
528 fw_priv->size = 0;
529
530 /*
531 * The total file size is only examined when doing a partial
532 * read; the "full read" case needs to fail if the whole
533 * firmware was not completely loaded.
534 */
535 if ((fw_priv->opt_flags & FW_OPT_PARTIAL) && buffer)
536 file_size_ptr = &file_size;
537
538 /* load firmware files from the mount namespace of init */
539 rc = kernel_read_file_from_path_initns(path, fw_priv->offset,
540 &buffer, msize,
541 file_size_ptr,
542 READING_FIRMWARE);
543 if (rc < 0) {
544 if (rc != -ENOENT)
545 dev_warn(device, "loading %s failed with error %d\n",
546 path, rc);
547 else
548 dev_dbg(device, "loading %s failed for no such file or directory.\n",
549 path);
550 continue;
551 }
552 size = rc;
553 rc = 0;
554
555 dev_dbg(device, "Loading firmware from %s\n", path);
556 if (decompress) {
557 dev_dbg(device, "f/w decompressing %s\n",
558 fw_priv->fw_name);
559 rc = decompress(device, fw_priv, size, buffer);
560 /* discard the superfluous original content */
561 vfree(buffer);
562 buffer = NULL;
563 if (rc) {
564 fw_free_paged_buf(fw_priv);
565 continue;
566 }
567 } else {
568 dev_dbg(device, "direct-loading %s\n",
569 fw_priv->fw_name);
570 if (!fw_priv->data)
571 fw_priv->data = buffer;
572 fw_priv->size = size;
573 }
574 fw_state_done(fw_priv);
575 break;
576 }
577 __putname(path);
578
579 return rc;
580}
581
582/* firmware holds the ownership of pages */
583static void firmware_free_data(const struct firmware *fw)
584{
585 /* Loaded directly? */
586 if (!fw->priv) {
587 vfree(fw->data);
588 return;
589 }
590 free_fw_priv(fw->priv);
591}
592
593/* store the pages buffer info firmware from buf */
594static void fw_set_page_data(struct fw_priv *fw_priv, struct firmware *fw)
595{
596 fw->priv = fw_priv;
597 fw->size = fw_priv->size;
598 fw->data = fw_priv->data;
599
600 pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
601 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
602 (unsigned int)fw_priv->size);
603}
604
605#ifdef CONFIG_FW_CACHE
606static void fw_name_devm_release(struct device *dev, void *res)
607{
608 struct fw_name_devm *fwn = res;
609
610 if (fwn->magic == (unsigned long)&fw_cache)
611 pr_debug("%s: fw_name-%s devm-%p released\n",
612 __func__, fwn->name, res);
613 kfree_const(fwn->name);
614}
615
616static int fw_devm_match(struct device *dev, void *res,
617 void *match_data)
618{
619 struct fw_name_devm *fwn = res;
620
621 return (fwn->magic == (unsigned long)&fw_cache) &&
622 !strcmp(fwn->name, match_data);
623}
624
625static struct fw_name_devm *fw_find_devm_name(struct device *dev,
626 const char *name)
627{
628 struct fw_name_devm *fwn;
629
630 fwn = devres_find(dev, fw_name_devm_release,
631 fw_devm_match, (void *)name);
632 return fwn;
633}
634
635static bool fw_cache_is_setup(struct device *dev, const char *name)
636{
637 struct fw_name_devm *fwn;
638
639 fwn = fw_find_devm_name(dev, name);
640 if (fwn)
641 return true;
642
643 return false;
644}
645
646/* add firmware name into devres list */
647static int fw_add_devm_name(struct device *dev, const char *name)
648{
649 struct fw_name_devm *fwn;
650
651 if (fw_cache_is_setup(dev, name))
652 return 0;
653
654 fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm),
655 GFP_KERNEL);
656 if (!fwn)
657 return -ENOMEM;
658 fwn->name = kstrdup_const(name, GFP_KERNEL);
659 if (!fwn->name) {
660 devres_free(fwn);
661 return -ENOMEM;
662 }
663
664 fwn->magic = (unsigned long)&fw_cache;
665 devres_add(dev, fwn);
666
667 return 0;
668}
669#else
670static bool fw_cache_is_setup(struct device *dev, const char *name)
671{
672 return false;
673}
674
675static int fw_add_devm_name(struct device *dev, const char *name)
676{
677 return 0;
678}
679#endif
680
681int assign_fw(struct firmware *fw, struct device *device)
682{
683 struct fw_priv *fw_priv = fw->priv;
684 int ret;
685
686 mutex_lock(&fw_lock);
687 if (!fw_priv->size || fw_state_is_aborted(fw_priv)) {
688 mutex_unlock(&fw_lock);
689 return -ENOENT;
690 }
691
692 /*
693 * add firmware name into devres list so that we can auto cache
694 * and uncache firmware for device.
695 *
696 * device may has been deleted already, but the problem
697 * should be fixed in devres or driver core.
698 */
699 /* don't cache firmware handled without uevent */
700 if (device && (fw_priv->opt_flags & FW_OPT_UEVENT) &&
701 !(fw_priv->opt_flags & FW_OPT_NOCACHE)) {
702 ret = fw_add_devm_name(device, fw_priv->fw_name);
703 if (ret) {
704 mutex_unlock(&fw_lock);
705 return ret;
706 }
707 }
708
709 /*
710 * After caching firmware image is started, let it piggyback
711 * on request firmware.
712 */
713 if (!(fw_priv->opt_flags & FW_OPT_NOCACHE) &&
714 fw_priv->fwc->state == FW_LOADER_START_CACHE)
715 fw_cache_piggyback_on_request(fw_priv);
716
717 /* pass the pages buffer to driver at the last minute */
718 fw_set_page_data(fw_priv, fw);
719 mutex_unlock(&fw_lock);
720 return 0;
721}
722
723/* prepare firmware and firmware_buf structs;
724 * return 0 if a firmware is already assigned, 1 if need to load one,
725 * or a negative error code
726 */
727static int
728_request_firmware_prepare(struct firmware **firmware_p, const char *name,
729 struct device *device, void *dbuf, size_t size,
730 size_t offset, u32 opt_flags)
731{
732 struct firmware *firmware;
733 struct fw_priv *fw_priv;
734 int ret;
735
736 *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
737 if (!firmware) {
738 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
739 __func__);
740 return -ENOMEM;
741 }
742
743 if (firmware_request_builtin_buf(firmware, name, dbuf, size)) {
744 dev_dbg(device, "using built-in %s\n", name);
745 return 0; /* assigned */
746 }
747
748 ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv, dbuf, size,
749 offset, opt_flags);
750
751 /*
752 * bind with 'priv' now to avoid warning in failure path
753 * of requesting firmware.
754 */
755 firmware->priv = fw_priv;
756
757 if (ret > 0) {
758 ret = fw_state_wait(fw_priv);
759 if (!ret) {
760 fw_set_page_data(fw_priv, firmware);
761 return 0; /* assigned */
762 }
763 }
764
765 if (ret < 0)
766 return ret;
767 return 1; /* need to load */
768}
769
770/*
771 * Batched requests need only one wake, we need to do this step last due to the
772 * fallback mechanism. The buf is protected with kref_get(), and it won't be
773 * released until the last user calls release_firmware().
774 *
775 * Failed batched requests are possible as well, in such cases we just share
776 * the struct fw_priv and won't release it until all requests are woken
777 * and have gone through this same path.
778 */
779static void fw_abort_batch_reqs(struct firmware *fw)
780{
781 struct fw_priv *fw_priv;
782
783 /* Loaded directly? */
784 if (!fw || !fw->priv)
785 return;
786
787 fw_priv = fw->priv;
788 mutex_lock(&fw_lock);
789 if (!fw_state_is_aborted(fw_priv))
790 fw_state_aborted(fw_priv);
791 mutex_unlock(&fw_lock);
792}
793
794/* called from request_firmware() and request_firmware_work_func() */
795static int
796_request_firmware(const struct firmware **firmware_p, const char *name,
797 struct device *device, void *buf, size_t size,
798 size_t offset, u32 opt_flags)
799{
800 struct firmware *fw = NULL;
801 struct cred *kern_cred = NULL;
802 const struct cred *old_cred;
803 bool nondirect = false;
804 int ret;
805
806 if (!firmware_p)
807 return -EINVAL;
808
809 if (!name || name[0] == '\0') {
810 ret = -EINVAL;
811 goto out;
812 }
813
814 ret = _request_firmware_prepare(&fw, name, device, buf, size,
815 offset, opt_flags);
816 if (ret <= 0) /* error or already assigned */
817 goto out;
818
819 /*
820 * We are about to try to access the firmware file. Because we may have been
821 * called by a driver when serving an unrelated request from userland, we use
822 * the kernel credentials to read the file.
823 */
824 kern_cred = prepare_kernel_cred(&init_task);
825 if (!kern_cred) {
826 ret = -ENOMEM;
827 goto out;
828 }
829 old_cred = override_creds(kern_cred);
830
831 ret = fw_get_filesystem_firmware(device, fw->priv, "", NULL);
832
833 /* Only full reads can support decompression, platform, and sysfs. */
834 if (!(opt_flags & FW_OPT_PARTIAL))
835 nondirect = true;
836
837#ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD
838 if (ret == -ENOENT && nondirect)
839 ret = fw_get_filesystem_firmware(device, fw->priv, ".zst",
840 fw_decompress_zstd);
841#endif
842#ifdef CONFIG_FW_LOADER_COMPRESS_XZ
843 if (ret == -ENOENT && nondirect)
844 ret = fw_get_filesystem_firmware(device, fw->priv, ".xz",
845 fw_decompress_xz);
846#endif
847 if (ret == -ENOENT && nondirect)
848 ret = firmware_fallback_platform(fw->priv);
849
850 if (ret) {
851 if (!(opt_flags & FW_OPT_NO_WARN))
852 dev_warn(device,
853 "Direct firmware load for %s failed with error %d\n",
854 name, ret);
855 if (nondirect)
856 ret = firmware_fallback_sysfs(fw, name, device,
857 opt_flags, ret);
858 } else
859 ret = assign_fw(fw, device);
860
861 revert_creds(old_cred);
862 put_cred(kern_cred);
863
864 out:
865 if (ret < 0) {
866 fw_abort_batch_reqs(fw);
867 release_firmware(fw);
868 fw = NULL;
869 }
870
871 *firmware_p = fw;
872 return ret;
873}
874
875/**
876 * request_firmware() - send firmware request and wait for it
877 * @firmware_p: pointer to firmware image
878 * @name: name of firmware file
879 * @device: device for which firmware is being loaded
880 *
881 * @firmware_p will be used to return a firmware image by the name
882 * of @name for device @device.
883 *
884 * Should be called from user context where sleeping is allowed.
885 *
886 * @name will be used as $FIRMWARE in the uevent environment and
887 * should be distinctive enough not to be confused with any other
888 * firmware image for this or any other device.
889 *
890 * Caller must hold the reference count of @device.
891 *
892 * The function can be called safely inside device's suspend and
893 * resume callback.
894 **/
895int
896request_firmware(const struct firmware **firmware_p, const char *name,
897 struct device *device)
898{
899 int ret;
900
901 /* Need to pin this module until return */
902 __module_get(THIS_MODULE);
903 ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
904 FW_OPT_UEVENT);
905 module_put(THIS_MODULE);
906 return ret;
907}
908EXPORT_SYMBOL(request_firmware);
909
910/**
911 * firmware_request_nowarn() - request for an optional fw module
912 * @firmware: pointer to firmware image
913 * @name: name of firmware file
914 * @device: device for which firmware is being loaded
915 *
916 * This function is similar in behaviour to request_firmware(), except it
917 * doesn't produce warning messages when the file is not found. The sysfs
918 * fallback mechanism is enabled if direct filesystem lookup fails. However,
919 * failures to find the firmware file with it are still suppressed. It is
920 * therefore up to the driver to check for the return value of this call and to
921 * decide when to inform the users of errors.
922 **/
923int firmware_request_nowarn(const struct firmware **firmware, const char *name,
924 struct device *device)
925{
926 int ret;
927
928 /* Need to pin this module until return */
929 __module_get(THIS_MODULE);
930 ret = _request_firmware(firmware, name, device, NULL, 0, 0,
931 FW_OPT_UEVENT | FW_OPT_NO_WARN);
932 module_put(THIS_MODULE);
933 return ret;
934}
935EXPORT_SYMBOL_GPL(firmware_request_nowarn);
936
937/**
938 * request_firmware_direct() - load firmware directly without usermode helper
939 * @firmware_p: pointer to firmware image
940 * @name: name of firmware file
941 * @device: device for which firmware is being loaded
942 *
943 * This function works pretty much like request_firmware(), but this doesn't
944 * fall back to usermode helper even if the firmware couldn't be loaded
945 * directly from fs. Hence it's useful for loading optional firmwares, which
946 * aren't always present, without extra long timeouts of udev.
947 **/
948int request_firmware_direct(const struct firmware **firmware_p,
949 const char *name, struct device *device)
950{
951 int ret;
952
953 __module_get(THIS_MODULE);
954 ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
955 FW_OPT_UEVENT | FW_OPT_NO_WARN |
956 FW_OPT_NOFALLBACK_SYSFS);
957 module_put(THIS_MODULE);
958 return ret;
959}
960EXPORT_SYMBOL_GPL(request_firmware_direct);
961
962/**
963 * firmware_request_platform() - request firmware with platform-fw fallback
964 * @firmware: pointer to firmware image
965 * @name: name of firmware file
966 * @device: device for which firmware is being loaded
967 *
968 * This function is similar in behaviour to request_firmware, except that if
969 * direct filesystem lookup fails, it will fallback to looking for a copy of the
970 * requested firmware embedded in the platform's main (e.g. UEFI) firmware.
971 **/
972int firmware_request_platform(const struct firmware **firmware,
973 const char *name, struct device *device)
974{
975 int ret;
976
977 /* Need to pin this module until return */
978 __module_get(THIS_MODULE);
979 ret = _request_firmware(firmware, name, device, NULL, 0, 0,
980 FW_OPT_UEVENT | FW_OPT_FALLBACK_PLATFORM);
981 module_put(THIS_MODULE);
982 return ret;
983}
984EXPORT_SYMBOL_GPL(firmware_request_platform);
985
986/**
987 * firmware_request_cache() - cache firmware for suspend so resume can use it
988 * @name: name of firmware file
989 * @device: device for which firmware should be cached for
990 *
991 * There are some devices with an optimization that enables the device to not
992 * require loading firmware on system reboot. This optimization may still
993 * require the firmware present on resume from suspend. This routine can be
994 * used to ensure the firmware is present on resume from suspend in these
995 * situations. This helper is not compatible with drivers which use
996 * request_firmware_into_buf() or request_firmware_nowait() with no uevent set.
997 **/
998int firmware_request_cache(struct device *device, const char *name)
999{
1000 int ret;
1001
1002 mutex_lock(&fw_lock);
1003 ret = fw_add_devm_name(device, name);
1004 mutex_unlock(&fw_lock);
1005
1006 return ret;
1007}
1008EXPORT_SYMBOL_GPL(firmware_request_cache);
1009
1010/**
1011 * request_firmware_into_buf() - load firmware into a previously allocated buffer
1012 * @firmware_p: pointer to firmware image
1013 * @name: name of firmware file
1014 * @device: device for which firmware is being loaded and DMA region allocated
1015 * @buf: address of buffer to load firmware into
1016 * @size: size of buffer
1017 *
1018 * This function works pretty much like request_firmware(), but it doesn't
1019 * allocate a buffer to hold the firmware data. Instead, the firmware
1020 * is loaded directly into the buffer pointed to by @buf and the @firmware_p
1021 * data member is pointed at @buf.
1022 *
1023 * This function doesn't cache firmware either.
1024 */
1025int
1026request_firmware_into_buf(const struct firmware **firmware_p, const char *name,
1027 struct device *device, void *buf, size_t size)
1028{
1029 int ret;
1030
1031 if (fw_cache_is_setup(device, name))
1032 return -EOPNOTSUPP;
1033
1034 __module_get(THIS_MODULE);
1035 ret = _request_firmware(firmware_p, name, device, buf, size, 0,
1036 FW_OPT_UEVENT | FW_OPT_NOCACHE);
1037 module_put(THIS_MODULE);
1038 return ret;
1039}
1040EXPORT_SYMBOL(request_firmware_into_buf);
1041
1042/**
1043 * request_partial_firmware_into_buf() - load partial firmware into a previously allocated buffer
1044 * @firmware_p: pointer to firmware image
1045 * @name: name of firmware file
1046 * @device: device for which firmware is being loaded and DMA region allocated
1047 * @buf: address of buffer to load firmware into
1048 * @size: size of buffer
1049 * @offset: offset into file to read
1050 *
1051 * This function works pretty much like request_firmware_into_buf except
1052 * it allows a partial read of the file.
1053 */
1054int
1055request_partial_firmware_into_buf(const struct firmware **firmware_p,
1056 const char *name, struct device *device,
1057 void *buf, size_t size, size_t offset)
1058{
1059 int ret;
1060
1061 if (fw_cache_is_setup(device, name))
1062 return -EOPNOTSUPP;
1063
1064 __module_get(THIS_MODULE);
1065 ret = _request_firmware(firmware_p, name, device, buf, size, offset,
1066 FW_OPT_UEVENT | FW_OPT_NOCACHE |
1067 FW_OPT_PARTIAL);
1068 module_put(THIS_MODULE);
1069 return ret;
1070}
1071EXPORT_SYMBOL(request_partial_firmware_into_buf);
1072
1073/**
1074 * release_firmware() - release the resource associated with a firmware image
1075 * @fw: firmware resource to release
1076 **/
1077void release_firmware(const struct firmware *fw)
1078{
1079 if (fw) {
1080 if (!firmware_is_builtin(fw))
1081 firmware_free_data(fw);
1082 kfree(fw);
1083 }
1084}
1085EXPORT_SYMBOL(release_firmware);
1086
1087/* Async support */
1088struct firmware_work {
1089 struct work_struct work;
1090 struct module *module;
1091 const char *name;
1092 struct device *device;
1093 void *context;
1094 void (*cont)(const struct firmware *fw, void *context);
1095 u32 opt_flags;
1096};
1097
1098static void request_firmware_work_func(struct work_struct *work)
1099{
1100 struct firmware_work *fw_work;
1101 const struct firmware *fw;
1102
1103 fw_work = container_of(work, struct firmware_work, work);
1104
1105 _request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0, 0,
1106 fw_work->opt_flags);
1107 fw_work->cont(fw, fw_work->context);
1108 put_device(fw_work->device); /* taken in request_firmware_nowait() */
1109
1110 module_put(fw_work->module);
1111 kfree_const(fw_work->name);
1112 kfree(fw_work);
1113}
1114
1115/**
1116 * request_firmware_nowait() - asynchronous version of request_firmware
1117 * @module: module requesting the firmware
1118 * @uevent: sends uevent to copy the firmware image if this flag
1119 * is non-zero else the firmware copy must be done manually.
1120 * @name: name of firmware file
1121 * @device: device for which firmware is being loaded
1122 * @gfp: allocation flags
1123 * @context: will be passed over to @cont, and
1124 * @fw may be %NULL if firmware request fails.
1125 * @cont: function will be called asynchronously when the firmware
1126 * request is over.
1127 *
1128 * Caller must hold the reference count of @device.
1129 *
1130 * Asynchronous variant of request_firmware() for user contexts:
1131 * - sleep for as small periods as possible since it may
1132 * increase kernel boot time of built-in device drivers
1133 * requesting firmware in their ->probe() methods, if
1134 * @gfp is GFP_KERNEL.
1135 *
1136 * - can't sleep at all if @gfp is GFP_ATOMIC.
1137 **/
1138int
1139request_firmware_nowait(
1140 struct module *module, bool uevent,
1141 const char *name, struct device *device, gfp_t gfp, void *context,
1142 void (*cont)(const struct firmware *fw, void *context))
1143{
1144 struct firmware_work *fw_work;
1145
1146 fw_work = kzalloc(sizeof(struct firmware_work), gfp);
1147 if (!fw_work)
1148 return -ENOMEM;
1149
1150 fw_work->module = module;
1151 fw_work->name = kstrdup_const(name, gfp);
1152 if (!fw_work->name) {
1153 kfree(fw_work);
1154 return -ENOMEM;
1155 }
1156 fw_work->device = device;
1157 fw_work->context = context;
1158 fw_work->cont = cont;
1159 fw_work->opt_flags = FW_OPT_NOWAIT |
1160 (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
1161
1162 if (!uevent && fw_cache_is_setup(device, name)) {
1163 kfree_const(fw_work->name);
1164 kfree(fw_work);
1165 return -EOPNOTSUPP;
1166 }
1167
1168 if (!try_module_get(module)) {
1169 kfree_const(fw_work->name);
1170 kfree(fw_work);
1171 return -EFAULT;
1172 }
1173
1174 get_device(fw_work->device);
1175 INIT_WORK(&fw_work->work, request_firmware_work_func);
1176 schedule_work(&fw_work->work);
1177 return 0;
1178}
1179EXPORT_SYMBOL(request_firmware_nowait);
1180
1181#ifdef CONFIG_FW_CACHE
1182static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1183
1184/**
1185 * cache_firmware() - cache one firmware image in kernel memory space
1186 * @fw_name: the firmware image name
1187 *
1188 * Cache firmware in kernel memory so that drivers can use it when
1189 * system isn't ready for them to request firmware image from userspace.
1190 * Once it returns successfully, driver can use request_firmware or its
1191 * nowait version to get the cached firmware without any interacting
1192 * with userspace
1193 *
1194 * Return 0 if the firmware image has been cached successfully
1195 * Return !0 otherwise
1196 *
1197 */
1198static int cache_firmware(const char *fw_name)
1199{
1200 int ret;
1201 const struct firmware *fw;
1202
1203 pr_debug("%s: %s\n", __func__, fw_name);
1204
1205 ret = request_firmware(&fw, fw_name, NULL);
1206 if (!ret)
1207 kfree(fw);
1208
1209 pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1210
1211 return ret;
1212}
1213
1214static struct fw_priv *lookup_fw_priv(const char *fw_name)
1215{
1216 struct fw_priv *tmp;
1217 struct firmware_cache *fwc = &fw_cache;
1218
1219 spin_lock(&fwc->lock);
1220 tmp = __lookup_fw_priv(fw_name);
1221 spin_unlock(&fwc->lock);
1222
1223 return tmp;
1224}
1225
1226/**
1227 * uncache_firmware() - remove one cached firmware image
1228 * @fw_name: the firmware image name
1229 *
1230 * Uncache one firmware image which has been cached successfully
1231 * before.
1232 *
1233 * Return 0 if the firmware cache has been removed successfully
1234 * Return !0 otherwise
1235 *
1236 */
1237static int uncache_firmware(const char *fw_name)
1238{
1239 struct fw_priv *fw_priv;
1240 struct firmware fw;
1241
1242 pr_debug("%s: %s\n", __func__, fw_name);
1243
1244 if (firmware_request_builtin(&fw, fw_name))
1245 return 0;
1246
1247 fw_priv = lookup_fw_priv(fw_name);
1248 if (fw_priv) {
1249 free_fw_priv(fw_priv);
1250 return 0;
1251 }
1252
1253 return -EINVAL;
1254}
1255
1256static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1257{
1258 struct fw_cache_entry *fce;
1259
1260 fce = kzalloc(sizeof(*fce), GFP_ATOMIC);
1261 if (!fce)
1262 goto exit;
1263
1264 fce->name = kstrdup_const(name, GFP_ATOMIC);
1265 if (!fce->name) {
1266 kfree(fce);
1267 fce = NULL;
1268 goto exit;
1269 }
1270exit:
1271 return fce;
1272}
1273
1274static int __fw_entry_found(const char *name)
1275{
1276 struct firmware_cache *fwc = &fw_cache;
1277 struct fw_cache_entry *fce;
1278
1279 list_for_each_entry(fce, &fwc->fw_names, list) {
1280 if (!strcmp(fce->name, name))
1281 return 1;
1282 }
1283 return 0;
1284}
1285
1286static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv)
1287{
1288 const char *name = fw_priv->fw_name;
1289 struct firmware_cache *fwc = fw_priv->fwc;
1290 struct fw_cache_entry *fce;
1291
1292 spin_lock(&fwc->name_lock);
1293 if (__fw_entry_found(name))
1294 goto found;
1295
1296 fce = alloc_fw_cache_entry(name);
1297 if (fce) {
1298 list_add(&fce->list, &fwc->fw_names);
1299 kref_get(&fw_priv->ref);
1300 pr_debug("%s: fw: %s\n", __func__, name);
1301 }
1302found:
1303 spin_unlock(&fwc->name_lock);
1304}
1305
1306static void free_fw_cache_entry(struct fw_cache_entry *fce)
1307{
1308 kfree_const(fce->name);
1309 kfree(fce);
1310}
1311
1312static void __async_dev_cache_fw_image(void *fw_entry,
1313 async_cookie_t cookie)
1314{
1315 struct fw_cache_entry *fce = fw_entry;
1316 struct firmware_cache *fwc = &fw_cache;
1317 int ret;
1318
1319 ret = cache_firmware(fce->name);
1320 if (ret) {
1321 spin_lock(&fwc->name_lock);
1322 list_del(&fce->list);
1323 spin_unlock(&fwc->name_lock);
1324
1325 free_fw_cache_entry(fce);
1326 }
1327}
1328
1329/* called with dev->devres_lock held */
1330static void dev_create_fw_entry(struct device *dev, void *res,
1331 void *data)
1332{
1333 struct fw_name_devm *fwn = res;
1334 const char *fw_name = fwn->name;
1335 struct list_head *head = data;
1336 struct fw_cache_entry *fce;
1337
1338 fce = alloc_fw_cache_entry(fw_name);
1339 if (fce)
1340 list_add(&fce->list, head);
1341}
1342
1343static int devm_name_match(struct device *dev, void *res,
1344 void *match_data)
1345{
1346 struct fw_name_devm *fwn = res;
1347 return (fwn->magic == (unsigned long)match_data);
1348}
1349
1350static void dev_cache_fw_image(struct device *dev, void *data)
1351{
1352 LIST_HEAD(todo);
1353 struct fw_cache_entry *fce;
1354 struct fw_cache_entry *fce_next;
1355 struct firmware_cache *fwc = &fw_cache;
1356
1357 devres_for_each_res(dev, fw_name_devm_release,
1358 devm_name_match, &fw_cache,
1359 dev_create_fw_entry, &todo);
1360
1361 list_for_each_entry_safe(fce, fce_next, &todo, list) {
1362 list_del(&fce->list);
1363
1364 spin_lock(&fwc->name_lock);
1365 /* only one cache entry for one firmware */
1366 if (!__fw_entry_found(fce->name)) {
1367 list_add(&fce->list, &fwc->fw_names);
1368 } else {
1369 free_fw_cache_entry(fce);
1370 fce = NULL;
1371 }
1372 spin_unlock(&fwc->name_lock);
1373
1374 if (fce)
1375 async_schedule_domain(__async_dev_cache_fw_image,
1376 (void *)fce,
1377 &fw_cache_domain);
1378 }
1379}
1380
1381static void __device_uncache_fw_images(void)
1382{
1383 struct firmware_cache *fwc = &fw_cache;
1384 struct fw_cache_entry *fce;
1385
1386 spin_lock(&fwc->name_lock);
1387 while (!list_empty(&fwc->fw_names)) {
1388 fce = list_entry(fwc->fw_names.next,
1389 struct fw_cache_entry, list);
1390 list_del(&fce->list);
1391 spin_unlock(&fwc->name_lock);
1392
1393 uncache_firmware(fce->name);
1394 free_fw_cache_entry(fce);
1395
1396 spin_lock(&fwc->name_lock);
1397 }
1398 spin_unlock(&fwc->name_lock);
1399}
1400
1401/**
1402 * device_cache_fw_images() - cache devices' firmware
1403 *
1404 * If one device called request_firmware or its nowait version
1405 * successfully before, the firmware names are recored into the
1406 * device's devres link list, so device_cache_fw_images can call
1407 * cache_firmware() to cache these firmwares for the device,
1408 * then the device driver can load its firmwares easily at
1409 * time when system is not ready to complete loading firmware.
1410 */
1411static void device_cache_fw_images(void)
1412{
1413 struct firmware_cache *fwc = &fw_cache;
1414 DEFINE_WAIT(wait);
1415
1416 pr_debug("%s\n", __func__);
1417
1418 /* cancel uncache work */
1419 cancel_delayed_work_sync(&fwc->work);
1420
1421 fw_fallback_set_cache_timeout();
1422
1423 mutex_lock(&fw_lock);
1424 fwc->state = FW_LOADER_START_CACHE;
1425 dpm_for_each_dev(NULL, dev_cache_fw_image);
1426 mutex_unlock(&fw_lock);
1427
1428 /* wait for completion of caching firmware for all devices */
1429 async_synchronize_full_domain(&fw_cache_domain);
1430
1431 fw_fallback_set_default_timeout();
1432}
1433
1434/**
1435 * device_uncache_fw_images() - uncache devices' firmware
1436 *
1437 * uncache all firmwares which have been cached successfully
1438 * by device_uncache_fw_images earlier
1439 */
1440static void device_uncache_fw_images(void)
1441{
1442 pr_debug("%s\n", __func__);
1443 __device_uncache_fw_images();
1444}
1445
1446static void device_uncache_fw_images_work(struct work_struct *work)
1447{
1448 device_uncache_fw_images();
1449}
1450
1451/**
1452 * device_uncache_fw_images_delay() - uncache devices firmwares
1453 * @delay: number of milliseconds to delay uncache device firmwares
1454 *
1455 * uncache all devices's firmwares which has been cached successfully
1456 * by device_cache_fw_images after @delay milliseconds.
1457 */
1458static void device_uncache_fw_images_delay(unsigned long delay)
1459{
1460 queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1461 msecs_to_jiffies(delay));
1462}
1463
1464static int fw_pm_notify(struct notifier_block *notify_block,
1465 unsigned long mode, void *unused)
1466{
1467 switch (mode) {
1468 case PM_HIBERNATION_PREPARE:
1469 case PM_SUSPEND_PREPARE:
1470 case PM_RESTORE_PREPARE:
1471 /*
1472 * kill pending fallback requests with a custom fallback
1473 * to avoid stalling suspend.
1474 */
1475 kill_pending_fw_fallback_reqs(true);
1476 device_cache_fw_images();
1477 break;
1478
1479 case PM_POST_SUSPEND:
1480 case PM_POST_HIBERNATION:
1481 case PM_POST_RESTORE:
1482 /*
1483 * In case that system sleep failed and syscore_suspend is
1484 * not called.
1485 */
1486 mutex_lock(&fw_lock);
1487 fw_cache.state = FW_LOADER_NO_CACHE;
1488 mutex_unlock(&fw_lock);
1489
1490 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1491 break;
1492 }
1493
1494 return 0;
1495}
1496
1497/* stop caching firmware once syscore_suspend is reached */
1498static int fw_suspend(void)
1499{
1500 fw_cache.state = FW_LOADER_NO_CACHE;
1501 return 0;
1502}
1503
1504static struct syscore_ops fw_syscore_ops = {
1505 .suspend = fw_suspend,
1506};
1507
1508static int __init register_fw_pm_ops(void)
1509{
1510 int ret;
1511
1512 spin_lock_init(&fw_cache.name_lock);
1513 INIT_LIST_HEAD(&fw_cache.fw_names);
1514
1515 INIT_DELAYED_WORK(&fw_cache.work,
1516 device_uncache_fw_images_work);
1517
1518 fw_cache.pm_notify.notifier_call = fw_pm_notify;
1519 ret = register_pm_notifier(&fw_cache.pm_notify);
1520 if (ret)
1521 return ret;
1522
1523 register_syscore_ops(&fw_syscore_ops);
1524
1525 return ret;
1526}
1527
1528static inline void unregister_fw_pm_ops(void)
1529{
1530 unregister_syscore_ops(&fw_syscore_ops);
1531 unregister_pm_notifier(&fw_cache.pm_notify);
1532}
1533#else
1534static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv)
1535{
1536}
1537static inline int register_fw_pm_ops(void)
1538{
1539 return 0;
1540}
1541static inline void unregister_fw_pm_ops(void)
1542{
1543}
1544#endif
1545
1546static void __init fw_cache_init(void)
1547{
1548 spin_lock_init(&fw_cache.lock);
1549 INIT_LIST_HEAD(&fw_cache.head);
1550 fw_cache.state = FW_LOADER_NO_CACHE;
1551}
1552
1553static int fw_shutdown_notify(struct notifier_block *unused1,
1554 unsigned long unused2, void *unused3)
1555{
1556 /*
1557 * Kill all pending fallback requests to avoid both stalling shutdown,
1558 * and avoid a deadlock with the usermode_lock.
1559 */
1560 kill_pending_fw_fallback_reqs(false);
1561
1562 return NOTIFY_DONE;
1563}
1564
1565static struct notifier_block fw_shutdown_nb = {
1566 .notifier_call = fw_shutdown_notify,
1567};
1568
1569static int __init firmware_class_init(void)
1570{
1571 int ret;
1572
1573 /* No need to unfold these on exit */
1574 fw_cache_init();
1575
1576 ret = register_fw_pm_ops();
1577 if (ret)
1578 return ret;
1579
1580 ret = register_reboot_notifier(&fw_shutdown_nb);
1581 if (ret)
1582 goto out;
1583
1584 return register_sysfs_loader();
1585
1586out:
1587 unregister_fw_pm_ops();
1588 return ret;
1589}
1590
1591static void __exit firmware_class_exit(void)
1592{
1593 unregister_fw_pm_ops();
1594 unregister_reboot_notifier(&fw_shutdown_nb);
1595 unregister_sysfs_loader();
1596}
1597
1598fs_initcall(firmware_class_init);
1599module_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#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_PM_SLEEP
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, enum fw_opt 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 fw_free_paged_buf(fw_priv); /* free leftover pages */
256 if (!fw_priv->allocated_size)
257 vfree(fw_priv->data);
258 kfree_const(fw_priv->fw_name);
259 kfree(fw_priv);
260}
261
262static void free_fw_priv(struct fw_priv *fw_priv)
263{
264 struct firmware_cache *fwc = fw_priv->fwc;
265 spin_lock(&fwc->lock);
266 if (!kref_put(&fw_priv->ref, __free_fw_priv))
267 spin_unlock(&fwc->lock);
268}
269
270#ifdef CONFIG_FW_LOADER_PAGED_BUF
271void fw_free_paged_buf(struct fw_priv *fw_priv)
272{
273 int i;
274
275 if (!fw_priv->pages)
276 return;
277
278 for (i = 0; i < fw_priv->nr_pages; i++)
279 __free_page(fw_priv->pages[i]);
280 kvfree(fw_priv->pages);
281 fw_priv->pages = NULL;
282 fw_priv->page_array_size = 0;
283 fw_priv->nr_pages = 0;
284}
285
286int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed)
287{
288 /* If the array of pages is too small, grow it */
289 if (fw_priv->page_array_size < pages_needed) {
290 int new_array_size = max(pages_needed,
291 fw_priv->page_array_size * 2);
292 struct page **new_pages;
293
294 new_pages = kvmalloc_array(new_array_size, sizeof(void *),
295 GFP_KERNEL);
296 if (!new_pages)
297 return -ENOMEM;
298 memcpy(new_pages, fw_priv->pages,
299 fw_priv->page_array_size * sizeof(void *));
300 memset(&new_pages[fw_priv->page_array_size], 0, sizeof(void *) *
301 (new_array_size - fw_priv->page_array_size));
302 kvfree(fw_priv->pages);
303 fw_priv->pages = new_pages;
304 fw_priv->page_array_size = new_array_size;
305 }
306
307 while (fw_priv->nr_pages < pages_needed) {
308 fw_priv->pages[fw_priv->nr_pages] =
309 alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
310
311 if (!fw_priv->pages[fw_priv->nr_pages])
312 return -ENOMEM;
313 fw_priv->nr_pages++;
314 }
315
316 return 0;
317}
318
319int fw_map_paged_buf(struct fw_priv *fw_priv)
320{
321 /* one pages buffer should be mapped/unmapped only once */
322 if (!fw_priv->pages)
323 return 0;
324
325 vunmap(fw_priv->data);
326 fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages, 0,
327 PAGE_KERNEL_RO);
328 if (!fw_priv->data)
329 return -ENOMEM;
330
331 /* page table is no longer needed after mapping, let's free */
332 kvfree(fw_priv->pages);
333 fw_priv->pages = NULL;
334
335 return 0;
336}
337#endif
338
339/*
340 * XZ-compressed firmware support
341 */
342#ifdef CONFIG_FW_LOADER_COMPRESS
343/* show an error and return the standard error code */
344static int fw_decompress_xz_error(struct device *dev, enum xz_ret xz_ret)
345{
346 if (xz_ret != XZ_STREAM_END) {
347 dev_warn(dev, "xz decompression failed (xz_ret=%d)\n", xz_ret);
348 return xz_ret == XZ_MEM_ERROR ? -ENOMEM : -EINVAL;
349 }
350 return 0;
351}
352
353/* single-shot decompression onto the pre-allocated buffer */
354static int fw_decompress_xz_single(struct device *dev, struct fw_priv *fw_priv,
355 size_t in_size, const void *in_buffer)
356{
357 struct xz_dec *xz_dec;
358 struct xz_buf xz_buf;
359 enum xz_ret xz_ret;
360
361 xz_dec = xz_dec_init(XZ_SINGLE, (u32)-1);
362 if (!xz_dec)
363 return -ENOMEM;
364
365 xz_buf.in_size = in_size;
366 xz_buf.in = in_buffer;
367 xz_buf.in_pos = 0;
368 xz_buf.out_size = fw_priv->allocated_size;
369 xz_buf.out = fw_priv->data;
370 xz_buf.out_pos = 0;
371
372 xz_ret = xz_dec_run(xz_dec, &xz_buf);
373 xz_dec_end(xz_dec);
374
375 fw_priv->size = xz_buf.out_pos;
376 return fw_decompress_xz_error(dev, xz_ret);
377}
378
379/* decompression on paged buffer and map it */
380static int fw_decompress_xz_pages(struct device *dev, struct fw_priv *fw_priv,
381 size_t in_size, const void *in_buffer)
382{
383 struct xz_dec *xz_dec;
384 struct xz_buf xz_buf;
385 enum xz_ret xz_ret;
386 struct page *page;
387 int err = 0;
388
389 xz_dec = xz_dec_init(XZ_DYNALLOC, (u32)-1);
390 if (!xz_dec)
391 return -ENOMEM;
392
393 xz_buf.in_size = in_size;
394 xz_buf.in = in_buffer;
395 xz_buf.in_pos = 0;
396
397 fw_priv->is_paged_buf = true;
398 fw_priv->size = 0;
399 do {
400 if (fw_grow_paged_buf(fw_priv, fw_priv->nr_pages + 1)) {
401 err = -ENOMEM;
402 goto out;
403 }
404
405 /* decompress onto the new allocated page */
406 page = fw_priv->pages[fw_priv->nr_pages - 1];
407 xz_buf.out = kmap(page);
408 xz_buf.out_pos = 0;
409 xz_buf.out_size = PAGE_SIZE;
410 xz_ret = xz_dec_run(xz_dec, &xz_buf);
411 kunmap(page);
412 fw_priv->size += xz_buf.out_pos;
413 /* partial decompression means either end or error */
414 if (xz_buf.out_pos != PAGE_SIZE)
415 break;
416 } while (xz_ret == XZ_OK);
417
418 err = fw_decompress_xz_error(dev, xz_ret);
419 if (!err)
420 err = fw_map_paged_buf(fw_priv);
421
422 out:
423 xz_dec_end(xz_dec);
424 return err;
425}
426
427static int fw_decompress_xz(struct device *dev, struct fw_priv *fw_priv,
428 size_t in_size, const void *in_buffer)
429{
430 /* if the buffer is pre-allocated, we can perform in single-shot mode */
431 if (fw_priv->data)
432 return fw_decompress_xz_single(dev, fw_priv, in_size, in_buffer);
433 else
434 return fw_decompress_xz_pages(dev, fw_priv, in_size, in_buffer);
435}
436#endif /* CONFIG_FW_LOADER_COMPRESS */
437
438/* direct firmware loading support */
439static char fw_path_para[256];
440static const char * const fw_path[] = {
441 fw_path_para,
442 "/lib/firmware/updates/" UTS_RELEASE,
443 "/lib/firmware/updates",
444 "/lib/firmware/" UTS_RELEASE,
445 "/lib/firmware"
446};
447
448/*
449 * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
450 * from kernel command line because firmware_class is generally built in
451 * kernel instead of module.
452 */
453module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
454MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
455
456static int
457fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv,
458 const char *suffix,
459 int (*decompress)(struct device *dev,
460 struct fw_priv *fw_priv,
461 size_t in_size,
462 const void *in_buffer))
463{
464 loff_t size;
465 int i, len;
466 int rc = -ENOENT;
467 char *path;
468 enum kernel_read_file_id id = READING_FIRMWARE;
469 size_t msize = INT_MAX;
470 void *buffer = NULL;
471
472 /* Already populated data member means we're loading into a buffer */
473 if (!decompress && fw_priv->data) {
474 buffer = fw_priv->data;
475 id = READING_FIRMWARE_PREALLOC_BUFFER;
476 msize = fw_priv->allocated_size;
477 }
478
479 path = __getname();
480 if (!path)
481 return -ENOMEM;
482
483 for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
484 /* skip the unset customized path */
485 if (!fw_path[i][0])
486 continue;
487
488 len = snprintf(path, PATH_MAX, "%s/%s%s",
489 fw_path[i], fw_priv->fw_name, suffix);
490 if (len >= PATH_MAX) {
491 rc = -ENAMETOOLONG;
492 break;
493 }
494
495 fw_priv->size = 0;
496 rc = kernel_read_file_from_path(path, &buffer, &size,
497 msize, id);
498 if (rc) {
499 if (rc != -ENOENT)
500 dev_warn(device, "loading %s failed with error %d\n",
501 path, rc);
502 else
503 dev_dbg(device, "loading %s failed for no such file or directory.\n",
504 path);
505 continue;
506 }
507 if (decompress) {
508 dev_dbg(device, "f/w decompressing %s\n",
509 fw_priv->fw_name);
510 rc = decompress(device, fw_priv, size, buffer);
511 /* discard the superfluous original content */
512 vfree(buffer);
513 buffer = NULL;
514 if (rc) {
515 fw_free_paged_buf(fw_priv);
516 continue;
517 }
518 } else {
519 dev_dbg(device, "direct-loading %s\n",
520 fw_priv->fw_name);
521 if (!fw_priv->data)
522 fw_priv->data = buffer;
523 fw_priv->size = size;
524 }
525 fw_state_done(fw_priv);
526 break;
527 }
528 __putname(path);
529
530 return rc;
531}
532
533/* firmware holds the ownership of pages */
534static void firmware_free_data(const struct firmware *fw)
535{
536 /* Loaded directly? */
537 if (!fw->priv) {
538 vfree(fw->data);
539 return;
540 }
541 free_fw_priv(fw->priv);
542}
543
544/* store the pages buffer info firmware from buf */
545static void fw_set_page_data(struct fw_priv *fw_priv, struct firmware *fw)
546{
547 fw->priv = fw_priv;
548#ifdef CONFIG_FW_LOADER_USER_HELPER
549 fw->pages = fw_priv->pages;
550#endif
551 fw->size = fw_priv->size;
552 fw->data = fw_priv->data;
553
554 pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
555 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
556 (unsigned int)fw_priv->size);
557}
558
559#ifdef CONFIG_PM_SLEEP
560static void fw_name_devm_release(struct device *dev, void *res)
561{
562 struct fw_name_devm *fwn = res;
563
564 if (fwn->magic == (unsigned long)&fw_cache)
565 pr_debug("%s: fw_name-%s devm-%p released\n",
566 __func__, fwn->name, res);
567 kfree_const(fwn->name);
568}
569
570static int fw_devm_match(struct device *dev, void *res,
571 void *match_data)
572{
573 struct fw_name_devm *fwn = res;
574
575 return (fwn->magic == (unsigned long)&fw_cache) &&
576 !strcmp(fwn->name, match_data);
577}
578
579static struct fw_name_devm *fw_find_devm_name(struct device *dev,
580 const char *name)
581{
582 struct fw_name_devm *fwn;
583
584 fwn = devres_find(dev, fw_name_devm_release,
585 fw_devm_match, (void *)name);
586 return fwn;
587}
588
589static bool fw_cache_is_setup(struct device *dev, const char *name)
590{
591 struct fw_name_devm *fwn;
592
593 fwn = fw_find_devm_name(dev, name);
594 if (fwn)
595 return true;
596
597 return false;
598}
599
600/* add firmware name into devres list */
601static int fw_add_devm_name(struct device *dev, const char *name)
602{
603 struct fw_name_devm *fwn;
604
605 if (fw_cache_is_setup(dev, name))
606 return 0;
607
608 fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm),
609 GFP_KERNEL);
610 if (!fwn)
611 return -ENOMEM;
612 fwn->name = kstrdup_const(name, GFP_KERNEL);
613 if (!fwn->name) {
614 devres_free(fwn);
615 return -ENOMEM;
616 }
617
618 fwn->magic = (unsigned long)&fw_cache;
619 devres_add(dev, fwn);
620
621 return 0;
622}
623#else
624static bool fw_cache_is_setup(struct device *dev, const char *name)
625{
626 return false;
627}
628
629static int fw_add_devm_name(struct device *dev, const char *name)
630{
631 return 0;
632}
633#endif
634
635int assign_fw(struct firmware *fw, struct device *device,
636 enum fw_opt opt_flags)
637{
638 struct fw_priv *fw_priv = fw->priv;
639 int ret;
640
641 mutex_lock(&fw_lock);
642 if (!fw_priv->size || fw_state_is_aborted(fw_priv)) {
643 mutex_unlock(&fw_lock);
644 return -ENOENT;
645 }
646
647 /*
648 * add firmware name into devres list so that we can auto cache
649 * and uncache firmware for device.
650 *
651 * device may has been deleted already, but the problem
652 * should be fixed in devres or driver core.
653 */
654 /* don't cache firmware handled without uevent */
655 if (device && (opt_flags & FW_OPT_UEVENT) &&
656 !(opt_flags & FW_OPT_NOCACHE)) {
657 ret = fw_add_devm_name(device, fw_priv->fw_name);
658 if (ret) {
659 mutex_unlock(&fw_lock);
660 return ret;
661 }
662 }
663
664 /*
665 * After caching firmware image is started, let it piggyback
666 * on request firmware.
667 */
668 if (!(opt_flags & FW_OPT_NOCACHE) &&
669 fw_priv->fwc->state == FW_LOADER_START_CACHE) {
670 if (fw_cache_piggyback_on_request(fw_priv->fw_name))
671 kref_get(&fw_priv->ref);
672 }
673
674 /* pass the pages buffer to driver at the last minute */
675 fw_set_page_data(fw_priv, fw);
676 mutex_unlock(&fw_lock);
677 return 0;
678}
679
680/* prepare firmware and firmware_buf structs;
681 * return 0 if a firmware is already assigned, 1 if need to load one,
682 * or a negative error code
683 */
684static int
685_request_firmware_prepare(struct firmware **firmware_p, const char *name,
686 struct device *device, void *dbuf, size_t size,
687 enum fw_opt opt_flags)
688{
689 struct firmware *firmware;
690 struct fw_priv *fw_priv;
691 int ret;
692
693 *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
694 if (!firmware) {
695 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
696 __func__);
697 return -ENOMEM;
698 }
699
700 if (fw_get_builtin_firmware(firmware, name, dbuf, size)) {
701 dev_dbg(device, "using built-in %s\n", name);
702 return 0; /* assigned */
703 }
704
705 ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv, dbuf, size,
706 opt_flags);
707
708 /*
709 * bind with 'priv' now to avoid warning in failure path
710 * of requesting firmware.
711 */
712 firmware->priv = fw_priv;
713
714 if (ret > 0) {
715 ret = fw_state_wait(fw_priv);
716 if (!ret) {
717 fw_set_page_data(fw_priv, firmware);
718 return 0; /* assigned */
719 }
720 }
721
722 if (ret < 0)
723 return ret;
724 return 1; /* need to load */
725}
726
727/*
728 * Batched requests need only one wake, we need to do this step last due to the
729 * fallback mechanism. The buf is protected with kref_get(), and it won't be
730 * released until the last user calls release_firmware().
731 *
732 * Failed batched requests are possible as well, in such cases we just share
733 * the struct fw_priv and won't release it until all requests are woken
734 * and have gone through this same path.
735 */
736static void fw_abort_batch_reqs(struct firmware *fw)
737{
738 struct fw_priv *fw_priv;
739
740 /* Loaded directly? */
741 if (!fw || !fw->priv)
742 return;
743
744 fw_priv = fw->priv;
745 if (!fw_state_is_aborted(fw_priv))
746 fw_state_aborted(fw_priv);
747}
748
749/* called from request_firmware() and request_firmware_work_func() */
750static int
751_request_firmware(const struct firmware **firmware_p, const char *name,
752 struct device *device, void *buf, size_t size,
753 enum fw_opt opt_flags)
754{
755 struct firmware *fw = NULL;
756 int ret;
757
758 if (!firmware_p)
759 return -EINVAL;
760
761 if (!name || name[0] == '\0') {
762 ret = -EINVAL;
763 goto out;
764 }
765
766 ret = _request_firmware_prepare(&fw, name, device, buf, size,
767 opt_flags);
768 if (ret <= 0) /* error or already assigned */
769 goto out;
770
771 ret = fw_get_filesystem_firmware(device, fw->priv, "", NULL);
772#ifdef CONFIG_FW_LOADER_COMPRESS
773 if (ret == -ENOENT)
774 ret = fw_get_filesystem_firmware(device, fw->priv, ".xz",
775 fw_decompress_xz);
776#endif
777
778 if (ret) {
779 if (!(opt_flags & FW_OPT_NO_WARN))
780 dev_warn(device,
781 "Direct firmware load for %s failed with error %d\n",
782 name, ret);
783 ret = firmware_fallback_sysfs(fw, name, device, opt_flags, ret);
784 } else
785 ret = assign_fw(fw, device, opt_flags);
786
787 out:
788 if (ret < 0) {
789 fw_abort_batch_reqs(fw);
790 release_firmware(fw);
791 fw = NULL;
792 }
793
794 *firmware_p = fw;
795 return ret;
796}
797
798/**
799 * request_firmware() - send firmware request and wait for it
800 * @firmware_p: pointer to firmware image
801 * @name: name of firmware file
802 * @device: device for which firmware is being loaded
803 *
804 * @firmware_p will be used to return a firmware image by the name
805 * of @name for device @device.
806 *
807 * Should be called from user context where sleeping is allowed.
808 *
809 * @name will be used as $FIRMWARE in the uevent environment and
810 * should be distinctive enough not to be confused with any other
811 * firmware image for this or any other device.
812 *
813 * Caller must hold the reference count of @device.
814 *
815 * The function can be called safely inside device's suspend and
816 * resume callback.
817 **/
818int
819request_firmware(const struct firmware **firmware_p, const char *name,
820 struct device *device)
821{
822 int ret;
823
824 /* Need to pin this module until return */
825 __module_get(THIS_MODULE);
826 ret = _request_firmware(firmware_p, name, device, NULL, 0,
827 FW_OPT_UEVENT);
828 module_put(THIS_MODULE);
829 return ret;
830}
831EXPORT_SYMBOL(request_firmware);
832
833/**
834 * firmware_request_nowarn() - request for an optional fw module
835 * @firmware: pointer to firmware image
836 * @name: name of firmware file
837 * @device: device for which firmware is being loaded
838 *
839 * This function is similar in behaviour to request_firmware(), except
840 * it doesn't produce warning messages when the file is not found.
841 * The sysfs fallback mechanism is enabled if direct filesystem lookup fails,
842 * however, however failures to find the firmware file with it are still
843 * suppressed. It is therefore up to the driver to check for the return value
844 * of this call and to decide when to inform the users of errors.
845 **/
846int firmware_request_nowarn(const struct firmware **firmware, const char *name,
847 struct device *device)
848{
849 int ret;
850
851 /* Need to pin this module until return */
852 __module_get(THIS_MODULE);
853 ret = _request_firmware(firmware, name, device, NULL, 0,
854 FW_OPT_UEVENT | FW_OPT_NO_WARN);
855 module_put(THIS_MODULE);
856 return ret;
857}
858EXPORT_SYMBOL_GPL(firmware_request_nowarn);
859
860/**
861 * request_firmware_direct() - load firmware directly without usermode helper
862 * @firmware_p: pointer to firmware image
863 * @name: name of firmware file
864 * @device: device for which firmware is being loaded
865 *
866 * This function works pretty much like request_firmware(), but this doesn't
867 * fall back to usermode helper even if the firmware couldn't be loaded
868 * directly from fs. Hence it's useful for loading optional firmwares, which
869 * aren't always present, without extra long timeouts of udev.
870 **/
871int request_firmware_direct(const struct firmware **firmware_p,
872 const char *name, struct device *device)
873{
874 int ret;
875
876 __module_get(THIS_MODULE);
877 ret = _request_firmware(firmware_p, name, device, NULL, 0,
878 FW_OPT_UEVENT | FW_OPT_NO_WARN |
879 FW_OPT_NOFALLBACK);
880 module_put(THIS_MODULE);
881 return ret;
882}
883EXPORT_SYMBOL_GPL(request_firmware_direct);
884
885/**
886 * firmware_request_cache() - cache firmware for suspend so resume can use it
887 * @name: name of firmware file
888 * @device: device for which firmware should be cached for
889 *
890 * There are some devices with an optimization that enables the device to not
891 * require loading firmware on system reboot. This optimization may still
892 * require the firmware present on resume from suspend. This routine can be
893 * used to ensure the firmware is present on resume from suspend in these
894 * situations. This helper is not compatible with drivers which use
895 * request_firmware_into_buf() or request_firmware_nowait() with no uevent set.
896 **/
897int firmware_request_cache(struct device *device, const char *name)
898{
899 int ret;
900
901 mutex_lock(&fw_lock);
902 ret = fw_add_devm_name(device, name);
903 mutex_unlock(&fw_lock);
904
905 return ret;
906}
907EXPORT_SYMBOL_GPL(firmware_request_cache);
908
909/**
910 * request_firmware_into_buf() - load firmware into a previously allocated buffer
911 * @firmware_p: pointer to firmware image
912 * @name: name of firmware file
913 * @device: device for which firmware is being loaded and DMA region allocated
914 * @buf: address of buffer to load firmware into
915 * @size: size of buffer
916 *
917 * This function works pretty much like request_firmware(), but it doesn't
918 * allocate a buffer to hold the firmware data. Instead, the firmware
919 * is loaded directly into the buffer pointed to by @buf and the @firmware_p
920 * data member is pointed at @buf.
921 *
922 * This function doesn't cache firmware either.
923 */
924int
925request_firmware_into_buf(const struct firmware **firmware_p, const char *name,
926 struct device *device, void *buf, size_t size)
927{
928 int ret;
929
930 if (fw_cache_is_setup(device, name))
931 return -EOPNOTSUPP;
932
933 __module_get(THIS_MODULE);
934 ret = _request_firmware(firmware_p, name, device, buf, size,
935 FW_OPT_UEVENT | FW_OPT_NOCACHE);
936 module_put(THIS_MODULE);
937 return ret;
938}
939EXPORT_SYMBOL(request_firmware_into_buf);
940
941/**
942 * release_firmware() - release the resource associated with a firmware image
943 * @fw: firmware resource to release
944 **/
945void release_firmware(const struct firmware *fw)
946{
947 if (fw) {
948 if (!fw_is_builtin_firmware(fw))
949 firmware_free_data(fw);
950 kfree(fw);
951 }
952}
953EXPORT_SYMBOL(release_firmware);
954
955/* Async support */
956struct firmware_work {
957 struct work_struct work;
958 struct module *module;
959 const char *name;
960 struct device *device;
961 void *context;
962 void (*cont)(const struct firmware *fw, void *context);
963 enum fw_opt opt_flags;
964};
965
966static void request_firmware_work_func(struct work_struct *work)
967{
968 struct firmware_work *fw_work;
969 const struct firmware *fw;
970
971 fw_work = container_of(work, struct firmware_work, work);
972
973 _request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0,
974 fw_work->opt_flags);
975 fw_work->cont(fw, fw_work->context);
976 put_device(fw_work->device); /* taken in request_firmware_nowait() */
977
978 module_put(fw_work->module);
979 kfree_const(fw_work->name);
980 kfree(fw_work);
981}
982
983/**
984 * request_firmware_nowait() - asynchronous version of request_firmware
985 * @module: module requesting the firmware
986 * @uevent: sends uevent to copy the firmware image if this flag
987 * is non-zero else the firmware copy must be done manually.
988 * @name: name of firmware file
989 * @device: device for which firmware is being loaded
990 * @gfp: allocation flags
991 * @context: will be passed over to @cont, and
992 * @fw may be %NULL if firmware request fails.
993 * @cont: function will be called asynchronously when the firmware
994 * request is over.
995 *
996 * Caller must hold the reference count of @device.
997 *
998 * Asynchronous variant of request_firmware() for user contexts:
999 * - sleep for as small periods as possible since it may
1000 * increase kernel boot time of built-in device drivers
1001 * requesting firmware in their ->probe() methods, if
1002 * @gfp is GFP_KERNEL.
1003 *
1004 * - can't sleep at all if @gfp is GFP_ATOMIC.
1005 **/
1006int
1007request_firmware_nowait(
1008 struct module *module, bool uevent,
1009 const char *name, struct device *device, gfp_t gfp, void *context,
1010 void (*cont)(const struct firmware *fw, void *context))
1011{
1012 struct firmware_work *fw_work;
1013
1014 fw_work = kzalloc(sizeof(struct firmware_work), gfp);
1015 if (!fw_work)
1016 return -ENOMEM;
1017
1018 fw_work->module = module;
1019 fw_work->name = kstrdup_const(name, gfp);
1020 if (!fw_work->name) {
1021 kfree(fw_work);
1022 return -ENOMEM;
1023 }
1024 fw_work->device = device;
1025 fw_work->context = context;
1026 fw_work->cont = cont;
1027 fw_work->opt_flags = FW_OPT_NOWAIT |
1028 (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
1029
1030 if (!uevent && fw_cache_is_setup(device, name)) {
1031 kfree_const(fw_work->name);
1032 kfree(fw_work);
1033 return -EOPNOTSUPP;
1034 }
1035
1036 if (!try_module_get(module)) {
1037 kfree_const(fw_work->name);
1038 kfree(fw_work);
1039 return -EFAULT;
1040 }
1041
1042 get_device(fw_work->device);
1043 INIT_WORK(&fw_work->work, request_firmware_work_func);
1044 schedule_work(&fw_work->work);
1045 return 0;
1046}
1047EXPORT_SYMBOL(request_firmware_nowait);
1048
1049#ifdef CONFIG_PM_SLEEP
1050static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1051
1052/**
1053 * cache_firmware() - cache one firmware image in kernel memory space
1054 * @fw_name: the firmware image name
1055 *
1056 * Cache firmware in kernel memory so that drivers can use it when
1057 * system isn't ready for them to request firmware image from userspace.
1058 * Once it returns successfully, driver can use request_firmware or its
1059 * nowait version to get the cached firmware without any interacting
1060 * with userspace
1061 *
1062 * Return 0 if the firmware image has been cached successfully
1063 * Return !0 otherwise
1064 *
1065 */
1066static int cache_firmware(const char *fw_name)
1067{
1068 int ret;
1069 const struct firmware *fw;
1070
1071 pr_debug("%s: %s\n", __func__, fw_name);
1072
1073 ret = request_firmware(&fw, fw_name, NULL);
1074 if (!ret)
1075 kfree(fw);
1076
1077 pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1078
1079 return ret;
1080}
1081
1082static struct fw_priv *lookup_fw_priv(const char *fw_name)
1083{
1084 struct fw_priv *tmp;
1085 struct firmware_cache *fwc = &fw_cache;
1086
1087 spin_lock(&fwc->lock);
1088 tmp = __lookup_fw_priv(fw_name);
1089 spin_unlock(&fwc->lock);
1090
1091 return tmp;
1092}
1093
1094/**
1095 * uncache_firmware() - remove one cached firmware image
1096 * @fw_name: the firmware image name
1097 *
1098 * Uncache one firmware image which has been cached successfully
1099 * before.
1100 *
1101 * Return 0 if the firmware cache has been removed successfully
1102 * Return !0 otherwise
1103 *
1104 */
1105static int uncache_firmware(const char *fw_name)
1106{
1107 struct fw_priv *fw_priv;
1108 struct firmware fw;
1109
1110 pr_debug("%s: %s\n", __func__, fw_name);
1111
1112 if (fw_get_builtin_firmware(&fw, fw_name, NULL, 0))
1113 return 0;
1114
1115 fw_priv = lookup_fw_priv(fw_name);
1116 if (fw_priv) {
1117 free_fw_priv(fw_priv);
1118 return 0;
1119 }
1120
1121 return -EINVAL;
1122}
1123
1124static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1125{
1126 struct fw_cache_entry *fce;
1127
1128 fce = kzalloc(sizeof(*fce), GFP_ATOMIC);
1129 if (!fce)
1130 goto exit;
1131
1132 fce->name = kstrdup_const(name, GFP_ATOMIC);
1133 if (!fce->name) {
1134 kfree(fce);
1135 fce = NULL;
1136 goto exit;
1137 }
1138exit:
1139 return fce;
1140}
1141
1142static int __fw_entry_found(const char *name)
1143{
1144 struct firmware_cache *fwc = &fw_cache;
1145 struct fw_cache_entry *fce;
1146
1147 list_for_each_entry(fce, &fwc->fw_names, list) {
1148 if (!strcmp(fce->name, name))
1149 return 1;
1150 }
1151 return 0;
1152}
1153
1154static int fw_cache_piggyback_on_request(const char *name)
1155{
1156 struct firmware_cache *fwc = &fw_cache;
1157 struct fw_cache_entry *fce;
1158 int ret = 0;
1159
1160 spin_lock(&fwc->name_lock);
1161 if (__fw_entry_found(name))
1162 goto found;
1163
1164 fce = alloc_fw_cache_entry(name);
1165 if (fce) {
1166 ret = 1;
1167 list_add(&fce->list, &fwc->fw_names);
1168 pr_debug("%s: fw: %s\n", __func__, name);
1169 }
1170found:
1171 spin_unlock(&fwc->name_lock);
1172 return ret;
1173}
1174
1175static void free_fw_cache_entry(struct fw_cache_entry *fce)
1176{
1177 kfree_const(fce->name);
1178 kfree(fce);
1179}
1180
1181static void __async_dev_cache_fw_image(void *fw_entry,
1182 async_cookie_t cookie)
1183{
1184 struct fw_cache_entry *fce = fw_entry;
1185 struct firmware_cache *fwc = &fw_cache;
1186 int ret;
1187
1188 ret = cache_firmware(fce->name);
1189 if (ret) {
1190 spin_lock(&fwc->name_lock);
1191 list_del(&fce->list);
1192 spin_unlock(&fwc->name_lock);
1193
1194 free_fw_cache_entry(fce);
1195 }
1196}
1197
1198/* called with dev->devres_lock held */
1199static void dev_create_fw_entry(struct device *dev, void *res,
1200 void *data)
1201{
1202 struct fw_name_devm *fwn = res;
1203 const char *fw_name = fwn->name;
1204 struct list_head *head = data;
1205 struct fw_cache_entry *fce;
1206
1207 fce = alloc_fw_cache_entry(fw_name);
1208 if (fce)
1209 list_add(&fce->list, head);
1210}
1211
1212static int devm_name_match(struct device *dev, void *res,
1213 void *match_data)
1214{
1215 struct fw_name_devm *fwn = res;
1216 return (fwn->magic == (unsigned long)match_data);
1217}
1218
1219static void dev_cache_fw_image(struct device *dev, void *data)
1220{
1221 LIST_HEAD(todo);
1222 struct fw_cache_entry *fce;
1223 struct fw_cache_entry *fce_next;
1224 struct firmware_cache *fwc = &fw_cache;
1225
1226 devres_for_each_res(dev, fw_name_devm_release,
1227 devm_name_match, &fw_cache,
1228 dev_create_fw_entry, &todo);
1229
1230 list_for_each_entry_safe(fce, fce_next, &todo, list) {
1231 list_del(&fce->list);
1232
1233 spin_lock(&fwc->name_lock);
1234 /* only one cache entry for one firmware */
1235 if (!__fw_entry_found(fce->name)) {
1236 list_add(&fce->list, &fwc->fw_names);
1237 } else {
1238 free_fw_cache_entry(fce);
1239 fce = NULL;
1240 }
1241 spin_unlock(&fwc->name_lock);
1242
1243 if (fce)
1244 async_schedule_domain(__async_dev_cache_fw_image,
1245 (void *)fce,
1246 &fw_cache_domain);
1247 }
1248}
1249
1250static void __device_uncache_fw_images(void)
1251{
1252 struct firmware_cache *fwc = &fw_cache;
1253 struct fw_cache_entry *fce;
1254
1255 spin_lock(&fwc->name_lock);
1256 while (!list_empty(&fwc->fw_names)) {
1257 fce = list_entry(fwc->fw_names.next,
1258 struct fw_cache_entry, list);
1259 list_del(&fce->list);
1260 spin_unlock(&fwc->name_lock);
1261
1262 uncache_firmware(fce->name);
1263 free_fw_cache_entry(fce);
1264
1265 spin_lock(&fwc->name_lock);
1266 }
1267 spin_unlock(&fwc->name_lock);
1268}
1269
1270/**
1271 * device_cache_fw_images() - cache devices' firmware
1272 *
1273 * If one device called request_firmware or its nowait version
1274 * successfully before, the firmware names are recored into the
1275 * device's devres link list, so device_cache_fw_images can call
1276 * cache_firmware() to cache these firmwares for the device,
1277 * then the device driver can load its firmwares easily at
1278 * time when system is not ready to complete loading firmware.
1279 */
1280static void device_cache_fw_images(void)
1281{
1282 struct firmware_cache *fwc = &fw_cache;
1283 DEFINE_WAIT(wait);
1284
1285 pr_debug("%s\n", __func__);
1286
1287 /* cancel uncache work */
1288 cancel_delayed_work_sync(&fwc->work);
1289
1290 fw_fallback_set_cache_timeout();
1291
1292 mutex_lock(&fw_lock);
1293 fwc->state = FW_LOADER_START_CACHE;
1294 dpm_for_each_dev(NULL, dev_cache_fw_image);
1295 mutex_unlock(&fw_lock);
1296
1297 /* wait for completion of caching firmware for all devices */
1298 async_synchronize_full_domain(&fw_cache_domain);
1299
1300 fw_fallback_set_default_timeout();
1301}
1302
1303/**
1304 * device_uncache_fw_images() - uncache devices' firmware
1305 *
1306 * uncache all firmwares which have been cached successfully
1307 * by device_uncache_fw_images earlier
1308 */
1309static void device_uncache_fw_images(void)
1310{
1311 pr_debug("%s\n", __func__);
1312 __device_uncache_fw_images();
1313}
1314
1315static void device_uncache_fw_images_work(struct work_struct *work)
1316{
1317 device_uncache_fw_images();
1318}
1319
1320/**
1321 * device_uncache_fw_images_delay() - uncache devices firmwares
1322 * @delay: number of milliseconds to delay uncache device firmwares
1323 *
1324 * uncache all devices's firmwares which has been cached successfully
1325 * by device_cache_fw_images after @delay milliseconds.
1326 */
1327static void device_uncache_fw_images_delay(unsigned long delay)
1328{
1329 queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1330 msecs_to_jiffies(delay));
1331}
1332
1333static int fw_pm_notify(struct notifier_block *notify_block,
1334 unsigned long mode, void *unused)
1335{
1336 switch (mode) {
1337 case PM_HIBERNATION_PREPARE:
1338 case PM_SUSPEND_PREPARE:
1339 case PM_RESTORE_PREPARE:
1340 /*
1341 * kill pending fallback requests with a custom fallback
1342 * to avoid stalling suspend.
1343 */
1344 kill_pending_fw_fallback_reqs(true);
1345 device_cache_fw_images();
1346 break;
1347
1348 case PM_POST_SUSPEND:
1349 case PM_POST_HIBERNATION:
1350 case PM_POST_RESTORE:
1351 /*
1352 * In case that system sleep failed and syscore_suspend is
1353 * not called.
1354 */
1355 mutex_lock(&fw_lock);
1356 fw_cache.state = FW_LOADER_NO_CACHE;
1357 mutex_unlock(&fw_lock);
1358
1359 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1360 break;
1361 }
1362
1363 return 0;
1364}
1365
1366/* stop caching firmware once syscore_suspend is reached */
1367static int fw_suspend(void)
1368{
1369 fw_cache.state = FW_LOADER_NO_CACHE;
1370 return 0;
1371}
1372
1373static struct syscore_ops fw_syscore_ops = {
1374 .suspend = fw_suspend,
1375};
1376
1377static int __init register_fw_pm_ops(void)
1378{
1379 int ret;
1380
1381 spin_lock_init(&fw_cache.name_lock);
1382 INIT_LIST_HEAD(&fw_cache.fw_names);
1383
1384 INIT_DELAYED_WORK(&fw_cache.work,
1385 device_uncache_fw_images_work);
1386
1387 fw_cache.pm_notify.notifier_call = fw_pm_notify;
1388 ret = register_pm_notifier(&fw_cache.pm_notify);
1389 if (ret)
1390 return ret;
1391
1392 register_syscore_ops(&fw_syscore_ops);
1393
1394 return ret;
1395}
1396
1397static inline void unregister_fw_pm_ops(void)
1398{
1399 unregister_syscore_ops(&fw_syscore_ops);
1400 unregister_pm_notifier(&fw_cache.pm_notify);
1401}
1402#else
1403static int fw_cache_piggyback_on_request(const char *name)
1404{
1405 return 0;
1406}
1407static inline int register_fw_pm_ops(void)
1408{
1409 return 0;
1410}
1411static inline void unregister_fw_pm_ops(void)
1412{
1413}
1414#endif
1415
1416static void __init fw_cache_init(void)
1417{
1418 spin_lock_init(&fw_cache.lock);
1419 INIT_LIST_HEAD(&fw_cache.head);
1420 fw_cache.state = FW_LOADER_NO_CACHE;
1421}
1422
1423static int fw_shutdown_notify(struct notifier_block *unused1,
1424 unsigned long unused2, void *unused3)
1425{
1426 /*
1427 * Kill all pending fallback requests to avoid both stalling shutdown,
1428 * and avoid a deadlock with the usermode_lock.
1429 */
1430 kill_pending_fw_fallback_reqs(false);
1431
1432 return NOTIFY_DONE;
1433}
1434
1435static struct notifier_block fw_shutdown_nb = {
1436 .notifier_call = fw_shutdown_notify,
1437};
1438
1439static int __init firmware_class_init(void)
1440{
1441 int ret;
1442
1443 /* No need to unfold these on exit */
1444 fw_cache_init();
1445
1446 ret = register_fw_pm_ops();
1447 if (ret)
1448 return ret;
1449
1450 ret = register_reboot_notifier(&fw_shutdown_nb);
1451 if (ret)
1452 goto out;
1453
1454 return register_sysfs_loader();
1455
1456out:
1457 unregister_fw_pm_ops();
1458 return ret;
1459}
1460
1461static void __exit firmware_class_exit(void)
1462{
1463 unregister_fw_pm_ops();
1464 unregister_reboot_notifier(&fw_shutdown_nb);
1465 unregister_sysfs_loader();
1466}
1467
1468fs_initcall(firmware_class_init);
1469module_exit(firmware_class_exit);