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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;
96bool fw_load_abort_all;
97
98void fw_state_init(struct fw_priv *fw_priv)
99{
100 struct fw_state *fw_st = &fw_priv->fw_st;
101
102 init_completion(&fw_st->completion);
103 fw_st->status = FW_STATUS_UNKNOWN;
104}
105
106static inline int fw_state_wait(struct fw_priv *fw_priv)
107{
108 return __fw_state_wait_common(fw_priv, MAX_SCHEDULE_TIMEOUT);
109}
110
111static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv);
112
113static struct fw_priv *__allocate_fw_priv(const char *fw_name,
114 struct firmware_cache *fwc,
115 void *dbuf,
116 size_t size,
117 size_t offset,
118 u32 opt_flags)
119{
120 struct fw_priv *fw_priv;
121
122 /* For a partial read, the buffer must be preallocated. */
123 if ((opt_flags & FW_OPT_PARTIAL) && !dbuf)
124 return NULL;
125
126 /* Only partial reads are allowed to use an offset. */
127 if (offset != 0 && !(opt_flags & FW_OPT_PARTIAL))
128 return NULL;
129
130 fw_priv = kzalloc(sizeof(*fw_priv), GFP_ATOMIC);
131 if (!fw_priv)
132 return NULL;
133
134 fw_priv->fw_name = kstrdup_const(fw_name, GFP_ATOMIC);
135 if (!fw_priv->fw_name) {
136 kfree(fw_priv);
137 return NULL;
138 }
139
140 kref_init(&fw_priv->ref);
141 fw_priv->fwc = fwc;
142 fw_priv->data = dbuf;
143 fw_priv->allocated_size = size;
144 fw_priv->offset = offset;
145 fw_priv->opt_flags = opt_flags;
146 fw_state_init(fw_priv);
147#ifdef CONFIG_FW_LOADER_USER_HELPER
148 INIT_LIST_HEAD(&fw_priv->pending_list);
149#endif
150
151 pr_debug("%s: fw-%s fw_priv=%p\n", __func__, fw_name, fw_priv);
152
153 return fw_priv;
154}
155
156static struct fw_priv *__lookup_fw_priv(const char *fw_name)
157{
158 struct fw_priv *tmp;
159 struct firmware_cache *fwc = &fw_cache;
160
161 list_for_each_entry(tmp, &fwc->head, list)
162 if (!strcmp(tmp->fw_name, fw_name))
163 return tmp;
164 return NULL;
165}
166
167/* Returns 1 for batching firmware requests with the same name */
168int alloc_lookup_fw_priv(const char *fw_name, struct firmware_cache *fwc,
169 struct fw_priv **fw_priv, void *dbuf, size_t size,
170 size_t offset, u32 opt_flags)
171{
172 struct fw_priv *tmp;
173
174 spin_lock(&fwc->lock);
175 /*
176 * Do not merge requests that are marked to be non-cached or
177 * are performing partial reads.
178 */
179 if (!(opt_flags & (FW_OPT_NOCACHE | FW_OPT_PARTIAL))) {
180 tmp = __lookup_fw_priv(fw_name);
181 if (tmp) {
182 kref_get(&tmp->ref);
183 spin_unlock(&fwc->lock);
184 *fw_priv = tmp;
185 pr_debug("batched request - sharing the same struct fw_priv and lookup for multiple requests\n");
186 return 1;
187 }
188 }
189
190 tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size, offset, opt_flags);
191 if (tmp) {
192 INIT_LIST_HEAD(&tmp->list);
193 if (!(opt_flags & FW_OPT_NOCACHE))
194 list_add(&tmp->list, &fwc->head);
195 }
196 spin_unlock(&fwc->lock);
197
198 *fw_priv = tmp;
199
200 return tmp ? 0 : -ENOMEM;
201}
202
203static void __free_fw_priv(struct kref *ref)
204 __releases(&fwc->lock)
205{
206 struct fw_priv *fw_priv = to_fw_priv(ref);
207 struct firmware_cache *fwc = fw_priv->fwc;
208
209 pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
210 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
211 (unsigned int)fw_priv->size);
212
213 list_del(&fw_priv->list);
214 spin_unlock(&fwc->lock);
215
216 if (fw_is_paged_buf(fw_priv))
217 fw_free_paged_buf(fw_priv);
218 else if (!fw_priv->allocated_size)
219 vfree(fw_priv->data);
220
221 kfree_const(fw_priv->fw_name);
222 kfree(fw_priv);
223}
224
225void free_fw_priv(struct fw_priv *fw_priv)
226{
227 struct firmware_cache *fwc = fw_priv->fwc;
228 spin_lock(&fwc->lock);
229 if (!kref_put(&fw_priv->ref, __free_fw_priv))
230 spin_unlock(&fwc->lock);
231}
232
233#ifdef CONFIG_FW_LOADER_PAGED_BUF
234bool fw_is_paged_buf(struct fw_priv *fw_priv)
235{
236 return fw_priv->is_paged_buf;
237}
238
239void fw_free_paged_buf(struct fw_priv *fw_priv)
240{
241 int i;
242
243 if (!fw_priv->pages)
244 return;
245
246 vunmap(fw_priv->data);
247
248 for (i = 0; i < fw_priv->nr_pages; i++)
249 __free_page(fw_priv->pages[i]);
250 kvfree(fw_priv->pages);
251 fw_priv->pages = NULL;
252 fw_priv->page_array_size = 0;
253 fw_priv->nr_pages = 0;
254 fw_priv->data = NULL;
255 fw_priv->size = 0;
256}
257
258int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed)
259{
260 /* If the array of pages is too small, grow it */
261 if (fw_priv->page_array_size < pages_needed) {
262 int new_array_size = max(pages_needed,
263 fw_priv->page_array_size * 2);
264 struct page **new_pages;
265
266 new_pages = kvmalloc_array(new_array_size, sizeof(void *),
267 GFP_KERNEL);
268 if (!new_pages)
269 return -ENOMEM;
270 memcpy(new_pages, fw_priv->pages,
271 fw_priv->page_array_size * sizeof(void *));
272 memset(&new_pages[fw_priv->page_array_size], 0, sizeof(void *) *
273 (new_array_size - fw_priv->page_array_size));
274 kvfree(fw_priv->pages);
275 fw_priv->pages = new_pages;
276 fw_priv->page_array_size = new_array_size;
277 }
278
279 while (fw_priv->nr_pages < pages_needed) {
280 fw_priv->pages[fw_priv->nr_pages] =
281 alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
282
283 if (!fw_priv->pages[fw_priv->nr_pages])
284 return -ENOMEM;
285 fw_priv->nr_pages++;
286 }
287
288 return 0;
289}
290
291int fw_map_paged_buf(struct fw_priv *fw_priv)
292{
293 /* one pages buffer should be mapped/unmapped only once */
294 if (!fw_priv->pages)
295 return 0;
296
297 vunmap(fw_priv->data);
298 fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages, 0,
299 PAGE_KERNEL_RO);
300 if (!fw_priv->data)
301 return -ENOMEM;
302
303 return 0;
304}
305#endif
306
307/*
308 * ZSTD-compressed firmware support
309 */
310#ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD
311static int fw_decompress_zstd(struct device *dev, struct fw_priv *fw_priv,
312 size_t in_size, const void *in_buffer)
313{
314 size_t len, out_size, workspace_size;
315 void *workspace, *out_buf;
316 zstd_dctx *ctx;
317 int err;
318
319 if (fw_priv->allocated_size) {
320 out_size = fw_priv->allocated_size;
321 out_buf = fw_priv->data;
322 } else {
323 zstd_frame_header params;
324
325 if (zstd_get_frame_header(¶ms, in_buffer, in_size) ||
326 params.frameContentSize == ZSTD_CONTENTSIZE_UNKNOWN) {
327 dev_dbg(dev, "%s: invalid zstd header\n", __func__);
328 return -EINVAL;
329 }
330 out_size = params.frameContentSize;
331 out_buf = vzalloc(out_size);
332 if (!out_buf)
333 return -ENOMEM;
334 }
335
336 workspace_size = zstd_dctx_workspace_bound();
337 workspace = kvzalloc(workspace_size, GFP_KERNEL);
338 if (!workspace) {
339 err = -ENOMEM;
340 goto error;
341 }
342
343 ctx = zstd_init_dctx(workspace, workspace_size);
344 if (!ctx) {
345 dev_dbg(dev, "%s: failed to initialize context\n", __func__);
346 err = -EINVAL;
347 goto error;
348 }
349
350 len = zstd_decompress_dctx(ctx, out_buf, out_size, in_buffer, in_size);
351 if (zstd_is_error(len)) {
352 dev_dbg(dev, "%s: failed to decompress: %d\n", __func__,
353 zstd_get_error_code(len));
354 err = -EINVAL;
355 goto error;
356 }
357
358 if (!fw_priv->allocated_size)
359 fw_priv->data = out_buf;
360 fw_priv->size = len;
361 err = 0;
362
363 error:
364 kvfree(workspace);
365 if (err && !fw_priv->allocated_size)
366 vfree(out_buf);
367 return err;
368}
369#endif /* CONFIG_FW_LOADER_COMPRESS_ZSTD */
370
371/*
372 * XZ-compressed firmware support
373 */
374#ifdef CONFIG_FW_LOADER_COMPRESS_XZ
375/* show an error and return the standard error code */
376static int fw_decompress_xz_error(struct device *dev, enum xz_ret xz_ret)
377{
378 if (xz_ret != XZ_STREAM_END) {
379 dev_warn(dev, "xz decompression failed (xz_ret=%d)\n", xz_ret);
380 return xz_ret == XZ_MEM_ERROR ? -ENOMEM : -EINVAL;
381 }
382 return 0;
383}
384
385/* single-shot decompression onto the pre-allocated buffer */
386static int fw_decompress_xz_single(struct device *dev, struct fw_priv *fw_priv,
387 size_t in_size, const void *in_buffer)
388{
389 struct xz_dec *xz_dec;
390 struct xz_buf xz_buf;
391 enum xz_ret xz_ret;
392
393 xz_dec = xz_dec_init(XZ_SINGLE, (u32)-1);
394 if (!xz_dec)
395 return -ENOMEM;
396
397 xz_buf.in_size = in_size;
398 xz_buf.in = in_buffer;
399 xz_buf.in_pos = 0;
400 xz_buf.out_size = fw_priv->allocated_size;
401 xz_buf.out = fw_priv->data;
402 xz_buf.out_pos = 0;
403
404 xz_ret = xz_dec_run(xz_dec, &xz_buf);
405 xz_dec_end(xz_dec);
406
407 fw_priv->size = xz_buf.out_pos;
408 return fw_decompress_xz_error(dev, xz_ret);
409}
410
411/* decompression on paged buffer and map it */
412static int fw_decompress_xz_pages(struct device *dev, struct fw_priv *fw_priv,
413 size_t in_size, const void *in_buffer)
414{
415 struct xz_dec *xz_dec;
416 struct xz_buf xz_buf;
417 enum xz_ret xz_ret;
418 struct page *page;
419 int err = 0;
420
421 xz_dec = xz_dec_init(XZ_DYNALLOC, (u32)-1);
422 if (!xz_dec)
423 return -ENOMEM;
424
425 xz_buf.in_size = in_size;
426 xz_buf.in = in_buffer;
427 xz_buf.in_pos = 0;
428
429 fw_priv->is_paged_buf = true;
430 fw_priv->size = 0;
431 do {
432 if (fw_grow_paged_buf(fw_priv, fw_priv->nr_pages + 1)) {
433 err = -ENOMEM;
434 goto out;
435 }
436
437 /* decompress onto the new allocated page */
438 page = fw_priv->pages[fw_priv->nr_pages - 1];
439 xz_buf.out = kmap_local_page(page);
440 xz_buf.out_pos = 0;
441 xz_buf.out_size = PAGE_SIZE;
442 xz_ret = xz_dec_run(xz_dec, &xz_buf);
443 kunmap_local(xz_buf.out);
444 fw_priv->size += xz_buf.out_pos;
445 /* partial decompression means either end or error */
446 if (xz_buf.out_pos != PAGE_SIZE)
447 break;
448 } while (xz_ret == XZ_OK);
449
450 err = fw_decompress_xz_error(dev, xz_ret);
451 if (!err)
452 err = fw_map_paged_buf(fw_priv);
453
454 out:
455 xz_dec_end(xz_dec);
456 return err;
457}
458
459static int fw_decompress_xz(struct device *dev, struct fw_priv *fw_priv,
460 size_t in_size, const void *in_buffer)
461{
462 /* if the buffer is pre-allocated, we can perform in single-shot mode */
463 if (fw_priv->data)
464 return fw_decompress_xz_single(dev, fw_priv, in_size, in_buffer);
465 else
466 return fw_decompress_xz_pages(dev, fw_priv, in_size, in_buffer);
467}
468#endif /* CONFIG_FW_LOADER_COMPRESS_XZ */
469
470/* direct firmware loading support */
471static char fw_path_para[256];
472static const char * const fw_path[] = {
473 fw_path_para,
474 "/lib/firmware/updates/" UTS_RELEASE,
475 "/lib/firmware/updates",
476 "/lib/firmware/" UTS_RELEASE,
477 "/lib/firmware"
478};
479
480/*
481 * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
482 * from kernel command line because firmware_class is generally built in
483 * kernel instead of module.
484 */
485module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
486MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
487
488static int
489fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv,
490 const char *suffix,
491 int (*decompress)(struct device *dev,
492 struct fw_priv *fw_priv,
493 size_t in_size,
494 const void *in_buffer))
495{
496 size_t size;
497 int i, len, maxlen = 0;
498 int rc = -ENOENT;
499 char *path, *nt = NULL;
500 size_t msize = INT_MAX;
501 void *buffer = NULL;
502
503 /* Already populated data member means we're loading into a buffer */
504 if (!decompress && fw_priv->data) {
505 buffer = fw_priv->data;
506 msize = fw_priv->allocated_size;
507 }
508
509 path = __getname();
510 if (!path)
511 return -ENOMEM;
512
513 wait_for_initramfs();
514 for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
515 size_t file_size = 0;
516 size_t *file_size_ptr = NULL;
517
518 /* skip the unset customized path */
519 if (!fw_path[i][0])
520 continue;
521
522 /* strip off \n from customized path */
523 maxlen = strlen(fw_path[i]);
524 if (i == 0) {
525 nt = strchr(fw_path[i], '\n');
526 if (nt)
527 maxlen = nt - fw_path[i];
528 }
529
530 len = snprintf(path, PATH_MAX, "%.*s/%s%s",
531 maxlen, fw_path[i],
532 fw_priv->fw_name, suffix);
533 if (len >= PATH_MAX) {
534 rc = -ENAMETOOLONG;
535 break;
536 }
537
538 fw_priv->size = 0;
539
540 /*
541 * The total file size is only examined when doing a partial
542 * read; the "full read" case needs to fail if the whole
543 * firmware was not completely loaded.
544 */
545 if ((fw_priv->opt_flags & FW_OPT_PARTIAL) && buffer)
546 file_size_ptr = &file_size;
547
548 /* load firmware files from the mount namespace of init */
549 rc = kernel_read_file_from_path_initns(path, fw_priv->offset,
550 &buffer, msize,
551 file_size_ptr,
552 READING_FIRMWARE);
553 if (rc < 0) {
554 if (!(fw_priv->opt_flags & FW_OPT_NO_WARN)) {
555 if (rc != -ENOENT)
556 dev_warn(device,
557 "loading %s failed with error %d\n",
558 path, rc);
559 else
560 dev_dbg(device,
561 "loading %s failed for no such file or directory.\n",
562 path);
563 }
564 continue;
565 }
566 size = rc;
567 rc = 0;
568
569 dev_dbg(device, "Loading firmware from %s\n", path);
570 if (decompress) {
571 dev_dbg(device, "f/w decompressing %s\n",
572 fw_priv->fw_name);
573 rc = decompress(device, fw_priv, size, buffer);
574 /* discard the superfluous original content */
575 vfree(buffer);
576 buffer = NULL;
577 if (rc) {
578 fw_free_paged_buf(fw_priv);
579 continue;
580 }
581 } else {
582 dev_dbg(device, "direct-loading %s\n",
583 fw_priv->fw_name);
584 if (!fw_priv->data)
585 fw_priv->data = buffer;
586 fw_priv->size = size;
587 }
588 fw_state_done(fw_priv);
589 break;
590 }
591 __putname(path);
592
593 return rc;
594}
595
596/* firmware holds the ownership of pages */
597static void firmware_free_data(const struct firmware *fw)
598{
599 /* Loaded directly? */
600 if (!fw->priv) {
601 vfree(fw->data);
602 return;
603 }
604 free_fw_priv(fw->priv);
605}
606
607/* store the pages buffer info firmware from buf */
608static void fw_set_page_data(struct fw_priv *fw_priv, struct firmware *fw)
609{
610 fw->priv = fw_priv;
611 fw->size = fw_priv->size;
612 fw->data = fw_priv->data;
613
614 pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
615 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
616 (unsigned int)fw_priv->size);
617}
618
619#ifdef CONFIG_FW_CACHE
620static void fw_name_devm_release(struct device *dev, void *res)
621{
622 struct fw_name_devm *fwn = res;
623
624 if (fwn->magic == (unsigned long)&fw_cache)
625 pr_debug("%s: fw_name-%s devm-%p released\n",
626 __func__, fwn->name, res);
627 kfree_const(fwn->name);
628}
629
630static int fw_devm_match(struct device *dev, void *res,
631 void *match_data)
632{
633 struct fw_name_devm *fwn = res;
634
635 return (fwn->magic == (unsigned long)&fw_cache) &&
636 !strcmp(fwn->name, match_data);
637}
638
639static struct fw_name_devm *fw_find_devm_name(struct device *dev,
640 const char *name)
641{
642 struct fw_name_devm *fwn;
643
644 fwn = devres_find(dev, fw_name_devm_release,
645 fw_devm_match, (void *)name);
646 return fwn;
647}
648
649static bool fw_cache_is_setup(struct device *dev, const char *name)
650{
651 struct fw_name_devm *fwn;
652
653 fwn = fw_find_devm_name(dev, name);
654 if (fwn)
655 return true;
656
657 return false;
658}
659
660/* add firmware name into devres list */
661static int fw_add_devm_name(struct device *dev, const char *name)
662{
663 struct fw_name_devm *fwn;
664
665 if (fw_cache_is_setup(dev, name))
666 return 0;
667
668 fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm),
669 GFP_KERNEL);
670 if (!fwn)
671 return -ENOMEM;
672 fwn->name = kstrdup_const(name, GFP_KERNEL);
673 if (!fwn->name) {
674 devres_free(fwn);
675 return -ENOMEM;
676 }
677
678 fwn->magic = (unsigned long)&fw_cache;
679 devres_add(dev, fwn);
680
681 return 0;
682}
683#else
684static bool fw_cache_is_setup(struct device *dev, const char *name)
685{
686 return false;
687}
688
689static int fw_add_devm_name(struct device *dev, const char *name)
690{
691 return 0;
692}
693#endif
694
695int assign_fw(struct firmware *fw, struct device *device)
696{
697 struct fw_priv *fw_priv = fw->priv;
698 int ret;
699
700 mutex_lock(&fw_lock);
701 if (!fw_priv->size || fw_state_is_aborted(fw_priv)) {
702 mutex_unlock(&fw_lock);
703 return -ENOENT;
704 }
705
706 /*
707 * add firmware name into devres list so that we can auto cache
708 * and uncache firmware for device.
709 *
710 * device may has been deleted already, but the problem
711 * should be fixed in devres or driver core.
712 */
713 /* don't cache firmware handled without uevent */
714 if (device && (fw_priv->opt_flags & FW_OPT_UEVENT) &&
715 !(fw_priv->opt_flags & FW_OPT_NOCACHE)) {
716 ret = fw_add_devm_name(device, fw_priv->fw_name);
717 if (ret) {
718 mutex_unlock(&fw_lock);
719 return ret;
720 }
721 }
722
723 /*
724 * After caching firmware image is started, let it piggyback
725 * on request firmware.
726 */
727 if (!(fw_priv->opt_flags & FW_OPT_NOCACHE) &&
728 fw_priv->fwc->state == FW_LOADER_START_CACHE)
729 fw_cache_piggyback_on_request(fw_priv);
730
731 /* pass the pages buffer to driver at the last minute */
732 fw_set_page_data(fw_priv, fw);
733 mutex_unlock(&fw_lock);
734 return 0;
735}
736
737/* prepare firmware and firmware_buf structs;
738 * return 0 if a firmware is already assigned, 1 if need to load one,
739 * or a negative error code
740 */
741static int
742_request_firmware_prepare(struct firmware **firmware_p, const char *name,
743 struct device *device, void *dbuf, size_t size,
744 size_t offset, u32 opt_flags)
745{
746 struct firmware *firmware;
747 struct fw_priv *fw_priv;
748 int ret;
749
750 *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
751 if (!firmware) {
752 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
753 __func__);
754 return -ENOMEM;
755 }
756
757 if (firmware_request_builtin_buf(firmware, name, dbuf, size)) {
758 dev_dbg(device, "using built-in %s\n", name);
759 return 0; /* assigned */
760 }
761
762 ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv, dbuf, size,
763 offset, opt_flags);
764
765 /*
766 * bind with 'priv' now to avoid warning in failure path
767 * of requesting firmware.
768 */
769 firmware->priv = fw_priv;
770
771 if (ret > 0) {
772 ret = fw_state_wait(fw_priv);
773 if (!ret) {
774 fw_set_page_data(fw_priv, firmware);
775 return 0; /* assigned */
776 }
777 }
778
779 if (ret < 0)
780 return ret;
781 return 1; /* need to load */
782}
783
784/*
785 * Batched requests need only one wake, we need to do this step last due to the
786 * fallback mechanism. The buf is protected with kref_get(), and it won't be
787 * released until the last user calls release_firmware().
788 *
789 * Failed batched requests are possible as well, in such cases we just share
790 * the struct fw_priv and won't release it until all requests are woken
791 * and have gone through this same path.
792 */
793static void fw_abort_batch_reqs(struct firmware *fw)
794{
795 struct fw_priv *fw_priv;
796
797 /* Loaded directly? */
798 if (!fw || !fw->priv)
799 return;
800
801 fw_priv = fw->priv;
802 mutex_lock(&fw_lock);
803 if (!fw_state_is_aborted(fw_priv))
804 fw_state_aborted(fw_priv);
805 mutex_unlock(&fw_lock);
806}
807
808#if defined(CONFIG_FW_LOADER_DEBUG)
809#include <crypto/hash.h>
810#include <crypto/sha2.h>
811
812static void fw_log_firmware_info(const struct firmware *fw, const char *name, struct device *device)
813{
814 struct shash_desc *shash;
815 struct crypto_shash *alg;
816 u8 *sha256buf;
817 char *outbuf;
818
819 alg = crypto_alloc_shash("sha256", 0, 0);
820 if (IS_ERR(alg))
821 return;
822
823 sha256buf = kmalloc(SHA256_DIGEST_SIZE, GFP_KERNEL);
824 outbuf = kmalloc(SHA256_BLOCK_SIZE + 1, GFP_KERNEL);
825 shash = kmalloc(sizeof(*shash) + crypto_shash_descsize(alg), GFP_KERNEL);
826 if (!sha256buf || !outbuf || !shash)
827 goto out_free;
828
829 shash->tfm = alg;
830
831 if (crypto_shash_digest(shash, fw->data, fw->size, sha256buf) < 0)
832 goto out_free;
833
834 for (int i = 0; i < SHA256_DIGEST_SIZE; i++)
835 sprintf(&outbuf[i * 2], "%02x", sha256buf[i]);
836 outbuf[SHA256_BLOCK_SIZE] = 0;
837 dev_dbg(device, "Loaded FW: %s, sha256: %s\n", name, outbuf);
838
839out_free:
840 kfree(shash);
841 kfree(outbuf);
842 kfree(sha256buf);
843 crypto_free_shash(alg);
844}
845#else
846static void fw_log_firmware_info(const struct firmware *fw, const char *name,
847 struct device *device)
848{}
849#endif
850
851/*
852 * Reject firmware file names with ".." path components.
853 * There are drivers that construct firmware file names from device-supplied
854 * strings, and we don't want some device to be able to tell us "I would like to
855 * be sent my firmware from ../../../etc/shadow, please".
856 *
857 * Search for ".." surrounded by either '/' or start/end of string.
858 *
859 * This intentionally only looks at the firmware name, not at the firmware base
860 * directory or at symlink contents.
861 */
862static bool name_contains_dotdot(const char *name)
863{
864 size_t name_len = strlen(name);
865
866 return strcmp(name, "..") == 0 || strncmp(name, "../", 3) == 0 ||
867 strstr(name, "/../") != NULL ||
868 (name_len >= 3 && strcmp(name+name_len-3, "/..") == 0);
869}
870
871/* called from request_firmware() and request_firmware_work_func() */
872static int
873_request_firmware(const struct firmware **firmware_p, const char *name,
874 struct device *device, void *buf, size_t size,
875 size_t offset, u32 opt_flags)
876{
877 struct firmware *fw = NULL;
878 struct cred *kern_cred = NULL;
879 const struct cred *old_cred;
880 bool nondirect = false;
881 int ret;
882
883 if (!firmware_p)
884 return -EINVAL;
885
886 if (!name || name[0] == '\0') {
887 ret = -EINVAL;
888 goto out;
889 }
890
891 if (name_contains_dotdot(name)) {
892 dev_warn(device,
893 "Firmware load for '%s' refused, path contains '..' component\n",
894 name);
895 ret = -EINVAL;
896 goto out;
897 }
898
899 ret = _request_firmware_prepare(&fw, name, device, buf, size,
900 offset, opt_flags);
901 if (ret <= 0) /* error or already assigned */
902 goto out;
903
904 /*
905 * We are about to try to access the firmware file. Because we may have been
906 * called by a driver when serving an unrelated request from userland, we use
907 * the kernel credentials to read the file.
908 */
909 kern_cred = prepare_kernel_cred(&init_task);
910 if (!kern_cred) {
911 ret = -ENOMEM;
912 goto out;
913 }
914 old_cred = override_creds(kern_cred);
915
916 ret = fw_get_filesystem_firmware(device, fw->priv, "", NULL);
917
918 /* Only full reads can support decompression, platform, and sysfs. */
919 if (!(opt_flags & FW_OPT_PARTIAL))
920 nondirect = true;
921
922#ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD
923 if (ret == -ENOENT && nondirect)
924 ret = fw_get_filesystem_firmware(device, fw->priv, ".zst",
925 fw_decompress_zstd);
926#endif
927#ifdef CONFIG_FW_LOADER_COMPRESS_XZ
928 if (ret == -ENOENT && nondirect)
929 ret = fw_get_filesystem_firmware(device, fw->priv, ".xz",
930 fw_decompress_xz);
931#endif
932 if (ret == -ENOENT && nondirect)
933 ret = firmware_fallback_platform(fw->priv);
934
935 if (ret) {
936 if (!(opt_flags & FW_OPT_NO_WARN))
937 dev_warn(device,
938 "Direct firmware load for %s failed with error %d\n",
939 name, ret);
940 if (nondirect)
941 ret = firmware_fallback_sysfs(fw, name, device,
942 opt_flags, ret);
943 } else
944 ret = assign_fw(fw, device);
945
946 revert_creds(old_cred);
947 put_cred(kern_cred);
948
949out:
950 if (ret < 0) {
951 fw_abort_batch_reqs(fw);
952 release_firmware(fw);
953 fw = NULL;
954 } else {
955 fw_log_firmware_info(fw, name, device);
956 }
957
958 *firmware_p = fw;
959 return ret;
960}
961
962/**
963 * request_firmware() - send firmware request and wait for it
964 * @firmware_p: pointer to firmware image
965 * @name: name of firmware file
966 * @device: device for which firmware is being loaded
967 *
968 * @firmware_p will be used to return a firmware image by the name
969 * of @name for device @device.
970 *
971 * Should be called from user context where sleeping is allowed.
972 *
973 * @name will be used as $FIRMWARE in the uevent environment and
974 * should be distinctive enough not to be confused with any other
975 * firmware image for this or any other device.
976 * It must not contain any ".." path components - "foo/bar..bin" is
977 * allowed, but "foo/../bar.bin" is not.
978 *
979 * Caller must hold the reference count of @device.
980 *
981 * The function can be called safely inside device's suspend and
982 * resume callback.
983 **/
984int
985request_firmware(const struct firmware **firmware_p, const char *name,
986 struct device *device)
987{
988 int ret;
989
990 /* Need to pin this module until return */
991 __module_get(THIS_MODULE);
992 ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
993 FW_OPT_UEVENT);
994 module_put(THIS_MODULE);
995 return ret;
996}
997EXPORT_SYMBOL(request_firmware);
998
999/**
1000 * firmware_request_nowarn() - request for an optional fw module
1001 * @firmware: pointer to firmware image
1002 * @name: name of firmware file
1003 * @device: device for which firmware is being loaded
1004 *
1005 * This function is similar in behaviour to request_firmware(), except it
1006 * doesn't produce warning messages when the file is not found. The sysfs
1007 * fallback mechanism is enabled if direct filesystem lookup fails. However,
1008 * failures to find the firmware file with it are still suppressed. It is
1009 * therefore up to the driver to check for the return value of this call and to
1010 * decide when to inform the users of errors.
1011 **/
1012int firmware_request_nowarn(const struct firmware **firmware, const char *name,
1013 struct device *device)
1014{
1015 int ret;
1016
1017 /* Need to pin this module until return */
1018 __module_get(THIS_MODULE);
1019 ret = _request_firmware(firmware, name, device, NULL, 0, 0,
1020 FW_OPT_UEVENT | FW_OPT_NO_WARN);
1021 module_put(THIS_MODULE);
1022 return ret;
1023}
1024EXPORT_SYMBOL_GPL(firmware_request_nowarn);
1025
1026/**
1027 * request_firmware_direct() - load firmware directly without usermode helper
1028 * @firmware_p: pointer to firmware image
1029 * @name: name of firmware file
1030 * @device: device for which firmware is being loaded
1031 *
1032 * This function works pretty much like request_firmware(), but this doesn't
1033 * fall back to usermode helper even if the firmware couldn't be loaded
1034 * directly from fs. Hence it's useful for loading optional firmwares, which
1035 * aren't always present, without extra long timeouts of udev.
1036 **/
1037int request_firmware_direct(const struct firmware **firmware_p,
1038 const char *name, struct device *device)
1039{
1040 int ret;
1041
1042 __module_get(THIS_MODULE);
1043 ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
1044 FW_OPT_UEVENT | FW_OPT_NO_WARN |
1045 FW_OPT_NOFALLBACK_SYSFS);
1046 module_put(THIS_MODULE);
1047 return ret;
1048}
1049EXPORT_SYMBOL_GPL(request_firmware_direct);
1050
1051/**
1052 * firmware_request_platform() - request firmware with platform-fw fallback
1053 * @firmware: pointer to firmware image
1054 * @name: name of firmware file
1055 * @device: device for which firmware is being loaded
1056 *
1057 * This function is similar in behaviour to request_firmware, except that if
1058 * direct filesystem lookup fails, it will fallback to looking for a copy of the
1059 * requested firmware embedded in the platform's main (e.g. UEFI) firmware.
1060 **/
1061int firmware_request_platform(const struct firmware **firmware,
1062 const char *name, struct device *device)
1063{
1064 int ret;
1065
1066 /* Need to pin this module until return */
1067 __module_get(THIS_MODULE);
1068 ret = _request_firmware(firmware, name, device, NULL, 0, 0,
1069 FW_OPT_UEVENT | FW_OPT_FALLBACK_PLATFORM);
1070 module_put(THIS_MODULE);
1071 return ret;
1072}
1073EXPORT_SYMBOL_GPL(firmware_request_platform);
1074
1075/**
1076 * firmware_request_cache() - cache firmware for suspend so resume can use it
1077 * @device: device for which firmware should be cached for
1078 * @name: name of firmware file
1079 *
1080 * There are some devices with an optimization that enables the device to not
1081 * require loading firmware on system reboot. This optimization may still
1082 * require the firmware present on resume from suspend. This routine can be
1083 * used to ensure the firmware is present on resume from suspend in these
1084 * situations. This helper is not compatible with drivers which use
1085 * request_firmware_into_buf() or request_firmware_nowait() with no uevent set.
1086 **/
1087int firmware_request_cache(struct device *device, const char *name)
1088{
1089 int ret;
1090
1091 mutex_lock(&fw_lock);
1092 ret = fw_add_devm_name(device, name);
1093 mutex_unlock(&fw_lock);
1094
1095 return ret;
1096}
1097EXPORT_SYMBOL_GPL(firmware_request_cache);
1098
1099/**
1100 * request_firmware_into_buf() - load firmware into a previously allocated buffer
1101 * @firmware_p: pointer to firmware image
1102 * @name: name of firmware file
1103 * @device: device for which firmware is being loaded and DMA region allocated
1104 * @buf: address of buffer to load firmware into
1105 * @size: size of buffer
1106 *
1107 * This function works pretty much like request_firmware(), but it doesn't
1108 * allocate a buffer to hold the firmware data. Instead, the firmware
1109 * is loaded directly into the buffer pointed to by @buf and the @firmware_p
1110 * data member is pointed at @buf.
1111 *
1112 * This function doesn't cache firmware either.
1113 */
1114int
1115request_firmware_into_buf(const struct firmware **firmware_p, const char *name,
1116 struct device *device, void *buf, size_t size)
1117{
1118 int ret;
1119
1120 if (fw_cache_is_setup(device, name))
1121 return -EOPNOTSUPP;
1122
1123 __module_get(THIS_MODULE);
1124 ret = _request_firmware(firmware_p, name, device, buf, size, 0,
1125 FW_OPT_UEVENT | FW_OPT_NOCACHE);
1126 module_put(THIS_MODULE);
1127 return ret;
1128}
1129EXPORT_SYMBOL(request_firmware_into_buf);
1130
1131/**
1132 * request_partial_firmware_into_buf() - load partial firmware into a previously allocated buffer
1133 * @firmware_p: pointer to firmware image
1134 * @name: name of firmware file
1135 * @device: device for which firmware is being loaded and DMA region allocated
1136 * @buf: address of buffer to load firmware into
1137 * @size: size of buffer
1138 * @offset: offset into file to read
1139 *
1140 * This function works pretty much like request_firmware_into_buf except
1141 * it allows a partial read of the file.
1142 */
1143int
1144request_partial_firmware_into_buf(const struct firmware **firmware_p,
1145 const char *name, struct device *device,
1146 void *buf, size_t size, size_t offset)
1147{
1148 int ret;
1149
1150 if (fw_cache_is_setup(device, name))
1151 return -EOPNOTSUPP;
1152
1153 __module_get(THIS_MODULE);
1154 ret = _request_firmware(firmware_p, name, device, buf, size, offset,
1155 FW_OPT_UEVENT | FW_OPT_NOCACHE |
1156 FW_OPT_PARTIAL);
1157 module_put(THIS_MODULE);
1158 return ret;
1159}
1160EXPORT_SYMBOL(request_partial_firmware_into_buf);
1161
1162/**
1163 * release_firmware() - release the resource associated with a firmware image
1164 * @fw: firmware resource to release
1165 **/
1166void release_firmware(const struct firmware *fw)
1167{
1168 if (fw) {
1169 if (!firmware_is_builtin(fw))
1170 firmware_free_data(fw);
1171 kfree(fw);
1172 }
1173}
1174EXPORT_SYMBOL(release_firmware);
1175
1176/* Async support */
1177struct firmware_work {
1178 struct work_struct work;
1179 struct module *module;
1180 const char *name;
1181 struct device *device;
1182 void *context;
1183 void (*cont)(const struct firmware *fw, void *context);
1184 u32 opt_flags;
1185};
1186
1187static void request_firmware_work_func(struct work_struct *work)
1188{
1189 struct firmware_work *fw_work;
1190 const struct firmware *fw;
1191
1192 fw_work = container_of(work, struct firmware_work, work);
1193
1194 _request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0, 0,
1195 fw_work->opt_flags);
1196 fw_work->cont(fw, fw_work->context);
1197 put_device(fw_work->device); /* taken in request_firmware_nowait() */
1198
1199 module_put(fw_work->module);
1200 kfree_const(fw_work->name);
1201 kfree(fw_work);
1202}
1203
1204
1205static int _request_firmware_nowait(
1206 struct module *module, bool uevent,
1207 const char *name, struct device *device, gfp_t gfp, void *context,
1208 void (*cont)(const struct firmware *fw, void *context), bool nowarn)
1209{
1210 struct firmware_work *fw_work;
1211
1212 fw_work = kzalloc(sizeof(struct firmware_work), gfp);
1213 if (!fw_work)
1214 return -ENOMEM;
1215
1216 fw_work->module = module;
1217 fw_work->name = kstrdup_const(name, gfp);
1218 if (!fw_work->name) {
1219 kfree(fw_work);
1220 return -ENOMEM;
1221 }
1222 fw_work->device = device;
1223 fw_work->context = context;
1224 fw_work->cont = cont;
1225 fw_work->opt_flags = FW_OPT_NOWAIT |
1226 (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER) |
1227 (nowarn ? FW_OPT_NO_WARN : 0);
1228
1229 if (!uevent && fw_cache_is_setup(device, name)) {
1230 kfree_const(fw_work->name);
1231 kfree(fw_work);
1232 return -EOPNOTSUPP;
1233 }
1234
1235 if (!try_module_get(module)) {
1236 kfree_const(fw_work->name);
1237 kfree(fw_work);
1238 return -EFAULT;
1239 }
1240
1241 get_device(fw_work->device);
1242 INIT_WORK(&fw_work->work, request_firmware_work_func);
1243 schedule_work(&fw_work->work);
1244 return 0;
1245}
1246
1247/**
1248 * request_firmware_nowait() - asynchronous version of request_firmware
1249 * @module: module requesting the firmware
1250 * @uevent: sends uevent to copy the firmware image if this flag
1251 * is non-zero else the firmware copy must be done manually.
1252 * @name: name of firmware file
1253 * @device: device for which firmware is being loaded
1254 * @gfp: allocation flags
1255 * @context: will be passed over to @cont, and
1256 * @fw may be %NULL if firmware request fails.
1257 * @cont: function will be called asynchronously when the firmware
1258 * request is over.
1259 *
1260 * Caller must hold the reference count of @device.
1261 *
1262 * Asynchronous variant of request_firmware() for user contexts:
1263 * - sleep for as small periods as possible since it may
1264 * increase kernel boot time of built-in device drivers
1265 * requesting firmware in their ->probe() methods, if
1266 * @gfp is GFP_KERNEL.
1267 *
1268 * - can't sleep at all if @gfp is GFP_ATOMIC.
1269 **/
1270int request_firmware_nowait(
1271 struct module *module, bool uevent,
1272 const char *name, struct device *device, gfp_t gfp, void *context,
1273 void (*cont)(const struct firmware *fw, void *context))
1274{
1275 return _request_firmware_nowait(module, uevent, name, device, gfp,
1276 context, cont, false);
1277
1278}
1279EXPORT_SYMBOL(request_firmware_nowait);
1280
1281/**
1282 * firmware_request_nowait_nowarn() - async version of request_firmware_nowarn
1283 * @module: module requesting the firmware
1284 * @name: name of firmware file
1285 * @device: device for which firmware is being loaded
1286 * @gfp: allocation flags
1287 * @context: will be passed over to @cont, and
1288 * @fw may be %NULL if firmware request fails.
1289 * @cont: function will be called asynchronously when the firmware
1290 * request is over.
1291 *
1292 * Similar in function to request_firmware_nowait(), but doesn't print a warning
1293 * when the firmware file could not be found and always sends a uevent to copy
1294 * the firmware image.
1295 */
1296int firmware_request_nowait_nowarn(
1297 struct module *module, const char *name,
1298 struct device *device, gfp_t gfp, void *context,
1299 void (*cont)(const struct firmware *fw, void *context))
1300{
1301 return _request_firmware_nowait(module, FW_ACTION_UEVENT, name, device,
1302 gfp, context, cont, true);
1303}
1304EXPORT_SYMBOL_GPL(firmware_request_nowait_nowarn);
1305
1306#ifdef CONFIG_FW_CACHE
1307static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1308
1309/**
1310 * cache_firmware() - cache one firmware image in kernel memory space
1311 * @fw_name: the firmware image name
1312 *
1313 * Cache firmware in kernel memory so that drivers can use it when
1314 * system isn't ready for them to request firmware image from userspace.
1315 * Once it returns successfully, driver can use request_firmware or its
1316 * nowait version to get the cached firmware without any interacting
1317 * with userspace
1318 *
1319 * Return 0 if the firmware image has been cached successfully
1320 * Return !0 otherwise
1321 *
1322 */
1323static int cache_firmware(const char *fw_name)
1324{
1325 int ret;
1326 const struct firmware *fw;
1327
1328 pr_debug("%s: %s\n", __func__, fw_name);
1329
1330 ret = request_firmware(&fw, fw_name, NULL);
1331 if (!ret)
1332 kfree(fw);
1333
1334 pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1335
1336 return ret;
1337}
1338
1339static struct fw_priv *lookup_fw_priv(const char *fw_name)
1340{
1341 struct fw_priv *tmp;
1342 struct firmware_cache *fwc = &fw_cache;
1343
1344 spin_lock(&fwc->lock);
1345 tmp = __lookup_fw_priv(fw_name);
1346 spin_unlock(&fwc->lock);
1347
1348 return tmp;
1349}
1350
1351/**
1352 * uncache_firmware() - remove one cached firmware image
1353 * @fw_name: the firmware image name
1354 *
1355 * Uncache one firmware image which has been cached successfully
1356 * before.
1357 *
1358 * Return 0 if the firmware cache has been removed successfully
1359 * Return !0 otherwise
1360 *
1361 */
1362static int uncache_firmware(const char *fw_name)
1363{
1364 struct fw_priv *fw_priv;
1365 struct firmware fw;
1366
1367 pr_debug("%s: %s\n", __func__, fw_name);
1368
1369 if (firmware_request_builtin(&fw, fw_name))
1370 return 0;
1371
1372 fw_priv = lookup_fw_priv(fw_name);
1373 if (fw_priv) {
1374 free_fw_priv(fw_priv);
1375 return 0;
1376 }
1377
1378 return -EINVAL;
1379}
1380
1381static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1382{
1383 struct fw_cache_entry *fce;
1384
1385 fce = kzalloc(sizeof(*fce), GFP_ATOMIC);
1386 if (!fce)
1387 goto exit;
1388
1389 fce->name = kstrdup_const(name, GFP_ATOMIC);
1390 if (!fce->name) {
1391 kfree(fce);
1392 fce = NULL;
1393 goto exit;
1394 }
1395exit:
1396 return fce;
1397}
1398
1399static int __fw_entry_found(const char *name)
1400{
1401 struct firmware_cache *fwc = &fw_cache;
1402 struct fw_cache_entry *fce;
1403
1404 list_for_each_entry(fce, &fwc->fw_names, list) {
1405 if (!strcmp(fce->name, name))
1406 return 1;
1407 }
1408 return 0;
1409}
1410
1411static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv)
1412{
1413 const char *name = fw_priv->fw_name;
1414 struct firmware_cache *fwc = fw_priv->fwc;
1415 struct fw_cache_entry *fce;
1416
1417 spin_lock(&fwc->name_lock);
1418 if (__fw_entry_found(name))
1419 goto found;
1420
1421 fce = alloc_fw_cache_entry(name);
1422 if (fce) {
1423 list_add(&fce->list, &fwc->fw_names);
1424 kref_get(&fw_priv->ref);
1425 pr_debug("%s: fw: %s\n", __func__, name);
1426 }
1427found:
1428 spin_unlock(&fwc->name_lock);
1429}
1430
1431static void free_fw_cache_entry(struct fw_cache_entry *fce)
1432{
1433 kfree_const(fce->name);
1434 kfree(fce);
1435}
1436
1437static void __async_dev_cache_fw_image(void *fw_entry,
1438 async_cookie_t cookie)
1439{
1440 struct fw_cache_entry *fce = fw_entry;
1441 struct firmware_cache *fwc = &fw_cache;
1442 int ret;
1443
1444 ret = cache_firmware(fce->name);
1445 if (ret) {
1446 spin_lock(&fwc->name_lock);
1447 list_del(&fce->list);
1448 spin_unlock(&fwc->name_lock);
1449
1450 free_fw_cache_entry(fce);
1451 }
1452}
1453
1454/* called with dev->devres_lock held */
1455static void dev_create_fw_entry(struct device *dev, void *res,
1456 void *data)
1457{
1458 struct fw_name_devm *fwn = res;
1459 const char *fw_name = fwn->name;
1460 struct list_head *head = data;
1461 struct fw_cache_entry *fce;
1462
1463 fce = alloc_fw_cache_entry(fw_name);
1464 if (fce)
1465 list_add(&fce->list, head);
1466}
1467
1468static int devm_name_match(struct device *dev, void *res,
1469 void *match_data)
1470{
1471 struct fw_name_devm *fwn = res;
1472 return (fwn->magic == (unsigned long)match_data);
1473}
1474
1475static void dev_cache_fw_image(struct device *dev, void *data)
1476{
1477 LIST_HEAD(todo);
1478 struct fw_cache_entry *fce;
1479 struct fw_cache_entry *fce_next;
1480 struct firmware_cache *fwc = &fw_cache;
1481
1482 devres_for_each_res(dev, fw_name_devm_release,
1483 devm_name_match, &fw_cache,
1484 dev_create_fw_entry, &todo);
1485
1486 list_for_each_entry_safe(fce, fce_next, &todo, list) {
1487 list_del(&fce->list);
1488
1489 spin_lock(&fwc->name_lock);
1490 /* only one cache entry for one firmware */
1491 if (!__fw_entry_found(fce->name)) {
1492 list_add(&fce->list, &fwc->fw_names);
1493 } else {
1494 free_fw_cache_entry(fce);
1495 fce = NULL;
1496 }
1497 spin_unlock(&fwc->name_lock);
1498
1499 if (fce)
1500 async_schedule_domain(__async_dev_cache_fw_image,
1501 (void *)fce,
1502 &fw_cache_domain);
1503 }
1504}
1505
1506static void __device_uncache_fw_images(void)
1507{
1508 struct firmware_cache *fwc = &fw_cache;
1509 struct fw_cache_entry *fce;
1510
1511 spin_lock(&fwc->name_lock);
1512 while (!list_empty(&fwc->fw_names)) {
1513 fce = list_entry(fwc->fw_names.next,
1514 struct fw_cache_entry, list);
1515 list_del(&fce->list);
1516 spin_unlock(&fwc->name_lock);
1517
1518 uncache_firmware(fce->name);
1519 free_fw_cache_entry(fce);
1520
1521 spin_lock(&fwc->name_lock);
1522 }
1523 spin_unlock(&fwc->name_lock);
1524}
1525
1526/**
1527 * device_cache_fw_images() - cache devices' firmware
1528 *
1529 * If one device called request_firmware or its nowait version
1530 * successfully before, the firmware names are recored into the
1531 * device's devres link list, so device_cache_fw_images can call
1532 * cache_firmware() to cache these firmwares for the device,
1533 * then the device driver can load its firmwares easily at
1534 * time when system is not ready to complete loading firmware.
1535 */
1536static void device_cache_fw_images(void)
1537{
1538 struct firmware_cache *fwc = &fw_cache;
1539 DEFINE_WAIT(wait);
1540
1541 pr_debug("%s\n", __func__);
1542
1543 /* cancel uncache work */
1544 cancel_delayed_work_sync(&fwc->work);
1545
1546 fw_fallback_set_cache_timeout();
1547
1548 mutex_lock(&fw_lock);
1549 fwc->state = FW_LOADER_START_CACHE;
1550 dpm_for_each_dev(NULL, dev_cache_fw_image);
1551 mutex_unlock(&fw_lock);
1552
1553 /* wait for completion of caching firmware for all devices */
1554 async_synchronize_full_domain(&fw_cache_domain);
1555
1556 fw_fallback_set_default_timeout();
1557}
1558
1559/**
1560 * device_uncache_fw_images() - uncache devices' firmware
1561 *
1562 * uncache all firmwares which have been cached successfully
1563 * by device_uncache_fw_images earlier
1564 */
1565static void device_uncache_fw_images(void)
1566{
1567 pr_debug("%s\n", __func__);
1568 __device_uncache_fw_images();
1569}
1570
1571static void device_uncache_fw_images_work(struct work_struct *work)
1572{
1573 device_uncache_fw_images();
1574}
1575
1576/**
1577 * device_uncache_fw_images_delay() - uncache devices firmwares
1578 * @delay: number of milliseconds to delay uncache device firmwares
1579 *
1580 * uncache all devices's firmwares which has been cached successfully
1581 * by device_cache_fw_images after @delay milliseconds.
1582 */
1583static void device_uncache_fw_images_delay(unsigned long delay)
1584{
1585 queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1586 msecs_to_jiffies(delay));
1587}
1588
1589static int fw_pm_notify(struct notifier_block *notify_block,
1590 unsigned long mode, void *unused)
1591{
1592 switch (mode) {
1593 case PM_HIBERNATION_PREPARE:
1594 case PM_SUSPEND_PREPARE:
1595 case PM_RESTORE_PREPARE:
1596 /*
1597 * Here, kill pending fallback requests will only kill
1598 * non-uevent firmware request to avoid stalling suspend.
1599 */
1600 kill_pending_fw_fallback_reqs(false);
1601 device_cache_fw_images();
1602 break;
1603
1604 case PM_POST_SUSPEND:
1605 case PM_POST_HIBERNATION:
1606 case PM_POST_RESTORE:
1607 /*
1608 * In case that system sleep failed and syscore_suspend is
1609 * not called.
1610 */
1611 mutex_lock(&fw_lock);
1612 fw_cache.state = FW_LOADER_NO_CACHE;
1613 mutex_unlock(&fw_lock);
1614
1615 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1616 break;
1617 }
1618
1619 return 0;
1620}
1621
1622/* stop caching firmware once syscore_suspend is reached */
1623static int fw_suspend(void)
1624{
1625 fw_cache.state = FW_LOADER_NO_CACHE;
1626 return 0;
1627}
1628
1629static struct syscore_ops fw_syscore_ops = {
1630 .suspend = fw_suspend,
1631};
1632
1633static int __init register_fw_pm_ops(void)
1634{
1635 int ret;
1636
1637 spin_lock_init(&fw_cache.name_lock);
1638 INIT_LIST_HEAD(&fw_cache.fw_names);
1639
1640 INIT_DELAYED_WORK(&fw_cache.work,
1641 device_uncache_fw_images_work);
1642
1643 fw_cache.pm_notify.notifier_call = fw_pm_notify;
1644 ret = register_pm_notifier(&fw_cache.pm_notify);
1645 if (ret)
1646 return ret;
1647
1648 register_syscore_ops(&fw_syscore_ops);
1649
1650 return ret;
1651}
1652
1653static inline void unregister_fw_pm_ops(void)
1654{
1655 unregister_syscore_ops(&fw_syscore_ops);
1656 unregister_pm_notifier(&fw_cache.pm_notify);
1657}
1658#else
1659static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv)
1660{
1661}
1662static inline int register_fw_pm_ops(void)
1663{
1664 return 0;
1665}
1666static inline void unregister_fw_pm_ops(void)
1667{
1668}
1669#endif
1670
1671static void __init fw_cache_init(void)
1672{
1673 spin_lock_init(&fw_cache.lock);
1674 INIT_LIST_HEAD(&fw_cache.head);
1675 fw_cache.state = FW_LOADER_NO_CACHE;
1676}
1677
1678static int fw_shutdown_notify(struct notifier_block *unused1,
1679 unsigned long unused2, void *unused3)
1680{
1681 /*
1682 * Kill all pending fallback requests to avoid both stalling shutdown,
1683 * and avoid a deadlock with the usermode_lock.
1684 */
1685 kill_pending_fw_fallback_reqs(true);
1686
1687 return NOTIFY_DONE;
1688}
1689
1690static struct notifier_block fw_shutdown_nb = {
1691 .notifier_call = fw_shutdown_notify,
1692};
1693
1694static int __init firmware_class_init(void)
1695{
1696 int ret;
1697
1698 /* No need to unfold these on exit */
1699 fw_cache_init();
1700
1701 ret = register_fw_pm_ops();
1702 if (ret)
1703 return ret;
1704
1705 ret = register_reboot_notifier(&fw_shutdown_nb);
1706 if (ret)
1707 goto out;
1708
1709 return register_sysfs_loader();
1710
1711out:
1712 unregister_fw_pm_ops();
1713 return ret;
1714}
1715
1716static void __exit firmware_class_exit(void)
1717{
1718 unregister_fw_pm_ops();
1719 unregister_reboot_notifier(&fw_shutdown_nb);
1720 unregister_sysfs_loader();
1721}
1722
1723fs_initcall(firmware_class_init);
1724module_exit(firmware_class_exit);