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
47 MODULE_AUTHOR("Manuel Estrada Sainz");
48 MODULE_DESCRIPTION("Multi purpose firmware loading support");
49 MODULE_LICENSE("GPL");
50
51 struct 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
73 struct fw_cache_entry {
74 struct list_head list;
75 const char *name;
76 };
77
78 struct fw_name_devm {
79 unsigned long magic;
80 const char *name;
81 };
82
to_fw_priv(struct kref * ref)83 static 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 */
93 DEFINE_MUTEX(fw_lock);
94
95 struct firmware_cache fw_cache;
96 bool fw_load_abort_all;
97
fw_state_init(struct fw_priv * fw_priv)98 void 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
fw_state_wait(struct fw_priv * fw_priv)106 static inline int fw_state_wait(struct fw_priv *fw_priv)
107 {
108 return __fw_state_wait_common(fw_priv, MAX_SCHEDULE_TIMEOUT);
109 }
110
111 static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv);
112
__allocate_fw_priv(const char * fw_name,struct firmware_cache * fwc,void * dbuf,size_t size,size_t offset,u32 opt_flags)113 static 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
__lookup_fw_priv(const char * fw_name)156 static 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 */
alloc_lookup_fw_priv(const char * fw_name,struct firmware_cache * fwc,struct fw_priv ** fw_priv,void * dbuf,size_t size,size_t offset,u32 opt_flags)168 int 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
__free_fw_priv(struct kref * ref)203 static 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
free_fw_priv(struct fw_priv * fw_priv)225 void 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
fw_is_paged_buf(struct fw_priv * fw_priv)234 bool fw_is_paged_buf(struct fw_priv *fw_priv)
235 {
236 return fw_priv->is_paged_buf;
237 }
238
fw_free_paged_buf(struct fw_priv * fw_priv)239 void 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
fw_grow_paged_buf(struct fw_priv * fw_priv,int pages_needed)258 int 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
fw_map_paged_buf(struct fw_priv * fw_priv)291 int 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
fw_decompress_zstd(struct device * dev,struct fw_priv * fw_priv,size_t in_size,const void * in_buffer)311 static 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 */
fw_decompress_xz_error(struct device * dev,enum xz_ret xz_ret)376 static 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 */
fw_decompress_xz_single(struct device * dev,struct fw_priv * fw_priv,size_t in_size,const void * in_buffer)386 static 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 */
fw_decompress_xz_pages(struct device * dev,struct fw_priv * fw_priv,size_t in_size,const void * in_buffer)412 static 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
fw_decompress_xz(struct device * dev,struct fw_priv * fw_priv,size_t in_size,const void * in_buffer)459 static 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 */
471 static char fw_path_para[256];
472 static 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 */
485 module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
486 MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
487
488 static int
fw_get_filesystem_firmware(struct device * device,struct fw_priv * fw_priv,const char * suffix,int (* decompress)(struct device * dev,struct fw_priv * fw_priv,size_t in_size,const void * in_buffer))489 fw_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 */
firmware_free_data(const struct firmware * fw)597 static 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 */
fw_set_page_data(struct fw_priv * fw_priv,struct firmware * fw)608 static 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
fw_name_devm_release(struct device * dev,void * res)620 static 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
fw_devm_match(struct device * dev,void * res,void * match_data)630 static 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
fw_find_devm_name(struct device * dev,const char * name)639 static 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
fw_cache_is_setup(struct device * dev,const char * name)649 static 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 */
fw_add_devm_name(struct device * dev,const char * name)661 static 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
fw_cache_is_setup(struct device * dev,const char * name)684 static bool fw_cache_is_setup(struct device *dev, const char *name)
685 {
686 return false;
687 }
688
fw_add_devm_name(struct device * dev,const char * name)689 static int fw_add_devm_name(struct device *dev, const char *name)
690 {
691 return 0;
692 }
693 #endif
694
assign_fw(struct firmware * fw,struct device * device)695 int 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 */
741 static int
_request_firmware_prepare(struct firmware ** firmware_p,const char * name,struct device * device,void * dbuf,size_t size,size_t offset,u32 opt_flags)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 */
fw_abort_batch_reqs(struct firmware * fw)793 static 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
fw_log_firmware_info(const struct firmware * fw,const char * name,struct device * device)812 static 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_shash;
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
839 out_shash:
840 crypto_free_shash(alg);
841 out_free:
842 kfree(shash);
843 kfree(outbuf);
844 kfree(sha256buf);
845 }
846 #else
fw_log_firmware_info(const struct firmware * fw,const char * name,struct device * device)847 static void fw_log_firmware_info(const struct firmware *fw, const char *name,
848 struct device *device)
849 {}
850 #endif
851
852 /* called from request_firmware() and request_firmware_work_func() */
853 static int
_request_firmware(const struct firmware ** firmware_p,const char * name,struct device * device,void * buf,size_t size,size_t offset,u32 opt_flags)854 _request_firmware(const struct firmware **firmware_p, const char *name,
855 struct device *device, void *buf, size_t size,
856 size_t offset, u32 opt_flags)
857 {
858 struct firmware *fw = NULL;
859 struct cred *kern_cred = NULL;
860 const struct cred *old_cred;
861 bool nondirect = false;
862 int ret;
863
864 if (!firmware_p)
865 return -EINVAL;
866
867 if (!name || name[0] == '\0') {
868 ret = -EINVAL;
869 goto out;
870 }
871
872 ret = _request_firmware_prepare(&fw, name, device, buf, size,
873 offset, opt_flags);
874 if (ret <= 0) /* error or already assigned */
875 goto out;
876
877 /*
878 * We are about to try to access the firmware file. Because we may have been
879 * called by a driver when serving an unrelated request from userland, we use
880 * the kernel credentials to read the file.
881 */
882 kern_cred = prepare_kernel_cred(&init_task);
883 if (!kern_cred) {
884 ret = -ENOMEM;
885 goto out;
886 }
887 old_cred = override_creds(kern_cred);
888
889 ret = fw_get_filesystem_firmware(device, fw->priv, "", NULL);
890
891 /* Only full reads can support decompression, platform, and sysfs. */
892 if (!(opt_flags & FW_OPT_PARTIAL))
893 nondirect = true;
894
895 #ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD
896 if (ret == -ENOENT && nondirect)
897 ret = fw_get_filesystem_firmware(device, fw->priv, ".zst",
898 fw_decompress_zstd);
899 #endif
900 #ifdef CONFIG_FW_LOADER_COMPRESS_XZ
901 if (ret == -ENOENT && nondirect)
902 ret = fw_get_filesystem_firmware(device, fw->priv, ".xz",
903 fw_decompress_xz);
904 #endif
905 if (ret == -ENOENT && nondirect)
906 ret = firmware_fallback_platform(fw->priv);
907
908 if (ret) {
909 if (!(opt_flags & FW_OPT_NO_WARN))
910 dev_warn(device,
911 "Direct firmware load for %s failed with error %d\n",
912 name, ret);
913 if (nondirect)
914 ret = firmware_fallback_sysfs(fw, name, device,
915 opt_flags, ret);
916 } else
917 ret = assign_fw(fw, device);
918
919 revert_creds(old_cred);
920 put_cred(kern_cred);
921
922 out:
923 if (ret < 0) {
924 fw_abort_batch_reqs(fw);
925 release_firmware(fw);
926 fw = NULL;
927 } else {
928 fw_log_firmware_info(fw, name, device);
929 }
930
931 *firmware_p = fw;
932 return ret;
933 }
934
935 /**
936 * request_firmware() - send firmware request and wait for it
937 * @firmware_p: pointer to firmware image
938 * @name: name of firmware file
939 * @device: device for which firmware is being loaded
940 *
941 * @firmware_p will be used to return a firmware image by the name
942 * of @name for device @device.
943 *
944 * Should be called from user context where sleeping is allowed.
945 *
946 * @name will be used as $FIRMWARE in the uevent environment and
947 * should be distinctive enough not to be confused with any other
948 * firmware image for this or any other device.
949 *
950 * Caller must hold the reference count of @device.
951 *
952 * The function can be called safely inside device's suspend and
953 * resume callback.
954 **/
955 int
request_firmware(const struct firmware ** firmware_p,const char * name,struct device * device)956 request_firmware(const struct firmware **firmware_p, const char *name,
957 struct device *device)
958 {
959 int ret;
960
961 /* Need to pin this module until return */
962 __module_get(THIS_MODULE);
963 ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
964 FW_OPT_UEVENT);
965 module_put(THIS_MODULE);
966 return ret;
967 }
968 EXPORT_SYMBOL(request_firmware);
969
970 /**
971 * firmware_request_nowarn() - request for an optional fw module
972 * @firmware: pointer to firmware image
973 * @name: name of firmware file
974 * @device: device for which firmware is being loaded
975 *
976 * This function is similar in behaviour to request_firmware(), except it
977 * doesn't produce warning messages when the file is not found. The sysfs
978 * fallback mechanism is enabled if direct filesystem lookup fails. However,
979 * failures to find the firmware file with it are still suppressed. It is
980 * therefore up to the driver to check for the return value of this call and to
981 * decide when to inform the users of errors.
982 **/
firmware_request_nowarn(const struct firmware ** firmware,const char * name,struct device * device)983 int firmware_request_nowarn(const struct firmware **firmware, const char *name,
984 struct device *device)
985 {
986 int ret;
987
988 /* Need to pin this module until return */
989 __module_get(THIS_MODULE);
990 ret = _request_firmware(firmware, name, device, NULL, 0, 0,
991 FW_OPT_UEVENT | FW_OPT_NO_WARN);
992 module_put(THIS_MODULE);
993 return ret;
994 }
995 EXPORT_SYMBOL_GPL(firmware_request_nowarn);
996
997 /**
998 * request_firmware_direct() - load firmware directly without usermode helper
999 * @firmware_p: pointer to firmware image
1000 * @name: name of firmware file
1001 * @device: device for which firmware is being loaded
1002 *
1003 * This function works pretty much like request_firmware(), but this doesn't
1004 * fall back to usermode helper even if the firmware couldn't be loaded
1005 * directly from fs. Hence it's useful for loading optional firmwares, which
1006 * aren't always present, without extra long timeouts of udev.
1007 **/
request_firmware_direct(const struct firmware ** firmware_p,const char * name,struct device * device)1008 int request_firmware_direct(const struct firmware **firmware_p,
1009 const char *name, struct device *device)
1010 {
1011 int ret;
1012
1013 __module_get(THIS_MODULE);
1014 ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
1015 FW_OPT_UEVENT | FW_OPT_NO_WARN |
1016 FW_OPT_NOFALLBACK_SYSFS);
1017 module_put(THIS_MODULE);
1018 return ret;
1019 }
1020 EXPORT_SYMBOL_GPL(request_firmware_direct);
1021
1022 /**
1023 * firmware_request_platform() - request firmware with platform-fw fallback
1024 * @firmware: pointer to firmware image
1025 * @name: name of firmware file
1026 * @device: device for which firmware is being loaded
1027 *
1028 * This function is similar in behaviour to request_firmware, except that if
1029 * direct filesystem lookup fails, it will fallback to looking for a copy of the
1030 * requested firmware embedded in the platform's main (e.g. UEFI) firmware.
1031 **/
firmware_request_platform(const struct firmware ** firmware,const char * name,struct device * device)1032 int firmware_request_platform(const struct firmware **firmware,
1033 const char *name, struct device *device)
1034 {
1035 int ret;
1036
1037 /* Need to pin this module until return */
1038 __module_get(THIS_MODULE);
1039 ret = _request_firmware(firmware, name, device, NULL, 0, 0,
1040 FW_OPT_UEVENT | FW_OPT_FALLBACK_PLATFORM);
1041 module_put(THIS_MODULE);
1042 return ret;
1043 }
1044 EXPORT_SYMBOL_GPL(firmware_request_platform);
1045
1046 /**
1047 * firmware_request_cache() - cache firmware for suspend so resume can use it
1048 * @name: name of firmware file
1049 * @device: device for which firmware should be cached for
1050 *
1051 * There are some devices with an optimization that enables the device to not
1052 * require loading firmware on system reboot. This optimization may still
1053 * require the firmware present on resume from suspend. This routine can be
1054 * used to ensure the firmware is present on resume from suspend in these
1055 * situations. This helper is not compatible with drivers which use
1056 * request_firmware_into_buf() or request_firmware_nowait() with no uevent set.
1057 **/
firmware_request_cache(struct device * device,const char * name)1058 int firmware_request_cache(struct device *device, const char *name)
1059 {
1060 int ret;
1061
1062 mutex_lock(&fw_lock);
1063 ret = fw_add_devm_name(device, name);
1064 mutex_unlock(&fw_lock);
1065
1066 return ret;
1067 }
1068 EXPORT_SYMBOL_GPL(firmware_request_cache);
1069
1070 /**
1071 * request_firmware_into_buf() - load firmware into a previously allocated buffer
1072 * @firmware_p: pointer to firmware image
1073 * @name: name of firmware file
1074 * @device: device for which firmware is being loaded and DMA region allocated
1075 * @buf: address of buffer to load firmware into
1076 * @size: size of buffer
1077 *
1078 * This function works pretty much like request_firmware(), but it doesn't
1079 * allocate a buffer to hold the firmware data. Instead, the firmware
1080 * is loaded directly into the buffer pointed to by @buf and the @firmware_p
1081 * data member is pointed at @buf.
1082 *
1083 * This function doesn't cache firmware either.
1084 */
1085 int
request_firmware_into_buf(const struct firmware ** firmware_p,const char * name,struct device * device,void * buf,size_t size)1086 request_firmware_into_buf(const struct firmware **firmware_p, const char *name,
1087 struct device *device, void *buf, size_t size)
1088 {
1089 int ret;
1090
1091 if (fw_cache_is_setup(device, name))
1092 return -EOPNOTSUPP;
1093
1094 __module_get(THIS_MODULE);
1095 ret = _request_firmware(firmware_p, name, device, buf, size, 0,
1096 FW_OPT_UEVENT | FW_OPT_NOCACHE);
1097 module_put(THIS_MODULE);
1098 return ret;
1099 }
1100 EXPORT_SYMBOL(request_firmware_into_buf);
1101
1102 /**
1103 * request_partial_firmware_into_buf() - load partial firmware into a previously allocated buffer
1104 * @firmware_p: pointer to firmware image
1105 * @name: name of firmware file
1106 * @device: device for which firmware is being loaded and DMA region allocated
1107 * @buf: address of buffer to load firmware into
1108 * @size: size of buffer
1109 * @offset: offset into file to read
1110 *
1111 * This function works pretty much like request_firmware_into_buf except
1112 * it allows a partial read of the file.
1113 */
1114 int
request_partial_firmware_into_buf(const struct firmware ** firmware_p,const char * name,struct device * device,void * buf,size_t size,size_t offset)1115 request_partial_firmware_into_buf(const struct firmware **firmware_p,
1116 const char *name, struct device *device,
1117 void *buf, size_t size, size_t offset)
1118 {
1119 int ret;
1120
1121 if (fw_cache_is_setup(device, name))
1122 return -EOPNOTSUPP;
1123
1124 __module_get(THIS_MODULE);
1125 ret = _request_firmware(firmware_p, name, device, buf, size, offset,
1126 FW_OPT_UEVENT | FW_OPT_NOCACHE |
1127 FW_OPT_PARTIAL);
1128 module_put(THIS_MODULE);
1129 return ret;
1130 }
1131 EXPORT_SYMBOL(request_partial_firmware_into_buf);
1132
1133 /**
1134 * release_firmware() - release the resource associated with a firmware image
1135 * @fw: firmware resource to release
1136 **/
release_firmware(const struct firmware * fw)1137 void release_firmware(const struct firmware *fw)
1138 {
1139 if (fw) {
1140 if (!firmware_is_builtin(fw))
1141 firmware_free_data(fw);
1142 kfree(fw);
1143 }
1144 }
1145 EXPORT_SYMBOL(release_firmware);
1146
1147 /* Async support */
1148 struct firmware_work {
1149 struct work_struct work;
1150 struct module *module;
1151 const char *name;
1152 struct device *device;
1153 void *context;
1154 void (*cont)(const struct firmware *fw, void *context);
1155 u32 opt_flags;
1156 };
1157
request_firmware_work_func(struct work_struct * work)1158 static void request_firmware_work_func(struct work_struct *work)
1159 {
1160 struct firmware_work *fw_work;
1161 const struct firmware *fw;
1162
1163 fw_work = container_of(work, struct firmware_work, work);
1164
1165 _request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0, 0,
1166 fw_work->opt_flags);
1167 fw_work->cont(fw, fw_work->context);
1168 put_device(fw_work->device); /* taken in request_firmware_nowait() */
1169
1170 module_put(fw_work->module);
1171 kfree_const(fw_work->name);
1172 kfree(fw_work);
1173 }
1174
1175 /**
1176 * request_firmware_nowait() - asynchronous version of request_firmware
1177 * @module: module requesting the firmware
1178 * @uevent: sends uevent to copy the firmware image if this flag
1179 * is non-zero else the firmware copy must be done manually.
1180 * @name: name of firmware file
1181 * @device: device for which firmware is being loaded
1182 * @gfp: allocation flags
1183 * @context: will be passed over to @cont, and
1184 * @fw may be %NULL if firmware request fails.
1185 * @cont: function will be called asynchronously when the firmware
1186 * request is over.
1187 *
1188 * Caller must hold the reference count of @device.
1189 *
1190 * Asynchronous variant of request_firmware() for user contexts:
1191 * - sleep for as small periods as possible since it may
1192 * increase kernel boot time of built-in device drivers
1193 * requesting firmware in their ->probe() methods, if
1194 * @gfp is GFP_KERNEL.
1195 *
1196 * - can't sleep at all if @gfp is GFP_ATOMIC.
1197 **/
1198 int
request_firmware_nowait(struct module * module,bool uevent,const char * name,struct device * device,gfp_t gfp,void * context,void (* cont)(const struct firmware * fw,void * context))1199 request_firmware_nowait(
1200 struct module *module, bool uevent,
1201 const char *name, struct device *device, gfp_t gfp, void *context,
1202 void (*cont)(const struct firmware *fw, void *context))
1203 {
1204 struct firmware_work *fw_work;
1205
1206 fw_work = kzalloc(sizeof(struct firmware_work), gfp);
1207 if (!fw_work)
1208 return -ENOMEM;
1209
1210 fw_work->module = module;
1211 fw_work->name = kstrdup_const(name, gfp);
1212 if (!fw_work->name) {
1213 kfree(fw_work);
1214 return -ENOMEM;
1215 }
1216 fw_work->device = device;
1217 fw_work->context = context;
1218 fw_work->cont = cont;
1219 fw_work->opt_flags = FW_OPT_NOWAIT |
1220 (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
1221
1222 if (!uevent && fw_cache_is_setup(device, name)) {
1223 kfree_const(fw_work->name);
1224 kfree(fw_work);
1225 return -EOPNOTSUPP;
1226 }
1227
1228 if (!try_module_get(module)) {
1229 kfree_const(fw_work->name);
1230 kfree(fw_work);
1231 return -EFAULT;
1232 }
1233
1234 get_device(fw_work->device);
1235 INIT_WORK(&fw_work->work, request_firmware_work_func);
1236 schedule_work(&fw_work->work);
1237 return 0;
1238 }
1239 EXPORT_SYMBOL(request_firmware_nowait);
1240
1241 #ifdef CONFIG_FW_CACHE
1242 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1243
1244 /**
1245 * cache_firmware() - cache one firmware image in kernel memory space
1246 * @fw_name: the firmware image name
1247 *
1248 * Cache firmware in kernel memory so that drivers can use it when
1249 * system isn't ready for them to request firmware image from userspace.
1250 * Once it returns successfully, driver can use request_firmware or its
1251 * nowait version to get the cached firmware without any interacting
1252 * with userspace
1253 *
1254 * Return 0 if the firmware image has been cached successfully
1255 * Return !0 otherwise
1256 *
1257 */
cache_firmware(const char * fw_name)1258 static int cache_firmware(const char *fw_name)
1259 {
1260 int ret;
1261 const struct firmware *fw;
1262
1263 pr_debug("%s: %s\n", __func__, fw_name);
1264
1265 ret = request_firmware(&fw, fw_name, NULL);
1266 if (!ret)
1267 kfree(fw);
1268
1269 pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1270
1271 return ret;
1272 }
1273
lookup_fw_priv(const char * fw_name)1274 static struct fw_priv *lookup_fw_priv(const char *fw_name)
1275 {
1276 struct fw_priv *tmp;
1277 struct firmware_cache *fwc = &fw_cache;
1278
1279 spin_lock(&fwc->lock);
1280 tmp = __lookup_fw_priv(fw_name);
1281 spin_unlock(&fwc->lock);
1282
1283 return tmp;
1284 }
1285
1286 /**
1287 * uncache_firmware() - remove one cached firmware image
1288 * @fw_name: the firmware image name
1289 *
1290 * Uncache one firmware image which has been cached successfully
1291 * before.
1292 *
1293 * Return 0 if the firmware cache has been removed successfully
1294 * Return !0 otherwise
1295 *
1296 */
uncache_firmware(const char * fw_name)1297 static int uncache_firmware(const char *fw_name)
1298 {
1299 struct fw_priv *fw_priv;
1300 struct firmware fw;
1301
1302 pr_debug("%s: %s\n", __func__, fw_name);
1303
1304 if (firmware_request_builtin(&fw, fw_name))
1305 return 0;
1306
1307 fw_priv = lookup_fw_priv(fw_name);
1308 if (fw_priv) {
1309 free_fw_priv(fw_priv);
1310 return 0;
1311 }
1312
1313 return -EINVAL;
1314 }
1315
alloc_fw_cache_entry(const char * name)1316 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1317 {
1318 struct fw_cache_entry *fce;
1319
1320 fce = kzalloc(sizeof(*fce), GFP_ATOMIC);
1321 if (!fce)
1322 goto exit;
1323
1324 fce->name = kstrdup_const(name, GFP_ATOMIC);
1325 if (!fce->name) {
1326 kfree(fce);
1327 fce = NULL;
1328 goto exit;
1329 }
1330 exit:
1331 return fce;
1332 }
1333
__fw_entry_found(const char * name)1334 static int __fw_entry_found(const char *name)
1335 {
1336 struct firmware_cache *fwc = &fw_cache;
1337 struct fw_cache_entry *fce;
1338
1339 list_for_each_entry(fce, &fwc->fw_names, list) {
1340 if (!strcmp(fce->name, name))
1341 return 1;
1342 }
1343 return 0;
1344 }
1345
fw_cache_piggyback_on_request(struct fw_priv * fw_priv)1346 static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv)
1347 {
1348 const char *name = fw_priv->fw_name;
1349 struct firmware_cache *fwc = fw_priv->fwc;
1350 struct fw_cache_entry *fce;
1351
1352 spin_lock(&fwc->name_lock);
1353 if (__fw_entry_found(name))
1354 goto found;
1355
1356 fce = alloc_fw_cache_entry(name);
1357 if (fce) {
1358 list_add(&fce->list, &fwc->fw_names);
1359 kref_get(&fw_priv->ref);
1360 pr_debug("%s: fw: %s\n", __func__, name);
1361 }
1362 found:
1363 spin_unlock(&fwc->name_lock);
1364 }
1365
free_fw_cache_entry(struct fw_cache_entry * fce)1366 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1367 {
1368 kfree_const(fce->name);
1369 kfree(fce);
1370 }
1371
__async_dev_cache_fw_image(void * fw_entry,async_cookie_t cookie)1372 static void __async_dev_cache_fw_image(void *fw_entry,
1373 async_cookie_t cookie)
1374 {
1375 struct fw_cache_entry *fce = fw_entry;
1376 struct firmware_cache *fwc = &fw_cache;
1377 int ret;
1378
1379 ret = cache_firmware(fce->name);
1380 if (ret) {
1381 spin_lock(&fwc->name_lock);
1382 list_del(&fce->list);
1383 spin_unlock(&fwc->name_lock);
1384
1385 free_fw_cache_entry(fce);
1386 }
1387 }
1388
1389 /* called with dev->devres_lock held */
dev_create_fw_entry(struct device * dev,void * res,void * data)1390 static void dev_create_fw_entry(struct device *dev, void *res,
1391 void *data)
1392 {
1393 struct fw_name_devm *fwn = res;
1394 const char *fw_name = fwn->name;
1395 struct list_head *head = data;
1396 struct fw_cache_entry *fce;
1397
1398 fce = alloc_fw_cache_entry(fw_name);
1399 if (fce)
1400 list_add(&fce->list, head);
1401 }
1402
devm_name_match(struct device * dev,void * res,void * match_data)1403 static int devm_name_match(struct device *dev, void *res,
1404 void *match_data)
1405 {
1406 struct fw_name_devm *fwn = res;
1407 return (fwn->magic == (unsigned long)match_data);
1408 }
1409
dev_cache_fw_image(struct device * dev,void * data)1410 static void dev_cache_fw_image(struct device *dev, void *data)
1411 {
1412 LIST_HEAD(todo);
1413 struct fw_cache_entry *fce;
1414 struct fw_cache_entry *fce_next;
1415 struct firmware_cache *fwc = &fw_cache;
1416
1417 devres_for_each_res(dev, fw_name_devm_release,
1418 devm_name_match, &fw_cache,
1419 dev_create_fw_entry, &todo);
1420
1421 list_for_each_entry_safe(fce, fce_next, &todo, list) {
1422 list_del(&fce->list);
1423
1424 spin_lock(&fwc->name_lock);
1425 /* only one cache entry for one firmware */
1426 if (!__fw_entry_found(fce->name)) {
1427 list_add(&fce->list, &fwc->fw_names);
1428 } else {
1429 free_fw_cache_entry(fce);
1430 fce = NULL;
1431 }
1432 spin_unlock(&fwc->name_lock);
1433
1434 if (fce)
1435 async_schedule_domain(__async_dev_cache_fw_image,
1436 (void *)fce,
1437 &fw_cache_domain);
1438 }
1439 }
1440
__device_uncache_fw_images(void)1441 static void __device_uncache_fw_images(void)
1442 {
1443 struct firmware_cache *fwc = &fw_cache;
1444 struct fw_cache_entry *fce;
1445
1446 spin_lock(&fwc->name_lock);
1447 while (!list_empty(&fwc->fw_names)) {
1448 fce = list_entry(fwc->fw_names.next,
1449 struct fw_cache_entry, list);
1450 list_del(&fce->list);
1451 spin_unlock(&fwc->name_lock);
1452
1453 uncache_firmware(fce->name);
1454 free_fw_cache_entry(fce);
1455
1456 spin_lock(&fwc->name_lock);
1457 }
1458 spin_unlock(&fwc->name_lock);
1459 }
1460
1461 /**
1462 * device_cache_fw_images() - cache devices' firmware
1463 *
1464 * If one device called request_firmware or its nowait version
1465 * successfully before, the firmware names are recored into the
1466 * device's devres link list, so device_cache_fw_images can call
1467 * cache_firmware() to cache these firmwares for the device,
1468 * then the device driver can load its firmwares easily at
1469 * time when system is not ready to complete loading firmware.
1470 */
device_cache_fw_images(void)1471 static void device_cache_fw_images(void)
1472 {
1473 struct firmware_cache *fwc = &fw_cache;
1474 DEFINE_WAIT(wait);
1475
1476 pr_debug("%s\n", __func__);
1477
1478 /* cancel uncache work */
1479 cancel_delayed_work_sync(&fwc->work);
1480
1481 fw_fallback_set_cache_timeout();
1482
1483 mutex_lock(&fw_lock);
1484 fwc->state = FW_LOADER_START_CACHE;
1485 dpm_for_each_dev(NULL, dev_cache_fw_image);
1486 mutex_unlock(&fw_lock);
1487
1488 /* wait for completion of caching firmware for all devices */
1489 async_synchronize_full_domain(&fw_cache_domain);
1490
1491 fw_fallback_set_default_timeout();
1492 }
1493
1494 /**
1495 * device_uncache_fw_images() - uncache devices' firmware
1496 *
1497 * uncache all firmwares which have been cached successfully
1498 * by device_uncache_fw_images earlier
1499 */
device_uncache_fw_images(void)1500 static void device_uncache_fw_images(void)
1501 {
1502 pr_debug("%s\n", __func__);
1503 __device_uncache_fw_images();
1504 }
1505
device_uncache_fw_images_work(struct work_struct * work)1506 static void device_uncache_fw_images_work(struct work_struct *work)
1507 {
1508 device_uncache_fw_images();
1509 }
1510
1511 /**
1512 * device_uncache_fw_images_delay() - uncache devices firmwares
1513 * @delay: number of milliseconds to delay uncache device firmwares
1514 *
1515 * uncache all devices's firmwares which has been cached successfully
1516 * by device_cache_fw_images after @delay milliseconds.
1517 */
device_uncache_fw_images_delay(unsigned long delay)1518 static void device_uncache_fw_images_delay(unsigned long delay)
1519 {
1520 queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1521 msecs_to_jiffies(delay));
1522 }
1523
fw_pm_notify(struct notifier_block * notify_block,unsigned long mode,void * unused)1524 static int fw_pm_notify(struct notifier_block *notify_block,
1525 unsigned long mode, void *unused)
1526 {
1527 switch (mode) {
1528 case PM_HIBERNATION_PREPARE:
1529 case PM_SUSPEND_PREPARE:
1530 case PM_RESTORE_PREPARE:
1531 /*
1532 * Here, kill pending fallback requests will only kill
1533 * non-uevent firmware request to avoid stalling suspend.
1534 */
1535 kill_pending_fw_fallback_reqs(false);
1536 device_cache_fw_images();
1537 break;
1538
1539 case PM_POST_SUSPEND:
1540 case PM_POST_HIBERNATION:
1541 case PM_POST_RESTORE:
1542 /*
1543 * In case that system sleep failed and syscore_suspend is
1544 * not called.
1545 */
1546 mutex_lock(&fw_lock);
1547 fw_cache.state = FW_LOADER_NO_CACHE;
1548 mutex_unlock(&fw_lock);
1549
1550 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1551 break;
1552 }
1553
1554 return 0;
1555 }
1556
1557 /* stop caching firmware once syscore_suspend is reached */
fw_suspend(void)1558 static int fw_suspend(void)
1559 {
1560 fw_cache.state = FW_LOADER_NO_CACHE;
1561 return 0;
1562 }
1563
1564 static struct syscore_ops fw_syscore_ops = {
1565 .suspend = fw_suspend,
1566 };
1567
register_fw_pm_ops(void)1568 static int __init register_fw_pm_ops(void)
1569 {
1570 int ret;
1571
1572 spin_lock_init(&fw_cache.name_lock);
1573 INIT_LIST_HEAD(&fw_cache.fw_names);
1574
1575 INIT_DELAYED_WORK(&fw_cache.work,
1576 device_uncache_fw_images_work);
1577
1578 fw_cache.pm_notify.notifier_call = fw_pm_notify;
1579 ret = register_pm_notifier(&fw_cache.pm_notify);
1580 if (ret)
1581 return ret;
1582
1583 register_syscore_ops(&fw_syscore_ops);
1584
1585 return ret;
1586 }
1587
unregister_fw_pm_ops(void)1588 static inline void unregister_fw_pm_ops(void)
1589 {
1590 unregister_syscore_ops(&fw_syscore_ops);
1591 unregister_pm_notifier(&fw_cache.pm_notify);
1592 }
1593 #else
fw_cache_piggyback_on_request(struct fw_priv * fw_priv)1594 static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv)
1595 {
1596 }
register_fw_pm_ops(void)1597 static inline int register_fw_pm_ops(void)
1598 {
1599 return 0;
1600 }
unregister_fw_pm_ops(void)1601 static inline void unregister_fw_pm_ops(void)
1602 {
1603 }
1604 #endif
1605
fw_cache_init(void)1606 static void __init fw_cache_init(void)
1607 {
1608 spin_lock_init(&fw_cache.lock);
1609 INIT_LIST_HEAD(&fw_cache.head);
1610 fw_cache.state = FW_LOADER_NO_CACHE;
1611 }
1612
fw_shutdown_notify(struct notifier_block * unused1,unsigned long unused2,void * unused3)1613 static int fw_shutdown_notify(struct notifier_block *unused1,
1614 unsigned long unused2, void *unused3)
1615 {
1616 /*
1617 * Kill all pending fallback requests to avoid both stalling shutdown,
1618 * and avoid a deadlock with the usermode_lock.
1619 */
1620 kill_pending_fw_fallback_reqs(true);
1621
1622 return NOTIFY_DONE;
1623 }
1624
1625 static struct notifier_block fw_shutdown_nb = {
1626 .notifier_call = fw_shutdown_notify,
1627 };
1628
firmware_class_init(void)1629 static int __init firmware_class_init(void)
1630 {
1631 int ret;
1632
1633 /* No need to unfold these on exit */
1634 fw_cache_init();
1635
1636 ret = register_fw_pm_ops();
1637 if (ret)
1638 return ret;
1639
1640 ret = register_reboot_notifier(&fw_shutdown_nb);
1641 if (ret)
1642 goto out;
1643
1644 return register_sysfs_loader();
1645
1646 out:
1647 unregister_fw_pm_ops();
1648 return ret;
1649 }
1650
firmware_class_exit(void)1651 static void __exit firmware_class_exit(void)
1652 {
1653 unregister_fw_pm_ops();
1654 unregister_reboot_notifier(&fw_shutdown_nb);
1655 unregister_sysfs_loader();
1656 }
1657
1658 fs_initcall(firmware_class_init);
1659 module_exit(firmware_class_exit);
1660