1 /*
2 * firmware_class.c - Multi purpose firmware loading support
3 *
4 * Copyright (c) 2003 Manuel Estrada Sainz
5 *
6 * Please see Documentation/firmware_class/ for more information.
7 *
8 */
9
10 #include <linux/capability.h>
11 #include <linux/device.h>
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/timer.h>
15 #include <linux/vmalloc.h>
16 #include <linux/interrupt.h>
17 #include <linux/bitops.h>
18 #include <linux/mutex.h>
19 #include <linux/workqueue.h>
20 #include <linux/highmem.h>
21 #include <linux/firmware.h>
22 #include <linux/slab.h>
23 #include <linux/sched.h>
24 #include <linux/file.h>
25 #include <linux/list.h>
26 #include <linux/async.h>
27 #include <linux/pm.h>
28 #include <linux/suspend.h>
29 #include <linux/syscore_ops.h>
30 #include <linux/reboot.h>
31 #include <linux/security.h>
32
33 #include <generated/utsrelease.h>
34
35 #include "base.h"
36
37 MODULE_AUTHOR("Manuel Estrada Sainz");
38 MODULE_DESCRIPTION("Multi purpose firmware loading support");
39 MODULE_LICENSE("GPL");
40
41 /* Builtin firmware support */
42
43 #ifdef CONFIG_FW_LOADER
44
45 extern struct builtin_fw __start_builtin_fw[];
46 extern struct builtin_fw __end_builtin_fw[];
47
fw_get_builtin_firmware(struct firmware * fw,const char * name)48 static bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
49 {
50 struct builtin_fw *b_fw;
51
52 for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
53 if (strcmp(name, b_fw->name) == 0) {
54 fw->size = b_fw->size;
55 fw->data = b_fw->data;
56 return true;
57 }
58 }
59
60 return false;
61 }
62
fw_is_builtin_firmware(const struct firmware * fw)63 static bool fw_is_builtin_firmware(const struct firmware *fw)
64 {
65 struct builtin_fw *b_fw;
66
67 for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
68 if (fw->data == b_fw->data)
69 return true;
70
71 return false;
72 }
73
74 #else /* Module case - no builtin firmware support */
75
fw_get_builtin_firmware(struct firmware * fw,const char * name)76 static inline bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
77 {
78 return false;
79 }
80
fw_is_builtin_firmware(const struct firmware * fw)81 static inline bool fw_is_builtin_firmware(const struct firmware *fw)
82 {
83 return false;
84 }
85 #endif
86
87 enum {
88 FW_STATUS_LOADING,
89 FW_STATUS_DONE,
90 FW_STATUS_ABORT,
91 };
92
93 static int loading_timeout = 60; /* In seconds */
94
firmware_loading_timeout(void)95 static inline long firmware_loading_timeout(void)
96 {
97 return loading_timeout > 0 ? loading_timeout * HZ : MAX_JIFFY_OFFSET;
98 }
99
100 /* firmware behavior options */
101 #define FW_OPT_UEVENT (1U << 0)
102 #define FW_OPT_NOWAIT (1U << 1)
103 #ifdef CONFIG_FW_LOADER_USER_HELPER
104 #define FW_OPT_USERHELPER (1U << 2)
105 #else
106 #define FW_OPT_USERHELPER 0
107 #endif
108 #ifdef CONFIG_FW_LOADER_USER_HELPER_FALLBACK
109 #define FW_OPT_FALLBACK FW_OPT_USERHELPER
110 #else
111 #define FW_OPT_FALLBACK 0
112 #endif
113 #define FW_OPT_NO_WARN (1U << 3)
114
115 struct firmware_cache {
116 /* firmware_buf instance will be added into the below list */
117 spinlock_t lock;
118 struct list_head head;
119 int state;
120
121 #ifdef CONFIG_PM_SLEEP
122 /*
123 * Names of firmware images which have been cached successfully
124 * will be added into the below list so that device uncache
125 * helper can trace which firmware images have been cached
126 * before.
127 */
128 spinlock_t name_lock;
129 struct list_head fw_names;
130
131 struct delayed_work work;
132
133 struct notifier_block pm_notify;
134 #endif
135 };
136
137 struct firmware_buf {
138 struct kref ref;
139 struct list_head list;
140 struct completion completion;
141 struct firmware_cache *fwc;
142 unsigned long status;
143 void *data;
144 size_t size;
145 #ifdef CONFIG_FW_LOADER_USER_HELPER
146 bool is_paged_buf;
147 bool need_uevent;
148 struct page **pages;
149 int nr_pages;
150 int page_array_size;
151 struct list_head pending_list;
152 #endif
153 char fw_id[];
154 };
155
156 struct fw_cache_entry {
157 struct list_head list;
158 char name[];
159 };
160
161 struct fw_name_devm {
162 unsigned long magic;
163 char name[];
164 };
165
166 #define to_fwbuf(d) container_of(d, struct firmware_buf, ref)
167
168 #define FW_LOADER_NO_CACHE 0
169 #define FW_LOADER_START_CACHE 1
170
171 static int fw_cache_piggyback_on_request(const char *name);
172
173 /* fw_lock could be moved to 'struct firmware_priv' but since it is just
174 * guarding for corner cases a global lock should be OK */
175 static DEFINE_MUTEX(fw_lock);
176
177 static struct firmware_cache fw_cache;
178
__allocate_fw_buf(const char * fw_name,struct firmware_cache * fwc)179 static struct firmware_buf *__allocate_fw_buf(const char *fw_name,
180 struct firmware_cache *fwc)
181 {
182 struct firmware_buf *buf;
183
184 buf = kzalloc(sizeof(*buf) + strlen(fw_name) + 1, GFP_ATOMIC);
185
186 if (!buf)
187 return buf;
188
189 kref_init(&buf->ref);
190 strcpy(buf->fw_id, fw_name);
191 buf->fwc = fwc;
192 init_completion(&buf->completion);
193 #ifdef CONFIG_FW_LOADER_USER_HELPER
194 INIT_LIST_HEAD(&buf->pending_list);
195 #endif
196
197 pr_debug("%s: fw-%s buf=%p\n", __func__, fw_name, buf);
198
199 return buf;
200 }
201
__fw_lookup_buf(const char * fw_name)202 static struct firmware_buf *__fw_lookup_buf(const char *fw_name)
203 {
204 struct firmware_buf *tmp;
205 struct firmware_cache *fwc = &fw_cache;
206
207 list_for_each_entry(tmp, &fwc->head, list)
208 if (!strcmp(tmp->fw_id, fw_name))
209 return tmp;
210 return NULL;
211 }
212
fw_lookup_and_allocate_buf(const char * fw_name,struct firmware_cache * fwc,struct firmware_buf ** buf)213 static int fw_lookup_and_allocate_buf(const char *fw_name,
214 struct firmware_cache *fwc,
215 struct firmware_buf **buf)
216 {
217 struct firmware_buf *tmp;
218
219 spin_lock(&fwc->lock);
220 tmp = __fw_lookup_buf(fw_name);
221 if (tmp) {
222 kref_get(&tmp->ref);
223 spin_unlock(&fwc->lock);
224 *buf = tmp;
225 return 1;
226 }
227 tmp = __allocate_fw_buf(fw_name, fwc);
228 if (tmp)
229 list_add(&tmp->list, &fwc->head);
230 spin_unlock(&fwc->lock);
231
232 *buf = tmp;
233
234 return tmp ? 0 : -ENOMEM;
235 }
236
__fw_free_buf(struct kref * ref)237 static void __fw_free_buf(struct kref *ref)
238 __releases(&fwc->lock)
239 {
240 struct firmware_buf *buf = to_fwbuf(ref);
241 struct firmware_cache *fwc = buf->fwc;
242
243 pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
244 __func__, buf->fw_id, buf, buf->data,
245 (unsigned int)buf->size);
246
247 list_del(&buf->list);
248 spin_unlock(&fwc->lock);
249
250 #ifdef CONFIG_FW_LOADER_USER_HELPER
251 if (buf->is_paged_buf) {
252 int i;
253 vunmap(buf->data);
254 for (i = 0; i < buf->nr_pages; i++)
255 __free_page(buf->pages[i]);
256 kfree(buf->pages);
257 } else
258 #endif
259 vfree(buf->data);
260 kfree(buf);
261 }
262
fw_free_buf(struct firmware_buf * buf)263 static void fw_free_buf(struct firmware_buf *buf)
264 {
265 struct firmware_cache *fwc = buf->fwc;
266 spin_lock(&fwc->lock);
267 if (!kref_put(&buf->ref, __fw_free_buf))
268 spin_unlock(&fwc->lock);
269 }
270
271 /* direct firmware loading support */
272 static char fw_path_para[256];
273 static const char * const fw_path[] = {
274 fw_path_para,
275 "/lib/firmware/updates/" UTS_RELEASE,
276 "/lib/firmware/updates",
277 "/lib/firmware/" UTS_RELEASE,
278 "/lib/firmware"
279 };
280
281 /*
282 * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
283 * from kernel command line because firmware_class is generally built in
284 * kernel instead of module.
285 */
286 module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
287 MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
288
fw_read_file_contents(struct file * file,struct firmware_buf * fw_buf)289 static int fw_read_file_contents(struct file *file, struct firmware_buf *fw_buf)
290 {
291 int size;
292 char *buf;
293 int rc;
294
295 if (!S_ISREG(file_inode(file)->i_mode))
296 return -EINVAL;
297 size = i_size_read(file_inode(file));
298 if (size <= 0)
299 return -EINVAL;
300 buf = vmalloc(size);
301 if (!buf)
302 return -ENOMEM;
303 rc = kernel_read(file, 0, buf, size);
304 if (rc != size) {
305 if (rc > 0)
306 rc = -EIO;
307 goto fail;
308 }
309 rc = security_kernel_fw_from_file(file, buf, size);
310 if (rc)
311 goto fail;
312 fw_buf->data = buf;
313 fw_buf->size = size;
314 return 0;
315 fail:
316 vfree(buf);
317 return rc;
318 }
319
fw_get_filesystem_firmware(struct device * device,struct firmware_buf * buf)320 static int fw_get_filesystem_firmware(struct device *device,
321 struct firmware_buf *buf)
322 {
323 int i;
324 int rc = -ENOENT;
325 char *path = __getname();
326
327 for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
328 struct file *file;
329
330 /* skip the unset customized path */
331 if (!fw_path[i][0])
332 continue;
333
334 snprintf(path, PATH_MAX, "%s/%s", fw_path[i], buf->fw_id);
335
336 file = filp_open(path, O_RDONLY, 0);
337 if (IS_ERR(file))
338 continue;
339 rc = fw_read_file_contents(file, buf);
340 fput(file);
341 if (rc)
342 dev_warn(device, "firmware, attempted to load %s, but failed with error %d\n",
343 path, rc);
344 else
345 break;
346 }
347 __putname(path);
348
349 if (!rc) {
350 dev_dbg(device, "firmware: direct-loading firmware %s\n",
351 buf->fw_id);
352 mutex_lock(&fw_lock);
353 set_bit(FW_STATUS_DONE, &buf->status);
354 complete_all(&buf->completion);
355 mutex_unlock(&fw_lock);
356 }
357
358 return rc;
359 }
360
361 /* firmware holds the ownership of pages */
firmware_free_data(const struct firmware * fw)362 static void firmware_free_data(const struct firmware *fw)
363 {
364 /* Loaded directly? */
365 if (!fw->priv) {
366 vfree(fw->data);
367 return;
368 }
369 fw_free_buf(fw->priv);
370 }
371
372 /* store the pages buffer info firmware from buf */
fw_set_page_data(struct firmware_buf * buf,struct firmware * fw)373 static void fw_set_page_data(struct firmware_buf *buf, struct firmware *fw)
374 {
375 fw->priv = buf;
376 #ifdef CONFIG_FW_LOADER_USER_HELPER
377 fw->pages = buf->pages;
378 #endif
379 fw->size = buf->size;
380 fw->data = buf->data;
381
382 pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
383 __func__, buf->fw_id, buf, buf->data,
384 (unsigned int)buf->size);
385 }
386
387 #ifdef CONFIG_PM_SLEEP
fw_name_devm_release(struct device * dev,void * res)388 static void fw_name_devm_release(struct device *dev, void *res)
389 {
390 struct fw_name_devm *fwn = res;
391
392 if (fwn->magic == (unsigned long)&fw_cache)
393 pr_debug("%s: fw_name-%s devm-%p released\n",
394 __func__, fwn->name, res);
395 }
396
fw_devm_match(struct device * dev,void * res,void * match_data)397 static int fw_devm_match(struct device *dev, void *res,
398 void *match_data)
399 {
400 struct fw_name_devm *fwn = res;
401
402 return (fwn->magic == (unsigned long)&fw_cache) &&
403 !strcmp(fwn->name, match_data);
404 }
405
fw_find_devm_name(struct device * dev,const char * name)406 static struct fw_name_devm *fw_find_devm_name(struct device *dev,
407 const char *name)
408 {
409 struct fw_name_devm *fwn;
410
411 fwn = devres_find(dev, fw_name_devm_release,
412 fw_devm_match, (void *)name);
413 return fwn;
414 }
415
416 /* add firmware name into devres list */
fw_add_devm_name(struct device * dev,const char * name)417 static int fw_add_devm_name(struct device *dev, const char *name)
418 {
419 struct fw_name_devm *fwn;
420
421 fwn = fw_find_devm_name(dev, name);
422 if (fwn)
423 return 1;
424
425 fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm) +
426 strlen(name) + 1, GFP_KERNEL);
427 if (!fwn)
428 return -ENOMEM;
429
430 fwn->magic = (unsigned long)&fw_cache;
431 strcpy(fwn->name, name);
432 devres_add(dev, fwn);
433
434 return 0;
435 }
436 #else
fw_add_devm_name(struct device * dev,const char * name)437 static int fw_add_devm_name(struct device *dev, const char *name)
438 {
439 return 0;
440 }
441 #endif
442
443
444 /*
445 * user-mode helper code
446 */
447 #ifdef CONFIG_FW_LOADER_USER_HELPER
448 struct firmware_priv {
449 bool nowait;
450 struct device dev;
451 struct firmware_buf *buf;
452 struct firmware *fw;
453 };
454
to_firmware_priv(struct device * dev)455 static struct firmware_priv *to_firmware_priv(struct device *dev)
456 {
457 return container_of(dev, struct firmware_priv, dev);
458 }
459
__fw_load_abort(struct firmware_buf * buf)460 static void __fw_load_abort(struct firmware_buf *buf)
461 {
462 /*
463 * There is a small window in which user can write to 'loading'
464 * between loading done and disappearance of 'loading'
465 */
466 if (test_bit(FW_STATUS_DONE, &buf->status))
467 return;
468
469 list_del_init(&buf->pending_list);
470 set_bit(FW_STATUS_ABORT, &buf->status);
471 complete_all(&buf->completion);
472 }
473
fw_load_abort(struct firmware_priv * fw_priv)474 static void fw_load_abort(struct firmware_priv *fw_priv)
475 {
476 struct firmware_buf *buf = fw_priv->buf;
477
478 __fw_load_abort(buf);
479
480 /* avoid user action after loading abort */
481 fw_priv->buf = NULL;
482 }
483
484 #define is_fw_load_aborted(buf) \
485 test_bit(FW_STATUS_ABORT, &(buf)->status)
486
487 static LIST_HEAD(pending_fw_head);
488
489 /* reboot notifier for avoid deadlock with usermode_lock */
fw_shutdown_notify(struct notifier_block * unused1,unsigned long unused2,void * unused3)490 static int fw_shutdown_notify(struct notifier_block *unused1,
491 unsigned long unused2, void *unused3)
492 {
493 mutex_lock(&fw_lock);
494 while (!list_empty(&pending_fw_head))
495 __fw_load_abort(list_first_entry(&pending_fw_head,
496 struct firmware_buf,
497 pending_list));
498 mutex_unlock(&fw_lock);
499 return NOTIFY_DONE;
500 }
501
502 static struct notifier_block fw_shutdown_nb = {
503 .notifier_call = fw_shutdown_notify,
504 };
505
timeout_show(struct class * class,struct class_attribute * attr,char * buf)506 static ssize_t timeout_show(struct class *class, struct class_attribute *attr,
507 char *buf)
508 {
509 return sprintf(buf, "%d\n", loading_timeout);
510 }
511
512 /**
513 * firmware_timeout_store - set number of seconds to wait for firmware
514 * @class: device class pointer
515 * @attr: device attribute pointer
516 * @buf: buffer to scan for timeout value
517 * @count: number of bytes in @buf
518 *
519 * Sets the number of seconds to wait for the firmware. Once
520 * this expires an error will be returned to the driver and no
521 * firmware will be provided.
522 *
523 * Note: zero means 'wait forever'.
524 **/
timeout_store(struct class * class,struct class_attribute * attr,const char * buf,size_t count)525 static ssize_t timeout_store(struct class *class, struct class_attribute *attr,
526 const char *buf, size_t count)
527 {
528 loading_timeout = simple_strtol(buf, NULL, 10);
529 if (loading_timeout < 0)
530 loading_timeout = 0;
531
532 return count;
533 }
534
535 static struct class_attribute firmware_class_attrs[] = {
536 __ATTR_RW(timeout),
537 __ATTR_NULL
538 };
539
fw_dev_release(struct device * dev)540 static void fw_dev_release(struct device *dev)
541 {
542 struct firmware_priv *fw_priv = to_firmware_priv(dev);
543
544 kfree(fw_priv);
545 }
546
do_firmware_uevent(struct firmware_priv * fw_priv,struct kobj_uevent_env * env)547 static int do_firmware_uevent(struct firmware_priv *fw_priv, struct kobj_uevent_env *env)
548 {
549 if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->buf->fw_id))
550 return -ENOMEM;
551 if (add_uevent_var(env, "TIMEOUT=%i", loading_timeout))
552 return -ENOMEM;
553 if (add_uevent_var(env, "ASYNC=%d", fw_priv->nowait))
554 return -ENOMEM;
555
556 return 0;
557 }
558
firmware_uevent(struct device * dev,struct kobj_uevent_env * env)559 static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
560 {
561 struct firmware_priv *fw_priv = to_firmware_priv(dev);
562 int err = 0;
563
564 mutex_lock(&fw_lock);
565 if (fw_priv->buf)
566 err = do_firmware_uevent(fw_priv, env);
567 mutex_unlock(&fw_lock);
568 return err;
569 }
570
571 static struct class firmware_class = {
572 .name = "firmware",
573 .class_attrs = firmware_class_attrs,
574 .dev_uevent = firmware_uevent,
575 .dev_release = fw_dev_release,
576 };
577
firmware_loading_show(struct device * dev,struct device_attribute * attr,char * buf)578 static ssize_t firmware_loading_show(struct device *dev,
579 struct device_attribute *attr, char *buf)
580 {
581 struct firmware_priv *fw_priv = to_firmware_priv(dev);
582 int loading = 0;
583
584 mutex_lock(&fw_lock);
585 if (fw_priv->buf)
586 loading = test_bit(FW_STATUS_LOADING, &fw_priv->buf->status);
587 mutex_unlock(&fw_lock);
588
589 return sprintf(buf, "%d\n", loading);
590 }
591
592 /* Some architectures don't have PAGE_KERNEL_RO */
593 #ifndef PAGE_KERNEL_RO
594 #define PAGE_KERNEL_RO PAGE_KERNEL
595 #endif
596
597 /* one pages buffer should be mapped/unmapped only once */
fw_map_pages_buf(struct firmware_buf * buf)598 static int fw_map_pages_buf(struct firmware_buf *buf)
599 {
600 if (!buf->is_paged_buf)
601 return 0;
602
603 vunmap(buf->data);
604 buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);
605 if (!buf->data)
606 return -ENOMEM;
607 return 0;
608 }
609
610 /**
611 * firmware_loading_store - set value in the 'loading' control file
612 * @dev: device pointer
613 * @attr: device attribute pointer
614 * @buf: buffer to scan for loading control value
615 * @count: number of bytes in @buf
616 *
617 * The relevant values are:
618 *
619 * 1: Start a load, discarding any previous partial load.
620 * 0: Conclude the load and hand the data to the driver code.
621 * -1: Conclude the load with an error and discard any written data.
622 **/
firmware_loading_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)623 static ssize_t firmware_loading_store(struct device *dev,
624 struct device_attribute *attr,
625 const char *buf, size_t count)
626 {
627 struct firmware_priv *fw_priv = to_firmware_priv(dev);
628 struct firmware_buf *fw_buf;
629 ssize_t written = count;
630 int loading = simple_strtol(buf, NULL, 10);
631 int i;
632
633 mutex_lock(&fw_lock);
634 fw_buf = fw_priv->buf;
635 if (!fw_buf)
636 goto out;
637
638 switch (loading) {
639 case 1:
640 /* discarding any previous partial load */
641 if (!test_bit(FW_STATUS_DONE, &fw_buf->status)) {
642 for (i = 0; i < fw_buf->nr_pages; i++)
643 __free_page(fw_buf->pages[i]);
644 kfree(fw_buf->pages);
645 fw_buf->pages = NULL;
646 fw_buf->page_array_size = 0;
647 fw_buf->nr_pages = 0;
648 set_bit(FW_STATUS_LOADING, &fw_buf->status);
649 }
650 break;
651 case 0:
652 if (test_bit(FW_STATUS_LOADING, &fw_buf->status)) {
653 int rc;
654
655 set_bit(FW_STATUS_DONE, &fw_buf->status);
656 clear_bit(FW_STATUS_LOADING, &fw_buf->status);
657
658 /*
659 * Several loading requests may be pending on
660 * one same firmware buf, so let all requests
661 * see the mapped 'buf->data' once the loading
662 * is completed.
663 * */
664 rc = fw_map_pages_buf(fw_buf);
665 if (rc)
666 dev_err(dev, "%s: map pages failed\n",
667 __func__);
668 else
669 rc = security_kernel_fw_from_file(NULL,
670 fw_buf->data, fw_buf->size);
671
672 /*
673 * Same logic as fw_load_abort, only the DONE bit
674 * is ignored and we set ABORT only on failure.
675 */
676 list_del_init(&fw_buf->pending_list);
677 if (rc) {
678 set_bit(FW_STATUS_ABORT, &fw_buf->status);
679 written = rc;
680 }
681 complete_all(&fw_buf->completion);
682 break;
683 }
684 /* fallthrough */
685 default:
686 dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
687 /* fallthrough */
688 case -1:
689 fw_load_abort(fw_priv);
690 break;
691 }
692 out:
693 mutex_unlock(&fw_lock);
694 return written;
695 }
696
697 static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
698
firmware_data_read(struct file * filp,struct kobject * kobj,struct bin_attribute * bin_attr,char * buffer,loff_t offset,size_t count)699 static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
700 struct bin_attribute *bin_attr,
701 char *buffer, loff_t offset, size_t count)
702 {
703 struct device *dev = kobj_to_dev(kobj);
704 struct firmware_priv *fw_priv = to_firmware_priv(dev);
705 struct firmware_buf *buf;
706 ssize_t ret_count;
707
708 mutex_lock(&fw_lock);
709 buf = fw_priv->buf;
710 if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
711 ret_count = -ENODEV;
712 goto out;
713 }
714 if (offset > buf->size) {
715 ret_count = 0;
716 goto out;
717 }
718 if (count > buf->size - offset)
719 count = buf->size - offset;
720
721 ret_count = count;
722
723 while (count) {
724 void *page_data;
725 int page_nr = offset >> PAGE_SHIFT;
726 int page_ofs = offset & (PAGE_SIZE-1);
727 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
728
729 page_data = kmap(buf->pages[page_nr]);
730
731 memcpy(buffer, page_data + page_ofs, page_cnt);
732
733 kunmap(buf->pages[page_nr]);
734 buffer += page_cnt;
735 offset += page_cnt;
736 count -= page_cnt;
737 }
738 out:
739 mutex_unlock(&fw_lock);
740 return ret_count;
741 }
742
fw_realloc_buffer(struct firmware_priv * fw_priv,int min_size)743 static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
744 {
745 struct firmware_buf *buf = fw_priv->buf;
746 int pages_needed = PAGE_ALIGN(min_size) >> PAGE_SHIFT;
747
748 /* If the array of pages is too small, grow it... */
749 if (buf->page_array_size < pages_needed) {
750 int new_array_size = max(pages_needed,
751 buf->page_array_size * 2);
752 struct page **new_pages;
753
754 new_pages = kmalloc(new_array_size * sizeof(void *),
755 GFP_KERNEL);
756 if (!new_pages) {
757 fw_load_abort(fw_priv);
758 return -ENOMEM;
759 }
760 memcpy(new_pages, buf->pages,
761 buf->page_array_size * sizeof(void *));
762 memset(&new_pages[buf->page_array_size], 0, sizeof(void *) *
763 (new_array_size - buf->page_array_size));
764 kfree(buf->pages);
765 buf->pages = new_pages;
766 buf->page_array_size = new_array_size;
767 }
768
769 while (buf->nr_pages < pages_needed) {
770 buf->pages[buf->nr_pages] =
771 alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
772
773 if (!buf->pages[buf->nr_pages]) {
774 fw_load_abort(fw_priv);
775 return -ENOMEM;
776 }
777 buf->nr_pages++;
778 }
779 return 0;
780 }
781
782 /**
783 * firmware_data_write - write method for firmware
784 * @filp: open sysfs file
785 * @kobj: kobject for the device
786 * @bin_attr: bin_attr structure
787 * @buffer: buffer being written
788 * @offset: buffer offset for write in total data store area
789 * @count: buffer size
790 *
791 * Data written to the 'data' attribute will be later handed to
792 * the driver as a firmware image.
793 **/
firmware_data_write(struct file * filp,struct kobject * kobj,struct bin_attribute * bin_attr,char * buffer,loff_t offset,size_t count)794 static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
795 struct bin_attribute *bin_attr,
796 char *buffer, loff_t offset, size_t count)
797 {
798 struct device *dev = kobj_to_dev(kobj);
799 struct firmware_priv *fw_priv = to_firmware_priv(dev);
800 struct firmware_buf *buf;
801 ssize_t retval;
802
803 if (!capable(CAP_SYS_RAWIO))
804 return -EPERM;
805
806 mutex_lock(&fw_lock);
807 buf = fw_priv->buf;
808 if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
809 retval = -ENODEV;
810 goto out;
811 }
812
813 retval = fw_realloc_buffer(fw_priv, offset + count);
814 if (retval)
815 goto out;
816
817 retval = count;
818
819 while (count) {
820 void *page_data;
821 int page_nr = offset >> PAGE_SHIFT;
822 int page_ofs = offset & (PAGE_SIZE - 1);
823 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
824
825 page_data = kmap(buf->pages[page_nr]);
826
827 memcpy(page_data + page_ofs, buffer, page_cnt);
828
829 kunmap(buf->pages[page_nr]);
830 buffer += page_cnt;
831 offset += page_cnt;
832 count -= page_cnt;
833 }
834
835 buf->size = max_t(size_t, offset, buf->size);
836 out:
837 mutex_unlock(&fw_lock);
838 return retval;
839 }
840
841 static struct bin_attribute firmware_attr_data = {
842 .attr = { .name = "data", .mode = 0644 },
843 .size = 0,
844 .read = firmware_data_read,
845 .write = firmware_data_write,
846 };
847
848 static struct attribute *fw_dev_attrs[] = {
849 &dev_attr_loading.attr,
850 NULL
851 };
852
853 static struct bin_attribute *fw_dev_bin_attrs[] = {
854 &firmware_attr_data,
855 NULL
856 };
857
858 static const struct attribute_group fw_dev_attr_group = {
859 .attrs = fw_dev_attrs,
860 .bin_attrs = fw_dev_bin_attrs,
861 };
862
863 static const struct attribute_group *fw_dev_attr_groups[] = {
864 &fw_dev_attr_group,
865 NULL
866 };
867
868 static struct firmware_priv *
fw_create_instance(struct firmware * firmware,const char * fw_name,struct device * device,unsigned int opt_flags)869 fw_create_instance(struct firmware *firmware, const char *fw_name,
870 struct device *device, unsigned int opt_flags)
871 {
872 struct firmware_priv *fw_priv;
873 struct device *f_dev;
874
875 fw_priv = kzalloc(sizeof(*fw_priv), GFP_KERNEL);
876 if (!fw_priv) {
877 fw_priv = ERR_PTR(-ENOMEM);
878 goto exit;
879 }
880
881 fw_priv->nowait = !!(opt_flags & FW_OPT_NOWAIT);
882 fw_priv->fw = firmware;
883 f_dev = &fw_priv->dev;
884
885 device_initialize(f_dev);
886 dev_set_name(f_dev, "%s", fw_name);
887 f_dev->parent = device;
888 f_dev->class = &firmware_class;
889 f_dev->groups = fw_dev_attr_groups;
890 exit:
891 return fw_priv;
892 }
893
894 /* load a firmware via user helper */
_request_firmware_load(struct firmware_priv * fw_priv,unsigned int opt_flags,long timeout)895 static int _request_firmware_load(struct firmware_priv *fw_priv,
896 unsigned int opt_flags, long timeout)
897 {
898 int retval = 0;
899 struct device *f_dev = &fw_priv->dev;
900 struct firmware_buf *buf = fw_priv->buf;
901
902 /* fall back on userspace loading */
903 buf->is_paged_buf = true;
904
905 dev_set_uevent_suppress(f_dev, true);
906
907 retval = device_add(f_dev);
908 if (retval) {
909 dev_err(f_dev, "%s: device_register failed\n", __func__);
910 goto err_put_dev;
911 }
912
913 mutex_lock(&fw_lock);
914 list_add(&buf->pending_list, &pending_fw_head);
915 mutex_unlock(&fw_lock);
916
917 if (opt_flags & FW_OPT_UEVENT) {
918 buf->need_uevent = true;
919 dev_set_uevent_suppress(f_dev, false);
920 dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id);
921 kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
922 } else {
923 timeout = MAX_JIFFY_OFFSET;
924 }
925
926 retval = wait_for_completion_interruptible_timeout(&buf->completion,
927 timeout);
928 if (retval == -ERESTARTSYS || !retval) {
929 mutex_lock(&fw_lock);
930 fw_load_abort(fw_priv);
931 mutex_unlock(&fw_lock);
932 } else if (retval > 0) {
933 retval = 0;
934 }
935
936 if (is_fw_load_aborted(buf))
937 retval = -EAGAIN;
938 else if (!buf->data)
939 retval = -ENOMEM;
940
941 device_del(f_dev);
942 err_put_dev:
943 put_device(f_dev);
944 return retval;
945 }
946
fw_load_from_user_helper(struct firmware * firmware,const char * name,struct device * device,unsigned int opt_flags,long timeout)947 static int fw_load_from_user_helper(struct firmware *firmware,
948 const char *name, struct device *device,
949 unsigned int opt_flags, long timeout)
950 {
951 struct firmware_priv *fw_priv;
952
953 fw_priv = fw_create_instance(firmware, name, device, opt_flags);
954 if (IS_ERR(fw_priv))
955 return PTR_ERR(fw_priv);
956
957 fw_priv->buf = firmware->priv;
958 return _request_firmware_load(fw_priv, opt_flags, timeout);
959 }
960
961 #ifdef CONFIG_PM_SLEEP
962 /* kill pending requests without uevent to avoid blocking suspend */
kill_requests_without_uevent(void)963 static void kill_requests_without_uevent(void)
964 {
965 struct firmware_buf *buf;
966 struct firmware_buf *next;
967
968 mutex_lock(&fw_lock);
969 list_for_each_entry_safe(buf, next, &pending_fw_head, pending_list) {
970 if (!buf->need_uevent)
971 __fw_load_abort(buf);
972 }
973 mutex_unlock(&fw_lock);
974 }
975 #endif
976
977 #else /* CONFIG_FW_LOADER_USER_HELPER */
978 static inline int
fw_load_from_user_helper(struct firmware * firmware,const char * name,struct device * device,unsigned int opt_flags,long timeout)979 fw_load_from_user_helper(struct firmware *firmware, const char *name,
980 struct device *device, unsigned int opt_flags,
981 long timeout)
982 {
983 return -ENOENT;
984 }
985
986 /* No abort during direct loading */
987 #define is_fw_load_aborted(buf) false
988
989 #ifdef CONFIG_PM_SLEEP
kill_requests_without_uevent(void)990 static inline void kill_requests_without_uevent(void) { }
991 #endif
992
993 #endif /* CONFIG_FW_LOADER_USER_HELPER */
994
995
996 /* wait until the shared firmware_buf becomes ready (or error) */
sync_cached_firmware_buf(struct firmware_buf * buf)997 static int sync_cached_firmware_buf(struct firmware_buf *buf)
998 {
999 int ret = 0;
1000
1001 mutex_lock(&fw_lock);
1002 while (!test_bit(FW_STATUS_DONE, &buf->status)) {
1003 if (is_fw_load_aborted(buf)) {
1004 ret = -ENOENT;
1005 break;
1006 }
1007 mutex_unlock(&fw_lock);
1008 ret = wait_for_completion_interruptible(&buf->completion);
1009 mutex_lock(&fw_lock);
1010 }
1011 mutex_unlock(&fw_lock);
1012 return ret;
1013 }
1014
1015 /* prepare firmware and firmware_buf structs;
1016 * return 0 if a firmware is already assigned, 1 if need to load one,
1017 * or a negative error code
1018 */
1019 static int
_request_firmware_prepare(struct firmware ** firmware_p,const char * name,struct device * device)1020 _request_firmware_prepare(struct firmware **firmware_p, const char *name,
1021 struct device *device)
1022 {
1023 struct firmware *firmware;
1024 struct firmware_buf *buf;
1025 int ret;
1026
1027 *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
1028 if (!firmware) {
1029 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
1030 __func__);
1031 return -ENOMEM;
1032 }
1033
1034 if (fw_get_builtin_firmware(firmware, name)) {
1035 dev_dbg(device, "firmware: using built-in firmware %s\n", name);
1036 return 0; /* assigned */
1037 }
1038
1039 ret = fw_lookup_and_allocate_buf(name, &fw_cache, &buf);
1040
1041 /*
1042 * bind with 'buf' now to avoid warning in failure path
1043 * of requesting firmware.
1044 */
1045 firmware->priv = buf;
1046
1047 if (ret > 0) {
1048 ret = sync_cached_firmware_buf(buf);
1049 if (!ret) {
1050 fw_set_page_data(buf, firmware);
1051 return 0; /* assigned */
1052 }
1053 }
1054
1055 if (ret < 0)
1056 return ret;
1057 return 1; /* need to load */
1058 }
1059
assign_firmware_buf(struct firmware * fw,struct device * device,unsigned int opt_flags)1060 static int assign_firmware_buf(struct firmware *fw, struct device *device,
1061 unsigned int opt_flags)
1062 {
1063 struct firmware_buf *buf = fw->priv;
1064
1065 mutex_lock(&fw_lock);
1066 if (!buf->size || is_fw_load_aborted(buf)) {
1067 mutex_unlock(&fw_lock);
1068 return -ENOENT;
1069 }
1070
1071 /*
1072 * add firmware name into devres list so that we can auto cache
1073 * and uncache firmware for device.
1074 *
1075 * device may has been deleted already, but the problem
1076 * should be fixed in devres or driver core.
1077 */
1078 /* don't cache firmware handled without uevent */
1079 if (device && (opt_flags & FW_OPT_UEVENT))
1080 fw_add_devm_name(device, buf->fw_id);
1081
1082 /*
1083 * After caching firmware image is started, let it piggyback
1084 * on request firmware.
1085 */
1086 if (buf->fwc->state == FW_LOADER_START_CACHE) {
1087 if (fw_cache_piggyback_on_request(buf->fw_id))
1088 kref_get(&buf->ref);
1089 }
1090
1091 /* pass the pages buffer to driver at the last minute */
1092 fw_set_page_data(buf, fw);
1093 mutex_unlock(&fw_lock);
1094 return 0;
1095 }
1096
1097 /* called from request_firmware() and request_firmware_work_func() */
1098 static int
_request_firmware(const struct firmware ** firmware_p,const char * name,struct device * device,unsigned int opt_flags)1099 _request_firmware(const struct firmware **firmware_p, const char *name,
1100 struct device *device, unsigned int opt_flags)
1101 {
1102 struct firmware *fw;
1103 long timeout;
1104 int ret;
1105
1106 if (!firmware_p)
1107 return -EINVAL;
1108
1109 if (!name || name[0] == '\0')
1110 return -EINVAL;
1111
1112 ret = _request_firmware_prepare(&fw, name, device);
1113 if (ret <= 0) /* error or already assigned */
1114 goto out;
1115
1116 ret = 0;
1117 timeout = firmware_loading_timeout();
1118 if (opt_flags & FW_OPT_NOWAIT) {
1119 timeout = usermodehelper_read_lock_wait(timeout);
1120 if (!timeout) {
1121 dev_dbg(device, "firmware: %s loading timed out\n",
1122 name);
1123 ret = -EBUSY;
1124 goto out;
1125 }
1126 } else {
1127 ret = usermodehelper_read_trylock();
1128 if (WARN_ON(ret)) {
1129 dev_err(device, "firmware: %s will not be loaded\n",
1130 name);
1131 goto out;
1132 }
1133 }
1134
1135 ret = fw_get_filesystem_firmware(device, fw->priv);
1136 if (ret) {
1137 if (!(opt_flags & FW_OPT_NO_WARN))
1138 dev_warn(device,
1139 "Direct firmware load for %s failed with error %d\n",
1140 name, ret);
1141 if (opt_flags & FW_OPT_USERHELPER) {
1142 dev_warn(device, "Falling back to user helper\n");
1143 ret = fw_load_from_user_helper(fw, name, device,
1144 opt_flags, timeout);
1145 }
1146 }
1147
1148 if (!ret)
1149 ret = assign_firmware_buf(fw, device, opt_flags);
1150
1151 usermodehelper_read_unlock();
1152
1153 out:
1154 if (ret < 0) {
1155 release_firmware(fw);
1156 fw = NULL;
1157 }
1158
1159 *firmware_p = fw;
1160 return ret;
1161 }
1162
1163 /**
1164 * request_firmware: - send firmware request and wait for it
1165 * @firmware_p: pointer to firmware image
1166 * @name: name of firmware file
1167 * @device: device for which firmware is being loaded
1168 *
1169 * @firmware_p will be used to return a firmware image by the name
1170 * of @name for device @device.
1171 *
1172 * Should be called from user context where sleeping is allowed.
1173 *
1174 * @name will be used as $FIRMWARE in the uevent environment and
1175 * should be distinctive enough not to be confused with any other
1176 * firmware image for this or any other device.
1177 *
1178 * Caller must hold the reference count of @device.
1179 *
1180 * The function can be called safely inside device's suspend and
1181 * resume callback.
1182 **/
1183 int
request_firmware(const struct firmware ** firmware_p,const char * name,struct device * device)1184 request_firmware(const struct firmware **firmware_p, const char *name,
1185 struct device *device)
1186 {
1187 int ret;
1188
1189 /* Need to pin this module until return */
1190 __module_get(THIS_MODULE);
1191 ret = _request_firmware(firmware_p, name, device,
1192 FW_OPT_UEVENT | FW_OPT_FALLBACK);
1193 module_put(THIS_MODULE);
1194 return ret;
1195 }
1196 EXPORT_SYMBOL(request_firmware);
1197
1198 /**
1199 * request_firmware_direct: - load firmware directly without usermode helper
1200 * @firmware_p: pointer to firmware image
1201 * @name: name of firmware file
1202 * @device: device for which firmware is being loaded
1203 *
1204 * This function works pretty much like request_firmware(), but this doesn't
1205 * fall back to usermode helper even if the firmware couldn't be loaded
1206 * directly from fs. Hence it's useful for loading optional firmwares, which
1207 * aren't always present, without extra long timeouts of udev.
1208 **/
request_firmware_direct(const struct firmware ** firmware_p,const char * name,struct device * device)1209 int request_firmware_direct(const struct firmware **firmware_p,
1210 const char *name, struct device *device)
1211 {
1212 int ret;
1213
1214 __module_get(THIS_MODULE);
1215 ret = _request_firmware(firmware_p, name, device,
1216 FW_OPT_UEVENT | FW_OPT_NO_WARN);
1217 module_put(THIS_MODULE);
1218 return ret;
1219 }
1220 EXPORT_SYMBOL_GPL(request_firmware_direct);
1221
1222 /**
1223 * release_firmware: - release the resource associated with a firmware image
1224 * @fw: firmware resource to release
1225 **/
release_firmware(const struct firmware * fw)1226 void release_firmware(const struct firmware *fw)
1227 {
1228 if (fw) {
1229 if (!fw_is_builtin_firmware(fw))
1230 firmware_free_data(fw);
1231 kfree(fw);
1232 }
1233 }
1234 EXPORT_SYMBOL(release_firmware);
1235
1236 /* Async support */
1237 struct firmware_work {
1238 struct work_struct work;
1239 struct module *module;
1240 const char *name;
1241 struct device *device;
1242 void *context;
1243 void (*cont)(const struct firmware *fw, void *context);
1244 unsigned int opt_flags;
1245 };
1246
request_firmware_work_func(struct work_struct * work)1247 static void request_firmware_work_func(struct work_struct *work)
1248 {
1249 struct firmware_work *fw_work;
1250 const struct firmware *fw;
1251
1252 fw_work = container_of(work, struct firmware_work, work);
1253
1254 _request_firmware(&fw, fw_work->name, fw_work->device,
1255 fw_work->opt_flags);
1256 fw_work->cont(fw, fw_work->context);
1257 put_device(fw_work->device); /* taken in request_firmware_nowait() */
1258
1259 module_put(fw_work->module);
1260 kfree(fw_work);
1261 }
1262
1263 /**
1264 * request_firmware_nowait - asynchronous version of request_firmware
1265 * @module: module requesting the firmware
1266 * @uevent: sends uevent to copy the firmware image if this flag
1267 * is non-zero else the firmware copy must be done manually.
1268 * @name: name of firmware file
1269 * @device: device for which firmware is being loaded
1270 * @gfp: allocation flags
1271 * @context: will be passed over to @cont, and
1272 * @fw may be %NULL if firmware request fails.
1273 * @cont: function will be called asynchronously when the firmware
1274 * request is over.
1275 *
1276 * Caller must hold the reference count of @device.
1277 *
1278 * Asynchronous variant of request_firmware() for user contexts:
1279 * - sleep for as small periods as possible since it may
1280 * increase kernel boot time of built-in device drivers
1281 * requesting firmware in their ->probe() methods, if
1282 * @gfp is GFP_KERNEL.
1283 *
1284 * - can't sleep at all if @gfp is GFP_ATOMIC.
1285 **/
1286 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))1287 request_firmware_nowait(
1288 struct module *module, bool uevent,
1289 const char *name, struct device *device, gfp_t gfp, void *context,
1290 void (*cont)(const struct firmware *fw, void *context))
1291 {
1292 struct firmware_work *fw_work;
1293
1294 fw_work = kzalloc(sizeof(struct firmware_work), gfp);
1295 if (!fw_work)
1296 return -ENOMEM;
1297
1298 fw_work->module = module;
1299 fw_work->name = name;
1300 fw_work->device = device;
1301 fw_work->context = context;
1302 fw_work->cont = cont;
1303 fw_work->opt_flags = FW_OPT_NOWAIT | FW_OPT_FALLBACK |
1304 (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
1305
1306 if (!try_module_get(module)) {
1307 kfree(fw_work);
1308 return -EFAULT;
1309 }
1310
1311 get_device(fw_work->device);
1312 INIT_WORK(&fw_work->work, request_firmware_work_func);
1313 schedule_work(&fw_work->work);
1314 return 0;
1315 }
1316 EXPORT_SYMBOL(request_firmware_nowait);
1317
1318 #ifdef CONFIG_PM_SLEEP
1319 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1320
1321 /**
1322 * cache_firmware - cache one firmware image in kernel memory space
1323 * @fw_name: the firmware image name
1324 *
1325 * Cache firmware in kernel memory so that drivers can use it when
1326 * system isn't ready for them to request firmware image from userspace.
1327 * Once it returns successfully, driver can use request_firmware or its
1328 * nowait version to get the cached firmware without any interacting
1329 * with userspace
1330 *
1331 * Return 0 if the firmware image has been cached successfully
1332 * Return !0 otherwise
1333 *
1334 */
cache_firmware(const char * fw_name)1335 static int cache_firmware(const char *fw_name)
1336 {
1337 int ret;
1338 const struct firmware *fw;
1339
1340 pr_debug("%s: %s\n", __func__, fw_name);
1341
1342 ret = request_firmware(&fw, fw_name, NULL);
1343 if (!ret)
1344 kfree(fw);
1345
1346 pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1347
1348 return ret;
1349 }
1350
fw_lookup_buf(const char * fw_name)1351 static struct firmware_buf *fw_lookup_buf(const char *fw_name)
1352 {
1353 struct firmware_buf *tmp;
1354 struct firmware_cache *fwc = &fw_cache;
1355
1356 spin_lock(&fwc->lock);
1357 tmp = __fw_lookup_buf(fw_name);
1358 spin_unlock(&fwc->lock);
1359
1360 return tmp;
1361 }
1362
1363 /**
1364 * uncache_firmware - remove one cached firmware image
1365 * @fw_name: the firmware image name
1366 *
1367 * Uncache one firmware image which has been cached successfully
1368 * before.
1369 *
1370 * Return 0 if the firmware cache has been removed successfully
1371 * Return !0 otherwise
1372 *
1373 */
uncache_firmware(const char * fw_name)1374 static int uncache_firmware(const char *fw_name)
1375 {
1376 struct firmware_buf *buf;
1377 struct firmware fw;
1378
1379 pr_debug("%s: %s\n", __func__, fw_name);
1380
1381 if (fw_get_builtin_firmware(&fw, fw_name))
1382 return 0;
1383
1384 buf = fw_lookup_buf(fw_name);
1385 if (buf) {
1386 fw_free_buf(buf);
1387 return 0;
1388 }
1389
1390 return -EINVAL;
1391 }
1392
alloc_fw_cache_entry(const char * name)1393 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1394 {
1395 struct fw_cache_entry *fce;
1396
1397 fce = kzalloc(sizeof(*fce) + strlen(name) + 1, GFP_ATOMIC);
1398 if (!fce)
1399 goto exit;
1400
1401 strcpy(fce->name, name);
1402 exit:
1403 return fce;
1404 }
1405
__fw_entry_found(const char * name)1406 static int __fw_entry_found(const char *name)
1407 {
1408 struct firmware_cache *fwc = &fw_cache;
1409 struct fw_cache_entry *fce;
1410
1411 list_for_each_entry(fce, &fwc->fw_names, list) {
1412 if (!strcmp(fce->name, name))
1413 return 1;
1414 }
1415 return 0;
1416 }
1417
fw_cache_piggyback_on_request(const char * name)1418 static int fw_cache_piggyback_on_request(const char *name)
1419 {
1420 struct firmware_cache *fwc = &fw_cache;
1421 struct fw_cache_entry *fce;
1422 int ret = 0;
1423
1424 spin_lock(&fwc->name_lock);
1425 if (__fw_entry_found(name))
1426 goto found;
1427
1428 fce = alloc_fw_cache_entry(name);
1429 if (fce) {
1430 ret = 1;
1431 list_add(&fce->list, &fwc->fw_names);
1432 pr_debug("%s: fw: %s\n", __func__, name);
1433 }
1434 found:
1435 spin_unlock(&fwc->name_lock);
1436 return ret;
1437 }
1438
free_fw_cache_entry(struct fw_cache_entry * fce)1439 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1440 {
1441 kfree(fce);
1442 }
1443
__async_dev_cache_fw_image(void * fw_entry,async_cookie_t cookie)1444 static void __async_dev_cache_fw_image(void *fw_entry,
1445 async_cookie_t cookie)
1446 {
1447 struct fw_cache_entry *fce = fw_entry;
1448 struct firmware_cache *fwc = &fw_cache;
1449 int ret;
1450
1451 ret = cache_firmware(fce->name);
1452 if (ret) {
1453 spin_lock(&fwc->name_lock);
1454 list_del(&fce->list);
1455 spin_unlock(&fwc->name_lock);
1456
1457 free_fw_cache_entry(fce);
1458 }
1459 }
1460
1461 /* called with dev->devres_lock held */
dev_create_fw_entry(struct device * dev,void * res,void * data)1462 static void dev_create_fw_entry(struct device *dev, void *res,
1463 void *data)
1464 {
1465 struct fw_name_devm *fwn = res;
1466 const char *fw_name = fwn->name;
1467 struct list_head *head = data;
1468 struct fw_cache_entry *fce;
1469
1470 fce = alloc_fw_cache_entry(fw_name);
1471 if (fce)
1472 list_add(&fce->list, head);
1473 }
1474
devm_name_match(struct device * dev,void * res,void * match_data)1475 static int devm_name_match(struct device *dev, void *res,
1476 void *match_data)
1477 {
1478 struct fw_name_devm *fwn = res;
1479 return (fwn->magic == (unsigned long)match_data);
1480 }
1481
dev_cache_fw_image(struct device * dev,void * data)1482 static void dev_cache_fw_image(struct device *dev, void *data)
1483 {
1484 LIST_HEAD(todo);
1485 struct fw_cache_entry *fce;
1486 struct fw_cache_entry *fce_next;
1487 struct firmware_cache *fwc = &fw_cache;
1488
1489 devres_for_each_res(dev, fw_name_devm_release,
1490 devm_name_match, &fw_cache,
1491 dev_create_fw_entry, &todo);
1492
1493 list_for_each_entry_safe(fce, fce_next, &todo, list) {
1494 list_del(&fce->list);
1495
1496 spin_lock(&fwc->name_lock);
1497 /* only one cache entry for one firmware */
1498 if (!__fw_entry_found(fce->name)) {
1499 list_add(&fce->list, &fwc->fw_names);
1500 } else {
1501 free_fw_cache_entry(fce);
1502 fce = NULL;
1503 }
1504 spin_unlock(&fwc->name_lock);
1505
1506 if (fce)
1507 async_schedule_domain(__async_dev_cache_fw_image,
1508 (void *)fce,
1509 &fw_cache_domain);
1510 }
1511 }
1512
__device_uncache_fw_images(void)1513 static void __device_uncache_fw_images(void)
1514 {
1515 struct firmware_cache *fwc = &fw_cache;
1516 struct fw_cache_entry *fce;
1517
1518 spin_lock(&fwc->name_lock);
1519 while (!list_empty(&fwc->fw_names)) {
1520 fce = list_entry(fwc->fw_names.next,
1521 struct fw_cache_entry, list);
1522 list_del(&fce->list);
1523 spin_unlock(&fwc->name_lock);
1524
1525 uncache_firmware(fce->name);
1526 free_fw_cache_entry(fce);
1527
1528 spin_lock(&fwc->name_lock);
1529 }
1530 spin_unlock(&fwc->name_lock);
1531 }
1532
1533 /**
1534 * device_cache_fw_images - cache devices' firmware
1535 *
1536 * If one device called request_firmware or its nowait version
1537 * successfully before, the firmware names are recored into the
1538 * device's devres link list, so device_cache_fw_images can call
1539 * cache_firmware() to cache these firmwares for the device,
1540 * then the device driver can load its firmwares easily at
1541 * time when system is not ready to complete loading firmware.
1542 */
device_cache_fw_images(void)1543 static void device_cache_fw_images(void)
1544 {
1545 struct firmware_cache *fwc = &fw_cache;
1546 int old_timeout;
1547 DEFINE_WAIT(wait);
1548
1549 pr_debug("%s\n", __func__);
1550
1551 /* cancel uncache work */
1552 cancel_delayed_work_sync(&fwc->work);
1553
1554 /*
1555 * use small loading timeout for caching devices' firmware
1556 * because all these firmware images have been loaded
1557 * successfully at lease once, also system is ready for
1558 * completing firmware loading now. The maximum size of
1559 * firmware in current distributions is about 2M bytes,
1560 * so 10 secs should be enough.
1561 */
1562 old_timeout = loading_timeout;
1563 loading_timeout = 10;
1564
1565 mutex_lock(&fw_lock);
1566 fwc->state = FW_LOADER_START_CACHE;
1567 dpm_for_each_dev(NULL, dev_cache_fw_image);
1568 mutex_unlock(&fw_lock);
1569
1570 /* wait for completion of caching firmware for all devices */
1571 async_synchronize_full_domain(&fw_cache_domain);
1572
1573 loading_timeout = old_timeout;
1574 }
1575
1576 /**
1577 * device_uncache_fw_images - uncache devices' firmware
1578 *
1579 * uncache all firmwares which have been cached successfully
1580 * by device_uncache_fw_images earlier
1581 */
device_uncache_fw_images(void)1582 static void device_uncache_fw_images(void)
1583 {
1584 pr_debug("%s\n", __func__);
1585 __device_uncache_fw_images();
1586 }
1587
device_uncache_fw_images_work(struct work_struct * work)1588 static void device_uncache_fw_images_work(struct work_struct *work)
1589 {
1590 device_uncache_fw_images();
1591 }
1592
1593 /**
1594 * device_uncache_fw_images_delay - uncache devices firmwares
1595 * @delay: number of milliseconds to delay uncache device firmwares
1596 *
1597 * uncache all devices's firmwares which has been cached successfully
1598 * by device_cache_fw_images after @delay milliseconds.
1599 */
device_uncache_fw_images_delay(unsigned long delay)1600 static void device_uncache_fw_images_delay(unsigned long delay)
1601 {
1602 queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1603 msecs_to_jiffies(delay));
1604 }
1605
fw_pm_notify(struct notifier_block * notify_block,unsigned long mode,void * unused)1606 static int fw_pm_notify(struct notifier_block *notify_block,
1607 unsigned long mode, void *unused)
1608 {
1609 switch (mode) {
1610 case PM_HIBERNATION_PREPARE:
1611 case PM_SUSPEND_PREPARE:
1612 case PM_RESTORE_PREPARE:
1613 kill_requests_without_uevent();
1614 device_cache_fw_images();
1615 break;
1616
1617 case PM_POST_SUSPEND:
1618 case PM_POST_HIBERNATION:
1619 case PM_POST_RESTORE:
1620 /*
1621 * In case that system sleep failed and syscore_suspend is
1622 * not called.
1623 */
1624 mutex_lock(&fw_lock);
1625 fw_cache.state = FW_LOADER_NO_CACHE;
1626 mutex_unlock(&fw_lock);
1627
1628 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1629 break;
1630 }
1631
1632 return 0;
1633 }
1634
1635 /* stop caching firmware once syscore_suspend is reached */
fw_suspend(void)1636 static int fw_suspend(void)
1637 {
1638 fw_cache.state = FW_LOADER_NO_CACHE;
1639 return 0;
1640 }
1641
1642 static struct syscore_ops fw_syscore_ops = {
1643 .suspend = fw_suspend,
1644 };
1645 #else
fw_cache_piggyback_on_request(const char * name)1646 static int fw_cache_piggyback_on_request(const char *name)
1647 {
1648 return 0;
1649 }
1650 #endif
1651
fw_cache_init(void)1652 static void __init fw_cache_init(void)
1653 {
1654 spin_lock_init(&fw_cache.lock);
1655 INIT_LIST_HEAD(&fw_cache.head);
1656 fw_cache.state = FW_LOADER_NO_CACHE;
1657
1658 #ifdef CONFIG_PM_SLEEP
1659 spin_lock_init(&fw_cache.name_lock);
1660 INIT_LIST_HEAD(&fw_cache.fw_names);
1661
1662 INIT_DELAYED_WORK(&fw_cache.work,
1663 device_uncache_fw_images_work);
1664
1665 fw_cache.pm_notify.notifier_call = fw_pm_notify;
1666 register_pm_notifier(&fw_cache.pm_notify);
1667
1668 register_syscore_ops(&fw_syscore_ops);
1669 #endif
1670 }
1671
firmware_class_init(void)1672 static int __init firmware_class_init(void)
1673 {
1674 fw_cache_init();
1675 #ifdef CONFIG_FW_LOADER_USER_HELPER
1676 register_reboot_notifier(&fw_shutdown_nb);
1677 return class_register(&firmware_class);
1678 #else
1679 return 0;
1680 #endif
1681 }
1682
firmware_class_exit(void)1683 static void __exit firmware_class_exit(void)
1684 {
1685 #ifdef CONFIG_PM_SLEEP
1686 unregister_syscore_ops(&fw_syscore_ops);
1687 unregister_pm_notifier(&fw_cache.pm_notify);
1688 #endif
1689 #ifdef CONFIG_FW_LOADER_USER_HELPER
1690 unregister_reboot_notifier(&fw_shutdown_nb);
1691 class_unregister(&firmware_class);
1692 #endif
1693 }
1694
1695 fs_initcall(firmware_class_init);
1696 module_exit(firmware_class_exit);
1697