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v3.1
  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/kthread.h>
 20#include <linux/highmem.h>
 21#include <linux/firmware.h>
 22#include <linux/slab.h>
 
 
 
 
 
 
 
 
 
 
 
 23
 24#define to_dev(obj) container_of(obj, struct device, kobj)
 
 
 25
 26MODULE_AUTHOR("Manuel Estrada Sainz");
 27MODULE_DESCRIPTION("Multi purpose firmware loading support");
 28MODULE_LICENSE("GPL");
 29
 30/* Builtin firmware support */
 31
 32#ifdef CONFIG_FW_LOADER
 33
 34extern struct builtin_fw __start_builtin_fw[];
 35extern struct builtin_fw __end_builtin_fw[];
 36
 37static bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
 
 38{
 39	struct builtin_fw *b_fw;
 40
 41	for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
 42		if (strcmp(name, b_fw->name) == 0) {
 43			fw->size = b_fw->size;
 44			fw->data = b_fw->data;
 
 
 
 45			return true;
 46		}
 47	}
 48
 49	return false;
 50}
 51
 52static bool fw_is_builtin_firmware(const struct firmware *fw)
 53{
 54	struct builtin_fw *b_fw;
 55
 56	for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
 57		if (fw->data == b_fw->data)
 58			return true;
 59
 60	return false;
 61}
 62
 63#else /* Module case - no builtin firmware support */
 64
 65static inline bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
 
 
 66{
 67	return false;
 68}
 69
 70static inline bool fw_is_builtin_firmware(const struct firmware *fw)
 71{
 72	return false;
 73}
 74#endif
 75
 76enum {
 
 77	FW_STATUS_LOADING,
 78	FW_STATUS_DONE,
 79	FW_STATUS_ABORT,
 80};
 81
 82static int loading_timeout = 60;	/* In seconds */
 83
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 84/* fw_lock could be moved to 'struct firmware_priv' but since it is just
 85 * guarding for corner cases a global lock should be OK */
 86static DEFINE_MUTEX(fw_lock);
 87
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 88struct firmware_priv {
 89	struct completion completion;
 90	struct firmware *fw;
 91	unsigned long status;
 92	struct page **pages;
 93	int nr_pages;
 94	int page_array_size;
 95	struct timer_list timeout;
 96	struct device dev;
 97	bool nowait;
 98	char fw_id[];
 
 
 99};
100
101static struct firmware_priv *to_firmware_priv(struct device *dev)
102{
103	return container_of(dev, struct firmware_priv, dev);
104}
105
 
 
 
 
 
 
 
 
 
 
 
 
 
106static void fw_load_abort(struct firmware_priv *fw_priv)
107{
108	set_bit(FW_STATUS_ABORT, &fw_priv->status);
109	wmb();
110	complete(&fw_priv->completion);
111}
112
113static ssize_t firmware_timeout_show(struct class *class,
114				     struct class_attribute *attr,
115				     char *buf)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
116{
117	return sprintf(buf, "%d\n", loading_timeout);
118}
119
120/**
121 * firmware_timeout_store - set number of seconds to wait for firmware
122 * @class: device class pointer
123 * @attr: device attribute pointer
124 * @buf: buffer to scan for timeout value
125 * @count: number of bytes in @buf
126 *
127 *	Sets the number of seconds to wait for the firmware.  Once
128 *	this expires an error will be returned to the driver and no
129 *	firmware will be provided.
130 *
131 *	Note: zero means 'wait forever'.
132 **/
133static ssize_t firmware_timeout_store(struct class *class,
134				      struct class_attribute *attr,
135				      const char *buf, size_t count)
136{
137	loading_timeout = simple_strtol(buf, NULL, 10);
138	if (loading_timeout < 0)
139		loading_timeout = 0;
140
141	return count;
142}
 
143
144static struct class_attribute firmware_class_attrs[] = {
145	__ATTR(timeout, S_IWUSR | S_IRUGO,
146		firmware_timeout_show, firmware_timeout_store),
147	__ATTR_NULL
148};
 
149
150static void fw_dev_release(struct device *dev)
151{
152	struct firmware_priv *fw_priv = to_firmware_priv(dev);
153	int i;
154
155	for (i = 0; i < fw_priv->nr_pages; i++)
156		__free_page(fw_priv->pages[i]);
157	kfree(fw_priv->pages);
158	kfree(fw_priv);
159
160	module_put(THIS_MODULE);
161}
162
163static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
164{
165	struct firmware_priv *fw_priv = to_firmware_priv(dev);
166
167	if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->fw_id))
168		return -ENOMEM;
169	if (add_uevent_var(env, "TIMEOUT=%i", loading_timeout))
170		return -ENOMEM;
171	if (add_uevent_var(env, "ASYNC=%d", fw_priv->nowait))
172		return -ENOMEM;
173
174	return 0;
175}
176
 
 
 
 
 
 
 
 
 
 
 
 
177static struct class firmware_class = {
178	.name		= "firmware",
179	.class_attrs	= firmware_class_attrs,
180	.dev_uevent	= firmware_uevent,
181	.dev_release	= fw_dev_release,
182};
183
184static ssize_t firmware_loading_show(struct device *dev,
185				     struct device_attribute *attr, char *buf)
186{
187	struct firmware_priv *fw_priv = to_firmware_priv(dev);
188	int loading = test_bit(FW_STATUS_LOADING, &fw_priv->status);
189
190	return sprintf(buf, "%d\n", loading);
191}
 
 
192
193static void firmware_free_data(const struct firmware *fw)
194{
195	int i;
196	vunmap(fw->data);
197	if (fw->pages) {
198		for (i = 0; i < PFN_UP(fw->size); i++)
199			__free_page(fw->pages[i]);
200		kfree(fw->pages);
201	}
202}
203
204/* Some architectures don't have PAGE_KERNEL_RO */
205#ifndef PAGE_KERNEL_RO
206#define PAGE_KERNEL_RO PAGE_KERNEL
207#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
208/**
209 * firmware_loading_store - set value in the 'loading' control file
210 * @dev: device pointer
211 * @attr: device attribute pointer
212 * @buf: buffer to scan for loading control value
213 * @count: number of bytes in @buf
214 *
215 *	The relevant values are:
216 *
217 *	 1: Start a load, discarding any previous partial load.
218 *	 0: Conclude the load and hand the data to the driver code.
219 *	-1: Conclude the load with an error and discard any written data.
220 **/
221static ssize_t firmware_loading_store(struct device *dev,
222				      struct device_attribute *attr,
223				      const char *buf, size_t count)
224{
225	struct firmware_priv *fw_priv = to_firmware_priv(dev);
 
 
226	int loading = simple_strtol(buf, NULL, 10);
227	int i;
228
 
 
 
 
 
229	switch (loading) {
230	case 1:
231		mutex_lock(&fw_lock);
232		if (!fw_priv->fw) {
233			mutex_unlock(&fw_lock);
234			break;
 
 
 
 
 
235		}
236		firmware_free_data(fw_priv->fw);
237		memset(fw_priv->fw, 0, sizeof(struct firmware));
238		/* If the pages are not owned by 'struct firmware' */
239		for (i = 0; i < fw_priv->nr_pages; i++)
240			__free_page(fw_priv->pages[i]);
241		kfree(fw_priv->pages);
242		fw_priv->pages = NULL;
243		fw_priv->page_array_size = 0;
244		fw_priv->nr_pages = 0;
245		set_bit(FW_STATUS_LOADING, &fw_priv->status);
246		mutex_unlock(&fw_lock);
247		break;
248	case 0:
249		if (test_bit(FW_STATUS_LOADING, &fw_priv->status)) {
250			vunmap(fw_priv->fw->data);
251			fw_priv->fw->data = vmap(fw_priv->pages,
252						 fw_priv->nr_pages,
253						 0, PAGE_KERNEL_RO);
254			if (!fw_priv->fw->data) {
255				dev_err(dev, "%s: vmap() failed\n", __func__);
256				goto err;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
257			}
258			/* Pages are now owned by 'struct firmware' */
259			fw_priv->fw->pages = fw_priv->pages;
260			fw_priv->pages = NULL;
261
262			fw_priv->page_array_size = 0;
263			fw_priv->nr_pages = 0;
264			complete(&fw_priv->completion);
265			clear_bit(FW_STATUS_LOADING, &fw_priv->status);
266			break;
267		}
268		/* fallthrough */
269	default:
270		dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
271		/* fallthrough */
272	case -1:
273	err:
274		fw_load_abort(fw_priv);
275		break;
276	}
277
278	return count;
 
279}
280
281static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
282
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
283static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
284				  struct bin_attribute *bin_attr,
285				  char *buffer, loff_t offset, size_t count)
286{
287	struct device *dev = to_dev(kobj);
288	struct firmware_priv *fw_priv = to_firmware_priv(dev);
289	struct firmware *fw;
290	ssize_t ret_count;
291
292	mutex_lock(&fw_lock);
293	fw = fw_priv->fw;
294	if (!fw || test_bit(FW_STATUS_DONE, &fw_priv->status)) {
295		ret_count = -ENODEV;
296		goto out;
297	}
298	if (offset > fw->size) {
299		ret_count = 0;
300		goto out;
301	}
302	if (count > fw->size - offset)
303		count = fw->size - offset;
304
305	ret_count = count;
306
307	while (count) {
308		void *page_data;
309		int page_nr = offset >> PAGE_SHIFT;
310		int page_ofs = offset & (PAGE_SIZE-1);
311		int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
312
313		page_data = kmap(fw_priv->pages[page_nr]);
314
315		memcpy(buffer, page_data + page_ofs, page_cnt);
316
317		kunmap(fw_priv->pages[page_nr]);
318		buffer += page_cnt;
319		offset += page_cnt;
320		count -= page_cnt;
321	}
322out:
323	mutex_unlock(&fw_lock);
324	return ret_count;
325}
326
327static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
328{
329	int pages_needed = ALIGN(min_size, PAGE_SIZE) >> PAGE_SHIFT;
 
330
331	/* If the array of pages is too small, grow it... */
332	if (fw_priv->page_array_size < pages_needed) {
333		int new_array_size = max(pages_needed,
334					 fw_priv->page_array_size * 2);
335		struct page **new_pages;
336
337		new_pages = kmalloc(new_array_size * sizeof(void *),
338				    GFP_KERNEL);
339		if (!new_pages) {
340			fw_load_abort(fw_priv);
341			return -ENOMEM;
342		}
343		memcpy(new_pages, fw_priv->pages,
344		       fw_priv->page_array_size * sizeof(void *));
345		memset(&new_pages[fw_priv->page_array_size], 0, sizeof(void *) *
346		       (new_array_size - fw_priv->page_array_size));
347		kfree(fw_priv->pages);
348		fw_priv->pages = new_pages;
349		fw_priv->page_array_size = new_array_size;
350	}
351
352	while (fw_priv->nr_pages < pages_needed) {
353		fw_priv->pages[fw_priv->nr_pages] =
354			alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
355
356		if (!fw_priv->pages[fw_priv->nr_pages]) {
357			fw_load_abort(fw_priv);
358			return -ENOMEM;
359		}
360		fw_priv->nr_pages++;
361	}
362	return 0;
363}
364
365/**
366 * firmware_data_write - write method for firmware
367 * @filp: open sysfs file
368 * @kobj: kobject for the device
369 * @bin_attr: bin_attr structure
370 * @buffer: buffer being written
371 * @offset: buffer offset for write in total data store area
372 * @count: buffer size
373 *
374 *	Data written to the 'data' attribute will be later handed to
375 *	the driver as a firmware image.
376 **/
377static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
378				   struct bin_attribute *bin_attr,
379				   char *buffer, loff_t offset, size_t count)
380{
381	struct device *dev = to_dev(kobj);
382	struct firmware_priv *fw_priv = to_firmware_priv(dev);
383	struct firmware *fw;
384	ssize_t retval;
385
386	if (!capable(CAP_SYS_RAWIO))
387		return -EPERM;
388
389	mutex_lock(&fw_lock);
390	fw = fw_priv->fw;
391	if (!fw || test_bit(FW_STATUS_DONE, &fw_priv->status)) {
392		retval = -ENODEV;
393		goto out;
394	}
395	retval = fw_realloc_buffer(fw_priv, offset + count);
396	if (retval)
397		goto out;
398
399	retval = count;
400
401	while (count) {
402		void *page_data;
403		int page_nr = offset >> PAGE_SHIFT;
404		int page_ofs = offset & (PAGE_SIZE - 1);
405		int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
406
407		page_data = kmap(fw_priv->pages[page_nr]);
408
409		memcpy(page_data + page_ofs, buffer, page_cnt);
 
 
 
 
 
 
 
 
410
411		kunmap(fw_priv->pages[page_nr]);
412		buffer += page_cnt;
413		offset += page_cnt;
414		count -= page_cnt;
415	}
416
417	fw->size = max_t(size_t, offset, fw->size);
418out:
419	mutex_unlock(&fw_lock);
420	return retval;
421}
422
423static struct bin_attribute firmware_attr_data = {
424	.attr = { .name = "data", .mode = 0644 },
425	.size = 0,
426	.read = firmware_data_read,
427	.write = firmware_data_write,
428};
429
430static void firmware_class_timeout(u_long data)
431{
432	struct firmware_priv *fw_priv = (struct firmware_priv *) data;
 
433
434	fw_load_abort(fw_priv);
435}
 
 
 
 
 
 
 
 
 
 
 
 
436
437static struct firmware_priv *
438fw_create_instance(struct firmware *firmware, const char *fw_name,
439		   struct device *device, bool uevent, bool nowait)
440{
441	struct firmware_priv *fw_priv;
442	struct device *f_dev;
443	int error;
444
445	fw_priv = kzalloc(sizeof(*fw_priv) + strlen(fw_name) + 1 , GFP_KERNEL);
446	if (!fw_priv) {
447		dev_err(device, "%s: kmalloc failed\n", __func__);
448		error = -ENOMEM;
449		goto err_out;
450	}
451
 
452	fw_priv->fw = firmware;
453	fw_priv->nowait = nowait;
454	strcpy(fw_priv->fw_id, fw_name);
455	init_completion(&fw_priv->completion);
456	setup_timer(&fw_priv->timeout,
457		    firmware_class_timeout, (u_long) fw_priv);
458
459	f_dev = &fw_priv->dev;
460
461	device_initialize(f_dev);
462	dev_set_name(f_dev, "%s", dev_name(device));
463	f_dev->parent = device;
464	f_dev->class = &firmware_class;
 
 
 
 
465
466	dev_set_uevent_suppress(f_dev, true);
 
 
 
 
 
 
467
468	/* Need to pin this module until class device is destroyed */
469	__module_get(THIS_MODULE);
 
 
 
470
471	error = device_add(f_dev);
472	if (error) {
473		dev_err(device, "%s: device_register failed\n", __func__);
474		goto err_put_dev;
475	}
476
477	error = device_create_bin_file(f_dev, &firmware_attr_data);
478	if (error) {
479		dev_err(device, "%s: sysfs_create_bin_file failed\n", __func__);
480		goto err_del_dev;
481	}
482
483	error = device_create_file(f_dev, &dev_attr_loading);
484	if (error) {
485		dev_err(device, "%s: device_create_file failed\n", __func__);
486		goto err_del_bin_attr;
 
 
 
487	}
488
489	if (uevent)
490		dev_set_uevent_suppress(f_dev, false);
 
 
 
 
491
492	return fw_priv;
 
 
 
493
494err_del_bin_attr:
495	device_remove_bin_file(f_dev, &firmware_attr_data);
496err_del_dev:
497	device_del(f_dev);
498err_put_dev:
499	put_device(f_dev);
500err_out:
501	return ERR_PTR(error);
502}
503
504static void fw_destroy_instance(struct firmware_priv *fw_priv)
 
 
505{
506	struct device *f_dev = &fw_priv->dev;
507
508	device_remove_file(f_dev, &dev_attr_loading);
509	device_remove_bin_file(f_dev, &firmware_attr_data);
510	device_unregister(f_dev);
 
 
 
511}
512
513static int _request_firmware(const struct firmware **firmware_p,
514			     const char *name, struct device *device,
515			     bool uevent, bool nowait)
516{
517	struct firmware_priv *fw_priv;
518	struct firmware *firmware;
519	int retval = 0;
520
521	if (!firmware_p)
522		return -EINVAL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
523
524	*firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
525	if (!firmware) {
526		dev_err(device, "%s: kmalloc(struct firmware) failed\n",
527			__func__);
528		retval = -ENOMEM;
529		goto out;
530	}
531
532	if (fw_get_builtin_firmware(firmware, name)) {
533		dev_dbg(device, "firmware: using built-in firmware %s\n", name);
534		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
535	}
536
537	if (WARN_ON(usermodehelper_is_disabled())) {
538		dev_err(device, "firmware: %s will not be loaded\n", name);
539		retval = -EBUSY;
540		goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
541	}
542
543	if (uevent)
544		dev_dbg(device, "firmware: requesting %s\n", name);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
545
546	fw_priv = fw_create_instance(firmware, name, device, uevent, nowait);
547	if (IS_ERR(fw_priv)) {
548		retval = PTR_ERR(fw_priv);
549		goto out;
550	}
551
552	if (uevent) {
553		if (loading_timeout > 0)
554			mod_timer(&fw_priv->timeout,
555				  round_jiffies_up(jiffies +
556						   loading_timeout * HZ));
557
558		kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
559	}
560
561	wait_for_completion(&fw_priv->completion);
562
563	set_bit(FW_STATUS_DONE, &fw_priv->status);
564	del_timer_sync(&fw_priv->timeout);
 
 
 
 
 
 
 
 
565
566	mutex_lock(&fw_lock);
567	if (!fw_priv->fw->size || test_bit(FW_STATUS_ABORT, &fw_priv->status))
568		retval = -ENOENT;
569	fw_priv->fw = NULL;
570	mutex_unlock(&fw_lock);
571
572	fw_destroy_instance(fw_priv);
573
574out:
575	if (retval) {
576		release_firmware(firmware);
577		*firmware_p = NULL;
578	}
579
580	return retval;
 
581}
582
583/**
584 * request_firmware: - send firmware request and wait for it
585 * @firmware_p: pointer to firmware image
586 * @name: name of firmware file
587 * @device: device for which firmware is being loaded
588 *
589 *      @firmware_p will be used to return a firmware image by the name
590 *      of @name for device @device.
591 *
592 *      Should be called from user context where sleeping is allowed.
593 *
594 *      @name will be used as $FIRMWARE in the uevent environment and
595 *      should be distinctive enough not to be confused with any other
596 *      firmware image for this or any other device.
 
 
 
 
 
597 **/
598int
599request_firmware(const struct firmware **firmware_p, const char *name,
600                 struct device *device)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
601{
602        return _request_firmware(firmware_p, name, device, true, false);
 
 
 
 
 
 
 
603}
 
604
605/**
606 * release_firmware: - release the resource associated with a firmware image
607 * @fw: firmware resource to release
608 **/
609void release_firmware(const struct firmware *fw)
610{
611	if (fw) {
612		if (!fw_is_builtin_firmware(fw))
613			firmware_free_data(fw);
614		kfree(fw);
615	}
616}
 
617
618/* Async support */
619struct firmware_work {
620	struct work_struct work;
621	struct module *module;
622	const char *name;
623	struct device *device;
624	void *context;
625	void (*cont)(const struct firmware *fw, void *context);
626	bool uevent;
627};
628
629static int request_firmware_work_func(void *arg)
630{
631	struct firmware_work *fw_work = arg;
632	const struct firmware *fw;
633	int ret;
634
635	if (!arg) {
636		WARN_ON(1);
637		return 0;
638	}
639
640	ret = _request_firmware(&fw, fw_work->name, fw_work->device,
641				fw_work->uevent, true);
642	fw_work->cont(fw, fw_work->context);
 
643
644	module_put(fw_work->module);
 
645	kfree(fw_work);
646
647	return ret;
648}
649
650/**
651 * request_firmware_nowait - asynchronous version of request_firmware
652 * @module: module requesting the firmware
653 * @uevent: sends uevent to copy the firmware image if this flag
654 *	is non-zero else the firmware copy must be done manually.
655 * @name: name of firmware file
656 * @device: device for which firmware is being loaded
657 * @gfp: allocation flags
658 * @context: will be passed over to @cont, and
659 *	@fw may be %NULL if firmware request fails.
660 * @cont: function will be called asynchronously when the firmware
661 *	request is over.
662 *
663 *	Asynchronous variant of request_firmware() for user contexts where
664 *	it is not possible to sleep for long time. It can't be called
665 *	in atomic contexts.
 
 
 
 
 
 
666 **/
667int
668request_firmware_nowait(
669	struct module *module, bool uevent,
670	const char *name, struct device *device, gfp_t gfp, void *context,
671	void (*cont)(const struct firmware *fw, void *context))
672{
673	struct task_struct *task;
674	struct firmware_work *fw_work;
675
676	fw_work = kzalloc(sizeof (struct firmware_work), gfp);
677	if (!fw_work)
678		return -ENOMEM;
679
680	fw_work->module = module;
681	fw_work->name = name;
 
 
 
 
682	fw_work->device = device;
683	fw_work->context = context;
684	fw_work->cont = cont;
685	fw_work->uevent = uevent;
 
686
687	if (!try_module_get(module)) {
 
688		kfree(fw_work);
689		return -EFAULT;
690	}
691
692	task = kthread_run(request_firmware_work_func, fw_work,
693			    "firmware/%s", name);
694	if (IS_ERR(task)) {
695		fw_work->cont(NULL, fw_work->context);
696		module_put(fw_work->module);
697		kfree(fw_work);
698		return PTR_ERR(task);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
699	}
700
701	return 0;
702}
703
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
704static int __init firmware_class_init(void)
705{
 
 
 
706	return class_register(&firmware_class);
 
 
 
707}
708
709static void __exit firmware_class_exit(void)
710{
 
 
 
 
 
 
711	class_unregister(&firmware_class);
 
712}
713
714fs_initcall(firmware_class_init);
715module_exit(firmware_class_exit);
716
717EXPORT_SYMBOL(release_firmware);
718EXPORT_SYMBOL(request_firmware);
719EXPORT_SYMBOL(request_firmware_nowait);
v4.10.11
   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/fs.h>
  27#include <linux/async.h>
  28#include <linux/pm.h>
  29#include <linux/suspend.h>
  30#include <linux/syscore_ops.h>
  31#include <linux/reboot.h>
  32#include <linux/security.h>
  33#include <linux/swait.h>
  34
  35#include <generated/utsrelease.h>
  36
  37#include "base.h"
  38
  39MODULE_AUTHOR("Manuel Estrada Sainz");
  40MODULE_DESCRIPTION("Multi purpose firmware loading support");
  41MODULE_LICENSE("GPL");
  42
  43/* Builtin firmware support */
  44
  45#ifdef CONFIG_FW_LOADER
  46
  47extern struct builtin_fw __start_builtin_fw[];
  48extern struct builtin_fw __end_builtin_fw[];
  49
  50static bool fw_get_builtin_firmware(struct firmware *fw, const char *name,
  51				    void *buf, size_t size)
  52{
  53	struct builtin_fw *b_fw;
  54
  55	for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
  56		if (strcmp(name, b_fw->name) == 0) {
  57			fw->size = b_fw->size;
  58			fw->data = b_fw->data;
  59
  60			if (buf && fw->size <= size)
  61				memcpy(buf, fw->data, fw->size);
  62			return true;
  63		}
  64	}
  65
  66	return false;
  67}
  68
  69static bool fw_is_builtin_firmware(const struct firmware *fw)
  70{
  71	struct builtin_fw *b_fw;
  72
  73	for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
  74		if (fw->data == b_fw->data)
  75			return true;
  76
  77	return false;
  78}
  79
  80#else /* Module case - no builtin firmware support */
  81
  82static inline bool fw_get_builtin_firmware(struct firmware *fw,
  83					   const char *name, void *buf,
  84					   size_t size)
  85{
  86	return false;
  87}
  88
  89static inline bool fw_is_builtin_firmware(const struct firmware *fw)
  90{
  91	return false;
  92}
  93#endif
  94
  95enum fw_status {
  96	FW_STATUS_UNKNOWN,
  97	FW_STATUS_LOADING,
  98	FW_STATUS_DONE,
  99	FW_STATUS_ABORTED,
 100};
 101
 102static int loading_timeout = 60;	/* In seconds */
 103
 104static inline long firmware_loading_timeout(void)
 105{
 106	return loading_timeout > 0 ? loading_timeout * HZ : MAX_JIFFY_OFFSET;
 107}
 108
 109/*
 110 * Concurrent request_firmware() for the same firmware need to be
 111 * serialized.  struct fw_state is simple state machine which hold the
 112 * state of the firmware loading.
 113 */
 114struct fw_state {
 115	struct swait_queue_head wq;
 116	enum fw_status status;
 117};
 118
 119static void fw_state_init(struct fw_state *fw_st)
 120{
 121	init_swait_queue_head(&fw_st->wq);
 122	fw_st->status = FW_STATUS_UNKNOWN;
 123}
 124
 125static inline bool __fw_state_is_done(enum fw_status status)
 126{
 127	return status == FW_STATUS_DONE || status == FW_STATUS_ABORTED;
 128}
 129
 130static int __fw_state_wait_common(struct fw_state *fw_st, long timeout)
 131{
 132	long ret;
 133
 134	ret = swait_event_interruptible_timeout(fw_st->wq,
 135				__fw_state_is_done(READ_ONCE(fw_st->status)),
 136				timeout);
 137	if (ret != 0 && fw_st->status == FW_STATUS_ABORTED)
 138		return -ENOENT;
 139	if (!ret)
 140		return -ETIMEDOUT;
 141
 142	return ret < 0 ? ret : 0;
 143}
 144
 145static void __fw_state_set(struct fw_state *fw_st,
 146			   enum fw_status status)
 147{
 148	WRITE_ONCE(fw_st->status, status);
 149
 150	if (status == FW_STATUS_DONE || status == FW_STATUS_ABORTED)
 151		swake_up(&fw_st->wq);
 152}
 153
 154#define fw_state_start(fw_st)					\
 155	__fw_state_set(fw_st, FW_STATUS_LOADING)
 156#define fw_state_done(fw_st)					\
 157	__fw_state_set(fw_st, FW_STATUS_DONE)
 158#define fw_state_wait(fw_st)					\
 159	__fw_state_wait_common(fw_st, MAX_SCHEDULE_TIMEOUT)
 160
 161#ifndef CONFIG_FW_LOADER_USER_HELPER
 162
 163#define fw_state_is_aborted(fw_st)	false
 164
 165#else /* CONFIG_FW_LOADER_USER_HELPER */
 166
 167static int __fw_state_check(struct fw_state *fw_st, enum fw_status status)
 168{
 169	return fw_st->status == status;
 170}
 171
 172#define fw_state_aborted(fw_st)					\
 173	__fw_state_set(fw_st, FW_STATUS_ABORTED)
 174#define fw_state_is_done(fw_st)					\
 175	__fw_state_check(fw_st, FW_STATUS_DONE)
 176#define fw_state_is_loading(fw_st)				\
 177	__fw_state_check(fw_st, FW_STATUS_LOADING)
 178#define fw_state_is_aborted(fw_st)				\
 179	__fw_state_check(fw_st, FW_STATUS_ABORTED)
 180#define fw_state_wait_timeout(fw_st, timeout)			\
 181	__fw_state_wait_common(fw_st, timeout)
 182
 183#endif /* CONFIG_FW_LOADER_USER_HELPER */
 184
 185/* firmware behavior options */
 186#define FW_OPT_UEVENT	(1U << 0)
 187#define FW_OPT_NOWAIT	(1U << 1)
 188#ifdef CONFIG_FW_LOADER_USER_HELPER
 189#define FW_OPT_USERHELPER	(1U << 2)
 190#else
 191#define FW_OPT_USERHELPER	0
 192#endif
 193#ifdef CONFIG_FW_LOADER_USER_HELPER_FALLBACK
 194#define FW_OPT_FALLBACK		FW_OPT_USERHELPER
 195#else
 196#define FW_OPT_FALLBACK		0
 197#endif
 198#define FW_OPT_NO_WARN	(1U << 3)
 199#define FW_OPT_NOCACHE	(1U << 4)
 200
 201struct firmware_cache {
 202	/* firmware_buf instance will be added into the below list */
 203	spinlock_t lock;
 204	struct list_head head;
 205	int state;
 206
 207#ifdef CONFIG_PM_SLEEP
 208	/*
 209	 * Names of firmware images which have been cached successfully
 210	 * will be added into the below list so that device uncache
 211	 * helper can trace which firmware images have been cached
 212	 * before.
 213	 */
 214	spinlock_t name_lock;
 215	struct list_head fw_names;
 216
 217	struct delayed_work work;
 218
 219	struct notifier_block   pm_notify;
 220#endif
 221};
 222
 223struct firmware_buf {
 224	struct kref ref;
 225	struct list_head list;
 226	struct firmware_cache *fwc;
 227	struct fw_state fw_st;
 228	void *data;
 229	size_t size;
 230	size_t allocated_size;
 231#ifdef CONFIG_FW_LOADER_USER_HELPER
 232	bool is_paged_buf;
 233	bool need_uevent;
 234	struct page **pages;
 235	int nr_pages;
 236	int page_array_size;
 237	struct list_head pending_list;
 238#endif
 239	const char *fw_id;
 240};
 241
 242struct fw_cache_entry {
 243	struct list_head list;
 244	const char *name;
 245};
 246
 247struct fw_name_devm {
 248	unsigned long magic;
 249	const char *name;
 250};
 251
 252#define to_fwbuf(d) container_of(d, struct firmware_buf, ref)
 253
 254#define	FW_LOADER_NO_CACHE	0
 255#define	FW_LOADER_START_CACHE	1
 256
 257static int fw_cache_piggyback_on_request(const char *name);
 258
 259/* fw_lock could be moved to 'struct firmware_priv' but since it is just
 260 * guarding for corner cases a global lock should be OK */
 261static DEFINE_MUTEX(fw_lock);
 262
 263static struct firmware_cache fw_cache;
 264
 265static struct firmware_buf *__allocate_fw_buf(const char *fw_name,
 266					      struct firmware_cache *fwc,
 267					      void *dbuf, size_t size)
 268{
 269	struct firmware_buf *buf;
 270
 271	buf = kzalloc(sizeof(*buf), GFP_ATOMIC);
 272	if (!buf)
 273		return NULL;
 274
 275	buf->fw_id = kstrdup_const(fw_name, GFP_ATOMIC);
 276	if (!buf->fw_id) {
 277		kfree(buf);
 278		return NULL;
 279	}
 280
 281	kref_init(&buf->ref);
 282	buf->fwc = fwc;
 283	buf->data = dbuf;
 284	buf->allocated_size = size;
 285	fw_state_init(&buf->fw_st);
 286#ifdef CONFIG_FW_LOADER_USER_HELPER
 287	INIT_LIST_HEAD(&buf->pending_list);
 288#endif
 289
 290	pr_debug("%s: fw-%s buf=%p\n", __func__, fw_name, buf);
 291
 292	return buf;
 293}
 294
 295static struct firmware_buf *__fw_lookup_buf(const char *fw_name)
 296{
 297	struct firmware_buf *tmp;
 298	struct firmware_cache *fwc = &fw_cache;
 299
 300	list_for_each_entry(tmp, &fwc->head, list)
 301		if (!strcmp(tmp->fw_id, fw_name))
 302			return tmp;
 303	return NULL;
 304}
 305
 306static int fw_lookup_and_allocate_buf(const char *fw_name,
 307				      struct firmware_cache *fwc,
 308				      struct firmware_buf **buf, void *dbuf,
 309				      size_t size)
 310{
 311	struct firmware_buf *tmp;
 312
 313	spin_lock(&fwc->lock);
 314	tmp = __fw_lookup_buf(fw_name);
 315	if (tmp) {
 316		kref_get(&tmp->ref);
 317		spin_unlock(&fwc->lock);
 318		*buf = tmp;
 319		return 1;
 320	}
 321	tmp = __allocate_fw_buf(fw_name, fwc, dbuf, size);
 322	if (tmp)
 323		list_add(&tmp->list, &fwc->head);
 324	spin_unlock(&fwc->lock);
 325
 326	*buf = tmp;
 327
 328	return tmp ? 0 : -ENOMEM;
 329}
 330
 331static void __fw_free_buf(struct kref *ref)
 332	__releases(&fwc->lock)
 333{
 334	struct firmware_buf *buf = to_fwbuf(ref);
 335	struct firmware_cache *fwc = buf->fwc;
 336
 337	pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
 338		 __func__, buf->fw_id, buf, buf->data,
 339		 (unsigned int)buf->size);
 340
 341	list_del(&buf->list);
 342	spin_unlock(&fwc->lock);
 343
 344#ifdef CONFIG_FW_LOADER_USER_HELPER
 345	if (buf->is_paged_buf) {
 346		int i;
 347		vunmap(buf->data);
 348		for (i = 0; i < buf->nr_pages; i++)
 349			__free_page(buf->pages[i]);
 350		vfree(buf->pages);
 351	} else
 352#endif
 353	if (!buf->allocated_size)
 354		vfree(buf->data);
 355	kfree_const(buf->fw_id);
 356	kfree(buf);
 357}
 358
 359static void fw_free_buf(struct firmware_buf *buf)
 360{
 361	struct firmware_cache *fwc = buf->fwc;
 362	spin_lock(&fwc->lock);
 363	if (!kref_put(&buf->ref, __fw_free_buf))
 364		spin_unlock(&fwc->lock);
 365}
 366
 367/* direct firmware loading support */
 368static char fw_path_para[256];
 369static const char * const fw_path[] = {
 370	fw_path_para,
 371	"/lib/firmware/updates/" UTS_RELEASE,
 372	"/lib/firmware/updates",
 373	"/lib/firmware/" UTS_RELEASE,
 374	"/lib/firmware"
 375};
 376
 377/*
 378 * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
 379 * from kernel command line because firmware_class is generally built in
 380 * kernel instead of module.
 381 */
 382module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
 383MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
 384
 385static int
 386fw_get_filesystem_firmware(struct device *device, struct firmware_buf *buf)
 387{
 388	loff_t size;
 389	int i, len;
 390	int rc = -ENOENT;
 391	char *path;
 392	enum kernel_read_file_id id = READING_FIRMWARE;
 393	size_t msize = INT_MAX;
 394
 395	/* Already populated data member means we're loading into a buffer */
 396	if (buf->data) {
 397		id = READING_FIRMWARE_PREALLOC_BUFFER;
 398		msize = buf->allocated_size;
 399	}
 400
 401	path = __getname();
 402	if (!path)
 403		return -ENOMEM;
 404
 405	for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
 406		/* skip the unset customized path */
 407		if (!fw_path[i][0])
 408			continue;
 409
 410		len = snprintf(path, PATH_MAX, "%s/%s",
 411			       fw_path[i], buf->fw_id);
 412		if (len >= PATH_MAX) {
 413			rc = -ENAMETOOLONG;
 414			break;
 415		}
 416
 417		buf->size = 0;
 418		rc = kernel_read_file_from_path(path, &buf->data, &size, msize,
 419						id);
 420		if (rc) {
 421			if (rc == -ENOENT)
 422				dev_dbg(device, "loading %s failed with error %d\n",
 423					 path, rc);
 424			else
 425				dev_warn(device, "loading %s failed with error %d\n",
 426					 path, rc);
 427			continue;
 428		}
 429		dev_dbg(device, "direct-loading %s\n", buf->fw_id);
 430		buf->size = size;
 431		fw_state_done(&buf->fw_st);
 432		break;
 433	}
 434	__putname(path);
 435
 436	return rc;
 437}
 438
 439/* firmware holds the ownership of pages */
 440static void firmware_free_data(const struct firmware *fw)
 441{
 442	/* Loaded directly? */
 443	if (!fw->priv) {
 444		vfree(fw->data);
 445		return;
 446	}
 447	fw_free_buf(fw->priv);
 448}
 449
 450/* store the pages buffer info firmware from buf */
 451static void fw_set_page_data(struct firmware_buf *buf, struct firmware *fw)
 452{
 453	fw->priv = buf;
 454#ifdef CONFIG_FW_LOADER_USER_HELPER
 455	fw->pages = buf->pages;
 456#endif
 457	fw->size = buf->size;
 458	fw->data = buf->data;
 459
 460	pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
 461		 __func__, buf->fw_id, buf, buf->data,
 462		 (unsigned int)buf->size);
 463}
 464
 465#ifdef CONFIG_PM_SLEEP
 466static void fw_name_devm_release(struct device *dev, void *res)
 467{
 468	struct fw_name_devm *fwn = res;
 469
 470	if (fwn->magic == (unsigned long)&fw_cache)
 471		pr_debug("%s: fw_name-%s devm-%p released\n",
 472				__func__, fwn->name, res);
 473	kfree_const(fwn->name);
 474}
 475
 476static int fw_devm_match(struct device *dev, void *res,
 477		void *match_data)
 478{
 479	struct fw_name_devm *fwn = res;
 480
 481	return (fwn->magic == (unsigned long)&fw_cache) &&
 482		!strcmp(fwn->name, match_data);
 483}
 484
 485static struct fw_name_devm *fw_find_devm_name(struct device *dev,
 486		const char *name)
 487{
 488	struct fw_name_devm *fwn;
 489
 490	fwn = devres_find(dev, fw_name_devm_release,
 491			  fw_devm_match, (void *)name);
 492	return fwn;
 493}
 494
 495/* add firmware name into devres list */
 496static int fw_add_devm_name(struct device *dev, const char *name)
 497{
 498	struct fw_name_devm *fwn;
 499
 500	fwn = fw_find_devm_name(dev, name);
 501	if (fwn)
 502		return 1;
 503
 504	fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm),
 505			   GFP_KERNEL);
 506	if (!fwn)
 507		return -ENOMEM;
 508	fwn->name = kstrdup_const(name, GFP_KERNEL);
 509	if (!fwn->name) {
 510		devres_free(fwn);
 511		return -ENOMEM;
 512	}
 513
 514	fwn->magic = (unsigned long)&fw_cache;
 515	devres_add(dev, fwn);
 516
 517	return 0;
 518}
 519#else
 520static int fw_add_devm_name(struct device *dev, const char *name)
 521{
 522	return 0;
 523}
 524#endif
 525
 526
 527/*
 528 * user-mode helper code
 529 */
 530#ifdef CONFIG_FW_LOADER_USER_HELPER
 531struct firmware_priv {
 
 
 
 
 
 
 
 
 532	bool nowait;
 533	struct device dev;
 534	struct firmware_buf *buf;
 535	struct firmware *fw;
 536};
 537
 538static struct firmware_priv *to_firmware_priv(struct device *dev)
 539{
 540	return container_of(dev, struct firmware_priv, dev);
 541}
 542
 543static void __fw_load_abort(struct firmware_buf *buf)
 544{
 545	/*
 546	 * There is a small window in which user can write to 'loading'
 547	 * between loading done and disappearance of 'loading'
 548	 */
 549	if (fw_state_is_done(&buf->fw_st))
 550		return;
 551
 552	list_del_init(&buf->pending_list);
 553	fw_state_aborted(&buf->fw_st);
 554}
 555
 556static void fw_load_abort(struct firmware_priv *fw_priv)
 557{
 558	struct firmware_buf *buf = fw_priv->buf;
 559
 560	__fw_load_abort(buf);
 561}
 562
 563static LIST_HEAD(pending_fw_head);
 564
 565/* reboot notifier for avoid deadlock with usermode_lock */
 566static int fw_shutdown_notify(struct notifier_block *unused1,
 567			      unsigned long unused2, void *unused3)
 568{
 569	mutex_lock(&fw_lock);
 570	while (!list_empty(&pending_fw_head))
 571		__fw_load_abort(list_first_entry(&pending_fw_head,
 572					       struct firmware_buf,
 573					       pending_list));
 574	mutex_unlock(&fw_lock);
 575	return NOTIFY_DONE;
 576}
 577
 578static struct notifier_block fw_shutdown_nb = {
 579	.notifier_call = fw_shutdown_notify,
 580};
 581
 582static ssize_t timeout_show(struct class *class, struct class_attribute *attr,
 583			    char *buf)
 584{
 585	return sprintf(buf, "%d\n", loading_timeout);
 586}
 587
 588/**
 589 * firmware_timeout_store - set number of seconds to wait for firmware
 590 * @class: device class pointer
 591 * @attr: device attribute pointer
 592 * @buf: buffer to scan for timeout value
 593 * @count: number of bytes in @buf
 594 *
 595 *	Sets the number of seconds to wait for the firmware.  Once
 596 *	this expires an error will be returned to the driver and no
 597 *	firmware will be provided.
 598 *
 599 *	Note: zero means 'wait forever'.
 600 **/
 601static ssize_t timeout_store(struct class *class, struct class_attribute *attr,
 602			     const char *buf, size_t count)
 
 603{
 604	loading_timeout = simple_strtol(buf, NULL, 10);
 605	if (loading_timeout < 0)
 606		loading_timeout = 0;
 607
 608	return count;
 609}
 610static CLASS_ATTR_RW(timeout);
 611
 612static struct attribute *firmware_class_attrs[] = {
 613	&class_attr_timeout.attr,
 614	NULL,
 
 615};
 616ATTRIBUTE_GROUPS(firmware_class);
 617
 618static void fw_dev_release(struct device *dev)
 619{
 620	struct firmware_priv *fw_priv = to_firmware_priv(dev);
 
 621
 
 
 
 622	kfree(fw_priv);
 
 
 623}
 624
 625static int do_firmware_uevent(struct firmware_priv *fw_priv, struct kobj_uevent_env *env)
 626{
 627	if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->buf->fw_id))
 
 
 628		return -ENOMEM;
 629	if (add_uevent_var(env, "TIMEOUT=%i", loading_timeout))
 630		return -ENOMEM;
 631	if (add_uevent_var(env, "ASYNC=%d", fw_priv->nowait))
 632		return -ENOMEM;
 633
 634	return 0;
 635}
 636
 637static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
 638{
 639	struct firmware_priv *fw_priv = to_firmware_priv(dev);
 640	int err = 0;
 641
 642	mutex_lock(&fw_lock);
 643	if (fw_priv->buf)
 644		err = do_firmware_uevent(fw_priv, env);
 645	mutex_unlock(&fw_lock);
 646	return err;
 647}
 648
 649static struct class firmware_class = {
 650	.name		= "firmware",
 651	.class_groups	= firmware_class_groups,
 652	.dev_uevent	= firmware_uevent,
 653	.dev_release	= fw_dev_release,
 654};
 655
 656static ssize_t firmware_loading_show(struct device *dev,
 657				     struct device_attribute *attr, char *buf)
 658{
 659	struct firmware_priv *fw_priv = to_firmware_priv(dev);
 660	int loading = 0;
 661
 662	mutex_lock(&fw_lock);
 663	if (fw_priv->buf)
 664		loading = fw_state_is_loading(&fw_priv->buf->fw_st);
 665	mutex_unlock(&fw_lock);
 666
 667	return sprintf(buf, "%d\n", loading);
 
 
 
 
 
 
 
 
 668}
 669
 670/* Some architectures don't have PAGE_KERNEL_RO */
 671#ifndef PAGE_KERNEL_RO
 672#define PAGE_KERNEL_RO PAGE_KERNEL
 673#endif
 674
 675/* one pages buffer should be mapped/unmapped only once */
 676static int fw_map_pages_buf(struct firmware_buf *buf)
 677{
 678	if (!buf->is_paged_buf)
 679		return 0;
 680
 681	vunmap(buf->data);
 682	buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);
 683	if (!buf->data)
 684		return -ENOMEM;
 685	return 0;
 686}
 687
 688/**
 689 * firmware_loading_store - set value in the 'loading' control file
 690 * @dev: device pointer
 691 * @attr: device attribute pointer
 692 * @buf: buffer to scan for loading control value
 693 * @count: number of bytes in @buf
 694 *
 695 *	The relevant values are:
 696 *
 697 *	 1: Start a load, discarding any previous partial load.
 698 *	 0: Conclude the load and hand the data to the driver code.
 699 *	-1: Conclude the load with an error and discard any written data.
 700 **/
 701static ssize_t firmware_loading_store(struct device *dev,
 702				      struct device_attribute *attr,
 703				      const char *buf, size_t count)
 704{
 705	struct firmware_priv *fw_priv = to_firmware_priv(dev);
 706	struct firmware_buf *fw_buf;
 707	ssize_t written = count;
 708	int loading = simple_strtol(buf, NULL, 10);
 709	int i;
 710
 711	mutex_lock(&fw_lock);
 712	fw_buf = fw_priv->buf;
 713	if (fw_state_is_aborted(&fw_buf->fw_st))
 714		goto out;
 715
 716	switch (loading) {
 717	case 1:
 718		/* discarding any previous partial load */
 719		if (!fw_state_is_done(&fw_buf->fw_st)) {
 720			for (i = 0; i < fw_buf->nr_pages; i++)
 721				__free_page(fw_buf->pages[i]);
 722			vfree(fw_buf->pages);
 723			fw_buf->pages = NULL;
 724			fw_buf->page_array_size = 0;
 725			fw_buf->nr_pages = 0;
 726			fw_state_start(&fw_buf->fw_st);
 727		}
 
 
 
 
 
 
 
 
 
 
 
 728		break;
 729	case 0:
 730		if (fw_state_is_loading(&fw_buf->fw_st)) {
 731			int rc;
 732
 733			/*
 734			 * Several loading requests may be pending on
 735			 * one same firmware buf, so let all requests
 736			 * see the mapped 'buf->data' once the loading
 737			 * is completed.
 738			 * */
 739			rc = fw_map_pages_buf(fw_buf);
 740			if (rc)
 741				dev_err(dev, "%s: map pages failed\n",
 742					__func__);
 743			else
 744				rc = security_kernel_post_read_file(NULL,
 745						fw_buf->data, fw_buf->size,
 746						READING_FIRMWARE);
 747
 748			/*
 749			 * Same logic as fw_load_abort, only the DONE bit
 750			 * is ignored and we set ABORT only on failure.
 751			 */
 752			list_del_init(&fw_buf->pending_list);
 753			if (rc) {
 754				fw_state_aborted(&fw_buf->fw_st);
 755				written = rc;
 756			} else {
 757				fw_state_done(&fw_buf->fw_st);
 758			}
 
 
 
 
 
 
 
 
 759			break;
 760		}
 761		/* fallthrough */
 762	default:
 763		dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
 764		/* fallthrough */
 765	case -1:
 
 766		fw_load_abort(fw_priv);
 767		break;
 768	}
 769out:
 770	mutex_unlock(&fw_lock);
 771	return written;
 772}
 773
 774static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
 775
 776static void firmware_rw_buf(struct firmware_buf *buf, char *buffer,
 777			   loff_t offset, size_t count, bool read)
 778{
 779	if (read)
 780		memcpy(buffer, buf->data + offset, count);
 781	else
 782		memcpy(buf->data + offset, buffer, count);
 783}
 784
 785static void firmware_rw(struct firmware_buf *buf, char *buffer,
 786			loff_t offset, size_t count, bool read)
 787{
 788	while (count) {
 789		void *page_data;
 790		int page_nr = offset >> PAGE_SHIFT;
 791		int page_ofs = offset & (PAGE_SIZE-1);
 792		int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 793
 794		page_data = kmap(buf->pages[page_nr]);
 795
 796		if (read)
 797			memcpy(buffer, page_data + page_ofs, page_cnt);
 798		else
 799			memcpy(page_data + page_ofs, buffer, page_cnt);
 800
 801		kunmap(buf->pages[page_nr]);
 802		buffer += page_cnt;
 803		offset += page_cnt;
 804		count -= page_cnt;
 805	}
 806}
 807
 808static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
 809				  struct bin_attribute *bin_attr,
 810				  char *buffer, loff_t offset, size_t count)
 811{
 812	struct device *dev = kobj_to_dev(kobj);
 813	struct firmware_priv *fw_priv = to_firmware_priv(dev);
 814	struct firmware_buf *buf;
 815	ssize_t ret_count;
 816
 817	mutex_lock(&fw_lock);
 818	buf = fw_priv->buf;
 819	if (!buf || fw_state_is_done(&buf->fw_st)) {
 820		ret_count = -ENODEV;
 821		goto out;
 822	}
 823	if (offset > buf->size) {
 824		ret_count = 0;
 825		goto out;
 826	}
 827	if (count > buf->size - offset)
 828		count = buf->size - offset;
 829
 830	ret_count = count;
 831
 832	if (buf->data)
 833		firmware_rw_buf(buf, buffer, offset, count, true);
 834	else
 835		firmware_rw(buf, buffer, offset, count, true);
 
 
 
 
 
 836
 
 
 
 
 
 837out:
 838	mutex_unlock(&fw_lock);
 839	return ret_count;
 840}
 841
 842static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
 843{
 844	struct firmware_buf *buf = fw_priv->buf;
 845	int pages_needed = PAGE_ALIGN(min_size) >> PAGE_SHIFT;
 846
 847	/* If the array of pages is too small, grow it... */
 848	if (buf->page_array_size < pages_needed) {
 849		int new_array_size = max(pages_needed,
 850					 buf->page_array_size * 2);
 851		struct page **new_pages;
 852
 853		new_pages = vmalloc(new_array_size * sizeof(void *));
 
 854		if (!new_pages) {
 855			fw_load_abort(fw_priv);
 856			return -ENOMEM;
 857		}
 858		memcpy(new_pages, buf->pages,
 859		       buf->page_array_size * sizeof(void *));
 860		memset(&new_pages[buf->page_array_size], 0, sizeof(void *) *
 861		       (new_array_size - buf->page_array_size));
 862		vfree(buf->pages);
 863		buf->pages = new_pages;
 864		buf->page_array_size = new_array_size;
 865	}
 866
 867	while (buf->nr_pages < pages_needed) {
 868		buf->pages[buf->nr_pages] =
 869			alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
 870
 871		if (!buf->pages[buf->nr_pages]) {
 872			fw_load_abort(fw_priv);
 873			return -ENOMEM;
 874		}
 875		buf->nr_pages++;
 876	}
 877	return 0;
 878}
 879
 880/**
 881 * firmware_data_write - write method for firmware
 882 * @filp: open sysfs file
 883 * @kobj: kobject for the device
 884 * @bin_attr: bin_attr structure
 885 * @buffer: buffer being written
 886 * @offset: buffer offset for write in total data store area
 887 * @count: buffer size
 888 *
 889 *	Data written to the 'data' attribute will be later handed to
 890 *	the driver as a firmware image.
 891 **/
 892static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
 893				   struct bin_attribute *bin_attr,
 894				   char *buffer, loff_t offset, size_t count)
 895{
 896	struct device *dev = kobj_to_dev(kobj);
 897	struct firmware_priv *fw_priv = to_firmware_priv(dev);
 898	struct firmware_buf *buf;
 899	ssize_t retval;
 900
 901	if (!capable(CAP_SYS_RAWIO))
 902		return -EPERM;
 903
 904	mutex_lock(&fw_lock);
 905	buf = fw_priv->buf;
 906	if (!buf || fw_state_is_done(&buf->fw_st)) {
 907		retval = -ENODEV;
 908		goto out;
 909	}
 
 
 
 
 
 
 
 
 
 
 
 910
 911	if (buf->data) {
 912		if (offset + count > buf->allocated_size) {
 913			retval = -ENOMEM;
 914			goto out;
 915		}
 916		firmware_rw_buf(buf, buffer, offset, count, false);
 917		retval = count;
 918	} else {
 919		retval = fw_realloc_buffer(fw_priv, offset + count);
 920		if (retval)
 921			goto out;
 922
 923		retval = count;
 924		firmware_rw(buf, buffer, offset, count, false);
 
 
 925	}
 926
 927	buf->size = max_t(size_t, offset + count, buf->size);
 928out:
 929	mutex_unlock(&fw_lock);
 930	return retval;
 931}
 932
 933static struct bin_attribute firmware_attr_data = {
 934	.attr = { .name = "data", .mode = 0644 },
 935	.size = 0,
 936	.read = firmware_data_read,
 937	.write = firmware_data_write,
 938};
 939
 940static struct attribute *fw_dev_attrs[] = {
 941	&dev_attr_loading.attr,
 942	NULL
 943};
 944
 945static struct bin_attribute *fw_dev_bin_attrs[] = {
 946	&firmware_attr_data,
 947	NULL
 948};
 949
 950static const struct attribute_group fw_dev_attr_group = {
 951	.attrs = fw_dev_attrs,
 952	.bin_attrs = fw_dev_bin_attrs,
 953};
 954
 955static const struct attribute_group *fw_dev_attr_groups[] = {
 956	&fw_dev_attr_group,
 957	NULL
 958};
 959
 960static struct firmware_priv *
 961fw_create_instance(struct firmware *firmware, const char *fw_name,
 962		   struct device *device, unsigned int opt_flags)
 963{
 964	struct firmware_priv *fw_priv;
 965	struct device *f_dev;
 
 966
 967	fw_priv = kzalloc(sizeof(*fw_priv), GFP_KERNEL);
 968	if (!fw_priv) {
 969		fw_priv = ERR_PTR(-ENOMEM);
 970		goto exit;
 
 971	}
 972
 973	fw_priv->nowait = !!(opt_flags & FW_OPT_NOWAIT);
 974	fw_priv->fw = firmware;
 
 
 
 
 
 
 975	f_dev = &fw_priv->dev;
 976
 977	device_initialize(f_dev);
 978	dev_set_name(f_dev, "%s", fw_name);
 979	f_dev->parent = device;
 980	f_dev->class = &firmware_class;
 981	f_dev->groups = fw_dev_attr_groups;
 982exit:
 983	return fw_priv;
 984}
 985
 986/* load a firmware via user helper */
 987static int _request_firmware_load(struct firmware_priv *fw_priv,
 988				  unsigned int opt_flags, long timeout)
 989{
 990	int retval = 0;
 991	struct device *f_dev = &fw_priv->dev;
 992	struct firmware_buf *buf = fw_priv->buf;
 993
 994	/* fall back on userspace loading */
 995	if (!buf->data)
 996		buf->is_paged_buf = true;
 997
 998	dev_set_uevent_suppress(f_dev, true);
 999
1000	retval = device_add(f_dev);
1001	if (retval) {
1002		dev_err(f_dev, "%s: device_register failed\n", __func__);
1003		goto err_put_dev;
1004	}
1005
1006	mutex_lock(&fw_lock);
1007	list_add(&buf->pending_list, &pending_fw_head);
1008	mutex_unlock(&fw_lock);
 
 
1009
1010	if (opt_flags & FW_OPT_UEVENT) {
1011		buf->need_uevent = true;
1012		dev_set_uevent_suppress(f_dev, false);
1013		dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id);
1014		kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
1015	} else {
1016		timeout = MAX_JIFFY_OFFSET;
1017	}
1018
1019	retval = fw_state_wait_timeout(&buf->fw_st, timeout);
1020	if (retval < 0) {
1021		mutex_lock(&fw_lock);
1022		fw_load_abort(fw_priv);
1023		mutex_unlock(&fw_lock);
1024	}
1025
1026	if (fw_state_is_aborted(&buf->fw_st))
1027		retval = -EAGAIN;
1028	else if (buf->is_paged_buf && !buf->data)
1029		retval = -ENOMEM;
1030
 
 
 
1031	device_del(f_dev);
1032err_put_dev:
1033	put_device(f_dev);
1034	return retval;
 
1035}
1036
1037static int fw_load_from_user_helper(struct firmware *firmware,
1038				    const char *name, struct device *device,
1039				    unsigned int opt_flags, long timeout)
1040{
1041	struct firmware_priv *fw_priv;
1042
1043	fw_priv = fw_create_instance(firmware, name, device, opt_flags);
1044	if (IS_ERR(fw_priv))
1045		return PTR_ERR(fw_priv);
1046
1047	fw_priv->buf = firmware->priv;
1048	return _request_firmware_load(fw_priv, opt_flags, timeout);
1049}
1050
1051#ifdef CONFIG_PM_SLEEP
1052/* kill pending requests without uevent to avoid blocking suspend */
1053static void kill_requests_without_uevent(void)
1054{
1055	struct firmware_buf *buf;
1056	struct firmware_buf *next;
 
1057
1058	mutex_lock(&fw_lock);
1059	list_for_each_entry_safe(buf, next, &pending_fw_head, pending_list) {
1060		if (!buf->need_uevent)
1061			 __fw_load_abort(buf);
1062	}
1063	mutex_unlock(&fw_lock);
1064}
1065#endif
1066
1067#else /* CONFIG_FW_LOADER_USER_HELPER */
1068static inline int
1069fw_load_from_user_helper(struct firmware *firmware, const char *name,
1070			 struct device *device, unsigned int opt_flags,
1071			 long timeout)
1072{
1073	return -ENOENT;
1074}
1075
1076#ifdef CONFIG_PM_SLEEP
1077static inline void kill_requests_without_uevent(void) { }
1078#endif
1079
1080#endif /* CONFIG_FW_LOADER_USER_HELPER */
1081
1082/* prepare firmware and firmware_buf structs;
1083 * return 0 if a firmware is already assigned, 1 if need to load one,
1084 * or a negative error code
1085 */
1086static int
1087_request_firmware_prepare(struct firmware **firmware_p, const char *name,
1088			  struct device *device, void *dbuf, size_t size)
1089{
1090	struct firmware *firmware;
1091	struct firmware_buf *buf;
1092	int ret;
1093
1094	*firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
1095	if (!firmware) {
1096		dev_err(device, "%s: kmalloc(struct firmware) failed\n",
1097			__func__);
1098		return -ENOMEM;
 
1099	}
1100
1101	if (fw_get_builtin_firmware(firmware, name, dbuf, size)) {
1102		dev_dbg(device, "using built-in %s\n", name);
1103		return 0; /* assigned */
1104	}
1105
1106	ret = fw_lookup_and_allocate_buf(name, &fw_cache, &buf, dbuf, size);
1107
1108	/*
1109	 * bind with 'buf' now to avoid warning in failure path
1110	 * of requesting firmware.
1111	 */
1112	firmware->priv = buf;
1113
1114	if (ret > 0) {
1115		ret = fw_state_wait(&buf->fw_st);
1116		if (!ret) {
1117			fw_set_page_data(buf, firmware);
1118			return 0; /* assigned */
1119		}
1120	}
1121
1122	if (ret < 0)
1123		return ret;
1124	return 1; /* need to load */
1125}
1126
1127static int assign_firmware_buf(struct firmware *fw, struct device *device,
1128			       unsigned int opt_flags)
1129{
1130	struct firmware_buf *buf = fw->priv;
1131
1132	mutex_lock(&fw_lock);
1133	if (!buf->size || fw_state_is_aborted(&buf->fw_st)) {
1134		mutex_unlock(&fw_lock);
1135		return -ENOENT;
1136	}
1137
1138	/*
1139	 * add firmware name into devres list so that we can auto cache
1140	 * and uncache firmware for device.
1141	 *
1142	 * device may has been deleted already, but the problem
1143	 * should be fixed in devres or driver core.
1144	 */
1145	/* don't cache firmware handled without uevent */
1146	if (device && (opt_flags & FW_OPT_UEVENT) &&
1147	    !(opt_flags & FW_OPT_NOCACHE))
1148		fw_add_devm_name(device, buf->fw_id);
1149
1150	/*
1151	 * After caching firmware image is started, let it piggyback
1152	 * on request firmware.
1153	 */
1154	if (!(opt_flags & FW_OPT_NOCACHE) &&
1155	    buf->fwc->state == FW_LOADER_START_CACHE) {
1156		if (fw_cache_piggyback_on_request(buf->fw_id))
1157			kref_get(&buf->ref);
1158	}
1159
1160	/* pass the pages buffer to driver at the last minute */
1161	fw_set_page_data(buf, fw);
1162	mutex_unlock(&fw_lock);
1163	return 0;
1164}
1165
1166/* called from request_firmware() and request_firmware_work_func() */
1167static int
1168_request_firmware(const struct firmware **firmware_p, const char *name,
1169		  struct device *device, void *buf, size_t size,
1170		  unsigned int opt_flags)
1171{
1172	struct firmware *fw = NULL;
1173	long timeout;
1174	int ret;
1175
1176	if (!firmware_p)
1177		return -EINVAL;
1178
1179	if (!name || name[0] == '\0') {
1180		ret = -EINVAL;
 
1181		goto out;
1182	}
1183
1184	ret = _request_firmware_prepare(&fw, name, device, buf, size);
1185	if (ret <= 0) /* error or already assigned */
1186		goto out;
 
 
1187
1188	ret = 0;
1189	timeout = firmware_loading_timeout();
1190	if (opt_flags & FW_OPT_NOWAIT) {
1191		timeout = usermodehelper_read_lock_wait(timeout);
1192		if (!timeout) {
1193			dev_dbg(device, "firmware: %s loading timed out\n",
1194				name);
1195			ret = -EBUSY;
1196			goto out;
1197		}
1198	} else {
1199		ret = usermodehelper_read_trylock();
1200		if (WARN_ON(ret)) {
1201			dev_err(device, "firmware: %s will not be loaded\n",
1202				name);
1203			goto out;
1204		}
1205	}
1206
1207	ret = fw_get_filesystem_firmware(device, fw->priv);
1208	if (ret) {
1209		if (!(opt_flags & FW_OPT_NO_WARN))
1210			dev_warn(device,
1211				 "Direct firmware load for %s failed with error %d\n",
1212				 name, ret);
1213		if (opt_flags & FW_OPT_USERHELPER) {
1214			dev_warn(device, "Falling back to user helper\n");
1215			ret = fw_load_from_user_helper(fw, name, device,
1216						       opt_flags, timeout);
1217		}
1218	}
1219
1220	if (!ret)
1221		ret = assign_firmware_buf(fw, device, opt_flags);
 
 
 
1222
1223	usermodehelper_read_unlock();
1224
1225 out:
1226	if (ret < 0) {
1227		release_firmware(fw);
1228		fw = NULL;
1229	}
1230
1231	*firmware_p = fw;
1232	return ret;
1233}
1234
1235/**
1236 * request_firmware: - send firmware request and wait for it
1237 * @firmware_p: pointer to firmware image
1238 * @name: name of firmware file
1239 * @device: device for which firmware is being loaded
1240 *
1241 *      @firmware_p will be used to return a firmware image by the name
1242 *      of @name for device @device.
1243 *
1244 *      Should be called from user context where sleeping is allowed.
1245 *
1246 *      @name will be used as $FIRMWARE in the uevent environment and
1247 *      should be distinctive enough not to be confused with any other
1248 *      firmware image for this or any other device.
1249 *
1250 *	Caller must hold the reference count of @device.
1251 *
1252 *	The function can be called safely inside device's suspend and
1253 *	resume callback.
1254 **/
1255int
1256request_firmware(const struct firmware **firmware_p, const char *name,
1257		 struct device *device)
1258{
1259	int ret;
1260
1261	/* Need to pin this module until return */
1262	__module_get(THIS_MODULE);
1263	ret = _request_firmware(firmware_p, name, device, NULL, 0,
1264				FW_OPT_UEVENT | FW_OPT_FALLBACK);
1265	module_put(THIS_MODULE);
1266	return ret;
1267}
1268EXPORT_SYMBOL(request_firmware);
1269
1270/**
1271 * request_firmware_direct: - load firmware directly without usermode helper
1272 * @firmware_p: pointer to firmware image
1273 * @name: name of firmware file
1274 * @device: device for which firmware is being loaded
1275 *
1276 * This function works pretty much like request_firmware(), but this doesn't
1277 * fall back to usermode helper even if the firmware couldn't be loaded
1278 * directly from fs.  Hence it's useful for loading optional firmwares, which
1279 * aren't always present, without extra long timeouts of udev.
1280 **/
1281int request_firmware_direct(const struct firmware **firmware_p,
1282			    const char *name, struct device *device)
1283{
1284	int ret;
1285
1286	__module_get(THIS_MODULE);
1287	ret = _request_firmware(firmware_p, name, device, NULL, 0,
1288				FW_OPT_UEVENT | FW_OPT_NO_WARN);
1289	module_put(THIS_MODULE);
1290	return ret;
1291}
1292EXPORT_SYMBOL_GPL(request_firmware_direct);
1293
1294/**
1295 * request_firmware_into_buf - load firmware into a previously allocated buffer
1296 * @firmware_p: pointer to firmware image
1297 * @name: name of firmware file
1298 * @device: device for which firmware is being loaded and DMA region allocated
1299 * @buf: address of buffer to load firmware into
1300 * @size: size of buffer
1301 *
1302 * This function works pretty much like request_firmware(), but it doesn't
1303 * allocate a buffer to hold the firmware data. Instead, the firmware
1304 * is loaded directly into the buffer pointed to by @buf and the @firmware_p
1305 * data member is pointed at @buf.
1306 *
1307 * This function doesn't cache firmware either.
1308 */
1309int
1310request_firmware_into_buf(const struct firmware **firmware_p, const char *name,
1311			  struct device *device, void *buf, size_t size)
1312{
1313	int ret;
1314
1315	__module_get(THIS_MODULE);
1316	ret = _request_firmware(firmware_p, name, device, buf, size,
1317				FW_OPT_UEVENT | FW_OPT_FALLBACK |
1318				FW_OPT_NOCACHE);
1319	module_put(THIS_MODULE);
1320	return ret;
1321}
1322EXPORT_SYMBOL(request_firmware_into_buf);
1323
1324/**
1325 * release_firmware: - release the resource associated with a firmware image
1326 * @fw: firmware resource to release
1327 **/
1328void release_firmware(const struct firmware *fw)
1329{
1330	if (fw) {
1331		if (!fw_is_builtin_firmware(fw))
1332			firmware_free_data(fw);
1333		kfree(fw);
1334	}
1335}
1336EXPORT_SYMBOL(release_firmware);
1337
1338/* Async support */
1339struct firmware_work {
1340	struct work_struct work;
1341	struct module *module;
1342	const char *name;
1343	struct device *device;
1344	void *context;
1345	void (*cont)(const struct firmware *fw, void *context);
1346	unsigned int opt_flags;
1347};
1348
1349static void request_firmware_work_func(struct work_struct *work)
1350{
1351	struct firmware_work *fw_work;
1352	const struct firmware *fw;
 
1353
1354	fw_work = container_of(work, struct firmware_work, work);
 
 
 
1355
1356	_request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0,
1357			  fw_work->opt_flags);
1358	fw_work->cont(fw, fw_work->context);
1359	put_device(fw_work->device); /* taken in request_firmware_nowait() */
1360
1361	module_put(fw_work->module);
1362	kfree_const(fw_work->name);
1363	kfree(fw_work);
 
 
1364}
1365
1366/**
1367 * request_firmware_nowait - asynchronous version of request_firmware
1368 * @module: module requesting the firmware
1369 * @uevent: sends uevent to copy the firmware image if this flag
1370 *	is non-zero else the firmware copy must be done manually.
1371 * @name: name of firmware file
1372 * @device: device for which firmware is being loaded
1373 * @gfp: allocation flags
1374 * @context: will be passed over to @cont, and
1375 *	@fw may be %NULL if firmware request fails.
1376 * @cont: function will be called asynchronously when the firmware
1377 *	request is over.
1378 *
1379 *	Caller must hold the reference count of @device.
1380 *
1381 *	Asynchronous variant of request_firmware() for user contexts:
1382 *		- sleep for as small periods as possible since it may
1383 *		  increase kernel boot time of built-in device drivers
1384 *		  requesting firmware in their ->probe() methods, if
1385 *		  @gfp is GFP_KERNEL.
1386 *
1387 *		- can't sleep at all if @gfp is GFP_ATOMIC.
1388 **/
1389int
1390request_firmware_nowait(
1391	struct module *module, bool uevent,
1392	const char *name, struct device *device, gfp_t gfp, void *context,
1393	void (*cont)(const struct firmware *fw, void *context))
1394{
 
1395	struct firmware_work *fw_work;
1396
1397	fw_work = kzalloc(sizeof(struct firmware_work), gfp);
1398	if (!fw_work)
1399		return -ENOMEM;
1400
1401	fw_work->module = module;
1402	fw_work->name = kstrdup_const(name, gfp);
1403	if (!fw_work->name) {
1404		kfree(fw_work);
1405		return -ENOMEM;
1406	}
1407	fw_work->device = device;
1408	fw_work->context = context;
1409	fw_work->cont = cont;
1410	fw_work->opt_flags = FW_OPT_NOWAIT | FW_OPT_FALLBACK |
1411		(uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
1412
1413	if (!try_module_get(module)) {
1414		kfree_const(fw_work->name);
1415		kfree(fw_work);
1416		return -EFAULT;
1417	}
1418
1419	get_device(fw_work->device);
1420	INIT_WORK(&fw_work->work, request_firmware_work_func);
1421	schedule_work(&fw_work->work);
1422	return 0;
1423}
1424EXPORT_SYMBOL(request_firmware_nowait);
1425
1426#ifdef CONFIG_PM_SLEEP
1427static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1428
1429/**
1430 * cache_firmware - cache one firmware image in kernel memory space
1431 * @fw_name: the firmware image name
1432 *
1433 * Cache firmware in kernel memory so that drivers can use it when
1434 * system isn't ready for them to request firmware image from userspace.
1435 * Once it returns successfully, driver can use request_firmware or its
1436 * nowait version to get the cached firmware without any interacting
1437 * with userspace
1438 *
1439 * Return 0 if the firmware image has been cached successfully
1440 * Return !0 otherwise
1441 *
1442 */
1443static int cache_firmware(const char *fw_name)
1444{
1445	int ret;
1446	const struct firmware *fw;
1447
1448	pr_debug("%s: %s\n", __func__, fw_name);
1449
1450	ret = request_firmware(&fw, fw_name, NULL);
1451	if (!ret)
1452		kfree(fw);
1453
1454	pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1455
1456	return ret;
1457}
1458
1459static struct firmware_buf *fw_lookup_buf(const char *fw_name)
1460{
1461	struct firmware_buf *tmp;
1462	struct firmware_cache *fwc = &fw_cache;
1463
1464	spin_lock(&fwc->lock);
1465	tmp = __fw_lookup_buf(fw_name);
1466	spin_unlock(&fwc->lock);
1467
1468	return tmp;
1469}
1470
1471/**
1472 * uncache_firmware - remove one cached firmware image
1473 * @fw_name: the firmware image name
1474 *
1475 * Uncache one firmware image which has been cached successfully
1476 * before.
1477 *
1478 * Return 0 if the firmware cache has been removed successfully
1479 * Return !0 otherwise
1480 *
1481 */
1482static int uncache_firmware(const char *fw_name)
1483{
1484	struct firmware_buf *buf;
1485	struct firmware fw;
1486
1487	pr_debug("%s: %s\n", __func__, fw_name);
1488
1489	if (fw_get_builtin_firmware(&fw, fw_name, NULL, 0))
1490		return 0;
1491
1492	buf = fw_lookup_buf(fw_name);
1493	if (buf) {
1494		fw_free_buf(buf);
1495		return 0;
1496	}
1497
1498	return -EINVAL;
1499}
1500
1501static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1502{
1503	struct fw_cache_entry *fce;
1504
1505	fce = kzalloc(sizeof(*fce), GFP_ATOMIC);
1506	if (!fce)
1507		goto exit;
1508
1509	fce->name = kstrdup_const(name, GFP_ATOMIC);
1510	if (!fce->name) {
1511		kfree(fce);
1512		fce = NULL;
1513		goto exit;
1514	}
1515exit:
1516	return fce;
1517}
1518
1519static int __fw_entry_found(const char *name)
1520{
1521	struct firmware_cache *fwc = &fw_cache;
1522	struct fw_cache_entry *fce;
1523
1524	list_for_each_entry(fce, &fwc->fw_names, list) {
1525		if (!strcmp(fce->name, name))
1526			return 1;
1527	}
1528	return 0;
1529}
1530
1531static int fw_cache_piggyback_on_request(const char *name)
1532{
1533	struct firmware_cache *fwc = &fw_cache;
1534	struct fw_cache_entry *fce;
1535	int ret = 0;
1536
1537	spin_lock(&fwc->name_lock);
1538	if (__fw_entry_found(name))
1539		goto found;
1540
1541	fce = alloc_fw_cache_entry(name);
1542	if (fce) {
1543		ret = 1;
1544		list_add(&fce->list, &fwc->fw_names);
1545		pr_debug("%s: fw: %s\n", __func__, name);
1546	}
1547found:
1548	spin_unlock(&fwc->name_lock);
1549	return ret;
1550}
1551
1552static void free_fw_cache_entry(struct fw_cache_entry *fce)
1553{
1554	kfree_const(fce->name);
1555	kfree(fce);
1556}
1557
1558static void __async_dev_cache_fw_image(void *fw_entry,
1559				       async_cookie_t cookie)
1560{
1561	struct fw_cache_entry *fce = fw_entry;
1562	struct firmware_cache *fwc = &fw_cache;
1563	int ret;
1564
1565	ret = cache_firmware(fce->name);
1566	if (ret) {
1567		spin_lock(&fwc->name_lock);
1568		list_del(&fce->list);
1569		spin_unlock(&fwc->name_lock);
1570
1571		free_fw_cache_entry(fce);
1572	}
1573}
1574
1575/* called with dev->devres_lock held */
1576static void dev_create_fw_entry(struct device *dev, void *res,
1577				void *data)
1578{
1579	struct fw_name_devm *fwn = res;
1580	const char *fw_name = fwn->name;
1581	struct list_head *head = data;
1582	struct fw_cache_entry *fce;
1583
1584	fce = alloc_fw_cache_entry(fw_name);
1585	if (fce)
1586		list_add(&fce->list, head);
1587}
1588
1589static int devm_name_match(struct device *dev, void *res,
1590			   void *match_data)
1591{
1592	struct fw_name_devm *fwn = res;
1593	return (fwn->magic == (unsigned long)match_data);
1594}
1595
1596static void dev_cache_fw_image(struct device *dev, void *data)
1597{
1598	LIST_HEAD(todo);
1599	struct fw_cache_entry *fce;
1600	struct fw_cache_entry *fce_next;
1601	struct firmware_cache *fwc = &fw_cache;
1602
1603	devres_for_each_res(dev, fw_name_devm_release,
1604			    devm_name_match, &fw_cache,
1605			    dev_create_fw_entry, &todo);
1606
1607	list_for_each_entry_safe(fce, fce_next, &todo, list) {
1608		list_del(&fce->list);
1609
1610		spin_lock(&fwc->name_lock);
1611		/* only one cache entry for one firmware */
1612		if (!__fw_entry_found(fce->name)) {
1613			list_add(&fce->list, &fwc->fw_names);
1614		} else {
1615			free_fw_cache_entry(fce);
1616			fce = NULL;
1617		}
1618		spin_unlock(&fwc->name_lock);
1619
1620		if (fce)
1621			async_schedule_domain(__async_dev_cache_fw_image,
1622					      (void *)fce,
1623					      &fw_cache_domain);
1624	}
1625}
1626
1627static void __device_uncache_fw_images(void)
1628{
1629	struct firmware_cache *fwc = &fw_cache;
1630	struct fw_cache_entry *fce;
1631
1632	spin_lock(&fwc->name_lock);
1633	while (!list_empty(&fwc->fw_names)) {
1634		fce = list_entry(fwc->fw_names.next,
1635				struct fw_cache_entry, list);
1636		list_del(&fce->list);
1637		spin_unlock(&fwc->name_lock);
1638
1639		uncache_firmware(fce->name);
1640		free_fw_cache_entry(fce);
1641
1642		spin_lock(&fwc->name_lock);
1643	}
1644	spin_unlock(&fwc->name_lock);
1645}
1646
1647/**
1648 * device_cache_fw_images - cache devices' firmware
1649 *
1650 * If one device called request_firmware or its nowait version
1651 * successfully before, the firmware names are recored into the
1652 * device's devres link list, so device_cache_fw_images can call
1653 * cache_firmware() to cache these firmwares for the device,
1654 * then the device driver can load its firmwares easily at
1655 * time when system is not ready to complete loading firmware.
1656 */
1657static void device_cache_fw_images(void)
1658{
1659	struct firmware_cache *fwc = &fw_cache;
1660	int old_timeout;
1661	DEFINE_WAIT(wait);
1662
1663	pr_debug("%s\n", __func__);
1664
1665	/* cancel uncache work */
1666	cancel_delayed_work_sync(&fwc->work);
1667
1668	/*
1669	 * use small loading timeout for caching devices' firmware
1670	 * because all these firmware images have been loaded
1671	 * successfully at lease once, also system is ready for
1672	 * completing firmware loading now. The maximum size of
1673	 * firmware in current distributions is about 2M bytes,
1674	 * so 10 secs should be enough.
1675	 */
1676	old_timeout = loading_timeout;
1677	loading_timeout = 10;
1678
1679	mutex_lock(&fw_lock);
1680	fwc->state = FW_LOADER_START_CACHE;
1681	dpm_for_each_dev(NULL, dev_cache_fw_image);
1682	mutex_unlock(&fw_lock);
1683
1684	/* wait for completion of caching firmware for all devices */
1685	async_synchronize_full_domain(&fw_cache_domain);
1686
1687	loading_timeout = old_timeout;
1688}
1689
1690/**
1691 * device_uncache_fw_images - uncache devices' firmware
1692 *
1693 * uncache all firmwares which have been cached successfully
1694 * by device_uncache_fw_images earlier
1695 */
1696static void device_uncache_fw_images(void)
1697{
1698	pr_debug("%s\n", __func__);
1699	__device_uncache_fw_images();
1700}
1701
1702static void device_uncache_fw_images_work(struct work_struct *work)
1703{
1704	device_uncache_fw_images();
1705}
1706
1707/**
1708 * device_uncache_fw_images_delay - uncache devices firmwares
1709 * @delay: number of milliseconds to delay uncache device firmwares
1710 *
1711 * uncache all devices's firmwares which has been cached successfully
1712 * by device_cache_fw_images after @delay milliseconds.
1713 */
1714static void device_uncache_fw_images_delay(unsigned long delay)
1715{
1716	queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1717			   msecs_to_jiffies(delay));
1718}
1719
1720static int fw_pm_notify(struct notifier_block *notify_block,
1721			unsigned long mode, void *unused)
1722{
1723	switch (mode) {
1724	case PM_HIBERNATION_PREPARE:
1725	case PM_SUSPEND_PREPARE:
1726	case PM_RESTORE_PREPARE:
1727		kill_requests_without_uevent();
1728		device_cache_fw_images();
1729		break;
1730
1731	case PM_POST_SUSPEND:
1732	case PM_POST_HIBERNATION:
1733	case PM_POST_RESTORE:
1734		/*
1735		 * In case that system sleep failed and syscore_suspend is
1736		 * not called.
1737		 */
1738		mutex_lock(&fw_lock);
1739		fw_cache.state = FW_LOADER_NO_CACHE;
1740		mutex_unlock(&fw_lock);
1741
1742		device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1743		break;
1744	}
1745
1746	return 0;
1747}
1748
1749/* stop caching firmware once syscore_suspend is reached */
1750static int fw_suspend(void)
1751{
1752	fw_cache.state = FW_LOADER_NO_CACHE;
1753	return 0;
1754}
1755
1756static struct syscore_ops fw_syscore_ops = {
1757	.suspend = fw_suspend,
1758};
1759#else
1760static int fw_cache_piggyback_on_request(const char *name)
1761{
1762	return 0;
1763}
1764#endif
1765
1766static void __init fw_cache_init(void)
1767{
1768	spin_lock_init(&fw_cache.lock);
1769	INIT_LIST_HEAD(&fw_cache.head);
1770	fw_cache.state = FW_LOADER_NO_CACHE;
1771
1772#ifdef CONFIG_PM_SLEEP
1773	spin_lock_init(&fw_cache.name_lock);
1774	INIT_LIST_HEAD(&fw_cache.fw_names);
1775
1776	INIT_DELAYED_WORK(&fw_cache.work,
1777			  device_uncache_fw_images_work);
1778
1779	fw_cache.pm_notify.notifier_call = fw_pm_notify;
1780	register_pm_notifier(&fw_cache.pm_notify);
1781
1782	register_syscore_ops(&fw_syscore_ops);
1783#endif
1784}
1785
1786static int __init firmware_class_init(void)
1787{
1788	fw_cache_init();
1789#ifdef CONFIG_FW_LOADER_USER_HELPER
1790	register_reboot_notifier(&fw_shutdown_nb);
1791	return class_register(&firmware_class);
1792#else
1793	return 0;
1794#endif
1795}
1796
1797static void __exit firmware_class_exit(void)
1798{
1799#ifdef CONFIG_PM_SLEEP
1800	unregister_syscore_ops(&fw_syscore_ops);
1801	unregister_pm_notifier(&fw_cache.pm_notify);
1802#endif
1803#ifdef CONFIG_FW_LOADER_USER_HELPER
1804	unregister_reboot_notifier(&fw_shutdown_nb);
1805	class_unregister(&firmware_class);
1806#endif
1807}
1808
1809fs_initcall(firmware_class_init);
1810module_exit(firmware_class_exit);