1929 lines · 45.8 KB · C
RawDownload
/* * firmware_class.c - Multi purpose firmware loading support * * Copyright (c) 2003 Manuel Estrada Sainz * * Please see Documentation/firmware_class/ for more information. * */ #include <linux/capability.h>#include <linux/device.h>#include <linux/module.h>#include <linux/init.h>#include <linux/timer.h>#include <linux/vmalloc.h>#include <linux/interrupt.h>#include <linux/bitops.h>#include <linux/mutex.h>#include <linux/workqueue.h>#include <linux/highmem.h>#include <linux/firmware.h>#include <linux/slab.h>#include <linux/sched.h>#include <linux/file.h>#include <linux/list.h>#include <linux/fs.h>#include <linux/async.h>#include <linux/pm.h>#include <linux/suspend.h>#include <linux/syscore_ops.h>#include <linux/reboot.h>#include <linux/security.h> #include <generated/utsrelease.h> #include "base.h" MODULE_AUTHOR("Manuel Estrada Sainz");MODULE_DESCRIPTION("Multi purpose firmware loading support");MODULE_LICENSE("GPL"); /* Builtin firmware support */ #ifdef CONFIG_FW_LOADER extern struct builtin_fw __start_builtin_fw[];extern struct builtin_fw __end_builtin_fw[]; static bool fw_get_builtin_firmware(struct firmware *fw, const char *name,				    void *buf, size_t size){	struct builtin_fw *b_fw; 	for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {		if (strcmp(name, b_fw->name) == 0) {			fw->size = b_fw->size;			fw->data = b_fw->data; 			if (buf && fw->size <= size)				memcpy(buf, fw->data, fw->size);			return true;		}	} 	return false;} static bool fw_is_builtin_firmware(const struct firmware *fw){	struct builtin_fw *b_fw; 	for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)		if (fw->data == b_fw->data)			return true; 	return false;} #else /* Module case - no builtin firmware support */ static inline bool fw_get_builtin_firmware(struct firmware *fw,					   const char *name, void *buf,					   size_t size){	return false;} static inline bool fw_is_builtin_firmware(const struct firmware *fw){	return false;}#endif enum fw_status {	FW_STATUS_UNKNOWN,	FW_STATUS_LOADING,	FW_STATUS_DONE,	FW_STATUS_ABORTED,}; static int loading_timeout = 60;	/* In seconds */ static inline long firmware_loading_timeout(void){	return loading_timeout > 0 ? loading_timeout * HZ : MAX_JIFFY_OFFSET;} /* * Concurrent request_firmware() for the same firmware need to be * serialized.  struct fw_state is simple state machine which hold the * state of the firmware loading. */struct fw_state {	struct completion completion;	enum fw_status status;}; static void fw_state_init(struct fw_state *fw_st){	init_completion(&fw_st->completion);	fw_st->status = FW_STATUS_UNKNOWN;} static inline bool __fw_state_is_done(enum fw_status status){	return status == FW_STATUS_DONE || status == FW_STATUS_ABORTED;} static int __fw_state_wait_common(struct fw_state *fw_st, long timeout){	long ret; 	ret = wait_for_completion_killable_timeout(&fw_st->completion, timeout);	if (ret != 0 && fw_st->status == FW_STATUS_ABORTED)		return -ENOENT;	if (!ret)		return -ETIMEDOUT; 	return ret < 0 ? ret : 0;} static void __fw_state_set(struct fw_state *fw_st,			   enum fw_status status){	WRITE_ONCE(fw_st->status, status); 	if (status == FW_STATUS_DONE || status == FW_STATUS_ABORTED)		complete_all(&fw_st->completion);} #define fw_state_start(fw_st)					\	__fw_state_set(fw_st, FW_STATUS_LOADING)#define fw_state_done(fw_st)					\	__fw_state_set(fw_st, FW_STATUS_DONE)#define fw_state_aborted(fw_st)					\	__fw_state_set(fw_st, FW_STATUS_ABORTED)#define fw_state_wait(fw_st)					\	__fw_state_wait_common(fw_st, MAX_SCHEDULE_TIMEOUT) static int __fw_state_check(struct fw_state *fw_st, enum fw_status status){	return fw_st->status == status;} #define fw_state_is_aborted(fw_st)				\	__fw_state_check(fw_st, FW_STATUS_ABORTED) #ifdef CONFIG_FW_LOADER_USER_HELPER #define fw_state_aborted(fw_st)					\	__fw_state_set(fw_st, FW_STATUS_ABORTED)#define fw_state_is_done(fw_st)					\	__fw_state_check(fw_st, FW_STATUS_DONE)#define fw_state_is_loading(fw_st)				\	__fw_state_check(fw_st, FW_STATUS_LOADING)#define fw_state_wait_timeout(fw_st, timeout)			\	__fw_state_wait_common(fw_st, timeout) #endif /* CONFIG_FW_LOADER_USER_HELPER */ /* firmware behavior options */#define FW_OPT_UEVENT	(1U << 0)#define FW_OPT_NOWAIT	(1U << 1)#ifdef CONFIG_FW_LOADER_USER_HELPER#define FW_OPT_USERHELPER	(1U << 2)#else#define FW_OPT_USERHELPER	0#endif#ifdef CONFIG_FW_LOADER_USER_HELPER_FALLBACK#define FW_OPT_FALLBACK		FW_OPT_USERHELPER#else#define FW_OPT_FALLBACK		0#endif#define FW_OPT_NO_WARN	(1U << 3)#define FW_OPT_NOCACHE	(1U << 4) struct firmware_cache {	/* firmware_buf instance will be added into the below list */	spinlock_t lock;	struct list_head head;	int state; #ifdef CONFIG_PM_SLEEP	/*	 * Names of firmware images which have been cached successfully	 * will be added into the below list so that device uncache	 * helper can trace which firmware images have been cached	 * before.	 */	spinlock_t name_lock;	struct list_head fw_names; 	struct delayed_work work; 	struct notifier_block   pm_notify;#endif}; struct firmware_buf {	struct kref ref;	struct list_head list;	struct firmware_cache *fwc;	struct fw_state fw_st;	void *data;	size_t size;	size_t allocated_size;#ifdef CONFIG_FW_LOADER_USER_HELPER	bool is_paged_buf;	bool need_uevent;	struct page **pages;	int nr_pages;	int page_array_size;	struct list_head pending_list;#endif	const char *fw_id;}; struct fw_cache_entry {	struct list_head list;	const char *name;}; struct fw_name_devm {	unsigned long magic;	const char *name;}; #define to_fwbuf(d) container_of(d, struct firmware_buf, ref) #define	FW_LOADER_NO_CACHE	0#define	FW_LOADER_START_CACHE	1 static int fw_cache_piggyback_on_request(const char *name); /* fw_lock could be moved to 'struct firmware_priv' but since it is just * guarding for corner cases a global lock should be OK */static DEFINE_MUTEX(fw_lock); static bool __enable_firmware = false; static void enable_firmware(void){	mutex_lock(&fw_lock);	__enable_firmware = true;	mutex_unlock(&fw_lock);} static void disable_firmware(void){	mutex_lock(&fw_lock);	__enable_firmware = false;	mutex_unlock(&fw_lock);} /* * When disabled only the built-in firmware and the firmware cache will be * used to look for firmware. */static bool firmware_enabled(void){	bool enabled = false; 	mutex_lock(&fw_lock);	if (__enable_firmware)		enabled = true;	mutex_unlock(&fw_lock); 	return enabled;} static struct firmware_cache fw_cache; static struct firmware_buf *__allocate_fw_buf(const char *fw_name,					      struct firmware_cache *fwc,					      void *dbuf, size_t size){	struct firmware_buf *buf; 	buf = kzalloc(sizeof(*buf), GFP_ATOMIC);	if (!buf)		return NULL; 	buf->fw_id = kstrdup_const(fw_name, GFP_ATOMIC);	if (!buf->fw_id) {		kfree(buf);		return NULL;	} 	kref_init(&buf->ref);	buf->fwc = fwc;	buf->data = dbuf;	buf->allocated_size = size;	fw_state_init(&buf->fw_st);#ifdef CONFIG_FW_LOADER_USER_HELPER	INIT_LIST_HEAD(&buf->pending_list);#endif 	pr_debug("%s: fw-%s buf=%p\n", __func__, fw_name, buf); 	return buf;} static struct firmware_buf *__fw_lookup_buf(const char *fw_name){	struct firmware_buf *tmp;	struct firmware_cache *fwc = &fw_cache; 	list_for_each_entry(tmp, &fwc->head, list)		if (!strcmp(tmp->fw_id, fw_name))			return tmp;	return NULL;} static int fw_lookup_and_allocate_buf(const char *fw_name,				      struct firmware_cache *fwc,				      struct firmware_buf **buf, void *dbuf,				      size_t size){	struct firmware_buf *tmp; 	spin_lock(&fwc->lock);	tmp = __fw_lookup_buf(fw_name);	if (tmp) {		kref_get(&tmp->ref);		spin_unlock(&fwc->lock);		*buf = tmp;		return 1;	}	tmp = __allocate_fw_buf(fw_name, fwc, dbuf, size);	if (tmp)		list_add(&tmp->list, &fwc->head);	spin_unlock(&fwc->lock); 	*buf = tmp; 	return tmp ? 0 : -ENOMEM;} static void __fw_free_buf(struct kref *ref)	__releases(&fwc->lock){	struct firmware_buf *buf = to_fwbuf(ref);	struct firmware_cache *fwc = buf->fwc; 	pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",		 __func__, buf->fw_id, buf, buf->data,		 (unsigned int)buf->size); 	list_del(&buf->list);	spin_unlock(&fwc->lock); #ifdef CONFIG_FW_LOADER_USER_HELPER	if (buf->is_paged_buf) {		int i;		vunmap(buf->data);		for (i = 0; i < buf->nr_pages; i++)			__free_page(buf->pages[i]);		vfree(buf->pages);	} else#endif	if (!buf->allocated_size)		vfree(buf->data);	kfree_const(buf->fw_id);	kfree(buf);} static void fw_free_buf(struct firmware_buf *buf){	struct firmware_cache *fwc = buf->fwc;	spin_lock(&fwc->lock);	if (!kref_put(&buf->ref, __fw_free_buf))		spin_unlock(&fwc->lock);} /* direct firmware loading support */static char fw_path_para[256];static const char * const fw_path[] = {	fw_path_para,	"/lib/firmware/updates/" UTS_RELEASE,	"/lib/firmware/updates",	"/lib/firmware/" UTS_RELEASE,	"/lib/firmware"}; /* * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH' * from kernel command line because firmware_class is generally built in * kernel instead of module. */module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path"); static intfw_get_filesystem_firmware(struct device *device, struct firmware_buf *buf){	loff_t size;	int i, len;	int rc = -ENOENT;	char *path;	enum kernel_read_file_id id = READING_FIRMWARE;	size_t msize = INT_MAX; 	/* Already populated data member means we're loading into a buffer */	if (buf->data) {		id = READING_FIRMWARE_PREALLOC_BUFFER;		msize = buf->allocated_size;	} 	path = __getname();	if (!path)		return -ENOMEM; 	for (i = 0; i < ARRAY_SIZE(fw_path); i++) {		/* skip the unset customized path */		if (!fw_path[i][0])			continue; 		len = snprintf(path, PATH_MAX, "%s/%s",			       fw_path[i], buf->fw_id);		if (len >= PATH_MAX) {			rc = -ENAMETOOLONG;			break;		} 		buf->size = 0;		rc = kernel_read_file_from_path(path, &buf->data, &size, msize,						id);		if (rc) {			if (rc == -ENOENT)				dev_dbg(device, "loading %s failed with error %d\n",					 path, rc);			else				dev_warn(device, "loading %s failed with error %d\n",					 path, rc);			continue;		}		dev_dbg(device, "direct-loading %s\n", buf->fw_id);		buf->size = size;		fw_state_done(&buf->fw_st);		break;	}	__putname(path); 	return rc;} /* firmware holds the ownership of pages */static void firmware_free_data(const struct firmware *fw){	/* Loaded directly? */	if (!fw->priv) {		vfree(fw->data);		return;	}	fw_free_buf(fw->priv);} /* store the pages buffer info firmware from buf */static void fw_set_page_data(struct firmware_buf *buf, struct firmware *fw){	fw->priv = buf;#ifdef CONFIG_FW_LOADER_USER_HELPER	fw->pages = buf->pages;#endif	fw->size = buf->size;	fw->data = buf->data; 	pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",		 __func__, buf->fw_id, buf, buf->data,		 (unsigned int)buf->size);} #ifdef CONFIG_PM_SLEEPstatic void fw_name_devm_release(struct device *dev, void *res){	struct fw_name_devm *fwn = res; 	if (fwn->magic == (unsigned long)&fw_cache)		pr_debug("%s: fw_name-%s devm-%p released\n",				__func__, fwn->name, res);

Lines 1–500 of 1929.