53 static int hwrng_init(struct hwrng *rng);
56 static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size,
64 static void add_early_randomness(struct hwrng *rng)  in add_early_randomness()  argument
69 	bytes_read = rng_get_data(rng, rng_fillbuf, 32, 0);  in add_early_randomness()
72 		size_t entropy = bytes_read * 8 * rng->quality / 1024;  in add_early_randomness()
79 	struct hwrng *rng = container_of(kref, struct hwrng, ref);  in cleanup_rng()  local
81 	if (rng->cleanup)  in cleanup_rng()
82 		rng->cleanup(rng);  in cleanup_rng()
84 	complete(&rng->cleanup_done);  in cleanup_rng()
87 static int set_current_rng(struct hwrng *rng)  in set_current_rng()  argument
93 	err = hwrng_init(rng);  in set_current_rng()
98 	current_rng = rng;  in set_current_rng()
134 	struct hwrng *rng;  in get_current_rng()  local
139 	rng = get_current_rng_nolock();  in get_current_rng()
142 	return rng;  in get_current_rng()
145 static void put_rng(struct hwrng *rng)  in put_rng()  argument
152 	if (rng)  in put_rng()
153 		kref_put(&rng->ref, cleanup_rng);  in put_rng()
157 static int hwrng_init(struct hwrng *rng)  in hwrng_init()  argument
159 	if (kref_get_unless_zero(&rng->ref))  in hwrng_init()
162 	if (rng->init) {  in hwrng_init()
165 		ret =  rng->init(rng);  in hwrng_init()
170 	kref_init(&rng->ref);  in hwrng_init()
171 	reinit_completion(&rng->cleanup_done);  in hwrng_init()
174 	rng->quality = min_t(u16, min_t(u16, default_quality, 1024), rng->quality ?: 1024);  in hwrng_init()
175 	current_quality = rng->quality; /* obsolete */  in hwrng_init()
190 static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size,  in rng_get_data()  argument
195 	if (rng->read)  in rng_get_data()
196 		return rng->read(rng, (void *)buffer, size, wait);  in rng_get_data()
198 	if (rng->data_present)  in rng_get_data()
199 		present = rng->data_present(rng, wait);  in rng_get_data()
204 		return rng->data_read(rng, (u32 *)buffer);  in rng_get_data()
215 	struct hwrng *rng;  in rng_dev_read()  local
218 		rng = get_current_rng();  in rng_dev_read()
219 		if (IS_ERR(rng)) {  in rng_dev_read()
220 			err = PTR_ERR(rng);  in rng_dev_read()
223 		if (!rng) {  in rng_dev_read()
233 			bytes_read = rng_get_data(rng, rng_buffer,  in rng_dev_read()
266 		put_rng(rng);  in rng_dev_read()
282 	put_rng(rng);  in rng_dev_read()
305 	struct hwrng *rng, *new_rng = NULL;  in enable_best_rng()  local
318 	list_for_each_entry(rng, &rng_list, list) {  in enable_best_rng()
319 		if (!new_rng || rng->quality > new_rng->quality)  in enable_best_rng()
320 			new_rng = rng;  in enable_best_rng()
335 	struct hwrng *rng, *old_rng, *new_rng;  in rng_current_store()  local
345 		list_for_each_entry(rng, &rng_list, list) {  in rng_current_store()
346 			if (sysfs_streq(rng->name, buf)) {  in rng_current_store()
347 				err = set_current_rng(rng);  in rng_current_store()
371 	struct hwrng *rng;  in rng_current_show()  local
373 	rng = get_current_rng();  in rng_current_show()
374 	if (IS_ERR(rng))  in rng_current_show()
375 		return PTR_ERR(rng);  in rng_current_show()
377 	ret = snprintf(buf, PAGE_SIZE, "%s\n", rng ? rng->name : "none");  in rng_current_show()
378 	put_rng(rng);  in rng_current_show()
388 	struct hwrng *rng;  in rng_available_show()  local
394 	list_for_each_entry(rng, &rng_list, list) {  in rng_available_show()
395 		strlcat(buf, rng->name, PAGE_SIZE);  in rng_available_show()
416 	struct hwrng *rng;  in rng_quality_show()  local
418 	rng = get_current_rng();  in rng_quality_show()
419 	if (IS_ERR(rng))  in rng_quality_show()
420 		return PTR_ERR(rng);  in rng_quality_show()
422 	if (!rng) /* no need to put_rng */  in rng_quality_show()
425 	ret = sysfs_emit(buf, "%hu\n", rng->quality);  in rng_quality_show()
426 	put_rng(rng);  in rng_quality_show()
499 		struct hwrng *rng;  in hwrng_fillfn()  local
501 		rng = get_current_rng();  in hwrng_fillfn()
502 		if (IS_ERR(rng) || !rng)  in hwrng_fillfn()
505 		rc = rng_get_data(rng, rng_fillbuf,  in hwrng_fillfn()
507 		if (current_quality != rng->quality)  in hwrng_fillfn()
508 			rng->quality = current_quality; /* obsolete */  in hwrng_fillfn()
509 		quality = rng->quality;  in hwrng_fillfn()
513 			hwrng_msleep(rng, 10000);  in hwrng_fillfn()
515 		put_rng(rng);  in hwrng_fillfn()
535 int hwrng_register(struct hwrng *rng)  in hwrng_register()  argument
541 	if (!rng->name || (!rng->data_read && !rng->read))  in hwrng_register()
549 		if (strcmp(tmp->name, rng->name) == 0)  in hwrng_register()
552 	list_add_tail(&rng->list, &rng_list);  in hwrng_register()
554 	init_completion(&rng->cleanup_done);  in hwrng_register()
555 	complete(&rng->cleanup_done);  in hwrng_register()
556 	init_completion(&rng->dying);  in hwrng_register()
559 	    (!cur_rng_set_by_user && rng->quality > current_rng->quality)) {  in hwrng_register()
565 		err = set_current_rng(rng);  in hwrng_register()
572 		kref_get(&rng->ref);  in hwrng_register()
575 	if (is_new_current || !rng->init) {  in hwrng_register()
583 		add_early_randomness(rng);  in hwrng_register()
586 		put_rng(rng);  in hwrng_register()
595 void hwrng_unregister(struct hwrng *rng)  in hwrng_unregister()  argument
603 	list_del(&rng->list);  in hwrng_unregister()
604 	complete_all(&rng->dying);  in hwrng_unregister()
605 	if (current_rng == rng) {  in hwrng_unregister()
627 	wait_for_completion(&rng->cleanup_done);  in hwrng_unregister()
646 int devm_hwrng_register(struct device *dev, struct hwrng *rng)  in devm_hwrng_register()  argument
655 	error = hwrng_register(rng);  in devm_hwrng_register()
661 	*ptr = rng;  in devm_hwrng_register()
667 void devm_hwrng_unregister(struct device *dev, struct hwrng *rng)  in devm_hwrng_unregister()  argument
669 	devres_release(dev, devm_hwrng_release, devm_hwrng_match, rng);  in devm_hwrng_unregister()
673 long hwrng_msleep(struct hwrng *rng, unsigned int msecs)  in hwrng_msleep()  argument
677 	return wait_for_completion_interruptible_timeout(&rng->dying, timeout);  in hwrng_msleep()