core.c 37.8 KB
Newer Older
L
Linus Torvalds 已提交
1 2 3 4 5
/*
 * drivers/base/core.c - core driver model code (device registration, etc)
 *
 * Copyright (c) 2002-3 Patrick Mochel
 * Copyright (c) 2002-3 Open Source Development Labs
6 7
 * Copyright (c) 2006 Greg Kroah-Hartman <gregkh@suse.de>
 * Copyright (c) 2006 Novell, Inc.
L
Linus Torvalds 已提交
8 9 10 11 12 13 14 15 16 17 18
 *
 * This file is released under the GPLv2
 *
 */

#include <linux/device.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/string.h>
19
#include <linux/kdev_t.h>
20
#include <linux/notifier.h>
21
#include <linux/genhd.h>
22
#include <linux/kallsyms.h>
23
#include <linux/semaphore.h>
24
#include <linux/mutex.h>
L
Linus Torvalds 已提交
25 26 27 28

#include "base.h"
#include "power/power.h"

29 30
int (*platform_notify)(struct device *dev) = NULL;
int (*platform_notify_remove)(struct device *dev) = NULL;
31 32 33
static struct kobject *dev_kobj;
struct kobject *sysfs_dev_char_kobj;
struct kobject *sysfs_dev_block_kobj;
L
Linus Torvalds 已提交
34

35 36 37 38 39 40 41 42 43 44 45
#ifdef CONFIG_BLOCK
static inline int device_is_not_partition(struct device *dev)
{
	return !(dev->type == &part_type);
}
#else
static inline int device_is_not_partition(struct device *dev)
{
	return 1;
}
#endif
L
Linus Torvalds 已提交
46

47 48 49 50 51 52 53 54 55
/**
 * dev_driver_string - Return a device's driver name, if at all possible
 * @dev: struct device to get the name of
 *
 * Will return the device's driver's name if it is bound to a device.  If
 * the device is not bound to a device, it will return the name of the bus
 * it is attached to.  If it is not attached to a bus either, an empty
 * string will be returned.
 */
56
const char *dev_driver_string(const struct device *dev)
57 58
{
	return dev->driver ? dev->driver->name :
59 60
			(dev->bus ? dev->bus->name :
			(dev->class ? dev->class->name : ""));
61
}
M
Matthew Wilcox 已提交
62
EXPORT_SYMBOL(dev_driver_string);
63

L
Linus Torvalds 已提交
64 65 66
#define to_dev(obj) container_of(obj, struct device, kobj)
#define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr)

67 68
static ssize_t dev_attr_show(struct kobject *kobj, struct attribute *attr,
			     char *buf)
L
Linus Torvalds 已提交
69
{
70 71
	struct device_attribute *dev_attr = to_dev_attr(attr);
	struct device *dev = to_dev(kobj);
72
	ssize_t ret = -EIO;
L
Linus Torvalds 已提交
73 74

	if (dev_attr->show)
75
		ret = dev_attr->show(dev, dev_attr, buf);
76 77 78 79
	if (ret >= (ssize_t)PAGE_SIZE) {
		print_symbol("dev_attr_show: %s returned bad count\n",
				(unsigned long)dev_attr->show);
	}
L
Linus Torvalds 已提交
80 81 82
	return ret;
}

83 84
static ssize_t dev_attr_store(struct kobject *kobj, struct attribute *attr,
			      const char *buf, size_t count)
L
Linus Torvalds 已提交
85
{
86 87
	struct device_attribute *dev_attr = to_dev_attr(attr);
	struct device *dev = to_dev(kobj);
88
	ssize_t ret = -EIO;
L
Linus Torvalds 已提交
89 90

	if (dev_attr->store)
91
		ret = dev_attr->store(dev, dev_attr, buf, count);
L
Linus Torvalds 已提交
92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108
	return ret;
}

static struct sysfs_ops dev_sysfs_ops = {
	.show	= dev_attr_show,
	.store	= dev_attr_store,
};


/**
 *	device_release - free device structure.
 *	@kobj:	device's kobject.
 *
 *	This is called once the reference count for the object
 *	reaches 0. We forward the call to the device's release
 *	method, which should handle actually freeing the structure.
 */
109
static void device_release(struct kobject *kobj)
L
Linus Torvalds 已提交
110
{
111
	struct device *dev = to_dev(kobj);
L
Linus Torvalds 已提交
112 113 114

	if (dev->release)
		dev->release(dev);
115 116
	else if (dev->type && dev->type->release)
		dev->type->release(dev);
117 118
	else if (dev->class && dev->class->dev_release)
		dev->class->dev_release(dev);
A
Arjan van de Ven 已提交
119 120
	else
		WARN(1, KERN_ERR "Device '%s' does not have a release() "
121
			"function, it is broken and must be fixed.\n",
L
Linus Torvalds 已提交
122 123 124
			dev->bus_id);
}

125
static struct kobj_type device_ktype = {
L
Linus Torvalds 已提交
126 127 128 129 130
	.release	= device_release,
	.sysfs_ops	= &dev_sysfs_ops,
};


131
static int dev_uevent_filter(struct kset *kset, struct kobject *kobj)
L
Linus Torvalds 已提交
132 133 134
{
	struct kobj_type *ktype = get_ktype(kobj);

135
	if (ktype == &device_ktype) {
L
Linus Torvalds 已提交
136
		struct device *dev = to_dev(kobj);
137 138
		if (dev->uevent_suppress)
			return 0;
L
Linus Torvalds 已提交
139 140
		if (dev->bus)
			return 1;
141 142
		if (dev->class)
			return 1;
L
Linus Torvalds 已提交
143 144 145 146
	}
	return 0;
}

147
static const char *dev_uevent_name(struct kset *kset, struct kobject *kobj)
L
Linus Torvalds 已提交
148 149 150
{
	struct device *dev = to_dev(kobj);

151 152 153 154 155
	if (dev->bus)
		return dev->bus->name;
	if (dev->class)
		return dev->class->name;
	return NULL;
L
Linus Torvalds 已提交
156 157
}

158 159
static int dev_uevent(struct kset *kset, struct kobject *kobj,
		      struct kobj_uevent_env *env)
L
Linus Torvalds 已提交
160 161 162 163
{
	struct device *dev = to_dev(kobj);
	int retval = 0;

164 165
	/* add the major/minor if present */
	if (MAJOR(dev->devt)) {
166 167
		add_uevent_var(env, "MAJOR=%u", MAJOR(dev->devt));
		add_uevent_var(env, "MINOR=%u", MINOR(dev->devt));
168 169
	}

170
	if (dev->type && dev->type->name)
171
		add_uevent_var(env, "DEVTYPE=%s", dev->type->name);
172

173
	if (dev->driver)
174
		add_uevent_var(env, "DRIVER=%s", dev->driver->name);
175

176
#ifdef CONFIG_SYSFS_DEPRECATED
177 178 179 180 181 182 183 184 185 186
	if (dev->class) {
		struct device *parent = dev->parent;

		/* find first bus device in parent chain */
		while (parent && !parent->bus)
			parent = parent->parent;
		if (parent && parent->bus) {
			const char *path;

			path = kobject_get_path(&parent->kobj, GFP_KERNEL);
187
			if (path) {
188
				add_uevent_var(env, "PHYSDEVPATH=%s", path);
189 190
				kfree(path);
			}
191

192
			add_uevent_var(env, "PHYSDEVBUS=%s", parent->bus->name);
193 194

			if (parent->driver)
195 196
				add_uevent_var(env, "PHYSDEVDRIVER=%s",
					       parent->driver->name);
197 198
		}
	} else if (dev->bus) {
199
		add_uevent_var(env, "PHYSDEVBUS=%s", dev->bus->name);
200 201

		if (dev->driver)
202 203
			add_uevent_var(env, "PHYSDEVDRIVER=%s",
				       dev->driver->name);
K
Kay Sievers 已提交
204
	}
205
#endif
L
Linus Torvalds 已提交
206

207
	/* have the bus specific function add its stuff */
208
	if (dev->bus && dev->bus->uevent) {
209
		retval = dev->bus->uevent(dev, env);
210
		if (retval)
211
			pr_debug("device: '%s': %s: bus uevent() returned %d\n",
212
				 dev->bus_id, __func__, retval);
L
Linus Torvalds 已提交
213 214
	}

215
	/* have the class specific function add its stuff */
216
	if (dev->class && dev->class->dev_uevent) {
217
		retval = dev->class->dev_uevent(dev, env);
218
		if (retval)
219 220
			pr_debug("device: '%s': %s: class uevent() "
				 "returned %d\n", dev->bus_id,
221
				 __func__, retval);
222 223
	}

224
	/* have the device type specific fuction add its stuff */
225
	if (dev->type && dev->type->uevent) {
226
		retval = dev->type->uevent(dev, env);
227
		if (retval)
228 229
			pr_debug("device: '%s': %s: dev_type uevent() "
				 "returned %d\n", dev->bus_id,
230
				 __func__, retval);
231 232
	}

L
Linus Torvalds 已提交
233 234 235
	return retval;
}

236 237 238 239
static struct kset_uevent_ops device_uevent_ops = {
	.filter =	dev_uevent_filter,
	.name =		dev_uevent_name,
	.uevent =	dev_uevent,
L
Linus Torvalds 已提交
240 241
};

242 243 244 245 246
static ssize_t show_uevent(struct device *dev, struct device_attribute *attr,
			   char *buf)
{
	struct kobject *top_kobj;
	struct kset *kset;
247
	struct kobj_uevent_env *env = NULL;
248 249 250 251 252 253
	int i;
	size_t count = 0;
	int retval;

	/* search the kset, the device belongs to */
	top_kobj = &dev->kobj;
254 255
	while (!top_kobj->kset && top_kobj->parent)
		top_kobj = top_kobj->parent;
256 257
	if (!top_kobj->kset)
		goto out;
258

259 260 261 262 263 264 265 266 267
	kset = top_kobj->kset;
	if (!kset->uevent_ops || !kset->uevent_ops->uevent)
		goto out;

	/* respect filter */
	if (kset->uevent_ops && kset->uevent_ops->filter)
		if (!kset->uevent_ops->filter(kset, &dev->kobj))
			goto out;

268 269
	env = kzalloc(sizeof(struct kobj_uevent_env), GFP_KERNEL);
	if (!env)
270 271
		return -ENOMEM;

272
	/* let the kset specific function add its keys */
273
	retval = kset->uevent_ops->uevent(kset, &dev->kobj, env);
274 275 276 277
	if (retval)
		goto out;

	/* copy keys to file */
278 279
	for (i = 0; i < env->envp_idx; i++)
		count += sprintf(&buf[count], "%s\n", env->envp[i]);
280
out:
281
	kfree(env);
282 283 284
	return count;
}

285 286 287
static ssize_t store_uevent(struct device *dev, struct device_attribute *attr,
			    const char *buf, size_t count)
{
288 289
	enum kobject_action action;

290
	if (kobject_action_type(buf, count, &action) == 0) {
291 292 293 294 295 296
		kobject_uevent(&dev->kobj, action);
		goto out;
	}

	dev_err(dev, "uevent: unsupported action-string; this will "
		     "be ignored in a future kernel version\n");
297
	kobject_uevent(&dev->kobj, KOBJ_ADD);
298
out:
299 300 301
	return count;
}

302 303 304
static struct device_attribute uevent_attr =
	__ATTR(uevent, S_IRUGO | S_IWUSR, show_uevent, store_uevent);

305 306
static int device_add_attributes(struct device *dev,
				 struct device_attribute *attrs)
307
{
308
	int error = 0;
309
	int i;
310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336

	if (attrs) {
		for (i = 0; attr_name(attrs[i]); i++) {
			error = device_create_file(dev, &attrs[i]);
			if (error)
				break;
		}
		if (error)
			while (--i >= 0)
				device_remove_file(dev, &attrs[i]);
	}
	return error;
}

static void device_remove_attributes(struct device *dev,
				     struct device_attribute *attrs)
{
	int i;

	if (attrs)
		for (i = 0; attr_name(attrs[i]); i++)
			device_remove_file(dev, &attrs[i]);
}

static int device_add_groups(struct device *dev,
			     struct attribute_group **groups)
{
337
	int error = 0;
338
	int i;
339

340 341 342
	if (groups) {
		for (i = 0; groups[i]; i++) {
			error = sysfs_create_group(&dev->kobj, groups[i]);
343 344
			if (error) {
				while (--i >= 0)
345 346
					sysfs_remove_group(&dev->kobj,
							   groups[i]);
347
				break;
348 349 350 351 352 353
			}
		}
	}
	return error;
}

354 355
static void device_remove_groups(struct device *dev,
				 struct attribute_group **groups)
356 357
{
	int i;
358 359 360 361

	if (groups)
		for (i = 0; groups[i]; i++)
			sysfs_remove_group(&dev->kobj, groups[i]);
362 363
}

364 365 366
static int device_add_attrs(struct device *dev)
{
	struct class *class = dev->class;
367
	struct device_type *type = dev->type;
368
	int error;
369

370 371
	if (class) {
		error = device_add_attributes(dev, class->dev_attrs);
372
		if (error)
373
			return error;
374
	}
375

376 377
	if (type) {
		error = device_add_groups(dev, type->groups);
378
		if (error)
379
			goto err_remove_class_attrs;
380 381
	}

382 383 384 385 386 387 388 389 390 391 392 393 394
	error = device_add_groups(dev, dev->groups);
	if (error)
		goto err_remove_type_groups;

	return 0;

 err_remove_type_groups:
	if (type)
		device_remove_groups(dev, type->groups);
 err_remove_class_attrs:
	if (class)
		device_remove_attributes(dev, class->dev_attrs);

395 396 397 398 399 400
	return error;
}

static void device_remove_attrs(struct device *dev)
{
	struct class *class = dev->class;
401
	struct device_type *type = dev->type;
402

403
	device_remove_groups(dev, dev->groups);
404

405 406 407 408 409
	if (type)
		device_remove_groups(dev, type->groups);

	if (class)
		device_remove_attributes(dev, class->dev_attrs);
410 411 412
}


413 414 415 416 417 418
static ssize_t show_dev(struct device *dev, struct device_attribute *attr,
			char *buf)
{
	return print_dev_t(buf, dev->devt);
}

419 420 421
static struct device_attribute devt_attr =
	__ATTR(dev, S_IRUGO, show_dev, NULL);

422 423
/* kset to create /sys/devices/  */
struct kset *devices_kset;
L
Linus Torvalds 已提交
424 425

/**
426 427 428
 * device_create_file - create sysfs attribute file for device.
 * @dev: device.
 * @attr: device attribute descriptor.
L
Linus Torvalds 已提交
429
 */
430
int device_create_file(struct device *dev, struct device_attribute *attr)
L
Linus Torvalds 已提交
431 432
{
	int error = 0;
433
	if (dev)
L
Linus Torvalds 已提交
434 435 436 437 438
		error = sysfs_create_file(&dev->kobj, &attr->attr);
	return error;
}

/**
439 440 441
 * device_remove_file - remove sysfs attribute file.
 * @dev: device.
 * @attr: device attribute descriptor.
L
Linus Torvalds 已提交
442
 */
443
void device_remove_file(struct device *dev, struct device_attribute *attr)
L
Linus Torvalds 已提交
444
{
445
	if (dev)
L
Linus Torvalds 已提交
446 447 448
		sysfs_remove_file(&dev->kobj, &attr->attr);
}

449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474
/**
 * device_create_bin_file - create sysfs binary attribute file for device.
 * @dev: device.
 * @attr: device binary attribute descriptor.
 */
int device_create_bin_file(struct device *dev, struct bin_attribute *attr)
{
	int error = -EINVAL;
	if (dev)
		error = sysfs_create_bin_file(&dev->kobj, attr);
	return error;
}
EXPORT_SYMBOL_GPL(device_create_bin_file);

/**
 * device_remove_bin_file - remove sysfs binary attribute file
 * @dev: device.
 * @attr: device binary attribute descriptor.
 */
void device_remove_bin_file(struct device *dev, struct bin_attribute *attr)
{
	if (dev)
		sysfs_remove_bin_file(&dev->kobj, attr);
}
EXPORT_SYMBOL_GPL(device_remove_bin_file);

475
/**
476
 * device_schedule_callback_owner - helper to schedule a callback for a device
477 478
 * @dev: device.
 * @func: callback function to invoke later.
479
 * @owner: module owning the callback routine
480 481 482 483 484 485 486 487 488 489
 *
 * Attribute methods must not unregister themselves or their parent device
 * (which would amount to the same thing).  Attempts to do so will deadlock,
 * since unregistration is mutually exclusive with driver callbacks.
 *
 * Instead methods can call this routine, which will attempt to allocate
 * and schedule a workqueue request to call back @func with @dev as its
 * argument in the workqueue's process context.  @dev will be pinned until
 * @func returns.
 *
490 491 492
 * This routine is usually called via the inline device_schedule_callback(),
 * which automatically sets @owner to THIS_MODULE.
 *
493
 * Returns 0 if the request was submitted, -ENOMEM if storage could not
494
 * be allocated, -ENODEV if a reference to @owner isn't available.
495 496 497 498 499
 *
 * NOTE: This routine won't work if CONFIG_SYSFS isn't set!  It uses an
 * underlying sysfs routine (since it is intended for use by attribute
 * methods), and if sysfs isn't available you'll get nothing but -ENOSYS.
 */
500 501
int device_schedule_callback_owner(struct device *dev,
		void (*func)(struct device *), struct module *owner)
502 503
{
	return sysfs_schedule_callback(&dev->kobj,
504
			(void (*)(void *)) func, dev, owner);
505
}
506
EXPORT_SYMBOL_GPL(device_schedule_callback_owner);
507

508 509 510 511 512 513 514 515 516 517 518 519 520 521
static void klist_children_get(struct klist_node *n)
{
	struct device *dev = container_of(n, struct device, knode_parent);

	get_device(dev);
}

static void klist_children_put(struct klist_node *n)
{
	struct device *dev = container_of(n, struct device, knode_parent);

	put_device(dev);
}

L
Linus Torvalds 已提交
522
/**
523 524
 * device_initialize - init device structure.
 * @dev: device.
L
Linus Torvalds 已提交
525
 *
526 527 528 529 530
 * This prepares the device for use by other layers,
 * including adding it to the device hierarchy.
 * It is the first half of device_register(), if called by
 * that, though it can also be called separately, so one
 * may use @dev's fields (e.g. the refcount).
L
Linus Torvalds 已提交
531 532 533
 */
void device_initialize(struct device *dev)
{
534
	dev->kobj.kset = devices_kset;
535
	kobject_init(&dev->kobj, &device_ktype);
536 537
	klist_init(&dev->klist_children, klist_children_get,
		   klist_children_put);
L
Linus Torvalds 已提交
538
	INIT_LIST_HEAD(&dev->dma_pools);
539
	INIT_LIST_HEAD(&dev->node);
540
	init_MUTEX(&dev->sem);
T
Tejun Heo 已提交
541 542
	spin_lock_init(&dev->devres_lock);
	INIT_LIST_HEAD(&dev->devres_head);
D
David Brownell 已提交
543
	device_init_wakeup(dev, 0);
544
	set_dev_node(dev, -1);
L
Linus Torvalds 已提交
545 546
}

547
#ifdef CONFIG_SYSFS_DEPRECATED
548 549
static struct kobject *get_device_parent(struct device *dev,
					 struct device *parent)
550
{
551
	/* class devices without a parent live in /sys/class/<classname>/ */
552
	if (dev->class && (!parent || parent->class != dev->class))
553
		return &dev->class->p->class_subsys.kobj;
554
	/* all other devices keep their parent */
555
	else if (parent)
556
		return &parent->kobj;
557

558
	return NULL;
559
}
560 561

static inline void cleanup_device_parent(struct device *dev) {}
562 563
static inline void cleanup_glue_dir(struct device *dev,
				    struct kobject *glue_dir) {}
564
#else
565
static struct kobject *virtual_device_parent(struct device *dev)
566
{
567
	static struct kobject *virtual_dir = NULL;
568

569
	if (!virtual_dir)
570
		virtual_dir = kobject_create_and_add("virtual",
571
						     &devices_kset->kobj);
572

573
	return virtual_dir;
574 575
}

576 577
static struct kobject *get_device_parent(struct device *dev,
					 struct device *parent)
578
{
579 580
	int retval;

581 582 583 584 585 586 587
	if (dev->class) {
		struct kobject *kobj = NULL;
		struct kobject *parent_kobj;
		struct kobject *k;

		/*
		 * If we have no parent, we live in "virtual".
588 589
		 * Class-devices with a non class-device as parent, live
		 * in a "glue" directory to prevent namespace collisions.
590 591 592 593 594 595 596 597 598
		 */
		if (parent == NULL)
			parent_kobj = virtual_device_parent(dev);
		else if (parent->class)
			return &parent->kobj;
		else
			parent_kobj = &parent->kobj;

		/* find our class-directory at the parent and reference it */
599 600
		spin_lock(&dev->class->p->class_dirs.list_lock);
		list_for_each_entry(k, &dev->class->p->class_dirs.list, entry)
601 602 603 604
			if (k->parent == parent_kobj) {
				kobj = kobject_get(k);
				break;
			}
605
		spin_unlock(&dev->class->p->class_dirs.list_lock);
606 607 608 609
		if (kobj)
			return kobj;

		/* or create a new class-directory at the parent device */
610 611 612
		k = kobject_create();
		if (!k)
			return NULL;
613
		k->kset = &dev->class->p->class_dirs;
614
		retval = kobject_add(k, parent_kobj, "%s", dev->class->name);
615 616 617 618
		if (retval < 0) {
			kobject_put(k);
			return NULL;
		}
619
		/* do not emit an uevent for this simple "glue" directory */
620
		return k;
621 622 623
	}

	if (parent)
624 625 626
		return &parent->kobj;
	return NULL;
}
627

628
static void cleanup_glue_dir(struct device *dev, struct kobject *glue_dir)
629
{
630
	/* see if we live in a "glue" directory */
631
	if (!glue_dir || !dev->class ||
632
	    glue_dir->kset != &dev->class->p->class_dirs)
633 634
		return;

635
	kobject_put(glue_dir);
636
}
637 638 639 640 641

static void cleanup_device_parent(struct device *dev)
{
	cleanup_glue_dir(dev, dev->kobj.parent);
}
642
#endif
643

644
static void setup_parent(struct device *dev, struct device *parent)
645 646 647 648 649
{
	struct kobject *kobj;
	kobj = get_device_parent(dev, parent);
	if (kobj)
		dev->kobj.parent = kobj;
650 651
}

652 653 654 655 656 657
static int device_add_class_symlinks(struct device *dev)
{
	int error;

	if (!dev->class)
		return 0;
658

659 660
	error = sysfs_create_link(&dev->kobj,
				  &dev->class->p->class_subsys.kobj,
661 662 663
				  "subsystem");
	if (error)
		goto out;
664 665 666

#ifdef CONFIG_SYSFS_DEPRECATED
	/* stacked class devices need a symlink in the class directory */
667
	if (dev->kobj.parent != &dev->class->p->class_subsys.kobj &&
668
	    device_is_not_partition(dev)) {
669
		error = sysfs_create_link(&dev->class->p->class_subsys.kobj,
670
					  &dev->kobj, dev->bus_id);
671 672 673
		if (error)
			goto out_subsys;
	}
674

675
	if (dev->parent && device_is_not_partition(dev)) {
676 677
		struct device *parent = dev->parent;
		char *class_name;
678

679 680 681 682 683 684 685 686 687
		/*
		 * stacked class devices have the 'device' link
		 * pointing to the bus device instead of the parent
		 */
		while (parent->class && !parent->bus && parent->parent)
			parent = parent->parent;

		error = sysfs_create_link(&dev->kobj,
					  &parent->kobj,
688 689 690
					  "device");
		if (error)
			goto out_busid;
691 692 693 694 695 696 697 698 699

		class_name = make_class_name(dev->class->name,
						&dev->kobj);
		if (class_name)
			error = sysfs_create_link(&dev->parent->kobj,
						&dev->kobj, class_name);
		kfree(class_name);
		if (error)
			goto out_device;
700 701 702 703
	}
	return 0;

out_device:
704
	if (dev->parent && device_is_not_partition(dev))
705 706
		sysfs_remove_link(&dev->kobj, "device");
out_busid:
707
	if (dev->kobj.parent != &dev->class->p->class_subsys.kobj &&
708
	    device_is_not_partition(dev))
709 710
		sysfs_remove_link(&dev->class->p->class_subsys.kobj,
				  dev->bus_id);
711 712
#else
	/* link in the class directory pointing to the device */
713 714
	error = sysfs_create_link(&dev->class->p->class_subsys.kobj,
				  &dev->kobj, dev->bus_id);
715 716 717
	if (error)
		goto out_subsys;

718
	if (dev->parent && device_is_not_partition(dev)) {
719 720 721 722 723 724 725 726
		error = sysfs_create_link(&dev->kobj, &dev->parent->kobj,
					  "device");
		if (error)
			goto out_busid;
	}
	return 0;

out_busid:
727
	sysfs_remove_link(&dev->class->p->class_subsys.kobj, dev->bus_id);
728 729
#endif

730 731 732 733 734 735 736 737 738 739
out_subsys:
	sysfs_remove_link(&dev->kobj, "subsystem");
out:
	return error;
}

static void device_remove_class_symlinks(struct device *dev)
{
	if (!dev->class)
		return;
740

741
#ifdef CONFIG_SYSFS_DEPRECATED
742
	if (dev->parent && device_is_not_partition(dev)) {
743 744 745 746 747 748 749 750 751
		char *class_name;

		class_name = make_class_name(dev->class->name, &dev->kobj);
		if (class_name) {
			sysfs_remove_link(&dev->parent->kobj, class_name);
			kfree(class_name);
		}
		sysfs_remove_link(&dev->kobj, "device");
	}
752

753
	if (dev->kobj.parent != &dev->class->p->class_subsys.kobj &&
754
	    device_is_not_partition(dev))
755 756
		sysfs_remove_link(&dev->class->p->class_subsys.kobj,
				  dev->bus_id);
757
#else
758
	if (dev->parent && device_is_not_partition(dev))
759 760
		sysfs_remove_link(&dev->kobj, "device");

761
	sysfs_remove_link(&dev->class->p->class_subsys.kobj, dev->bus_id);
762 763
#endif

764 765 766
	sysfs_remove_link(&dev->kobj, "subsystem");
}

767 768 769
/**
 * dev_set_name - set a device name
 * @dev: device
770
 * @fmt: format string for the device's name
771 772 773 774 775 776 777 778 779 780 781 782
 */
int dev_set_name(struct device *dev, const char *fmt, ...)
{
	va_list vargs;

	va_start(vargs, fmt);
	vsnprintf(dev->bus_id, sizeof(dev->bus_id), fmt, vargs);
	va_end(vargs);
	return 0;
}
EXPORT_SYMBOL_GPL(dev_set_name);

783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830
/**
 * device_to_dev_kobj - select a /sys/dev/ directory for the device
 * @dev: device
 *
 * By default we select char/ for new entries.  Setting class->dev_obj
 * to NULL prevents an entry from being created.  class->dev_kobj must
 * be set (or cleared) before any devices are registered to the class
 * otherwise device_create_sys_dev_entry() and
 * device_remove_sys_dev_entry() will disagree about the the presence
 * of the link.
 */
static struct kobject *device_to_dev_kobj(struct device *dev)
{
	struct kobject *kobj;

	if (dev->class)
		kobj = dev->class->dev_kobj;
	else
		kobj = sysfs_dev_char_kobj;

	return kobj;
}

static int device_create_sys_dev_entry(struct device *dev)
{
	struct kobject *kobj = device_to_dev_kobj(dev);
	int error = 0;
	char devt_str[15];

	if (kobj) {
		format_dev_t(devt_str, dev->devt);
		error = sysfs_create_link(kobj, &dev->kobj, devt_str);
	}

	return error;
}

static void device_remove_sys_dev_entry(struct device *dev)
{
	struct kobject *kobj = device_to_dev_kobj(dev);
	char devt_str[15];

	if (kobj) {
		format_dev_t(devt_str, dev->devt);
		sysfs_remove_link(kobj, devt_str);
	}
}

L
Linus Torvalds 已提交
831
/**
832 833
 * device_add - add device to device hierarchy.
 * @dev: device.
L
Linus Torvalds 已提交
834
 *
835 836
 * This is part 2 of device_register(), though may be called
 * separately _iff_ device_initialize() has been called separately.
L
Linus Torvalds 已提交
837
 *
838 839 840
 * This adds it to the kobject hierarchy via kobject_add(), adds it
 * to the global and sibling lists for the device, then
 * adds it to the other relevant subsystems of the driver model.
L
Linus Torvalds 已提交
841 842 843 844
 */
int device_add(struct device *dev)
{
	struct device *parent = NULL;
845
	struct class_interface *class_intf;
846 847
	int error;

L
Linus Torvalds 已提交
848
	dev = get_device(dev);
849 850
	if (!dev || !strlen(dev->bus_id)) {
		error = -EINVAL;
851
		goto Done;
852
	}
L
Linus Torvalds 已提交
853

854
	pr_debug("device: '%s': %s\n", dev->bus_id, __func__);
855

L
Linus Torvalds 已提交
856
	parent = get_device(dev->parent);
857
	setup_parent(dev, parent);
L
Linus Torvalds 已提交
858

859 860 861 862
	/* use parent numa_node */
	if (parent)
		set_dev_node(dev, dev_to_node(parent));

L
Linus Torvalds 已提交
863
	/* first, register with generic layer. */
864
	error = kobject_add(&dev->kobj, dev->kobj.parent, "%s", dev->bus_id);
865
	if (error)
L
Linus Torvalds 已提交
866
		goto Error;
867

868 869 870 871
	/* notify platform of device entry */
	if (platform_notify)
		platform_notify(dev);

872 873
	/* notify clients of device entry (new way) */
	if (dev->bus)
874
		blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
875 876
					     BUS_NOTIFY_ADD_DEVICE, dev);

877
	error = device_create_file(dev, &uevent_attr);
878 879
	if (error)
		goto attrError;
880

881
	if (MAJOR(dev->devt)) {
882 883
		error = device_create_file(dev, &devt_attr);
		if (error)
884
			goto ueventattrError;
885 886 887 888

		error = device_create_sys_dev_entry(dev);
		if (error)
			goto devtattrError;
889 890
	}

891 892 893
	error = device_add_class_symlinks(dev);
	if (error)
		goto SymlinkError;
894 895
	error = device_add_attrs(dev);
	if (error)
896
		goto AttrsError;
897 898
	error = bus_add_device(dev);
	if (error)
L
Linus Torvalds 已提交
899
		goto BusError;
900 901 902
	error = device_pm_add(dev);
	if (error)
		goto PMError;
903
	kobject_uevent(&dev->kobj, KOBJ_ADD);
904
	bus_attach_device(dev);
L
Linus Torvalds 已提交
905
	if (parent)
906
		klist_add_tail(&dev->knode_parent, &parent->klist_children);
L
Linus Torvalds 已提交
907

908
	if (dev->class) {
909
		mutex_lock(&dev->class->p->class_mutex);
910
		/* tie the class to the device */
911
		list_add_tail(&dev->node, &dev->class->p->class_devices);
912 913

		/* notify any interfaces that the device is here */
914 915
		list_for_each_entry(class_intf,
				    &dev->class->p->class_interfaces, node)
916 917
			if (class_intf->add_dev)
				class_intf->add_dev(dev, class_intf);
918
		mutex_unlock(&dev->class->p->class_mutex);
919
	}
L
Linus Torvalds 已提交
920 921 922 923
 Done:
	put_device(dev);
	return error;
 PMError:
924 925
	bus_remove_device(dev);
 BusError:
926
	if (dev->bus)
927
		blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
928
					     BUS_NOTIFY_DEL_DEVICE, dev);
929
	device_remove_attrs(dev);
930
 AttrsError:
931 932
	device_remove_class_symlinks(dev);
 SymlinkError:
933 934 935
	if (MAJOR(dev->devt))
		device_remove_sys_dev_entry(dev);
 devtattrError:
936 937
	if (MAJOR(dev->devt))
		device_remove_file(dev, &devt_attr);
938
 ueventattrError:
939
	device_remove_file(dev, &uevent_attr);
940
 attrError:
941
	kobject_uevent(&dev->kobj, KOBJ_REMOVE);
L
Linus Torvalds 已提交
942 943
	kobject_del(&dev->kobj);
 Error:
944
	cleanup_device_parent(dev);
L
Linus Torvalds 已提交
945 946 947 948 949 950
	if (parent)
		put_device(parent);
	goto Done;
}

/**
951 952
 * device_register - register a device with the system.
 * @dev: pointer to the device structure
L
Linus Torvalds 已提交
953
 *
954 955 956 957 958 959
 * This happens in two clean steps - initialize the device
 * and add it to the system. The two steps can be called
 * separately, but this is the easiest and most common.
 * I.e. you should only call the two helpers separately if
 * have a clearly defined need to use and refcount the device
 * before it is added to the hierarchy.
L
Linus Torvalds 已提交
960 961 962 963 964 965 966 967
 */
int device_register(struct device *dev)
{
	device_initialize(dev);
	return device_add(dev);
}

/**
968 969
 * get_device - increment reference count for device.
 * @dev: device.
L
Linus Torvalds 已提交
970
 *
971 972 973
 * This simply forwards the call to kobject_get(), though
 * we do take care to provide for the case that we get a NULL
 * pointer passed in.
L
Linus Torvalds 已提交
974
 */
975
struct device *get_device(struct device *dev)
L
Linus Torvalds 已提交
976 977 978 979 980
{
	return dev ? to_dev(kobject_get(&dev->kobj)) : NULL;
}

/**
981 982
 * put_device - decrement reference count.
 * @dev: device in question.
L
Linus Torvalds 已提交
983
 */
984
void put_device(struct device *dev)
L
Linus Torvalds 已提交
985
{
986
	/* might_sleep(); */
L
Linus Torvalds 已提交
987 988 989 990 991
	if (dev)
		kobject_put(&dev->kobj);
}

/**
992 993
 * device_del - delete device from system.
 * @dev: device.
L
Linus Torvalds 已提交
994
 *
995 996 997 998 999
 * This is the first part of the device unregistration
 * sequence. This removes the device from the lists we control
 * from here, has it removed from the other driver model
 * subsystems it was added to in device_add(), and removes it
 * from the kobject hierarchy.
L
Linus Torvalds 已提交
1000
 *
1001 1002
 * NOTE: this should be called manually _iff_ device_add() was
 * also called manually.
L
Linus Torvalds 已提交
1003
 */
1004
void device_del(struct device *dev)
L
Linus Torvalds 已提交
1005
{
1006
	struct device *parent = dev->parent;
1007
	struct class_interface *class_intf;
L
Linus Torvalds 已提交
1008

1009
	device_pm_remove(dev);
L
Linus Torvalds 已提交
1010
	if (parent)
1011
		klist_del(&dev->knode_parent);
1012 1013
	if (MAJOR(dev->devt)) {
		device_remove_sys_dev_entry(dev);
1014
		device_remove_file(dev, &devt_attr);
1015
	}
1016
	if (dev->class) {
1017
		device_remove_class_symlinks(dev);
1018

1019
		mutex_lock(&dev->class->p->class_mutex);
1020
		/* notify any interfaces that the device is now gone */
1021 1022
		list_for_each_entry(class_intf,
				    &dev->class->p->class_interfaces, node)
1023 1024 1025
			if (class_intf->remove_dev)
				class_intf->remove_dev(dev, class_intf);
		/* remove the device from the class list */
1026
		list_del_init(&dev->node);
1027
		mutex_unlock(&dev->class->p->class_mutex);
1028
	}
1029
	device_remove_file(dev, &uevent_attr);
1030
	device_remove_attrs(dev);
1031
	bus_remove_device(dev);
L
Linus Torvalds 已提交
1032

1033 1034 1035 1036 1037 1038 1039
	/*
	 * Some platform devices are driven without driver attached
	 * and managed resources may have been acquired.  Make sure
	 * all resources are released.
	 */
	devres_release_all(dev);

L
Linus Torvalds 已提交
1040 1041 1042 1043 1044
	/* Notify the platform of the removal, in case they
	 * need to do anything...
	 */
	if (platform_notify_remove)
		platform_notify_remove(dev);
1045
	if (dev->bus)
1046
		blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
1047
					     BUS_NOTIFY_DEL_DEVICE, dev);
1048
	kobject_uevent(&dev->kobj, KOBJ_REMOVE);
1049
	cleanup_device_parent(dev);
L
Linus Torvalds 已提交
1050
	kobject_del(&dev->kobj);
1051
	put_device(parent);
L
Linus Torvalds 已提交
1052 1053 1054
}

/**
1055 1056
 * device_unregister - unregister device from system.
 * @dev: device going away.
L
Linus Torvalds 已提交
1057
 *
1058 1059 1060 1061 1062 1063
 * We do this in two parts, like we do device_register(). First,
 * we remove it from all the subsystems with device_del(), then
 * we decrement the reference count via put_device(). If that
 * is the final reference count, the device will be cleaned up
 * via device_release() above. Otherwise, the structure will
 * stick around until the final reference to the device is dropped.
L
Linus Torvalds 已提交
1064
 */
1065
void device_unregister(struct device *dev)
L
Linus Torvalds 已提交
1066
{
1067
	pr_debug("device: '%s': %s\n", dev->bus_id, __func__);
L
Linus Torvalds 已提交
1068 1069 1070 1071
	device_del(dev);
	put_device(dev);
}

1072
static struct device *next_device(struct klist_iter *i)
1073
{
1074
	struct klist_node *n = klist_next(i);
1075 1076 1077
	return n ? container_of(n, struct device, knode_parent) : NULL;
}

L
Linus Torvalds 已提交
1078
/**
1079 1080 1081 1082
 * device_for_each_child - device child iterator.
 * @parent: parent struct device.
 * @data: data for the callback.
 * @fn: function to be called for each device.
L
Linus Torvalds 已提交
1083
 *
1084 1085
 * Iterate over @parent's child devices, and call @fn for each,
 * passing it @data.
L
Linus Torvalds 已提交
1086
 *
1087 1088
 * We check the return of @fn each time. If it returns anything
 * other than 0, we break out and return that value.
L
Linus Torvalds 已提交
1089
 */
1090 1091
int device_for_each_child(struct device *parent, void *data,
			  int (*fn)(struct device *dev, void *data))
L
Linus Torvalds 已提交
1092
{
1093
	struct klist_iter i;
1094
	struct device *child;
L
Linus Torvalds 已提交
1095 1096
	int error = 0;

1097 1098 1099 1100
	klist_iter_init(&parent->klist_children, &i);
	while ((child = next_device(&i)) && !error)
		error = fn(child, data);
	klist_iter_exit(&i);
L
Linus Torvalds 已提交
1101 1102 1103
	return error;
}

1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118
/**
 * device_find_child - device iterator for locating a particular device.
 * @parent: parent struct device
 * @data: Data to pass to match function
 * @match: Callback function to check device
 *
 * This is similar to the device_for_each_child() function above, but it
 * returns a reference to a device that is 'found' for later use, as
 * determined by the @match callback.
 *
 * The callback should return 0 if the device doesn't match and non-zero
 * if it does.  If the callback returns non-zero and a reference to the
 * current device can be obtained, this function will return to the caller
 * and not iterate over any more devices.
 */
1119 1120
struct device *device_find_child(struct device *parent, void *data,
				 int (*match)(struct device *dev, void *data))
1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135
{
	struct klist_iter i;
	struct device *child;

	if (!parent)
		return NULL;

	klist_iter_init(&parent->klist_children, &i);
	while ((child = next_device(&i)))
		if (match(child, data) && get_device(child))
			break;
	klist_iter_exit(&i);
	return child;
}

L
Linus Torvalds 已提交
1136 1137
int __init devices_init(void)
{
1138 1139 1140
	devices_kset = kset_create_and_add("devices", &device_uevent_ops, NULL);
	if (!devices_kset)
		return -ENOMEM;
1141 1142 1143 1144 1145 1146 1147 1148 1149 1150
	dev_kobj = kobject_create_and_add("dev", NULL);
	if (!dev_kobj)
		goto dev_kobj_err;
	sysfs_dev_block_kobj = kobject_create_and_add("block", dev_kobj);
	if (!sysfs_dev_block_kobj)
		goto block_kobj_err;
	sysfs_dev_char_kobj = kobject_create_and_add("char", dev_kobj);
	if (!sysfs_dev_char_kobj)
		goto char_kobj_err;

1151
	return 0;
1152 1153 1154 1155 1156 1157 1158 1159

 char_kobj_err:
	kobject_put(sysfs_dev_block_kobj);
 block_kobj_err:
	kobject_put(dev_kobj);
 dev_kobj_err:
	kset_unregister(devices_kset);
	return -ENOMEM;
L
Linus Torvalds 已提交
1160 1161 1162
}

EXPORT_SYMBOL_GPL(device_for_each_child);
1163
EXPORT_SYMBOL_GPL(device_find_child);
L
Linus Torvalds 已提交
1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175

EXPORT_SYMBOL_GPL(device_initialize);
EXPORT_SYMBOL_GPL(device_add);
EXPORT_SYMBOL_GPL(device_register);

EXPORT_SYMBOL_GPL(device_del);
EXPORT_SYMBOL_GPL(device_unregister);
EXPORT_SYMBOL_GPL(get_device);
EXPORT_SYMBOL_GPL(put_device);

EXPORT_SYMBOL_GPL(device_create_file);
EXPORT_SYMBOL_GPL(device_remove_file);
1176 1177 1178 1179


static void device_create_release(struct device *dev)
{
1180
	pr_debug("device: '%s': %s\n", dev->bus_id, __func__);
1181 1182 1183 1184
	kfree(dev);
}

/**
1185
 * device_create_vargs - creates a device and registers it with sysfs
1186 1187 1188
 * @class: pointer to the struct class that this device should be registered to
 * @parent: pointer to the parent struct device of this new device, if any
 * @devt: the dev_t for the char device to be added
1189
 * @drvdata: the data to be added to the device for callbacks
1190
 * @fmt: string for the device's name
1191
 * @args: va_list for the device's name
1192 1193 1194
 *
 * This function can be used by char device classes.  A struct device
 * will be created in sysfs, registered to the specified class.
1195 1196 1197
 *
 * A "dev" file will be created, showing the dev_t for the device, if
 * the dev_t is not 0,0.
1198 1199 1200 1201
 * If a pointer to a parent struct device is passed in, the newly created
 * struct device will be a child of that device in sysfs.
 * The pointer to the struct device will be returned from the call.
 * Any further sysfs files that might be required can be created using this
1202 1203 1204 1205 1206
 * pointer.
 *
 * Note: the struct class passed to this function must have previously
 * been created with a call to class_create().
 */
1207 1208 1209
struct device *device_create_vargs(struct class *class, struct device *parent,
				   dev_t devt, void *drvdata, const char *fmt,
				   va_list args)
1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226
{
	struct device *dev = NULL;
	int retval = -ENODEV;

	if (class == NULL || IS_ERR(class))
		goto error;

	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
	if (!dev) {
		retval = -ENOMEM;
		goto error;
	}

	dev->devt = devt;
	dev->class = class;
	dev->parent = parent;
	dev->release = device_create_release;
1227
	dev_set_drvdata(dev, drvdata);
1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239

	vsnprintf(dev->bus_id, BUS_ID_SIZE, fmt, args);
	retval = device_register(dev);
	if (retval)
		goto error;

	return dev;

error:
	kfree(dev);
	return ERR_PTR(retval);
}
1240 1241 1242
EXPORT_SYMBOL_GPL(device_create_vargs);

/**
1243
 * device_create - creates a device and registers it with sysfs
1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263
 * @class: pointer to the struct class that this device should be registered to
 * @parent: pointer to the parent struct device of this new device, if any
 * @devt: the dev_t for the char device to be added
 * @drvdata: the data to be added to the device for callbacks
 * @fmt: string for the device's name
 *
 * This function can be used by char device classes.  A struct device
 * will be created in sysfs, registered to the specified class.
 *
 * A "dev" file will be created, showing the dev_t for the device, if
 * the dev_t is not 0,0.
 * If a pointer to a parent struct device is passed in, the newly created
 * struct device will be a child of that device in sysfs.
 * The pointer to the struct device will be returned from the call.
 * Any further sysfs files that might be required can be created using this
 * pointer.
 *
 * Note: the struct class passed to this function must have previously
 * been created with a call to class_create().
 */
1264 1265
struct device *device_create(struct class *class, struct device *parent,
			     dev_t devt, void *drvdata, const char *fmt, ...)
1266 1267 1268 1269 1270 1271 1272 1273 1274
{
	va_list vargs;
	struct device *dev;

	va_start(vargs, fmt);
	dev = device_create_vargs(class, parent, devt, drvdata, fmt, vargs);
	va_end(vargs);
	return dev;
}
1275
EXPORT_SYMBOL_GPL(device_create);
1276

1277
static int __match_devt(struct device *dev, void *data)
1278
{
1279
	dev_t *devt = data;
1280

1281
	return dev->devt == *devt;
1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294
}

/**
 * device_destroy - removes a device that was created with device_create()
 * @class: pointer to the struct class that this device was registered with
 * @devt: the dev_t of the device that was previously registered
 *
 * This call unregisters and cleans up a device that was created with a
 * call to device_create().
 */
void device_destroy(struct class *class, dev_t devt)
{
	struct device *dev;
1295

1296
	dev = class_find_device(class, NULL, &devt, __match_devt);
1297 1298
	if (dev) {
		put_device(dev);
1299
		device_unregister(dev);
1300
	}
1301 1302
}
EXPORT_SYMBOL_GPL(device_destroy);
1303 1304 1305 1306 1307 1308 1309 1310 1311 1312

/**
 * device_rename - renames a device
 * @dev: the pointer to the struct device to be renamed
 * @new_name: the new name of the device
 */
int device_rename(struct device *dev, char *new_name)
{
	char *old_class_name = NULL;
	char *new_class_name = NULL;
1313
	char *old_device_name = NULL;
1314 1315 1316 1317 1318 1319
	int error;

	dev = get_device(dev);
	if (!dev)
		return -EINVAL;

1320
	pr_debug("device: '%s': %s: renaming to '%s'\n", dev->bus_id,
1321
		 __func__, new_name);
1322

1323
#ifdef CONFIG_SYSFS_DEPRECATED
1324 1325
	if ((dev->class) && (dev->parent))
		old_class_name = make_class_name(dev->class->name, &dev->kobj);
1326
#endif
1327

1328 1329 1330 1331
	old_device_name = kmalloc(BUS_ID_SIZE, GFP_KERNEL);
	if (!old_device_name) {
		error = -ENOMEM;
		goto out;
1332
	}
1333
	strlcpy(old_device_name, dev->bus_id, BUS_ID_SIZE);
1334 1335 1336
	strlcpy(dev->bus_id, new_name, BUS_ID_SIZE);

	error = kobject_rename(&dev->kobj, new_name);
1337 1338 1339 1340
	if (error) {
		strlcpy(dev->bus_id, old_device_name, BUS_ID_SIZE);
		goto out;
	}
1341

1342
#ifdef CONFIG_SYSFS_DEPRECATED
1343 1344 1345
	if (old_class_name) {
		new_class_name = make_class_name(dev->class->name, &dev->kobj);
		if (new_class_name) {
1346 1347 1348
			error = sysfs_create_link_nowarn(&dev->parent->kobj,
							 &dev->kobj,
							 new_class_name);
1349 1350
			if (error)
				goto out;
1351 1352 1353
			sysfs_remove_link(&dev->parent->kobj, old_class_name);
		}
	}
1354
#else
1355
	if (dev->class) {
1356 1357
		error = sysfs_create_link_nowarn(&dev->class->p->class_subsys.kobj,
						 &dev->kobj, dev->bus_id);
1358 1359
		if (error)
			goto out;
1360
		sysfs_remove_link(&dev->class->p->class_subsys.kobj,
1361
				  old_device_name);
1362
	}
1363 1364
#endif

1365
out:
1366 1367 1368
	put_device(dev);

	kfree(new_class_name);
1369
	kfree(old_class_name);
1370
	kfree(old_device_name);
1371 1372 1373

	return error;
}
1374
EXPORT_SYMBOL_GPL(device_rename);
1375 1376 1377 1378 1379

static int device_move_class_links(struct device *dev,
				   struct device *old_parent,
				   struct device *new_parent)
{
1380
	int error = 0;
1381 1382 1383 1384 1385
#ifdef CONFIG_SYSFS_DEPRECATED
	char *class_name;

	class_name = make_class_name(dev->class->name, &dev->kobj);
	if (!class_name) {
1386
		error = -ENOMEM;
1387 1388 1389 1390 1391 1392
		goto out;
	}
	if (old_parent) {
		sysfs_remove_link(&dev->kobj, "device");
		sysfs_remove_link(&old_parent->kobj, class_name);
	}
1393 1394 1395 1396 1397 1398 1399 1400 1401
	if (new_parent) {
		error = sysfs_create_link(&dev->kobj, &new_parent->kobj,
					  "device");
		if (error)
			goto out;
		error = sysfs_create_link(&new_parent->kobj, &dev->kobj,
					  class_name);
		if (error)
			sysfs_remove_link(&dev->kobj, "device");
1402
	} else
1403
		error = 0;
1404 1405 1406 1407
out:
	kfree(class_name);
	return error;
#else
1408 1409 1410 1411 1412 1413
	if (old_parent)
		sysfs_remove_link(&dev->kobj, "device");
	if (new_parent)
		error = sysfs_create_link(&dev->kobj, &new_parent->kobj,
					  "device");
	return error;
1414 1415 1416 1417 1418 1419
#endif
}

/**
 * device_move - moves a device to a new parent
 * @dev: the pointer to the struct device to be moved
1420
 * @new_parent: the new parent of the device (can by NULL)
1421 1422 1423 1424 1425
 */
int device_move(struct device *dev, struct device *new_parent)
{
	int error;
	struct device *old_parent;
1426
	struct kobject *new_parent_kobj;
1427 1428 1429 1430 1431 1432

	dev = get_device(dev);
	if (!dev)
		return -EINVAL;

	new_parent = get_device(new_parent);
1433
	new_parent_kobj = get_device_parent(dev, new_parent);
1434

1435
	pr_debug("device: '%s': %s: moving to '%s'\n", dev->bus_id,
1436
		 __func__, new_parent ? new_parent->bus_id : "<NULL>");
1437
	error = kobject_move(&dev->kobj, new_parent_kobj);
1438
	if (error) {
1439
		cleanup_glue_dir(dev, new_parent_kobj);
1440 1441 1442 1443 1444 1445
		put_device(new_parent);
		goto out;
	}
	old_parent = dev->parent;
	dev->parent = new_parent;
	if (old_parent)
1446
		klist_remove(&dev->knode_parent);
1447
	if (new_parent) {
1448
		klist_add_tail(&dev->knode_parent, &new_parent->klist_children);
1449 1450 1451
		set_dev_node(dev, dev_to_node(new_parent));
	}

1452 1453 1454 1455 1456 1457 1458
	if (!dev->class)
		goto out_put;
	error = device_move_class_links(dev, old_parent, new_parent);
	if (error) {
		/* We ignore errors on cleanup since we're hosed anyway... */
		device_move_class_links(dev, new_parent, old_parent);
		if (!kobject_move(&dev->kobj, &old_parent->kobj)) {
1459 1460
			if (new_parent)
				klist_remove(&dev->knode_parent);
1461 1462
			dev->parent = old_parent;
			if (old_parent) {
1463 1464
				klist_add_tail(&dev->knode_parent,
					       &old_parent->klist_children);
1465 1466
				set_dev_node(dev, dev_to_node(old_parent));
			}
1467
		}
1468
		cleanup_glue_dir(dev, new_parent_kobj);
1469 1470 1471 1472 1473 1474 1475 1476 1477 1478
		put_device(new_parent);
		goto out;
	}
out_put:
	put_device(old_parent);
out:
	put_device(dev);
	return error;
}
EXPORT_SYMBOL_GPL(device_move);
1479 1480 1481 1482 1483 1484

/**
 * device_shutdown - call ->shutdown() on each device to shutdown.
 */
void device_shutdown(void)
{
1485
	struct device *dev, *devn;
1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496

	list_for_each_entry_safe_reverse(dev, devn, &devices_kset->list,
				kobj.entry) {
		if (dev->bus && dev->bus->shutdown) {
			dev_dbg(dev, "shutdown\n");
			dev->bus->shutdown(dev);
		} else if (dev->driver && dev->driver->shutdown) {
			dev_dbg(dev, "shutdown\n");
			dev->driver->shutdown(dev);
		}
	}
1497 1498 1499
	kobject_put(sysfs_dev_char_kobj);
	kobject_put(sysfs_dev_block_kobj);
	kobject_put(dev_kobj);
1500
}