projects/linux·blob v2.6.26-rc2 · refs

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1/*
2 * kobject.c - library routines for handling generic kernel objects
3 *
4 * Copyright (c) 2002-2003 Patrick Mochel <[email protected]>
5 * Copyright (c) 2006-2007 Greg Kroah-Hartman <[email protected]>
6 * Copyright (c) 2006-2007 Novell Inc.
7 *
8 * This file is released under the GPLv2.
9 *
10 *
11 * Please see the file Documentation/kobject.txt for critical information
12 * about using the kobject interface.
13 */
14
15#include <linux/kobject.h>
16#include <linux/string.h>
17#include <linux/module.h>
18#include <linux/stat.h>
19#include <linux/slab.h>
20
21/*
22 * populate_dir - populate directory with attributes.
23 * @kobj: object we're working on.
24 *
25 * Most subsystems have a set of default attributes that are associated
26 * with an object that registers with them. This is a helper called during
27 * object registration that loops through the default attributes of the
28 * subsystem and creates attributes files for them in sysfs.
29 */
30static int populate_dir(struct kobject *kobj)
31{
32 struct kobj_type *t = get_ktype(kobj);
33 struct attribute *attr;
34 int error = 0;
35 int i;
36
37 if (t && t->default_attrs) {
38 for (i = 0; (attr = t->default_attrs[i]) != NULL; i++) {
39 error = sysfs_create_file(kobj, attr);
40 if (error)
41 break;
42 }
43 }
44 return error;
45}
46
47static int create_dir(struct kobject *kobj)
48{
49 int error = 0;
50 if (kobject_name(kobj)) {
51 error = sysfs_create_dir(kobj);
52 if (!error) {
53 error = populate_dir(kobj);
54 if (error)
55 sysfs_remove_dir(kobj);
56 }
57 }
58 return error;
59}
60
61static int get_kobj_path_length(struct kobject *kobj)
62{
63 int length = 1;
64 struct kobject *parent = kobj;
65
66 /* walk up the ancestors until we hit the one pointing to the
67 * root.
68 * Add 1 to strlen for leading '/' of each level.
69 */
70 do {
71 if (kobject_name(parent) == NULL)
72 return 0;
73 length += strlen(kobject_name(parent)) + 1;
74 parent = parent->parent;
75 } while (parent);
76 return length;
77}
78
79static void fill_kobj_path(struct kobject *kobj, char *path, int length)
80{
81 struct kobject *parent;
82
83 --length;
84 for (parent = kobj; parent; parent = parent->parent) {
85 int cur = strlen(kobject_name(parent));
86 /* back up enough to print this name with '/' */
87 length -= cur;
88 strncpy(path + length, kobject_name(parent), cur);
89 *(path + --length) = '/';
90 }
91
92 pr_debug("kobject: '%s' (%p): %s: path = '%s'\n", kobject_name(kobj),
93 kobj, __func__, path);
94}
95
96/**
97 * kobject_get_path - generate and return the path associated with a given kobj and kset pair.
98 *
99 * @kobj: kobject in question, with which to build the path
100 * @gfp_mask: the allocation type used to allocate the path
101 *
102 * The result must be freed by the caller with kfree().
103 */
104char *kobject_get_path(struct kobject *kobj, gfp_t gfp_mask)
105{
106 char *path;
107 int len;
108
109 len = get_kobj_path_length(kobj);
110 if (len == 0)
111 return NULL;
112 path = kzalloc(len, gfp_mask);
113 if (!path)
114 return NULL;
115 fill_kobj_path(kobj, path, len);
116
117 return path;
118}
119EXPORT_SYMBOL_GPL(kobject_get_path);
120
121/* add the kobject to its kset's list */
122static void kobj_kset_join(struct kobject *kobj)
123{
124 if (!kobj->kset)
125 return;
126
127 kset_get(kobj->kset);
128 spin_lock(&kobj->kset->list_lock);
129 list_add_tail(&kobj->entry, &kobj->kset->list);
130 spin_unlock(&kobj->kset->list_lock);
131}
132
133/* remove the kobject from its kset's list */
134static void kobj_kset_leave(struct kobject *kobj)
135{
136 if (!kobj->kset)
137 return;
138
139 spin_lock(&kobj->kset->list_lock);
140 list_del_init(&kobj->entry);
141 spin_unlock(&kobj->kset->list_lock);
142 kset_put(kobj->kset);
143}
144
145static void kobject_init_internal(struct kobject *kobj)
146{
147 if (!kobj)
148 return;
149 kref_init(&kobj->kref);
150 INIT_LIST_HEAD(&kobj->entry);
151 kobj->state_in_sysfs = 0;
152 kobj->state_add_uevent_sent = 0;
153 kobj->state_remove_uevent_sent = 0;
154 kobj->state_initialized = 1;
155}
156
157
158static int kobject_add_internal(struct kobject *kobj)
159{
160 int error = 0;
161 struct kobject *parent;
162
163 if (!kobj)
164 return -ENOENT;
165
166 if (!kobj->name || !kobj->name[0]) {
167 pr_debug("kobject: (%p): attempted to be registered with empty "
168 "name!\n", kobj);
169 WARN_ON(1);
170 return -EINVAL;
171 }
172
173 parent = kobject_get(kobj->parent);
174
175 /* join kset if set, use it as parent if we do not already have one */
176 if (kobj->kset) {
177 if (!parent)
178 parent = kobject_get(&kobj->kset->kobj);
179 kobj_kset_join(kobj);
180 kobj->parent = parent;
181 }
182
183 pr_debug("kobject: '%s' (%p): %s: parent: '%s', set: '%s'\n",
184 kobject_name(kobj), kobj, __func__,
185 parent ? kobject_name(parent) : "<NULL>",
186 kobj->kset ? kobject_name(&kobj->kset->kobj) : "<NULL>");
187
188 error = create_dir(kobj);
189 if (error) {
190 kobj_kset_leave(kobj);
191 kobject_put(parent);
192 kobj->parent = NULL;
193
194 /* be noisy on error issues */
195 if (error == -EEXIST)
196 printk(KERN_ERR "%s failed for %s with "
197 "-EEXIST, don't try to register things with "
198 "the same name in the same directory.\n",
199 __func__, kobject_name(kobj));
200 else
201 printk(KERN_ERR "%s failed for %s (%d)\n",
202 __func__, kobject_name(kobj), error);
203 dump_stack();
204 } else
205 kobj->state_in_sysfs = 1;
206
207 return error;
208}
209
210/**
211 * kobject_set_name_vargs - Set the name of an kobject
212 * @kobj: struct kobject to set the name of
213 * @fmt: format string used to build the name
214 * @vargs: vargs to format the string.
215 */
216static int kobject_set_name_vargs(struct kobject *kobj, const char *fmt,
217 va_list vargs)
218{
219 /* Free the old name, if necessary. */
220 kfree(kobj->name);
221
222 kobj->name = kvasprintf(GFP_KERNEL, fmt, vargs);
223 if (!kobj->name)
224 return -ENOMEM;
225
226 return 0;
227}
228
229/**
230 * kobject_set_name - Set the name of a kobject
231 * @kobj: struct kobject to set the name of
232 * @fmt: format string used to build the name
233 *
234 * This sets the name of the kobject. If you have already added the
235 * kobject to the system, you must call kobject_rename() in order to
236 * change the name of the kobject.
237 */
238int kobject_set_name(struct kobject *kobj, const char *fmt, ...)
239{
240 va_list vargs;
241 int retval;
242
243 va_start(vargs, fmt);
244 retval = kobject_set_name_vargs(kobj, fmt, vargs);
245 va_end(vargs);
246
247 return retval;
248}
249EXPORT_SYMBOL(kobject_set_name);
250
251/**
252 * kobject_init - initialize a kobject structure
253 * @kobj: pointer to the kobject to initialize
254 * @ktype: pointer to the ktype for this kobject.
255 *
256 * This function will properly initialize a kobject such that it can then
257 * be passed to the kobject_add() call.
258 *
259 * After this function is called, the kobject MUST be cleaned up by a call
260 * to kobject_put(), not by a call to kfree directly to ensure that all of
261 * the memory is cleaned up properly.
262 */
263void kobject_init(struct kobject *kobj, struct kobj_type *ktype)
264{
265 char *err_str;
266
267 if (!kobj) {
268 err_str = "invalid kobject pointer!";
269 goto error;
270 }
271 if (!ktype) {
272 err_str = "must have a ktype to be initialized properly!\n";
273 goto error;
274 }
275 if (kobj->state_initialized) {
276 /* do not error out as sometimes we can recover */
277 printk(KERN_ERR "kobject (%p): tried to init an initialized "
278 "object, something is seriously wrong.\n", kobj);
279 dump_stack();
280 }
281
282 kobject_init_internal(kobj);
283 kobj->ktype = ktype;
284 return;
285
286error:
287 printk(KERN_ERR "kobject (%p): %s\n", kobj, err_str);
288 dump_stack();
289}
290EXPORT_SYMBOL(kobject_init);
291
292static int kobject_add_varg(struct kobject *kobj, struct kobject *parent,
293 const char *fmt, va_list vargs)
294{
295 int retval;
296
297 retval = kobject_set_name_vargs(kobj, fmt, vargs);
298 if (retval) {
299 printk(KERN_ERR "kobject: can not set name properly!\n");
300 return retval;
301 }
302 kobj->parent = parent;
303 return kobject_add_internal(kobj);
304}
305
306/**
307 * kobject_add - the main kobject add function
308 * @kobj: the kobject to add
309 * @parent: pointer to the parent of the kobject.
310 * @fmt: format to name the kobject with.
311 *
312 * The kobject name is set and added to the kobject hierarchy in this
313 * function.
314 *
315 * If @parent is set, then the parent of the @kobj will be set to it.
316 * If @parent is NULL, then the parent of the @kobj will be set to the
317 * kobject associted with the kset assigned to this kobject. If no kset
318 * is assigned to the kobject, then the kobject will be located in the
319 * root of the sysfs tree.
320 *
321 * If this function returns an error, kobject_put() must be called to
322 * properly clean up the memory associated with the object.
323 * Under no instance should the kobject that is passed to this function
324 * be directly freed with a call to kfree(), that can leak memory.
325 *
326 * Note, no "add" uevent will be created with this call, the caller should set
327 * up all of the necessary sysfs files for the object and then call
328 * kobject_uevent() with the UEVENT_ADD parameter to ensure that
329 * userspace is properly notified of this kobject's creation.
330 */
331int kobject_add(struct kobject *kobj, struct kobject *parent,
332 const char *fmt, ...)
333{
334 va_list args;
335 int retval;
336
337 if (!kobj)
338 return -EINVAL;
339
340 if (!kobj->state_initialized) {
341 printk(KERN_ERR "kobject '%s' (%p): tried to add an "
342 "uninitialized object, something is seriously wrong.\n",
343 kobject_name(kobj), kobj);
344 dump_stack();
345 return -EINVAL;
346 }
347 va_start(args, fmt);
348 retval = kobject_add_varg(kobj, parent, fmt, args);
349 va_end(args);
350
351 return retval;
352}
353EXPORT_SYMBOL(kobject_add);
354
355/**
356 * kobject_init_and_add - initialize a kobject structure and add it to the kobject hierarchy
357 * @kobj: pointer to the kobject to initialize
358 * @ktype: pointer to the ktype for this kobject.
359 * @parent: pointer to the parent of this kobject.
360 * @fmt: the name of the kobject.
361 *
362 * This function combines the call to kobject_init() and
363 * kobject_add(). The same type of error handling after a call to
364 * kobject_add() and kobject lifetime rules are the same here.
365 */
366int kobject_init_and_add(struct kobject *kobj, struct kobj_type *ktype,
367 struct kobject *parent, const char *fmt, ...)
368{
369 va_list args;
370 int retval;
371
372 kobject_init(kobj, ktype);
373
374 va_start(args, fmt);
375 retval = kobject_add_varg(kobj, parent, fmt, args);
376 va_end(args);
377
378 return retval;
379}
380EXPORT_SYMBOL_GPL(kobject_init_and_add);
381
382/**
383 * kobject_rename - change the name of an object
384 * @kobj: object in question.
385 * @new_name: object's new name
386 */
387int kobject_rename(struct kobject *kobj, const char *new_name)
388{
389 int error = 0;
390 const char *devpath = NULL;
391 char *devpath_string = NULL;
392 char *envp[2];
393
394 kobj = kobject_get(kobj);
395 if (!kobj)
396 return -EINVAL;
397 if (!kobj->parent)
398 return -EINVAL;
399
400 /* see if this name is already in use */
401 if (kobj->kset) {
402 struct kobject *temp_kobj;
403 temp_kobj = kset_find_obj(kobj->kset, new_name);
404 if (temp_kobj) {
405 printk(KERN_WARNING "kobject '%s' cannot be renamed "
406 "to '%s' as '%s' is already in existence.\n",
407 kobject_name(kobj), new_name, new_name);
408 kobject_put(temp_kobj);
409 return -EINVAL;
410 }
411 }
412
413 devpath = kobject_get_path(kobj, GFP_KERNEL);
414 if (!devpath) {
415 error = -ENOMEM;
416 goto out;
417 }
418 devpath_string = kmalloc(strlen(devpath) + 15, GFP_KERNEL);
419 if (!devpath_string) {
420 error = -ENOMEM;
421 goto out;
422 }
423 sprintf(devpath_string, "DEVPATH_OLD=%s", devpath);
424 envp[0] = devpath_string;
425 envp[1] = NULL;
426
427 error = sysfs_rename_dir(kobj, new_name);
428
429 /* This function is mostly/only used for network interface.
430 * Some hotplug package track interfaces by their name and
431 * therefore want to know when the name is changed by the user. */
432 if (!error)
433 kobject_uevent_env(kobj, KOBJ_MOVE, envp);
434
435out:
436 kfree(devpath_string);
437 kfree(devpath);
438 kobject_put(kobj);
439
440 return error;
441}
442
443/**
444 * kobject_move - move object to another parent
445 * @kobj: object in question.
446 * @new_parent: object's new parent (can be NULL)
447 */
448int kobject_move(struct kobject *kobj, struct kobject *new_parent)
449{
450 int error;
451 struct kobject *old_parent;
452 const char *devpath = NULL;
453 char *devpath_string = NULL;
454 char *envp[2];
455
456 kobj = kobject_get(kobj);
457 if (!kobj)
458 return -EINVAL;
459 new_parent = kobject_get(new_parent);
460 if (!new_parent) {
461 if (kobj->kset)
462 new_parent = kobject_get(&kobj->kset->kobj);
463 }
464 /* old object path */
465 devpath = kobject_get_path(kobj, GFP_KERNEL);
466 if (!devpath) {
467 error = -ENOMEM;
468 goto out;
469 }
470 devpath_string = kmalloc(strlen(devpath) + 15, GFP_KERNEL);
471 if (!devpath_string) {
472 error = -ENOMEM;
473 goto out;
474 }
475 sprintf(devpath_string, "DEVPATH_OLD=%s", devpath);
476 envp[0] = devpath_string;
477 envp[1] = NULL;
478 error = sysfs_move_dir(kobj, new_parent);
479 if (error)
480 goto out;
481 old_parent = kobj->parent;
482 kobj->parent = new_parent;
483 new_parent = NULL;
484 kobject_put(old_parent);
485 kobject_uevent_env(kobj, KOBJ_MOVE, envp);
486out:
487 kobject_put(new_parent);
488 kobject_put(kobj);
489 kfree(devpath_string);
490 kfree(devpath);
491 return error;
492}
493
494/**
495 * kobject_del - unlink kobject from hierarchy.
496 * @kobj: object.
497 */
498void kobject_del(struct kobject *kobj)
499{
500 if (!kobj)
501 return;
502
503 sysfs_remove_dir(kobj);
504 kobj->state_in_sysfs = 0;
505 kobj_kset_leave(kobj);
506 kobject_put(kobj->parent);
507 kobj->parent = NULL;
508}
509
510/**
511 * kobject_get - increment refcount for object.
512 * @kobj: object.
513 */
514struct kobject *kobject_get(struct kobject *kobj)
515{
516 if (kobj)
517 kref_get(&kobj->kref);
518 return kobj;
519}
520
521/*
522 * kobject_cleanup - free kobject resources.
523 * @kobj: object to cleanup
524 */
525static void kobject_cleanup(struct kobject *kobj)
526{
527 struct kobj_type *t = get_ktype(kobj);
528 const char *name = kobj->name;
529
530 pr_debug("kobject: '%s' (%p): %s\n",
531 kobject_name(kobj), kobj, __func__);
532
533 if (t && !t->release)
534 pr_debug("kobject: '%s' (%p): does not have a release() "
535 "function, it is broken and must be fixed.\n",
536 kobject_name(kobj), kobj);
537
538 /* send "remove" if the caller did not do it but sent "add" */
539 if (kobj->state_add_uevent_sent && !kobj->state_remove_uevent_sent) {
540 pr_debug("kobject: '%s' (%p): auto cleanup 'remove' event\n",
541 kobject_name(kobj), kobj);
542 kobject_uevent(kobj, KOBJ_REMOVE);
543 }
544
545 /* remove from sysfs if the caller did not do it */
546 if (kobj->state_in_sysfs) {
547 pr_debug("kobject: '%s' (%p): auto cleanup kobject_del\n",
548 kobject_name(kobj), kobj);
549 kobject_del(kobj);
550 }
551
552 if (t && t->release) {
553 pr_debug("kobject: '%s' (%p): calling ktype release\n",
554 kobject_name(kobj), kobj);
555 t->release(kobj);
556 }
557
558 /* free name if we allocated it */
559 if (name) {
560 pr_debug("kobject: '%s': free name\n", name);
561 kfree(name);
562 }
563}
564
565static void kobject_release(struct kref *kref)
566{
567 kobject_cleanup(container_of(kref, struct kobject, kref));
568}
569
570/**
571 * kobject_put - decrement refcount for object.
572 * @kobj: object.
573 *
574 * Decrement the refcount, and if 0, call kobject_cleanup().
575 */
576void kobject_put(struct kobject *kobj)
577{
578 if (kobj) {
579 if (!kobj->state_initialized) {
580 printk(KERN_WARNING "kobject: '%s' (%p): is not "
581 "initialized, yet kobject_put() is being "
582 "called.\n", kobject_name(kobj), kobj);
583 WARN_ON(1);
584 }
585 kref_put(&kobj->kref, kobject_release);
586 }
587}
588
589static void dynamic_kobj_release(struct kobject *kobj)
590{
591 pr_debug("kobject: (%p): %s\n", kobj, __func__);
592 kfree(kobj);
593}
594
595static struct kobj_type dynamic_kobj_ktype = {
596 .release = dynamic_kobj_release,
597 .sysfs_ops = &kobj_sysfs_ops,
598};
599
600/**
601 * kobject_create - create a struct kobject dynamically
602 *
603 * This function creates a kobject structure dynamically and sets it up
604 * to be a "dynamic" kobject with a default release function set up.
605 *
606 * If the kobject was not able to be created, NULL will be returned.
607 * The kobject structure returned from here must be cleaned up with a
608 * call to kobject_put() and not kfree(), as kobject_init() has
609 * already been called on this structure.
610 */
611struct kobject *kobject_create(void)
612{
613 struct kobject *kobj;
614
615 kobj = kzalloc(sizeof(*kobj), GFP_KERNEL);
616 if (!kobj)
617 return NULL;
618
619 kobject_init(kobj, &dynamic_kobj_ktype);
620 return kobj;
621}
622
623/**
624 * kobject_create_and_add - create a struct kobject dynamically and register it with sysfs
625 *
626 * @name: the name for the kset
627 * @parent: the parent kobject of this kobject, if any.
628 *
629 * This function creates a kobject structure dynamically and registers it
630 * with sysfs. When you are finished with this structure, call
631 * kobject_put() and the structure will be dynamically freed when
632 * it is no longer being used.
633 *
634 * If the kobject was not able to be created, NULL will be returned.
635 */
636struct kobject *kobject_create_and_add(const char *name, struct kobject *parent)
637{
638 struct kobject *kobj;
639 int retval;
640
641 kobj = kobject_create();
642 if (!kobj)
643 return NULL;
644
645 retval = kobject_add(kobj, parent, "%s", name);
646 if (retval) {
647 printk(KERN_WARNING "%s: kobject_add error: %d\n",
648 __func__, retval);
649 kobject_put(kobj);
650 kobj = NULL;
651 }
652 return kobj;
653}
654EXPORT_SYMBOL_GPL(kobject_create_and_add);
655
656/**
657 * kset_init - initialize a kset for use
658 * @k: kset
659 */
660void kset_init(struct kset *k)
661{
662 kobject_init_internal(&k->kobj);
663 INIT_LIST_HEAD(&k->list);
664 spin_lock_init(&k->list_lock);
665}
666
667/* default kobject attribute operations */
668static ssize_t kobj_attr_show(struct kobject *kobj, struct attribute *attr,
669 char *buf)
670{
671 struct kobj_attribute *kattr;
672 ssize_t ret = -EIO;
673
674 kattr = container_of(attr, struct kobj_attribute, attr);
675 if (kattr->show)
676 ret = kattr->show(kobj, kattr, buf);
677 return ret;
678}
679
680static ssize_t kobj_attr_store(struct kobject *kobj, struct attribute *attr,
681 const char *buf, size_t count)
682{
683 struct kobj_attribute *kattr;
684 ssize_t ret = -EIO;
685
686 kattr = container_of(attr, struct kobj_attribute, attr);
687 if (kattr->store)
688 ret = kattr->store(kobj, kattr, buf, count);
689 return ret;
690}
691
692struct sysfs_ops kobj_sysfs_ops = {
693 .show = kobj_attr_show,
694 .store = kobj_attr_store,
695};
696
697/**
698 * kset_register - initialize and add a kset.
699 * @k: kset.
700 */
701int kset_register(struct kset *k)
702{
703 int err;
704
705 if (!k)
706 return -EINVAL;
707
708 kset_init(k);
709 err = kobject_add_internal(&k->kobj);
710 if (err)
711 return err;
712 kobject_uevent(&k->kobj, KOBJ_ADD);
713 return 0;
714}
715
716/**
717 * kset_unregister - remove a kset.
718 * @k: kset.
719 */
720void kset_unregister(struct kset *k)
721{
722 if (!k)
723 return;
724 kobject_put(&k->kobj);
725}
726
727/**
728 * kset_find_obj - search for object in kset.
729 * @kset: kset we're looking in.
730 * @name: object's name.
731 *
732 * Lock kset via @kset->subsys, and iterate over @kset->list,
733 * looking for a matching kobject. If matching object is found
734 * take a reference and return the object.
735 */
736struct kobject *kset_find_obj(struct kset *kset, const char *name)
737{
738 struct kobject *k;
739 struct kobject *ret = NULL;
740
741 spin_lock(&kset->list_lock);
742 list_for_each_entry(k, &kset->list, entry) {
743 if (kobject_name(k) && !strcmp(kobject_name(k), name)) {
744 ret = kobject_get(k);
745 break;
746 }
747 }
748 spin_unlock(&kset->list_lock);
749 return ret;
750}
751
752static void kset_release(struct kobject *kobj)
753{
754 struct kset *kset = container_of(kobj, struct kset, kobj);
755 pr_debug("kobject: '%s' (%p): %s\n",
756 kobject_name(kobj), kobj, __func__);
757 kfree(kset);
758}
759
760static struct kobj_type kset_ktype = {
761 .sysfs_ops = &kobj_sysfs_ops,
762 .release = kset_release,
763};
764
765/**
766 * kset_create - create a struct kset dynamically
767 *
768 * @name: the name for the kset
769 * @uevent_ops: a struct kset_uevent_ops for the kset
770 * @parent_kobj: the parent kobject of this kset, if any.
771 *
772 * This function creates a kset structure dynamically. This structure can
773 * then be registered with the system and show up in sysfs with a call to
774 * kset_register(). When you are finished with this structure, if
775 * kset_register() has been called, call kset_unregister() and the
776 * structure will be dynamically freed when it is no longer being used.
777 *
778 * If the kset was not able to be created, NULL will be returned.
779 */
780static struct kset *kset_create(const char *name,
781 struct kset_uevent_ops *uevent_ops,
782 struct kobject *parent_kobj)
783{
784 struct kset *kset;
785
786 kset = kzalloc(sizeof(*kset), GFP_KERNEL);
787 if (!kset)
788 return NULL;
789 kobject_set_name(&kset->kobj, name);
790 kset->uevent_ops = uevent_ops;
791 kset->kobj.parent = parent_kobj;
792
793 /*
794 * The kobject of this kset will have a type of kset_ktype and belong to
795 * no kset itself. That way we can properly free it when it is
796 * finished being used.
797 */
798 kset->kobj.ktype = &kset_ktype;
799 kset->kobj.kset = NULL;
800
801 return kset;
802}
803
804/**
805 * kset_create_and_add - create a struct kset dynamically and add it to sysfs
806 *
807 * @name: the name for the kset
808 * @uevent_ops: a struct kset_uevent_ops for the kset
809 * @parent_kobj: the parent kobject of this kset, if any.
810 *
811 * This function creates a kset structure dynamically and registers it
812 * with sysfs. When you are finished with this structure, call
813 * kset_unregister() and the structure will be dynamically freed when it
814 * is no longer being used.
815 *
816 * If the kset was not able to be created, NULL will be returned.
817 */
818struct kset *kset_create_and_add(const char *name,
819 struct kset_uevent_ops *uevent_ops,
820 struct kobject *parent_kobj)
821{
822 struct kset *kset;
823 int error;
824
825 kset = kset_create(name, uevent_ops, parent_kobj);
826 if (!kset)
827 return NULL;
828 error = kset_register(kset);
829 if (error) {
830 kfree(kset);
831 return NULL;
832 }
833 return kset;
834}
835EXPORT_SYMBOL_GPL(kset_create_and_add);
836
837EXPORT_SYMBOL(kobject_get);
838EXPORT_SYMBOL(kobject_put);
839EXPORT_SYMBOL(kobject_del);
840
841EXPORT_SYMBOL(kset_register);
842EXPORT_SYMBOL(kset_unregister);