projects/linux·blob v3.13 · 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/kobj_completion.h>
17#include <linux/string.h>
18#include <linux/export.h>
19#include <linux/stat.h>
20#include <linux/slab.h>
21
22/**
23 * kobject_namespace - return @kobj's namespace tag
24 * @kobj: kobject in question
25 *
26 * Returns namespace tag of @kobj if its parent has namespace ops enabled
27 * and thus @kobj should have a namespace tag associated with it. Returns
28 * %NULL otherwise.
29 */
30const void *kobject_namespace(struct kobject *kobj)
31{
32 const struct kobj_ns_type_operations *ns_ops = kobj_ns_ops(kobj);
33
34 if (!ns_ops || ns_ops->type == KOBJ_NS_TYPE_NONE)
35 return NULL;
36
37 return kobj->ktype->namespace(kobj);
38}
39
40/*
41 * populate_dir - populate directory with attributes.
42 * @kobj: object we're working on.
43 *
44 * Most subsystems have a set of default attributes that are associated
45 * with an object that registers with them. This is a helper called during
46 * object registration that loops through the default attributes of the
47 * subsystem and creates attributes files for them in sysfs.
48 */
49static int populate_dir(struct kobject *kobj)
50{
51 struct kobj_type *t = get_ktype(kobj);
52 struct attribute *attr;
53 int error = 0;
54 int i;
55
56 if (t && t->default_attrs) {
57 for (i = 0; (attr = t->default_attrs[i]) != NULL; i++) {
58 error = sysfs_create_file(kobj, attr);
59 if (error)
60 break;
61 }
62 }
63 return error;
64}
65
66static int create_dir(struct kobject *kobj)
67{
68 int error;
69
70 error = sysfs_create_dir_ns(kobj, kobject_namespace(kobj));
71 if (!error) {
72 error = populate_dir(kobj);
73 if (error)
74 sysfs_remove_dir(kobj);
75 }
76
77 /*
78 * @kobj->sd may be deleted by an ancestor going away. Hold an
79 * extra reference so that it stays until @kobj is gone.
80 */
81 sysfs_get(kobj->sd);
82
83 return error;
84}
85
86static int get_kobj_path_length(struct kobject *kobj)
87{
88 int length = 1;
89 struct kobject *parent = kobj;
90
91 /* walk up the ancestors until we hit the one pointing to the
92 * root.
93 * Add 1 to strlen for leading '/' of each level.
94 */
95 do {
96 if (kobject_name(parent) == NULL)
97 return 0;
98 length += strlen(kobject_name(parent)) + 1;
99 parent = parent->parent;
100 } while (parent);
101 return length;
102}
103
104static void fill_kobj_path(struct kobject *kobj, char *path, int length)
105{
106 struct kobject *parent;
107
108 --length;
109 for (parent = kobj; parent; parent = parent->parent) {
110 int cur = strlen(kobject_name(parent));
111 /* back up enough to print this name with '/' */
112 length -= cur;
113 strncpy(path + length, kobject_name(parent), cur);
114 *(path + --length) = '/';
115 }
116
117 pr_debug("kobject: '%s' (%p): %s: path = '%s'\n", kobject_name(kobj),
118 kobj, __func__, path);
119}
120
121/**
122 * kobject_get_path - generate and return the path associated with a given kobj and kset pair.
123 *
124 * @kobj: kobject in question, with which to build the path
125 * @gfp_mask: the allocation type used to allocate the path
126 *
127 * The result must be freed by the caller with kfree().
128 */
129char *kobject_get_path(struct kobject *kobj, gfp_t gfp_mask)
130{
131 char *path;
132 int len;
133
134 len = get_kobj_path_length(kobj);
135 if (len == 0)
136 return NULL;
137 path = kzalloc(len, gfp_mask);
138 if (!path)
139 return NULL;
140 fill_kobj_path(kobj, path, len);
141
142 return path;
143}
144EXPORT_SYMBOL_GPL(kobject_get_path);
145
146/* add the kobject to its kset's list */
147static void kobj_kset_join(struct kobject *kobj)
148{
149 if (!kobj->kset)
150 return;
151
152 kset_get(kobj->kset);
153 spin_lock(&kobj->kset->list_lock);
154 list_add_tail(&kobj->entry, &kobj->kset->list);
155 spin_unlock(&kobj->kset->list_lock);
156}
157
158/* remove the kobject from its kset's list */
159static void kobj_kset_leave(struct kobject *kobj)
160{
161 if (!kobj->kset)
162 return;
163
164 spin_lock(&kobj->kset->list_lock);
165 list_del_init(&kobj->entry);
166 spin_unlock(&kobj->kset->list_lock);
167 kset_put(kobj->kset);
168}
169
170static void kobject_init_internal(struct kobject *kobj)
171{
172 if (!kobj)
173 return;
174 kref_init(&kobj->kref);
175 INIT_LIST_HEAD(&kobj->entry);
176 kobj->state_in_sysfs = 0;
177 kobj->state_add_uevent_sent = 0;
178 kobj->state_remove_uevent_sent = 0;
179 kobj->state_initialized = 1;
180}
181
182
183static int kobject_add_internal(struct kobject *kobj)
184{
185 int error = 0;
186 struct kobject *parent;
187
188 if (!kobj)
189 return -ENOENT;
190
191 if (!kobj->name || !kobj->name[0]) {
192 WARN(1, "kobject: (%p): attempted to be registered with empty "
193 "name!\n", kobj);
194 return -EINVAL;
195 }
196
197 parent = kobject_get(kobj->parent);
198
199 /* join kset if set, use it as parent if we do not already have one */
200 if (kobj->kset) {
201 if (!parent)
202 parent = kobject_get(&kobj->kset->kobj);
203 kobj_kset_join(kobj);
204 kobj->parent = parent;
205 }
206
207 pr_debug("kobject: '%s' (%p): %s: parent: '%s', set: '%s'\n",
208 kobject_name(kobj), kobj, __func__,
209 parent ? kobject_name(parent) : "<NULL>",
210 kobj->kset ? kobject_name(&kobj->kset->kobj) : "<NULL>");
211
212 error = create_dir(kobj);
213 if (error) {
214 kobj_kset_leave(kobj);
215 kobject_put(parent);
216 kobj->parent = NULL;
217
218 /* be noisy on error issues */
219 if (error == -EEXIST)
220 WARN(1, "%s failed for %s with "
221 "-EEXIST, don't try to register things with "
222 "the same name in the same directory.\n",
223 __func__, kobject_name(kobj));
224 else
225 WARN(1, "%s failed for %s (error: %d parent: %s)\n",
226 __func__, kobject_name(kobj), error,
227 parent ? kobject_name(parent) : "'none'");
228 } else
229 kobj->state_in_sysfs = 1;
230
231 return error;
232}
233
234/**
235 * kobject_set_name_vargs - Set the name of an kobject
236 * @kobj: struct kobject to set the name of
237 * @fmt: format string used to build the name
238 * @vargs: vargs to format the string.
239 */
240int kobject_set_name_vargs(struct kobject *kobj, const char *fmt,
241 va_list vargs)
242{
243 const char *old_name = kobj->name;
244 char *s;
245
246 if (kobj->name && !fmt)
247 return 0;
248
249 kobj->name = kvasprintf(GFP_KERNEL, fmt, vargs);
250 if (!kobj->name)
251 return -ENOMEM;
252
253 /* ewww... some of these buggers have '/' in the name ... */
254 while ((s = strchr(kobj->name, '/')))
255 s[0] = '!';
256
257 kfree(old_name);
258 return 0;
259}
260
261/**
262 * kobject_set_name - Set the name of a kobject
263 * @kobj: struct kobject to set the name of
264 * @fmt: format string used to build the name
265 *
266 * This sets the name of the kobject. If you have already added the
267 * kobject to the system, you must call kobject_rename() in order to
268 * change the name of the kobject.
269 */
270int kobject_set_name(struct kobject *kobj, const char *fmt, ...)
271{
272 va_list vargs;
273 int retval;
274
275 va_start(vargs, fmt);
276 retval = kobject_set_name_vargs(kobj, fmt, vargs);
277 va_end(vargs);
278
279 return retval;
280}
281EXPORT_SYMBOL(kobject_set_name);
282
283/**
284 * kobject_init - initialize a kobject structure
285 * @kobj: pointer to the kobject to initialize
286 * @ktype: pointer to the ktype for this kobject.
287 *
288 * This function will properly initialize a kobject such that it can then
289 * be passed to the kobject_add() call.
290 *
291 * After this function is called, the kobject MUST be cleaned up by a call
292 * to kobject_put(), not by a call to kfree directly to ensure that all of
293 * the memory is cleaned up properly.
294 */
295void kobject_init(struct kobject *kobj, struct kobj_type *ktype)
296{
297 char *err_str;
298
299 if (!kobj) {
300 err_str = "invalid kobject pointer!";
301 goto error;
302 }
303 if (!ktype) {
304 err_str = "must have a ktype to be initialized properly!\n";
305 goto error;
306 }
307 if (kobj->state_initialized) {
308 /* do not error out as sometimes we can recover */
309 printk(KERN_ERR "kobject (%p): tried to init an initialized "
310 "object, something is seriously wrong.\n", kobj);
311 dump_stack();
312 }
313
314 kobject_init_internal(kobj);
315 kobj->ktype = ktype;
316 return;
317
318error:
319 printk(KERN_ERR "kobject (%p): %s\n", kobj, err_str);
320 dump_stack();
321}
322EXPORT_SYMBOL(kobject_init);
323
324static int kobject_add_varg(struct kobject *kobj, struct kobject *parent,
325 const char *fmt, va_list vargs)
326{
327 int retval;
328
329 retval = kobject_set_name_vargs(kobj, fmt, vargs);
330 if (retval) {
331 printk(KERN_ERR "kobject: can not set name properly!\n");
332 return retval;
333 }
334 kobj->parent = parent;
335 return kobject_add_internal(kobj);
336}
337
338/**
339 * kobject_add - the main kobject add function
340 * @kobj: the kobject to add
341 * @parent: pointer to the parent of the kobject.
342 * @fmt: format to name the kobject with.
343 *
344 * The kobject name is set and added to the kobject hierarchy in this
345 * function.
346 *
347 * If @parent is set, then the parent of the @kobj will be set to it.
348 * If @parent is NULL, then the parent of the @kobj will be set to the
349 * kobject associted with the kset assigned to this kobject. If no kset
350 * is assigned to the kobject, then the kobject will be located in the
351 * root of the sysfs tree.
352 *
353 * If this function returns an error, kobject_put() must be called to
354 * properly clean up the memory associated with the object.
355 * Under no instance should the kobject that is passed to this function
356 * be directly freed with a call to kfree(), that can leak memory.
357 *
358 * Note, no "add" uevent will be created with this call, the caller should set
359 * up all of the necessary sysfs files for the object and then call
360 * kobject_uevent() with the UEVENT_ADD parameter to ensure that
361 * userspace is properly notified of this kobject's creation.
362 */
363int kobject_add(struct kobject *kobj, struct kobject *parent,
364 const char *fmt, ...)
365{
366 va_list args;
367 int retval;
368
369 if (!kobj)
370 return -EINVAL;
371
372 if (!kobj->state_initialized) {
373 printk(KERN_ERR "kobject '%s' (%p): tried to add an "
374 "uninitialized object, something is seriously wrong.\n",
375 kobject_name(kobj), kobj);
376 dump_stack();
377 return -EINVAL;
378 }
379 va_start(args, fmt);
380 retval = kobject_add_varg(kobj, parent, fmt, args);
381 va_end(args);
382
383 return retval;
384}
385EXPORT_SYMBOL(kobject_add);
386
387/**
388 * kobject_init_and_add - initialize a kobject structure and add it to the kobject hierarchy
389 * @kobj: pointer to the kobject to initialize
390 * @ktype: pointer to the ktype for this kobject.
391 * @parent: pointer to the parent of this kobject.
392 * @fmt: the name of the kobject.
393 *
394 * This function combines the call to kobject_init() and
395 * kobject_add(). The same type of error handling after a call to
396 * kobject_add() and kobject lifetime rules are the same here.
397 */
398int kobject_init_and_add(struct kobject *kobj, struct kobj_type *ktype,
399 struct kobject *parent, const char *fmt, ...)
400{
401 va_list args;
402 int retval;
403
404 kobject_init(kobj, ktype);
405
406 va_start(args, fmt);
407 retval = kobject_add_varg(kobj, parent, fmt, args);
408 va_end(args);
409
410 return retval;
411}
412EXPORT_SYMBOL_GPL(kobject_init_and_add);
413
414/**
415 * kobject_rename - change the name of an object
416 * @kobj: object in question.
417 * @new_name: object's new name
418 *
419 * It is the responsibility of the caller to provide mutual
420 * exclusion between two different calls of kobject_rename
421 * on the same kobject and to ensure that new_name is valid and
422 * won't conflict with other kobjects.
423 */
424int kobject_rename(struct kobject *kobj, const char *new_name)
425{
426 int error = 0;
427 const char *devpath = NULL;
428 const char *dup_name = NULL, *name;
429 char *devpath_string = NULL;
430 char *envp[2];
431
432 kobj = kobject_get(kobj);
433 if (!kobj)
434 return -EINVAL;
435 if (!kobj->parent)
436 return -EINVAL;
437
438 devpath = kobject_get_path(kobj, GFP_KERNEL);
439 if (!devpath) {
440 error = -ENOMEM;
441 goto out;
442 }
443 devpath_string = kmalloc(strlen(devpath) + 15, GFP_KERNEL);
444 if (!devpath_string) {
445 error = -ENOMEM;
446 goto out;
447 }
448 sprintf(devpath_string, "DEVPATH_OLD=%s", devpath);
449 envp[0] = devpath_string;
450 envp[1] = NULL;
451
452 name = dup_name = kstrdup(new_name, GFP_KERNEL);
453 if (!name) {
454 error = -ENOMEM;
455 goto out;
456 }
457
458 error = sysfs_rename_dir_ns(kobj, new_name, kobject_namespace(kobj));
459 if (error)
460 goto out;
461
462 /* Install the new kobject name */
463 dup_name = kobj->name;
464 kobj->name = name;
465
466 /* This function is mostly/only used for network interface.
467 * Some hotplug package track interfaces by their name and
468 * therefore want to know when the name is changed by the user. */
469 kobject_uevent_env(kobj, KOBJ_MOVE, envp);
470
471out:
472 kfree(dup_name);
473 kfree(devpath_string);
474 kfree(devpath);
475 kobject_put(kobj);
476
477 return error;
478}
479EXPORT_SYMBOL_GPL(kobject_rename);
480
481/**
482 * kobject_move - move object to another parent
483 * @kobj: object in question.
484 * @new_parent: object's new parent (can be NULL)
485 */
486int kobject_move(struct kobject *kobj, struct kobject *new_parent)
487{
488 int error;
489 struct kobject *old_parent;
490 const char *devpath = NULL;
491 char *devpath_string = NULL;
492 char *envp[2];
493
494 kobj = kobject_get(kobj);
495 if (!kobj)
496 return -EINVAL;
497 new_parent = kobject_get(new_parent);
498 if (!new_parent) {
499 if (kobj->kset)
500 new_parent = kobject_get(&kobj->kset->kobj);
501 }
502
503 /* old object path */
504 devpath = kobject_get_path(kobj, GFP_KERNEL);
505 if (!devpath) {
506 error = -ENOMEM;
507 goto out;
508 }
509 devpath_string = kmalloc(strlen(devpath) + 15, GFP_KERNEL);
510 if (!devpath_string) {
511 error = -ENOMEM;
512 goto out;
513 }
514 sprintf(devpath_string, "DEVPATH_OLD=%s", devpath);
515 envp[0] = devpath_string;
516 envp[1] = NULL;
517 error = sysfs_move_dir_ns(kobj, new_parent, kobject_namespace(kobj));
518 if (error)
519 goto out;
520 old_parent = kobj->parent;
521 kobj->parent = new_parent;
522 new_parent = NULL;
523 kobject_put(old_parent);
524 kobject_uevent_env(kobj, KOBJ_MOVE, envp);
525out:
526 kobject_put(new_parent);
527 kobject_put(kobj);
528 kfree(devpath_string);
529 kfree(devpath);
530 return error;
531}
532
533/**
534 * kobject_del - unlink kobject from hierarchy.
535 * @kobj: object.
536 */
537void kobject_del(struct kobject *kobj)
538{
539 struct sysfs_dirent *sd;
540
541 if (!kobj)
542 return;
543
544 sd = kobj->sd;
545 sysfs_remove_dir(kobj);
546 sysfs_put(sd);
547
548 kobj->state_in_sysfs = 0;
549 kobj_kset_leave(kobj);
550 kobject_put(kobj->parent);
551 kobj->parent = NULL;
552}
553
554/**
555 * kobject_get - increment refcount for object.
556 * @kobj: object.
557 */
558struct kobject *kobject_get(struct kobject *kobj)
559{
560 if (kobj)
561 kref_get(&kobj->kref);
562 return kobj;
563}
564
565static struct kobject * __must_check kobject_get_unless_zero(struct kobject *kobj)
566{
567 if (!kref_get_unless_zero(&kobj->kref))
568 kobj = NULL;
569 return kobj;
570}
571
572/*
573 * kobject_cleanup - free kobject resources.
574 * @kobj: object to cleanup
575 */
576static void kobject_cleanup(struct kobject *kobj)
577{
578 struct kobj_type *t = get_ktype(kobj);
579 const char *name = kobj->name;
580
581 pr_debug("kobject: '%s' (%p): %s, parent %p\n",
582 kobject_name(kobj), kobj, __func__, kobj->parent);
583
584 if (t && !t->release)
585 pr_debug("kobject: '%s' (%p): does not have a release() "
586 "function, it is broken and must be fixed.\n",
587 kobject_name(kobj), kobj);
588
589 /* send "remove" if the caller did not do it but sent "add" */
590 if (kobj->state_add_uevent_sent && !kobj->state_remove_uevent_sent) {
591 pr_debug("kobject: '%s' (%p): auto cleanup 'remove' event\n",
592 kobject_name(kobj), kobj);
593 kobject_uevent(kobj, KOBJ_REMOVE);
594 }
595
596 /* remove from sysfs if the caller did not do it */
597 if (kobj->state_in_sysfs) {
598 pr_debug("kobject: '%s' (%p): auto cleanup kobject_del\n",
599 kobject_name(kobj), kobj);
600 kobject_del(kobj);
601 }
602
603 if (t && t->release) {
604 pr_debug("kobject: '%s' (%p): calling ktype release\n",
605 kobject_name(kobj), kobj);
606 t->release(kobj);
607 }
608
609 /* free name if we allocated it */
610 if (name) {
611 pr_debug("kobject: '%s': free name\n", name);
612 kfree(name);
613 }
614}
615
616#ifdef CONFIG_DEBUG_KOBJECT_RELEASE
617static void kobject_delayed_cleanup(struct work_struct *work)
618{
619 kobject_cleanup(container_of(to_delayed_work(work),
620 struct kobject, release));
621}
622#endif
623
624static void kobject_release(struct kref *kref)
625{
626 struct kobject *kobj = container_of(kref, struct kobject, kref);
627#ifdef CONFIG_DEBUG_KOBJECT_RELEASE
628 pr_info("kobject: '%s' (%p): %s, parent %p (delayed)\n",
629 kobject_name(kobj), kobj, __func__, kobj->parent);
630 INIT_DELAYED_WORK(&kobj->release, kobject_delayed_cleanup);
631 schedule_delayed_work(&kobj->release, HZ);
632#else
633 kobject_cleanup(kobj);
634#endif
635}
636
637/**
638 * kobject_put - decrement refcount for object.
639 * @kobj: object.
640 *
641 * Decrement the refcount, and if 0, call kobject_cleanup().
642 */
643void kobject_put(struct kobject *kobj)
644{
645 if (kobj) {
646 if (!kobj->state_initialized)
647 WARN(1, KERN_WARNING "kobject: '%s' (%p): is not "
648 "initialized, yet kobject_put() is being "
649 "called.\n", kobject_name(kobj), kobj);
650 kref_put(&kobj->kref, kobject_release);
651 }
652}
653
654static void dynamic_kobj_release(struct kobject *kobj)
655{
656 pr_debug("kobject: (%p): %s\n", kobj, __func__);
657 kfree(kobj);
658}
659
660static struct kobj_type dynamic_kobj_ktype = {
661 .release = dynamic_kobj_release,
662 .sysfs_ops = &kobj_sysfs_ops,
663};
664
665/**
666 * kobject_create - create a struct kobject dynamically
667 *
668 * This function creates a kobject structure dynamically and sets it up
669 * to be a "dynamic" kobject with a default release function set up.
670 *
671 * If the kobject was not able to be created, NULL will be returned.
672 * The kobject structure returned from here must be cleaned up with a
673 * call to kobject_put() and not kfree(), as kobject_init() has
674 * already been called on this structure.
675 */
676struct kobject *kobject_create(void)
677{
678 struct kobject *kobj;
679
680 kobj = kzalloc(sizeof(*kobj), GFP_KERNEL);
681 if (!kobj)
682 return NULL;
683
684 kobject_init(kobj, &dynamic_kobj_ktype);
685 return kobj;
686}
687
688/**
689 * kobject_create_and_add - create a struct kobject dynamically and register it with sysfs
690 *
691 * @name: the name for the kobject
692 * @parent: the parent kobject of this kobject, if any.
693 *
694 * This function creates a kobject structure dynamically and registers it
695 * with sysfs. When you are finished with this structure, call
696 * kobject_put() and the structure will be dynamically freed when
697 * it is no longer being used.
698 *
699 * If the kobject was not able to be created, NULL will be returned.
700 */
701struct kobject *kobject_create_and_add(const char *name, struct kobject *parent)
702{
703 struct kobject *kobj;
704 int retval;
705
706 kobj = kobject_create();
707 if (!kobj)
708 return NULL;
709
710 retval = kobject_add(kobj, parent, "%s", name);
711 if (retval) {
712 printk(KERN_WARNING "%s: kobject_add error: %d\n",
713 __func__, retval);
714 kobject_put(kobj);
715 kobj = NULL;
716 }
717 return kobj;
718}
719EXPORT_SYMBOL_GPL(kobject_create_and_add);
720
721/**
722 * kset_init - initialize a kset for use
723 * @k: kset
724 */
725void kset_init(struct kset *k)
726{
727 kobject_init_internal(&k->kobj);
728 INIT_LIST_HEAD(&k->list);
729 spin_lock_init(&k->list_lock);
730}
731
732/* default kobject attribute operations */
733static ssize_t kobj_attr_show(struct kobject *kobj, struct attribute *attr,
734 char *buf)
735{
736 struct kobj_attribute *kattr;
737 ssize_t ret = -EIO;
738
739 kattr = container_of(attr, struct kobj_attribute, attr);
740 if (kattr->show)
741 ret = kattr->show(kobj, kattr, buf);
742 return ret;
743}
744
745static ssize_t kobj_attr_store(struct kobject *kobj, struct attribute *attr,
746 const char *buf, size_t count)
747{
748 struct kobj_attribute *kattr;
749 ssize_t ret = -EIO;
750
751 kattr = container_of(attr, struct kobj_attribute, attr);
752 if (kattr->store)
753 ret = kattr->store(kobj, kattr, buf, count);
754 return ret;
755}
756
757const struct sysfs_ops kobj_sysfs_ops = {
758 .show = kobj_attr_show,
759 .store = kobj_attr_store,
760};
761
762/**
763 * kobj_completion_init - initialize a kobj_completion object.
764 * @kc: kobj_completion
765 * @ktype: type of kobject to initialize
766 *
767 * kobj_completion structures can be embedded within structures with different
768 * lifetime rules. During the release of the enclosing object, we can
769 * wait on the release of the kobject so that we don't free it while it's
770 * still busy.
771 */
772void kobj_completion_init(struct kobj_completion *kc, struct kobj_type *ktype)
773{
774 init_completion(&kc->kc_unregister);
775 kobject_init(&kc->kc_kobj, ktype);
776}
777EXPORT_SYMBOL_GPL(kobj_completion_init);
778
779/**
780 * kobj_completion_release - release a kobj_completion object
781 * @kobj: kobject embedded in kobj_completion
782 *
783 * Used with kobject_release to notify waiters that the kobject has been
784 * released.
785 */
786void kobj_completion_release(struct kobject *kobj)
787{
788 struct kobj_completion *kc = kobj_to_kobj_completion(kobj);
789 complete(&kc->kc_unregister);
790}
791EXPORT_SYMBOL_GPL(kobj_completion_release);
792
793/**
794 * kobj_completion_del_and_wait - release the kobject and wait for it
795 * @kc: kobj_completion object to release
796 *
797 * Delete the kobject from sysfs and drop the reference count. Then wait
798 * until any other outstanding references are also dropped. This routine
799 * is only necessary once other references may have been taken on the
800 * kobject. Typically this happens when the kobject has been published
801 * to sysfs via kobject_add.
802 */
803void kobj_completion_del_and_wait(struct kobj_completion *kc)
804{
805 kobject_del(&kc->kc_kobj);
806 kobject_put(&kc->kc_kobj);
807 wait_for_completion(&kc->kc_unregister);
808}
809EXPORT_SYMBOL_GPL(kobj_completion_del_and_wait);
810
811/**
812 * kset_register - initialize and add a kset.
813 * @k: kset.
814 */
815int kset_register(struct kset *k)
816{
817 int err;
818
819 if (!k)
820 return -EINVAL;
821
822 kset_init(k);
823 err = kobject_add_internal(&k->kobj);
824 if (err)
825 return err;
826 kobject_uevent(&k->kobj, KOBJ_ADD);
827 return 0;
828}
829
830/**
831 * kset_unregister - remove a kset.
832 * @k: kset.
833 */
834void kset_unregister(struct kset *k)
835{
836 if (!k)
837 return;
838 kobject_put(&k->kobj);
839}
840
841/**
842 * kset_find_obj - search for object in kset.
843 * @kset: kset we're looking in.
844 * @name: object's name.
845 *
846 * Lock kset via @kset->subsys, and iterate over @kset->list,
847 * looking for a matching kobject. If matching object is found
848 * take a reference and return the object.
849 */
850struct kobject *kset_find_obj(struct kset *kset, const char *name)
851{
852 struct kobject *k;
853 struct kobject *ret = NULL;
854
855 spin_lock(&kset->list_lock);
856
857 list_for_each_entry(k, &kset->list, entry) {
858 if (kobject_name(k) && !strcmp(kobject_name(k), name)) {
859 ret = kobject_get_unless_zero(k);
860 break;
861 }
862 }
863
864 spin_unlock(&kset->list_lock);
865 return ret;
866}
867
868static void kset_release(struct kobject *kobj)
869{
870 struct kset *kset = container_of(kobj, struct kset, kobj);
871 pr_debug("kobject: '%s' (%p): %s\n",
872 kobject_name(kobj), kobj, __func__);
873 kfree(kset);
874}
875
876static struct kobj_type kset_ktype = {
877 .sysfs_ops = &kobj_sysfs_ops,
878 .release = kset_release,
879};
880
881/**
882 * kset_create - create a struct kset dynamically
883 *
884 * @name: the name for the kset
885 * @uevent_ops: a struct kset_uevent_ops for the kset
886 * @parent_kobj: the parent kobject of this kset, if any.
887 *
888 * This function creates a kset structure dynamically. This structure can
889 * then be registered with the system and show up in sysfs with a call to
890 * kset_register(). When you are finished with this structure, if
891 * kset_register() has been called, call kset_unregister() and the
892 * structure will be dynamically freed when it is no longer being used.
893 *
894 * If the kset was not able to be created, NULL will be returned.
895 */
896static struct kset *kset_create(const char *name,
897 const struct kset_uevent_ops *uevent_ops,
898 struct kobject *parent_kobj)
899{
900 struct kset *kset;
901 int retval;
902
903 kset = kzalloc(sizeof(*kset), GFP_KERNEL);
904 if (!kset)
905 return NULL;
906 retval = kobject_set_name(&kset->kobj, "%s", name);
907 if (retval) {
908 kfree(kset);
909 return NULL;
910 }
911 kset->uevent_ops = uevent_ops;
912 kset->kobj.parent = parent_kobj;
913
914 /*
915 * The kobject of this kset will have a type of kset_ktype and belong to
916 * no kset itself. That way we can properly free it when it is
917 * finished being used.
918 */
919 kset->kobj.ktype = &kset_ktype;
920 kset->kobj.kset = NULL;
921
922 return kset;
923}
924
925/**
926 * kset_create_and_add - create a struct kset dynamically and add it to sysfs
927 *
928 * @name: the name for the kset
929 * @uevent_ops: a struct kset_uevent_ops for the kset
930 * @parent_kobj: the parent kobject of this kset, if any.
931 *
932 * This function creates a kset structure dynamically and registers it
933 * with sysfs. When you are finished with this structure, call
934 * kset_unregister() and the structure will be dynamically freed when it
935 * is no longer being used.
936 *
937 * If the kset was not able to be created, NULL will be returned.
938 */
939struct kset *kset_create_and_add(const char *name,
940 const struct kset_uevent_ops *uevent_ops,
941 struct kobject *parent_kobj)
942{
943 struct kset *kset;
944 int error;
945
946 kset = kset_create(name, uevent_ops, parent_kobj);
947 if (!kset)
948 return NULL;
949 error = kset_register(kset);
950 if (error) {
951 kfree(kset);
952 return NULL;
953 }
954 return kset;
955}
956EXPORT_SYMBOL_GPL(kset_create_and_add);
957
958
959static DEFINE_SPINLOCK(kobj_ns_type_lock);
960static const struct kobj_ns_type_operations *kobj_ns_ops_tbl[KOBJ_NS_TYPES];
961
962int kobj_ns_type_register(const struct kobj_ns_type_operations *ops)
963{
964 enum kobj_ns_type type = ops->type;
965 int error;
966
967 spin_lock(&kobj_ns_type_lock);
968
969 error = -EINVAL;
970 if (type >= KOBJ_NS_TYPES)
971 goto out;
972
973 error = -EINVAL;
974 if (type <= KOBJ_NS_TYPE_NONE)
975 goto out;
976
977 error = -EBUSY;
978 if (kobj_ns_ops_tbl[type])
979 goto out;
980
981 error = 0;
982 kobj_ns_ops_tbl[type] = ops;
983
984out:
985 spin_unlock(&kobj_ns_type_lock);
986 return error;
987}
988
989int kobj_ns_type_registered(enum kobj_ns_type type)
990{
991 int registered = 0;
992
993 spin_lock(&kobj_ns_type_lock);
994 if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES))
995 registered = kobj_ns_ops_tbl[type] != NULL;
996 spin_unlock(&kobj_ns_type_lock);
997
998 return registered;
999}
1000
1001const struct kobj_ns_type_operations *kobj_child_ns_ops(struct kobject *parent)
1002{
1003 const struct kobj_ns_type_operations *ops = NULL;
1004
1005 if (parent && parent->ktype->child_ns_type)
1006 ops = parent->ktype->child_ns_type(parent);
1007
1008 return ops;
1009}
1010
1011const struct kobj_ns_type_operations *kobj_ns_ops(struct kobject *kobj)
1012{
1013 return kobj_child_ns_ops(kobj->parent);
1014}
1015
1016bool kobj_ns_current_may_mount(enum kobj_ns_type type)
1017{
1018 bool may_mount = true;
1019
1020 spin_lock(&kobj_ns_type_lock);
1021 if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
1022 kobj_ns_ops_tbl[type])
1023 may_mount = kobj_ns_ops_tbl[type]->current_may_mount();
1024 spin_unlock(&kobj_ns_type_lock);
1025
1026 return may_mount;
1027}
1028
1029void *kobj_ns_grab_current(enum kobj_ns_type type)
1030{
1031 void *ns = NULL;
1032
1033 spin_lock(&kobj_ns_type_lock);
1034 if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
1035 kobj_ns_ops_tbl[type])
1036 ns = kobj_ns_ops_tbl[type]->grab_current_ns();
1037 spin_unlock(&kobj_ns_type_lock);
1038
1039 return ns;
1040}
1041
1042const void *kobj_ns_netlink(enum kobj_ns_type type, struct sock *sk)
1043{
1044 const void *ns = NULL;
1045
1046 spin_lock(&kobj_ns_type_lock);
1047 if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
1048 kobj_ns_ops_tbl[type])
1049 ns = kobj_ns_ops_tbl[type]->netlink_ns(sk);
1050 spin_unlock(&kobj_ns_type_lock);
1051
1052 return ns;
1053}
1054
1055const void *kobj_ns_initial(enum kobj_ns_type type)
1056{
1057 const void *ns = NULL;
1058
1059 spin_lock(&kobj_ns_type_lock);
1060 if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
1061 kobj_ns_ops_tbl[type])
1062 ns = kobj_ns_ops_tbl[type]->initial_ns();
1063 spin_unlock(&kobj_ns_type_lock);
1064
1065 return ns;
1066}
1067
1068void kobj_ns_drop(enum kobj_ns_type type, void *ns)
1069{
1070 spin_lock(&kobj_ns_type_lock);
1071 if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
1072 kobj_ns_ops_tbl[type] && kobj_ns_ops_tbl[type]->drop_ns)
1073 kobj_ns_ops_tbl[type]->drop_ns(ns);
1074 spin_unlock(&kobj_ns_type_lock);
1075}
1076
1077EXPORT_SYMBOL(kobject_get);
1078EXPORT_SYMBOL(kobject_put);
1079EXPORT_SYMBOL(kobject_del);
1080
1081EXPORT_SYMBOL(kset_register);
1082EXPORT_SYMBOL(kset_unregister);