projects/linux·blob v3.18-rc3 · 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/export.h>
18#include <linux/stat.h>
19#include <linux/slab.h>
20#include <linux/random.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 const struct kobj_ns_type_operations *ops;
69 int error;
70
71 error = sysfs_create_dir_ns(kobj, kobject_namespace(kobj));
72 if (error)
73 return error;
74
75 error = populate_dir(kobj);
76 if (error) {
77 sysfs_remove_dir(kobj);
78 return error;
79 }
80
81 /*
82 * @kobj->sd may be deleted by an ancestor going away. Hold an
83 * extra reference so that it stays until @kobj is gone.
84 */
85 sysfs_get(kobj->sd);
86
87 /*
88 * If @kobj has ns_ops, its children need to be filtered based on
89 * their namespace tags. Enable namespace support on @kobj->sd.
90 */
91 ops = kobj_child_ns_ops(kobj);
92 if (ops) {
93 BUG_ON(ops->type <= KOBJ_NS_TYPE_NONE);
94 BUG_ON(ops->type >= KOBJ_NS_TYPES);
95 BUG_ON(!kobj_ns_type_registered(ops->type));
96
97 sysfs_enable_ns(kobj->sd);
98 }
99
100 return 0;
101}
102
103static int get_kobj_path_length(struct kobject *kobj)
104{
105 int length = 1;
106 struct kobject *parent = kobj;
107
108 /* walk up the ancestors until we hit the one pointing to the
109 * root.
110 * Add 1 to strlen for leading '/' of each level.
111 */
112 do {
113 if (kobject_name(parent) == NULL)
114 return 0;
115 length += strlen(kobject_name(parent)) + 1;
116 parent = parent->parent;
117 } while (parent);
118 return length;
119}
120
121static void fill_kobj_path(struct kobject *kobj, char *path, int length)
122{
123 struct kobject *parent;
124
125 --length;
126 for (parent = kobj; parent; parent = parent->parent) {
127 int cur = strlen(kobject_name(parent));
128 /* back up enough to print this name with '/' */
129 length -= cur;
130 strncpy(path + length, kobject_name(parent), cur);
131 *(path + --length) = '/';
132 }
133
134 pr_debug("kobject: '%s' (%p): %s: path = '%s'\n", kobject_name(kobj),
135 kobj, __func__, path);
136}
137
138/**
139 * kobject_get_path - generate and return the path associated with a given kobj and kset pair.
140 *
141 * @kobj: kobject in question, with which to build the path
142 * @gfp_mask: the allocation type used to allocate the path
143 *
144 * The result must be freed by the caller with kfree().
145 */
146char *kobject_get_path(struct kobject *kobj, gfp_t gfp_mask)
147{
148 char *path;
149 int len;
150
151 len = get_kobj_path_length(kobj);
152 if (len == 0)
153 return NULL;
154 path = kzalloc(len, gfp_mask);
155 if (!path)
156 return NULL;
157 fill_kobj_path(kobj, path, len);
158
159 return path;
160}
161EXPORT_SYMBOL_GPL(kobject_get_path);
162
163/* add the kobject to its kset's list */
164static void kobj_kset_join(struct kobject *kobj)
165{
166 if (!kobj->kset)
167 return;
168
169 kset_get(kobj->kset);
170 spin_lock(&kobj->kset->list_lock);
171 list_add_tail(&kobj->entry, &kobj->kset->list);
172 spin_unlock(&kobj->kset->list_lock);
173}
174
175/* remove the kobject from its kset's list */
176static void kobj_kset_leave(struct kobject *kobj)
177{
178 if (!kobj->kset)
179 return;
180
181 spin_lock(&kobj->kset->list_lock);
182 list_del_init(&kobj->entry);
183 spin_unlock(&kobj->kset->list_lock);
184 kset_put(kobj->kset);
185}
186
187static void kobject_init_internal(struct kobject *kobj)
188{
189 if (!kobj)
190 return;
191 kref_init(&kobj->kref);
192 INIT_LIST_HEAD(&kobj->entry);
193 kobj->state_in_sysfs = 0;
194 kobj->state_add_uevent_sent = 0;
195 kobj->state_remove_uevent_sent = 0;
196 kobj->state_initialized = 1;
197}
198
199
200static int kobject_add_internal(struct kobject *kobj)
201{
202 int error = 0;
203 struct kobject *parent;
204
205 if (!kobj)
206 return -ENOENT;
207
208 if (!kobj->name || !kobj->name[0]) {
209 WARN(1, "kobject: (%p): attempted to be registered with empty "
210 "name!\n", kobj);
211 return -EINVAL;
212 }
213
214 parent = kobject_get(kobj->parent);
215
216 /* join kset if set, use it as parent if we do not already have one */
217 if (kobj->kset) {
218 if (!parent)
219 parent = kobject_get(&kobj->kset->kobj);
220 kobj_kset_join(kobj);
221 kobj->parent = parent;
222 }
223
224 pr_debug("kobject: '%s' (%p): %s: parent: '%s', set: '%s'\n",
225 kobject_name(kobj), kobj, __func__,
226 parent ? kobject_name(parent) : "<NULL>",
227 kobj->kset ? kobject_name(&kobj->kset->kobj) : "<NULL>");
228
229 error = create_dir(kobj);
230 if (error) {
231 kobj_kset_leave(kobj);
232 kobject_put(parent);
233 kobj->parent = NULL;
234
235 /* be noisy on error issues */
236 if (error == -EEXIST)
237 WARN(1, "%s failed for %s with "
238 "-EEXIST, don't try to register things with "
239 "the same name in the same directory.\n",
240 __func__, kobject_name(kobj));
241 else
242 WARN(1, "%s failed for %s (error: %d parent: %s)\n",
243 __func__, kobject_name(kobj), error,
244 parent ? kobject_name(parent) : "'none'");
245 } else
246 kobj->state_in_sysfs = 1;
247
248 return error;
249}
250
251/**
252 * kobject_set_name_vargs - Set the name of an kobject
253 * @kobj: struct kobject to set the name of
254 * @fmt: format string used to build the name
255 * @vargs: vargs to format the string.
256 */
257int kobject_set_name_vargs(struct kobject *kobj, const char *fmt,
258 va_list vargs)
259{
260 const char *old_name = kobj->name;
261 char *s;
262
263 if (kobj->name && !fmt)
264 return 0;
265
266 kobj->name = kvasprintf(GFP_KERNEL, fmt, vargs);
267 if (!kobj->name) {
268 kobj->name = old_name;
269 return -ENOMEM;
270 }
271
272 /* ewww... some of these buggers have '/' in the name ... */
273 while ((s = strchr(kobj->name, '/')))
274 s[0] = '!';
275
276 kfree(old_name);
277 return 0;
278}
279
280/**
281 * kobject_set_name - Set the name of a kobject
282 * @kobj: struct kobject to set the name of
283 * @fmt: format string used to build the name
284 *
285 * This sets the name of the kobject. If you have already added the
286 * kobject to the system, you must call kobject_rename() in order to
287 * change the name of the kobject.
288 */
289int kobject_set_name(struct kobject *kobj, const char *fmt, ...)
290{
291 va_list vargs;
292 int retval;
293
294 va_start(vargs, fmt);
295 retval = kobject_set_name_vargs(kobj, fmt, vargs);
296 va_end(vargs);
297
298 return retval;
299}
300EXPORT_SYMBOL(kobject_set_name);
301
302/**
303 * kobject_init - initialize a kobject structure
304 * @kobj: pointer to the kobject to initialize
305 * @ktype: pointer to the ktype for this kobject.
306 *
307 * This function will properly initialize a kobject such that it can then
308 * be passed to the kobject_add() call.
309 *
310 * After this function is called, the kobject MUST be cleaned up by a call
311 * to kobject_put(), not by a call to kfree directly to ensure that all of
312 * the memory is cleaned up properly.
313 */
314void kobject_init(struct kobject *kobj, struct kobj_type *ktype)
315{
316 char *err_str;
317
318 if (!kobj) {
319 err_str = "invalid kobject pointer!";
320 goto error;
321 }
322 if (!ktype) {
323 err_str = "must have a ktype to be initialized properly!\n";
324 goto error;
325 }
326 if (kobj->state_initialized) {
327 /* do not error out as sometimes we can recover */
328 printk(KERN_ERR "kobject (%p): tried to init an initialized "
329 "object, something is seriously wrong.\n", kobj);
330 dump_stack();
331 }
332
333 kobject_init_internal(kobj);
334 kobj->ktype = ktype;
335 return;
336
337error:
338 printk(KERN_ERR "kobject (%p): %s\n", kobj, err_str);
339 dump_stack();
340}
341EXPORT_SYMBOL(kobject_init);
342
343static int kobject_add_varg(struct kobject *kobj, struct kobject *parent,
344 const char *fmt, va_list vargs)
345{
346 int retval;
347
348 retval = kobject_set_name_vargs(kobj, fmt, vargs);
349 if (retval) {
350 printk(KERN_ERR "kobject: can not set name properly!\n");
351 return retval;
352 }
353 kobj->parent = parent;
354 return kobject_add_internal(kobj);
355}
356
357/**
358 * kobject_add - the main kobject add function
359 * @kobj: the kobject to add
360 * @parent: pointer to the parent of the kobject.
361 * @fmt: format to name the kobject with.
362 *
363 * The kobject name is set and added to the kobject hierarchy in this
364 * function.
365 *
366 * If @parent is set, then the parent of the @kobj will be set to it.
367 * If @parent is NULL, then the parent of the @kobj will be set to the
368 * kobject associated with the kset assigned to this kobject. If no kset
369 * is assigned to the kobject, then the kobject will be located in the
370 * root of the sysfs tree.
371 *
372 * If this function returns an error, kobject_put() must be called to
373 * properly clean up the memory associated with the object.
374 * Under no instance should the kobject that is passed to this function
375 * be directly freed with a call to kfree(), that can leak memory.
376 *
377 * Note, no "add" uevent will be created with this call, the caller should set
378 * up all of the necessary sysfs files for the object and then call
379 * kobject_uevent() with the UEVENT_ADD parameter to ensure that
380 * userspace is properly notified of this kobject's creation.
381 */
382int kobject_add(struct kobject *kobj, struct kobject *parent,
383 const char *fmt, ...)
384{
385 va_list args;
386 int retval;
387
388 if (!kobj)
389 return -EINVAL;
390
391 if (!kobj->state_initialized) {
392 printk(KERN_ERR "kobject '%s' (%p): tried to add an "
393 "uninitialized object, something is seriously wrong.\n",
394 kobject_name(kobj), kobj);
395 dump_stack();
396 return -EINVAL;
397 }
398 va_start(args, fmt);
399 retval = kobject_add_varg(kobj, parent, fmt, args);
400 va_end(args);
401
402 return retval;
403}
404EXPORT_SYMBOL(kobject_add);
405
406/**
407 * kobject_init_and_add - initialize a kobject structure and add it to the kobject hierarchy
408 * @kobj: pointer to the kobject to initialize
409 * @ktype: pointer to the ktype for this kobject.
410 * @parent: pointer to the parent of this kobject.
411 * @fmt: the name of the kobject.
412 *
413 * This function combines the call to kobject_init() and
414 * kobject_add(). The same type of error handling after a call to
415 * kobject_add() and kobject lifetime rules are the same here.
416 */
417int kobject_init_and_add(struct kobject *kobj, struct kobj_type *ktype,
418 struct kobject *parent, const char *fmt, ...)
419{
420 va_list args;
421 int retval;
422
423 kobject_init(kobj, ktype);
424
425 va_start(args, fmt);
426 retval = kobject_add_varg(kobj, parent, fmt, args);
427 va_end(args);
428
429 return retval;
430}
431EXPORT_SYMBOL_GPL(kobject_init_and_add);
432
433/**
434 * kobject_rename - change the name of an object
435 * @kobj: object in question.
436 * @new_name: object's new name
437 *
438 * It is the responsibility of the caller to provide mutual
439 * exclusion between two different calls of kobject_rename
440 * on the same kobject and to ensure that new_name is valid and
441 * won't conflict with other kobjects.
442 */
443int kobject_rename(struct kobject *kobj, const char *new_name)
444{
445 int error = 0;
446 const char *devpath = NULL;
447 const char *dup_name = NULL, *name;
448 char *devpath_string = NULL;
449 char *envp[2];
450
451 kobj = kobject_get(kobj);
452 if (!kobj)
453 return -EINVAL;
454 if (!kobj->parent)
455 return -EINVAL;
456
457 devpath = kobject_get_path(kobj, GFP_KERNEL);
458 if (!devpath) {
459 error = -ENOMEM;
460 goto out;
461 }
462 devpath_string = kmalloc(strlen(devpath) + 15, GFP_KERNEL);
463 if (!devpath_string) {
464 error = -ENOMEM;
465 goto out;
466 }
467 sprintf(devpath_string, "DEVPATH_OLD=%s", devpath);
468 envp[0] = devpath_string;
469 envp[1] = NULL;
470
471 name = dup_name = kstrdup(new_name, GFP_KERNEL);
472 if (!name) {
473 error = -ENOMEM;
474 goto out;
475 }
476
477 error = sysfs_rename_dir_ns(kobj, new_name, kobject_namespace(kobj));
478 if (error)
479 goto out;
480
481 /* Install the new kobject name */
482 dup_name = kobj->name;
483 kobj->name = name;
484
485 /* This function is mostly/only used for network interface.
486 * Some hotplug package track interfaces by their name and
487 * therefore want to know when the name is changed by the user. */
488 kobject_uevent_env(kobj, KOBJ_MOVE, envp);
489
490out:
491 kfree(dup_name);
492 kfree(devpath_string);
493 kfree(devpath);
494 kobject_put(kobj);
495
496 return error;
497}
498EXPORT_SYMBOL_GPL(kobject_rename);
499
500/**
501 * kobject_move - move object to another parent
502 * @kobj: object in question.
503 * @new_parent: object's new parent (can be NULL)
504 */
505int kobject_move(struct kobject *kobj, struct kobject *new_parent)
506{
507 int error;
508 struct kobject *old_parent;
509 const char *devpath = NULL;
510 char *devpath_string = NULL;
511 char *envp[2];
512
513 kobj = kobject_get(kobj);
514 if (!kobj)
515 return -EINVAL;
516 new_parent = kobject_get(new_parent);
517 if (!new_parent) {
518 if (kobj->kset)
519 new_parent = kobject_get(&kobj->kset->kobj);
520 }
521
522 /* old object path */
523 devpath = kobject_get_path(kobj, GFP_KERNEL);
524 if (!devpath) {
525 error = -ENOMEM;
526 goto out;
527 }
528 devpath_string = kmalloc(strlen(devpath) + 15, GFP_KERNEL);
529 if (!devpath_string) {
530 error = -ENOMEM;
531 goto out;
532 }
533 sprintf(devpath_string, "DEVPATH_OLD=%s", devpath);
534 envp[0] = devpath_string;
535 envp[1] = NULL;
536 error = sysfs_move_dir_ns(kobj, new_parent, kobject_namespace(kobj));
537 if (error)
538 goto out;
539 old_parent = kobj->parent;
540 kobj->parent = new_parent;
541 new_parent = NULL;
542 kobject_put(old_parent);
543 kobject_uevent_env(kobj, KOBJ_MOVE, envp);
544out:
545 kobject_put(new_parent);
546 kobject_put(kobj);
547 kfree(devpath_string);
548 kfree(devpath);
549 return error;
550}
551
552/**
553 * kobject_del - unlink kobject from hierarchy.
554 * @kobj: object.
555 */
556void kobject_del(struct kobject *kobj)
557{
558 struct kernfs_node *sd;
559
560 if (!kobj)
561 return;
562
563 sd = kobj->sd;
564 sysfs_remove_dir(kobj);
565 sysfs_put(sd);
566
567 kobj->state_in_sysfs = 0;
568 kobj_kset_leave(kobj);
569 kobject_put(kobj->parent);
570 kobj->parent = NULL;
571}
572
573/**
574 * kobject_get - increment refcount for object.
575 * @kobj: object.
576 */
577struct kobject *kobject_get(struct kobject *kobj)
578{
579 if (kobj)
580 kref_get(&kobj->kref);
581 return kobj;
582}
583
584static struct kobject * __must_check kobject_get_unless_zero(struct kobject *kobj)
585{
586 if (!kref_get_unless_zero(&kobj->kref))
587 kobj = NULL;
588 return kobj;
589}
590
591/*
592 * kobject_cleanup - free kobject resources.
593 * @kobj: object to cleanup
594 */
595static void kobject_cleanup(struct kobject *kobj)
596{
597 struct kobj_type *t = get_ktype(kobj);
598 const char *name = kobj->name;
599
600 pr_debug("kobject: '%s' (%p): %s, parent %p\n",
601 kobject_name(kobj), kobj, __func__, kobj->parent);
602
603 if (t && !t->release)
604 pr_debug("kobject: '%s' (%p): does not have a release() "
605 "function, it is broken and must be fixed.\n",
606 kobject_name(kobj), kobj);
607
608 /* send "remove" if the caller did not do it but sent "add" */
609 if (kobj->state_add_uevent_sent && !kobj->state_remove_uevent_sent) {
610 pr_debug("kobject: '%s' (%p): auto cleanup 'remove' event\n",
611 kobject_name(kobj), kobj);
612 kobject_uevent(kobj, KOBJ_REMOVE);
613 }
614
615 /* remove from sysfs if the caller did not do it */
616 if (kobj->state_in_sysfs) {
617 pr_debug("kobject: '%s' (%p): auto cleanup kobject_del\n",
618 kobject_name(kobj), kobj);
619 kobject_del(kobj);
620 }
621
622 if (t && t->release) {
623 pr_debug("kobject: '%s' (%p): calling ktype release\n",
624 kobject_name(kobj), kobj);
625 t->release(kobj);
626 }
627
628 /* free name if we allocated it */
629 if (name) {
630 pr_debug("kobject: '%s': free name\n", name);
631 kfree(name);
632 }
633}
634
635#ifdef CONFIG_DEBUG_KOBJECT_RELEASE
636static void kobject_delayed_cleanup(struct work_struct *work)
637{
638 kobject_cleanup(container_of(to_delayed_work(work),
639 struct kobject, release));
640}
641#endif
642
643static void kobject_release(struct kref *kref)
644{
645 struct kobject *kobj = container_of(kref, struct kobject, kref);
646#ifdef CONFIG_DEBUG_KOBJECT_RELEASE
647 unsigned long delay = HZ + HZ * (get_random_int() & 0x3);
648 pr_info("kobject: '%s' (%p): %s, parent %p (delayed %ld)\n",
649 kobject_name(kobj), kobj, __func__, kobj->parent, delay);
650 INIT_DELAYED_WORK(&kobj->release, kobject_delayed_cleanup);
651
652 schedule_delayed_work(&kobj->release, delay);
653#else
654 kobject_cleanup(kobj);
655#endif
656}
657
658/**
659 * kobject_put - decrement refcount for object.
660 * @kobj: object.
661 *
662 * Decrement the refcount, and if 0, call kobject_cleanup().
663 */
664void kobject_put(struct kobject *kobj)
665{
666 if (kobj) {
667 if (!kobj->state_initialized)
668 WARN(1, KERN_WARNING "kobject: '%s' (%p): is not "
669 "initialized, yet kobject_put() is being "
670 "called.\n", kobject_name(kobj), kobj);
671 kref_put(&kobj->kref, kobject_release);
672 }
673}
674
675static void dynamic_kobj_release(struct kobject *kobj)
676{
677 pr_debug("kobject: (%p): %s\n", kobj, __func__);
678 kfree(kobj);
679}
680
681static struct kobj_type dynamic_kobj_ktype = {
682 .release = dynamic_kobj_release,
683 .sysfs_ops = &kobj_sysfs_ops,
684};
685
686/**
687 * kobject_create - create a struct kobject dynamically
688 *
689 * This function creates a kobject structure dynamically and sets it up
690 * to be a "dynamic" kobject with a default release function set up.
691 *
692 * If the kobject was not able to be created, NULL will be returned.
693 * The kobject structure returned from here must be cleaned up with a
694 * call to kobject_put() and not kfree(), as kobject_init() has
695 * already been called on this structure.
696 */
697struct kobject *kobject_create(void)
698{
699 struct kobject *kobj;
700
701 kobj = kzalloc(sizeof(*kobj), GFP_KERNEL);
702 if (!kobj)
703 return NULL;
704
705 kobject_init(kobj, &dynamic_kobj_ktype);
706 return kobj;
707}
708
709/**
710 * kobject_create_and_add - create a struct kobject dynamically and register it with sysfs
711 *
712 * @name: the name for the kobject
713 * @parent: the parent kobject of this kobject, if any.
714 *
715 * This function creates a kobject structure dynamically and registers it
716 * with sysfs. When you are finished with this structure, call
717 * kobject_put() and the structure will be dynamically freed when
718 * it is no longer being used.
719 *
720 * If the kobject was not able to be created, NULL will be returned.
721 */
722struct kobject *kobject_create_and_add(const char *name, struct kobject *parent)
723{
724 struct kobject *kobj;
725 int retval;
726
727 kobj = kobject_create();
728 if (!kobj)
729 return NULL;
730
731 retval = kobject_add(kobj, parent, "%s", name);
732 if (retval) {
733 printk(KERN_WARNING "%s: kobject_add error: %d\n",
734 __func__, retval);
735 kobject_put(kobj);
736 kobj = NULL;
737 }
738 return kobj;
739}
740EXPORT_SYMBOL_GPL(kobject_create_and_add);
741
742/**
743 * kset_init - initialize a kset for use
744 * @k: kset
745 */
746void kset_init(struct kset *k)
747{
748 kobject_init_internal(&k->kobj);
749 INIT_LIST_HEAD(&k->list);
750 spin_lock_init(&k->list_lock);
751}
752
753/* default kobject attribute operations */
754static ssize_t kobj_attr_show(struct kobject *kobj, struct attribute *attr,
755 char *buf)
756{
757 struct kobj_attribute *kattr;
758 ssize_t ret = -EIO;
759
760 kattr = container_of(attr, struct kobj_attribute, attr);
761 if (kattr->show)
762 ret = kattr->show(kobj, kattr, buf);
763 return ret;
764}
765
766static ssize_t kobj_attr_store(struct kobject *kobj, struct attribute *attr,
767 const char *buf, size_t count)
768{
769 struct kobj_attribute *kattr;
770 ssize_t ret = -EIO;
771
772 kattr = container_of(attr, struct kobj_attribute, attr);
773 if (kattr->store)
774 ret = kattr->store(kobj, kattr, buf, count);
775 return ret;
776}
777
778const struct sysfs_ops kobj_sysfs_ops = {
779 .show = kobj_attr_show,
780 .store = kobj_attr_store,
781};
782EXPORT_SYMBOL_GPL(kobj_sysfs_ops);
783
784/**
785 * kset_register - initialize and add a kset.
786 * @k: kset.
787 */
788int kset_register(struct kset *k)
789{
790 int err;
791
792 if (!k)
793 return -EINVAL;
794
795 kset_init(k);
796 err = kobject_add_internal(&k->kobj);
797 if (err)
798 return err;
799 kobject_uevent(&k->kobj, KOBJ_ADD);
800 return 0;
801}
802
803/**
804 * kset_unregister - remove a kset.
805 * @k: kset.
806 */
807void kset_unregister(struct kset *k)
808{
809 if (!k)
810 return;
811 kobject_del(&k->kobj);
812 kobject_put(&k->kobj);
813}
814
815/**
816 * kset_find_obj - search for object in kset.
817 * @kset: kset we're looking in.
818 * @name: object's name.
819 *
820 * Lock kset via @kset->subsys, and iterate over @kset->list,
821 * looking for a matching kobject. If matching object is found
822 * take a reference and return the object.
823 */
824struct kobject *kset_find_obj(struct kset *kset, const char *name)
825{
826 struct kobject *k;
827 struct kobject *ret = NULL;
828
829 spin_lock(&kset->list_lock);
830
831 list_for_each_entry(k, &kset->list, entry) {
832 if (kobject_name(k) && !strcmp(kobject_name(k), name)) {
833 ret = kobject_get_unless_zero(k);
834 break;
835 }
836 }
837
838 spin_unlock(&kset->list_lock);
839 return ret;
840}
841
842static void kset_release(struct kobject *kobj)
843{
844 struct kset *kset = container_of(kobj, struct kset, kobj);
845 pr_debug("kobject: '%s' (%p): %s\n",
846 kobject_name(kobj), kobj, __func__);
847 kfree(kset);
848}
849
850static struct kobj_type kset_ktype = {
851 .sysfs_ops = &kobj_sysfs_ops,
852 .release = kset_release,
853};
854
855/**
856 * kset_create - create a struct kset dynamically
857 *
858 * @name: the name for the kset
859 * @uevent_ops: a struct kset_uevent_ops for the kset
860 * @parent_kobj: the parent kobject of this kset, if any.
861 *
862 * This function creates a kset structure dynamically. This structure can
863 * then be registered with the system and show up in sysfs with a call to
864 * kset_register(). When you are finished with this structure, if
865 * kset_register() has been called, call kset_unregister() and the
866 * structure will be dynamically freed when it is no longer being used.
867 *
868 * If the kset was not able to be created, NULL will be returned.
869 */
870static struct kset *kset_create(const char *name,
871 const struct kset_uevent_ops *uevent_ops,
872 struct kobject *parent_kobj)
873{
874 struct kset *kset;
875 int retval;
876
877 kset = kzalloc(sizeof(*kset), GFP_KERNEL);
878 if (!kset)
879 return NULL;
880 retval = kobject_set_name(&kset->kobj, "%s", name);
881 if (retval) {
882 kfree(kset);
883 return NULL;
884 }
885 kset->uevent_ops = uevent_ops;
886 kset->kobj.parent = parent_kobj;
887
888 /*
889 * The kobject of this kset will have a type of kset_ktype and belong to
890 * no kset itself. That way we can properly free it when it is
891 * finished being used.
892 */
893 kset->kobj.ktype = &kset_ktype;
894 kset->kobj.kset = NULL;
895
896 return kset;
897}
898
899/**
900 * kset_create_and_add - create a struct kset dynamically and add it to sysfs
901 *
902 * @name: the name for the kset
903 * @uevent_ops: a struct kset_uevent_ops for the kset
904 * @parent_kobj: the parent kobject of this kset, if any.
905 *
906 * This function creates a kset structure dynamically and registers it
907 * with sysfs. When you are finished with this structure, call
908 * kset_unregister() and the structure will be dynamically freed when it
909 * is no longer being used.
910 *
911 * If the kset was not able to be created, NULL will be returned.
912 */
913struct kset *kset_create_and_add(const char *name,
914 const struct kset_uevent_ops *uevent_ops,
915 struct kobject *parent_kobj)
916{
917 struct kset *kset;
918 int error;
919
920 kset = kset_create(name, uevent_ops, parent_kobj);
921 if (!kset)
922 return NULL;
923 error = kset_register(kset);
924 if (error) {
925 kfree(kset);
926 return NULL;
927 }
928 return kset;
929}
930EXPORT_SYMBOL_GPL(kset_create_and_add);
931
932
933static DEFINE_SPINLOCK(kobj_ns_type_lock);
934static const struct kobj_ns_type_operations *kobj_ns_ops_tbl[KOBJ_NS_TYPES];
935
936int kobj_ns_type_register(const struct kobj_ns_type_operations *ops)
937{
938 enum kobj_ns_type type = ops->type;
939 int error;
940
941 spin_lock(&kobj_ns_type_lock);
942
943 error = -EINVAL;
944 if (type >= KOBJ_NS_TYPES)
945 goto out;
946
947 error = -EINVAL;
948 if (type <= KOBJ_NS_TYPE_NONE)
949 goto out;
950
951 error = -EBUSY;
952 if (kobj_ns_ops_tbl[type])
953 goto out;
954
955 error = 0;
956 kobj_ns_ops_tbl[type] = ops;
957
958out:
959 spin_unlock(&kobj_ns_type_lock);
960 return error;
961}
962
963int kobj_ns_type_registered(enum kobj_ns_type type)
964{
965 int registered = 0;
966
967 spin_lock(&kobj_ns_type_lock);
968 if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES))
969 registered = kobj_ns_ops_tbl[type] != NULL;
970 spin_unlock(&kobj_ns_type_lock);
971
972 return registered;
973}
974
975const struct kobj_ns_type_operations *kobj_child_ns_ops(struct kobject *parent)
976{
977 const struct kobj_ns_type_operations *ops = NULL;
978
979 if (parent && parent->ktype->child_ns_type)
980 ops = parent->ktype->child_ns_type(parent);
981
982 return ops;
983}
984
985const struct kobj_ns_type_operations *kobj_ns_ops(struct kobject *kobj)
986{
987 return kobj_child_ns_ops(kobj->parent);
988}
989
990bool kobj_ns_current_may_mount(enum kobj_ns_type type)
991{
992 bool may_mount = true;
993
994 spin_lock(&kobj_ns_type_lock);
995 if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
996 kobj_ns_ops_tbl[type])
997 may_mount = kobj_ns_ops_tbl[type]->current_may_mount();
998 spin_unlock(&kobj_ns_type_lock);
999
1000 return may_mount;
1001}
1002
1003void *kobj_ns_grab_current(enum kobj_ns_type type)
1004{
1005 void *ns = NULL;
1006
1007 spin_lock(&kobj_ns_type_lock);
1008 if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
1009 kobj_ns_ops_tbl[type])
1010 ns = kobj_ns_ops_tbl[type]->grab_current_ns();
1011 spin_unlock(&kobj_ns_type_lock);
1012
1013 return ns;
1014}
1015
1016const void *kobj_ns_netlink(enum kobj_ns_type type, struct sock *sk)
1017{
1018 const void *ns = NULL;
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 ns = kobj_ns_ops_tbl[type]->netlink_ns(sk);
1024 spin_unlock(&kobj_ns_type_lock);
1025
1026 return ns;
1027}
1028
1029const void *kobj_ns_initial(enum kobj_ns_type type)
1030{
1031 const 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]->initial_ns();
1037 spin_unlock(&kobj_ns_type_lock);
1038
1039 return ns;
1040}
1041
1042void kobj_ns_drop(enum kobj_ns_type type, void *ns)
1043{
1044 spin_lock(&kobj_ns_type_lock);
1045 if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
1046 kobj_ns_ops_tbl[type] && kobj_ns_ops_tbl[type]->drop_ns)
1047 kobj_ns_ops_tbl[type]->drop_ns(ns);
1048 spin_unlock(&kobj_ns_type_lock);
1049}
1050
1051EXPORT_SYMBOL(kobject_get);
1052EXPORT_SYMBOL(kobject_put);
1053EXPORT_SYMBOL(kobject_del);
1054
1055EXPORT_SYMBOL(kset_register);
1056EXPORT_SYMBOL(kset_unregister);