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Kobject: remove kobject_add() as no one uses it anymore
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CommitLineData
1da177e4
LT
1/*
2 * kobject.c - library routines for handling generic kernel objects
3 *
4 * Copyright (c) 2002-2003 Patrick Mochel <mochel@osdl.org>
f0e7e1bd
GKH
5 * Copyright (c) 2006-2007 Greg Kroah-Hartman <greg@kroah.com>
6 * Copyright (c) 2006-2007 Novell Inc.
1da177e4
LT
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>
4e57b681 19#include <linux/slab.h>
1da177e4
LT
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
26 * are associated with an object that registers with them.
27 * This is a helper called during object registration that
28 * loops through the default attributes of the subsystem
29 * and creates attributes files for them in sysfs.
30 *
31 */
32
33static int populate_dir(struct kobject * kobj)
34{
35 struct kobj_type * t = get_ktype(kobj);
36 struct attribute * attr;
37 int error = 0;
38 int i;
39
40 if (t && t->default_attrs) {
41 for (i = 0; (attr = t->default_attrs[i]) != NULL; i++) {
42 if ((error = sysfs_create_file(kobj,attr)))
43 break;
44 }
45 }
46 return error;
47}
48
90bc6135 49static int create_dir(struct kobject * kobj)
1da177e4
LT
50{
51 int error = 0;
52 if (kobject_name(kobj)) {
90bc6135 53 error = sysfs_create_dir(kobj);
1da177e4
LT
54 if (!error) {
55 if ((error = populate_dir(kobj)))
56 sysfs_remove_dir(kobj);
57 }
58 }
59 return error;
60}
61
62static inline struct kobject * to_kobj(struct list_head * entry)
63{
64 return container_of(entry,struct kobject,entry);
65}
66
67static int get_kobj_path_length(struct kobject *kobj)
68{
69 int length = 1;
70 struct kobject * parent = kobj;
71
72 /* walk up the ancestors until we hit the one pointing to the
73 * root.
74 * Add 1 to strlen for leading '/' of each level.
75 */
76 do {
b365b3da
CE
77 if (kobject_name(parent) == NULL)
78 return 0;
1da177e4
LT
79 length += strlen(kobject_name(parent)) + 1;
80 parent = parent->parent;
81 } while (parent);
82 return length;
83}
84
85static void fill_kobj_path(struct kobject *kobj, char *path, int length)
86{
87 struct kobject * parent;
88
89 --length;
90 for (parent = kobj; parent; parent = parent->parent) {
91 int cur = strlen(kobject_name(parent));
92 /* back up enough to print this name with '/' */
93 length -= cur;
94 strncpy (path + length, kobject_name(parent), cur);
95 *(path + --length) = '/';
96 }
97
9f66fa2a
GKH
98 pr_debug("kobject: '%s' (%p): %s: path = '%s'\n", kobject_name(kobj),
99 kobj, __FUNCTION__,path);
1da177e4
LT
100}
101
102/**
72fd4a35 103 * kobject_get_path - generate and return the path associated with a given kobj and kset pair.
1da177e4
LT
104 *
105 * @kobj: kobject in question, with which to build the path
106 * @gfp_mask: the allocation type used to allocate the path
72fd4a35
RD
107 *
108 * The result must be freed by the caller with kfree().
1da177e4 109 */
fd4f2df2 110char *kobject_get_path(struct kobject *kobj, gfp_t gfp_mask)
1da177e4
LT
111{
112 char *path;
113 int len;
114
115 len = get_kobj_path_length(kobj);
b365b3da
CE
116 if (len == 0)
117 return NULL;
4668edc3 118 path = kzalloc(len, gfp_mask);
1da177e4
LT
119 if (!path)
120 return NULL;
1da177e4
LT
121 fill_kobj_path(kobj, path, len);
122
123 return path;
124}
80fc9f53 125EXPORT_SYMBOL_GPL(kobject_get_path);
1da177e4
LT
126
127/**
128 * kobject_init - initialize object.
129 * @kobj: object in question.
130 */
131void kobject_init(struct kobject * kobj)
132{
31b9025a
GKH
133 if (!kobj)
134 return;
1da177e4
LT
135 kref_init(&kobj->kref);
136 INIT_LIST_HEAD(&kobj->entry);
1da177e4
LT
137}
138
139
140/**
141 * unlink - remove kobject from kset list.
142 * @kobj: kobject.
143 *
144 * Remove the kobject from the kset list and decrement
145 * its parent's refcount.
146 * This is separated out, so we can use it in both
9e7bbccd 147 * kobject_del() and kobject_add_internal() on error.
1da177e4
LT
148 */
149
150static void unlink(struct kobject * kobj)
151{
09f82ea9
AS
152 struct kobject *parent = kobj->parent;
153
1da177e4
LT
154 if (kobj->kset) {
155 spin_lock(&kobj->kset->list_lock);
156 list_del_init(&kobj->entry);
157 spin_unlock(&kobj->kset->list_lock);
158 }
09f82ea9 159 kobj->parent = NULL;
1da177e4 160 kobject_put(kobj);
09f82ea9 161 kobject_put(parent);
1da177e4
LT
162}
163
9e7bbccd 164static int kobject_add_internal(struct kobject *kobj)
1da177e4
LT
165{
166 int error = 0;
167 struct kobject * parent;
168
169 if (!(kobj = kobject_get(kobj)))
170 return -ENOENT;
171 if (!kobj->k_name)
ce2c9cb0 172 kobject_set_name(kobj, "NO_NAME");
13507701 173 if (!*kobj->k_name) {
9f66fa2a
GKH
174 pr_debug("kobject (%p) attempted to be registered with no "
175 "name!\n", kobj);
c171fef5 176 WARN_ON(1);
88db4721 177 kobject_put(kobj);
c171fef5
GKH
178 return -EINVAL;
179 }
1da177e4
LT
180 parent = kobject_get(kobj->parent);
181
9f66fa2a
GKH
182 pr_debug("kobject: '%s' (%p): %s: parent: '%s', set: '%s'\n",
183 kobject_name(kobj), kobj, __FUNCTION__,
184 parent ? kobject_name(parent) : "<NULL>",
ce2c9cb0 185 kobj->kset ? kobject_name(&kobj->kset->kobj) : "<NULL>" );
1da177e4
LT
186
187 if (kobj->kset) {
cfb36fff 188 kobj->kset = kset_get(kobj->kset);
1da177e4 189
b727c702 190 if (!parent) {
1da177e4 191 parent = kobject_get(&kobj->kset->kobj);
b727c702
GKH
192 /*
193 * If the kset is our parent, get a second
194 * reference, we drop both the kset and the
195 * parent ref on cleanup
196 */
197 kobject_get(parent);
198 }
1da177e4 199
cfb36fff
GKH
200 spin_lock(&kobj->kset->list_lock);
201 list_add_tail(&kobj->entry, &kobj->kset->list);
1da177e4 202 spin_unlock(&kobj->kset->list_lock);
460f7e9a 203 kobj->parent = parent;
1da177e4 204 }
1da177e4 205
90bc6135 206 error = create_dir(kobj);
1da177e4
LT
207 if (error) {
208 /* unlink does the kobject_put() for us */
209 unlink(kobj);
dcd0da00
GKH
210
211 /* be noisy on error issues */
212 if (error == -EEXIST)
9e7bbccd 213 printk(KERN_ERR "%s failed for %s with "
5c73a3fb
GKH
214 "-EEXIST, don't try to register things with "
215 "the same name in the same directory.\n",
9e7bbccd 216 __FUNCTION__, kobject_name(kobj));
dcd0da00 217 else
9e7bbccd
GKH
218 printk(KERN_ERR "%s failed for %s (%d)\n",
219 __FUNCTION__, kobject_name(kobj), error);
5c73a3fb 220 dump_stack();
1da177e4
LT
221 }
222
223 return error;
224}
225
1da177e4
LT
226/**
227 * kobject_register - initialize and add an object.
228 * @kobj: object in question.
229 */
230
231int kobject_register(struct kobject * kobj)
232{
dcd0da00 233 int error = -EINVAL;
1da177e4
LT
234 if (kobj) {
235 kobject_init(kobj);
236 error = kobject_add(kobj);
dcd0da00 237 if (!error)
312c004d 238 kobject_uevent(kobj, KOBJ_ADD);
dcd0da00 239 }
1da177e4
LT
240 return error;
241}
242
663a4743
GKH
243/**
244 * kobject_set_name_vargs - Set the name of an kobject
245 * @kobj: struct kobject to set the name of
246 * @fmt: format string used to build the name
247 * @vargs: vargs to format the string.
248 */
249static int kobject_set_name_vargs(struct kobject *kobj, const char *fmt,
250 va_list vargs)
251{
252 va_list aq;
253 char *name;
254
255 va_copy(aq, vargs);
256 name = kvasprintf(GFP_KERNEL, fmt, vargs);
257 va_end(aq);
258
259 if (!name)
260 return -ENOMEM;
261
262 /* Free the old name, if necessary. */
263 kfree(kobj->k_name);
264
265 /* Now, set the new name */
266 kobj->k_name = name;
267
268 return 0;
269}
1da177e4
LT
270
271/**
8c4606b1 272 * kobject_set_name - Set the name of a kobject
663a4743 273 * @kobj: struct kobject to set the name of
8c4606b1 274 * @fmt: format string used to build the name
1da177e4 275 *
8c4606b1
GKH
276 * This sets the name of the kobject. If you have already added the
277 * kobject to the system, you must call kobject_rename() in order to
278 * change the name of the kobject.
1da177e4 279 */
663a4743 280int kobject_set_name(struct kobject *kobj, const char *fmt, ...)
1da177e4 281{
1da177e4 282 va_list args;
663a4743 283 int retval;
1da177e4 284
ce2c9cb0 285 va_start(args, fmt);
663a4743 286 retval = kobject_set_name_vargs(kobj, fmt, args);
1da177e4 287 va_end(args);
1da177e4 288
663a4743 289 return retval;
1da177e4 290}
1da177e4
LT
291EXPORT_SYMBOL(kobject_set_name);
292
e86000d0
GKH
293/**
294 * kobject_init_ng - initialize a kobject structure
295 * @kobj: pointer to the kobject to initialize
296 * @ktype: pointer to the ktype for this kobject.
297 *
298 * This function will properly initialize a kobject such that it can then
299 * be passed to the kobject_add() call.
300 *
301 * After this function is called, the kobject MUST be cleaned up by a call
302 * to kobject_put(), not by a call to kfree directly to ensure that all of
303 * the memory is cleaned up properly.
304 */
305void kobject_init_ng(struct kobject *kobj, struct kobj_type *ktype)
306{
307 char *err_str;
308
309 if (!kobj) {
310 err_str = "invalid kobject pointer!";
311 goto error;
312 }
313 if (!ktype) {
314 err_str = "must have a ktype to be initialized properly!\n";
315 goto error;
316 }
317 if (atomic_read(&kobj->kref.refcount)) {
318 /* do not error out as sometimes we can recover */
319 printk(KERN_ERR "kobject: reference count is already set, "
320 "something is seriously wrong.\n");
321 dump_stack();
322 }
323
324 kref_init(&kobj->kref);
325 INIT_LIST_HEAD(&kobj->entry);
326 kobj->ktype = ktype;
327 return;
328
329error:
330 printk(KERN_ERR "kobject: %s\n", err_str);
331 dump_stack();
332}
333EXPORT_SYMBOL(kobject_init_ng);
334
244f6cee
GKH
335static int kobject_add_varg(struct kobject *kobj, struct kobject *parent,
336 const char *fmt, va_list vargs)
337{
338 va_list aq;
339 int retval;
340
341 va_copy(aq, vargs);
342 retval = kobject_set_name_vargs(kobj, fmt, aq);
343 va_end(aq);
344 if (retval) {
345 printk(KERN_ERR "kobject: can not set name properly!\n");
346 return retval;
347 }
348 kobj->parent = parent;
9e7bbccd 349 return kobject_add_internal(kobj);
244f6cee
GKH
350}
351
352/**
353 * kobject_add_ng - the main kobject add function
354 * @kobj: the kobject to add
355 * @parent: pointer to the parent of the kobject.
356 * @fmt: format to name the kobject with.
357 *
358 * The kobject name is set and added to the kobject hierarchy in this
359 * function.
360 *
361 * If @parent is set, then the parent of the @kobj will be set to it.
362 * If @parent is NULL, then the parent of the @kobj will be set to the
363 * kobject associted with the kset assigned to this kobject. If no kset
364 * is assigned to the kobject, then the kobject will be located in the
365 * root of the sysfs tree.
366 *
367 * If this function returns an error, kobject_put() must be called to
368 * properly clean up the memory associated with the object.
369 *
370 * If the function is successful, the only way to properly clean up the
371 * memory is with a call to kobject_del(), in which case, a call to
372 * kobject_put() is not necessary (kobject_del() does the final
373 * kobject_put() to call the release function in the ktype's release
374 * pointer.)
375 *
376 * Under no instance should the kobject that is passed to this function
377 * be directly freed with a call to kfree(), that can leak memory.
378 *
379 * Note, no uevent will be created with this call, the caller should set
380 * up all of the necessary sysfs files for the object and then call
381 * kobject_uevent() with the UEVENT_ADD parameter to ensure that
382 * userspace is properly notified of this kobject's creation.
383 */
384int kobject_add_ng(struct kobject *kobj, struct kobject *parent,
385 const char *fmt, ...)
386{
387 va_list args;
388 int retval;
389
390 if (!kobj)
391 return -EINVAL;
392
393 va_start(args, fmt);
394 retval = kobject_add_varg(kobj, parent, fmt, args);
395 va_end(args);
396
397 return retval;
398}
399EXPORT_SYMBOL(kobject_add_ng);
400
c11c4154
GKH
401/**
402 * kobject_init_and_add - initialize a kobject structure and add it to the kobject hierarchy
403 * @kobj: pointer to the kobject to initialize
404 * @ktype: pointer to the ktype for this kobject.
405 * @parent: pointer to the parent of this kobject.
406 * @fmt: the name of the kobject.
407 *
408 * This function combines the call to kobject_init_ng() and
409 * kobject_add_ng(). The same type of error handling after a call to
410 * kobject_add_ng() and kobject lifetime rules are the same here.
411 */
412int kobject_init_and_add(struct kobject *kobj, struct kobj_type *ktype,
413 struct kobject *parent, const char *fmt, ...)
414{
415 va_list args;
416 int retval;
417
418 kobject_init_ng(kobj, ktype);
419
420 va_start(args, fmt);
421 retval = kobject_add_varg(kobj, parent, fmt, args);
422 va_end(args);
423
424 return retval;
425}
426EXPORT_SYMBOL_GPL(kobject_init_and_add);
427
1da177e4
LT
428/**
429 * kobject_rename - change the name of an object
430 * @kobj: object in question.
431 * @new_name: object's new name
432 */
433
f3b4f3c6 434int kobject_rename(struct kobject * kobj, const char *new_name)
1da177e4
LT
435{
436 int error = 0;
ca2f37db
JT
437 const char *devpath = NULL;
438 char *devpath_string = NULL;
439 char *envp[2];
1da177e4
LT
440
441 kobj = kobject_get(kobj);
442 if (!kobj)
443 return -EINVAL;
b592fcfe
EB
444 if (!kobj->parent)
445 return -EINVAL;
ca2f37db 446
34358c26
GKH
447 /* see if this name is already in use */
448 if (kobj->kset) {
449 struct kobject *temp_kobj;
450 temp_kobj = kset_find_obj(kobj->kset, new_name);
451 if (temp_kobj) {
71409a49
JB
452 printk(KERN_WARNING "kobject '%s' cannot be renamed "
453 "to '%s' as '%s' is already in existence.\n",
34358c26
GKH
454 kobject_name(kobj), new_name, new_name);
455 kobject_put(temp_kobj);
456 return -EINVAL;
457 }
458 }
459
ca2f37db
JT
460 devpath = kobject_get_path(kobj, GFP_KERNEL);
461 if (!devpath) {
462 error = -ENOMEM;
463 goto out;
464 }
465 devpath_string = kmalloc(strlen(devpath) + 15, GFP_KERNEL);
466 if (!devpath_string) {
467 error = -ENOMEM;
468 goto out;
469 }
470 sprintf(devpath_string, "DEVPATH_OLD=%s", devpath);
471 envp[0] = devpath_string;
472 envp[1] = NULL;
ca2f37db 473
90bc6135 474 error = sysfs_rename_dir(kobj, new_name);
ca2f37db
JT
475
476 /* This function is mostly/only used for network interface.
477 * Some hotplug package track interfaces by their name and
478 * therefore want to know when the name is changed by the user. */
479 if (!error)
480 kobject_uevent_env(kobj, KOBJ_MOVE, envp);
481
482out:
483 kfree(devpath_string);
484 kfree(devpath);
b592fcfe
EB
485 kobject_put(kobj);
486
487 return error;
488}
489
8a82472f
CH
490/**
491 * kobject_move - move object to another parent
492 * @kobj: object in question.
c744aeae 493 * @new_parent: object's new parent (can be NULL)
8a82472f
CH
494 */
495
496int kobject_move(struct kobject *kobj, struct kobject *new_parent)
497{
498 int error;
499 struct kobject *old_parent;
500 const char *devpath = NULL;
501 char *devpath_string = NULL;
502 char *envp[2];
503
504 kobj = kobject_get(kobj);
505 if (!kobj)
506 return -EINVAL;
507 new_parent = kobject_get(new_parent);
508 if (!new_parent) {
c744aeae
CH
509 if (kobj->kset)
510 new_parent = kobject_get(&kobj->kset->kobj);
8a82472f
CH
511 }
512 /* old object path */
513 devpath = kobject_get_path(kobj, GFP_KERNEL);
514 if (!devpath) {
515 error = -ENOMEM;
516 goto out;
517 }
518 devpath_string = kmalloc(strlen(devpath) + 15, GFP_KERNEL);
519 if (!devpath_string) {
520 error = -ENOMEM;
521 goto out;
522 }
523 sprintf(devpath_string, "DEVPATH_OLD=%s", devpath);
524 envp[0] = devpath_string;
525 envp[1] = NULL;
526 error = sysfs_move_dir(kobj, new_parent);
527 if (error)
528 goto out;
529 old_parent = kobj->parent;
530 kobj->parent = new_parent;
9e993efb 531 new_parent = NULL;
8a82472f
CH
532 kobject_put(old_parent);
533 kobject_uevent_env(kobj, KOBJ_MOVE, envp);
534out:
9e993efb 535 kobject_put(new_parent);
8a82472f
CH
536 kobject_put(kobj);
537 kfree(devpath_string);
538 kfree(devpath);
539 return error;
540}
541
1da177e4
LT
542/**
543 * kobject_del - unlink kobject from hierarchy.
544 * @kobj: object.
545 */
546
547void kobject_del(struct kobject * kobj)
548{
31b9025a
GKH
549 if (!kobj)
550 return;
1da177e4
LT
551 sysfs_remove_dir(kobj);
552 unlink(kobj);
553}
554
555/**
556 * kobject_unregister - remove object from hierarchy and decrement refcount.
557 * @kobj: object going away.
558 */
559
560void kobject_unregister(struct kobject * kobj)
561{
31b9025a
GKH
562 if (!kobj)
563 return;
9f66fa2a
GKH
564 pr_debug("kobject: '%s' (%p): %s\n",
565 kobject_name(kobj), kobj, __FUNCTION__);
312c004d 566 kobject_uevent(kobj, KOBJ_REMOVE);
1da177e4
LT
567 kobject_del(kobj);
568 kobject_put(kobj);
569}
570
571/**
572 * kobject_get - increment refcount for object.
573 * @kobj: object.
574 */
575
576struct kobject * kobject_get(struct kobject * kobj)
577{
578 if (kobj)
579 kref_get(&kobj->kref);
580 return kobj;
581}
582
18041f47
GKH
583/*
584 * kobject_cleanup - free kobject resources.
585 * @kobj: object to cleanup
1da177e4 586 */
18041f47 587static void kobject_cleanup(struct kobject *kobj)
1da177e4
LT
588{
589 struct kobj_type * t = get_ktype(kobj);
590 struct kset * s = kobj->kset;
ce2c9cb0 591 const char *name = kobj->k_name;
1da177e4 592
9f66fa2a
GKH
593 pr_debug("kobject: '%s' (%p): %s\n",
594 kobject_name(kobj), kobj, __FUNCTION__);
ce2c9cb0 595 if (t && t->release) {
1da177e4 596 t->release(kobj);
ce2c9cb0
GKH
597 /* If we have a release function, we can guess that this was
598 * not a statically allocated kobject, so we should be safe to
599 * free the name */
600 kfree(name);
601 }
1da177e4
LT
602 if (s)
603 kset_put(s);
1da177e4
LT
604}
605
606static void kobject_release(struct kref *kref)
607{
608 kobject_cleanup(container_of(kref, struct kobject, kref));
609}
610
611/**
612 * kobject_put - decrement refcount for object.
613 * @kobj: object.
614 *
615 * Decrement the refcount, and if 0, call kobject_cleanup().
616 */
617void kobject_put(struct kobject * kobj)
618{
619 if (kobj)
620 kref_put(&kobj->kref, kobject_release);
621}
622
3f9e3ee9 623static void dynamic_kobj_release(struct kobject *kobj)
7423172a 624{
9f66fa2a
GKH
625 pr_debug("kobject: '%s' (%p): %s\n",
626 kobject_name(kobj), kobj, __FUNCTION__);
7423172a
JN
627 kfree(kobj);
628}
629
3f9e3ee9 630static struct kobj_type dynamic_kobj_ktype = {
386f275f
KS
631 .release = dynamic_kobj_release,
632 .sysfs_ops = &kobj_sysfs_ops,
7423172a
JN
633};
634
43968d2f 635/**
3f9e3ee9
GKH
636 * kobject_create - create a struct kobject dynamically
637 *
638 * This function creates a kobject structure dynamically and sets it up
639 * to be a "dynamic" kobject with a default release function set up.
640 *
641 * If the kobject was not able to be created, NULL will be returned.
43968d2f
GKH
642 * The kobject structure returned from here must be cleaned up with a
643 * call to kobject_put() and not kfree(), as kobject_init_ng() has
644 * already been called on this structure.
3f9e3ee9 645 */
43968d2f 646struct kobject *kobject_create(void)
3f9e3ee9
GKH
647{
648 struct kobject *kobj;
649
650 kobj = kzalloc(sizeof(*kobj), GFP_KERNEL);
651 if (!kobj)
652 return NULL;
653
654 kobject_init_ng(kobj, &dynamic_kobj_ktype);
655 return kobj;
656}
657
658/**
659 * kobject_create_and_add - create a struct kobject dynamically and register it with sysfs
660 *
661 * @name: the name for the kset
662 * @parent: the parent kobject of this kobject, if any.
663 *
664 * This function creates a kset structure dynamically and registers it
665 * with sysfs. When you are finished with this structure, call
666 * kobject_unregister() and the structure will be dynamically freed when
667 * it is no longer being used.
668 *
669 * If the kobject was not able to be created, NULL will be returned.
670 */
671struct kobject *kobject_create_and_add(const char *name, struct kobject *parent)
672{
673 struct kobject *kobj;
674 int retval;
675
676 kobj = kobject_create();
677 if (!kobj)
678 return NULL;
679
680 retval = kobject_add_ng(kobj, parent, "%s", name);
681 if (retval) {
682 printk(KERN_WARNING "%s: kobject_add error: %d\n",
683 __FUNCTION__, retval);
684 kobject_put(kobj);
685 kobj = NULL;
686 }
687 return kobj;
688}
689EXPORT_SYMBOL_GPL(kobject_create_and_add);
690
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691/**
692 * kset_init - initialize a kset for use
693 * @k: kset
694 */
695
696void kset_init(struct kset * k)
697{
698 kobject_init(&k->kobj);
699 INIT_LIST_HEAD(&k->list);
700 spin_lock_init(&k->list_lock);
701}
702
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703/* default kobject attribute operations */
704static ssize_t kobj_attr_show(struct kobject *kobj, struct attribute *attr,
705 char *buf)
706{
707 struct kobj_attribute *kattr;
708 ssize_t ret = -EIO;
709
710 kattr = container_of(attr, struct kobj_attribute, attr);
711 if (kattr->show)
712 ret = kattr->show(kobj, kattr, buf);
713 return ret;
714}
715
716static ssize_t kobj_attr_store(struct kobject *kobj, struct attribute *attr,
717 const char *buf, size_t count)
718{
719 struct kobj_attribute *kattr;
720 ssize_t ret = -EIO;
721
722 kattr = container_of(attr, struct kobj_attribute, attr);
723 if (kattr->store)
724 ret = kattr->store(kobj, kattr, buf, count);
725 return ret;
726}
727
728struct sysfs_ops kobj_sysfs_ops = {
729 .show = kobj_attr_show,
730 .store = kobj_attr_store,
731};
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732
733/**
734 * kset_add - add a kset object to the hierarchy.
735 * @k: kset.
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736 */
737
738int kset_add(struct kset * k)
739{
9e7bbccd 740 return kobject_add_internal(&k->kobj);
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741}
742
743
744/**
745 * kset_register - initialize and add a kset.
746 * @k: kset.
747 */
748
749int kset_register(struct kset * k)
750{
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751 int err;
752
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753 if (!k)
754 return -EINVAL;
80f03e34 755
1da177e4 756 kset_init(k);
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757 err = kset_add(k);
758 if (err)
759 return err;
760 kobject_uevent(&k->kobj, KOBJ_ADD);
761 return 0;
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762}
763
764
765/**
766 * kset_unregister - remove a kset.
767 * @k: kset.
768 */
769
770void kset_unregister(struct kset * k)
771{
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772 if (!k)
773 return;
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774 kobject_unregister(&k->kobj);
775}
776
777
778/**
779 * kset_find_obj - search for object in kset.
780 * @kset: kset we're looking in.
781 * @name: object's name.
782 *
783 * Lock kset via @kset->subsys, and iterate over @kset->list,
784 * looking for a matching kobject. If matching object is found
785 * take a reference and return the object.
786 */
787
788struct kobject * kset_find_obj(struct kset * kset, const char * name)
789{
790 struct list_head * entry;
791 struct kobject * ret = NULL;
792
793 spin_lock(&kset->list_lock);
794 list_for_each(entry,&kset->list) {
795 struct kobject * k = to_kobj(entry);
796 if (kobject_name(k) && !strcmp(kobject_name(k),name)) {
797 ret = kobject_get(k);
798 break;
799 }
800 }
801 spin_unlock(&kset->list_lock);
802 return ret;
803}
804
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805static void kset_release(struct kobject *kobj)
806{
807 struct kset *kset = container_of(kobj, struct kset, kobj);
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808 pr_debug("kobject: '%s' (%p): %s\n",
809 kobject_name(kobj), kobj, __FUNCTION__);
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810 kfree(kset);
811}
812
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813static struct kobj_type kset_ktype = {
814 .sysfs_ops = &kobj_sysfs_ops,
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815 .release = kset_release,
816};
817
818/**
819 * kset_create - create a struct kset dynamically
820 *
821 * @name: the name for the kset
822 * @uevent_ops: a struct kset_uevent_ops for the kset
823 * @parent_kobj: the parent kobject of this kset, if any.
824 *
825 * This function creates a kset structure dynamically. This structure can
826 * then be registered with the system and show up in sysfs with a call to
827 * kset_register(). When you are finished with this structure, if
828 * kset_register() has been called, call kset_unregister() and the
829 * structure will be dynamically freed when it is no longer being used.
830 *
831 * If the kset was not able to be created, NULL will be returned.
832 */
833static struct kset *kset_create(const char *name,
834 struct kset_uevent_ops *uevent_ops,
835 struct kobject *parent_kobj)
836{
837 struct kset *kset;
838
839 kset = kzalloc(sizeof(*kset), GFP_KERNEL);
840 if (!kset)
841 return NULL;
842 kobject_set_name(&kset->kobj, name);
843 kset->uevent_ops = uevent_ops;
844 kset->kobj.parent = parent_kobj;
845
846 /*
386f275f 847 * The kobject of this kset will have a type of kset_ktype and belong to
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848 * no kset itself. That way we can properly free it when it is
849 * finished being used.
850 */
386f275f 851 kset->kobj.ktype = &kset_ktype;
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852 kset->kobj.kset = NULL;
853
854 return kset;
855}
856
857/**
858 * kset_create_and_add - create a struct kset dynamically and add it to sysfs
859 *
860 * @name: the name for the kset
861 * @uevent_ops: a struct kset_uevent_ops for the kset
862 * @parent_kobj: the parent kobject of this kset, if any.
863 *
864 * This function creates a kset structure dynamically and registers it
865 * with sysfs. When you are finished with this structure, call
866 * kset_unregister() and the structure will be dynamically freed when it
867 * is no longer being used.
868 *
869 * If the kset was not able to be created, NULL will be returned.
870 */
871struct kset *kset_create_and_add(const char *name,
872 struct kset_uevent_ops *uevent_ops,
873 struct kobject *parent_kobj)
874{
875 struct kset *kset;
876 int error;
877
878 kset = kset_create(name, uevent_ops, parent_kobj);
879 if (!kset)
880 return NULL;
881 error = kset_register(kset);
882 if (error) {
883 kfree(kset);
884 return NULL;
885 }
886 return kset;
887}
888EXPORT_SYMBOL_GPL(kset_create_and_add);
889
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890EXPORT_SYMBOL(kobject_init);
891EXPORT_SYMBOL(kobject_register);
892EXPORT_SYMBOL(kobject_unregister);
893EXPORT_SYMBOL(kobject_get);
894EXPORT_SYMBOL(kobject_put);
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895EXPORT_SYMBOL(kobject_del);
896
897EXPORT_SYMBOL(kset_register);
898EXPORT_SYMBOL(kset_unregister);