blob: 99f6354a57511ddfd4c805cdaa3803a3bfdb8bd2 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * kobject.c - library routines for handling generic kernel objects
3 *
4 * Copyright (c) 2002-2003 Patrick Mochel <mochel@osdl.org>
Greg Kroah-Hartmanf0e7e1b2007-09-27 14:48:53 -07005 * Copyright (c) 2006-2007 Greg Kroah-Hartman <greg@kroah.com>
6 * Copyright (c) 2006-2007 Novell Inc.
Linus Torvalds1da177e2005-04-16 15:20:36 -07007 *
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>
Tim Schmielau4e57b682005-10-30 15:03:48 -080019#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020
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
Eric W. Biederman90bc6132007-07-31 19:15:08 +090049static int create_dir(struct kobject * kobj)
Linus Torvalds1da177e2005-04-16 15:20:36 -070050{
51 int error = 0;
52 if (kobject_name(kobj)) {
Eric W. Biederman90bc6132007-07-31 19:15:08 +090053 error = sysfs_create_dir(kobj);
Linus Torvalds1da177e2005-04-16 15:20:36 -070054 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 {
Chuck Ebbertb365b3d2006-01-12 20:02:00 -050077 if (kobject_name(parent) == NULL)
78 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070079 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
98 pr_debug("%s: path = '%s'\n",__FUNCTION__,path);
99}
100
101/**
Robert P. J. Day72fd4a32007-02-10 01:45:59 -0800102 * kobject_get_path - generate and return the path associated with a given kobj and kset pair.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103 *
104 * @kobj: kobject in question, with which to build the path
105 * @gfp_mask: the allocation type used to allocate the path
Robert P. J. Day72fd4a32007-02-10 01:45:59 -0800106 *
107 * The result must be freed by the caller with kfree().
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108 */
Al Virofd4f2df2005-10-21 03:18:50 -0400109char *kobject_get_path(struct kobject *kobj, gfp_t gfp_mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110{
111 char *path;
112 int len;
113
114 len = get_kobj_path_length(kobj);
Chuck Ebbertb365b3d2006-01-12 20:02:00 -0500115 if (len == 0)
116 return NULL;
Burman Yan4668edc2006-12-06 20:38:51 -0800117 path = kzalloc(len, gfp_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118 if (!path)
119 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120 fill_kobj_path(kobj, path, len);
121
122 return path;
123}
Dmitry Torokhov80fc9f52006-10-11 01:43:58 -0400124EXPORT_SYMBOL_GPL(kobject_get_path);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125
126/**
127 * kobject_init - initialize object.
128 * @kobj: object in question.
129 */
130void kobject_init(struct kobject * kobj)
131{
Greg Kroah-Hartman31b9025a2007-01-18 12:23:51 -0800132 if (!kobj)
133 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134 kref_init(&kobj->kref);
135 INIT_LIST_HEAD(&kobj->entry);
136 kobj->kset = kset_get(kobj->kset);
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
147 * kobject_del() and kobject_add() on error.
148 */
149
150static void unlink(struct kobject * kobj)
151{
152 if (kobj->kset) {
153 spin_lock(&kobj->kset->list_lock);
154 list_del_init(&kobj->entry);
155 spin_unlock(&kobj->kset->list_lock);
156 }
157 kobject_put(kobj);
158}
159
160/**
Eric W. Biederman90bc6132007-07-31 19:15:08 +0900161 * kobject_add - add an object to the hierarchy.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162 * @kobj: object.
163 */
164
Eric W. Biederman90bc6132007-07-31 19:15:08 +0900165int kobject_add(struct kobject * kobj)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166{
167 int error = 0;
168 struct kobject * parent;
169
170 if (!(kobj = kobject_get(kobj)))
171 return -ENOENT;
172 if (!kobj->k_name)
Greg Kroah-Hartmance2c9cb2007-09-12 15:06:57 -0700173 kobject_set_name(kobj, "NO_NAME");
Martin Stoilov13507702007-02-05 16:15:23 -0800174 if (!*kobj->k_name) {
Greg Kroah-Hartmanc171fef2006-01-20 14:08:59 -0800175 pr_debug("kobject attempted to be registered with no name!\n");
176 WARN_ON(1);
Cornelia Huck88db4722007-04-10 14:35:27 +0200177 kobject_put(kobj);
Greg Kroah-Hartmanc171fef2006-01-20 14:08:59 -0800178 return -EINVAL;
179 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180 parent = kobject_get(kobj->parent);
181
182 pr_debug("kobject %s: registering. parent: %s, set: %s\n",
183 kobject_name(kobj), parent ? kobject_name(parent) : "<NULL>",
Greg Kroah-Hartmance2c9cb2007-09-12 15:06:57 -0700184 kobj->kset ? kobject_name(&kobj->kset->kobj) : "<NULL>" );
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185
186 if (kobj->kset) {
187 spin_lock(&kobj->kset->list_lock);
188
Greg Kroah-Hartmanb727c702007-09-27 14:48:53 -0700189 if (!parent) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190 parent = kobject_get(&kobj->kset->kobj);
Greg Kroah-Hartmanb727c702007-09-27 14:48:53 -0700191 /*
192 * If the kset is our parent, get a second
193 * reference, we drop both the kset and the
194 * parent ref on cleanup
195 */
196 kobject_get(parent);
197 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198
199 list_add_tail(&kobj->entry,&kobj->kset->list);
200 spin_unlock(&kobj->kset->list_lock);
Dmitriy Monakhov460f7e92007-03-10 14:00:10 +0300201 kobj->parent = parent;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700203
Eric W. Biederman90bc6132007-07-31 19:15:08 +0900204 error = create_dir(kobj);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700205 if (error) {
206 /* unlink does the kobject_put() for us */
207 unlink(kobj);
Mariusz Kozlowskib067db42007-01-02 13:44:44 +0100208 kobject_put(parent);
Greg Kroah-Hartmandcd0da02006-03-20 13:17:13 -0800209
210 /* be noisy on error issues */
211 if (error == -EEXIST)
Greg Kroah-Hartman5c73a3f2007-06-07 15:05:15 -0700212 printk(KERN_ERR "kobject_add failed for %s with "
213 "-EEXIST, don't try to register things with "
214 "the same name in the same directory.\n",
Greg Kroah-Hartmandcd0da02006-03-20 13:17:13 -0800215 kobject_name(kobj));
216 else
Greg Kroah-Hartman5c73a3f2007-06-07 15:05:15 -0700217 printk(KERN_ERR "kobject_add failed for %s (%d)\n",
Greg Kroah-Hartmandcd0da02006-03-20 13:17:13 -0800218 kobject_name(kobj), error);
Greg Kroah-Hartman5c73a3f2007-06-07 15:05:15 -0700219 dump_stack();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700220 }
221
222 return error;
223}
224
Eric W. Biedermanb592fcf2007-01-24 12:35:52 -0700225/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226 * kobject_register - initialize and add an object.
227 * @kobj: object in question.
228 */
229
230int kobject_register(struct kobject * kobj)
231{
Greg Kroah-Hartmandcd0da02006-03-20 13:17:13 -0800232 int error = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233 if (kobj) {
234 kobject_init(kobj);
235 error = kobject_add(kobj);
Greg Kroah-Hartmandcd0da02006-03-20 13:17:13 -0800236 if (!error)
Kay Sievers312c0042005-11-16 09:00:00 +0100237 kobject_uevent(kobj, KOBJ_ADD);
Greg Kroah-Hartmandcd0da02006-03-20 13:17:13 -0800238 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239 return error;
240}
241
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242/**
Greg Kroah-Hartman663a4742007-11-29 18:32:47 -0500243 * kobject_set_name_vargs - Set the name of an kobject
244 * @kobj: struct kobject to set the name of
Greg Kroah-Hartman8c4606b2007-12-04 14:45:47 +0800245 * @fmt: format string used to build the name
Greg Kroah-Hartman663a4742007-11-29 18:32:47 -0500246 * @vargs: vargs to format the string.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247 */
Greg Kroah-Hartman663a4742007-11-29 18:32:47 -0500248static int kobject_set_name_vargs(struct kobject *kobj, const char *fmt,
249 va_list vargs)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250{
Greg Kroah-Hartman663a4742007-11-29 18:32:47 -0500251 va_list aq;
Greg Kroah-Hartmance2c9cb2007-09-12 15:06:57 -0700252 char *name;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253
Greg Kroah-Hartman663a4742007-11-29 18:32:47 -0500254 va_copy(aq, vargs);
255 name = kvasprintf(GFP_KERNEL, fmt, vargs);
256 va_end(aq);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257
Greg Kroah-Hartman663a4742007-11-29 18:32:47 -0500258 if (!name)
259 return -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700260
261 /* Free the old name, if necessary. */
Greg Kroah-Hartmance2c9cb2007-09-12 15:06:57 -0700262 kfree(kobj->k_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700263
264 /* Now, set the new name */
265 kobj->k_name = name;
Greg Kroah-Hartman663a4742007-11-29 18:32:47 -0500266
267 return 0;
268}
269
270/**
271 * kobject_set_name - Set the name of a kobject
272 * @kobj: struct kobject to set the name of
273 * @fmt: format string used to build the name
274 *
275 * This sets the name of the kobject. If you have already added the
276 * kobject to the system, you must call kobject_rename() in order to
277 * change the name of the kobject.
278 */
279int kobject_set_name(struct kobject *kobj, const char *fmt, ...)
280{
281 va_list args;
282 int retval;
283
284 va_start(args, fmt);
285 retval = kobject_set_name_vargs(kobj, fmt, args);
286 va_end(args);
287
288 return retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290EXPORT_SYMBOL(kobject_set_name);
291
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292/**
Greg Kroah-Hartmane86000d2007-12-03 21:31:08 -0800293 * kobject_init_ng - initialize a kobject structure
294 * @kobj: pointer to the kobject to initialize
295 * @ktype: pointer to the ktype for this kobject.
296 *
297 * This function will properly initialize a kobject such that it can then
298 * be passed to the kobject_add() call.
299 *
300 * After this function is called, the kobject MUST be cleaned up by a call
301 * to kobject_put(), not by a call to kfree directly to ensure that all of
302 * the memory is cleaned up properly.
303 */
304void kobject_init_ng(struct kobject *kobj, struct kobj_type *ktype)
305{
306 char *err_str;
307
308 if (!kobj) {
309 err_str = "invalid kobject pointer!";
310 goto error;
311 }
312 if (!ktype) {
313 err_str = "must have a ktype to be initialized properly!\n";
314 goto error;
315 }
316 if (atomic_read(&kobj->kref.refcount)) {
317 /* do not error out as sometimes we can recover */
318 printk(KERN_ERR "kobject: reference count is already set, "
319 "something is seriously wrong.\n");
320 dump_stack();
321 }
322
323 kref_init(&kobj->kref);
324 INIT_LIST_HEAD(&kobj->entry);
325 kobj->ktype = ktype;
326 return;
327
328error:
329 printk(KERN_ERR "kobject: %s\n", err_str);
330 dump_stack();
331}
332EXPORT_SYMBOL(kobject_init_ng);
333
Greg Kroah-Hartman244f6ce2007-12-03 21:31:08 -0800334static int kobject_add_varg(struct kobject *kobj, struct kobject *parent,
335 const char *fmt, va_list vargs)
336{
337 va_list aq;
338 int retval;
339
340 va_copy(aq, vargs);
341 retval = kobject_set_name_vargs(kobj, fmt, aq);
342 va_end(aq);
343 if (retval) {
344 printk(KERN_ERR "kobject: can not set name properly!\n");
345 return retval;
346 }
347 kobj->parent = parent;
348 return kobject_add(kobj);
349}
350
351/**
352 * kobject_add_ng - the main kobject add function
353 * @kobj: the kobject to add
354 * @parent: pointer to the parent of the kobject.
355 * @fmt: format to name the kobject with.
356 *
357 * The kobject name is set and added to the kobject hierarchy in this
358 * function.
359 *
360 * If @parent is set, then the parent of the @kobj will be set to it.
361 * If @parent is NULL, then the parent of the @kobj will be set to the
362 * kobject associted with the kset assigned to this kobject. If no kset
363 * is assigned to the kobject, then the kobject will be located in the
364 * root of the sysfs tree.
365 *
366 * If this function returns an error, kobject_put() must be called to
367 * properly clean up the memory associated with the object.
368 *
369 * If the function is successful, the only way to properly clean up the
370 * memory is with a call to kobject_del(), in which case, a call to
371 * kobject_put() is not necessary (kobject_del() does the final
372 * kobject_put() to call the release function in the ktype's release
373 * pointer.)
374 *
375 * Under no instance should the kobject that is passed to this function
376 * be directly freed with a call to kfree(), that can leak memory.
377 *
378 * Note, no uevent will be created with this call, the caller should set
379 * up all of the necessary sysfs files for the object and then call
380 * kobject_uevent() with the UEVENT_ADD parameter to ensure that
381 * userspace is properly notified of this kobject's creation.
382 */
383int kobject_add_ng(struct kobject *kobj, struct kobject *parent,
384 const char *fmt, ...)
385{
386 va_list args;
387 int retval;
388
389 if (!kobj)
390 return -EINVAL;
391
392 va_start(args, fmt);
393 retval = kobject_add_varg(kobj, parent, fmt, args);
394 va_end(args);
395
396 return retval;
397}
398EXPORT_SYMBOL(kobject_add_ng);
399
Greg Kroah-Hartmane86000d2007-12-03 21:31:08 -0800400/**
Greg Kroah-Hartmanc11c4152007-12-03 21:31:08 -0800401 * kobject_init_and_add - initialize a kobject structure and add it to the kobject hierarchy
402 * @kobj: pointer to the kobject to initialize
403 * @ktype: pointer to the ktype for this kobject.
404 * @parent: pointer to the parent of this kobject.
405 * @fmt: the name of the kobject.
406 *
407 * This function combines the call to kobject_init_ng() and
408 * kobject_add_ng(). The same type of error handling after a call to
409 * kobject_add_ng() and kobject lifetime rules are the same here.
410 */
411int kobject_init_and_add(struct kobject *kobj, struct kobj_type *ktype,
412 struct kobject *parent, const char *fmt, ...)
413{
414 va_list args;
415 int retval;
416
417 kobject_init_ng(kobj, ktype);
418
419 va_start(args, fmt);
420 retval = kobject_add_varg(kobj, parent, fmt, args);
421 va_end(args);
422
423 return retval;
424}
425EXPORT_SYMBOL_GPL(kobject_init_and_add);
426
427/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700428 * kobject_rename - change the name of an object
429 * @kobj: object in question.
430 * @new_name: object's new name
431 */
432
Dmitry Torokhovf3b4f3c2005-04-26 02:32:00 -0500433int kobject_rename(struct kobject * kobj, const char *new_name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434{
435 int error = 0;
Jean Tourrilhesca2f37d2007-03-07 10:49:30 -0800436 const char *devpath = NULL;
437 char *devpath_string = NULL;
438 char *envp[2];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439
440 kobj = kobject_get(kobj);
441 if (!kobj)
442 return -EINVAL;
Eric W. Biedermanb592fcf2007-01-24 12:35:52 -0700443 if (!kobj->parent)
444 return -EINVAL;
Jean Tourrilhesca2f37d2007-03-07 10:49:30 -0800445
Greg Kroah-Hartman34358c22007-10-24 16:52:31 -0700446 /* see if this name is already in use */
447 if (kobj->kset) {
448 struct kobject *temp_kobj;
449 temp_kobj = kset_find_obj(kobj->kset, new_name);
450 if (temp_kobj) {
Johannes Berg71409a42007-11-05 13:59:11 +0100451 printk(KERN_WARNING "kobject '%s' cannot be renamed "
452 "to '%s' as '%s' is already in existence.\n",
Greg Kroah-Hartman34358c22007-10-24 16:52:31 -0700453 kobject_name(kobj), new_name, new_name);
454 kobject_put(temp_kobj);
455 return -EINVAL;
456 }
457 }
458
Jean Tourrilhesca2f37d2007-03-07 10:49:30 -0800459 devpath = kobject_get_path(kobj, GFP_KERNEL);
460 if (!devpath) {
461 error = -ENOMEM;
462 goto out;
463 }
464 devpath_string = kmalloc(strlen(devpath) + 15, GFP_KERNEL);
465 if (!devpath_string) {
466 error = -ENOMEM;
467 goto out;
468 }
469 sprintf(devpath_string, "DEVPATH_OLD=%s", devpath);
470 envp[0] = devpath_string;
471 envp[1] = NULL;
Jean Tourrilhesca2f37d2007-03-07 10:49:30 -0800472
Eric W. Biederman90bc6132007-07-31 19:15:08 +0900473 error = sysfs_rename_dir(kobj, new_name);
Jean Tourrilhesca2f37d2007-03-07 10:49:30 -0800474
475 /* This function is mostly/only used for network interface.
476 * Some hotplug package track interfaces by their name and
477 * therefore want to know when the name is changed by the user. */
478 if (!error)
479 kobject_uevent_env(kobj, KOBJ_MOVE, envp);
480
481out:
482 kfree(devpath_string);
483 kfree(devpath);
Eric W. Biedermanb592fcf2007-01-24 12:35:52 -0700484 kobject_put(kobj);
485
486 return error;
487}
488
489/**
Cornelia Huck8a824722006-11-20 17:07:51 +0100490 * kobject_move - move object to another parent
491 * @kobj: object in question.
Cornelia Huckc744aeae2007-01-08 20:16:44 +0100492 * @new_parent: object's new parent (can be NULL)
Cornelia Huck8a824722006-11-20 17:07:51 +0100493 */
494
495int kobject_move(struct kobject *kobj, struct kobject *new_parent)
496{
497 int error;
498 struct kobject *old_parent;
499 const char *devpath = NULL;
500 char *devpath_string = NULL;
501 char *envp[2];
502
503 kobj = kobject_get(kobj);
504 if (!kobj)
505 return -EINVAL;
506 new_parent = kobject_get(new_parent);
507 if (!new_parent) {
Cornelia Huckc744aeae2007-01-08 20:16:44 +0100508 if (kobj->kset)
509 new_parent = kobject_get(&kobj->kset->kobj);
Cornelia Huck8a824722006-11-20 17:07:51 +0100510 }
511 /* old object path */
512 devpath = kobject_get_path(kobj, GFP_KERNEL);
513 if (!devpath) {
514 error = -ENOMEM;
515 goto out;
516 }
517 devpath_string = kmalloc(strlen(devpath) + 15, GFP_KERNEL);
518 if (!devpath_string) {
519 error = -ENOMEM;
520 goto out;
521 }
522 sprintf(devpath_string, "DEVPATH_OLD=%s", devpath);
523 envp[0] = devpath_string;
524 envp[1] = NULL;
525 error = sysfs_move_dir(kobj, new_parent);
526 if (error)
527 goto out;
528 old_parent = kobj->parent;
529 kobj->parent = new_parent;
Dmitriy Monakhov9e993ef2007-03-03 16:11:21 +0300530 new_parent = NULL;
Cornelia Huck8a824722006-11-20 17:07:51 +0100531 kobject_put(old_parent);
532 kobject_uevent_env(kobj, KOBJ_MOVE, envp);
533out:
Dmitriy Monakhov9e993ef2007-03-03 16:11:21 +0300534 kobject_put(new_parent);
Cornelia Huck8a824722006-11-20 17:07:51 +0100535 kobject_put(kobj);
536 kfree(devpath_string);
537 kfree(devpath);
538 return error;
539}
540
541/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542 * kobject_del - unlink kobject from hierarchy.
543 * @kobj: object.
544 */
545
546void kobject_del(struct kobject * kobj)
547{
Greg Kroah-Hartman31b9025a2007-01-18 12:23:51 -0800548 if (!kobj)
549 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700550 sysfs_remove_dir(kobj);
551 unlink(kobj);
552}
553
554/**
555 * kobject_unregister - remove object from hierarchy and decrement refcount.
556 * @kobj: object going away.
557 */
558
559void kobject_unregister(struct kobject * kobj)
560{
Greg Kroah-Hartman31b9025a2007-01-18 12:23:51 -0800561 if (!kobj)
562 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700563 pr_debug("kobject %s: unregistering\n",kobject_name(kobj));
Kay Sievers312c0042005-11-16 09:00:00 +0100564 kobject_uevent(kobj, KOBJ_REMOVE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565 kobject_del(kobj);
566 kobject_put(kobj);
567}
568
569/**
570 * kobject_get - increment refcount for object.
571 * @kobj: object.
572 */
573
574struct kobject * kobject_get(struct kobject * kobj)
575{
576 if (kobj)
577 kref_get(&kobj->kref);
578 return kobj;
579}
580
Greg Kroah-Hartman18041f42007-12-03 21:31:08 -0800581/*
582 * kobject_cleanup - free kobject resources.
583 * @kobj: object to cleanup
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584 */
Greg Kroah-Hartman18041f42007-12-03 21:31:08 -0800585static void kobject_cleanup(struct kobject *kobj)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700586{
587 struct kobj_type * t = get_ktype(kobj);
588 struct kset * s = kobj->kset;
589 struct kobject * parent = kobj->parent;
Greg Kroah-Hartmance2c9cb2007-09-12 15:06:57 -0700590 const char *name = kobj->k_name;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591
592 pr_debug("kobject %s: cleaning up\n",kobject_name(kobj));
Greg Kroah-Hartmance2c9cb2007-09-12 15:06:57 -0700593 if (t && t->release) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700594 t->release(kobj);
Greg Kroah-Hartmance2c9cb2007-09-12 15:06:57 -0700595 /* If we have a release function, we can guess that this was
596 * not a statically allocated kobject, so we should be safe to
597 * free the name */
598 kfree(name);
599 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700600 if (s)
601 kset_put(s);
Mariusz Kozlowskib067db42007-01-02 13:44:44 +0100602 kobject_put(parent);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700603}
604
605static void kobject_release(struct kref *kref)
606{
607 kobject_cleanup(container_of(kref, struct kobject, kref));
608}
609
610/**
611 * kobject_put - decrement refcount for object.
612 * @kobj: object.
613 *
614 * Decrement the refcount, and if 0, call kobject_cleanup().
615 */
616void kobject_put(struct kobject * kobj)
617{
618 if (kobj)
619 kref_put(&kobj->kref, kobject_release);
620}
621
Greg Kroah-Hartman3f9e3ee2007-11-05 13:16:15 -0800622static void dynamic_kobj_release(struct kobject *kobj)
Jun'ichi Nomura74231722006-03-13 17:14:25 -0500623{
Greg Kroah-Hartman3f9e3ee2007-11-05 13:16:15 -0800624 pr_debug("%s: freeing %s\n", __FUNCTION__, kobject_name(kobj));
Jun'ichi Nomura74231722006-03-13 17:14:25 -0500625 kfree(kobj);
626}
627
Greg Kroah-Hartman3f9e3ee2007-11-05 13:16:15 -0800628static struct kobj_type dynamic_kobj_ktype = {
Kay Sievers386f2752007-11-02 13:47:53 +0100629 .release = dynamic_kobj_release,
630 .sysfs_ops = &kobj_sysfs_ops,
Jun'ichi Nomura74231722006-03-13 17:14:25 -0500631};
632
Greg Kroah-Hartman43968d22007-11-05 22:24:43 -0800633/**
Greg Kroah-Hartman3f9e3ee2007-11-05 13:16:15 -0800634 * kobject_create - create a struct kobject dynamically
635 *
636 * This function creates a kobject structure dynamically and sets it up
637 * to be a "dynamic" kobject with a default release function set up.
638 *
639 * If the kobject was not able to be created, NULL will be returned.
Greg Kroah-Hartman43968d22007-11-05 22:24:43 -0800640 * The kobject structure returned from here must be cleaned up with a
641 * call to kobject_put() and not kfree(), as kobject_init_ng() has
642 * already been called on this structure.
Greg Kroah-Hartman3f9e3ee2007-11-05 13:16:15 -0800643 */
Greg Kroah-Hartman43968d22007-11-05 22:24:43 -0800644struct kobject *kobject_create(void)
Greg Kroah-Hartman3f9e3ee2007-11-05 13:16:15 -0800645{
646 struct kobject *kobj;
647
648 kobj = kzalloc(sizeof(*kobj), GFP_KERNEL);
649 if (!kobj)
650 return NULL;
651
652 kobject_init_ng(kobj, &dynamic_kobj_ktype);
653 return kobj;
654}
655
656/**
657 * kobject_create_and_add - create a struct kobject dynamically and register it with sysfs
658 *
659 * @name: the name for the kset
660 * @parent: the parent kobject of this kobject, if any.
661 *
662 * This function creates a kset structure dynamically and registers it
663 * with sysfs. When you are finished with this structure, call
664 * kobject_unregister() and the structure will be dynamically freed when
665 * it is no longer being used.
666 *
667 * If the kobject was not able to be created, NULL will be returned.
668 */
669struct kobject *kobject_create_and_add(const char *name, struct kobject *parent)
670{
671 struct kobject *kobj;
672 int retval;
673
674 kobj = kobject_create();
675 if (!kobj)
676 return NULL;
677
678 retval = kobject_add_ng(kobj, parent, "%s", name);
679 if (retval) {
680 printk(KERN_WARNING "%s: kobject_add error: %d\n",
681 __FUNCTION__, retval);
682 kobject_put(kobj);
683 kobj = NULL;
684 }
685 return kobj;
686}
687EXPORT_SYMBOL_GPL(kobject_create_and_add);
688
Jun'ichi Nomura74231722006-03-13 17:14:25 -0500689/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700690 * kset_init - initialize a kset for use
691 * @k: kset
692 */
693
694void kset_init(struct kset * k)
695{
696 kobject_init(&k->kobj);
697 INIT_LIST_HEAD(&k->list);
698 spin_lock_init(&k->list_lock);
699}
700
Kay Sievers23b52122007-11-02 13:47:53 +0100701/* default kobject attribute operations */
702static ssize_t kobj_attr_show(struct kobject *kobj, struct attribute *attr,
703 char *buf)
704{
705 struct kobj_attribute *kattr;
706 ssize_t ret = -EIO;
707
708 kattr = container_of(attr, struct kobj_attribute, attr);
709 if (kattr->show)
710 ret = kattr->show(kobj, kattr, buf);
711 return ret;
712}
713
714static ssize_t kobj_attr_store(struct kobject *kobj, struct attribute *attr,
715 const char *buf, size_t count)
716{
717 struct kobj_attribute *kattr;
718 ssize_t ret = -EIO;
719
720 kattr = container_of(attr, struct kobj_attribute, attr);
721 if (kattr->store)
722 ret = kattr->store(kobj, kattr, buf, count);
723 return ret;
724}
725
726struct sysfs_ops kobj_sysfs_ops = {
727 .show = kobj_attr_show,
728 .store = kobj_attr_store,
729};
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730
731/**
732 * kset_add - add a kset object to the hierarchy.
733 * @k: kset.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734 */
735
736int kset_add(struct kset * k)
737{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738 return kobject_add(&k->kobj);
739}
740
741
742/**
743 * kset_register - initialize and add a kset.
744 * @k: kset.
745 */
746
747int kset_register(struct kset * k)
748{
Kay Sievers80f03e32007-05-26 11:21:36 +0200749 int err;
750
Greg Kroah-Hartman31b9025a2007-01-18 12:23:51 -0800751 if (!k)
752 return -EINVAL;
Kay Sievers80f03e32007-05-26 11:21:36 +0200753
Linus Torvalds1da177e2005-04-16 15:20:36 -0700754 kset_init(k);
Kay Sievers80f03e32007-05-26 11:21:36 +0200755 err = kset_add(k);
756 if (err)
757 return err;
758 kobject_uevent(&k->kobj, KOBJ_ADD);
759 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700760}
761
762
763/**
764 * kset_unregister - remove a kset.
765 * @k: kset.
766 */
767
768void kset_unregister(struct kset * k)
769{
Greg Kroah-Hartman31b9025a2007-01-18 12:23:51 -0800770 if (!k)
771 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700772 kobject_unregister(&k->kobj);
773}
774
775
776/**
777 * kset_find_obj - search for object in kset.
778 * @kset: kset we're looking in.
779 * @name: object's name.
780 *
781 * Lock kset via @kset->subsys, and iterate over @kset->list,
782 * looking for a matching kobject. If matching object is found
783 * take a reference and return the object.
784 */
785
786struct kobject * kset_find_obj(struct kset * kset, const char * name)
787{
788 struct list_head * entry;
789 struct kobject * ret = NULL;
790
791 spin_lock(&kset->list_lock);
792 list_for_each(entry,&kset->list) {
793 struct kobject * k = to_kobj(entry);
794 if (kobject_name(k) && !strcmp(kobject_name(k),name)) {
795 ret = kobject_get(k);
796 break;
797 }
798 }
799 spin_unlock(&kset->list_lock);
800 return ret;
801}
802
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -0700803int subsystem_register(struct kset *s)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700804{
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -0700805 return kset_register(s);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700806}
807
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -0700808void subsystem_unregister(struct kset *s)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700809{
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -0700810 kset_unregister(s);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700811}
812
Linus Torvalds1da177e2005-04-16 15:20:36 -0700813/**
814 * subsystem_create_file - export sysfs attribute file.
815 * @s: subsystem.
816 * @a: subsystem attribute descriptor.
817 */
818
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -0700819int subsys_create_file(struct kset *s, struct subsys_attribute *a)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700820{
821 int error = 0;
Greg Kroah-Hartman31b9025a2007-01-18 12:23:51 -0800822
823 if (!s || !a)
824 return -EINVAL;
825
Greg Kroah-Hartman1ef4cfa2007-09-12 15:06:57 -0700826 if (kset_get(s)) {
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -0700827 error = sysfs_create_file(&s->kobj, &a->attr);
Greg Kroah-Hartman6e9d9302007-09-12 15:06:57 -0700828 kset_put(s);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700829 }
830 return error;
831}
832
Greg Kroah-Hartmanb727c702007-09-27 14:48:53 -0700833static void kset_release(struct kobject *kobj)
834{
835 struct kset *kset = container_of(kobj, struct kset, kobj);
836 pr_debug("kset %s: now freed\n", kobject_name(kobj));
837 kfree(kset);
838}
839
Kay Sievers386f2752007-11-02 13:47:53 +0100840static struct kobj_type kset_ktype = {
841 .sysfs_ops = &kobj_sysfs_ops,
Greg Kroah-Hartmanb727c702007-09-27 14:48:53 -0700842 .release = kset_release,
843};
844
845/**
846 * kset_create - create a struct kset dynamically
847 *
848 * @name: the name for the kset
849 * @uevent_ops: a struct kset_uevent_ops for the kset
850 * @parent_kobj: the parent kobject of this kset, if any.
851 *
852 * This function creates a kset structure dynamically. This structure can
853 * then be registered with the system and show up in sysfs with a call to
854 * kset_register(). When you are finished with this structure, if
855 * kset_register() has been called, call kset_unregister() and the
856 * structure will be dynamically freed when it is no longer being used.
857 *
858 * If the kset was not able to be created, NULL will be returned.
859 */
860static struct kset *kset_create(const char *name,
861 struct kset_uevent_ops *uevent_ops,
862 struct kobject *parent_kobj)
863{
864 struct kset *kset;
865
866 kset = kzalloc(sizeof(*kset), GFP_KERNEL);
867 if (!kset)
868 return NULL;
869 kobject_set_name(&kset->kobj, name);
870 kset->uevent_ops = uevent_ops;
871 kset->kobj.parent = parent_kobj;
872
873 /*
Kay Sievers386f2752007-11-02 13:47:53 +0100874 * The kobject of this kset will have a type of kset_ktype and belong to
Greg Kroah-Hartmanb727c702007-09-27 14:48:53 -0700875 * no kset itself. That way we can properly free it when it is
876 * finished being used.
877 */
Kay Sievers386f2752007-11-02 13:47:53 +0100878 kset->kobj.ktype = &kset_ktype;
Greg Kroah-Hartmanb727c702007-09-27 14:48:53 -0700879 kset->kobj.kset = NULL;
880
881 return kset;
882}
883
884/**
885 * kset_create_and_add - create a struct kset dynamically and add it to sysfs
886 *
887 * @name: the name for the kset
888 * @uevent_ops: a struct kset_uevent_ops for the kset
889 * @parent_kobj: the parent kobject of this kset, if any.
890 *
891 * This function creates a kset structure dynamically and registers it
892 * with sysfs. When you are finished with this structure, call
893 * kset_unregister() and the structure will be dynamically freed when it
894 * is no longer being used.
895 *
896 * If the kset was not able to be created, NULL will be returned.
897 */
898struct kset *kset_create_and_add(const char *name,
899 struct kset_uevent_ops *uevent_ops,
900 struct kobject *parent_kobj)
901{
902 struct kset *kset;
903 int error;
904
905 kset = kset_create(name, uevent_ops, parent_kobj);
906 if (!kset)
907 return NULL;
908 error = kset_register(kset);
909 if (error) {
910 kfree(kset);
911 return NULL;
912 }
913 return kset;
914}
915EXPORT_SYMBOL_GPL(kset_create_and_add);
916
Linus Torvalds1da177e2005-04-16 15:20:36 -0700917EXPORT_SYMBOL(kobject_init);
918EXPORT_SYMBOL(kobject_register);
919EXPORT_SYMBOL(kobject_unregister);
920EXPORT_SYMBOL(kobject_get);
921EXPORT_SYMBOL(kobject_put);
922EXPORT_SYMBOL(kobject_add);
923EXPORT_SYMBOL(kobject_del);
924
925EXPORT_SYMBOL(kset_register);
926EXPORT_SYMBOL(kset_unregister);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700927
Linus Torvalds1da177e2005-04-16 15:20:36 -0700928EXPORT_SYMBOL(subsystem_register);
929EXPORT_SYMBOL(subsystem_unregister);
930EXPORT_SYMBOL(subsys_create_file);