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1 | /* | |
2 | * kobject.c - library routines for handling generic kernel objects | |
3 | * | |
4 | * Copyright (c) 2002-2003 Patrick Mochel <mochel@osdl.org> | |
5 | * Copyright (c) 2006-2007 Greg Kroah-Hartman <greg@kroah.com> | |
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 | */ | |
30 | const 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 | */ | |
49 | static 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 | ||
66 | static 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 | ||
103 | static 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 | ||
121 | static 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 | */ | |
146 | char *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 | } | |
161 | EXPORT_SYMBOL_GPL(kobject_get_path); | |
162 | ||
163 | /* add the kobject to its kset's list */ | |
164 | static 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 */ | |
176 | static 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 | ||
187 | static 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 | ||
200 | static 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 | */ | |
257 | int 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 | */ | |
289 | int 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 | } | |
300 | EXPORT_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 | */ | |
314 | void 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 | ||
337 | error: | |
338 | printk(KERN_ERR "kobject (%p): %s\n", kobj, err_str); | |
339 | dump_stack(); | |
340 | } | |
341 | EXPORT_SYMBOL(kobject_init); | |
342 | ||
343 | static 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 | */ | |
382 | int 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 | } | |
404 | EXPORT_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 | */ | |
417 | int 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 | } | |
431 | EXPORT_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 | */ | |
443 | int 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 | ||
490 | out: | |
491 | kfree(dup_name); | |
492 | kfree(devpath_string); | |
493 | kfree(devpath); | |
494 | kobject_put(kobj); | |
495 | ||
496 | return error; | |
497 | } | |
498 | EXPORT_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 | */ | |
505 | int 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); | |
544 | out: | |
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 | */ | |
556 | void 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 | */ | |
577 | struct kobject *kobject_get(struct kobject *kobj) | |
578 | { | |
579 | if (kobj) | |
580 | kref_get(&kobj->kref); | |
581 | return kobj; | |
582 | } | |
583 | ||
584 | static 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 | */ | |
595 | static 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 | |
636 | static 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 | ||
643 | static 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 | */ | |
664 | void 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 | ||
675 | static void dynamic_kobj_release(struct kobject *kobj) | |
676 | { | |
677 | pr_debug("kobject: (%p): %s\n", kobj, __func__); | |
678 | kfree(kobj); | |
679 | } | |
680 | ||
681 | static 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 | */ | |
697 | struct 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 | */ | |
722 | struct 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 | } | |
740 | EXPORT_SYMBOL_GPL(kobject_create_and_add); | |
741 | ||
742 | /** | |
743 | * kset_init - initialize a kset for use | |
744 | * @k: kset | |
745 | */ | |
746 | void 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 */ | |
754 | static 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 | ||
766 | static 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 | ||
778 | const struct sysfs_ops kobj_sysfs_ops = { | |
779 | .show = kobj_attr_show, | |
780 | .store = kobj_attr_store, | |
781 | }; | |
782 | EXPORT_SYMBOL_GPL(kobj_sysfs_ops); | |
783 | ||
784 | /** | |
785 | * kset_register - initialize and add a kset. | |
786 | * @k: kset. | |
787 | */ | |
788 | int 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 | */ | |
807 | void 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 | */ | |
824 | struct 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 | ||
842 | static 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 | ||
850 | static 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 | */ | |
870 | static 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 | */ | |
913 | struct 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 | } | |
930 | EXPORT_SYMBOL_GPL(kset_create_and_add); | |
931 | ||
932 | ||
933 | static DEFINE_SPINLOCK(kobj_ns_type_lock); | |
934 | static const struct kobj_ns_type_operations *kobj_ns_ops_tbl[KOBJ_NS_TYPES]; | |
935 | ||
936 | int 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 | ||
958 | out: | |
959 | spin_unlock(&kobj_ns_type_lock); | |
960 | return error; | |
961 | } | |
962 | ||
963 | int 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 | ||
975 | const 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 | ||
985 | const struct kobj_ns_type_operations *kobj_ns_ops(struct kobject *kobj) | |
986 | { | |
987 | return kobj_child_ns_ops(kobj->parent); | |
988 | } | |
989 | ||
990 | bool 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 | ||
1003 | void *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 | ||
1016 | const 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 | ||
1029 | const 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 | ||
1042 | void 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 | ||
1051 | EXPORT_SYMBOL(kobject_get); | |
1052 | EXPORT_SYMBOL(kobject_put); | |
1053 | EXPORT_SYMBOL(kobject_del); | |
1054 | ||
1055 | EXPORT_SYMBOL(kset_register); | |
1056 | EXPORT_SYMBOL(kset_unregister); |