]> git.proxmox.com Git - mirror_ubuntu-jammy-kernel.git/blame - lib/kobject.c
KVM: x86/speculation: Disable Fill buffer clear within guests
[mirror_ubuntu-jammy-kernel.git] / lib / kobject.c
CommitLineData
d9d16e16 1// SPDX-License-Identifier: GPL-2.0
1da177e4
LT
2/*
3 * kobject.c - library routines for handling generic kernel objects
4 *
5 * Copyright (c) 2002-2003 Patrick Mochel <mochel@osdl.org>
f0e7e1bd
GKH
6 * Copyright (c) 2006-2007 Greg Kroah-Hartman <greg@kroah.com>
7 * Copyright (c) 2006-2007 Novell Inc.
1da177e4 8 *
0c1bc6b8 9 * Please see the file Documentation/core-api/kobject.rst for critical information
1da177e4
LT
10 * about using the kobject interface.
11 */
12
13#include <linux/kobject.h>
14#include <linux/string.h>
8bc3bcc9 15#include <linux/export.h>
1da177e4 16#include <linux/stat.h>
4e57b681 17#include <linux/slab.h>
89c86a64 18#include <linux/random.h>
1da177e4 19
e34ff490 20/**
ed856349 21 * kobject_namespace() - Return @kobj's namespace tag.
e34ff490
TH
22 * @kobj: kobject in question
23 *
24 * Returns namespace tag of @kobj if its parent has namespace ops enabled
25 * and thus @kobj should have a namespace tag associated with it. Returns
26 * %NULL otherwise.
27 */
28const void *kobject_namespace(struct kobject *kobj)
29{
30 const struct kobj_ns_type_operations *ns_ops = kobj_ns_ops(kobj);
31
32 if (!ns_ops || ns_ops->type == KOBJ_NS_TYPE_NONE)
33 return NULL;
34
a1212d27 35 return kobj->ktype->namespace(kobj);
e34ff490
TH
36}
37
5f81880d 38/**
ed856349 39 * kobject_get_ownership() - Get sysfs ownership data for @kobj.
5f81880d
DT
40 * @kobj: kobject in question
41 * @uid: kernel user ID for sysfs objects
42 * @gid: kernel group ID for sysfs objects
43 *
44 * Returns initial uid/gid pair that should be used when creating sysfs
45 * representation of given kobject. Normally used to adjust ownership of
46 * objects in a container.
47 */
48void kobject_get_ownership(struct kobject *kobj, kuid_t *uid, kgid_t *gid)
49{
50 *uid = GLOBAL_ROOT_UID;
51 *gid = GLOBAL_ROOT_GID;
52
53 if (kobj->ktype->get_ownership)
54 kobj->ktype->get_ownership(kobj, uid, gid);
55}
56
e374a2bf
GKH
57/*
58 * populate_dir - populate directory with attributes.
59 * @kobj: object we're working on.
1da177e4 60 *
e374a2bf
GKH
61 * Most subsystems have a set of default attributes that are associated
62 * with an object that registers with them. This is a helper called during
63 * object registration that loops through the default attributes of the
64 * subsystem and creates attributes files for them in sysfs.
1da177e4 65 */
e374a2bf 66static int populate_dir(struct kobject *kobj)
1da177e4 67{
e374a2bf
GKH
68 struct kobj_type *t = get_ktype(kobj);
69 struct attribute *attr;
1da177e4
LT
70 int error = 0;
71 int i;
e374a2bf 72
1da177e4
LT
73 if (t && t->default_attrs) {
74 for (i = 0; (attr = t->default_attrs[i]) != NULL; i++) {
e374a2bf
GKH
75 error = sysfs_create_file(kobj, attr);
76 if (error)
1da177e4
LT
77 break;
78 }
79 }
80 return error;
81}
82
e374a2bf 83static int create_dir(struct kobject *kobj)
1da177e4 84{
aa30f47c 85 const struct kobj_type *ktype = get_ktype(kobj);
c84a3b27 86 const struct kobj_ns_type_operations *ops;
e34ff490
TH
87 int error;
88
89 error = sysfs_create_dir_ns(kobj, kobject_namespace(kobj));
c84a3b27
TH
90 if (error)
91 return error;
92
93 error = populate_dir(kobj);
94 if (error) {
95 sysfs_remove_dir(kobj);
96 return error;
1da177e4 97 }
26ea12de 98
aa30f47c
KB
99 if (ktype) {
100 error = sysfs_create_groups(kobj, ktype->default_groups);
101 if (error) {
102 sysfs_remove_dir(kobj);
103 return error;
104 }
105 }
106
26ea12de
TH
107 /*
108 * @kobj->sd may be deleted by an ancestor going away. Hold an
109 * extra reference so that it stays until @kobj is gone.
110 */
111 sysfs_get(kobj->sd);
112
c84a3b27
TH
113 /*
114 * If @kobj has ns_ops, its children need to be filtered based on
115 * their namespace tags. Enable namespace support on @kobj->sd.
116 */
117 ops = kobj_child_ns_ops(kobj);
118 if (ops) {
119 BUG_ON(ops->type <= KOBJ_NS_TYPE_NONE);
120 BUG_ON(ops->type >= KOBJ_NS_TYPES);
121 BUG_ON(!kobj_ns_type_registered(ops->type));
122
fa4cd451 123 sysfs_enable_ns(kobj->sd);
c84a3b27
TH
124 }
125
126 return 0;
1da177e4
LT
127}
128
1da177e4
LT
129static int get_kobj_path_length(struct kobject *kobj)
130{
131 int length = 1;
e374a2bf 132 struct kobject *parent = kobj;
1da177e4 133
e374a2bf 134 /* walk up the ancestors until we hit the one pointing to the
1da177e4
LT
135 * root.
136 * Add 1 to strlen for leading '/' of each level.
137 */
138 do {
b365b3da
CE
139 if (kobject_name(parent) == NULL)
140 return 0;
1da177e4
LT
141 length += strlen(kobject_name(parent)) + 1;
142 parent = parent->parent;
143 } while (parent);
144 return length;
145}
146
147static void fill_kobj_path(struct kobject *kobj, char *path, int length)
148{
e374a2bf 149 struct kobject *parent;
1da177e4
LT
150
151 --length;
152 for (parent = kobj; parent; parent = parent->parent) {
153 int cur = strlen(kobject_name(parent));
154 /* back up enough to print this name with '/' */
155 length -= cur;
77d2a24b 156 memcpy(path + length, kobject_name(parent), cur);
1da177e4
LT
157 *(path + --length) = '/';
158 }
159
9f66fa2a 160 pr_debug("kobject: '%s' (%p): %s: path = '%s'\n", kobject_name(kobj),
810304db 161 kobj, __func__, path);
1da177e4
LT
162}
163
164/**
8fd7c302 165 * kobject_get_path() - Allocate memory and fill in the path for @kobj.
1da177e4
LT
166 * @kobj: kobject in question, with which to build the path
167 * @gfp_mask: the allocation type used to allocate the path
72fd4a35 168 *
8fd7c302 169 * Return: The newly allocated memory, caller must free with kfree().
1da177e4 170 */
fd4f2df2 171char *kobject_get_path(struct kobject *kobj, gfp_t gfp_mask)
1da177e4
LT
172{
173 char *path;
174 int len;
175
176 len = get_kobj_path_length(kobj);
b365b3da
CE
177 if (len == 0)
178 return NULL;
4668edc3 179 path = kzalloc(len, gfp_mask);
1da177e4
LT
180 if (!path)
181 return NULL;
1da177e4
LT
182 fill_kobj_path(kobj, path, len);
183
184 return path;
185}
80fc9f53 186EXPORT_SYMBOL_GPL(kobject_get_path);
1da177e4 187
0f4dafc0
KS
188/* add the kobject to its kset's list */
189static void kobj_kset_join(struct kobject *kobj)
1da177e4 190{
0f4dafc0 191 if (!kobj->kset)
31b9025a 192 return;
0f4dafc0
KS
193
194 kset_get(kobj->kset);
195 spin_lock(&kobj->kset->list_lock);
196 list_add_tail(&kobj->entry, &kobj->kset->list);
197 spin_unlock(&kobj->kset->list_lock);
1da177e4
LT
198}
199
0f4dafc0
KS
200/* remove the kobject from its kset's list */
201static void kobj_kset_leave(struct kobject *kobj)
202{
203 if (!kobj->kset)
204 return;
1da177e4 205
0f4dafc0
KS
206 spin_lock(&kobj->kset->list_lock);
207 list_del_init(&kobj->entry);
208 spin_unlock(&kobj->kset->list_lock);
209 kset_put(kobj->kset);
210}
1da177e4 211
e374a2bf 212static void kobject_init_internal(struct kobject *kobj)
1da177e4 213{
0f4dafc0
KS
214 if (!kobj)
215 return;
216 kref_init(&kobj->kref);
217 INIT_LIST_HEAD(&kobj->entry);
a4573c48
GKH
218 kobj->state_in_sysfs = 0;
219 kobj->state_add_uevent_sent = 0;
220 kobj->state_remove_uevent_sent = 0;
221 kobj->state_initialized = 1;
1da177e4
LT
222}
223
0f4dafc0 224
9e7bbccd 225static int kobject_add_internal(struct kobject *kobj)
1da177e4
LT
226{
227 int error = 0;
e374a2bf 228 struct kobject *parent;
1da177e4 229
0f4dafc0 230 if (!kobj)
1da177e4 231 return -ENOENT;
0f4dafc0 232
af5ca3f4 233 if (!kobj->name || !kobj->name[0]) {
82d1f117
AS
234 WARN(1,
235 "kobject: (%p): attempted to be registered with empty name!\n",
236 kobj);
c171fef5
GKH
237 return -EINVAL;
238 }
1da177e4 239
0f4dafc0 240 parent = kobject_get(kobj->parent);
1da177e4 241
0f4dafc0 242 /* join kset if set, use it as parent if we do not already have one */
1da177e4 243 if (kobj->kset) {
0f4dafc0 244 if (!parent)
1da177e4 245 parent = kobject_get(&kobj->kset->kobj);
0f4dafc0 246 kobj_kset_join(kobj);
460f7e9a 247 kobj->parent = parent;
1da177e4 248 }
1da177e4 249
0f4dafc0 250 pr_debug("kobject: '%s' (%p): %s: parent: '%s', set: '%s'\n",
810304db 251 kobject_name(kobj), kobj, __func__,
0f4dafc0 252 parent ? kobject_name(parent) : "<NULL>",
e374a2bf 253 kobj->kset ? kobject_name(&kobj->kset->kobj) : "<NULL>");
0f4dafc0 254
90bc6135 255 error = create_dir(kobj);
1da177e4 256 if (error) {
0f4dafc0
KS
257 kobj_kset_leave(kobj);
258 kobject_put(parent);
259 kobj->parent = NULL;
dcd0da00
GKH
260
261 /* be noisy on error issues */
262 if (error == -EEXIST)
3e14c6ab
DV
263 pr_err("%s failed for %s with -EEXIST, don't try to register things with the same name in the same directory.\n",
264 __func__, kobject_name(kobj));
dcd0da00 265 else
3e14c6ab
DV
266 pr_err("%s failed for %s (error: %d parent: %s)\n",
267 __func__, kobject_name(kobj), error,
268 parent ? kobject_name(parent) : "'none'");
0f4dafc0
KS
269 } else
270 kobj->state_in_sysfs = 1;
1da177e4
LT
271
272 return error;
273}
274
663a4743 275/**
ed856349 276 * kobject_set_name_vargs() - Set the name of a kobject.
663a4743
GKH
277 * @kobj: struct kobject to set the name of
278 * @fmt: format string used to build the name
279 * @vargs: vargs to format the string.
280 */
1fa5ae85 281int kobject_set_name_vargs(struct kobject *kobj, const char *fmt,
663a4743
GKH
282 va_list vargs)
283{
f773f32d 284 const char *s;
663a4743 285
8a577ffc
KS
286 if (kobj->name && !fmt)
287 return 0;
288
f773f32d 289 s = kvasprintf_const(GFP_KERNEL, fmt, vargs);
2abf114f 290 if (!s)
a4ca6617 291 return -ENOMEM;
663a4743 292
f773f32d
RV
293 /*
294 * ewww... some of these buggers have '/' in the name ... If
295 * that's the case, we need to make sure we have an actual
296 * allocated copy to modify, since kvasprintf_const may have
297 * returned something from .rodata.
298 */
299 if (strchr(s, '/')) {
300 char *t;
301
302 t = kstrdup(s, GFP_KERNEL);
303 kfree_const(s);
304 if (!t)
305 return -ENOMEM;
306 strreplace(t, '/', '!');
307 s = t;
308 }
309 kfree_const(kobj->name);
2abf114f 310 kobj->name = s;
9f255651 311
663a4743
GKH
312 return 0;
313}
1da177e4
LT
314
315/**
ed856349 316 * kobject_set_name() - Set the name of a kobject.
663a4743 317 * @kobj: struct kobject to set the name of
8c4606b1 318 * @fmt: format string used to build the name
1da177e4 319 *
8c4606b1
GKH
320 * This sets the name of the kobject. If you have already added the
321 * kobject to the system, you must call kobject_rename() in order to
322 * change the name of the kobject.
1da177e4 323 */
663a4743 324int kobject_set_name(struct kobject *kobj, const char *fmt, ...)
1da177e4 325{
a4ca6617 326 va_list vargs;
663a4743 327 int retval;
1da177e4 328
a4ca6617
KS
329 va_start(vargs, fmt);
330 retval = kobject_set_name_vargs(kobj, fmt, vargs);
331 va_end(vargs);
1da177e4 332
663a4743 333 return retval;
1da177e4 334}
1da177e4
LT
335EXPORT_SYMBOL(kobject_set_name);
336
e86000d0 337/**
ed856349 338 * kobject_init() - Initialize a kobject structure.
e86000d0
GKH
339 * @kobj: pointer to the kobject to initialize
340 * @ktype: pointer to the ktype for this kobject.
341 *
342 * This function will properly initialize a kobject such that it can then
343 * be passed to the kobject_add() call.
344 *
345 * After this function is called, the kobject MUST be cleaned up by a call
346 * to kobject_put(), not by a call to kfree directly to ensure that all of
347 * the memory is cleaned up properly.
348 */
f9cb074b 349void kobject_init(struct kobject *kobj, struct kobj_type *ktype)
e86000d0
GKH
350{
351 char *err_str;
352
353 if (!kobj) {
354 err_str = "invalid kobject pointer!";
355 goto error;
356 }
357 if (!ktype) {
358 err_str = "must have a ktype to be initialized properly!\n";
359 goto error;
360 }
0f4dafc0 361 if (kobj->state_initialized) {
e86000d0 362 /* do not error out as sometimes we can recover */
82d1f117
AS
363 pr_err("kobject (%p): tried to init an initialized object, something is seriously wrong.\n",
364 kobj);
e86000d0
GKH
365 dump_stack();
366 }
367
a4573c48 368 kobject_init_internal(kobj);
e86000d0
GKH
369 kobj->ktype = ktype;
370 return;
371
372error:
82d1f117 373 pr_err("kobject (%p): %s\n", kobj, err_str);
e86000d0
GKH
374 dump_stack();
375}
f9cb074b 376EXPORT_SYMBOL(kobject_init);
e86000d0 377
8db14860
NI
378static __printf(3, 0) int kobject_add_varg(struct kobject *kobj,
379 struct kobject *parent,
380 const char *fmt, va_list vargs)
244f6cee 381{
244f6cee
GKH
382 int retval;
383
a4ca6617 384 retval = kobject_set_name_vargs(kobj, fmt, vargs);
244f6cee 385 if (retval) {
82d1f117 386 pr_err("kobject: can not set name properly!\n");
244f6cee
GKH
387 return retval;
388 }
389 kobj->parent = parent;
9e7bbccd 390 return kobject_add_internal(kobj);
244f6cee
GKH
391}
392
393/**
ed856349 394 * kobject_add() - The main kobject add function.
244f6cee
GKH
395 * @kobj: the kobject to add
396 * @parent: pointer to the parent of the kobject.
397 * @fmt: format to name the kobject with.
398 *
399 * The kobject name is set and added to the kobject hierarchy in this
400 * function.
401 *
402 * If @parent is set, then the parent of the @kobj will be set to it.
403 * If @parent is NULL, then the parent of the @kobj will be set to the
9705710e 404 * kobject associated with the kset assigned to this kobject. If no kset
244f6cee
GKH
405 * is assigned to the kobject, then the kobject will be located in the
406 * root of the sysfs tree.
407 *
0f4dafc0 408 * Note, no "add" uevent will be created with this call, the caller should set
244f6cee
GKH
409 * up all of the necessary sysfs files for the object and then call
410 * kobject_uevent() with the UEVENT_ADD parameter to ensure that
411 * userspace is properly notified of this kobject's creation.
92067f84
TH
412 *
413 * Return: If this function returns an error, kobject_put() must be
414 * called to properly clean up the memory associated with the
415 * object. Under no instance should the kobject that is passed
416 * to this function be directly freed with a call to kfree(),
417 * that can leak memory.
418 *
70e16a62
GKH
419 * If this function returns success, kobject_put() must also be called
420 * in order to properly clean up the memory associated with the object.
421 *
422 * In short, once this function is called, kobject_put() MUST be called
423 * when the use of the object is finished in order to properly free
424 * everything.
244f6cee 425 */
b2d6db58
GKH
426int kobject_add(struct kobject *kobj, struct kobject *parent,
427 const char *fmt, ...)
244f6cee
GKH
428{
429 va_list args;
430 int retval;
431
432 if (!kobj)
433 return -EINVAL;
434
0f4dafc0 435 if (!kobj->state_initialized) {
82d1f117 436 pr_err("kobject '%s' (%p): tried to add an uninitialized object, something is seriously wrong.\n",
0f4dafc0
KS
437 kobject_name(kobj), kobj);
438 dump_stack();
439 return -EINVAL;
440 }
244f6cee
GKH
441 va_start(args, fmt);
442 retval = kobject_add_varg(kobj, parent, fmt, args);
443 va_end(args);
444
445 return retval;
446}
b2d6db58 447EXPORT_SYMBOL(kobject_add);
244f6cee 448
c11c4154 449/**
ed856349
TH
450 * kobject_init_and_add() - Initialize a kobject structure and add it to
451 * the kobject hierarchy.
c11c4154
GKH
452 * @kobj: pointer to the kobject to initialize
453 * @ktype: pointer to the ktype for this kobject.
454 * @parent: pointer to the parent of this kobject.
455 * @fmt: the name of the kobject.
456 *
1fd7c3b4
TH
457 * This function combines the call to kobject_init() and kobject_add().
458 *
459 * If this function returns an error, kobject_put() must be called to
460 * properly clean up the memory associated with the object. This is the
461 * same type of error handling after a call to kobject_add() and kobject
462 * lifetime rules are the same here.
c11c4154
GKH
463 */
464int kobject_init_and_add(struct kobject *kobj, struct kobj_type *ktype,
465 struct kobject *parent, const char *fmt, ...)
466{
467 va_list args;
468 int retval;
469
f9cb074b 470 kobject_init(kobj, ktype);
c11c4154
GKH
471
472 va_start(args, fmt);
473 retval = kobject_add_varg(kobj, parent, fmt, args);
474 va_end(args);
475
476 return retval;
477}
478EXPORT_SYMBOL_GPL(kobject_init_and_add);
479
1da177e4 480/**
ed856349 481 * kobject_rename() - Change the name of an object.
e374a2bf
GKH
482 * @kobj: object in question.
483 * @new_name: object's new name
030c1d2b
EB
484 *
485 * It is the responsibility of the caller to provide mutual
486 * exclusion between two different calls of kobject_rename
487 * on the same kobject and to ensure that new_name is valid and
488 * won't conflict with other kobjects.
1da177e4 489 */
e374a2bf 490int kobject_rename(struct kobject *kobj, const char *new_name)
1da177e4
LT
491{
492 int error = 0;
ca2f37db 493 const char *devpath = NULL;
0b4a4fea 494 const char *dup_name = NULL, *name;
ca2f37db
JT
495 char *devpath_string = NULL;
496 char *envp[2];
1da177e4
LT
497
498 kobj = kobject_get(kobj);
499 if (!kobj)
500 return -EINVAL;
122f8ec7
LY
501 if (!kobj->parent) {
502 kobject_put(kobj);
b592fcfe 503 return -EINVAL;
122f8ec7 504 }
ca2f37db
JT
505
506 devpath = kobject_get_path(kobj, GFP_KERNEL);
507 if (!devpath) {
508 error = -ENOMEM;
509 goto out;
510 }
511 devpath_string = kmalloc(strlen(devpath) + 15, GFP_KERNEL);
512 if (!devpath_string) {
513 error = -ENOMEM;
514 goto out;
515 }
516 sprintf(devpath_string, "DEVPATH_OLD=%s", devpath);
517 envp[0] = devpath_string;
518 envp[1] = NULL;
ca2f37db 519
f773f32d 520 name = dup_name = kstrdup_const(new_name, GFP_KERNEL);
0b4a4fea
EB
521 if (!name) {
522 error = -ENOMEM;
523 goto out;
524 }
525
e34ff490 526 error = sysfs_rename_dir_ns(kobj, new_name, kobject_namespace(kobj));
0b4a4fea
EB
527 if (error)
528 goto out;
529
530 /* Install the new kobject name */
531 dup_name = kobj->name;
532 kobj->name = name;
ca2f37db
JT
533
534 /* This function is mostly/only used for network interface.
535 * Some hotplug package track interfaces by their name and
536 * therefore want to know when the name is changed by the user. */
0b4a4fea 537 kobject_uevent_env(kobj, KOBJ_MOVE, envp);
ca2f37db
JT
538
539out:
f773f32d 540 kfree_const(dup_name);
ca2f37db
JT
541 kfree(devpath_string);
542 kfree(devpath);
b592fcfe
EB
543 kobject_put(kobj);
544
545 return error;
546}
8344b568 547EXPORT_SYMBOL_GPL(kobject_rename);
b592fcfe 548
8a82472f 549/**
ed856349 550 * kobject_move() - Move object to another parent.
e374a2bf
GKH
551 * @kobj: object in question.
552 * @new_parent: object's new parent (can be NULL)
8a82472f 553 */
8a82472f
CH
554int kobject_move(struct kobject *kobj, struct kobject *new_parent)
555{
556 int error;
557 struct kobject *old_parent;
558 const char *devpath = NULL;
559 char *devpath_string = NULL;
560 char *envp[2];
561
562 kobj = kobject_get(kobj);
563 if (!kobj)
564 return -EINVAL;
565 new_parent = kobject_get(new_parent);
566 if (!new_parent) {
c744aeae
CH
567 if (kobj->kset)
568 new_parent = kobject_get(&kobj->kset->kobj);
8a82472f 569 }
e34ff490 570
8a82472f
CH
571 /* old object path */
572 devpath = kobject_get_path(kobj, GFP_KERNEL);
573 if (!devpath) {
574 error = -ENOMEM;
575 goto out;
576 }
577 devpath_string = kmalloc(strlen(devpath) + 15, GFP_KERNEL);
578 if (!devpath_string) {
579 error = -ENOMEM;
580 goto out;
581 }
582 sprintf(devpath_string, "DEVPATH_OLD=%s", devpath);
583 envp[0] = devpath_string;
584 envp[1] = NULL;
e34ff490 585 error = sysfs_move_dir_ns(kobj, new_parent, kobject_namespace(kobj));
8a82472f
CH
586 if (error)
587 goto out;
588 old_parent = kobj->parent;
589 kobj->parent = new_parent;
9e993efb 590 new_parent = NULL;
8a82472f
CH
591 kobject_put(old_parent);
592 kobject_uevent_env(kobj, KOBJ_MOVE, envp);
593out:
9e993efb 594 kobject_put(new_parent);
8a82472f
CH
595 kobject_put(kobj);
596 kfree(devpath_string);
597 kfree(devpath);
598 return error;
599}
24199d20 600EXPORT_SYMBOL_GPL(kobject_move);
8a82472f 601
079ad2fb 602static void __kobject_del(struct kobject *kobj)
1da177e4 603{
324a56e1 604 struct kernfs_node *sd;
3d378dc7 605 const struct kobj_type *ktype;
26ea12de 606
26ea12de 607 sd = kobj->sd;
3d378dc7 608 ktype = get_ktype(kobj);
aa30f47c
KB
609
610 if (ktype)
611 sysfs_remove_groups(kobj, ktype->default_groups);
612
0e5596c5
GKH
613 /* send "remove" if the caller did not do it but sent "add" */
614 if (kobj->state_add_uevent_sent && !kobj->state_remove_uevent_sent) {
615 pr_debug("kobject: '%s' (%p): auto cleanup 'remove' event\n",
616 kobject_name(kobj), kobj);
617 kobject_uevent(kobj, KOBJ_REMOVE);
618 }
619
1da177e4 620 sysfs_remove_dir(kobj);
26ea12de
TH
621 sysfs_put(sd);
622
0f4dafc0
KS
623 kobj->state_in_sysfs = 0;
624 kobj_kset_leave(kobj);
0f4dafc0 625 kobj->parent = NULL;
1da177e4 626}
079ad2fb
HK
627
628/**
629 * kobject_del() - Unlink kobject from hierarchy.
630 * @kobj: object.
631 *
632 * This is the function that should be called to delete an object
633 * successfully added via kobject_add().
634 */
635void kobject_del(struct kobject *kobj)
636{
40b8b826
AS
637 struct kobject *parent;
638
639 if (!kobj)
640 return;
079ad2fb 641
40b8b826 642 parent = kobj->parent;
079ad2fb
HK
643 __kobject_del(kobj);
644 kobject_put(parent);
645}
fa40ae34 646EXPORT_SYMBOL(kobject_del);
1da177e4 647
1da177e4 648/**
ed856349 649 * kobject_get() - Increment refcount for object.
e374a2bf 650 * @kobj: object.
1da177e4 651 */
e374a2bf 652struct kobject *kobject_get(struct kobject *kobj)
1da177e4 653{
d82d54af
EZ
654 if (kobj) {
655 if (!kobj->state_initialized)
82d1f117
AS
656 WARN(1, KERN_WARNING
657 "kobject: '%s' (%p): is not initialized, yet kobject_get() is being called.\n",
658 kobject_name(kobj), kobj);
1da177e4 659 kref_get(&kobj->kref);
d82d54af 660 }
1da177e4
LT
661 return kobj;
662}
fa40ae34 663EXPORT_SYMBOL(kobject_get);
1da177e4 664
c70c176f 665struct kobject * __must_check kobject_get_unless_zero(struct kobject *kobj)
a49b7e82 666{
c70c176f
JK
667 if (!kobj)
668 return NULL;
a49b7e82
LT
669 if (!kref_get_unless_zero(&kobj->kref))
670 kobj = NULL;
671 return kobj;
672}
c70c176f 673EXPORT_SYMBOL(kobject_get_unless_zero);
a49b7e82 674
18041f47
GKH
675/*
676 * kobject_cleanup - free kobject resources.
677 * @kobj: object to cleanup
1da177e4 678 */
18041f47 679static void kobject_cleanup(struct kobject *kobj)
1da177e4 680{
079ad2fb 681 struct kobject *parent = kobj->parent;
0f4dafc0 682 struct kobj_type *t = get_ktype(kobj);
af5ca3f4 683 const char *name = kobj->name;
1da177e4 684
c817a67e
RK
685 pr_debug("kobject: '%s' (%p): %s, parent %p\n",
686 kobject_name(kobj), kobj, __func__, kobj->parent);
0f4dafc0
KS
687
688 if (t && !t->release)
0c1bc6b8 689 pr_debug("kobject: '%s' (%p): does not have a release() function, it is broken and must be fixed. See Documentation/core-api/kobject.rst.\n",
0f4dafc0
KS
690 kobject_name(kobj), kobj);
691
0f4dafc0
KS
692 /* remove from sysfs if the caller did not do it */
693 if (kobj->state_in_sysfs) {
694 pr_debug("kobject: '%s' (%p): auto cleanup kobject_del\n",
695 kobject_name(kobj), kobj);
079ad2fb
HK
696 __kobject_del(kobj);
697 } else {
698 /* avoid dropping the parent reference unnecessarily */
699 parent = NULL;
0f4dafc0
KS
700 }
701
ce2c9cb0 702 if (t && t->release) {
0f4dafc0
KS
703 pr_debug("kobject: '%s' (%p): calling ktype release\n",
704 kobject_name(kobj), kobj);
1da177e4 705 t->release(kobj);
0f4dafc0
KS
706 }
707
708 /* free name if we allocated it */
af5ca3f4 709 if (name) {
0f4dafc0 710 pr_debug("kobject: '%s': free name\n", name);
f773f32d 711 kfree_const(name);
ce2c9cb0 712 }
079ad2fb
HK
713
714 kobject_put(parent);
1da177e4
LT
715}
716
c817a67e
RK
717#ifdef CONFIG_DEBUG_KOBJECT_RELEASE
718static void kobject_delayed_cleanup(struct work_struct *work)
719{
720 kobject_cleanup(container_of(to_delayed_work(work),
721 struct kobject, release));
722}
723#endif
724
1da177e4
LT
725static void kobject_release(struct kref *kref)
726{
c817a67e
RK
727 struct kobject *kobj = container_of(kref, struct kobject, kref);
728#ifdef CONFIG_DEBUG_KOBJECT_RELEASE
89c86a64
BH
729 unsigned long delay = HZ + HZ * (get_random_int() & 0x3);
730 pr_info("kobject: '%s' (%p): %s, parent %p (delayed %ld)\n",
731 kobject_name(kobj), kobj, __func__, kobj->parent, delay);
c817a67e 732 INIT_DELAYED_WORK(&kobj->release, kobject_delayed_cleanup);
89c86a64
BH
733
734 schedule_delayed_work(&kobj->release, delay);
c817a67e
RK
735#else
736 kobject_cleanup(kobj);
737#endif
1da177e4
LT
738}
739
740/**
ed856349 741 * kobject_put() - Decrement refcount for object.
e374a2bf 742 * @kobj: object.
1da177e4 743 *
e374a2bf 744 * Decrement the refcount, and if 0, call kobject_cleanup().
1da177e4 745 */
e374a2bf 746void kobject_put(struct kobject *kobj)
1da177e4 747{
c1ebdae5 748 if (kobj) {
d955c78a 749 if (!kobj->state_initialized)
82d1f117
AS
750 WARN(1, KERN_WARNING
751 "kobject: '%s' (%p): is not initialized, yet kobject_put() is being called.\n",
752 kobject_name(kobj), kobj);
1da177e4 753 kref_put(&kobj->kref, kobject_release);
c1ebdae5 754 }
1da177e4 755}
fa40ae34 756EXPORT_SYMBOL(kobject_put);
1da177e4 757
3f9e3ee9 758static void dynamic_kobj_release(struct kobject *kobj)
7423172a 759{
810304db 760 pr_debug("kobject: (%p): %s\n", kobj, __func__);
7423172a
JN
761 kfree(kobj);
762}
763
3f9e3ee9 764static struct kobj_type dynamic_kobj_ktype = {
386f275f
KS
765 .release = dynamic_kobj_release,
766 .sysfs_ops = &kobj_sysfs_ops,
7423172a
JN
767};
768
43968d2f 769/**
ed856349 770 * kobject_create() - Create a struct kobject dynamically.
3f9e3ee9
GKH
771 *
772 * This function creates a kobject structure dynamically and sets it up
773 * to be a "dynamic" kobject with a default release function set up.
774 *
775 * If the kobject was not able to be created, NULL will be returned.
43968d2f 776 * The kobject structure returned from here must be cleaned up with a
f9cb074b 777 * call to kobject_put() and not kfree(), as kobject_init() has
43968d2f 778 * already been called on this structure.
3f9e3ee9 779 */
43968d2f 780struct kobject *kobject_create(void)
3f9e3ee9
GKH
781{
782 struct kobject *kobj;
783
784 kobj = kzalloc(sizeof(*kobj), GFP_KERNEL);
785 if (!kobj)
786 return NULL;
787
f9cb074b 788 kobject_init(kobj, &dynamic_kobj_ktype);
3f9e3ee9
GKH
789 return kobj;
790}
791
792/**
ed856349
TH
793 * kobject_create_and_add() - Create a struct kobject dynamically and
794 * register it with sysfs.
9ff1f838 795 * @name: the name for the kobject
3f9e3ee9
GKH
796 * @parent: the parent kobject of this kobject, if any.
797 *
f70701a3 798 * This function creates a kobject structure dynamically and registers it
3f9e3ee9 799 * with sysfs. When you are finished with this structure, call
78a2d906 800 * kobject_put() and the structure will be dynamically freed when
3f9e3ee9
GKH
801 * it is no longer being used.
802 *
803 * If the kobject was not able to be created, NULL will be returned.
804 */
805struct kobject *kobject_create_and_add(const char *name, struct kobject *parent)
806{
807 struct kobject *kobj;
808 int retval;
809
810 kobj = kobject_create();
811 if (!kobj)
812 return NULL;
813
b2d6db58 814 retval = kobject_add(kobj, parent, "%s", name);
3f9e3ee9 815 if (retval) {
82d1f117 816 pr_warn("%s: kobject_add error: %d\n", __func__, retval);
3f9e3ee9
GKH
817 kobject_put(kobj);
818 kobj = NULL;
819 }
820 return kobj;
821}
822EXPORT_SYMBOL_GPL(kobject_create_and_add);
823
1da177e4 824/**
ed856349 825 * kset_init() - Initialize a kset for use.
e374a2bf 826 * @k: kset
1da177e4 827 */
e374a2bf 828void kset_init(struct kset *k)
1da177e4 829{
e1543ddf 830 kobject_init_internal(&k->kobj);
1da177e4
LT
831 INIT_LIST_HEAD(&k->list);
832 spin_lock_init(&k->list_lock);
833}
834
23b5212c
KS
835/* default kobject attribute operations */
836static ssize_t kobj_attr_show(struct kobject *kobj, struct attribute *attr,
837 char *buf)
838{
839 struct kobj_attribute *kattr;
840 ssize_t ret = -EIO;
841
842 kattr = container_of(attr, struct kobj_attribute, attr);
843 if (kattr->show)
844 ret = kattr->show(kobj, kattr, buf);
845 return ret;
846}
847
848static ssize_t kobj_attr_store(struct kobject *kobj, struct attribute *attr,
849 const char *buf, size_t count)
850{
851 struct kobj_attribute *kattr;
852 ssize_t ret = -EIO;
853
854 kattr = container_of(attr, struct kobj_attribute, attr);
855 if (kattr->store)
856 ret = kattr->store(kobj, kattr, buf, count);
857 return ret;
858}
859
52cf25d0 860const struct sysfs_ops kobj_sysfs_ops = {
23b5212c
KS
861 .show = kobj_attr_show,
862 .store = kobj_attr_store,
863};
29dfe2dc 864EXPORT_SYMBOL_GPL(kobj_sysfs_ops);
1da177e4 865
1da177e4 866/**
ed856349 867 * kset_register() - Initialize and add a kset.
e374a2bf 868 * @k: kset.
1da177e4 869 */
e374a2bf 870int kset_register(struct kset *k)
1da177e4 871{
80f03e34
KS
872 int err;
873
31b9025a
GKH
874 if (!k)
875 return -EINVAL;
80f03e34 876
1da177e4 877 kset_init(k);
12e339ac 878 err = kobject_add_internal(&k->kobj);
80f03e34
KS
879 if (err)
880 return err;
881 kobject_uevent(&k->kobj, KOBJ_ADD);
882 return 0;
1da177e4 883}
fa40ae34 884EXPORT_SYMBOL(kset_register);
1da177e4 885
1da177e4 886/**
ed856349 887 * kset_unregister() - Remove a kset.
e374a2bf 888 * @k: kset.
1da177e4 889 */
e374a2bf 890void kset_unregister(struct kset *k)
1da177e4 891{
31b9025a
GKH
892 if (!k)
893 return;
35a5fe69 894 kobject_del(&k->kobj);
78a2d906 895 kobject_put(&k->kobj);
1da177e4 896}
fa40ae34 897EXPORT_SYMBOL(kset_unregister);
1da177e4 898
1da177e4 899/**
ed856349 900 * kset_find_obj() - Search for object in kset.
e374a2bf
GKH
901 * @kset: kset we're looking in.
902 * @name: object's name.
1da177e4 903 *
e374a2bf
GKH
904 * Lock kset via @kset->subsys, and iterate over @kset->list,
905 * looking for a matching kobject. If matching object is found
906 * take a reference and return the object.
1da177e4 907 */
e374a2bf 908struct kobject *kset_find_obj(struct kset *kset, const char *name)
1da177e4 909{
c6a2a3dc 910 struct kobject *k;
e374a2bf 911 struct kobject *ret = NULL;
1da177e4
LT
912
913 spin_lock(&kset->list_lock);
c25d1dfb 914
c6a2a3dc 915 list_for_each_entry(k, &kset->list, entry) {
e374a2bf 916 if (kobject_name(k) && !strcmp(kobject_name(k), name)) {
a49b7e82 917 ret = kobject_get_unless_zero(k);
1da177e4
LT
918 break;
919 }
920 }
c25d1dfb 921
1da177e4
LT
922 spin_unlock(&kset->list_lock);
923 return ret;
924}
2fe829ac 925EXPORT_SYMBOL_GPL(kset_find_obj);
1da177e4 926
b727c702
GKH
927static void kset_release(struct kobject *kobj)
928{
929 struct kset *kset = container_of(kobj, struct kset, kobj);
9f66fa2a 930 pr_debug("kobject: '%s' (%p): %s\n",
810304db 931 kobject_name(kobj), kobj, __func__);
b727c702
GKH
932 kfree(kset);
933}
934
7ab35a14 935static void kset_get_ownership(struct kobject *kobj, kuid_t *uid, kgid_t *gid)
d028b6f7
DT
936{
937 if (kobj->parent)
938 kobject_get_ownership(kobj->parent, uid, gid);
939}
940
386f275f
KS
941static struct kobj_type kset_ktype = {
942 .sysfs_ops = &kobj_sysfs_ops,
d028b6f7
DT
943 .release = kset_release,
944 .get_ownership = kset_get_ownership,
b727c702
GKH
945};
946
947/**
ed856349 948 * kset_create() - Create a struct kset dynamically.
b727c702
GKH
949 *
950 * @name: the name for the kset
951 * @uevent_ops: a struct kset_uevent_ops for the kset
952 * @parent_kobj: the parent kobject of this kset, if any.
953 *
954 * This function creates a kset structure dynamically. This structure can
955 * then be registered with the system and show up in sysfs with a call to
956 * kset_register(). When you are finished with this structure, if
957 * kset_register() has been called, call kset_unregister() and the
958 * structure will be dynamically freed when it is no longer being used.
959 *
960 * If the kset was not able to be created, NULL will be returned.
961 */
962static struct kset *kset_create(const char *name,
9cd43611 963 const struct kset_uevent_ops *uevent_ops,
b727c702
GKH
964 struct kobject *parent_kobj)
965{
966 struct kset *kset;
d9cd8f37 967 int retval;
b727c702
GKH
968
969 kset = kzalloc(sizeof(*kset), GFP_KERNEL);
970 if (!kset)
971 return NULL;
b7165ebb 972 retval = kobject_set_name(&kset->kobj, "%s", name);
d9cd8f37
DY
973 if (retval) {
974 kfree(kset);
975 return NULL;
976 }
b727c702
GKH
977 kset->uevent_ops = uevent_ops;
978 kset->kobj.parent = parent_kobj;
979
980 /*
386f275f 981 * The kobject of this kset will have a type of kset_ktype and belong to
b727c702
GKH
982 * no kset itself. That way we can properly free it when it is
983 * finished being used.
984 */
386f275f 985 kset->kobj.ktype = &kset_ktype;
b727c702
GKH
986 kset->kobj.kset = NULL;
987
988 return kset;
989}
990
991/**
ed856349 992 * kset_create_and_add() - Create a struct kset dynamically and add it to sysfs.
b727c702
GKH
993 *
994 * @name: the name for the kset
995 * @uevent_ops: a struct kset_uevent_ops for the kset
996 * @parent_kobj: the parent kobject of this kset, if any.
997 *
998 * This function creates a kset structure dynamically and registers it
999 * with sysfs. When you are finished with this structure, call
1000 * kset_unregister() and the structure will be dynamically freed when it
1001 * is no longer being used.
1002 *
1003 * If the kset was not able to be created, NULL will be returned.
1004 */
1005struct kset *kset_create_and_add(const char *name,
9cd43611 1006 const struct kset_uevent_ops *uevent_ops,
b727c702
GKH
1007 struct kobject *parent_kobj)
1008{
1009 struct kset *kset;
1010 int error;
1011
1012 kset = kset_create(name, uevent_ops, parent_kobj);
1013 if (!kset)
1014 return NULL;
1015 error = kset_register(kset);
1016 if (error) {
1017 kfree(kset);
1018 return NULL;
1019 }
1020 return kset;
1021}
1022EXPORT_SYMBOL_GPL(kset_create_and_add);
1023
bc451f20
EB
1024
1025static DEFINE_SPINLOCK(kobj_ns_type_lock);
1026static const struct kobj_ns_type_operations *kobj_ns_ops_tbl[KOBJ_NS_TYPES];
1027
1028int kobj_ns_type_register(const struct kobj_ns_type_operations *ops)
1029{
1030 enum kobj_ns_type type = ops->type;
1031 int error;
1032
1033 spin_lock(&kobj_ns_type_lock);
1034
1035 error = -EINVAL;
1036 if (type >= KOBJ_NS_TYPES)
1037 goto out;
1038
1039 error = -EINVAL;
1040 if (type <= KOBJ_NS_TYPE_NONE)
1041 goto out;
1042
1043 error = -EBUSY;
1044 if (kobj_ns_ops_tbl[type])
1045 goto out;
1046
1047 error = 0;
1048 kobj_ns_ops_tbl[type] = ops;
1049
1050out:
1051 spin_unlock(&kobj_ns_type_lock);
1052 return error;
1053}
1054
1055int kobj_ns_type_registered(enum kobj_ns_type type)
1056{
1057 int registered = 0;
1058
1059 spin_lock(&kobj_ns_type_lock);
1060 if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES))
1061 registered = kobj_ns_ops_tbl[type] != NULL;
1062 spin_unlock(&kobj_ns_type_lock);
1063
1064 return registered;
1065}
1066
1067const struct kobj_ns_type_operations *kobj_child_ns_ops(struct kobject *parent)
1068{
1069 const struct kobj_ns_type_operations *ops = NULL;
1070
41fb96a4 1071 if (parent && parent->ktype && parent->ktype->child_ns_type)
bc451f20
EB
1072 ops = parent->ktype->child_ns_type(parent);
1073
1074 return ops;
1075}
1076
1077const struct kobj_ns_type_operations *kobj_ns_ops(struct kobject *kobj)
1078{
1079 return kobj_child_ns_ops(kobj->parent);
1080}
1081
7dc5dbc8
EB
1082bool kobj_ns_current_may_mount(enum kobj_ns_type type)
1083{
730d7d33 1084 bool may_mount = true;
7dc5dbc8
EB
1085
1086 spin_lock(&kobj_ns_type_lock);
1087 if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
1088 kobj_ns_ops_tbl[type])
1089 may_mount = kobj_ns_ops_tbl[type]->current_may_mount();
1090 spin_unlock(&kobj_ns_type_lock);
1091
1092 return may_mount;
1093}
bc451f20 1094
a685e089 1095void *kobj_ns_grab_current(enum kobj_ns_type type)
bc451f20 1096{
a685e089 1097 void *ns = NULL;
bc451f20
EB
1098
1099 spin_lock(&kobj_ns_type_lock);
1100 if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
1101 kobj_ns_ops_tbl[type])
a685e089 1102 ns = kobj_ns_ops_tbl[type]->grab_current_ns();
bc451f20
EB
1103 spin_unlock(&kobj_ns_type_lock);
1104
1105 return ns;
1106}
172856ea 1107EXPORT_SYMBOL_GPL(kobj_ns_grab_current);
bc451f20
EB
1108
1109const void *kobj_ns_netlink(enum kobj_ns_type type, struct sock *sk)
1110{
1111 const void *ns = NULL;
1112
1113 spin_lock(&kobj_ns_type_lock);
1114 if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
1115 kobj_ns_ops_tbl[type])
1116 ns = kobj_ns_ops_tbl[type]->netlink_ns(sk);
1117 spin_unlock(&kobj_ns_type_lock);
1118
1119 return ns;
1120}
1121
1122const void *kobj_ns_initial(enum kobj_ns_type type)
1123{
1124 const void *ns = NULL;
1125
1126 spin_lock(&kobj_ns_type_lock);
1127 if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
1128 kobj_ns_ops_tbl[type])
1129 ns = kobj_ns_ops_tbl[type]->initial_ns();
1130 spin_unlock(&kobj_ns_type_lock);
1131
1132 return ns;
1133}
1134
a685e089 1135void kobj_ns_drop(enum kobj_ns_type type, void *ns)
bc451f20 1136{
a685e089
AV
1137 spin_lock(&kobj_ns_type_lock);
1138 if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
1139 kobj_ns_ops_tbl[type] && kobj_ns_ops_tbl[type]->drop_ns)
1140 kobj_ns_ops_tbl[type]->drop_ns(ns);
1141 spin_unlock(&kobj_ns_type_lock);
bc451f20 1142}
172856ea 1143EXPORT_SYMBOL_GPL(kobj_ns_drop);