blob: 39a01993676864e56b55f8125155646f808f4f40 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * fs/sysfs/group.c - Operations for adding/removing multiple files at once.
3 *
4 * Copyright (c) 2003 Patrick Mochel
5 * Copyright (c) 2003 Open Source Development Lab
Greg Kroah-Hartman9e2a47e2013-08-21 16:14:11 -07006 * Copyright (c) 2013 Greg Kroah-Hartman
7 * Copyright (c) 2013 The Linux Foundation
Linus Torvalds1da177e2005-04-16 15:20:36 -07008 *
Greg Kroah-Hartmane6c56922013-08-21 16:06:14 -07009 * This file is released undert the GPL v2.
Linus Torvalds1da177e2005-04-16 15:20:36 -070010 *
11 */
12
13#include <linux/kobject.h>
14#include <linux/module.h>
15#include <linux/dcache.h>
Christoph Hellwig5f45f1a2005-06-23 00:09:12 -070016#include <linux/namei.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#include <linux/err.h>
18#include "sysfs.h"
19
20
Robert ABEL9f70a402014-05-05 15:17:20 +020021static void remove_files(struct kernfs_node *parent,
Tejun Heo608e2662007-06-14 04:27:22 +090022 const struct attribute_group *grp)
Linus Torvalds1da177e2005-04-16 15:20:36 -070023{
Greg Kroah-Hartman995d8ed2013-08-21 16:07:29 -070024 struct attribute *const *attr;
25 struct bin_attribute *const *bin_attr;
Linus Torvalds1da177e2005-04-16 15:20:36 -070026
Greg Kroah-Hartman6ab9cea2013-07-14 16:05:55 -070027 if (grp->attrs)
28 for (attr = grp->attrs; *attr; attr++)
Tejun Heo324a56e2013-12-11 14:11:53 -050029 kernfs_remove_by_name(parent, (*attr)->name);
Greg Kroah-Hartman6ab9cea2013-07-14 16:05:55 -070030 if (grp->bin_attrs)
31 for (bin_attr = grp->bin_attrs; *bin_attr; bin_attr++)
Robert ABEL9f70a402014-05-05 15:17:20 +020032 kernfs_remove_by_name(parent, (*bin_attr)->attr.name);
Linus Torvalds1da177e2005-04-16 15:20:36 -070033}
34
Tejun Heo324a56e2013-12-11 14:11:53 -050035static int create_files(struct kernfs_node *parent, struct kobject *kobj,
James Bottomley0f423892008-03-20 20:47:52 -050036 const struct attribute_group *grp, int update)
Linus Torvalds1da177e2005-04-16 15:20:36 -070037{
Greg Kroah-Hartman995d8ed2013-08-21 16:07:29 -070038 struct attribute *const *attr;
39 struct bin_attribute *const *bin_attr;
James Bottomleyd4acd722007-10-31 09:38:04 -050040 int error = 0, i;
Linus Torvalds1da177e2005-04-16 15:20:36 -070041
Greg Kroah-Hartman6ab9cea2013-07-14 16:05:55 -070042 if (grp->attrs) {
43 for (i = 0, attr = grp->attrs; *attr && !error; i++, attr++) {
Guenter Roeckda4759c2015-03-12 09:58:26 -040044 umode_t mode = (*attr)->mode;
James Bottomley0f423892008-03-20 20:47:52 -050045
Greg Kroah-Hartman6ab9cea2013-07-14 16:05:55 -070046 /*
47 * In update mode, we're changing the permissions or
48 * visibility. Do this by first removing then
49 * re-adding (if required) the file.
50 */
51 if (update)
Tejun Heo324a56e2013-12-11 14:11:53 -050052 kernfs_remove_by_name(parent, (*attr)->name);
Greg Kroah-Hartman6ab9cea2013-07-14 16:05:55 -070053 if (grp->is_visible) {
54 mode = grp->is_visible(kobj, *attr, i);
55 if (!mode)
56 continue;
57 }
Vivien Didelotd8bf8c92015-03-12 09:58:27 -040058
59 WARN(mode & ~(SYSFS_PREALLOC | 0664),
60 "Attribute %s: Invalid permissions 0%o\n",
61 (*attr)->name, mode);
62
63 mode &= SYSFS_PREALLOC | 0664;
Tejun Heo324a56e2013-12-11 14:11:53 -050064 error = sysfs_add_file_mode_ns(parent, *attr, false,
Guenter Roeckda4759c2015-03-12 09:58:26 -040065 mode, NULL);
Greg Kroah-Hartman6ab9cea2013-07-14 16:05:55 -070066 if (unlikely(error))
67 break;
James Bottomley0f423892008-03-20 20:47:52 -050068 }
Greg Kroah-Hartman6ab9cea2013-07-14 16:05:55 -070069 if (error) {
Robert ABEL9f70a402014-05-05 15:17:20 +020070 remove_files(parent, grp);
Greg Kroah-Hartman6ab9cea2013-07-14 16:05:55 -070071 goto exit;
72 }
James Bottomley0f423892008-03-20 20:47:52 -050073 }
Greg Kroah-Hartman6ab9cea2013-07-14 16:05:55 -070074
75 if (grp->bin_attrs) {
76 for (bin_attr = grp->bin_attrs; *bin_attr; bin_attr++) {
77 if (update)
Cody P Schaferaabaf4c2014-02-14 14:02:07 -080078 kernfs_remove_by_name(parent,
79 (*bin_attr)->attr.name);
80 error = sysfs_add_file_mode_ns(parent,
81 &(*bin_attr)->attr, true,
82 (*bin_attr)->attr.mode, NULL);
Greg Kroah-Hartman6ab9cea2013-07-14 16:05:55 -070083 if (error)
84 break;
85 }
86 if (error)
Robert ABEL9f70a402014-05-05 15:17:20 +020087 remove_files(parent, grp);
Greg Kroah-Hartman6ab9cea2013-07-14 16:05:55 -070088 }
89exit:
Linus Torvalds1da177e2005-04-16 15:20:36 -070090 return error;
91}
92
93
James Bottomley0f423892008-03-20 20:47:52 -050094static int internal_create_group(struct kobject *kobj, int update,
95 const struct attribute_group *grp)
Linus Torvalds1da177e2005-04-16 15:20:36 -070096{
Tejun Heo324a56e2013-12-11 14:11:53 -050097 struct kernfs_node *kn;
Linus Torvalds1da177e2005-04-16 15:20:36 -070098 int error;
99
James Bottomley0f423892008-03-20 20:47:52 -0500100 BUG_ON(!kobj || (!update && !kobj->sd));
101
102 /* Updates may happen before the object has been instantiated */
103 if (unlikely(update && !kobj->sd))
104 return -EINVAL;
Oliver Schinagl388a8c32013-07-14 16:05:56 -0700105 if (!grp->attrs && !grp->bin_attrs) {
106 WARN(1, "sysfs: (bin_)attrs not set by subsystem for group: %s/%s\n",
Javi Merinoadf305f2015-01-15 16:17:45 +0000107 kobj->name, grp->name ?: "");
Bruno Prémont5631f2c2012-04-03 09:59:48 +0200108 return -EINVAL;
109 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110 if (grp->name) {
Tejun Heobb8b9d092013-12-11 16:02:55 -0500111 kn = kernfs_create_dir(kobj->sd, grp->name,
112 S_IRWXU | S_IRUGO | S_IXUGO, kobj);
Tejun Heo324a56e2013-12-11 14:11:53 -0500113 if (IS_ERR(kn)) {
114 if (PTR_ERR(kn) == -EEXIST)
Tejun Heo93b2b8e2013-11-28 14:54:15 -0500115 sysfs_warn_dup(kobj->sd, grp->name);
Tejun Heo324a56e2013-12-11 14:11:53 -0500116 return PTR_ERR(kn);
Tejun Heo93b2b8e2013-11-28 14:54:15 -0500117 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118 } else
Tejun Heo324a56e2013-12-11 14:11:53 -0500119 kn = kobj->sd;
120 kernfs_get(kn);
121 error = create_files(kn, kobj, grp, update);
Tejun Heo608e2662007-06-14 04:27:22 +0900122 if (error) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700123 if (grp->name)
Tejun Heo324a56e2013-12-11 14:11:53 -0500124 kernfs_remove(kn);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125 }
Tejun Heo324a56e2013-12-11 14:11:53 -0500126 kernfs_put(kn);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127 return error;
128}
129
James Bottomley0f423892008-03-20 20:47:52 -0500130/**
131 * sysfs_create_group - given a directory kobject, create an attribute group
132 * @kobj: The kobject to create the group on
133 * @grp: The attribute group to create
134 *
135 * This function creates a group for the first time. It will explicitly
136 * warn and error if any of the attribute files being created already exist.
137 *
Antonio Ospiteed1dc8a82015-04-29 10:55:46 +0200138 * Returns 0 on success or error code on failure.
James Bottomley0f423892008-03-20 20:47:52 -0500139 */
140int sysfs_create_group(struct kobject *kobj,
141 const struct attribute_group *grp)
142{
143 return internal_create_group(kobj, 0, grp);
144}
Greg Kroah-Hartmand363bc52013-08-21 16:04:12 -0700145EXPORT_SYMBOL_GPL(sysfs_create_group);
James Bottomley0f423892008-03-20 20:47:52 -0500146
147/**
Greg Kroah-Hartman3e9b2ba2013-08-21 13:47:50 -0700148 * sysfs_create_groups - given a directory kobject, create a bunch of attribute groups
149 * @kobj: The kobject to create the group on
150 * @groups: The attribute groups to create, NULL terminated
151 *
152 * This function creates a bunch of attribute groups. If an error occurs when
153 * creating a group, all previously created groups will be removed, unwinding
154 * everything back to the original state when this function was called.
155 * It will explicitly warn and error if any of the attribute files being
156 * created already exist.
157 *
Antonio Ospiteed1dc8a82015-04-29 10:55:46 +0200158 * Returns 0 on success or error code from sysfs_create_group on failure.
Greg Kroah-Hartman3e9b2ba2013-08-21 13:47:50 -0700159 */
160int sysfs_create_groups(struct kobject *kobj,
161 const struct attribute_group **groups)
162{
163 int error = 0;
164 int i;
165
166 if (!groups)
167 return 0;
168
169 for (i = 0; groups[i]; i++) {
170 error = sysfs_create_group(kobj, groups[i]);
171 if (error) {
172 while (--i >= 0)
173 sysfs_remove_group(kobj, groups[i]);
174 break;
175 }
176 }
177 return error;
178}
179EXPORT_SYMBOL_GPL(sysfs_create_groups);
180
181/**
Robert P. J. Day1f8e1cd2011-05-07 17:18:20 -0400182 * sysfs_update_group - given a directory kobject, update an attribute group
183 * @kobj: The kobject to update the group on
184 * @grp: The attribute group to update
James Bottomley0f423892008-03-20 20:47:52 -0500185 *
186 * This function updates an attribute group. Unlike
187 * sysfs_create_group(), it will explicitly not warn or error if any
188 * of the attribute files being created already exist. Furthermore,
189 * if the visibility of the files has changed through the is_visible()
190 * callback, it will update the permissions and add or remove the
191 * relevant files.
192 *
193 * The primary use for this function is to call it after making a change
194 * that affects group visibility.
195 *
Antonio Ospiteed1dc8a82015-04-29 10:55:46 +0200196 * Returns 0 on success or error code on failure.
James Bottomley0f423892008-03-20 20:47:52 -0500197 */
198int sysfs_update_group(struct kobject *kobj,
199 const struct attribute_group *grp)
200{
201 return internal_create_group(kobj, 1, grp);
202}
Greg Kroah-Hartmand363bc52013-08-21 16:04:12 -0700203EXPORT_SYMBOL_GPL(sysfs_update_group);
James Bottomley0f423892008-03-20 20:47:52 -0500204
Greg Kroah-Hartmanf9ae4432013-08-21 16:12:34 -0700205/**
206 * sysfs_remove_group: remove a group from a kobject
207 * @kobj: kobject to remove the group from
208 * @grp: group to remove
209 *
210 * This function removes a group of attributes from a kobject. The attributes
211 * previously have to have been created for this group, otherwise it will fail.
212 */
Greg Kroah-Hartman995d8ed2013-08-21 16:07:29 -0700213void sysfs_remove_group(struct kobject *kobj,
214 const struct attribute_group *grp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215{
Tejun Heo324a56e2013-12-11 14:11:53 -0500216 struct kernfs_node *parent = kobj->sd;
217 struct kernfs_node *kn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218
James Morris057f6c02007-04-26 00:12:05 -0700219 if (grp->name) {
Tejun Heo324a56e2013-12-11 14:11:53 -0500220 kn = kernfs_find_and_get(parent, grp->name);
221 if (!kn) {
222 WARN(!kn, KERN_WARNING
Greg Kroah-Hartman16aebf12013-08-21 16:10:02 -0700223 "sysfs group %p not found for kobject '%s'\n",
224 grp, kobject_name(kobj));
Greg Kroah-Hartman969affd2008-02-07 11:58:54 -0500225 return;
226 }
Tejun Heoccf73cf2013-11-28 14:54:30 -0500227 } else {
Tejun Heo324a56e2013-12-11 14:11:53 -0500228 kn = parent;
229 kernfs_get(kn);
Tejun Heoccf73cf2013-11-28 14:54:30 -0500230 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231
Robert ABEL9f70a402014-05-05 15:17:20 +0200232 remove_files(kn, grp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233 if (grp->name)
Tejun Heo324a56e2013-12-11 14:11:53 -0500234 kernfs_remove(kn);
Tejun Heo608e2662007-06-14 04:27:22 +0900235
Tejun Heo324a56e2013-12-11 14:11:53 -0500236 kernfs_put(kn);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237}
Greg Kroah-Hartmand363bc52013-08-21 16:04:12 -0700238EXPORT_SYMBOL_GPL(sysfs_remove_group);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239
Alan Stern69d44ff2010-09-25 23:34:22 +0200240/**
Greg Kroah-Hartman3e9b2ba2013-08-21 13:47:50 -0700241 * sysfs_remove_groups - remove a list of groups
242 *
Greg Kroah-Hartmanf9ae4432013-08-21 16:12:34 -0700243 * @kobj: The kobject for the groups to be removed from
244 * @groups: NULL terminated list of groups to be removed
Greg Kroah-Hartman3e9b2ba2013-08-21 13:47:50 -0700245 *
Greg Kroah-Hartman09239ed2013-08-22 09:23:28 -0700246 * If groups is not NULL, remove the specified groups from the kobject.
Greg Kroah-Hartman3e9b2ba2013-08-21 13:47:50 -0700247 */
248void sysfs_remove_groups(struct kobject *kobj,
249 const struct attribute_group **groups)
250{
251 int i;
252
253 if (!groups)
254 return;
255 for (i = 0; groups[i]; i++)
256 sysfs_remove_group(kobj, groups[i]);
257}
258EXPORT_SYMBOL_GPL(sysfs_remove_groups);
259
260/**
Alan Stern69d44ff2010-09-25 23:34:22 +0200261 * sysfs_merge_group - merge files into a pre-existing attribute group.
262 * @kobj: The kobject containing the group.
263 * @grp: The files to create and the attribute group they belong to.
264 *
265 * This function returns an error if the group doesn't exist or any of the
266 * files already exist in that group, in which case none of the new files
267 * are created.
268 */
269int sysfs_merge_group(struct kobject *kobj,
270 const struct attribute_group *grp)
271{
Tejun Heo324a56e2013-12-11 14:11:53 -0500272 struct kernfs_node *parent;
Alan Stern69d44ff2010-09-25 23:34:22 +0200273 int error = 0;
274 struct attribute *const *attr;
275 int i;
276
Tejun Heo324a56e2013-12-11 14:11:53 -0500277 parent = kernfs_find_and_get(kobj->sd, grp->name);
278 if (!parent)
Alan Stern69d44ff2010-09-25 23:34:22 +0200279 return -ENOENT;
280
281 for ((i = 0, attr = grp->attrs); *attr && !error; (++i, ++attr))
Tejun Heo324a56e2013-12-11 14:11:53 -0500282 error = sysfs_add_file(parent, *attr, false);
Alan Stern69d44ff2010-09-25 23:34:22 +0200283 if (error) {
284 while (--i >= 0)
Tejun Heo324a56e2013-12-11 14:11:53 -0500285 kernfs_remove_by_name(parent, (*--attr)->name);
Alan Stern69d44ff2010-09-25 23:34:22 +0200286 }
Tejun Heo324a56e2013-12-11 14:11:53 -0500287 kernfs_put(parent);
Alan Stern69d44ff2010-09-25 23:34:22 +0200288
289 return error;
290}
291EXPORT_SYMBOL_GPL(sysfs_merge_group);
292
293/**
294 * sysfs_unmerge_group - remove files from a pre-existing attribute group.
295 * @kobj: The kobject containing the group.
296 * @grp: The files to remove and the attribute group they belong to.
297 */
298void sysfs_unmerge_group(struct kobject *kobj,
299 const struct attribute_group *grp)
300{
Tejun Heo324a56e2013-12-11 14:11:53 -0500301 struct kernfs_node *parent;
Alan Stern69d44ff2010-09-25 23:34:22 +0200302 struct attribute *const *attr;
303
Tejun Heo324a56e2013-12-11 14:11:53 -0500304 parent = kernfs_find_and_get(kobj->sd, grp->name);
305 if (parent) {
Alan Stern69d44ff2010-09-25 23:34:22 +0200306 for (attr = grp->attrs; *attr; ++attr)
Tejun Heo324a56e2013-12-11 14:11:53 -0500307 kernfs_remove_by_name(parent, (*attr)->name);
308 kernfs_put(parent);
Alan Stern69d44ff2010-09-25 23:34:22 +0200309 }
310}
311EXPORT_SYMBOL_GPL(sysfs_unmerge_group);
312
Rafael J. Wysocki0bb8f3d2013-01-25 21:51:13 +0100313/**
314 * sysfs_add_link_to_group - add a symlink to an attribute group.
315 * @kobj: The kobject containing the group.
316 * @group_name: The name of the group.
317 * @target: The target kobject of the symlink to create.
318 * @link_name: The name of the symlink to create.
319 */
320int sysfs_add_link_to_group(struct kobject *kobj, const char *group_name,
321 struct kobject *target, const char *link_name)
322{
Tejun Heo324a56e2013-12-11 14:11:53 -0500323 struct kernfs_node *parent;
Rafael J. Wysocki0bb8f3d2013-01-25 21:51:13 +0100324 int error = 0;
325
Tejun Heo324a56e2013-12-11 14:11:53 -0500326 parent = kernfs_find_and_get(kobj->sd, group_name);
327 if (!parent)
Rafael J. Wysocki0bb8f3d2013-01-25 21:51:13 +0100328 return -ENOENT;
329
Tejun Heo324a56e2013-12-11 14:11:53 -0500330 error = sysfs_create_link_sd(parent, target, link_name);
331 kernfs_put(parent);
Rafael J. Wysocki0bb8f3d2013-01-25 21:51:13 +0100332
333 return error;
334}
335EXPORT_SYMBOL_GPL(sysfs_add_link_to_group);
336
337/**
338 * sysfs_remove_link_from_group - remove a symlink from an attribute group.
339 * @kobj: The kobject containing the group.
340 * @group_name: The name of the group.
341 * @link_name: The name of the symlink to remove.
342 */
343void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name,
344 const char *link_name)
345{
Tejun Heo324a56e2013-12-11 14:11:53 -0500346 struct kernfs_node *parent;
Rafael J. Wysocki0bb8f3d2013-01-25 21:51:13 +0100347
Tejun Heo324a56e2013-12-11 14:11:53 -0500348 parent = kernfs_find_and_get(kobj->sd, group_name);
349 if (parent) {
350 kernfs_remove_by_name(parent, link_name);
351 kernfs_put(parent);
Rafael J. Wysocki0bb8f3d2013-01-25 21:51:13 +0100352 }
353}
354EXPORT_SYMBOL_GPL(sysfs_remove_link_from_group);