blob: 09a1a25cd14540c77d0713b7d1ecd381f78c4886 [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
6 *
7 * This file is released undert the GPL v2.
8 *
9 */
10
11#include <linux/kobject.h>
12#include <linux/module.h>
13#include <linux/dcache.h>
Christoph Hellwig5f45f1a2005-06-23 00:09:12 -070014#include <linux/namei.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070015#include <linux/err.h>
16#include "sysfs.h"
17
18
James Bottomleyd4acd722007-10-31 09:38:04 -050019static void remove_files(struct sysfs_dirent *dir_sd, struct kobject *kobj,
Tejun Heo608e2662007-06-14 04:27:22 +090020 const struct attribute_group *grp)
Linus Torvalds1da177e2005-04-16 15:20:36 -070021{
22 struct attribute *const* attr;
Greg Kroah-Hartman6ab9cea2013-07-14 16:05:55 -070023 struct bin_attribute *const* bin_attr;
Linus Torvalds1da177e2005-04-16 15:20:36 -070024
Greg Kroah-Hartman6ab9cea2013-07-14 16:05:55 -070025 if (grp->attrs)
26 for (attr = grp->attrs; *attr; attr++)
27 sysfs_hash_and_remove(dir_sd, NULL, (*attr)->name);
28 if (grp->bin_attrs)
29 for (bin_attr = grp->bin_attrs; *bin_attr; bin_attr++)
30 sysfs_remove_bin_file(kobj, *bin_attr);
Linus Torvalds1da177e2005-04-16 15:20:36 -070031}
32
James Bottomleyd4acd722007-10-31 09:38:04 -050033static int create_files(struct sysfs_dirent *dir_sd, struct kobject *kobj,
James Bottomley0f423892008-03-20 20:47:52 -050034 const struct attribute_group *grp, int update)
Linus Torvalds1da177e2005-04-16 15:20:36 -070035{
36 struct attribute *const* attr;
Greg Kroah-Hartman6ab9cea2013-07-14 16:05:55 -070037 struct bin_attribute *const* bin_attr;
James Bottomleyd4acd722007-10-31 09:38:04 -050038 int error = 0, i;
Linus Torvalds1da177e2005-04-16 15:20:36 -070039
Greg Kroah-Hartman6ab9cea2013-07-14 16:05:55 -070040 if (grp->attrs) {
41 for (i = 0, attr = grp->attrs; *attr && !error; i++, attr++) {
42 umode_t mode = 0;
James Bottomley0f423892008-03-20 20:47:52 -050043
Greg Kroah-Hartman6ab9cea2013-07-14 16:05:55 -070044 /*
45 * In update mode, we're changing the permissions or
46 * visibility. Do this by first removing then
47 * re-adding (if required) the file.
48 */
49 if (update)
50 sysfs_hash_and_remove(dir_sd, NULL,
51 (*attr)->name);
52 if (grp->is_visible) {
53 mode = grp->is_visible(kobj, *attr, i);
54 if (!mode)
55 continue;
56 }
57 error = sysfs_add_file_mode(dir_sd, *attr,
58 SYSFS_KOBJ_ATTR,
59 (*attr)->mode | mode);
60 if (unlikely(error))
61 break;
James Bottomley0f423892008-03-20 20:47:52 -050062 }
Greg Kroah-Hartman6ab9cea2013-07-14 16:05:55 -070063 if (error) {
64 remove_files(dir_sd, kobj, grp);
65 goto exit;
66 }
James Bottomley0f423892008-03-20 20:47:52 -050067 }
Greg Kroah-Hartman6ab9cea2013-07-14 16:05:55 -070068
69 if (grp->bin_attrs) {
70 for (bin_attr = grp->bin_attrs; *bin_attr; bin_attr++) {
71 if (update)
72 sysfs_remove_bin_file(kobj, *bin_attr);
73 error = sysfs_create_bin_file(kobj, *bin_attr);
74 if (error)
75 break;
76 }
77 if (error)
78 remove_files(dir_sd, kobj, grp);
79 }
80exit:
Linus Torvalds1da177e2005-04-16 15:20:36 -070081 return error;
82}
83
84
James Bottomley0f423892008-03-20 20:47:52 -050085static int internal_create_group(struct kobject *kobj, int update,
86 const struct attribute_group *grp)
Linus Torvalds1da177e2005-04-16 15:20:36 -070087{
Tejun Heo608e2662007-06-14 04:27:22 +090088 struct sysfs_dirent *sd;
Linus Torvalds1da177e2005-04-16 15:20:36 -070089 int error;
90
James Bottomley0f423892008-03-20 20:47:52 -050091 BUG_ON(!kobj || (!update && !kobj->sd));
92
93 /* Updates may happen before the object has been instantiated */
94 if (unlikely(update && !kobj->sd))
95 return -EINVAL;
Oliver Schinagl388a8c32013-07-14 16:05:56 -070096 if (!grp->attrs && !grp->bin_attrs) {
97 WARN(1, "sysfs: (bin_)attrs not set by subsystem for group: %s/%s\n",
Bruno Prémont5631f2c2012-04-03 09:59:48 +020098 kobj->name, grp->name ? "" : grp->name);
99 return -EINVAL;
100 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101 if (grp->name) {
Tejun Heo608e2662007-06-14 04:27:22 +0900102 error = sysfs_create_subdir(kobj, grp->name, &sd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103 if (error)
104 return error;
105 } else
Tejun Heo608e2662007-06-14 04:27:22 +0900106 sd = kobj->sd;
107 sysfs_get(sd);
James Bottomley0f423892008-03-20 20:47:52 -0500108 error = create_files(sd, kobj, grp, update);
Tejun Heo608e2662007-06-14 04:27:22 +0900109 if (error) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110 if (grp->name)
Tejun Heo608e2662007-06-14 04:27:22 +0900111 sysfs_remove_subdir(sd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112 }
Tejun Heo608e2662007-06-14 04:27:22 +0900113 sysfs_put(sd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114 return error;
115}
116
James Bottomley0f423892008-03-20 20:47:52 -0500117/**
118 * sysfs_create_group - given a directory kobject, create an attribute group
119 * @kobj: The kobject to create the group on
120 * @grp: The attribute group to create
121 *
122 * This function creates a group for the first time. It will explicitly
123 * warn and error if any of the attribute files being created already exist.
124 *
125 * Returns 0 on success or error.
126 */
127int sysfs_create_group(struct kobject *kobj,
128 const struct attribute_group *grp)
129{
130 return internal_create_group(kobj, 0, grp);
131}
132
133/**
Robert P. J. Day1f8e1cd2011-05-07 17:18:20 -0400134 * sysfs_update_group - given a directory kobject, update an attribute group
135 * @kobj: The kobject to update the group on
136 * @grp: The attribute group to update
James Bottomley0f423892008-03-20 20:47:52 -0500137 *
138 * This function updates an attribute group. Unlike
139 * sysfs_create_group(), it will explicitly not warn or error if any
140 * of the attribute files being created already exist. Furthermore,
141 * if the visibility of the files has changed through the is_visible()
142 * callback, it will update the permissions and add or remove the
143 * relevant files.
144 *
145 * The primary use for this function is to call it after making a change
146 * that affects group visibility.
147 *
148 * Returns 0 on success or error.
149 */
150int sysfs_update_group(struct kobject *kobj,
151 const struct attribute_group *grp)
152{
153 return internal_create_group(kobj, 1, grp);
154}
155
156
157
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158void sysfs_remove_group(struct kobject * kobj,
159 const struct attribute_group * grp)
160{
Tejun Heo608e2662007-06-14 04:27:22 +0900161 struct sysfs_dirent *dir_sd = kobj->sd;
162 struct sysfs_dirent *sd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163
James Morris057f6c02007-04-26 00:12:05 -0700164 if (grp->name) {
Eric W. Biederman3ff195b2010-03-30 11:31:26 -0700165 sd = sysfs_get_dirent(dir_sd, NULL, grp->name);
Greg Kroah-Hartman969affd2008-02-07 11:58:54 -0500166 if (!sd) {
Arjan van de Ven99fcd772008-07-25 19:45:41 -0700167 WARN(!sd, KERN_WARNING "sysfs group %p not found for "
Greg Kroah-Hartman969affd2008-02-07 11:58:54 -0500168 "kobject '%s'\n", grp, kobject_name(kobj));
Greg Kroah-Hartman969affd2008-02-07 11:58:54 -0500169 return;
170 }
Tejun Heo608e2662007-06-14 04:27:22 +0900171 } else
172 sd = sysfs_get(dir_sd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173
James Bottomleyd4acd722007-10-31 09:38:04 -0500174 remove_files(sd, kobj, grp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700175 if (grp->name)
Tejun Heo608e2662007-06-14 04:27:22 +0900176 sysfs_remove_subdir(sd);
177
178 sysfs_put(sd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179}
180
Alan Stern69d44ff2010-09-25 23:34:22 +0200181/**
182 * sysfs_merge_group - merge files into a pre-existing attribute group.
183 * @kobj: The kobject containing the group.
184 * @grp: The files to create and the attribute group they belong to.
185 *
186 * This function returns an error if the group doesn't exist or any of the
187 * files already exist in that group, in which case none of the new files
188 * are created.
189 */
190int sysfs_merge_group(struct kobject *kobj,
191 const struct attribute_group *grp)
192{
193 struct sysfs_dirent *dir_sd;
194 int error = 0;
195 struct attribute *const *attr;
196 int i;
197
Alan Sterne030d582010-11-15 15:46:07 -0500198 dir_sd = sysfs_get_dirent(kobj->sd, NULL, grp->name);
Alan Stern69d44ff2010-09-25 23:34:22 +0200199 if (!dir_sd)
200 return -ENOENT;
201
202 for ((i = 0, attr = grp->attrs); *attr && !error; (++i, ++attr))
203 error = sysfs_add_file(dir_sd, *attr, SYSFS_KOBJ_ATTR);
204 if (error) {
205 while (--i >= 0)
206 sysfs_hash_and_remove(dir_sd, NULL, (*--attr)->name);
207 }
208 sysfs_put(dir_sd);
209
210 return error;
211}
212EXPORT_SYMBOL_GPL(sysfs_merge_group);
213
214/**
215 * sysfs_unmerge_group - remove files from a pre-existing attribute group.
216 * @kobj: The kobject containing the group.
217 * @grp: The files to remove and the attribute group they belong to.
218 */
219void sysfs_unmerge_group(struct kobject *kobj,
220 const struct attribute_group *grp)
221{
222 struct sysfs_dirent *dir_sd;
223 struct attribute *const *attr;
224
Alan Sterne030d582010-11-15 15:46:07 -0500225 dir_sd = sysfs_get_dirent(kobj->sd, NULL, grp->name);
Alan Stern69d44ff2010-09-25 23:34:22 +0200226 if (dir_sd) {
227 for (attr = grp->attrs; *attr; ++attr)
228 sysfs_hash_and_remove(dir_sd, NULL, (*attr)->name);
229 sysfs_put(dir_sd);
230 }
231}
232EXPORT_SYMBOL_GPL(sysfs_unmerge_group);
233
Rafael J. Wysocki0bb8f3d2013-01-25 21:51:13 +0100234/**
235 * sysfs_add_link_to_group - add a symlink to an attribute group.
236 * @kobj: The kobject containing the group.
237 * @group_name: The name of the group.
238 * @target: The target kobject of the symlink to create.
239 * @link_name: The name of the symlink to create.
240 */
241int sysfs_add_link_to_group(struct kobject *kobj, const char *group_name,
242 struct kobject *target, const char *link_name)
243{
244 struct sysfs_dirent *dir_sd;
245 int error = 0;
246
247 dir_sd = sysfs_get_dirent(kobj->sd, NULL, group_name);
248 if (!dir_sd)
249 return -ENOENT;
250
251 error = sysfs_create_link_sd(dir_sd, target, link_name);
252 sysfs_put(dir_sd);
253
254 return error;
255}
256EXPORT_SYMBOL_GPL(sysfs_add_link_to_group);
257
258/**
259 * sysfs_remove_link_from_group - remove a symlink from an attribute group.
260 * @kobj: The kobject containing the group.
261 * @group_name: The name of the group.
262 * @link_name: The name of the symlink to remove.
263 */
264void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name,
265 const char *link_name)
266{
267 struct sysfs_dirent *dir_sd;
268
269 dir_sd = sysfs_get_dirent(kobj->sd, NULL, group_name);
270 if (dir_sd) {
271 sysfs_hash_and_remove(dir_sd, NULL, link_name);
272 sysfs_put(dir_sd);
273 }
274}
275EXPORT_SYMBOL_GPL(sysfs_remove_link_from_group);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276
277EXPORT_SYMBOL_GPL(sysfs_create_group);
James Bottomley0f423892008-03-20 20:47:52 -0500278EXPORT_SYMBOL_GPL(sysfs_update_group);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279EXPORT_SYMBOL_GPL(sysfs_remove_group);