2 * fs/sysfs/group.c - Operations for adding/removing multiple files at once.
4 * Copyright (c) 2003 Patrick Mochel
5 * Copyright (c) 2003 Open Source Development Lab
6 * Copyright (c) 2013 Greg Kroah-Hartman
7 * Copyright (c) 2013 The Linux Foundation
9 * This file is released undert the GPL v2.
13 #include <linux/kobject.h>
14 #include <linux/module.h>
15 #include <linux/dcache.h>
16 #include <linux/namei.h>
17 #include <linux/err.h>
21 static void remove_files(struct sysfs_dirent
*dir_sd
, struct kobject
*kobj
,
22 const struct attribute_group
*grp
)
24 struct attribute
*const *attr
;
25 struct bin_attribute
*const *bin_attr
;
28 for (attr
= grp
->attrs
; *attr
; attr
++)
29 sysfs_hash_and_remove(dir_sd
, (*attr
)->name
, NULL
);
31 for (bin_attr
= grp
->bin_attrs
; *bin_attr
; bin_attr
++)
32 sysfs_remove_bin_file(kobj
, *bin_attr
);
35 static int create_files(struct sysfs_dirent
*dir_sd
, struct kobject
*kobj
,
36 const struct attribute_group
*grp
, int update
)
38 struct attribute
*const *attr
;
39 struct bin_attribute
*const *bin_attr
;
43 for (i
= 0, attr
= grp
->attrs
; *attr
&& !error
; i
++, attr
++) {
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.
52 sysfs_hash_and_remove(dir_sd
, (*attr
)->name
,
54 if (grp
->is_visible
) {
55 mode
= grp
->is_visible(kobj
, *attr
, i
);
59 error
= sysfs_add_file_mode_ns(dir_sd
, *attr
,
67 remove_files(dir_sd
, kobj
, grp
);
73 for (bin_attr
= grp
->bin_attrs
; *bin_attr
; bin_attr
++) {
75 sysfs_remove_bin_file(kobj
, *bin_attr
);
76 error
= sysfs_create_bin_file(kobj
, *bin_attr
);
81 remove_files(dir_sd
, kobj
, grp
);
88 static int internal_create_group(struct kobject
*kobj
, int update
,
89 const struct attribute_group
*grp
)
91 struct sysfs_dirent
*sd
;
94 BUG_ON(!kobj
|| (!update
&& !kobj
->sd
));
96 /* Updates may happen before the object has been instantiated */
97 if (unlikely(update
&& !kobj
->sd
))
99 if (!grp
->attrs
&& !grp
->bin_attrs
) {
100 WARN(1, "sysfs: (bin_)attrs not set by subsystem for group: %s/%s\n",
101 kobj
->name
, grp
->name
? "" : grp
->name
);
105 error
= sysfs_create_subdir(kobj
, grp
->name
, &sd
);
111 error
= create_files(sd
, kobj
, grp
, update
);
121 * sysfs_create_group - given a directory kobject, create an attribute group
122 * @kobj: The kobject to create the group on
123 * @grp: The attribute group to create
125 * This function creates a group for the first time. It will explicitly
126 * warn and error if any of the attribute files being created already exist.
128 * Returns 0 on success or error.
130 int sysfs_create_group(struct kobject
*kobj
,
131 const struct attribute_group
*grp
)
133 return internal_create_group(kobj
, 0, grp
);
135 EXPORT_SYMBOL_GPL(sysfs_create_group
);
138 * sysfs_create_groups - given a directory kobject, create a bunch of attribute groups
139 * @kobj: The kobject to create the group on
140 * @groups: The attribute groups to create, NULL terminated
142 * This function creates a bunch of attribute groups. If an error occurs when
143 * creating a group, all previously created groups will be removed, unwinding
144 * everything back to the original state when this function was called.
145 * It will explicitly warn and error if any of the attribute files being
146 * created already exist.
148 * Returns 0 on success or error code from sysfs_create_group on error.
150 int sysfs_create_groups(struct kobject
*kobj
,
151 const struct attribute_group
**groups
)
159 for (i
= 0; groups
[i
]; i
++) {
160 error
= sysfs_create_group(kobj
, groups
[i
]);
163 sysfs_remove_group(kobj
, groups
[i
]);
169 EXPORT_SYMBOL_GPL(sysfs_create_groups
);
172 * sysfs_update_group - given a directory kobject, update an attribute group
173 * @kobj: The kobject to update the group on
174 * @grp: The attribute group to update
176 * This function updates an attribute group. Unlike
177 * sysfs_create_group(), it will explicitly not warn or error if any
178 * of the attribute files being created already exist. Furthermore,
179 * if the visibility of the files has changed through the is_visible()
180 * callback, it will update the permissions and add or remove the
183 * The primary use for this function is to call it after making a change
184 * that affects group visibility.
186 * Returns 0 on success or error.
188 int sysfs_update_group(struct kobject
*kobj
,
189 const struct attribute_group
*grp
)
191 return internal_create_group(kobj
, 1, grp
);
193 EXPORT_SYMBOL_GPL(sysfs_update_group
);
196 * sysfs_remove_group: remove a group from a kobject
197 * @kobj: kobject to remove the group from
198 * @grp: group to remove
200 * This function removes a group of attributes from a kobject. The attributes
201 * previously have to have been created for this group, otherwise it will fail.
203 void sysfs_remove_group(struct kobject
*kobj
,
204 const struct attribute_group
*grp
)
206 struct sysfs_dirent
*dir_sd
= kobj
->sd
;
207 struct sysfs_dirent
*sd
;
210 sd
= sysfs_get_dirent(dir_sd
, grp
->name
);
212 WARN(!sd
, KERN_WARNING
213 "sysfs group %p not found for kobject '%s'\n",
214 grp
, kobject_name(kobj
));
218 sd
= sysfs_get(dir_sd
);
220 remove_files(sd
, kobj
, grp
);
226 EXPORT_SYMBOL_GPL(sysfs_remove_group
);
229 * sysfs_remove_groups - remove a list of groups
231 * @kobj: The kobject for the groups to be removed from
232 * @groups: NULL terminated list of groups to be removed
234 * If groups is not NULL, remove the specified groups from the kobject.
236 void sysfs_remove_groups(struct kobject
*kobj
,
237 const struct attribute_group
**groups
)
243 for (i
= 0; groups
[i
]; i
++)
244 sysfs_remove_group(kobj
, groups
[i
]);
246 EXPORT_SYMBOL_GPL(sysfs_remove_groups
);
249 * sysfs_merge_group - merge files into a pre-existing attribute group.
250 * @kobj: The kobject containing the group.
251 * @grp: The files to create and the attribute group they belong to.
253 * This function returns an error if the group doesn't exist or any of the
254 * files already exist in that group, in which case none of the new files
257 int sysfs_merge_group(struct kobject
*kobj
,
258 const struct attribute_group
*grp
)
260 struct sysfs_dirent
*dir_sd
;
262 struct attribute
*const *attr
;
265 dir_sd
= sysfs_get_dirent(kobj
->sd
, grp
->name
);
269 for ((i
= 0, attr
= grp
->attrs
); *attr
&& !error
; (++i
, ++attr
))
270 error
= sysfs_add_file(dir_sd
, *attr
, SYSFS_KOBJ_ATTR
);
273 sysfs_hash_and_remove(dir_sd
, (*--attr
)->name
, NULL
);
279 EXPORT_SYMBOL_GPL(sysfs_merge_group
);
282 * sysfs_unmerge_group - remove files from a pre-existing attribute group.
283 * @kobj: The kobject containing the group.
284 * @grp: The files to remove and the attribute group they belong to.
286 void sysfs_unmerge_group(struct kobject
*kobj
,
287 const struct attribute_group
*grp
)
289 struct sysfs_dirent
*dir_sd
;
290 struct attribute
*const *attr
;
292 dir_sd
= sysfs_get_dirent(kobj
->sd
, grp
->name
);
294 for (attr
= grp
->attrs
; *attr
; ++attr
)
295 sysfs_hash_and_remove(dir_sd
, (*attr
)->name
, NULL
);
299 EXPORT_SYMBOL_GPL(sysfs_unmerge_group
);
302 * sysfs_add_link_to_group - add a symlink to an attribute group.
303 * @kobj: The kobject containing the group.
304 * @group_name: The name of the group.
305 * @target: The target kobject of the symlink to create.
306 * @link_name: The name of the symlink to create.
308 int sysfs_add_link_to_group(struct kobject
*kobj
, const char *group_name
,
309 struct kobject
*target
, const char *link_name
)
311 struct sysfs_dirent
*dir_sd
;
314 dir_sd
= sysfs_get_dirent(kobj
->sd
, group_name
);
318 error
= sysfs_create_link_sd(dir_sd
, target
, link_name
);
323 EXPORT_SYMBOL_GPL(sysfs_add_link_to_group
);
326 * sysfs_remove_link_from_group - remove a symlink from an attribute group.
327 * @kobj: The kobject containing the group.
328 * @group_name: The name of the group.
329 * @link_name: The name of the symlink to remove.
331 void sysfs_remove_link_from_group(struct kobject
*kobj
, const char *group_name
,
332 const char *link_name
)
334 struct sysfs_dirent
*dir_sd
;
336 dir_sd
= sysfs_get_dirent(kobj
->sd
, group_name
);
338 sysfs_hash_and_remove(dir_sd
, link_name
, NULL
);
342 EXPORT_SYMBOL_GPL(sysfs_remove_link_from_group
);