Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
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 | |
9e2a47ed GKH |
6 | * Copyright (c) 2013 Greg Kroah-Hartman |
7 | * Copyright (c) 2013 The Linux Foundation | |
1da177e4 | 8 | * |
e6c56920 | 9 | * This file is released undert the GPL v2. |
1da177e4 LT |
10 | * |
11 | */ | |
12 | ||
13 | #include <linux/kobject.h> | |
14 | #include <linux/module.h> | |
15 | #include <linux/dcache.h> | |
5f45f1a7 | 16 | #include <linux/namei.h> |
1da177e4 LT |
17 | #include <linux/err.h> |
18 | #include "sysfs.h" | |
19 | ||
20 | ||
d4acd722 | 21 | static void remove_files(struct sysfs_dirent *dir_sd, struct kobject *kobj, |
608e266a | 22 | const struct attribute_group *grp) |
1da177e4 | 23 | { |
995d8ed9 GKH |
24 | struct attribute *const *attr; |
25 | struct bin_attribute *const *bin_attr; | |
1da177e4 | 26 | |
6ab9cea1 GKH |
27 | if (grp->attrs) |
28 | for (attr = grp->attrs; *attr; attr++) | |
29 | sysfs_hash_and_remove(dir_sd, NULL, (*attr)->name); | |
30 | if (grp->bin_attrs) | |
31 | for (bin_attr = grp->bin_attrs; *bin_attr; bin_attr++) | |
32 | sysfs_remove_bin_file(kobj, *bin_attr); | |
1da177e4 LT |
33 | } |
34 | ||
d4acd722 | 35 | static int create_files(struct sysfs_dirent *dir_sd, struct kobject *kobj, |
0f423895 | 36 | const struct attribute_group *grp, int update) |
1da177e4 | 37 | { |
995d8ed9 GKH |
38 | struct attribute *const *attr; |
39 | struct bin_attribute *const *bin_attr; | |
d4acd722 | 40 | int error = 0, i; |
1da177e4 | 41 | |
6ab9cea1 GKH |
42 | if (grp->attrs) { |
43 | for (i = 0, attr = grp->attrs; *attr && !error; i++, attr++) { | |
44 | umode_t mode = 0; | |
0f423895 | 45 | |
6ab9cea1 GKH |
46 | /* |
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) | |
52 | sysfs_hash_and_remove(dir_sd, NULL, | |
53 | (*attr)->name); | |
54 | if (grp->is_visible) { | |
55 | mode = grp->is_visible(kobj, *attr, i); | |
56 | if (!mode) | |
57 | continue; | |
58 | } | |
58292cbe TH |
59 | error = sysfs_add_file_mode_ns(dir_sd, *attr, |
60 | SYSFS_KOBJ_ATTR, | |
61 | (*attr)->mode | mode, | |
62 | NULL); | |
6ab9cea1 GKH |
63 | if (unlikely(error)) |
64 | break; | |
65 | } | |
66 | if (error) { | |
67 | remove_files(dir_sd, kobj, grp); | |
68 | goto exit; | |
69 | } | |
70 | } | |
71 | ||
72 | if (grp->bin_attrs) { | |
73 | for (bin_attr = grp->bin_attrs; *bin_attr; bin_attr++) { | |
74 | if (update) | |
75 | sysfs_remove_bin_file(kobj, *bin_attr); | |
76 | error = sysfs_create_bin_file(kobj, *bin_attr); | |
77 | if (error) | |
78 | break; | |
0f423895 | 79 | } |
6ab9cea1 GKH |
80 | if (error) |
81 | remove_files(dir_sd, kobj, grp); | |
0f423895 | 82 | } |
6ab9cea1 | 83 | exit: |
1da177e4 LT |
84 | return error; |
85 | } | |
86 | ||
87 | ||
0f423895 JB |
88 | static int internal_create_group(struct kobject *kobj, int update, |
89 | const struct attribute_group *grp) | |
1da177e4 | 90 | { |
608e266a | 91 | struct sysfs_dirent *sd; |
1da177e4 LT |
92 | int error; |
93 | ||
0f423895 JB |
94 | BUG_ON(!kobj || (!update && !kobj->sd)); |
95 | ||
96 | /* Updates may happen before the object has been instantiated */ | |
97 | if (unlikely(update && !kobj->sd)) | |
98 | return -EINVAL; | |
388a8c35 OS |
99 | if (!grp->attrs && !grp->bin_attrs) { |
100 | WARN(1, "sysfs: (bin_)attrs not set by subsystem for group: %s/%s\n", | |
5631f2c1 BP |
101 | kobj->name, grp->name ? "" : grp->name); |
102 | return -EINVAL; | |
103 | } | |
1da177e4 | 104 | if (grp->name) { |
608e266a | 105 | error = sysfs_create_subdir(kobj, grp->name, &sd); |
1da177e4 LT |
106 | if (error) |
107 | return error; | |
108 | } else | |
608e266a TH |
109 | sd = kobj->sd; |
110 | sysfs_get(sd); | |
0f423895 | 111 | error = create_files(sd, kobj, grp, update); |
608e266a | 112 | if (error) { |
1da177e4 | 113 | if (grp->name) |
608e266a | 114 | sysfs_remove_subdir(sd); |
1da177e4 | 115 | } |
608e266a | 116 | sysfs_put(sd); |
1da177e4 LT |
117 | return error; |
118 | } | |
119 | ||
0f423895 JB |
120 | /** |
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 | |
124 | * | |
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. | |
127 | * | |
128 | * Returns 0 on success or error. | |
129 | */ | |
130 | int sysfs_create_group(struct kobject *kobj, | |
131 | const struct attribute_group *grp) | |
132 | { | |
133 | return internal_create_group(kobj, 0, grp); | |
134 | } | |
d363bc53 | 135 | EXPORT_SYMBOL_GPL(sysfs_create_group); |
0f423895 | 136 | |
3e9b2bae GKH |
137 | /** |
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 | |
141 | * | |
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. | |
147 | * | |
09239ed4 | 148 | * Returns 0 on success or error code from sysfs_create_group on error. |
3e9b2bae GKH |
149 | */ |
150 | int sysfs_create_groups(struct kobject *kobj, | |
151 | const struct attribute_group **groups) | |
152 | { | |
153 | int error = 0; | |
154 | int i; | |
155 | ||
156 | if (!groups) | |
157 | return 0; | |
158 | ||
159 | for (i = 0; groups[i]; i++) { | |
160 | error = sysfs_create_group(kobj, groups[i]); | |
161 | if (error) { | |
162 | while (--i >= 0) | |
163 | sysfs_remove_group(kobj, groups[i]); | |
164 | break; | |
165 | } | |
166 | } | |
167 | return error; | |
168 | } | |
169 | EXPORT_SYMBOL_GPL(sysfs_create_groups); | |
170 | ||
0f423895 | 171 | /** |
1f8e1cda RD |
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 | |
0f423895 JB |
175 | * |
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 | |
181 | * relevant files. | |
182 | * | |
183 | * The primary use for this function is to call it after making a change | |
184 | * that affects group visibility. | |
185 | * | |
186 | * Returns 0 on success or error. | |
187 | */ | |
188 | int sysfs_update_group(struct kobject *kobj, | |
189 | const struct attribute_group *grp) | |
190 | { | |
191 | return internal_create_group(kobj, 1, grp); | |
192 | } | |
d363bc53 | 193 | EXPORT_SYMBOL_GPL(sysfs_update_group); |
0f423895 | 194 | |
f9ae443b GKH |
195 | /** |
196 | * sysfs_remove_group: remove a group from a kobject | |
197 | * @kobj: kobject to remove the group from | |
198 | * @grp: group to remove | |
199 | * | |
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. | |
202 | */ | |
995d8ed9 GKH |
203 | void sysfs_remove_group(struct kobject *kobj, |
204 | const struct attribute_group *grp) | |
1da177e4 | 205 | { |
608e266a TH |
206 | struct sysfs_dirent *dir_sd = kobj->sd; |
207 | struct sysfs_dirent *sd; | |
1da177e4 | 208 | |
057f6c01 | 209 | if (grp->name) { |
388975cc | 210 | sd = sysfs_get_dirent(dir_sd, grp->name); |
969affd2 | 211 | if (!sd) { |
16aebf1c GKH |
212 | WARN(!sd, KERN_WARNING |
213 | "sysfs group %p not found for kobject '%s'\n", | |
214 | grp, kobject_name(kobj)); | |
969affd2 GKH |
215 | return; |
216 | } | |
608e266a TH |
217 | } else |
218 | sd = sysfs_get(dir_sd); | |
1da177e4 | 219 | |
d4acd722 | 220 | remove_files(sd, kobj, grp); |
1da177e4 | 221 | if (grp->name) |
608e266a TH |
222 | sysfs_remove_subdir(sd); |
223 | ||
224 | sysfs_put(sd); | |
1da177e4 | 225 | } |
d363bc53 | 226 | EXPORT_SYMBOL_GPL(sysfs_remove_group); |
1da177e4 | 227 | |
3e9b2bae GKH |
228 | /** |
229 | * sysfs_remove_groups - remove a list of groups | |
230 | * | |
f9ae443b GKH |
231 | * @kobj: The kobject for the groups to be removed from |
232 | * @groups: NULL terminated list of groups to be removed | |
3e9b2bae | 233 | * |
09239ed4 | 234 | * If groups is not NULL, remove the specified groups from the kobject. |
3e9b2bae GKH |
235 | */ |
236 | void sysfs_remove_groups(struct kobject *kobj, | |
237 | const struct attribute_group **groups) | |
238 | { | |
239 | int i; | |
240 | ||
241 | if (!groups) | |
242 | return; | |
243 | for (i = 0; groups[i]; i++) | |
244 | sysfs_remove_group(kobj, groups[i]); | |
245 | } | |
246 | EXPORT_SYMBOL_GPL(sysfs_remove_groups); | |
247 | ||
69d44ffb AS |
248 | /** |
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. | |
252 | * | |
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 | |
255 | * are created. | |
256 | */ | |
257 | int sysfs_merge_group(struct kobject *kobj, | |
258 | const struct attribute_group *grp) | |
259 | { | |
260 | struct sysfs_dirent *dir_sd; | |
261 | int error = 0; | |
262 | struct attribute *const *attr; | |
263 | int i; | |
264 | ||
388975cc | 265 | dir_sd = sysfs_get_dirent(kobj->sd, grp->name); |
69d44ffb AS |
266 | if (!dir_sd) |
267 | return -ENOENT; | |
268 | ||
269 | for ((i = 0, attr = grp->attrs); *attr && !error; (++i, ++attr)) | |
270 | error = sysfs_add_file(dir_sd, *attr, SYSFS_KOBJ_ATTR); | |
271 | if (error) { | |
272 | while (--i >= 0) | |
273 | sysfs_hash_and_remove(dir_sd, NULL, (*--attr)->name); | |
274 | } | |
275 | sysfs_put(dir_sd); | |
276 | ||
277 | return error; | |
278 | } | |
279 | EXPORT_SYMBOL_GPL(sysfs_merge_group); | |
280 | ||
281 | /** | |
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. | |
285 | */ | |
286 | void sysfs_unmerge_group(struct kobject *kobj, | |
287 | const struct attribute_group *grp) | |
288 | { | |
289 | struct sysfs_dirent *dir_sd; | |
290 | struct attribute *const *attr; | |
291 | ||
388975cc | 292 | dir_sd = sysfs_get_dirent(kobj->sd, grp->name); |
69d44ffb AS |
293 | if (dir_sd) { |
294 | for (attr = grp->attrs; *attr; ++attr) | |
295 | sysfs_hash_and_remove(dir_sd, NULL, (*attr)->name); | |
296 | sysfs_put(dir_sd); | |
297 | } | |
298 | } | |
299 | EXPORT_SYMBOL_GPL(sysfs_unmerge_group); | |
300 | ||
0bb8f3d6 RW |
301 | /** |
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. | |
307 | */ | |
308 | int sysfs_add_link_to_group(struct kobject *kobj, const char *group_name, | |
309 | struct kobject *target, const char *link_name) | |
310 | { | |
311 | struct sysfs_dirent *dir_sd; | |
312 | int error = 0; | |
313 | ||
388975cc | 314 | dir_sd = sysfs_get_dirent(kobj->sd, group_name); |
0bb8f3d6 RW |
315 | if (!dir_sd) |
316 | return -ENOENT; | |
317 | ||
318 | error = sysfs_create_link_sd(dir_sd, target, link_name); | |
319 | sysfs_put(dir_sd); | |
320 | ||
321 | return error; | |
322 | } | |
323 | EXPORT_SYMBOL_GPL(sysfs_add_link_to_group); | |
324 | ||
325 | /** | |
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. | |
330 | */ | |
331 | void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name, | |
332 | const char *link_name) | |
333 | { | |
334 | struct sysfs_dirent *dir_sd; | |
335 | ||
388975cc | 336 | dir_sd = sysfs_get_dirent(kobj->sd, group_name); |
0bb8f3d6 RW |
337 | if (dir_sd) { |
338 | sysfs_hash_and_remove(dir_sd, NULL, link_name); | |
339 | sysfs_put(dir_sd); | |
340 | } | |
341 | } | |
342 | EXPORT_SYMBOL_GPL(sysfs_remove_link_from_group); |