Commit | Line | Data |
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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 | } | |
59 | error = sysfs_add_file_mode(dir_sd, *attr, | |
60 | SYSFS_KOBJ_ATTR, | |
61 | (*attr)->mode | mode); | |
62 | if (unlikely(error)) | |
63 | break; | |
64 | } | |
65 | if (error) { | |
66 | remove_files(dir_sd, kobj, grp); | |
67 | goto exit; | |
68 | } | |
69 | } | |
70 | ||
71 | if (grp->bin_attrs) { | |
72 | for (bin_attr = grp->bin_attrs; *bin_attr; bin_attr++) { | |
73 | if (update) | |
74 | sysfs_remove_bin_file(kobj, *bin_attr); | |
75 | error = sysfs_create_bin_file(kobj, *bin_attr); | |
76 | if (error) | |
77 | break; | |
0f423895 | 78 | } |
6ab9cea1 GKH |
79 | if (error) |
80 | remove_files(dir_sd, kobj, grp); | |
0f423895 | 81 | } |
6ab9cea1 | 82 | exit: |
1da177e4 LT |
83 | return error; |
84 | } | |
85 | ||
86 | ||
0f423895 JB |
87 | static int internal_create_group(struct kobject *kobj, int update, |
88 | const struct attribute_group *grp) | |
1da177e4 | 89 | { |
608e266a | 90 | struct sysfs_dirent *sd; |
1da177e4 LT |
91 | int error; |
92 | ||
0f423895 JB |
93 | BUG_ON(!kobj || (!update && !kobj->sd)); |
94 | ||
95 | /* Updates may happen before the object has been instantiated */ | |
96 | if (unlikely(update && !kobj->sd)) | |
97 | return -EINVAL; | |
388a8c35 OS |
98 | if (!grp->attrs && !grp->bin_attrs) { |
99 | WARN(1, "sysfs: (bin_)attrs not set by subsystem for group: %s/%s\n", | |
5631f2c1 BP |
100 | kobj->name, grp->name ? "" : grp->name); |
101 | return -EINVAL; | |
102 | } | |
1da177e4 | 103 | if (grp->name) { |
608e266a | 104 | error = sysfs_create_subdir(kobj, grp->name, &sd); |
1da177e4 LT |
105 | if (error) |
106 | return error; | |
107 | } else | |
608e266a TH |
108 | sd = kobj->sd; |
109 | sysfs_get(sd); | |
0f423895 | 110 | error = create_files(sd, kobj, grp, update); |
608e266a | 111 | if (error) { |
1da177e4 | 112 | if (grp->name) |
608e266a | 113 | sysfs_remove_subdir(sd); |
1da177e4 | 114 | } |
608e266a | 115 | sysfs_put(sd); |
1da177e4 LT |
116 | return error; |
117 | } | |
118 | ||
0f423895 JB |
119 | /** |
120 | * sysfs_create_group - given a directory kobject, create an attribute group | |
121 | * @kobj: The kobject to create the group on | |
122 | * @grp: The attribute group to create | |
123 | * | |
124 | * This function creates a group for the first time. It will explicitly | |
125 | * warn and error if any of the attribute files being created already exist. | |
126 | * | |
127 | * Returns 0 on success or error. | |
128 | */ | |
129 | int sysfs_create_group(struct kobject *kobj, | |
130 | const struct attribute_group *grp) | |
131 | { | |
132 | return internal_create_group(kobj, 0, grp); | |
133 | } | |
d363bc53 | 134 | EXPORT_SYMBOL_GPL(sysfs_create_group); |
0f423895 | 135 | |
3e9b2bae GKH |
136 | /** |
137 | * sysfs_create_groups - given a directory kobject, create a bunch of attribute groups | |
138 | * @kobj: The kobject to create the group on | |
139 | * @groups: The attribute groups to create, NULL terminated | |
140 | * | |
141 | * This function creates a bunch of attribute groups. If an error occurs when | |
142 | * creating a group, all previously created groups will be removed, unwinding | |
143 | * everything back to the original state when this function was called. | |
144 | * It will explicitly warn and error if any of the attribute files being | |
145 | * created already exist. | |
146 | * | |
09239ed4 | 147 | * Returns 0 on success or error code from sysfs_create_group on error. |
3e9b2bae GKH |
148 | */ |
149 | int sysfs_create_groups(struct kobject *kobj, | |
150 | const struct attribute_group **groups) | |
151 | { | |
152 | int error = 0; | |
153 | int i; | |
154 | ||
155 | if (!groups) | |
156 | return 0; | |
157 | ||
158 | for (i = 0; groups[i]; i++) { | |
159 | error = sysfs_create_group(kobj, groups[i]); | |
160 | if (error) { | |
161 | while (--i >= 0) | |
162 | sysfs_remove_group(kobj, groups[i]); | |
163 | break; | |
164 | } | |
165 | } | |
166 | return error; | |
167 | } | |
168 | EXPORT_SYMBOL_GPL(sysfs_create_groups); | |
169 | ||
0f423895 | 170 | /** |
1f8e1cda RD |
171 | * sysfs_update_group - given a directory kobject, update an attribute group |
172 | * @kobj: The kobject to update the group on | |
173 | * @grp: The attribute group to update | |
0f423895 JB |
174 | * |
175 | * This function updates an attribute group. Unlike | |
176 | * sysfs_create_group(), it will explicitly not warn or error if any | |
177 | * of the attribute files being created already exist. Furthermore, | |
178 | * if the visibility of the files has changed through the is_visible() | |
179 | * callback, it will update the permissions and add or remove the | |
180 | * relevant files. | |
181 | * | |
182 | * The primary use for this function is to call it after making a change | |
183 | * that affects group visibility. | |
184 | * | |
185 | * Returns 0 on success or error. | |
186 | */ | |
187 | int sysfs_update_group(struct kobject *kobj, | |
188 | const struct attribute_group *grp) | |
189 | { | |
190 | return internal_create_group(kobj, 1, grp); | |
191 | } | |
d363bc53 | 192 | EXPORT_SYMBOL_GPL(sysfs_update_group); |
0f423895 | 193 | |
f9ae443b GKH |
194 | /** |
195 | * sysfs_remove_group: remove a group from a kobject | |
196 | * @kobj: kobject to remove the group from | |
197 | * @grp: group to remove | |
198 | * | |
199 | * This function removes a group of attributes from a kobject. The attributes | |
200 | * previously have to have been created for this group, otherwise it will fail. | |
201 | */ | |
995d8ed9 GKH |
202 | void sysfs_remove_group(struct kobject *kobj, |
203 | const struct attribute_group *grp) | |
1da177e4 | 204 | { |
608e266a TH |
205 | struct sysfs_dirent *dir_sd = kobj->sd; |
206 | struct sysfs_dirent *sd; | |
1da177e4 | 207 | |
057f6c01 | 208 | if (grp->name) { |
3ff195b0 | 209 | sd = sysfs_get_dirent(dir_sd, NULL, grp->name); |
969affd2 | 210 | if (!sd) { |
16aebf1c GKH |
211 | WARN(!sd, KERN_WARNING |
212 | "sysfs group %p not found for kobject '%s'\n", | |
213 | grp, kobject_name(kobj)); | |
969affd2 GKH |
214 | return; |
215 | } | |
608e266a TH |
216 | } else |
217 | sd = sysfs_get(dir_sd); | |
1da177e4 | 218 | |
d4acd722 | 219 | remove_files(sd, kobj, grp); |
1da177e4 | 220 | if (grp->name) |
608e266a TH |
221 | sysfs_remove_subdir(sd); |
222 | ||
223 | sysfs_put(sd); | |
1da177e4 | 224 | } |
d363bc53 | 225 | EXPORT_SYMBOL_GPL(sysfs_remove_group); |
1da177e4 | 226 | |
3e9b2bae GKH |
227 | /** |
228 | * sysfs_remove_groups - remove a list of groups | |
229 | * | |
f9ae443b GKH |
230 | * @kobj: The kobject for the groups to be removed from |
231 | * @groups: NULL terminated list of groups to be removed | |
3e9b2bae | 232 | * |
09239ed4 | 233 | * If groups is not NULL, remove the specified groups from the kobject. |
3e9b2bae GKH |
234 | */ |
235 | void sysfs_remove_groups(struct kobject *kobj, | |
236 | const struct attribute_group **groups) | |
237 | { | |
238 | int i; | |
239 | ||
240 | if (!groups) | |
241 | return; | |
242 | for (i = 0; groups[i]; i++) | |
243 | sysfs_remove_group(kobj, groups[i]); | |
244 | } | |
245 | EXPORT_SYMBOL_GPL(sysfs_remove_groups); | |
246 | ||
69d44ffb AS |
247 | /** |
248 | * sysfs_merge_group - merge files into a pre-existing attribute group. | |
249 | * @kobj: The kobject containing the group. | |
250 | * @grp: The files to create and the attribute group they belong to. | |
251 | * | |
252 | * This function returns an error if the group doesn't exist or any of the | |
253 | * files already exist in that group, in which case none of the new files | |
254 | * are created. | |
255 | */ | |
256 | int sysfs_merge_group(struct kobject *kobj, | |
257 | const struct attribute_group *grp) | |
258 | { | |
259 | struct sysfs_dirent *dir_sd; | |
260 | int error = 0; | |
261 | struct attribute *const *attr; | |
262 | int i; | |
263 | ||
e030d58e | 264 | dir_sd = sysfs_get_dirent(kobj->sd, NULL, grp->name); |
69d44ffb AS |
265 | if (!dir_sd) |
266 | return -ENOENT; | |
267 | ||
268 | for ((i = 0, attr = grp->attrs); *attr && !error; (++i, ++attr)) | |
269 | error = sysfs_add_file(dir_sd, *attr, SYSFS_KOBJ_ATTR); | |
270 | if (error) { | |
271 | while (--i >= 0) | |
272 | sysfs_hash_and_remove(dir_sd, NULL, (*--attr)->name); | |
273 | } | |
274 | sysfs_put(dir_sd); | |
275 | ||
276 | return error; | |
277 | } | |
278 | EXPORT_SYMBOL_GPL(sysfs_merge_group); | |
279 | ||
280 | /** | |
281 | * sysfs_unmerge_group - remove files from a pre-existing attribute group. | |
282 | * @kobj: The kobject containing the group. | |
283 | * @grp: The files to remove and the attribute group they belong to. | |
284 | */ | |
285 | void sysfs_unmerge_group(struct kobject *kobj, | |
286 | const struct attribute_group *grp) | |
287 | { | |
288 | struct sysfs_dirent *dir_sd; | |
289 | struct attribute *const *attr; | |
290 | ||
e030d58e | 291 | dir_sd = sysfs_get_dirent(kobj->sd, NULL, grp->name); |
69d44ffb AS |
292 | if (dir_sd) { |
293 | for (attr = grp->attrs; *attr; ++attr) | |
294 | sysfs_hash_and_remove(dir_sd, NULL, (*attr)->name); | |
295 | sysfs_put(dir_sd); | |
296 | } | |
297 | } | |
298 | EXPORT_SYMBOL_GPL(sysfs_unmerge_group); | |
299 | ||
0bb8f3d6 RW |
300 | /** |
301 | * sysfs_add_link_to_group - add a symlink to an attribute group. | |
302 | * @kobj: The kobject containing the group. | |
303 | * @group_name: The name of the group. | |
304 | * @target: The target kobject of the symlink to create. | |
305 | * @link_name: The name of the symlink to create. | |
306 | */ | |
307 | int sysfs_add_link_to_group(struct kobject *kobj, const char *group_name, | |
308 | struct kobject *target, const char *link_name) | |
309 | { | |
310 | struct sysfs_dirent *dir_sd; | |
311 | int error = 0; | |
312 | ||
313 | dir_sd = sysfs_get_dirent(kobj->sd, NULL, group_name); | |
314 | if (!dir_sd) | |
315 | return -ENOENT; | |
316 | ||
317 | error = sysfs_create_link_sd(dir_sd, target, link_name); | |
318 | sysfs_put(dir_sd); | |
319 | ||
320 | return error; | |
321 | } | |
322 | EXPORT_SYMBOL_GPL(sysfs_add_link_to_group); | |
323 | ||
324 | /** | |
325 | * sysfs_remove_link_from_group - remove a symlink from an attribute group. | |
326 | * @kobj: The kobject containing the group. | |
327 | * @group_name: The name of the group. | |
328 | * @link_name: The name of the symlink to remove. | |
329 | */ | |
330 | void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name, | |
331 | const char *link_name) | |
332 | { | |
333 | struct sysfs_dirent *dir_sd; | |
334 | ||
335 | dir_sd = sysfs_get_dirent(kobj->sd, NULL, group_name); | |
336 | if (dir_sd) { | |
337 | sysfs_hash_and_remove(dir_sd, NULL, link_name); | |
338 | sysfs_put(dir_sd); | |
339 | } | |
340 | } | |
341 | EXPORT_SYMBOL_GPL(sysfs_remove_link_from_group); |