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 | ||
9f70a401 | 21 | static void remove_files(struct kernfs_node *parent, |
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++) | |
324a56e1 | 29 | kernfs_remove_by_name(parent, (*attr)->name); |
6ab9cea1 GKH |
30 | if (grp->bin_attrs) |
31 | for (bin_attr = grp->bin_attrs; *bin_attr; bin_attr++) | |
9f70a401 | 32 | kernfs_remove_by_name(parent, (*bin_attr)->attr.name); |
1da177e4 LT |
33 | } |
34 | ||
324a56e1 | 35 | static int create_files(struct kernfs_node *parent, 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) | |
324a56e1 | 52 | kernfs_remove_by_name(parent, (*attr)->name); |
6ab9cea1 GKH |
53 | if (grp->is_visible) { |
54 | mode = grp->is_visible(kobj, *attr, i); | |
55 | if (!mode) | |
56 | continue; | |
57 | } | |
324a56e1 | 58 | error = sysfs_add_file_mode_ns(parent, *attr, false, |
58292cbe TH |
59 | (*attr)->mode | mode, |
60 | NULL); | |
6ab9cea1 GKH |
61 | if (unlikely(error)) |
62 | break; | |
63 | } | |
64 | if (error) { | |
9f70a401 | 65 | remove_files(parent, grp); |
6ab9cea1 GKH |
66 | goto exit; |
67 | } | |
68 | } | |
69 | ||
70 | if (grp->bin_attrs) { | |
71 | for (bin_attr = grp->bin_attrs; *bin_attr; bin_attr++) { | |
72 | if (update) | |
aabaf4c2 CS |
73 | kernfs_remove_by_name(parent, |
74 | (*bin_attr)->attr.name); | |
75 | error = sysfs_add_file_mode_ns(parent, | |
76 | &(*bin_attr)->attr, true, | |
77 | (*bin_attr)->attr.mode, NULL); | |
6ab9cea1 GKH |
78 | if (error) |
79 | break; | |
0f423895 | 80 | } |
6ab9cea1 | 81 | if (error) |
9f70a401 | 82 | remove_files(parent, grp); |
0f423895 | 83 | } |
6ab9cea1 | 84 | exit: |
1da177e4 LT |
85 | return error; |
86 | } | |
87 | ||
88 | ||
0f423895 JB |
89 | static int internal_create_group(struct kobject *kobj, int update, |
90 | const struct attribute_group *grp) | |
1da177e4 | 91 | { |
324a56e1 | 92 | struct kernfs_node *kn; |
1da177e4 LT |
93 | int error; |
94 | ||
0f423895 JB |
95 | BUG_ON(!kobj || (!update && !kobj->sd)); |
96 | ||
97 | /* Updates may happen before the object has been instantiated */ | |
98 | if (unlikely(update && !kobj->sd)) | |
99 | return -EINVAL; | |
388a8c35 OS |
100 | if (!grp->attrs && !grp->bin_attrs) { |
101 | WARN(1, "sysfs: (bin_)attrs not set by subsystem for group: %s/%s\n", | |
adf305f7 | 102 | kobj->name, grp->name ?: ""); |
5631f2c1 BP |
103 | return -EINVAL; |
104 | } | |
1da177e4 | 105 | if (grp->name) { |
bb8b9d09 TH |
106 | kn = kernfs_create_dir(kobj->sd, grp->name, |
107 | S_IRWXU | S_IRUGO | S_IXUGO, kobj); | |
324a56e1 TH |
108 | if (IS_ERR(kn)) { |
109 | if (PTR_ERR(kn) == -EEXIST) | |
93b2b8e4 | 110 | sysfs_warn_dup(kobj->sd, grp->name); |
324a56e1 | 111 | return PTR_ERR(kn); |
93b2b8e4 | 112 | } |
1da177e4 | 113 | } else |
324a56e1 TH |
114 | kn = kobj->sd; |
115 | kernfs_get(kn); | |
116 | error = create_files(kn, kobj, grp, update); | |
608e266a | 117 | if (error) { |
1da177e4 | 118 | if (grp->name) |
324a56e1 | 119 | kernfs_remove(kn); |
1da177e4 | 120 | } |
324a56e1 | 121 | kernfs_put(kn); |
1da177e4 LT |
122 | return error; |
123 | } | |
124 | ||
0f423895 JB |
125 | /** |
126 | * sysfs_create_group - given a directory kobject, create an attribute group | |
127 | * @kobj: The kobject to create the group on | |
128 | * @grp: The attribute group to create | |
129 | * | |
130 | * This function creates a group for the first time. It will explicitly | |
131 | * warn and error if any of the attribute files being created already exist. | |
132 | * | |
133 | * Returns 0 on success or error. | |
134 | */ | |
135 | int sysfs_create_group(struct kobject *kobj, | |
136 | const struct attribute_group *grp) | |
137 | { | |
138 | return internal_create_group(kobj, 0, grp); | |
139 | } | |
d363bc53 | 140 | EXPORT_SYMBOL_GPL(sysfs_create_group); |
0f423895 | 141 | |
3e9b2bae GKH |
142 | /** |
143 | * sysfs_create_groups - given a directory kobject, create a bunch of attribute groups | |
144 | * @kobj: The kobject to create the group on | |
145 | * @groups: The attribute groups to create, NULL terminated | |
146 | * | |
147 | * This function creates a bunch of attribute groups. If an error occurs when | |
148 | * creating a group, all previously created groups will be removed, unwinding | |
149 | * everything back to the original state when this function was called. | |
150 | * It will explicitly warn and error if any of the attribute files being | |
151 | * created already exist. | |
152 | * | |
09239ed4 | 153 | * Returns 0 on success or error code from sysfs_create_group on error. |
3e9b2bae GKH |
154 | */ |
155 | int sysfs_create_groups(struct kobject *kobj, | |
156 | const struct attribute_group **groups) | |
157 | { | |
158 | int error = 0; | |
159 | int i; | |
160 | ||
161 | if (!groups) | |
162 | return 0; | |
163 | ||
164 | for (i = 0; groups[i]; i++) { | |
165 | error = sysfs_create_group(kobj, groups[i]); | |
166 | if (error) { | |
167 | while (--i >= 0) | |
168 | sysfs_remove_group(kobj, groups[i]); | |
169 | break; | |
170 | } | |
171 | } | |
172 | return error; | |
173 | } | |
174 | EXPORT_SYMBOL_GPL(sysfs_create_groups); | |
175 | ||
0f423895 | 176 | /** |
1f8e1cda RD |
177 | * sysfs_update_group - given a directory kobject, update an attribute group |
178 | * @kobj: The kobject to update the group on | |
179 | * @grp: The attribute group to update | |
0f423895 JB |
180 | * |
181 | * This function updates an attribute group. Unlike | |
182 | * sysfs_create_group(), it will explicitly not warn or error if any | |
183 | * of the attribute files being created already exist. Furthermore, | |
184 | * if the visibility of the files has changed through the is_visible() | |
185 | * callback, it will update the permissions and add or remove the | |
186 | * relevant files. | |
187 | * | |
188 | * The primary use for this function is to call it after making a change | |
189 | * that affects group visibility. | |
190 | * | |
191 | * Returns 0 on success or error. | |
192 | */ | |
193 | int sysfs_update_group(struct kobject *kobj, | |
194 | const struct attribute_group *grp) | |
195 | { | |
196 | return internal_create_group(kobj, 1, grp); | |
197 | } | |
d363bc53 | 198 | EXPORT_SYMBOL_GPL(sysfs_update_group); |
0f423895 | 199 | |
f9ae443b GKH |
200 | /** |
201 | * sysfs_remove_group: remove a group from a kobject | |
202 | * @kobj: kobject to remove the group from | |
203 | * @grp: group to remove | |
204 | * | |
205 | * This function removes a group of attributes from a kobject. The attributes | |
206 | * previously have to have been created for this group, otherwise it will fail. | |
207 | */ | |
995d8ed9 GKH |
208 | void sysfs_remove_group(struct kobject *kobj, |
209 | const struct attribute_group *grp) | |
1da177e4 | 210 | { |
324a56e1 TH |
211 | struct kernfs_node *parent = kobj->sd; |
212 | struct kernfs_node *kn; | |
1da177e4 | 213 | |
057f6c01 | 214 | if (grp->name) { |
324a56e1 TH |
215 | kn = kernfs_find_and_get(parent, grp->name); |
216 | if (!kn) { | |
217 | WARN(!kn, KERN_WARNING | |
16aebf1c GKH |
218 | "sysfs group %p not found for kobject '%s'\n", |
219 | grp, kobject_name(kobj)); | |
969affd2 GKH |
220 | return; |
221 | } | |
ccf73cf3 | 222 | } else { |
324a56e1 TH |
223 | kn = parent; |
224 | kernfs_get(kn); | |
ccf73cf3 | 225 | } |
1da177e4 | 226 | |
9f70a401 | 227 | remove_files(kn, grp); |
1da177e4 | 228 | if (grp->name) |
324a56e1 | 229 | kernfs_remove(kn); |
608e266a | 230 | |
324a56e1 | 231 | kernfs_put(kn); |
1da177e4 | 232 | } |
d363bc53 | 233 | EXPORT_SYMBOL_GPL(sysfs_remove_group); |
1da177e4 | 234 | |
3e9b2bae GKH |
235 | /** |
236 | * sysfs_remove_groups - remove a list of groups | |
237 | * | |
f9ae443b GKH |
238 | * @kobj: The kobject for the groups to be removed from |
239 | * @groups: NULL terminated list of groups to be removed | |
3e9b2bae | 240 | * |
09239ed4 | 241 | * If groups is not NULL, remove the specified groups from the kobject. |
3e9b2bae GKH |
242 | */ |
243 | void sysfs_remove_groups(struct kobject *kobj, | |
244 | const struct attribute_group **groups) | |
245 | { | |
246 | int i; | |
247 | ||
248 | if (!groups) | |
249 | return; | |
250 | for (i = 0; groups[i]; i++) | |
251 | sysfs_remove_group(kobj, groups[i]); | |
252 | } | |
253 | EXPORT_SYMBOL_GPL(sysfs_remove_groups); | |
254 | ||
69d44ffb AS |
255 | /** |
256 | * sysfs_merge_group - merge files into a pre-existing attribute group. | |
257 | * @kobj: The kobject containing the group. | |
258 | * @grp: The files to create and the attribute group they belong to. | |
259 | * | |
260 | * This function returns an error if the group doesn't exist or any of the | |
261 | * files already exist in that group, in which case none of the new files | |
262 | * are created. | |
263 | */ | |
264 | int sysfs_merge_group(struct kobject *kobj, | |
265 | const struct attribute_group *grp) | |
266 | { | |
324a56e1 | 267 | struct kernfs_node *parent; |
69d44ffb AS |
268 | int error = 0; |
269 | struct attribute *const *attr; | |
270 | int i; | |
271 | ||
324a56e1 TH |
272 | parent = kernfs_find_and_get(kobj->sd, grp->name); |
273 | if (!parent) | |
69d44ffb AS |
274 | return -ENOENT; |
275 | ||
276 | for ((i = 0, attr = grp->attrs); *attr && !error; (++i, ++attr)) | |
324a56e1 | 277 | error = sysfs_add_file(parent, *attr, false); |
69d44ffb AS |
278 | if (error) { |
279 | while (--i >= 0) | |
324a56e1 | 280 | kernfs_remove_by_name(parent, (*--attr)->name); |
69d44ffb | 281 | } |
324a56e1 | 282 | kernfs_put(parent); |
69d44ffb AS |
283 | |
284 | return error; | |
285 | } | |
286 | EXPORT_SYMBOL_GPL(sysfs_merge_group); | |
287 | ||
288 | /** | |
289 | * sysfs_unmerge_group - remove files from a pre-existing attribute group. | |
290 | * @kobj: The kobject containing the group. | |
291 | * @grp: The files to remove and the attribute group they belong to. | |
292 | */ | |
293 | void sysfs_unmerge_group(struct kobject *kobj, | |
294 | const struct attribute_group *grp) | |
295 | { | |
324a56e1 | 296 | struct kernfs_node *parent; |
69d44ffb AS |
297 | struct attribute *const *attr; |
298 | ||
324a56e1 TH |
299 | parent = kernfs_find_and_get(kobj->sd, grp->name); |
300 | if (parent) { | |
69d44ffb | 301 | for (attr = grp->attrs; *attr; ++attr) |
324a56e1 TH |
302 | kernfs_remove_by_name(parent, (*attr)->name); |
303 | kernfs_put(parent); | |
69d44ffb AS |
304 | } |
305 | } | |
306 | EXPORT_SYMBOL_GPL(sysfs_unmerge_group); | |
307 | ||
0bb8f3d6 RW |
308 | /** |
309 | * sysfs_add_link_to_group - add a symlink to an attribute group. | |
310 | * @kobj: The kobject containing the group. | |
311 | * @group_name: The name of the group. | |
312 | * @target: The target kobject of the symlink to create. | |
313 | * @link_name: The name of the symlink to create. | |
314 | */ | |
315 | int sysfs_add_link_to_group(struct kobject *kobj, const char *group_name, | |
316 | struct kobject *target, const char *link_name) | |
317 | { | |
324a56e1 | 318 | struct kernfs_node *parent; |
0bb8f3d6 RW |
319 | int error = 0; |
320 | ||
324a56e1 TH |
321 | parent = kernfs_find_and_get(kobj->sd, group_name); |
322 | if (!parent) | |
0bb8f3d6 RW |
323 | return -ENOENT; |
324 | ||
324a56e1 TH |
325 | error = sysfs_create_link_sd(parent, target, link_name); |
326 | kernfs_put(parent); | |
0bb8f3d6 RW |
327 | |
328 | return error; | |
329 | } | |
330 | EXPORT_SYMBOL_GPL(sysfs_add_link_to_group); | |
331 | ||
332 | /** | |
333 | * sysfs_remove_link_from_group - remove a symlink from an attribute group. | |
334 | * @kobj: The kobject containing the group. | |
335 | * @group_name: The name of the group. | |
336 | * @link_name: The name of the symlink to remove. | |
337 | */ | |
338 | void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name, | |
339 | const char *link_name) | |
340 | { | |
324a56e1 | 341 | struct kernfs_node *parent; |
0bb8f3d6 | 342 | |
324a56e1 TH |
343 | parent = kernfs_find_and_get(kobj->sd, group_name); |
344 | if (parent) { | |
345 | kernfs_remove_by_name(parent, link_name); | |
346 | kernfs_put(parent); | |
0bb8f3d6 RW |
347 | } |
348 | } | |
349 | EXPORT_SYMBOL_GPL(sysfs_remove_link_from_group); |