]>
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 | |
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> | |
5f45f1a7 | 14 | #include <linux/namei.h> |
1da177e4 LT |
15 | #include <linux/err.h> |
16 | #include "sysfs.h" | |
17 | ||
18 | ||
d4acd722 | 19 | static void remove_files(struct sysfs_dirent *dir_sd, struct kobject *kobj, |
608e266a | 20 | const struct attribute_group *grp) |
1da177e4 LT |
21 | { |
22 | struct attribute *const* attr; | |
d4acd722 | 23 | int i; |
1da177e4 | 24 | |
d4acd722 | 25 | for (i = 0, attr = grp->attrs; *attr; i++, attr++) |
3ff195b0 | 26 | sysfs_hash_and_remove(dir_sd, NULL, (*attr)->name); |
1da177e4 LT |
27 | } |
28 | ||
d4acd722 | 29 | static int create_files(struct sysfs_dirent *dir_sd, struct kobject *kobj, |
0f423895 | 30 | const struct attribute_group *grp, int update) |
1da177e4 LT |
31 | { |
32 | struct attribute *const* attr; | |
d4acd722 | 33 | int error = 0, i; |
1da177e4 | 34 | |
0f423895 JB |
35 | for (i = 0, attr = grp->attrs; *attr && !error; i++, attr++) { |
36 | mode_t mode = 0; | |
37 | ||
38 | /* in update mode, we're changing the permissions or | |
39 | * visibility. Do this by first removing then | |
40 | * re-adding (if required) the file */ | |
41 | if (update) | |
3ff195b0 | 42 | sysfs_hash_and_remove(dir_sd, NULL, (*attr)->name); |
0f423895 JB |
43 | if (grp->is_visible) { |
44 | mode = grp->is_visible(kobj, *attr, i); | |
45 | if (!mode) | |
46 | continue; | |
47 | } | |
48 | error = sysfs_add_file_mode(dir_sd, *attr, SYSFS_KOBJ_ATTR, | |
49 | (*attr)->mode | mode); | |
50 | if (unlikely(error)) | |
51 | break; | |
52 | } | |
1da177e4 | 53 | if (error) |
d4acd722 | 54 | remove_files(dir_sd, kobj, grp); |
1da177e4 LT |
55 | return error; |
56 | } | |
57 | ||
58 | ||
0f423895 JB |
59 | static int internal_create_group(struct kobject *kobj, int update, |
60 | const struct attribute_group *grp) | |
1da177e4 | 61 | { |
608e266a | 62 | struct sysfs_dirent *sd; |
1da177e4 LT |
63 | int error; |
64 | ||
0f423895 JB |
65 | BUG_ON(!kobj || (!update && !kobj->sd)); |
66 | ||
67 | /* Updates may happen before the object has been instantiated */ | |
68 | if (unlikely(update && !kobj->sd)) | |
69 | return -EINVAL; | |
1da177e4 LT |
70 | |
71 | if (grp->name) { | |
608e266a | 72 | error = sysfs_create_subdir(kobj, grp->name, &sd); |
1da177e4 LT |
73 | if (error) |
74 | return error; | |
75 | } else | |
608e266a TH |
76 | sd = kobj->sd; |
77 | sysfs_get(sd); | |
0f423895 | 78 | error = create_files(sd, kobj, grp, update); |
608e266a | 79 | if (error) { |
1da177e4 | 80 | if (grp->name) |
608e266a | 81 | sysfs_remove_subdir(sd); |
1da177e4 | 82 | } |
608e266a | 83 | sysfs_put(sd); |
1da177e4 LT |
84 | return error; |
85 | } | |
86 | ||
0f423895 JB |
87 | /** |
88 | * sysfs_create_group - given a directory kobject, create an attribute group | |
89 | * @kobj: The kobject to create the group on | |
90 | * @grp: The attribute group to create | |
91 | * | |
92 | * This function creates a group for the first time. It will explicitly | |
93 | * warn and error if any of the attribute files being created already exist. | |
94 | * | |
95 | * Returns 0 on success or error. | |
96 | */ | |
97 | int sysfs_create_group(struct kobject *kobj, | |
98 | const struct attribute_group *grp) | |
99 | { | |
100 | return internal_create_group(kobj, 0, grp); | |
101 | } | |
102 | ||
103 | /** | |
104 | * sysfs_update_group - given a directory kobject, create an attribute group | |
105 | * @kobj: The kobject to create the group on | |
106 | * @grp: The attribute group to create | |
107 | * | |
108 | * This function updates an attribute group. Unlike | |
109 | * sysfs_create_group(), it will explicitly not warn or error if any | |
110 | * of the attribute files being created already exist. Furthermore, | |
111 | * if the visibility of the files has changed through the is_visible() | |
112 | * callback, it will update the permissions and add or remove the | |
113 | * relevant files. | |
114 | * | |
115 | * The primary use for this function is to call it after making a change | |
116 | * that affects group visibility. | |
117 | * | |
118 | * Returns 0 on success or error. | |
119 | */ | |
120 | int sysfs_update_group(struct kobject *kobj, | |
121 | const struct attribute_group *grp) | |
122 | { | |
123 | return internal_create_group(kobj, 1, grp); | |
124 | } | |
125 | ||
126 | ||
127 | ||
1da177e4 LT |
128 | void sysfs_remove_group(struct kobject * kobj, |
129 | const struct attribute_group * grp) | |
130 | { | |
608e266a TH |
131 | struct sysfs_dirent *dir_sd = kobj->sd; |
132 | struct sysfs_dirent *sd; | |
1da177e4 | 133 | |
057f6c01 | 134 | if (grp->name) { |
3ff195b0 | 135 | sd = sysfs_get_dirent(dir_sd, NULL, grp->name); |
969affd2 | 136 | if (!sd) { |
99fcd77d | 137 | WARN(!sd, KERN_WARNING "sysfs group %p not found for " |
969affd2 | 138 | "kobject '%s'\n", grp, kobject_name(kobj)); |
969affd2 GKH |
139 | return; |
140 | } | |
608e266a TH |
141 | } else |
142 | sd = sysfs_get(dir_sd); | |
1da177e4 | 143 | |
d4acd722 | 144 | remove_files(sd, kobj, grp); |
1da177e4 | 145 | if (grp->name) |
608e266a TH |
146 | sysfs_remove_subdir(sd); |
147 | ||
148 | sysfs_put(sd); | |
1da177e4 LT |
149 | } |
150 | ||
151 | ||
152 | EXPORT_SYMBOL_GPL(sysfs_create_group); | |
0f423895 | 153 | EXPORT_SYMBOL_GPL(sysfs_update_group); |
1da177e4 | 154 | EXPORT_SYMBOL_GPL(sysfs_remove_group); |