]>
git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blob - fs/sysfs/group.c
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
7 * This file is released undert the GPL v2.
11 #include <linux/kobject.h>
12 #include <linux/module.h>
13 #include <linux/dcache.h>
14 #include <linux/namei.h>
15 #include <linux/err.h>
19 static void remove_files(struct sysfs_dirent
*dir_sd
, struct kobject
*kobj
,
20 const struct attribute_group
*grp
)
22 struct attribute
*const* attr
;
25 for (i
= 0, attr
= grp
->attrs
; *attr
; i
++, attr
++)
26 sysfs_hash_and_remove(dir_sd
, NULL
, (*attr
)->name
);
29 static int create_files(struct sysfs_dirent
*dir_sd
, struct kobject
*kobj
,
30 const struct attribute_group
*grp
, int update
)
32 struct attribute
*const* attr
;
35 for (i
= 0, attr
= grp
->attrs
; *attr
&& !error
; i
++, attr
++) {
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 */
42 sysfs_hash_and_remove(dir_sd
, NULL
, (*attr
)->name
);
43 if (grp
->is_visible
) {
44 mode
= grp
->is_visible(kobj
, *attr
, i
);
48 error
= sysfs_add_file_mode(dir_sd
, *attr
, SYSFS_KOBJ_ATTR
,
49 (*attr
)->mode
| mode
);
54 remove_files(dir_sd
, kobj
, grp
);
59 static int internal_create_group(struct kobject
*kobj
, int update
,
60 const struct attribute_group
*grp
)
62 struct sysfs_dirent
*sd
;
65 BUG_ON(!kobj
|| (!update
&& !kobj
->sd
));
67 /* Updates may happen before the object has been instantiated */
68 if (unlikely(update
&& !kobj
->sd
))
72 error
= sysfs_create_subdir(kobj
, grp
->name
, &sd
);
78 error
= create_files(sd
, kobj
, grp
, update
);
81 sysfs_remove_subdir(sd
);
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
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.
95 * Returns 0 on success or error.
97 int sysfs_create_group(struct kobject
*kobj
,
98 const struct attribute_group
*grp
)
100 return internal_create_group(kobj
, 0, grp
);
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
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
115 * The primary use for this function is to call it after making a change
116 * that affects group visibility.
118 * Returns 0 on success or error.
120 int sysfs_update_group(struct kobject
*kobj
,
121 const struct attribute_group
*grp
)
123 return internal_create_group(kobj
, 1, grp
);
128 void sysfs_remove_group(struct kobject
* kobj
,
129 const struct attribute_group
* grp
)
131 struct sysfs_dirent
*dir_sd
= kobj
->sd
;
132 struct sysfs_dirent
*sd
;
135 sd
= sysfs_get_dirent(dir_sd
, NULL
, grp
->name
);
137 WARN(!sd
, KERN_WARNING
"sysfs group %p not found for "
138 "kobject '%s'\n", grp
, kobject_name(kobj
));
142 sd
= sysfs_get(dir_sd
);
144 remove_files(sd
, kobj
, grp
);
146 sysfs_remove_subdir(sd
);
152 EXPORT_SYMBOL_GPL(sysfs_create_group
);
153 EXPORT_SYMBOL_GPL(sysfs_update_group
);
154 EXPORT_SYMBOL_GPL(sysfs_remove_group
);