fs/sysfs/group.c

   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>
  14 #include <linux/namei.h>
  15 #include <linux/err.h>
  16 #include "sysfs.h"
  17
  18
  19 static void remove_files(struct dentry * dir,
  20                          const struct attribute_group * grp)
  21 {
  22         struct attribute *const* attr;
  23
  24         for (attr = grp->attrs; *attr; attr++)
  25                 sysfs_hash_and_remove(dir,(*attr)->name);
  26 }
  27
  28 static int create_files(struct dentry * dir,
  29                         const struct attribute_group * grp)
  30 {
  31         struct attribute *const* attr;
  32         int error = 0;
  33
  34         for (attr = grp->attrs; *attr && !error; attr++) {
  35                 error = sysfs_add_file(dir, *attr, SYSFS_KOBJ_ATTR);
  36         }
  37         if (error)
  38                 remove_files(dir,grp);
  39         return error;
  40 }
  41
  42
  43 int sysfs_create_group(struct kobject * kobj,
  44                        const struct attribute_group * grp)
  45 {
  46         struct dentry * dir;
  47         int error;
  48
  49         BUG_ON(!kobj || !kobj->dentry);
  50
  51         if (grp->name) {
  52                 error = sysfs_create_subdir(kobj,grp->name,&dir);
  53                 if (error)
  54                         return error;
  55         } else
  56                 dir = kobj->dentry;
  57         dir = dget(dir);
  58         if ((error = create_files(dir,grp))) {
  59                 if (grp->name)
  60                         sysfs_remove_subdir(dir);
  61         }
  62         dput(dir);
  63         return error;
  64 }
  65
  66 void sysfs_remove_group(struct kobject * kobj,
  67                         const struct attribute_group * grp)
  68 {
  69         struct dentry * dir;
  70
  71         if (grp->name)
  72                 dir = lookup_one_len(grp->name, kobj->dentry,
  73                                 strlen(grp->name));
  74         else
  75                 dir = dget(kobj->dentry);
  76
  77         remove_files(dir,grp);
  78         if (grp->name)
  79                 sysfs_remove_subdir(dir);
  80         /* release the ref. taken in this routine */
  81         dput(dir);
  82 }
  83
  84
  85 EXPORT_SYMBOL_GPL(sysfs_create_group);
  86 EXPORT_SYMBOL_GPL(sysfs_remove_group);