release/src-rt-6.x.4708/linux/linux-2.6.36/fs/ocfs2/cluster/sys.c

   1 /* -*- mode: c; c-basic-offset: 8; -*-
   2  * vim: noexpandtab sw=8 ts=8 sts=0:
   3  *
   4  * sys.c
   5  *
   6  * OCFS2 cluster sysfs interface
   7  *
   8  * Copyright (C) 2005 Oracle.  All rights reserved.
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public
  12  * License as published by the Free Software Foundation,
  13  * version 2 of the License.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public
  21  * License along with this program; if not, write to the
  22  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  23  * Boston, MA 021110-1307, USA.
  24  *
  25  */
  26
  27 #include <linux/kernel.h>
  28 #include <linux/module.h>
  29 #include <linux/kobject.h>
  30 #include <linux/sysfs.h>
  31 #include <linux/fs.h>
  32
  33 #include "ocfs2_nodemanager.h"
  34 #include "masklog.h"
  35 #include "sys.h"
  36
  37
  38 static ssize_t version_show(struct kobject *kobj, struct kobj_attribute *attr,
  39                             char *buf)
  40 {
  41         return snprintf(buf, PAGE_SIZE, "%u\n", O2NM_API_VERSION);
  42 }
  43 static struct kobj_attribute attr_version =
  44         __ATTR(interface_revision, S_IFREG | S_IRUGO, version_show, NULL);
  45
  46 static struct attribute *o2cb_attrs[] = {
  47         &attr_version.attr,
  48         NULL,
  49 };
  50
  51 static struct attribute_group o2cb_attr_group = {
  52         .attrs = o2cb_attrs,
  53 };
  54
  55 static struct kset *o2cb_kset;
  56
  57 void o2cb_sys_shutdown(void)
  58 {
  59         mlog_sys_shutdown();
  60         sysfs_remove_link(NULL, "o2cb");
  61         kset_unregister(o2cb_kset);
  62 }
  63
  64 int o2cb_sys_init(void)
  65 {
  66         int ret;
  67
  68         o2cb_kset = kset_create_and_add("o2cb", NULL, fs_kobj);
  69         if (!o2cb_kset)
  70                 return -ENOMEM;
  71
  72         /*
  73          * Create this symlink for backwards compatibility with old
  74          * versions of ocfs2-tools which look for things in /sys/o2cb.
  75          */
  76         ret = sysfs_create_link(NULL, &o2cb_kset->kobj, "o2cb");
  77         if (ret)
  78                 goto error;
  79
  80         ret = sysfs_create_group(&o2cb_kset->kobj, &o2cb_attr_group);
  81         if (ret)
  82                 goto error;
  83
  84         ret = mlog_sys_init(o2cb_kset);
  85         if (ret)
  86                 goto error;
  87         return 0;
  88 error:
  89         kset_unregister(o2cb_kset);
  90         return ret;
  91 }