135 lines
2.9 KiB
C
135 lines
2.9 KiB
C
|
/*
|
||
|
|
* fs/sysfs/symlink.c - operations for initializing and mounting sysfs
|
||
|
|
*
|
||
|
|
* Copyright (c) 2001-3 Patrick Mochel
|
||
|
|
* Copyright (c) 2007 SUSE Linux Products GmbH
|
||
|
|
* Copyright (c) 2007 Tejun Heo <teheo@suse.de>
|
||
|
|
*
|
||
|
|
* This file is released under the GPLv2.
|
||
|
|
*
|
||
|
|
* Please see Documentation/filesystems/sysfs.txt for more information.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#define DEBUG
|
||
|
|
|
||
|
|
#include <linux/fs.h>
|
||
|
|
#include <linux/mount.h>
|
||
|
|
#include <linux/pagemap.h>
|
||
|
|
#include <linux/init.h>
|
||
|
|
#include <linux/module.h>
|
||
|
|
#include <linux/magic.h>
|
||
|
|
|
||
|
|
#include "sysfs.h"
|
||
|
|
|
||
|
|
|
||
|
|
static struct vfsmount *sysfs_mount;
|
||
|
|
struct super_block * sysfs_sb = NULL;
|
||
|
|
struct kmem_cache *sysfs_dir_cachep;
|
||
|
|
|
||
|
|
static const struct super_operations sysfs_ops = {
|
||
|
|
.statfs = simple_statfs,
|
||
|
|
.drop_inode = generic_delete_inode,
|
||
|
|
.delete_inode = sysfs_delete_inode,
|
||
|
|
};
|
||
|
|
|
||
|
|
struct sysfs_dirent sysfs_root = {
|
||
|
|
.s_name = "",
|
||
|
|
.s_count = ATOMIC_INIT(1),
|
||
|
|
.s_flags = SYSFS_DIR,
|
||
|
|
.s_mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO,
|
||
|
|
.s_ino = 1,
|
||
|
|
};
|
||
|
|
|
||
|
|
static int sysfs_fill_super(struct super_block *sb, void *data, int silent)
|
||
|
|
{
|
||
|
|
struct inode *inode;
|
||
|
|
struct dentry *root;
|
||
|
|
|
||
|
|
sb->s_blocksize = PAGE_CACHE_SIZE;
|
||
|
|
sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
|
||
|
|
sb->s_magic = SYSFS_MAGIC;
|
||
|
|
sb->s_op = &sysfs_ops;
|
||
|
|
sb->s_time_gran = 1;
|
||
|
|
sysfs_sb = sb;
|
||
|
|
|
||
|
|
/* get root inode, initialize and unlock it */
|
||
|
|
mutex_lock(&sysfs_mutex);
|
||
|
|
inode = sysfs_get_inode(&sysfs_root);
|
||
|
|
mutex_unlock(&sysfs_mutex);
|
||
|
|
if (!inode) {
|
||
|
|
pr_debug("sysfs: could not get root inode\n");
|
||
|
|
return -ENOMEM;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* instantiate and link root dentry */
|
||
|
|
root = d_alloc_root(inode);
|
||
|
|
if (!root) {
|
||
|
|
pr_debug("%s: could not get root dentry!\n",__func__);
|
||
|
|
iput(inode);
|
||
|
|
return -ENOMEM;
|
||
|
|
}
|
||
|
|
root->d_fsdata = &sysfs_root;
|
||
|
|
sb->s_root = root;
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int sysfs_get_sb(struct file_system_type *fs_type,
|
||
|
|
int flags, const char *dev_name, void *data, struct vfsmount *mnt)
|
||
|
|
{
|
||
|
|
return get_sb_single(fs_type, flags, data, sysfs_fill_super, mnt);
|
||
|
|
}
|
||
|
|
|
||
|
|
static struct file_system_type sysfs_fs_type = {
|
||
|
|
.name = "sysfs",
|
||
|
|
.get_sb = sysfs_get_sb,
|
||
|
|
.kill_sb = kill_anon_super,
|
||
|
|
};
|
||
|
|
|
||
|
|
int __init sysfs_init(void)
|
||
|
|
{
|
||
|
|
int err = -ENOMEM;
|
||
|
|
|
||
|
|
sysfs_dir_cachep = kmem_cache_create("sysfs_dir_cache",
|
||
|
|
sizeof(struct sysfs_dirent),
|
||
|
|
0, 0, NULL);
|
||
|
|
if (!sysfs_dir_cachep)
|
||
|
|
goto out;
|
||
|
|
|
||
|
|
err = sysfs_inode_init();
|
||
|
|
if (err)
|
||
|
|
goto out_err;
|
||
|
|
|
||
|
|
err = register_filesystem(&sysfs_fs_type);
|
||
|
|
if (!err) {
|
||
|
|
sysfs_mount = kern_mount(&sysfs_fs_type);
|
||
|
|
if (IS_ERR(sysfs_mount)) {
|
||
|
|
printk(KERN_ERR "sysfs: could not mount!\n");
|
||
|
|
err = PTR_ERR(sysfs_mount);
|
||
|
|
sysfs_mount = NULL;
|
||
|
|
unregister_filesystem(&sysfs_fs_type);
|
||
|
|
goto out_err;
|
||
|
|
}
|
||
|
|
} else
|
||
|
|
goto out_err;
|
||
|
|
out:
|
||
|
|
return err;
|
||
|
|
out_err:
|
||
|
|
kmem_cache_destroy(sysfs_dir_cachep);
|
||
|
|
sysfs_dir_cachep = NULL;
|
||
|
|
goto out;
|
||
|
|
}
|
||
|
|
|
||
|
|
#undef sysfs_get
|
||
|
|
struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd)
|
||
|
|
{
|
||
|
|
return __sysfs_get(sd);
|
||
|
|
}
|
||
|
|
EXPORT_SYMBOL_GPL(sysfs_get);
|
||
|
|
|
||
|
|
#undef sysfs_put
|
||
|
|
void sysfs_put(struct sysfs_dirent *sd)
|
||
|
|
{
|
||
|
|
__sysfs_put(sd);
|
||
|
|
}
|
||
|
|
EXPORT_SYMBOL_GPL(sysfs_put);
|