[linux.git] / fs / sysfs / mount.c

/*
 * mount.c - operations for initializing and mounting sysfs.
 */

#define DEBUG 

#include <linux/fs.h>
#include <linux/mount.h>
#include <linux/pagemap.h>
#include <linux/init.h>

#include "sysfs.h"

/* Random magic number */
#define SYSFS_MAGIC 0x62656572

struct vfsmount *sysfs_mount;
struct super_block * sysfs_sb = NULL;
struct kmem_cache *sysfs_dir_cachep;

static struct super_operations sysfs_ops = {
	.statfs		= simple_statfs,
	.drop_inode	= generic_delete_inode,
};

static struct sysfs_dirent sysfs_root = {
	.s_sibling	= LIST_HEAD_INIT(sysfs_root.s_sibling),
	.s_children	= LIST_HEAD_INIT(sysfs_root.s_children),
	.s_element	= NULL,
	.s_type		= SYSFS_ROOT,
	.s_iattr	= NULL,
};

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;

	inode = sysfs_new_inode(S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO,
				 &sysfs_root);
	if (inode) {
		inode->i_op = &sysfs_dir_inode_operations;
		inode->i_fop = &sysfs_dir_operations;
		/* directory inodes start off with i_nlink == 2 (for "." entry) */
		inc_nlink(inode);
	} else {
		pr_debug("sysfs: could not get root inode\n");
		return -ENOMEM;
	}

	root = d_alloc_root(inode);
	if (!root) {
		pr_debug("%s: could not get root dentry!\n",__FUNCTION__);
		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_litter_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, NULL);
	if (!sysfs_dir_cachep)
		goto out;

	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;
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* mount.c - operations for initializing and mounting sysfs.
	3	*/
	4
	5	#define DEBUG
	6
	7	#include <linux/fs.h>
	8	#include <linux/mount.h>
	9	#include <linux/pagemap.h>
	10	#include <linux/init.h>
	11
	12	#include "sysfs.h"
	13
	14	/* Random magic number */
	15	#define SYSFS_MAGIC 0x62656572
	16
	17	struct vfsmount *sysfs_mount;
	18	struct super_block * sysfs_sb = NULL;
e18b890b	19	struct kmem_cache *sysfs_dir_cachep;
1da177e4 LT	20
	21	static struct super_operations sysfs_ops = {
	22	.statfs = simple_statfs,
	23	.drop_inode = generic_delete_inode,
	24	};
	25
	26	static struct sysfs_dirent sysfs_root = {
	27	.s_sibling = LIST_HEAD_INIT(sysfs_root.s_sibling),
	28	.s_children = LIST_HEAD_INIT(sysfs_root.s_children),
	29	.s_element = NULL,
	30	.s_type = SYSFS_ROOT,
8215534c	31	.s_iattr = NULL,
1da177e4 LT	32	};
	33
	34	static int sysfs_fill_super(struct super_block sb, void data, int silent)
	35	{
	36	struct inode *inode;
	37	struct dentry *root;
	38
	39	sb->s_blocksize = PAGE_CACHE_SIZE;
	40	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
	41	sb->s_magic = SYSFS_MAGIC;
	42	sb->s_op = &sysfs_ops;
	43	sb->s_time_gran = 1;
	44	sysfs_sb = sb;
	45
8215534c MS	46	inode = sysfs_new_inode(S_IFDIR \| S_IRWXU \| S_IRUGO \| S_IXUGO,
8215534c MS	47	&sysfs_root);
1da177e4 LT	48	if (inode) {
	49	inode->i_op = &sysfs_dir_inode_operations;
	50	inode->i_fop = &sysfs_dir_operations;
	51	/* directory inodes start off with i_nlink == 2 (for "." entry) */
d8c76e6f	52	inc_nlink(inode);
1da177e4 LT	53	} else {
	54	pr_debug("sysfs: could not get root inode\n");
	55	return -ENOMEM;
	56	}
	57
	58	root = d_alloc_root(inode);
	59	if (!root) {
	60	pr_debug("%s: could not get root dentry!\n",__FUNCTION__);
	61	iput(inode);
	62	return -ENOMEM;
	63	}
	64	root->d_fsdata = &sysfs_root;
	65	sb->s_root = root;
	66	return 0;
	67	}
	68
454e2398 DH	69	static int sysfs_get_sb(struct file_system_type *fs_type,
454e2398 DH	70	int flags, const char dev_name, void data, struct vfsmount *mnt)
1da177e4	71	{
454e2398	72	return get_sb_single(fs_type, flags, data, sysfs_fill_super, mnt);
1da177e4 LT	73	}
	74
	75	static struct file_system_type sysfs_fs_type = {
	76	.name = "sysfs",
	77	.get_sb = sysfs_get_sb,
	78	.kill_sb = kill_litter_super,
	79	};
	80
	81	int __init sysfs_init(void)
	82	{
	83	int err = -ENOMEM;
	84
	85	sysfs_dir_cachep = kmem_cache_create("sysfs_dir_cache",
	86	sizeof(struct sysfs_dirent),
	87	0, 0, NULL, NULL);
	88	if (!sysfs_dir_cachep)
	89	goto out;
	90
	91	err = register_filesystem(&sysfs_fs_type);
	92	if (!err) {
	93	sysfs_mount = kern_mount(&sysfs_fs_type);
	94	if (IS_ERR(sysfs_mount)) {
	95	printk(KERN_ERR "sysfs: could not mount!\n");
	96	err = PTR_ERR(sysfs_mount);
	97	sysfs_mount = NULL;
	98	unregister_filesystem(&sysfs_fs_type);
	99	goto out_err;
	100	}
	101	} else
	102	goto out_err;
	103	out:
	104	return err;
	105	out_err:
	106	kmem_cache_destroy(sysfs_dir_cachep);
	107	sysfs_dir_cachep = NULL;
	108	goto out;
	109	}