2 * mount.c - operations for initializing and mounting sysfs.
8 #include <linux/mount.h>
9 #include <linux/pagemap.h>
10 #include <linux/init.h>
14 /* Random magic number */
15 #define SYSFS_MAGIC 0x62656572
17 struct vfsmount *sysfs_mount;
18 struct super_block * sysfs_sb = NULL;
19 kmem_cache_t *sysfs_dir_cachep;
21 static struct super_operations sysfs_ops = {
22 .statfs = simple_statfs,
23 .drop_inode = generic_delete_inode,
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),
34 static int sysfs_fill_super(struct super_block *sb, void *data, int silent)
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;
46 inode = sysfs_new_inode(S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO,
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) */
54 pr_debug("sysfs: could not get root inode\n");
58 root = d_alloc_root(inode);
60 pr_debug("%s: could not get root dentry!\n",__FUNCTION__);
64 root->d_fsdata = &sysfs_root;
69 static struct super_block *sysfs_get_sb(struct file_system_type *fs_type,
70 int flags, const char *dev_name, void *data)
72 return get_sb_single(fs_type, flags, data, sysfs_fill_super);
75 static struct file_system_type sysfs_fs_type = {
77 .get_sb = sysfs_get_sb,
78 .kill_sb = kill_litter_super,
81 int __init sysfs_init(void)
85 sysfs_dir_cachep = kmem_cache_create("sysfs_dir_cache",
86 sizeof(struct sysfs_dirent),
88 if (!sysfs_dir_cachep)
91 err = register_filesystem(&sysfs_fs_type);
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);
98 unregister_filesystem(&sysfs_fs_type);
106 kmem_cache_destroy(sysfs_dir_cachep);
107 sysfs_dir_cachep = NULL;