[PATCH] slab: remove kmem_cache_t
[linux-3.10.git] / fs / sysfs / mount.c
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;
19 struct kmem_cache *sysfs_dir_cachep;
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,
31         .s_iattr        = NULL,
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
46         inode = sysfs_new_inode(S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO,
47                                  &sysfs_root);
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) */
52                 inc_nlink(inode);
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
69 static int sysfs_get_sb(struct file_system_type *fs_type,
70         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
71 {
72         return get_sb_single(fs_type, flags, data, sysfs_fill_super, mnt);
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 }