1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
|
/*
* xenfs.c - a filesystem for passing info between the a domain and
* the hypervisor.
*
* 2008-10-07 Alex Zeffertt Replaced /proc/xen/xenbus with xenfs filesystem
* and /proc/xen compatibility mount point.
* Turned xenfs into a loadable module.
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/magic.h>
#include <xen/xen.h>
#include "xenfs.h"
#include <asm/xen/hypervisor.h>
MODULE_DESCRIPTION("Xen filesystem");
MODULE_LICENSE("GPL");
static struct inode *xenfs_make_inode(struct super_block *sb, int mode)
{
struct inode *ret = new_inode(sb);
if (ret) {
ret->i_mode = mode;
ret->i_uid = ret->i_gid = 0;
ret->i_blocks = 0;
ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
}
return ret;
}
static struct dentry *xenfs_create_file(struct super_block *sb,
struct dentry *parent,
const char *name,
const struct file_operations *fops,
void *data,
int mode)
{
struct dentry *dentry;
struct inode *inode;
dentry = d_alloc_name(parent, name);
if (!dentry)
return NULL;
inode = xenfs_make_inode(sb, S_IFREG | mode);
if (!inode) {
dput(dentry);
return NULL;
}
inode->i_fop = fops;
inode->i_private = data;
d_add(dentry, inode);
return dentry;
}
static ssize_t capabilities_read(struct file *file, char __user *buf,
size_t size, loff_t *off)
{
char *tmp = "";
if (xen_initial_domain())
tmp = "control_d\n";
return simple_read_from_buffer(buf, size, off, tmp, strlen(tmp));
}
static const struct file_operations capabilities_file_ops = {
.read = capabilities_read,
};
static int xenfs_fill_super(struct super_block *sb, void *data, int silent)
{
static struct tree_descr xenfs_files[] = {
[1] = {},
{ "xenbus", &xenbus_file_ops, S_IRUSR|S_IWUSR },
{ "capabilities", &capabilities_file_ops, S_IRUGO },
{""},
};
int rc;
rc = simple_fill_super(sb, XENFS_SUPER_MAGIC, xenfs_files);
if (rc < 0)
return rc;
if (xen_initial_domain()) {
xenfs_create_file(sb, sb->s_root, "xsd_kva",
&xsd_kva_file_ops, NULL, S_IRUSR|S_IWUSR);
xenfs_create_file(sb, sb->s_root, "xsd_port",
&xsd_port_file_ops, NULL, S_IRUSR|S_IWUSR);
}
return rc;
}
static int xenfs_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, xenfs_fill_super, mnt);
}
static struct file_system_type xenfs_type = {
.owner = THIS_MODULE,
.name = "xenfs",
.get_sb = xenfs_get_sb,
.kill_sb = kill_litter_super,
};
static int __init xenfs_init(void)
{
if (xen_domain())
return register_filesystem(&xenfs_type);
printk(KERN_INFO "XENFS: not registering filesystem on non-xen platform\n");
return 0;
}
static void __exit xenfs_exit(void)
{
if (xen_domain())
unregister_filesystem(&xenfs_type);
}
module_init(xenfs_init);
module_exit(xenfs_exit);
|
