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
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
|
/* $Id: capifs.c,v 1.1.2.3 2004/01/16 21:09:26 keil Exp $
*
* Copyright 2000 by Carsten Paeth <calle@calle.de>
*
* Heavily based on devpts filesystem from H. Peter Anvin
*
* This software may be used and distributed according to the terms
* of the GNU General Public License, incorporated herein by reference.
*
*/
#include <linux/fs.h>
#include <linux/mount.h>
#include <linux/namei.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/ctype.h>
#include <linux/sched.h> /* current */
#include "capifs.h"
MODULE_DESCRIPTION("CAPI4Linux: /dev/capi/ filesystem");
MODULE_AUTHOR("Carsten Paeth");
MODULE_LICENSE("GPL");
/* ------------------------------------------------------------------ */
static char *revision = "$Revision: 1.1.2.3 $";
/* ------------------------------------------------------------------ */
#define CAPIFS_SUPER_MAGIC (('C'<<8)|'N')
static struct vfsmount *capifs_mnt;
static struct dentry *capifs_root;
static struct {
int setuid;
int setgid;
uid_t uid;
gid_t gid;
umode_t mode;
} config = {.mode = 0600};
/* ------------------------------------------------------------------ */
static int capifs_remount(struct super_block *s, int *flags, char *data)
{
int setuid = 0;
int setgid = 0;
uid_t uid = 0;
gid_t gid = 0;
umode_t mode = 0600;
char *this_char;
char *new_opt = kstrdup(data, GFP_KERNEL);
this_char = NULL;
while ((this_char = strsep(&data, ",")) != NULL) {
int n;
char dummy;
if (!*this_char)
continue;
if (sscanf(this_char, "uid=%i%c", &n, &dummy) == 1) {
setuid = 1;
uid = n;
} else if (sscanf(this_char, "gid=%i%c", &n, &dummy) == 1) {
setgid = 1;
gid = n;
} else if (sscanf(this_char, "mode=%o%c", &n, &dummy) == 1)
mode = n & ~S_IFMT;
else {
kfree(new_opt);
printk("capifs: called with bogus options\n");
return -EINVAL;
}
}
kfree(s->s_options);
s->s_options = new_opt;
config.setuid = setuid;
config.setgid = setgid;
config.uid = uid;
config.gid = gid;
config.mode = mode;
return 0;
}
static struct super_operations capifs_sops =
{
.statfs = simple_statfs,
.remount_fs = capifs_remount,
.show_options = generic_show_options,
};
static int
capifs_fill_super(struct super_block *s, void *data, int silent)
{
struct inode * inode;
s->s_blocksize = 1024;
s->s_blocksize_bits = 10;
s->s_magic = CAPIFS_SUPER_MAGIC;
s->s_op = &capifs_sops;
s->s_time_gran = 1;
inode = new_inode(s);
if (!inode)
goto fail;
inode->i_ino = 1;
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
inode->i_blocks = 0;
inode->i_uid = inode->i_gid = 0;
inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO | S_IWUSR;
inode->i_op = &simple_dir_inode_operations;
inode->i_fop = &simple_dir_operations;
inode->i_nlink = 2;
capifs_root = s->s_root = d_alloc_root(inode);
if (s->s_root)
return 0;
printk("capifs: get root dentry failed\n");
iput(inode);
fail:
return -ENOMEM;
}
static int capifs_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, capifs_fill_super, mnt);
}
static struct file_system_type capifs_fs_type = {
.owner = THIS_MODULE,
.name = "capifs",
.get_sb = capifs_get_sb,
.kill_sb = kill_anon_super,
};
static struct dentry *get_node(int num)
{
char s[10];
struct dentry *root = capifs_root;
mutex_lock(&root->d_inode->i_mutex);
return lookup_one_len(s, root, sprintf(s, "%d", num));
}
void capifs_new_ncci(unsigned int number, dev_t device)
{
struct dentry *dentry;
struct inode *inode = new_inode(capifs_mnt->mnt_sb);
if (!inode)
return;
inode->i_ino = number+2;
inode->i_uid = config.setuid ? config.uid : current_fsuid();
inode->i_gid = config.setgid ? config.gid : current_fsgid();
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
init_special_inode(inode, S_IFCHR|config.mode, device);
//inode->i_op = &capifs_file_inode_operations;
dentry = get_node(number);
if (!IS_ERR(dentry) && !dentry->d_inode)
d_instantiate(dentry, inode);
mutex_unlock(&capifs_root->d_inode->i_mutex);
}
void capifs_free_ncci(unsigned int number)
{
struct dentry *dentry = get_node(number);
if (!IS_ERR(dentry)) {
struct inode *inode = dentry->d_inode;
if (inode) {
inode->i_nlink--;
d_delete(dentry);
dput(dentry);
}
dput(dentry);
}
mutex_unlock(&capifs_root->d_inode->i_mutex);
}
static int __init capifs_init(void)
{
char rev[32];
char *p;
int err;
if ((p = strchr(revision, ':')) != NULL && p[1]) {
strlcpy(rev, p + 2, sizeof(rev));
if ((p = strchr(rev, '$')) != NULL && p > rev)
*(p-1) = 0;
} else
strcpy(rev, "1.0");
err = register_filesystem(&capifs_fs_type);
if (!err) {
capifs_mnt = kern_mount(&capifs_fs_type);
if (IS_ERR(capifs_mnt)) {
err = PTR_ERR(capifs_mnt);
unregister_filesystem(&capifs_fs_type);
}
}
if (!err)
printk(KERN_NOTICE "capifs: Rev %s\n", rev);
return err;
}
static void __exit capifs_exit(void)
{
unregister_filesystem(&capifs_fs_type);
mntput(capifs_mnt);
}
EXPORT_SYMBOL(capifs_new_ncci);
EXPORT_SYMBOL(capifs_free_ncci);
module_init(capifs_init);
module_exit(capifs_exit);
|
