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
|
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
*/
#include <linux/ctype.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/types.h>
#include <linux/uaccess.h>
/*
* If read and write race, the read will still atomically read a valid
* value.
*/
int uml_exitcode = 0;
static int exitcode_proc_show(struct seq_file *m, void *v)
{
int val;
/*
* Save uml_exitcode in a local so that we don't need to guarantee
* that sprintf accesses it atomically.
*/
val = uml_exitcode;
seq_printf(m, "%d\n", val);
return 0;
}
static int exitcode_proc_open(struct inode *inode, struct file *file)
{
return single_open(file, exitcode_proc_show, NULL);
}
static ssize_t exitcode_proc_write(struct file *file,
const char __user *buffer, size_t count, loff_t *pos)
{
char *end, buf[sizeof("nnnnn\0")];
size_t size;
int tmp;
size = min(count, sizeof(buf));
if (copy_from_user(buf, buffer, size))
return -EFAULT;
tmp = simple_strtol(buf, &end, 0);
if ((*end != '\0') && !isspace(*end))
return -EINVAL;
uml_exitcode = tmp;
return count;
}
static const struct proc_ops exitcode_proc_ops = {
.proc_open = exitcode_proc_open,
.proc_read = seq_read,
.proc_lseek = seq_lseek,
.proc_release = single_release,
.proc_write = exitcode_proc_write,
};
static int make_proc_exitcode(void)
{
struct proc_dir_entry *ent;
ent = proc_create("exitcode", 0600, NULL, &exitcode_proc_ops);
if (ent == NULL) {
printk(KERN_WARNING "make_proc_exitcode : Failed to register "
"/proc/exitcode\n");
return 0;
}
return 0;
}
__initcall(make_proc_exitcode);
|
