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
|
// SPDX-License-Identifier: GPL-2.0
/*
* IOCTL interface for SCLP
*
* Copyright IBM Corp. 2012
*
* Author: Michael Holzheu <holzheu@linux.vnet.ibm.com>
*/
#include <linux/compat.h>
#include <linux/uaccess.h>
#include <linux/miscdevice.h>
#include <linux/gfp.h>
#include <linux/init.h>
#include <linux/ioctl.h>
#include <linux/fs.h>
#include <asm/compat.h>
#include <asm/sclp_ctl.h>
#include <asm/sclp.h>
#include "sclp.h"
/*
* Supported command words
*/
static unsigned int sclp_ctl_sccb_wlist[] = {
0x00400002,
0x00410002,
};
/*
* Check if command word is supported
*/
static int sclp_ctl_cmdw_supported(unsigned int cmdw)
{
int i;
for (i = 0; i < ARRAY_SIZE(sclp_ctl_sccb_wlist); i++) {
if (cmdw == sclp_ctl_sccb_wlist[i])
return 1;
}
return 0;
}
static void __user *u64_to_uptr(u64 value)
{
if (is_compat_task())
return compat_ptr(value);
else
return (void __user *)(unsigned long)value;
}
/*
* Start SCLP request
*/
static int sclp_ctl_ioctl_sccb(void __user *user_area)
{
struct sclp_ctl_sccb ctl_sccb;
struct sccb_header *sccb;
unsigned long copied;
int rc;
if (copy_from_user(&ctl_sccb, user_area, sizeof(ctl_sccb)))
return -EFAULT;
if (!sclp_ctl_cmdw_supported(ctl_sccb.cmdw))
return -EOPNOTSUPP;
sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
if (!sccb)
return -ENOMEM;
copied = PAGE_SIZE -
copy_from_user(sccb, u64_to_uptr(ctl_sccb.sccb), PAGE_SIZE);
if (offsetof(struct sccb_header, length) +
sizeof(sccb->length) > copied || sccb->length > copied) {
rc = -EFAULT;
goto out_free;
}
if (sccb->length < 8) {
rc = -EINVAL;
goto out_free;
}
rc = sclp_sync_request(ctl_sccb.cmdw, sccb);
if (rc)
goto out_free;
if (copy_to_user(u64_to_uptr(ctl_sccb.sccb), sccb, sccb->length))
rc = -EFAULT;
out_free:
free_page((unsigned long) sccb);
return rc;
}
/*
* SCLP SCCB ioctl function
*/
static long sclp_ctl_ioctl(struct file *filp, unsigned int cmd,
unsigned long arg)
{
void __user *argp;
if (is_compat_task())
argp = compat_ptr(arg);
else
argp = (void __user *) arg;
switch (cmd) {
case SCLP_CTL_SCCB:
return sclp_ctl_ioctl_sccb(argp);
default: /* unknown ioctl number */
return -ENOTTY;
}
}
/*
* File operations
*/
static const struct file_operations sclp_ctl_fops = {
.owner = THIS_MODULE,
.open = nonseekable_open,
.unlocked_ioctl = sclp_ctl_ioctl,
.compat_ioctl = sclp_ctl_ioctl,
.llseek = no_llseek,
};
/*
* Misc device definition
*/
static struct miscdevice sclp_ctl_device = {
.minor = MISC_DYNAMIC_MINOR,
.name = "sclp",
.fops = &sclp_ctl_fops,
};
builtin_misc_device(sclp_ctl_device);
|
