1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_MTIO_COMPAT_H
3#define _LINUX_MTIO_COMPAT_H
4
5#include <linux/compat.h>
6#include <uapi/linux/mtio.h>
7#include <linux/uaccess.h>
8
9/*
10 * helper functions for implementing compat ioctls on the four tape
11 * drivers: we define the 32-bit layout of each incompatible structure,
12 * plus a wrapper function to copy it to user space in either format.
13 */
14
15struct mtget32 {
16 s32 mt_type;
17 s32 mt_resid;
18 s32 mt_dsreg;
19 s32 mt_gstat;
20 s32 mt_erreg;
21 s32 mt_fileno;
22 s32 mt_blkno;
23};
24#define MTIOCGET32 _IOR('m', 2, struct mtget32)
25
26struct mtpos32 {
27 s32 mt_blkno;
28};
29#define MTIOCPOS32 _IOR('m', 3, struct mtpos32)
30
31static inline int put_user_mtget(void __user *u, struct mtget *k)
32{
33 struct mtget32 k32 = {
34 .mt_type = k->mt_type,
35 .mt_resid = k->mt_resid,
36 .mt_dsreg = k->mt_dsreg,
37 .mt_gstat = k->mt_gstat,
38 .mt_erreg = k->mt_erreg,
39 .mt_fileno = k->mt_fileno,
40 .mt_blkno = k->mt_blkno,
41 };
42 int ret;
43
44 if (in_compat_syscall())
45 ret = copy_to_user(to: u, from: &k32, n: sizeof(k32));
46 else
47 ret = copy_to_user(to: u, from: k, n: sizeof(*k));
48
49 return ret ? -EFAULT : 0;
50}
51
52static inline int put_user_mtpos(void __user *u, struct mtpos *k)
53{
54 if (in_compat_syscall())
55 return put_user(k->mt_blkno, (u32 __user *)u);
56 else
57 return put_user(k->mt_blkno, (long __user *)u);
58}
59
60#endif
61

source code of linux/include/linux/mtio.h