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1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef _LINUX_MTIO_COMPAT_H3#define _LINUX_MTIO_COMPAT_H4 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 tape11 * 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(u, &k32, sizeof(k32));46 else47 ret = copy_to_user(u, k, 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 else57 return put_user(k->mt_blkno, (long __user *)u);58}59 60#endif61