include/linux/mtio.h

   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
  15 struct  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
  26 struct  mtpos32 {
  27         s32     mt_blkno;
  28 };
  29 #define MTIOCPOS32      _IOR('m', 3, struct mtpos32)
  30
  31 static 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         else
  47                 ret = copy_to_user(u, k, sizeof(*k));
  48
  49         return ret ? -EFAULT : 0;
  50 }
  51
  52 static 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