LXR linux-old/include/asm-mips64/ioctl.h

   1/*
   2 * This file is subject to the terms and conditions of the GNU General Public
   3 * License.  See the file "COPYING" in the main directory of this archive
   4 * for more details.
   5 *
   6 * Copyright (C) 1995, 1996, 1999, 2001 by Ralf Baechle
   7 */
   8#ifndef _ASM_IOCTL_H
   9#define _ASM_IOCTL_H
  10
  11/*
  12 * The original linux ioctl numbering scheme was just a general
  13 * "anything goes" setup, where more or less random numbers were
  14 * assigned.  Sorry, I was clueless when I started out on this.
  15 *
  16 * On the alpha, we'll try to clean it up a bit, using a more sane
  17 * ioctl numbering, and also trying to be compatible with OSF/1 in
  18 * the process. I'd like to clean it up for the i386 as well, but
  19 * it's so painful recognizing both the new and the old numbers..
  20 *
  21 * The same applies for for the MIPS ABI; in fact even the macros
  22 * from Linux/Alpha fit almost perfectly.
  23 */
  24
  25#define _IOC_NRBITS     8
  26#define _IOC_TYPEBITS   8
  27#define _IOC_SIZEBITS   13
  28#define _IOC_DIRBITS    3
  29
  30#define _IOC_NRMASK     ((1 << _IOC_NRBITS)-1)
  31#define _IOC_TYPEMASK   ((1 << _IOC_TYPEBITS)-1)
  32#define _IOC_SIZEMASK   ((1 << _IOC_SIZEBITS)-1)
  33#define _IOC_DIRMASK    ((1 << _IOC_DIRBITS)-1)
  34
  35#define _IOC_NRSHIFT    0
  36#define _IOC_TYPESHIFT  (_IOC_NRSHIFT+_IOC_NRBITS)
  37#define _IOC_SIZESHIFT  (_IOC_TYPESHIFT+_IOC_TYPEBITS)
  38#define _IOC_DIRSHIFT   (_IOC_SIZESHIFT+_IOC_SIZEBITS)
  39
  40/*
  41 * We to additionally limit parameters to a maximum 255 bytes.
  42 */
  43#define _IOC_SLMASK     0xff
  44
  45/*
  46 * Direction bits _IOC_NONE could be 0, but OSF/1 gives it a bit.
  47 * And this turns out useful to catch old ioctl numbers in header
  48 * files for us.
  49 */
  50#define _IOC_NONE       1U
  51#define _IOC_READ       2U
  52#define _IOC_WRITE      4U
  53
  54/*
  55 * The following are included for compatibility
  56 */
  57#define _IOC_VOID       0x20000000
  58#define _IOC_OUT        0x40000000
  59#define _IOC_IN         0x80000000
  60#define _IOC_INOUT      (IOC_IN|IOC_OUT)
  61
  62#define _IOC(dir,type,nr,size) \
  63        (((dir)  << _IOC_DIRSHIFT) | \
  64         ((type) << _IOC_TYPESHIFT) | \
  65         ((nr)   << _IOC_NRSHIFT) | \
  66         ((size) << _IOC_SIZESHIFT))
  67
  68/* used to create numbers */
  69#define _IO(type,nr)            _IOC(_IOC_NONE,(type),(nr),0)
  70#define _IOR(type,nr,size)      _IOC(_IOC_READ,(type),(nr),sizeof(size))
  71#define _IOW(type,nr,size)      _IOC(_IOC_WRITE,(type),(nr),sizeof(size))
  72#define _IOWR(type,nr,size)     _IOC(_IOC_READ|_IOC_WRITE,(type),(nr),sizeof(size))
  73
  74/* used to decode them.. */
  75#define _IOC_DIR(nr)            (((nr) >> _IOC_DIRSHIFT) & _IOC_DIRMASK)
  76#define _IOC_TYPE(nr)           (((nr) >> _IOC_TYPESHIFT) & _IOC_TYPEMASK)
  77#define _IOC_NR(nr)             (((nr) >> _IOC_NRSHIFT) & _IOC_NRMASK)
  78#define _IOC_SIZE(nr)           (((nr) >> _IOC_SIZESHIFT) & _IOC_SIZEMASK)
  79
  80/* ...and for the drivers/sound files... */
  81
  82#define IOC_IN          (_IOC_WRITE << _IOC_DIRSHIFT)
  83#define IOC_OUT         (_IOC_READ << _IOC_DIRSHIFT)
  84#define IOC_INOUT       ((_IOC_WRITE|_IOC_READ) << _IOC_DIRSHIFT)
  85#define IOCSIZE_MASK    (_IOC_SIZEMASK << _IOC_SIZESHIFT)
  86#define IOCSIZE_SHIFT   (_IOC_SIZESHIFT)
  87
  88#endif /* _ASM_IOCTL_H */
  89