include/asm-powerpc/ioctl.h

   1 #ifndef _PPC_IOCTL_H
   2 #define _PPC_IOCTL_H
   3
   4
   5 /*
   6  * this was copied from the alpha as it's a bit cleaner there.
   7  *                         -- Cort
   8  */
   9
  10 #define _IOC_NRBITS     8
  11 #define _IOC_TYPEBITS   8
  12 #define _IOC_SIZEBITS   13
  13 #define _IOC_DIRBITS    3
  14
  15 #define _IOC_NRMASK     ((1 << _IOC_NRBITS)-1)
  16 #define _IOC_TYPEMASK   ((1 << _IOC_TYPEBITS)-1)
  17 #define _IOC_SIZEMASK   ((1 << _IOC_SIZEBITS)-1)
  18 #define _IOC_DIRMASK    ((1 << _IOC_DIRBITS)-1)
  19
  20 #define _IOC_NRSHIFT    0
  21 #define _IOC_TYPESHIFT  (_IOC_NRSHIFT+_IOC_NRBITS)
  22 #define _IOC_SIZESHIFT  (_IOC_TYPESHIFT+_IOC_TYPEBITS)
  23 #define _IOC_DIRSHIFT   (_IOC_SIZESHIFT+_IOC_SIZEBITS)
  24
  25 /*
  26  * Direction bits _IOC_NONE could be 0, but OSF/1 gives it a bit.
  27  * And this turns out useful to catch old ioctl numbers in header
  28  * files for us.
  29  */
  30 #define _IOC_NONE       1U
  31 #define _IOC_READ       2U
  32 #define _IOC_WRITE      4U
  33
  34 #define _IOC(dir,type,nr,size) \
  35         (((dir)  << _IOC_DIRSHIFT) | \
  36          ((type) << _IOC_TYPESHIFT) | \
  37          ((nr)   << _IOC_NRSHIFT) | \
  38          ((size) << _IOC_SIZESHIFT))
  39
  40 /* provoke compile error for invalid uses of size argument */
  41 extern unsigned int __invalid_size_argument_for_IOC;
  42 #define _IOC_TYPECHECK(t) \
  43         ((sizeof(t) == sizeof(t[1]) && \
  44           sizeof(t) < (1 << _IOC_SIZEBITS)) ? \
  45           sizeof(t) : __invalid_size_argument_for_IOC)
  46
  47 /* used to create numbers */
  48 #define _IO(type,nr)            _IOC(_IOC_NONE,(type),(nr),0)
  49 #define _IOR(type,nr,size)      _IOC(_IOC_READ,(type),(nr),(_IOC_TYPECHECK(size)))
  50 #define _IOW(type,nr,size)      _IOC(_IOC_WRITE,(type),(nr),(_IOC_TYPECHECK(size)))
  51 #define _IOWR(type,nr,size)     _IOC(_IOC_READ|_IOC_WRITE,(type),(nr),(_IOC_TYPECHECK(size)))
  52 #define _IOR_BAD(type,nr,size)  _IOC(_IOC_READ,(type),(nr),sizeof(size))
  53 #define _IOW_BAD(type,nr,size)  _IOC(_IOC_WRITE,(type),(nr),sizeof(size))
  54 #define _IOWR_BAD(type,nr,size) _IOC(_IOC_READ|_IOC_WRITE,(type),(nr),sizeof(size))
  55
  56 /* used to decode them.. */
  57 #define _IOC_DIR(nr)            (((nr) >> _IOC_DIRSHIFT) & _IOC_DIRMASK)
  58 #define _IOC_TYPE(nr)           (((nr) >> _IOC_TYPESHIFT) & _IOC_TYPEMASK)
  59 #define _IOC_NR(nr)             (((nr) >> _IOC_NRSHIFT) & _IOC_NRMASK)
  60 #define _IOC_SIZE(nr)           (((nr) >> _IOC_SIZESHIFT) & _IOC_SIZEMASK)
  61
  62 /* various drivers, such as the pcmcia stuff, need these... */
  63 #define IOC_IN          (_IOC_WRITE << _IOC_DIRSHIFT)
  64 #define IOC_OUT         (_IOC_READ << _IOC_DIRSHIFT)
  65 #define IOC_INOUT       ((_IOC_WRITE|_IOC_READ) << _IOC_DIRSHIFT)
  66 #define IOCSIZE_MASK    (_IOC_SIZEMASK << _IOC_SIZESHIFT)
  67 #define IOCSIZE_SHIFT   (_IOC_SIZESHIFT)
  68
  69 #endif