FreeBSD/Linux Kernel Cross Reference
sys/include/asm-mips64/ioctl.h

     /*
      * This file is subject to the terms and conditions of the GNU General Public
      * License.  See the file "COPYING" in the main directory of this archive
      * for more details.
      *
      * Copyright (C) 1995, 1996, 1999, 2001 by Ralf Baechle
      */
     #ifndef _ASM_IOCTL_H
     #define _ASM_IOCTL_H
    
    /*
     * The original linux ioctl numbering scheme was just a general
     * "anything goes" setup, where more or less random numbers were
     * assigned.  Sorry, I was clueless when I started out on this.
     *
     * On the alpha, we'll try to clean it up a bit, using a more sane
     * ioctl numbering, and also trying to be compatible with OSF/1 in
     * the process. I'd like to clean it up for the i386 as well, but
     * it's so painful recognizing both the new and the old numbers..
     *
     * The same applies for for the MIPS ABI; in fact even the macros
     * from Linux/Alpha fit almost perfectly.
     */
    
    #define _IOC_NRBITS     8
    #define _IOC_TYPEBITS   8
    #define _IOC_SIZEBITS   13
    #define _IOC_DIRBITS    3
    
    #define _IOC_NRMASK     ((1 << _IOC_NRBITS)-1)
    #define _IOC_TYPEMASK   ((1 << _IOC_TYPEBITS)-1)
    #define _IOC_SIZEMASK   ((1 << _IOC_SIZEBITS)-1)
    #define _IOC_DIRMASK    ((1 << _IOC_DIRBITS)-1)
    
    #define _IOC_NRSHIFT    0
    #define _IOC_TYPESHIFT  (_IOC_NRSHIFT+_IOC_NRBITS)
    #define _IOC_SIZESHIFT  (_IOC_TYPESHIFT+_IOC_TYPEBITS)
    #define _IOC_DIRSHIFT   (_IOC_SIZESHIFT+_IOC_SIZEBITS)
    
    /*
     * We to additionally limit parameters to a maximum 255 bytes.
     */
    #define _IOC_SLMASK     0xff
    
    /*
     * Direction bits _IOC_NONE could be 0, but OSF/1 gives it a bit.
     * And this turns out useful to catch old ioctl numbers in header
     * files for us.
     */
    #define _IOC_NONE       1U
    #define _IOC_READ       2U
    #define _IOC_WRITE      4U
    
    /*
     * The following are included for compatibility
     */
    #define _IOC_VOID       0x20000000
    #define _IOC_OUT        0x40000000
    #define _IOC_IN         0x80000000
    #define _IOC_INOUT      (IOC_IN|IOC_OUT)
    
    #define _IOC(dir,type,nr,size) \
            (((dir)  << _IOC_DIRSHIFT) | \
             ((type) << _IOC_TYPESHIFT) | \
             ((nr)   << _IOC_NRSHIFT) | \
             ((size) << _IOC_SIZESHIFT))
    
    /* used to create numbers */
    #define _IO(type,nr)            _IOC(_IOC_NONE,(type),(nr),0)
    #define _IOR(type,nr,size)      _IOC(_IOC_READ,(type),(nr),sizeof(size))
    #define _IOW(type,nr,size)      _IOC(_IOC_WRITE,(type),(nr),sizeof(size))
    #define _IOWR(type,nr,size)     _IOC(_IOC_READ|_IOC_WRITE,(type),(nr),sizeof(size))
    
    /* used to decode them.. */
    #define _IOC_DIR(nr)            (((nr) >> _IOC_DIRSHIFT) & _IOC_DIRMASK)
    #define _IOC_TYPE(nr)           (((nr) >> _IOC_TYPESHIFT) & _IOC_TYPEMASK)
    #define _IOC_NR(nr)             (((nr) >> _IOC_NRSHIFT) & _IOC_NRMASK)
    #define _IOC_SIZE(nr)           (((nr) >> _IOC_SIZESHIFT) & _IOC_SIZEMASK)
    
    /* ...and for the drivers/sound files... */
    
    #define IOC_IN          (_IOC_WRITE << _IOC_DIRSHIFT)
    #define IOC_OUT         (_IOC_READ << _IOC_DIRSHIFT)
    #define IOC_INOUT       ((_IOC_WRITE|_IOC_READ) << _IOC_DIRSHIFT)
    #define IOCSIZE_MASK    (_IOC_SIZEMASK << _IOC_SIZESHIFT)
    #define IOCSIZE_SHIFT   (_IOC_SIZESHIFT)
    
    #endif /* _ASM_IOCTL_H */

Cache object: 1ae2aa5a6fd8e1d8a54d9793000853a4