release/src-rt-6.x.4708/linux/linux-2.6.36/fs/jfs/endian24.h

   1 /*
   2  *   Copyright (C) International Business Machines Corp., 2001
   3  *
   4  *   This program is free software;  you can redistribute it and/or modify
   5  *   it under the terms of the GNU General Public License as published by
   6  *   the Free Software Foundation; either version 2 of the License, or
   7  *   (at your option) any later version.
   8  *
   9  *   This program is distributed in the hope that it will be useful,
  10  *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
  11  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  12  *   the GNU General Public License for more details.
  13  *
  14  *   You should have received a copy of the GNU General Public License
  15  *   along with this program;  if not, write to the Free Software
  16  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  17  */
  18 #ifndef _H_ENDIAN24
  19 #define _H_ENDIAN24
  20
  21 /*
  22  *      endian24.h:
  23  *
  24  * Endian conversion for 24-byte data
  25  *
  26  */
  27 #define __swab24(x) \
  28 ({ \
  29         __u32 __x = (x); \
  30         ((__u32)( \
  31                 ((__x & (__u32)0x000000ffUL) << 16) | \
  32                  (__x & (__u32)0x0000ff00UL)        | \
  33                 ((__x & (__u32)0x00ff0000UL) >> 16) )); \
  34 })
  35
  36 #if (defined(__KERNEL__) && defined(__LITTLE_ENDIAN)) || (defined(__BYTE_ORDER) && \
  37         (__BYTE_ORDER == __LITTLE_ENDIAN))
  38         #define __cpu_to_le24(x) ((__u32)(x))
  39         #define __le24_to_cpu(x) ((__u32)(x))
  40 #else
  41         #define __cpu_to_le24(x) __swab24(x)
  42         #define __le24_to_cpu(x) __swab24(x)
  43 #endif
  44
  45 #ifdef __KERNEL__
  46         #define cpu_to_le24 __cpu_to_le24
  47         #define le24_to_cpu __le24_to_cpu
  48 #endif
  49
  50 #endif                          /* !_H_ENDIAN24 */