include/xfs_arch.h

   1 /*
   2  * Copyright (c) 2000-2002 Silicon Graphics, Inc.  All Rights Reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of version 2 of the GNU General Public License as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it would be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  11  *
  12  * Further, this software is distributed without any warranty that it is
  13  * free of the rightful claim of any third person regarding infringement
  14  * or the like.  Any license provided herein, whether implied or
  15  * otherwise, applies only to this software file.  Patent licenses, if
  16  * any, provided herein do not apply to combinations of this program with
  17  * other software, or any other product whatsoever.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, write the Free Software Foundation, Inc., 59
  21  * Temple Place - Suite 330, Boston MA 02111-1307, USA.
  22  *
  23  * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
  24  * Mountain View, CA  94043, or:
  25  *
  26  * http://www.sgi.com
  27  *
  28  * For further information regarding this notice, see:
  29  *
  30  * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
  31  */
  32 #ifndef __XFS_ARCH_H__
  33 #define __XFS_ARCH_H__
  34
  35 #ifndef XFS_BIG_FILESYSTEMS
  36 #error XFS_BIG_FILESYSTEMS must be defined true or false
  37 #endif
  38
  39 #ifdef __KERNEL__
  40
  41 #include <asm/byteorder.h>
  42
  43 #ifdef __LITTLE_ENDIAN
  44 # define __BYTE_ORDER   __LITTLE_ENDIAN
  45 #endif
  46 #ifdef __BIG_ENDIAN
  47 # define __BYTE_ORDER   __BIG_ENDIAN
  48 #endif
  49
  50 #endif  /* __KERNEL__ */
  51
  52 /* do we need conversion? */
  53
  54 #define ARCH_NOCONVERT 1
  55 #if __BYTE_ORDER == __LITTLE_ENDIAN
  56 #define ARCH_CONVERT   0
  57 #else
  58 #define ARCH_CONVERT   ARCH_NOCONVERT
  59 #endif
  60
  61 /* generic swapping macros */
  62
  63 #if defined(__linux__)
  64 #define INT_SWAP16(type,var) ((typeof(type))(__swab16((__u16)(var))))
  65 #define INT_SWAP32(type,var) ((typeof(type))(__swab32((__u32)(var))))
  66 #define INT_SWAP64(type,var) ((typeof(type))(__swab64((__u64)(var))))
  67 #endif
  68
  69 #define INT_SWAP(type, var) \
  70     ((sizeof(type) == 8) ? INT_SWAP64(type,var) : \
  71     ((sizeof(type) == 4) ? INT_SWAP32(type,var) : \
  72     ((sizeof(type) == 2) ? INT_SWAP16(type,var) : \
  73     (var))))
  74
  75 #define INT_SWAP_UNALIGNED_32(from,to) \
  76     { \
  77         ((__u8*)(to))[0] = ((__u8*)(from))[3]; \
  78         ((__u8*)(to))[1] = ((__u8*)(from))[2]; \
  79         ((__u8*)(to))[2] = ((__u8*)(from))[1]; \
  80         ((__u8*)(to))[3] = ((__u8*)(from))[0]; \
  81     }
  82
  83 #define INT_SWAP_UNALIGNED_64(from,to) \
  84     { \
  85         INT_SWAP_UNALIGNED_32( ((__u8*)(from)) + 4, ((__u8*)(to))); \
  86         INT_SWAP_UNALIGNED_32( ((__u8*)(from)), ((__u8*)(to)) + 4); \
  87     }
  88
  89 /*
  90  * get and set integers from potentially unaligned locations
  91  */
  92
  93 #define INT_GET_UNALIGNED_16_LE(pointer) \
  94    ((__u16)((((__u8*)(pointer))[0]      ) | (((__u8*)(pointer))[1] << 8 )))
  95 #define INT_GET_UNALIGNED_16_BE(pointer) \
  96    ((__u16)((((__u8*)(pointer))[0] << 8) | (((__u8*)(pointer))[1])))
  97 #define INT_SET_UNALIGNED_16_LE(pointer,value) \
  98     { \
  99         ((__u8*)(pointer))[0] = (((value)     ) & 0xff); \
 100         ((__u8*)(pointer))[1] = (((value) >> 8) & 0xff); \
 101     }
 102 #define INT_SET_UNALIGNED_16_BE(pointer,value) \
 103     { \
 104         ((__u8*)(pointer))[0] = (((value) >> 8) & 0xff); \
 105         ((__u8*)(pointer))[1] = (((value)     ) & 0xff); \
 106     }
 107
 108 #define INT_GET_UNALIGNED_32_LE(pointer) \
 109    ((__u32)((((__u8*)(pointer))[0]      ) | (((__u8*)(pointer))[1] << 8 ) \
 110            |(((__u8*)(pointer))[2] << 16) | (((__u8*)(pointer))[3] << 24)))
 111 #define INT_GET_UNALIGNED_32_BE(pointer) \
 112    ((__u32)((((__u8*)(pointer))[0] << 24) | (((__u8*)(pointer))[1] << 16) \
 113            |(((__u8*)(pointer))[2] << 8)  | (((__u8*)(pointer))[3]      )))
 114
 115 #define INT_GET_UNALIGNED_64_LE(pointer) \
 116    (((__u64)(INT_GET_UNALIGNED_32_LE(((__u8*)(pointer))+4)) << 32 ) \
 117    |((__u64)(INT_GET_UNALIGNED_32_LE(((__u8*)(pointer))  ))       ))
 118 #define INT_GET_UNALIGNED_64_BE(pointer) \
 119    (((__u64)(INT_GET_UNALIGNED_32_BE(((__u8*)(pointer))  )) << 32  ) \
 120    |((__u64)(INT_GET_UNALIGNED_32_BE(((__u8*)(pointer))+4))        ))
 121
 122 /*
 123  * now pick the right ones for our MACHINE ARCHITECTURE
 124  */
 125
 126 #if __BYTE_ORDER == __LITTLE_ENDIAN
 127 #define INT_GET_UNALIGNED_16(pointer)       INT_GET_UNALIGNED_16_LE(pointer)
 128 #define INT_SET_UNALIGNED_16(pointer,value) INT_SET_UNALIGNED_16_LE(pointer,value)
 129 #define INT_GET_UNALIGNED_32(pointer)       INT_GET_UNALIGNED_32_LE(pointer)
 130 #define INT_GET_UNALIGNED_64(pointer)       INT_GET_UNALIGNED_64_LE(pointer)
 131 #else
 132 #define INT_GET_UNALIGNED_16(pointer)       INT_GET_UNALIGNED_16_BE(pointer)
 133 #define INT_SET_UNALIGNED_16(pointer,value) INT_SET_UNALIGNED_16_BE(pointer,value)
 134 #define INT_GET_UNALIGNED_32(pointer)       INT_GET_UNALIGNED_32_BE(pointer)
 135 #define INT_GET_UNALIGNED_64(pointer)       INT_GET_UNALIGNED_64_BE(pointer)
 136 #endif
 137
 138 /* define generic INT_ macros */
 139
 140 #define INT_GET(reference,arch) \
 141     (((arch) == ARCH_NOCONVERT) \
 142         ? \
 143             (reference) \
 144         : \
 145             INT_SWAP((reference),(reference)) \
 146     )
 147
 148 /* does not return a value */
 149 #define INT_SET(reference,arch,valueref) \
 150     (__builtin_constant_p(valueref) ? \
 151         (void)( (reference) = ( ((arch) != ARCH_NOCONVERT) ? (INT_SWAP((reference),(valueref))) : (valueref)) ) : \
 152         (void)( \
 153             ((reference) = (valueref)), \
 154             ( ((arch) != ARCH_NOCONVERT) ? (reference) = INT_SWAP((reference),(reference)) : 0 ) \
 155         ) \
 156     )
 157
 158 /* does not return a value */
 159 #define INT_MOD_EXPR(reference,arch,code) \
 160     (void)(((arch) == ARCH_NOCONVERT) \
 161         ? \
 162             ((reference) code) \
 163         : \
 164             ( \
 165                 (reference) = INT_GET((reference),arch) , \
 166                 ((reference) code), \
 167                 INT_SET(reference, arch, reference) \
 168             ) \
 169     )
 170
 171 /* does not return a value */
 172 #define INT_MOD(reference,arch,delta) \
 173     (void)( \
 174         INT_MOD_EXPR(reference,arch,+=(delta)) \
 175     )
 176
 177 /*
 178  * INT_COPY - copy a value between two locations with the
 179  *            _same architecture_ but _potentially different sizes_
 180  *
 181  *          if the types of the two parameters are equal or they are
 182  *              in native architecture, a simple copy is done
 183  *
 184  *          otherwise, architecture conversions are done
 185  *
 186  */
 187
 188 /* does not return a value */
 189 #define INT_COPY(dst,src,arch) \
 190     (void)( \
 191         ((sizeof(dst) == sizeof(src)) || ((arch) == ARCH_NOCONVERT)) \
 192             ? \
 193                 ((dst) = (src)) \
 194             : \
 195                 INT_SET(dst, arch, INT_GET(src, arch)) \
 196     )
 197
 198 /*
 199  * INT_XLATE - copy a value in either direction between two locations
 200  *             with different architectures
 201  *
 202  *                  dir < 0     - copy from memory to buffer (native to arch)
 203  *                  dir > 0     - copy from buffer to memory (arch to native)
 204  */
 205
 206 /* does not return a value */
 207 #define INT_XLATE(buf,mem,dir,arch) {\
 208     ASSERT(dir); \
 209     if (dir>0) { \
 210         (mem)=INT_GET(buf, arch); \
 211     } else { \
 212         INT_SET(buf, arch, mem); \
 213     } \
 214 }
 215
 216 #define INT_ISZERO(reference,arch) \
 217     ((reference) == 0)
 218
 219 #define INT_ZERO(reference,arch) \
 220     ((reference) = 0)
 221
 222 #define INT_GET_UNALIGNED_16_ARCH(pointer,arch) \
 223     ( ((arch) == ARCH_NOCONVERT) \
 224         ? \
 225             (INT_GET_UNALIGNED_16(pointer)) \
 226         : \
 227             (INT_GET_UNALIGNED_16_BE(pointer)) \
 228     )
 229 #define INT_SET_UNALIGNED_16_ARCH(pointer,value,arch) \
 230     if ((arch) == ARCH_NOCONVERT) { \
 231         INT_SET_UNALIGNED_16(pointer,value); \
 232     } else { \
 233         INT_SET_UNALIGNED_16_BE(pointer,value); \
 234     }
 235
 236 #define DIRINO4_GET_ARCH(pointer,arch) \
 237     ( ((arch) == ARCH_NOCONVERT) \
 238         ? \
 239             (INT_GET_UNALIGNED_32(pointer)) \
 240         : \
 241             (INT_GET_UNALIGNED_32_BE(pointer)) \
 242     )
 243
 244 #if XFS_BIG_FILESYSTEMS
 245 #define DIRINO_GET_ARCH(pointer,arch) \
 246     ( ((arch) == ARCH_NOCONVERT) \
 247         ? \
 248             (INT_GET_UNALIGNED_64(pointer)) \
 249         : \
 250             (INT_GET_UNALIGNED_64_BE(pointer)) \
 251     )
 252 #else
 253 /* MACHINE ARCHITECTURE dependent */
 254 #if __BYTE_ORDER == __LITTLE_ENDIAN
 255 #define DIRINO_GET_ARCH(pointer,arch) \
 256     DIRINO4_GET_ARCH((((__u8*)pointer)+4),arch)
 257 #else
 258 #define DIRINO_GET_ARCH(pointer,arch) \
 259     DIRINO4_GET_ARCH(pointer,arch)
 260 #endif
 261 #endif
 262
 263 #define DIRINO_COPY_ARCH(from,to,arch) \
 264     if ((arch) == ARCH_NOCONVERT) { \
 265         memcpy(to,from,sizeof(xfs_ino_t)); \
 266     } else { \
 267         INT_SWAP_UNALIGNED_64(from,to); \
 268     }
 269 #define DIRINO4_COPY_ARCH(from,to,arch) \
 270     if ((arch) == ARCH_NOCONVERT) { \
 271         memcpy(to,(((__u8*)from+4)),sizeof(xfs_dir2_ino4_t)); \
 272     } else { \
 273         INT_SWAP_UNALIGNED_32(from,to); \
 274     }
 275
 276 #endif  /* __XFS_ARCH_H__ */