libc/sysdeps/linux/common/posix_fadvise.c

   1 /*
   2  * posix_fadvise() for uClibc
   3  * http://www.opengroup.org/onlinepubs/009695399/functions/posix_fadvise.html
   4  *
   5  * Copyright (C) 2000-2006 Erik Andersen <[email protected]>
   6  *
   7  * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
   8  */
   9
  10 #include <sys/syscall.h>
  11
  12 #ifdef __NR_arm_fadvise64_64
  13 /* We handle the 64bit alignment issue which is why the arm guys renamed their
  14  * syscall in the first place.  So rename it back.
  15  */
  16 # define __NR_fadvise64_64 __NR_arm_fadvise64_64
  17 #endif
  18
  19 #if defined(__NR_fadvise64) || defined(__NR_fadvise64_64)
  20 # include <fcntl.h>
  21 # include <endian.h>
  22 # include <bits/wordsize.h>
  23
  24 # if defined(__NR_fadvise64_64)
  25 #include <_lfs_64.h>
  26
  27 int posix_fadvise64(int fd, off64_t offset, off64_t len, int advice);
  28 int posix_fadvise(int fd, off_t offset, off_t len, int advice)
  29 {
  30         return posix_fadvise64(fd, offset, len, advice);
  31 }
  32 #else
  33
  34 int posix_fadvise(int fd, off_t offset, off_t len, int advice)
  35 {
  36         int ret;
  37         INTERNAL_SYSCALL_DECL(err);
  38
  39 # ifdef __NR_fadvise64_64
  40 #  if __WORDSIZE == 64
  41         ret = INTERNAL_SYSCALL(fadvise64_64, err, 4, fd, offset, len, advice);
  42 #  else
  43 #   if defined (__arm__) || defined (__nds32__) || defined(__csky__) || \
  44       (defined(__UCLIBC_SYSCALL_ALIGN_64BIT__) && (defined(__powerpc__) || defined(__xtensa__)))
  45         /* arch with 64-bit data in even reg alignment #1: [powerpc/xtensa]
  46          * custom syscall handler (rearranges @advice to avoid register hole punch) */
  47         ret = INTERNAL_SYSCALL(fadvise64_64, err, 6, fd, advice,
  48                         OFF_HI_LO (offset), OFF_HI_LO (len));
  49 #   elif defined(__UCLIBC_SYSCALL_ALIGN_64BIT__)
  50         /* arch with 64-bit data in even reg alignment #2: [arcv2/others-in-future]
  51          * stock syscall handler in kernel (reg hole punched) */
  52         ret = INTERNAL_SYSCALL(fadvise64_64, err, 7, fd, 0,
  53                         OFF_HI_LO (offset), OFF_HI_LO (len), advice);
  54 #   else
  55         ret = INTERNAL_SYSCALL(fadvise64_64, err, 6, fd,
  56                         OFF_HI_LO (offset), OFF_HI_LO (len), advice);
  57 #   endif
  58 #  endif
  59 # else  /* __NR_fadvise64 */
  60 #  if __WORDSIZE == 64
  61         ret = INTERNAL_SYSCALL(fadvise64, err, 4, fd, offset, len, advice);
  62 #  else
  63 #   if defined(__UCLIBC_SYSCALL_ALIGN_64BIT__)
  64         ret = INTERNAL_SYSCALL(fadvise64, err, 6, fd, /*unused*/0,
  65 #   else
  66         ret = INTERNAL_SYSCALL(fadvise64, err, 5, fd,
  67 #   endif
  68                         OFF_HI_LO (offset), len, advice);
  69 #  endif
  70 #  endif
  71         if (INTERNAL_SYSCALL_ERROR_P (ret, err))
  72                 return INTERNAL_SYSCALL_ERRNO (ret, err);
  73         return 0;
  74 }
  75 # if !defined __NR_fadvise64_64 || __WORDSIZE == 64
  76 strong_alias(posix_fadvise,posix_fadvise64)
  77 # endif
  78 #endif
  79 #endif