readahead.c 1.3 KB

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  1. /* Provide kernel hint to read ahead.
  2. Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc.
  3. This file is part of the GNU C Library.
  4. The GNU C Library is free software; you can redistribute it and/or
  5. modify it under the terms of the GNU Lesser General Public
  6. License as published by the Free Software Foundation; either
  7. version 2.1 of the License, or (at your option) any later version.
  8. The GNU C Library is distributed in the hope that it will be useful,
  9. but WITHOUT ANY WARRANTY; without even the implied warranty of
  10. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11. Lesser General Public License for more details.
  12. You should have received a copy of the GNU Lesser General Public
  13. License along with the GNU C Library; if not, see
  14. <http://www.gnu.org/licenses/>. */
  15. #include <sys/syscall.h>
  16. #if defined __NR_readahead && defined __UCLIBC_HAS_LFS__ && defined __USE_GNU
  17. # include <fcntl.h>
  18. # include <bits/wordsize.h>
  19. # if __WORDSIZE == 64
  20. _syscall3(ssize_t, readahead, int, fd, off_t, offset, size_t, count)
  21. # else
  22. ssize_t readahead(int fd, off64_t offset, size_t count)
  23. {
  24. return INLINE_SYSCALL(readahead,
  25. # if defined(__UCLIBC_SYSCALL_ALIGN_64BIT__)
  26. 5, fd, 0,
  27. # else
  28. 4, fd,
  29. # endif
  30. OFF64_HI_LO(offset), count);
  31. }
  32. # endif
  33. #endif