1  /* Copyright (C) 2003-2023 Free Software Foundation, Inc.
       2     This file is part of the GNU C Library.
       3  
       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  
       9     The GNU C Library 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 the GNU
      12     Lesser General Public License for more details.
      13  
      14     You should have received a copy of the GNU Lesser General Public
      15     License along with the GNU C Library; if not, see
      16     <https://www.gnu.org/licenses/>.  */
      17  
      18  #include <errno.h>
      19  #include <fcntl.h>
      20  #include <sysdep.h>
      21  
      22  /* Advice the system about the expected behaviour of the application with
      23     respect to the file associated with FD.  */
      24  
      25  #ifndef __OFF_T_MATCHES_OFF64_T
      26  
      27  /* Default implementation will use __NR_fadvise64 with expected argument
      28     positions (for instance i386 and powerpc32 that uses __ALIGNMENT_ARG).
      29  
      30     Second option will be used by arm which define __NR_arm_fadvise64_64
      31     (redefined to __NR_fadvise64_64 in kernel-features.h) that behaves as
      32     __NR_fadvise64_64 (without the alignment argument required for the ABI).
      33  
      34     Third option will be used by mips o32.  Mips will use a 7 argument
      35     syscall with __NR_fadvise64.
      36  
      37     s390 implements fadvice64_64 using a specific struct with arguments
      38     packed inside.  This is the only implementation handled in arch-specific
      39     code.  */
      40  
      41  int
      42  posix_fadvise (int fd, off_t offset, off_t len, int advise)
      43  {
      44  # if defined (__NR_fadvise64) && !defined (__ASSUME_FADVISE64_AS_64_64)
      45    int ret = INTERNAL_SYSCALL_CALL (fadvise64, fd,
      46  				   __ALIGNMENT_ARG SYSCALL_LL (offset),
      47  				   len, advise);
      48  # else
      49  #  ifdef __ASSUME_FADVISE64_64_6ARG
      50    int ret = INTERNAL_SYSCALL_CALL (fadvise64_64, fd, advise,
      51  				   SYSCALL_LL (offset), SYSCALL_LL (len));
      52  #  else
      53  
      54  #   ifndef __NR_fadvise64_64
      55  #    define __NR_fadvise64_64 __NR_fadvise64
      56  #   endif
      57  
      58    int ret = INTERNAL_SYSCALL_CALL (fadvise64_64, fd,
      59  				   __ALIGNMENT_ARG SYSCALL_LL (offset),
      60  				   SYSCALL_LL (len), advise);
      61  #  endif
      62  # endif
      63    if (INTERNAL_SYSCALL_ERROR_P (ret))
      64      return INTERNAL_SYSCALL_ERRNO (ret);
      65    return 0;
      66  }
      67  #endif /* __OFF_T_MATCHES_OFF64_T  */