1/* Copyright (C) 2007-2020 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 <sysdep.h>
19#include <sys/mman.h>
20
21
22int
23posix_madvise (void *addr, size_t len, int advice)
24{
25 /* We have one problem: the kernel's MADV_DONTNEED does not
26 correspond to POSIX's POSIX_MADV_DONTNEED. The former simply
27 discards changes made to the memory without writing it back to
28 disk, if this would be necessary. The POSIX behavior does not
29 allow this. There is no functionality mapping the POSIX behavior
30 so far so we ignore that advice for now. */
31 if (advice == POSIX_MADV_DONTNEED)
32 return 0;
33
34 int result = INTERNAL_SYSCALL_CALL (madvise, addr, len, advice);
35 return INTERNAL_SYSCALL_ERRNO (result);
36}
37