blob: cd40352d52e33fb884d91a8d155f0fd303f90d9d [file] [log] [blame]
yuezonghe824eb0c2024-06-27 02:32:26 -07001/* 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
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
18 02111-1307 USA. */
19
20#include <errno.h>
21#include <fcntl.h>
22#include <sys/types.h>
23#include <sys/syscall.h>
24#include <bits/wordsize.h>
25
26#ifdef __UCLIBC_HAS_LFS__
27
28#include <_lfs_64.h>
29
30#ifdef __NR_readahead
31
32# define __NR___readahead __NR_readahead
33
34# if __WORDSIZE == 64
35
36static __inline__ _syscall3(ssize_t, __readahead, int, fd,
37 off_t, offset, size_t, count)
38
39ssize_t readahead(int fd, off_t offset, size_t count)
40{
41 return __readahead(fd, offset, count);
42}
43
44# else
45
46static __inline__ _syscall4(ssize_t, __readahead, int, fd,
47 off_t, high_offset, off_t, low_offset, size_t, count)
48
49ssize_t readahead(int fd, off64_t offset, size_t count)
50{
51 return __readahead(fd, (off_t) (offset >> 32), (off_t) (offset & 0xffffffff), count);
52}
53
54# endif
55
56#endif
57
58#endif /* __UCLIBC_HAS_LFS__ */