diff options
Diffstat (limited to 'libc/sysdeps')
-rw-r--r-- | libc/sysdeps/linux/common/readahead.c | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/libc/sysdeps/linux/common/readahead.c b/libc/sysdeps/linux/common/readahead.c new file mode 100644 index 000000000..5220b5dc4 --- /dev/null +++ b/libc/sysdeps/linux/common/readahead.c @@ -0,0 +1,52 @@ +/* Provide kernel hint to read ahead. + Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <errno.h> +#include <fcntl.h> +#include <sys/types.h> +#include <sys/syscall.h> +#include <bits/wordsize.h> + +#ifdef __NR_readahead + +# define __NR___readahead __NR_readahead + +# if __WORDSIZE == 64 + +static inline _syscall3(ssize_t, __readahead, int, fd, + off_t, offset, size_t, count); + +ssize_t readahead(int fd, off_t offset, size_t count) +{ + return __readahead(fd, offset, count); +} + +# else + +static inline _syscall4(ssize_t, __readahead, int, fd, + off_t, high_offset, off_t, low_offset, size_t, count); + +ssize_t readahead(int fd, off64_t offset, size_t count) +{ + return __readahead(fd, (off_t) (offset >> 32), (off_t) (offset & 0xffffffff), count); +} + +# endif + +#endif |