platform_bionic/libc/unistd/mmap.c
JP Abgrall b8e1e9685e bionic: pass MADV_MERGEABLE on private & anonymous mmaps
Change-Id: I8bc167bb33dec6417fe772172697ea6ff97da2f6
Signed-off-by: Iliyan Malchev <malchev@google.com>
2012-03-21 13:21:33 -07:00

50 lines
1.9 KiB
C

/*
* Copyright (C) 2008 The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <unistd.h>
#include <errno.h>
#include <sys/mman.h>
extern void* __mmap2(void*, size_t, int, int, int, size_t);
#define MMAP2_SHIFT 12
void* mmap(void *addr, size_t size, int prot, int flags, int fd, long offset)
{
void *ret;
if (offset & ((1UL << MMAP2_SHIFT)-1)) {
errno = EINVAL;
return MAP_FAILED;
}
ret = __mmap2(addr, size, prot, flags, fd, (size_t)offset >> MMAP2_SHIFT);
if (ret && (flags & (MAP_PRIVATE | MAP_ANONYMOUS)))
madvise(ret, size, MADV_MERGEABLE);
return ret;
}