glibc/sysdeps/unix/sysv/linux/i386/mmap.S
2012-02-09 23:18:22 +00:00

107 lines
2.4 KiB
ArmAsm

/* Copyright (C) 1995,96,97,98,99,2000,2002,2005,2006
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, see
<http://www.gnu.org/licenses/>. */
#include <sysdep.h>
#include <kernel-features.h>
#define EINVAL 22
.text
ENTRY (__mmap)
/* I don't think it is worthwhile trying to use mmap2 whenever it
is available. Only use it when we are sure the syscall exists. */
#ifdef __ASSUME_MMAP2_SYSCALL
/* Save registers. */
pushl %ebp
cfi_adjust_cfa_offset (4)
pushl %ebx
cfi_adjust_cfa_offset (4)
pushl %esi
cfi_adjust_cfa_offset (4)
pushl %edi
cfi_adjust_cfa_offset (4)
movl 20(%esp), %ebx
cfi_rel_offset (ebx, 8)
movl 24(%esp), %ecx
movl 28(%esp), %edx
movl 32(%esp), %esi
cfi_rel_offset (esi, 4)
movl 36(%esp), %edi
cfi_rel_offset (edi, 0)
movl 40(%esp), %ebp
cfi_rel_offset (ebp, 12)
testl $0xfff, %ebp
movl $-EINVAL, %eax
jne L(skip)
shrl $12, %ebp /* mmap2 takes the offset in pages. */
movl $SYS_ify(mmap2), %eax /* System call number in %eax. */
/* Do the system call trap. */
ENTER_KERNEL
L(skip):
/* Restore registers. */
popl %edi
cfi_adjust_cfa_offset (-4)
cfi_restore (edi)
popl %esi
cfi_adjust_cfa_offset (-4)
cfi_restore (esi)
popl %ebx
cfi_adjust_cfa_offset (-4)
cfi_restore (ebx)
popl %ebp
cfi_adjust_cfa_offset (-4)
cfi_restore (ebp)
#else
/* Save registers. */
movl %ebx, %edx
cfi_register (ebx, edx)
movl $SYS_ify(mmap), %eax /* System call number in %eax. */
lea 4(%esp), %ebx /* Address of args is 1st arg. */
/* Do the system call trap. */
int $0x80
/* Restore registers. */
movl %edx, %ebx
cfi_restore (ebx)
#endif
/* If 0 > %eax > -4096 there was an error. */
cmpl $-4096, %eax
ja SYSCALL_ERROR_LABEL
/* Successful; return the syscall's value. */
L(pseudo_end):
ret
PSEUDO_END (__mmap)
weak_alias (__mmap, mmap)