glibc/sysdeps/unix/sysv/linux/aarch64/syscall.S

45 lines
1.3 KiB
ArmAsm

/* Copyright (C) 2005-2015 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>
/* syscall (int nr, ...)
AArch64 system calls take between 0 and 7 arguments. On entry here nr
is in w0 and any other system call arguments are in register x1..x7.
For kernel entry we need to move the system call nr to x8 then
load the remaining arguments to register. */
ENTRY (syscall)
uxtw x8, w0
mov x0, x1
mov x1, x2
mov x2, x3
mov x3, x4
mov x4, x5
mov x5, x6
mov x6, x7
svc 0x0
cmn x0, #4095
b.cs 1f
RET
1:
b SYSCALL_ERROR
PSEUDO_END (syscall)