SYS.h revision 1.6 
1/*	$OpenBSD: SYS.h,v 1.6 2023/12/10 16:45:50 deraadt Exp $ */
2
3/*
4 * Copyright (c) 2016 Dale Rahn
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
16 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
19 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 *
27 */
28
29#include <machine/asm.h>
30#include <sys/syscall.h>
31
32#define PINSYSCALL(sysno, label)				\
33	.pushsection .openbsd.syscalls,"",@progbits		;\
34	.long label						;\
35	.long sysno						;\
36	.popsection
37
38#define SYSTRAP(x)						\
39	ldr	x8, =SYS_ ## x					;\
4099:	svc	0						;\
41	PINSYSCALL(SYS_ ## x, 99b)				;\
42	dsb	nsh						;\
43	isb
44
45#define DL_SYSCALL(n)						\
46	.global		__CONCAT(_dl_,n)			;\
47	.type		__CONCAT(_dl_,n)%function		;\
48__CONCAT(_dl_,n):						;\
49	RETGUARD_SETUP(__CONCAT(_dl_,n), x15)			;\
50	SYSTRAP(n)						;\
51	cneg	x0, x0, cs	/* r0 = -errno */		;\
52	RETGUARD_CHECK(__CONCAT(_dl_,n), x15)	 		;\
53	ret
54