xref: /netbsd-src/sys/arch/aarch64/aarch64/linux32_syscall.c (revision 2f5e5e735694c180714bb1b7faa48b23eb56b861)
1 /*	$NetBSD: linux32_syscall.c,v 1.1 2021/11/25 03:08:04 ryo Exp $	*/
2 
3 /*-
4  * Copyright (c) 2021 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Ryo Shimizu.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: linux32_syscall.c,v 1.1 2021/11/25 03:08:04 ryo Exp $");
34 
35 #if defined(_KERNEL_OPT)
36 #include "opt_compat_linux32.h"
37 #endif
38 
39 #include <sys/param.h>
40 #include <sys/types.h>
41 
42 #include <compat/linux32/linux32_syscall.h>
43 #include <compat/linux32/common/linux32_errno.h>
44 
45 #define EMULNAME(x)		__CONCAT(linux32_,x)
46 #define EMULNAMEU(x)		__CONCAT(LINUX32_,x)
47 
48 /*
49  * syscall.c behavior options
50  */
51 
52 /*
53  * EABI linux/arm always uses indirect syscall, and code of 'svc #<code>' must
54  * be zero. The system call number is specified by the r7 register.
55  */
56 #define NARGREG			7 /* Seven(all) arguments are passed in r0-r6 */
57 #define SYSCALL_CODE_REG	7 /* syscall number is passed in r7 */
58 #define SYSCALL_CODE_REG_SVC	0 /* Non-zero is OABI, but not supported */
59 #define SYSCALL_NO_INDIRECT
60 
61 /* used when __HAVE_MINIMAL_EMUL is not defined */
62 #define SYSCALL_EMUL_ERRNO(x)	native_to_linux32_errno[x]
63 
64 /* don't update x1 register with rval[1] */
65 #define SYSCALL_NO_RVAL1
66 
67 #define SYSCALL_CODE_REMAP(code)	linux32_syscall_code_remap(code)
68 
69 /*
70  * see also comments in the bottom of
71  * sys/compat/linux32/arch/aarch64/syscalls.master
72  */
73 #define LINUX32_EARM_NR_BASE		0x0f0000
74 #define LINUX32_SYS_ARMBASE		480
75 
76 static inline uint32_t
linux32_syscall_code_remap(uint32_t code)77 linux32_syscall_code_remap(uint32_t code)
78 {
79 	if (code > LINUX32_EARM_NR_BASE)
80 		code = code - LINUX32_EARM_NR_BASE + LINUX32_SYS_ARMBASE;
81 	return code;
82 }
83 
84 #include "aarch32_syscall.c"
85