tools/include/nolibc/arch-aarch64.h


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200

/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
/*
 * AARCH64 specific definitions for NOLIBC
 * Copyright (C) 2017-2022 Willy Tarreau <w@1wt.eu>
 */

#ifndef _NOLIBC_ARCH_AARCH64_H
#define _NOLIBC_ARCH_AARCH64_H

/* O_* macros for fcntl/open are architecture-specific */
#define O_RDONLY            0
#define O_WRONLY            1
#define O_RDWR              2
#define O_CREAT          0x40
#define O_EXCL           0x80
#define O_NOCTTY        0x100
#define O_TRUNC         0x200
#define O_APPEND        0x400
#define O_NONBLOCK      0x800
#define O_DIRECTORY    0x4000

/* The struct returned by the newfstatat() syscall. Differs slightly from the
 * x86_64's stat one by field ordering, so be careful.
 */
struct sys_stat_struct {
	unsigned long   st_dev;
	unsigned long   st_ino;
	unsigned int    st_mode;
	unsigned int    st_nlink;
	unsigned int    st_uid;
	unsigned int    st_gid;

	unsigned long   st_rdev;
	unsigned long   __pad1;
	long            st_size;
	int             st_blksize;
	int             __pad2;

	long            st_blocks;
	long            st_atime;
	unsigned long   st_atime_nsec;
	long            st_mtime;

	unsigned long   st_mtime_nsec;
	long            st_ctime;
	unsigned long   st_ctime_nsec;
	unsigned int    __unused[2];
};

/* Syscalls for AARCH64 :
 *   - registers are 64-bit
 *   - stack is 16-byte aligned
 *   - syscall number is passed in x8
 *   - arguments are in x0, x1, x2, x3, x4, x5
 *   - the system call is performed by calling svc 0
 *   - syscall return comes in x0.
 *   - the arguments are cast to long and assigned into the target registers
 *     which are then simply passed as registers to the asm code, so that we
 *     don't have to experience issues with register constraints.
 *
 * On aarch64, select() is not implemented so we have to use pselect6().
 */
#define __ARCH_WANT_SYS_PSELECT6

#define my_syscall0(num)                                                      \
({                                                                            \
	register long _num  __asm__ ("x8") = (num);                           \
	register long _arg1 __asm__ ("x0");                                   \
	                                                                      \
	__asm__  volatile (                                                   \
		"svc #0\n"                                                    \
		: "=r"(_arg1)                                                 \
		: "r"(_num)                                                   \
		: "memory", "cc"                                              \
	);                                                                    \
	_arg1;                                                                \
})

#define my_syscall1(num, arg1)                                                \
({                                                                            \
	register long _num  __asm__ ("x8") = (num);                           \
	register long _arg1 __asm__ ("x0") = (long)(arg1);                    \
	                                                                      \
	__asm__  volatile (                                                   \
		"svc #0\n"                                                    \
		: "=r"(_arg1)                                                 \
		: "r"(_arg1),                                                 \
		  "r"(_num)                                                   \
		: "memory", "cc"                                              \
	);                                                                    \
	_arg1;                                                                \
})

#define my_syscall2(num, arg1, arg2)                                          \
({                                                                            \
	register long _num  __asm__ ("x8") = (num);                           \
	register long _arg1 __asm__ ("x0") = (long)(arg1);                    \
	register long _arg2 __asm__ ("x1") = (long)(arg2);                    \
	                                                                      \
	__asm__  volatile (                                                   \
		"svc #0\n"                                                    \
		: "=r"(_arg1)                                                 \
		: "r"(_arg1), "r"(_arg2),                                     \
		  "r"(_num)                                                   \
		: "memory", "cc"                                              \
	);                                                                    \
	_arg1;                                                                \
})

#define my_syscall3(num, arg1, arg2, arg3)                                    \
({                                                                            \
	register long _num  __asm__ ("x8") = (num);                           \
	register long _arg1 __asm__ ("x0") = (long)(arg1);                    \
	register long _arg2 __asm__ ("x1") = (long)(arg2);                    \
	register long _arg3 __asm__ ("x2") = (long)(arg3);                    \
	                                                                      \
	__asm__  volatile (                                                   \
		"svc #0\n"                                                    \
		: "=r"(_arg1)                                                 \
		: "r"(_arg1), "r"(_arg2), "r"(_arg3),                         \
		  "r"(_num)                                                   \
		: "memory", "cc"                                              \
	);                                                                    \
	_arg1;                                                                \
})

#define my_syscall4(num, arg1, arg2, arg3, arg4)                              \
({                                                                            \
	register long _num  __asm__ ("x8") = (num);                           \
	register long _arg1 __asm__ ("x0") = (long)(arg1);                    \
	register long _arg2 __asm__ ("x1") = (long)(arg2);                    \
	register long _arg3 __asm__ ("x2") = (long)(arg3);                    \
	register long _arg4 __asm__ ("x3") = (long)(arg4);                    \
	                                                                      \
	__asm__  volatile (                                                   \
		"svc #0\n"                                                    \
		: "=r"(_arg1)                                                 \
		: "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4),             \
		  "r"(_num)                                                   \
		: "memory", "cc"                                              \
	);                                                                    \
	_arg1;                                                                \
})

#define my_syscall5(num, arg1, arg2, arg3, arg4, arg5)                        \
({                                                                            \
	register long _num  __asm__ ("x8") = (num);                           \
	register long _arg1 __asm__ ("x0") = (long)(arg1);                    \
	register long _arg2 __asm__ ("x1") = (long)(arg2);                    \
	register long _arg3 __asm__ ("x2") = (long)(arg3);                    \
	register long _arg4 __asm__ ("x3") = (long)(arg4);                    \
	register long _arg5 __asm__ ("x4") = (long)(arg5);                    \
	                                                                      \
	__asm__  volatile (                                                   \
		"svc #0\n"                                                    \
		: "=r" (_arg1)                                                \
		: "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), "r"(_arg5), \
		  "r"(_num)                                                   \
		: "memory", "cc"                                              \
	);                                                                    \
	_arg1;                                                                \
})

#define my_syscall6(num, arg1, arg2, arg3, arg4, arg5, arg6)                  \
({                                                                            \
	register long _num  __asm__ ("x8") = (num);                           \
	register long _arg1 __asm__ ("x0") = (long)(arg1);                    \
	register long _arg2 __asm__ ("x1") = (long)(arg2);                    \
	register long _arg3 __asm__ ("x2") = (long)(arg3);                    \
	register long _arg4 __asm__ ("x3") = (long)(arg4);                    \
	register long _arg5 __asm__ ("x4") = (long)(arg5);                    \
	register long _arg6 __asm__ ("x5") = (long)(arg6);                    \
	                                                                      \
	__asm__  volatile (                                                   \
		"svc #0\n"                                                    \
		: "=r" (_arg1)                                                \
		: "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), "r"(_arg5), \
		  "r"(_arg6), "r"(_num)                                       \
		: "memory", "cc"                                              \
	);                                                                    \
	_arg1;                                                                \
})

/* startup code */
__asm__ (".section .text\n"
    ".weak _start\n"
    ".global _start\n"
    "_start:\n"
    "ldr x0, [sp]\n"              // argc (x0) was in the stack
    "add x1, sp, 8\n"             // argv (x1) = sp
    "lsl x2, x0, 3\n"             // envp (x2) = 8*argc ...
    "add x2, x2, 8\n"             //           + 8 (skip null)
    "add x2, x2, x1\n"            //           + argv
    "and sp, x1, -16\n"           // sp must be 16-byte aligned in the callee
    "bl main\n"                   // main() returns the status code, we'll exit with it.
    "mov x8, 93\n"                // NR_exit == 93
    "svc #0\n"
    "");

#endif // _NOLIBC_ARCH_AARCH64_H