summaryrefslogtreecommitdiff
path: root/src/pkg/syscall/asm_linux_386.s
blob: cf2ab02abe5efa6d985c3f8762f56abcc3be8d89 (plain)
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
// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

#include "../../cmd/ld/textflag.h"

//
// System calls for 386, Linux
//

// func Syscall(trap uintptr, a1, a2, a3 uintptr) (r1, r2, err uintptr);
// Trap # in AX, args in BX CX DX SI DI, return in AX

TEXT	·Syscall(SB),NOSPLIT,$0-32
	CALL	runtime·entersyscall(SB)
	MOVL	4(SP), AX	// syscall entry
	MOVL	8(SP), BX
	MOVL	12(SP), CX
	MOVL	16(SP), DX
	MOVL	$0, SI
	MOVL	$0,  DI
	CALL	*runtime·_vdso(SB)
	CMPL	AX, $0xfffff001
	JLS	ok
	MOVL	$-1, 20(SP)	// r1
	MOVL	$0, 24(SP)	// r2
	NEGL	AX
	MOVL	AX, 28(SP)  // errno
	CALL	runtime·exitsyscall(SB)
	RET
ok:
	MOVL	AX, 20(SP)	// r1
	MOVL	DX, 24(SP)	// r2
	MOVL	$0, 28(SP)	// errno
	CALL	runtime·exitsyscall(SB)
	RET

// func Syscall6(trap uintptr, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr);
TEXT	·Syscall6(SB),NOSPLIT,$0-44
	CALL	runtime·entersyscall(SB)
	MOVL	4(SP), AX	// syscall entry
	MOVL	8(SP), BX
	MOVL	12(SP), CX
	MOVL	16(SP), DX
	MOVL	20(SP), SI
	MOVL	24(SP), DI
	MOVL	28(SP), BP
	CALL	*runtime·_vdso(SB)
	CMPL	AX, $0xfffff001
	JLS	ok6
	MOVL	$-1, 32(SP)	// r1
	MOVL	$0, 36(SP)	// r2
	NEGL	AX
	MOVL	AX, 40(SP)  // errno
	CALL	runtime·exitsyscall(SB)
	RET
ok6:
	MOVL	AX, 32(SP)	// r1
	MOVL	DX, 36(SP)	// r2
	MOVL	$0, 40(SP)	// errno
	CALL	runtime·exitsyscall(SB)
	RET

// func RawSyscall(trap uintptr, a1, a2, a3 uintptr) (r1, r2, err uintptr);
TEXT ·RawSyscall(SB),NOSPLIT,$0-32
	MOVL	4(SP), AX	// syscall entry
	MOVL	8(SP), BX
	MOVL	12(SP), CX
	MOVL	16(SP), DX
	MOVL	$0, SI
	MOVL	$0,  DI
	CALL	*runtime·_vdso(SB)
	CMPL	AX, $0xfffff001
	JLS	ok1
	MOVL	$-1, 20(SP)	// r1
	MOVL	$0, 24(SP)	// r2
	NEGL	AX
	MOVL	AX, 28(SP)  // errno
	RET
ok1:
	MOVL	AX, 20(SP)	// r1
	MOVL	DX, 24(SP)	// r2
	MOVL	$0, 28(SP)	// errno
	RET

// func RawSyscall6(trap uintptr, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr);
TEXT	·RawSyscall6(SB),NOSPLIT,$0-44
	MOVL	4(SP), AX	// syscall entry
	MOVL	8(SP), BX
	MOVL	12(SP), CX
	MOVL	16(SP), DX
	MOVL	20(SP), SI
	MOVL	24(SP), DI
	MOVL	28(SP), BP
	CALL	*runtime·_vdso(SB)
	CMPL	AX, $0xfffff001
	JLS	ok2
	MOVL	$-1, 32(SP)	// r1
	MOVL	$0, 36(SP)	// r2
	NEGL	AX
	MOVL	AX, 40(SP)  // errno
	RET
ok2:
	MOVL	AX, 32(SP)	// r1
	MOVL	DX, 36(SP)	// r2
	MOVL	$0, 40(SP)	// errno
	RET

#define SYS_SOCKETCALL 102	/* from zsysnum_linux_386.go */

// func socketcall(call int, a0, a1, a2, a3, a4, a5 uintptr) (n int, errno int)
// Kernel interface gets call sub-number and pointer to a0.
TEXT ·socketcall(SB),NOSPLIT,$0-40
	CALL	runtime·entersyscall(SB)
	MOVL	$SYS_SOCKETCALL, AX	// syscall entry
	MOVL	4(SP), BX	// socket call number
	LEAL		8(SP), CX	// pointer to call arguments
	MOVL	$0, DX
	MOVL	$0, SI
	MOVL	$0,  DI
	CALL	*runtime·_vdso(SB)
	CMPL	AX, $0xfffff001
	JLS	oksock
	MOVL	$-1, 32(SP)	// n
	NEGL	AX
	MOVL	AX, 36(SP)  // errno
	CALL	runtime·exitsyscall(SB)
	RET
oksock:
	MOVL	AX, 32(SP)	// n
	MOVL	$0, 36(SP)	// errno
	CALL	runtime·exitsyscall(SB)
	RET

// func rawsocketcall(call int, a0, a1, a2, a3, a4, a5 uintptr) (n int, errno int)
// Kernel interface gets call sub-number and pointer to a0.
TEXT ·rawsocketcall(SB),NOSPLIT,$0-40
	MOVL	$SYS_SOCKETCALL, AX	// syscall entry
	MOVL	4(SP), BX	// socket call number
	LEAL		8(SP), CX	// pointer to call arguments
	MOVL	$0, DX
	MOVL	$0, SI
	MOVL	$0,  DI
	CALL	*runtime·_vdso(SB)
	CMPL	AX, $0xfffff001
	JLS	oksock1
	MOVL	$-1, 32(SP)	// n
	NEGL	AX
	MOVL	AX, 36(SP)  // errno
	RET
oksock1:
	MOVL	AX, 32(SP)	// n
	MOVL	$0, 36(SP)	// errno
	RET

#define SYS__LLSEEK 140	/* from zsysnum_linux_386.go */
// func Seek(fd int, offset int64, whence int) (newoffset int64, errno int)
// Implemented in assembly to avoid allocation when
// taking the address of the return value newoffset.
// Underlying system call is
//	llseek(int fd, int offhi, int offlo, int64 *result, int whence)
TEXT ·Seek(SB),NOSPLIT,$0-32
	CALL	runtime·entersyscall(SB)
	MOVL	$SYS__LLSEEK, AX	// syscall entry
	MOVL	4(SP), BX	// fd
	MOVL	12(SP), CX	// offset-high
	MOVL	8(SP), DX	// offset-low
	LEAL	20(SP), SI	// result pointer
	MOVL	16(SP),  DI	// whence
	CALL	*runtime·_vdso(SB)
	CMPL	AX, $0xfffff001
	JLS	okseek
	MOVL	$-1, 20(SP)	// newoffset low
	MOVL	$-1, 24(SP)	// newoffset high
	NEGL	AX
	MOVL	AX, 28(SP)  // errno
	CALL	runtime·exitsyscall(SB)
	RET
okseek:
	// system call filled in newoffset already
	MOVL	$0, 28(SP)	// errno
	CALL	runtime·exitsyscall(SB)
	RET