asm_linux_386.s raw
1 // Copyright 2009 The Go Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style
3 // license that can be found in the LICENSE file.
4
5 #include "textflag.h"
6 #include "funcdata.h"
7
8 //
9 // System calls for 386, Linux
10 //
11
12 // See ../runtime/sys_linux_386.s for the reason why we always use int 0x80
13 // instead of the glibc-specific "CALL 0x10(GS)".
14 #define INVOKE_SYSCALL INT $0x80
15
16 // func rawVforkSyscall(trap, a1, a2, a3 uintptr) (r1, err uintptr)
17 TEXT ·rawVforkSyscall(SB),NOSPLIT|NOFRAME,$0-24
18 MOVL trap+0(FP), AX // syscall entry
19 MOVL a1+4(FP), BX
20 MOVL a2+8(FP), CX
21 MOVL a3+12(FP), DX
22 POPL SI // preserve return address
23 INVOKE_SYSCALL
24 PUSHL SI
25 CMPL AX, $0xfffff001
26 JLS ok
27 MOVL $-1, r1+16(FP)
28 NEGL AX
29 MOVL AX, err+20(FP)
30 RET
31 ok:
32 MOVL AX, r1+16(FP)
33 MOVL $0, err+20(FP)
34 RET
35
36 // func rawSyscallNoError(trap uintptr, a1, a2, a3 uintptr) (r1, r2 uintptr);
37 TEXT ·rawSyscallNoError(SB),NOSPLIT,$0-24
38 MOVL trap+0(FP), AX // syscall entry
39 MOVL a1+4(FP), BX
40 MOVL a2+8(FP), CX
41 MOVL a3+12(FP), DX
42 MOVL $0, SI
43 MOVL $0, DI
44 INVOKE_SYSCALL
45 MOVL AX, r1+16(FP)
46 MOVL DX, r2+20(FP)
47 RET
48
49 #define SYS_SOCKETCALL 102 /* from zsysnum_linux_386.go */
50
51 // func socketcall(call int, a0, a1, a2, a3, a4, a5 uintptr) (n int, err int)
52 // Kernel interface gets call sub-number and pointer to a0.
53 TEXT ·socketcall(SB),NOSPLIT,$0-36
54 CALL runtime·entersyscall(SB)
55 MOVL $SYS_SOCKETCALL, AX // syscall entry
56 MOVL call+0(FP), BX // socket call number
57 LEAL a0+4(FP), CX // pointer to call arguments
58 MOVL $0, DX
59 MOVL $0, SI
60 MOVL $0, DI
61 INVOKE_SYSCALL
62 CMPL AX, $0xfffff001
63 JLS oksock
64 MOVL $-1, n+28(FP)
65 NEGL AX
66 MOVL AX, err+32(FP)
67 CALL runtime·exitsyscall(SB)
68 RET
69 oksock:
70 MOVL AX, n+28(FP)
71 MOVL $0, err+32(FP)
72 CALL runtime·exitsyscall(SB)
73 RET
74
75 // func rawsocketcall(call int, a0, a1, a2, a3, a4, a5 uintptr) (n int, err int)
76 // Kernel interface gets call sub-number and pointer to a0.
77 TEXT ·rawsocketcall(SB),NOSPLIT,$0-36
78 MOVL $SYS_SOCKETCALL, AX // syscall entry
79 MOVL call+0(FP), BX // socket call number
80 LEAL a0+4(FP), CX // pointer to call arguments
81 MOVL $0, DX
82 MOVL $0, SI
83 MOVL $0, DI
84 INVOKE_SYSCALL
85 CMPL AX, $0xfffff001
86 JLS oksock1
87 MOVL $-1, n+28(FP)
88 NEGL AX
89 MOVL AX, err+32(FP)
90 RET
91 oksock1:
92 MOVL AX, n+28(FP)
93 MOVL $0, err+32(FP)
94 RET
95
96 #define SYS__LLSEEK 140 /* from zsysnum_linux_386.go */
97 // func Seek(fd int, offset int64, whence int) (newoffset int64, err int)
98 // Implemented in assembly to avoid allocation when
99 // taking the address of the return value newoffset.
100 // Underlying system call is
101 // llseek(int fd, int offhi, int offlo, int64 *result, int whence)
102 TEXT ·seek(SB),NOSPLIT,$0-28
103 CALL runtime·entersyscall(SB)
104 MOVL $SYS__LLSEEK, AX // syscall entry
105 MOVL fd+0(FP), BX
106 MOVL offset_hi+8(FP), CX
107 MOVL offset_lo+4(FP), DX
108 LEAL newoffset_lo+16(FP), SI // result pointer
109 MOVL whence+12(FP), DI
110 INVOKE_SYSCALL
111 CMPL AX, $0xfffff001
112 JLS okseek
113 MOVL $-1, newoffset_lo+16(FP)
114 MOVL $-1, newoffset_hi+20(FP)
115 NEGL AX
116 MOVL AX, err+24(FP)
117 CALL runtime·exitsyscall(SB)
118 RET
119 okseek:
120 // system call filled in newoffset already
121 MOVL $0, err+24(FP)
122 CALL runtime·exitsyscall(SB)
123 RET
124