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
|
/* Copyright (C) 1996-2015 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Andreas Schwab (schwab@issan.informatik.uni-dortmund.de)
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library. If not, see
<http://www.gnu.org/licenses/>. */
/* clone() is even more special than fork() as it mucks with stacks
and invokes a function in the right context after its all over. */
#include <sysdep.h>
#define _ERRNO_H 1
#include <bits/errno.h>
#include <tls.h>
#define CLONE_VM 0x00000100
#define CLONE_THREAD 0x00010000
/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg,
void *parent_tidptr, void *tls, void *child_tidptr) */
.text
ENTRY (__clone)
/* Sanity check arguments. */
movel #-EINVAL, %d0
movel 4(%sp), %a0 /* no NULL function pointers */
tstl %a0
jeq SYSCALL_ERROR_LABEL
movel 8(%sp), %a1 /* no NULL stack pointers */
tstl %a1
jeq SYSCALL_ERROR_LABEL
/* Allocate space and copy the argument onto the new stack. */
movel 16(%sp), -(%a1)
/* Do the system call */
movel 12+0(%sp), %d1 /* get flags */
movel %d3, -(%a1) /* save %d3 and get parent_tidptr */
movel %d3, -(%sp)
cfi_adjust_cfa_offset (4)
cfi_rel_offset (%d3, 0)
movel 20+4(%sp), %d3
movel %d4, -(%a1) /* save %d4 and get child_tidptr */
movel %d4, -(%sp)
cfi_adjust_cfa_offset (4)
cfi_rel_offset (%d4, 0)
movel 28+8(%sp), %d4
movel %d5, -(%a1) /* save %d5 and get tls */
movel %d5, -(%sp)
cfi_adjust_cfa_offset (4)
cfi_rel_offset (%d5, 0)
movel 24+12(%sp), %d5
/* save %d2 and get stack pointer */
#ifdef __mcoldfire__
movel %d2, -(%a1)
movel %d2, -(%sp)
cfi_adjust_cfa_offset (4)
cfi_rel_offset (%d2, 0)
movel %a1, %d2
#else
exg %d2, %a1 /* save %d2 and get stack pointer */
cfi_register (%d2, %a1)
#endif
movel #SYS_ify (clone), %d0
/* End FDE now, because in the child the unwind info will be
wrong. */
cfi_endproc
trap #0
#ifdef __mcoldfire__
movel (%sp)+, %d2
#else
exg %d2, %a1 /* restore %d2 */
#endif
movel (%sp)+, %d5 /* restore %d5, %d4 and %d3 */
movel (%sp)+, %d4
movel (%sp)+, %d3
tstl %d0
jmi SYSCALL_ERROR_LABEL
jeq thread_start
rts
thread_start:
cfi_startproc
cfi_undefined (pc) /* Mark end of stack */
subl %fp, %fp /* terminate the stack frame */
/* Check and see if we need to reset the PID. */
movel %d1, %a1
andl #CLONE_THREAD, %d1
jne donepid
movel %a1, %d1
movel #-1, %d0
andl #CLONE_VM, %d1
jne gotpid
movel #SYS_ify (getpid), %d0
trap #0
gotpid:
movel %a0, -(%sp)
movel %d0, -(%sp)
bsrl __m68k_read_tp@PLTPC
movel (%sp)+, %d0
movel %d0, PID_OFFSET(%a0)
movel %d0, TID_OFFSET(%a0)
movel (%sp)+, %a0
donepid:
jsr (%a0)
movel %d0, %d1
movel #SYS_ify (exit), %d0
trap #0
cfi_endproc
cfi_startproc
PSEUDO_END (__clone)
weak_alias (__clone, clone)
|
