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
|
/* Copyright (C) 1997-2014 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Richard Henderson (rth@tamu.edu).
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 <asm/errno.h>
#include <asm/unistd.h>
#include <tcb-offsets.h>
#include <sysdep.h>
#define CLONE_VM 0x00000100
#define CLONE_THREAD 0x00010000
/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg,
pid_t *ptid, void *tls, pid_t *ctid); */
.register %g2,#scratch
.register %g3,#scratch
.text
ENTRY (__clone)
save %sp, -192, %sp
cfi_def_cfa_register(%fp)
cfi_window_save
cfi_register(%o7, %i7)
/* sanity check arguments */
brz,pn %i0, 99f /* fn non-NULL? */
mov %i0, %g2
brz,pn %i1, 99f /* child_stack non-NULL? */
mov %i2, %o0 /* clone flags */
/* The child_stack is the top of the stack, allocate one
whole stack frame from that as this is what the kernel
expects. Also, subtract STACK_BIAS. */
sub %i1, 192 + 0x7ff, %o1
mov %i3, %g3
mov %i2, %g4
mov %i4,%o2 /* PTID */
mov %i5,%o3 /* TLS */
ldx [%fp+0x7ff+176],%o4 /* CTID */
/* Do the system call */
set __NR_clone, %g1
ta 0x6d
bcs,pn %xcc, 98f
nop
brnz,pn %o1, __thread_start
nop
jmpl %i7 + 8, %g0
restore %o0, %g0, %o0
99: mov EINVAL, %o0
98: call HIDDEN_JUMPTARGET(__errno_location)
mov %o0, %i0
st %i0, [%o0]
jmpl %i7 + 8, %g0
restore %g0,-1,%o0
END(__clone)
.type __thread_start,@function
__thread_start:
sethi %hi(CLONE_THREAD), %l0
andcc %g4, %l0, %g0
bne,pt %icc, 1f
andcc %g4, CLONE_VM, %g0
bne,a,pn %icc, 2f
mov -1,%o0
set __NR_getpid,%g1
ta 0x6d
2: st %o0,[%g7 + PID]
st %o0,[%g7 + TID]
1:
mov %g0, %fp /* terminate backtrace */
call %g2
mov %g3,%o0
call HIDDEN_JUMPTARGET(_exit),0
nop
.size __thread_start, .-__thread_start
weak_alias (__clone, clone)
|
GitWeb