1 | /* Copyright (C) 1996-2022 Free Software Foundation, Inc. |
2 | This file is part of the GNU C Library. |
3 | |
4 | The GNU C Library is free software; you can redistribute it and/or |
5 | modify it under the terms of the GNU Lesser General Public |
6 | License as published by the Free Software Foundation; either |
7 | version 2.1 of the License, or (at your option) any later version. |
8 | |
9 | The GNU C Library is distributed in the hope that it will be useful, |
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
12 | Lesser General Public License for more details. |
13 | |
14 | You should have received a copy of the GNU Lesser General Public |
15 | License along with the GNU C Library. If not, see |
16 | <https://www.gnu.org/licenses/>. */ |
17 | |
18 | /* clone() is even more special than fork() as it mucks with stacks |
19 | and invokes a function in the right context after its all over. */ |
20 | |
21 | #include <sysdep.h> |
22 | #define _ERRNO_H 1 |
23 | #include <bits/errno.h> |
24 | #include <tls.h> |
25 | |
26 | /* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg, |
27 | void *parent_tidptr, void *tls, void *child_tidptr) */ |
28 | |
29 | .text |
30 | ENTRY (__clone) |
31 | |
32 | /* Sanity check arguments. */ |
33 | movel #-EINVAL, %d0 |
34 | movel 4(%sp), %a0 /* no NULL function pointers */ |
35 | tstl %a0 |
36 | jeq SYSCALL_ERROR_LABEL |
37 | movel 8(%sp), %a1 /* no NULL stack pointers */ |
38 | tstl %a1 |
39 | jeq SYSCALL_ERROR_LABEL |
40 | |
41 | /* Allocate space and copy the argument onto the new stack. */ |
42 | movel 16(%sp), -(%a1) |
43 | |
44 | /* Do the system call */ |
45 | movel 12+0(%sp), %d1 /* get flags */ |
46 | movel %d3, -(%a1) /* save %d3 and get parent_tidptr */ |
47 | movel %d3, -(%sp) |
48 | cfi_adjust_cfa_offset (4) |
49 | cfi_rel_offset (%d3, 0) |
50 | movel 20+4(%sp), %d3 |
51 | movel %d4, -(%a1) /* save %d4 and get child_tidptr */ |
52 | movel %d4, -(%sp) |
53 | cfi_adjust_cfa_offset (4) |
54 | cfi_rel_offset (%d4, 0) |
55 | movel 28+8(%sp), %d4 |
56 | movel %d5, -(%a1) /* save %d5 and get tls */ |
57 | movel %d5, -(%sp) |
58 | cfi_adjust_cfa_offset (4) |
59 | cfi_rel_offset (%d5, 0) |
60 | movel 24+12(%sp), %d5 |
61 | /* save %d2 and get stack pointer */ |
62 | #ifdef __mcoldfire__ |
63 | movel %d2, -(%a1) |
64 | movel %d2, -(%sp) |
65 | cfi_adjust_cfa_offset (4) |
66 | cfi_rel_offset (%d2, 0) |
67 | movel %a1, %d2 |
68 | #else |
69 | exg %d2, %a1 /* save %d2 and get stack pointer */ |
70 | cfi_register (%d2, %a1) |
71 | #endif |
72 | movel #SYS_ify (clone), %d0 |
73 | |
74 | /* End FDE now, because in the child the unwind info will be |
75 | wrong. */ |
76 | cfi_endproc |
77 | |
78 | trap #0 |
79 | #ifdef __mcoldfire__ |
80 | movel (%sp)+, %d2 |
81 | #else |
82 | exg %d2, %a1 /* restore %d2 */ |
83 | #endif |
84 | movel (%sp)+, %d5 /* restore %d5, %d4 and %d3 */ |
85 | movel (%sp)+, %d4 |
86 | movel (%sp)+, %d3 |
87 | |
88 | tstl %d0 |
89 | jmi SYSCALL_ERROR_LABEL |
90 | jeq 1f |
91 | |
92 | rts |
93 | |
94 | 1: |
95 | cfi_startproc |
96 | cfi_undefined (pc) /* Mark end of stack */ |
97 | subl %fp, %fp /* terminate the stack frame */ |
98 | jsr (%a0) |
99 | movel %d0, %d1 |
100 | movel #SYS_ify (exit), %d0 |
101 | trap #0 |
102 | cfi_endproc |
103 | |
104 | cfi_startproc |
105 | PSEUDO_END (__clone) |
106 | |
107 | libc_hidden_def (__clone) |
108 | weak_alias (__clone, clone) |
109 | |