1 /* Copyright (C) 1996-2015 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Andreas Schwab (schwab@issan.informatik.uni-dortmund.de)
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library. If not, see
17 <http://www.gnu.org/licenses/>. */
19 /* clone() is even more special than fork() as it mucks with stacks
20 and invokes a function in the right context after its all over. */
24 #include <bits/errno.h>
27 #define CLONE_VM 0x00000100
28 #define CLONE_THREAD 0x00010000
30 /* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg,
31 void *parent_tidptr, void *tls, void *child_tidptr) */
36 /* Sanity check arguments. */
38 movel 4(%sp), %a0 /* no NULL function pointers */
40 jeq SYSCALL_ERROR_LABEL
41 movel 8(%sp), %a1 /* no NULL stack pointers */
43 jeq SYSCALL_ERROR_LABEL
45 /* Allocate space and copy the argument onto the new stack. */
48 /* Do the system call */
49 movel 12+0(%sp), %d1 /* get flags */
50 movel %d3, -(%a1) /* save %d3 and get parent_tidptr */
52 cfi_adjust_cfa_offset (4)
53 cfi_rel_offset (%d3, 0)
55 movel %d4, -(%a1) /* save %d4 and get child_tidptr */
57 cfi_adjust_cfa_offset (4)
58 cfi_rel_offset (%d4, 0)
60 movel %d5, -(%a1) /* save %d5 and get tls */
62 cfi_adjust_cfa_offset (4)
63 cfi_rel_offset (%d5, 0)
65 /* save %d2 and get stack pointer */
69 cfi_adjust_cfa_offset (4)
70 cfi_rel_offset (%d2, 0)
73 exg %d2, %a1 /* save %d2 and get stack pointer */
74 cfi_register (%d2, %a1)
76 movel #SYS_ify (clone), %d0
78 /* End FDE now, because in the child the unwind info will be
86 exg %d2, %a1 /* restore %d2 */
88 movel (%sp)+, %d5 /* restore %d5, %d4 and %d3 */
93 jmi SYSCALL_ERROR_LABEL
100 cfi_undefined (pc) /* Mark end of stack */
101 subl %fp, %fp /* terminate the stack frame */
102 /* Check and see if we need to reset the PID. */
104 andl #CLONE_THREAD, %d1
110 movel #SYS_ify (getpid), %d0
115 bsrl __m68k_read_tp@PLTPC
117 movel %d0, PID_OFFSET(%a0)
118 movel %d0, TID_OFFSET(%a0)
123 movel #SYS_ify (exit), %d0
130 weak_alias (__clone, clone)