1 /* $NetBSD: _lwp.c,v 1.7 2012/03/17 20:48:58 martin Exp $ */
2
3 /*-
4 * Copyright (c) 2002 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 #if defined(LIBC_SCCS) && !defined(lint)
31 __RCSID("$NetBSD: _lwp.c,v 1.7 2012/03/17 20:48:58 martin Exp $");
32 #endif /* LIBC_SCCS and not lint */
33
34 #include "namespace.h"
35 #include <sys/types.h>
36 #include <ucontext.h>
37 #include <lwp.h>
38 #include <stdlib.h>
39
40 void
_lwp_makecontext(ucontext_t * u,void (* start)(void *),void * arg,void * private,caddr_t stack_base,size_t stack_size)41 _lwp_makecontext(ucontext_t *u, void (*start)(void *),
42 void *arg, void *private,
43 caddr_t stack_base, size_t stack_size)
44 {
45 __greg_t *gr;
46 unsigned long *sp;
47
48 getcontext(u);
49 gr = u->uc_mcontext.__gregs;
50
51 u->uc_link = NULL;
52
53 u->uc_stack.ss_sp = stack_base;
54 u->uc_stack.ss_size = stack_size;
55
56 /*LINTED*/
57 sp = (ulong *)(stack_base + stack_size);
58 sp = (ulong *)((ulong)sp & ~0x0f);
59
60 sp -= 8 + 8 + 6;
61
62 sp[8] = (ulong)arg;
63 sp[14] = (ulong)sp - 2047;
64 sp[15] = (ulong)_lwp_exit - 8;
65
66 /*LINTED*/
67 sp = (ulong *)((caddr_t)sp - 2047);
68
69 gr[_REG_PC] = (ulong) start;
70 gr[_REG_nPC] = (ulong) start + 4;
71
72 gr[_REG_O0] = (ulong) arg;
73 gr[_REG_O6] = (ulong) sp;
74 gr[_REG_O7] = (ulong)_lwp_exit - 8;
75 gr[_REG_G7] = (ulong)private;
76 }
77