1 /* $NetBSD: _lwp.c,v 1.7 2025/04/25 01:18:38 riastradh Exp $ */
2
3 /*
4 * Copyright (c) 2001 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Wayne Knowles
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 #if defined(LIBC_SCCS) && !defined(lint)
34 __RCSID("$NetBSD: _lwp.c,v 1.7 2025/04/25 01:18:38 riastradh Exp $");
35 #endif /* LIBC_SCCS and not lint */
36
37 #include "namespace.h"
38
39 #include <sys/param.h>
40 #include <sys/types.h>
41
42 #include <machine/frame.h>
43
44 #include <lwp.h>
45 #include <stdlib.h>
46 #include <ucontext.h>
47
48 void
_lwp_makecontext(ucontext_t * u,void (* start)(void *),void * arg,void * private,caddr_t stack_base,size_t stack_size)49 _lwp_makecontext(ucontext_t *u, void (*start)(void *),
50 void *arg, void *private, caddr_t stack_base, size_t stack_size)
51 {
52 caddr_t sp;
53 __greg_t *gr;
54 __greg_t *gp;
55 __greg_t fp;
56
57 getcontext(u);
58 gr = u->uc_mcontext.__gregs;
59 u->uc_link = NULL;
60
61 u->uc_stack.ss_sp = stack_base;
62 u->uc_stack.ss_size = stack_size;
63 sp = stack_base + HPPA_FRAME_SIZE;
64 sp = (caddr_t)(((uintptr_t)sp + STACK_ALIGNBYTES) & ~STACK_ALIGNBYTES);
65
66 fp = (__greg_t)start;
67 if (fp & 2) {
68 gp = (__greg_t *)(fp & ~3);
69 fp = gp[0];
70 gr[_REG_R19] = gp[1];
71 }
72 gr[_REG_PCOQH] = fp | HPPA_PC_PRIV_USER;
73 gr[_REG_PCOQT] = (fp + 4) | HPPA_PC_PRIV_USER;
74 gr[_REG_RP] = (__greg_t) _lwp_exit;
75 gr[_REG_ARG0] = (__greg_t) arg;
76 gr[_REG_SP] = (__greg_t) sp;
77 gr[_REG_CR27] = (__greg_t) private;
78 }
79