1/* $NetBSD: _lwp.c,v 1.5 2008/04/28 20:22:57 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 1.5 2008/04/28 20:22:57 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 40void 41_lwp_makecontext(ucontext_t *u, void (*start)(void *), void *arg, 42 void *private, caddr_t stack_base, size_t stack_size) 43{ 44 __greg_t *gr; 45 unsigned long *sp; 46 47 getcontext(u); 48 gr = u->uc_mcontext.__gregs; 49 50 u->uc_link = NULL; 51 52 u->uc_stack.ss_sp = stack_base; 53 u->uc_stack.ss_size = stack_size; 54 55 56 sp = (ulong *)(stack_base + stack_size); 57 sp = (ulong *)((ulong)sp & ~0x07); 58 59 /* Make room for the fake caller stack frame (CCFSZ, only in words) */ 60 sp -= 8 + 8 + 1 + 6 + 1; 61 62 /* Entering (*start)(arg), return is to _lwp_exit */ 63 gr[_REG_PC] = (ulong) start; 64 gr[_REG_nPC] = (ulong) start + 4; 65 gr[_REG_O0] = (ulong)arg; 66 gr[_REG_O6] = (ulong)sp; 67 gr[_REG_O7] = (ulong)_lwp_exit - 8; 68 gr[_REG_G7] = (ulong)private; 69 70 /* XXX: uwe: why do we need this? */ 71 /* create loopback in the window save area on the stack? */ 72 sp[8+6] = (ulong)sp; /* %i6 */ 73 sp[8+7] = (ulong)_lwp_exit - 8; /* %i7 */ 74} 75