1 /* $NetBSD: _lwp.c,v 1.3 2003/04/07 21:04:21 kleink 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 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 #include "namespace.h" 40 #include <sys/types.h> 41 #include <ucontext.h> 42 #include <lwp.h> 43 #include <stdlib.h> 44 45 #define CALLFRAME_SIZ 24 46 47 void _lwp_makecontext(ucontext_t *u, void (*start)(void *), 48 void *arg, void *private, caddr_t stack_base, size_t stack_size) 49 { 50 caddr_t sp; 51 __greg_t *gr; 52 53 getcontext(u); 54 gr = u->uc_mcontext.__gregs; 55 u->uc_link = NULL; 56 57 u->uc_stack.ss_sp = stack_base; 58 u->uc_stack.ss_size = stack_size; 59 sp = stack_base + stack_size - CALLFRAME_SIZ; 60 61 gr[_REG_EPC] = (unsigned long) start; 62 gr[_REG_T9] = (unsigned long) start; /* required for .abicalls */ 63 gr[_REG_RA] = (unsigned long) _lwp_exit; 64 gr[_REG_A0] = (unsigned long) arg; 65 gr[_REG_SP] = (unsigned long) sp; 66 } 67