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 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