1 /* $NetBSD: _lwp.c,v 1.6 2009/07/02 09:57:09 joerg 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 Nathan J. Williams. 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 1.6 2009/07/02 09:57:09 joerg Exp $"); 35 #endif /* LIBC_SCCS and not lint */ 36 37 #include "namespace.h" 38 #include <sys/types.h> 39 #include <inttypes.h> 40 #include <ucontext.h> 41 #include <lwp.h> 42 #include <stdlib.h> 43 44 void 45 _lwp_makecontext(ucontext_t *u, void (*start)(void *), 46 void *arg, void *private, caddr_t stack_base, size_t stack_size) 47 { 48 __greg_t *gr = u->uc_mcontext.__gregs; 49 void **sp; 50 51 getcontext(u); 52 u->uc_link = NULL; 53 54 u->uc_stack.ss_sp = stack_base; 55 u->uc_stack.ss_size = stack_size; 56 57 /* LINTED uintptr_t is safe */ 58 gr[_REG_RIP] = (uintptr_t)start; 59 60 sp = (void **) (((uintptr_t)(stack_base + stack_size) & ~15)); 61 62 /* LINTED __greg_t is safe */ 63 gr[_REG_RDI] = (__greg_t)arg; 64 *--sp = (void *) _lwp_exit; 65 66 /* LINTED uintptr_t is safe */ 67 gr[_REG_URSP] = (uintptr_t) sp; 68 69 /* LINTED private is currently unused */ 70 } 71