1/* $NetBSD: _resumecontext.S,v 1.7 2012/09/12 02:00:52 manu 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 <machine/asm.h> 33 34#include "SYS.h" 35#include "assym.h" 36 37#if defined(SYSLIBC_SCCS) && !defined(lint) 38 RCSID("$NetBSD: _resumecontext.S,v 1.7 2012/09/12 02:00:52 manu Exp $") 39#endif /* SYSLIBC_SCCS && !lint */ 40 41 .set reorder 42 .hidden _C_LABEL(__resumecontext) 43 44LEAF_NOPROFILE(__resumecontext) 45 /* 46 * We get here not by a call through $t9 but thru $ra after the 47 * function passed to makecontext returns. 48 */ 49 PTR_SUBU sp, sp, UCONTEXT_SIZE # get space for ucontext 50 move a0, sp # arg0 for getcontext 51 PTR_S zero, _OFFSETOF_UC_LINK(a0) # make sure uc_link is 0 52 SYSTRAP(getcontext) # get context 53 PTR_L a0, _OFFSETOF_UC_LINK(a0) # linked context? 54 beq a0, zero, 1f # nope, exit process 55 nop 56 PIC_TAILCALL(setcontext) # yes, become it. 57 /* NOTREACHED (in theory) */ 58 li a0, -1 # failure, 591: 60 SYSTRAP(exit) # all hope is lost. 61 /* NOTREACHED */ 62END(__resumecontext) 63