1*0Sstevel@tonic-gate /* 2*0Sstevel@tonic-gate * CDDL HEADER START 3*0Sstevel@tonic-gate * 4*0Sstevel@tonic-gate * The contents of this file are subject to the terms of the 5*0Sstevel@tonic-gate * Common Development and Distribution License, Version 1.0 only 6*0Sstevel@tonic-gate * (the "License"). You may not use this file except in compliance 7*0Sstevel@tonic-gate * with the License. 8*0Sstevel@tonic-gate * 9*0Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10*0Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing. 11*0Sstevel@tonic-gate * See the License for the specific language governing permissions 12*0Sstevel@tonic-gate * and limitations under the License. 13*0Sstevel@tonic-gate * 14*0Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each 15*0Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16*0Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the 17*0Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying 18*0Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner] 19*0Sstevel@tonic-gate * 20*0Sstevel@tonic-gate * CDDL HEADER END 21*0Sstevel@tonic-gate */ 22*0Sstevel@tonic-gate /* 23*0Sstevel@tonic-gate * Copyright 2004 Sun Microsystems, Inc. All rights reserved. 24*0Sstevel@tonic-gate * Use is subject to license terms. 25*0Sstevel@tonic-gate */ 26*0Sstevel@tonic-gate 27*0Sstevel@tonic-gate /* Copyright (c) 1988 AT&T */ 28*0Sstevel@tonic-gate /* All Rights Reserved */ 29*0Sstevel@tonic-gate 30*0Sstevel@tonic-gate 31*0Sstevel@tonic-gate #pragma ident "%Z%%M% %I% %E% SMI" 32*0Sstevel@tonic-gate 33*0Sstevel@tonic-gate #pragma weak makecontext = _makecontext 34*0Sstevel@tonic-gate 35*0Sstevel@tonic-gate #include "synonyms.h" 36*0Sstevel@tonic-gate #include <stdarg.h> 37*0Sstevel@tonic-gate #include <ucontext.h> 38*0Sstevel@tonic-gate #include <sys/stack.h> 39*0Sstevel@tonic-gate 40*0Sstevel@tonic-gate /* 41*0Sstevel@tonic-gate * The ucontext_t that the user passes in must have been primed with a 42*0Sstevel@tonic-gate * call to getcontext(2), have the uc_stack member set to reflect the 43*0Sstevel@tonic-gate * stack which this context will use, and have the uc_link member set 44*0Sstevel@tonic-gate * to the context which should be resumed when this context returns. 45*0Sstevel@tonic-gate * When makecontext() returns, the ucontext_t will be set to run the 46*0Sstevel@tonic-gate * given function with the given parameters on the stack specified by 47*0Sstevel@tonic-gate * uc_stack, and which will return to the ucontext_t specified by uc_link. 48*0Sstevel@tonic-gate */ 49*0Sstevel@tonic-gate 50*0Sstevel@tonic-gate static void resumecontext(void); 51*0Sstevel@tonic-gate 52*0Sstevel@tonic-gate void 53*0Sstevel@tonic-gate makecontext(ucontext_t *ucp, void (*func)(), int argc, ...) 54*0Sstevel@tonic-gate { 55*0Sstevel@tonic-gate long *sp; 56*0Sstevel@tonic-gate long *tsp; 57*0Sstevel@tonic-gate va_list ap; 58*0Sstevel@tonic-gate size_t size; 59*0Sstevel@tonic-gate int pusharg = (argc > 6 ? argc - 6 : 0); 60*0Sstevel@tonic-gate greg_t tmp; 61*0Sstevel@tonic-gate int i; 62*0Sstevel@tonic-gate 63*0Sstevel@tonic-gate ucp->uc_mcontext.gregs[REG_PC] = (greg_t)func; 64*0Sstevel@tonic-gate 65*0Sstevel@tonic-gate size = sizeof (long) * (pusharg + 1); 66*0Sstevel@tonic-gate 67*0Sstevel@tonic-gate /* 68*0Sstevel@tonic-gate * Calculate new value for %rsp. On entry to a function, 69*0Sstevel@tonic-gate * %rsp must be STACK_ENTRY_ALIGNed but not STACK_ALIGNed. 70*0Sstevel@tonic-gate * This is because the pushq %rbp will correct the alignment. 71*0Sstevel@tonic-gate */ 72*0Sstevel@tonic-gate 73*0Sstevel@tonic-gate sp = (long *)(((uintptr_t)ucp->uc_stack.ss_sp + 74*0Sstevel@tonic-gate ucp->uc_stack.ss_size - size) & ~(STACK_ENTRY_ALIGN - 1)); 75*0Sstevel@tonic-gate 76*0Sstevel@tonic-gate if (((uintptr_t)sp & (STACK_ALIGN - 1ul)) == 0) 77*0Sstevel@tonic-gate sp -= STACK_ENTRY_ALIGN / sizeof (*sp); 78*0Sstevel@tonic-gate 79*0Sstevel@tonic-gate tsp = sp + 1; 80*0Sstevel@tonic-gate 81*0Sstevel@tonic-gate va_start(ap, argc); 82*0Sstevel@tonic-gate 83*0Sstevel@tonic-gate for (i = 0; i < argc; i++) { 84*0Sstevel@tonic-gate tmp = va_arg(ap, long); 85*0Sstevel@tonic-gate switch (i) { 86*0Sstevel@tonic-gate case 0: 87*0Sstevel@tonic-gate ucp->uc_mcontext.gregs[REG_RDI] = tmp; 88*0Sstevel@tonic-gate break; 89*0Sstevel@tonic-gate case 1: 90*0Sstevel@tonic-gate ucp->uc_mcontext.gregs[REG_RSI] = tmp; 91*0Sstevel@tonic-gate break; 92*0Sstevel@tonic-gate case 2: 93*0Sstevel@tonic-gate ucp->uc_mcontext.gregs[REG_RDX] = tmp; 94*0Sstevel@tonic-gate break; 95*0Sstevel@tonic-gate case 3: 96*0Sstevel@tonic-gate ucp->uc_mcontext.gregs[REG_RCX] = tmp; 97*0Sstevel@tonic-gate break; 98*0Sstevel@tonic-gate case 4: 99*0Sstevel@tonic-gate ucp->uc_mcontext.gregs[REG_R8] = tmp; 100*0Sstevel@tonic-gate break; 101*0Sstevel@tonic-gate case 5: 102*0Sstevel@tonic-gate ucp->uc_mcontext.gregs[REG_R9] = tmp; 103*0Sstevel@tonic-gate break; 104*0Sstevel@tonic-gate default: 105*0Sstevel@tonic-gate *tsp++ = tmp; 106*0Sstevel@tonic-gate break; 107*0Sstevel@tonic-gate } 108*0Sstevel@tonic-gate } 109*0Sstevel@tonic-gate 110*0Sstevel@tonic-gate va_end(ap); 111*0Sstevel@tonic-gate 112*0Sstevel@tonic-gate *sp = (long)resumecontext; /* return address */ 113*0Sstevel@tonic-gate 114*0Sstevel@tonic-gate ucp->uc_mcontext.gregs[REG_SP] = (greg_t)sp; 115*0Sstevel@tonic-gate } 116*0Sstevel@tonic-gate 117*0Sstevel@tonic-gate 118*0Sstevel@tonic-gate static void 119*0Sstevel@tonic-gate resumecontext(void) 120*0Sstevel@tonic-gate { 121*0Sstevel@tonic-gate ucontext_t uc; 122*0Sstevel@tonic-gate 123*0Sstevel@tonic-gate getcontext(&uc); 124*0Sstevel@tonic-gate setcontext(uc.uc_link); 125*0Sstevel@tonic-gate } 126