1*3235Sraf/* 2*3235Sraf * CDDL HEADER START 3*3235Sraf * 4*3235Sraf * The contents of this file are subject to the terms of the 5*3235Sraf * Common Development and Distribution License (the "License"). 6*3235Sraf * You may not use this file except in compliance with the License. 7*3235Sraf * 8*3235Sraf * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9*3235Sraf * or http://www.opensolaris.org/os/licensing. 10*3235Sraf * See the License for the specific language governing permissions 11*3235Sraf * and limitations under the License. 12*3235Sraf * 13*3235Sraf * When distributing Covered Code, include this CDDL HEADER in each 14*3235Sraf * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15*3235Sraf * If applicable, add the following below this CDDL HEADER, with the 16*3235Sraf * fields enclosed by brackets "[]" replaced with your own identifying 17*3235Sraf * information: Portions Copyright [yyyy] [name of copyright owner] 18*3235Sraf * 19*3235Sraf * CDDL HEADER END 20*3235Sraf */ 21*3235Sraf 22*3235Sraf/* Copyright (c) 1988 AT&T */ 23*3235Sraf/* All Rights Reserved */ 24*3235Sraf 25*3235Sraf/* 26*3235Sraf * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 27*3235Sraf * Use is subject to license terms. 28*3235Sraf */ 29*3235Sraf 30*3235Sraf#pragma ident "%Z%%M% %I% %E% SMI" 31*3235Sraf 32*3235Sraf .file "%M%" 33*3235Sraf 34*3235Sraf#include <sys/asm_linkage.h> 35*3235Sraf 36*3235Sraf ANSI_PRAGMA_WEAK(vforkx,function) 37*3235Sraf ANSI_PRAGMA_WEAK(vfork,function) 38*3235Sraf 39*3235Sraf#include "SYS.h" 40*3235Sraf#include <assym.h> 41*3235Sraf 42*3235Sraf/* 43*3235Sraf * pid = vforkx(flags); 44*3235Sraf * syscall trap: forksys(2, flags) 45*3235Sraf * 46*3235Sraf * pid = vfork(); 47*3235Sraf * syscall trap: forksys(2, 0) 48*3235Sraf * 49*3235Sraf * From the syscall: 50*3235Sraf * %o1 == 0 in parent process, %o1 == 1 in child process. 51*3235Sraf * %o0 == pid of child in parent, %o0 == pid of parent in child. 52*3235Sraf * 53*3235Sraf * The child gets a zero return value. 54*3235Sraf * The parent gets the pid of the child. 55*3235Sraf */ 56*3235Sraf 57*3235Sraf/* 58*3235Sraf * Note that since the SPARC architecture maintains stack maintence 59*3235Sraf * information (return pc, sp, fp) in the register windows, both parent 60*3235Sraf * and child can execute in a common address space without conflict. 61*3235Sraf * 62*3235Sraf * We block all blockable signals while performing the vfork() system call 63*3235Sraf * trap. This enables us to set curthread->ul_vfork safely, so that we 64*3235Sraf * don't end up in a signal handler with curthread->ul_vfork set wrong. 65*3235Sraf */ 66*3235Sraf 67*3235Sraf ENTRY_NP(vforkx) 68*3235Sraf ba 0f 69*3235Sraf mov %o0, %o3 /* flags */ 70*3235Sraf ENTRY_NP(vfork) 71*3235Sraf clr %o3 /* flags = 0 */ 72*3235Sraf0: 73*3235Sraf mov SIG_SETMASK, %o0 /* block all signals */ 74*3235Sraf set MASKSET0, %o1 75*3235Sraf set MASKSET1, %o2 76*3235Sraf SYSTRAP_2RVALS(lwp_sigmask) 77*3235Sraf 78*3235Sraf mov %o3, %o1 /* flags */ 79*3235Sraf mov 2, %o0 80*3235Sraf SYSTRAP_2RVALS(forksys) /* vforkx(flags) */ 81*3235Sraf bcc,a,pt %icc, 1f 82*3235Sraf tst %o1 83*3235Sraf 84*3235Sraf mov %o0, %o3 /* save the vfork() error number */ 85*3235Sraf 86*3235Sraf mov SIG_SETMASK, %o0 /* reinstate signals */ 87*3235Sraf ld [%g7 + UL_SIGMASK], %o1 88*3235Sraf ld [%g7 + UL_SIGMASK + 4], %o2 89*3235Sraf SYSTRAP_2RVALS(lwp_sigmask) 90*3235Sraf 91*3235Sraf ba __cerror 92*3235Sraf mov %o3, %o0 /* restore the vfork() error number */ 93*3235Sraf 94*3235Sraf1: 95*3235Sraf /* 96*3235Sraf * To determine if we are (still) a child of vfork(), the child 97*3235Sraf * increments curthread->ul_vfork by one and the parent decrements 98*3235Sraf * it by one. If the result is zero, then we are not a child of 99*3235Sraf * vfork(), else we are. We do this to deal with the case of 100*3235Sraf * a vfork() child calling vfork(). 101*3235Sraf */ 102*3235Sraf bnz,pt %icc, 2f 103*3235Sraf ld [%g7 + UL_VFORK], %g1 104*3235Sraf brnz,a,pt %g1, 3f /* don't let it go negative */ 105*3235Sraf sub %g1, 1, %g1 /* curthread->ul_vfork--; */ 106*3235Sraf ba,a 3f 107*3235Sraf2: 108*3235Sraf clr %o0 /* zero the return value in the child */ 109*3235Sraf add %g1, 1, %g1 /* curthread->ul_vfork++; */ 110*3235Sraf3: 111*3235Sraf st %g1, [%g7 + UL_VFORK] 112*3235Sraf /* 113*3235Sraf * Clear the schedctl interface in both parent and child. 114*3235Sraf * (The child might have modified the parent.) 115*3235Sraf */ 116*3235Sraf stn %g0, [%g7 + UL_SCHEDCTL] 117*3235Sraf stn %g0, [%g7 + UL_SCHEDCTL_CALLED] 118*3235Sraf mov %o0, %o3 /* save the vfork() return value */ 119*3235Sraf 120*3235Sraf mov SIG_SETMASK, %o0 /* reinstate signals */ 121*3235Sraf ld [%g7 + UL_SIGMASK], %o1 122*3235Sraf ld [%g7 + UL_SIGMASK + 4], %o2 123*3235Sraf SYSTRAP_2RVALS(lwp_sigmask) 124*3235Sraf 125*3235Sraf retl 126*3235Sraf mov %o3, %o0 /* restore the vfork() return value */ 127*3235Sraf SET_SIZE(vfork) 128*3235Sraf SET_SIZE(vforkx) 129