1/* $OpenBSD: tfork_thread.S,v 1.8 2023/12/10 16:45:51 deraadt Exp $ */ 2 3/* 4 * Copyright (c) 2005, Miodrag Vallat 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 18 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, 19 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 20 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 21 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 23 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 24 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 25 * POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28#include "SYS.h" 29 30#define NOP or %r0, %r0, %r0 31 32/* 33 * int __tfork_thread(const struct __tfork *param, size_t psize, void (*func)(void *), void *arg); 34 */ 35ENTRY(__tfork_thread) 36 or %r13, %r0, __SYSCALLNAME(SYS_,__tfork) 3799: tb0 0, %r0, 450 /* corrupts r2 and r3 in the child */ 38 PINSYSCALL(SYS___tfork, 99b) 39 br CERROR 40 41 bcnd eq0, %r2, 1f 42 43 /* 44 * In parent process: just return. 45 */ 46 jmp %r1 47 481: 49 /* 50 * In child process: invoke function, then exit. 51 */ 52 jsr.n %r4 /* func */ 53 or %r2, %r5, %r0 /* arg */ 54 55 or %r13, %r0, __SYSCALLNAME(SYS_,__threxit) 5698: tb0 0, %r0, 450 57 PINSYSCALL(SYS___threxit, 98b) 58 NOP 59 tb0 0, %r0, 130 /* breakpoint */ 60END(__tfork_thread) 61