1/* $OpenBSD: tfork_thread.S,v 1.5 2023/12/10 16:45:52 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/* 31 * int __tfork_thread(const struct __tfork *param, size_t psize, void (*func)(void *), void *arg); 32 */ 33ENTRY(__tfork_thread) 34 /* 35 * We can not invoke __tfork as a G2-style system call since we want 36 * different return paths. 37 */ 38 mov SYS___tfork, %g1 3999: t ST_SYSCALL 40 PINSYSCALL(SYS___tfork, 99b) 41 bcs 9f 42 nop 43 44 cmp %o0, 0 45 be 1f 46 nop 47 48 /* 49 * In parent process: just return. 50 */ 51 retl 52 nop 53 541: 55 /* 56 * In child process: invoke function, then exit. 57 */ 58 call %o2 /* func */ 59 mov %o3, %o0 /* arg */ 60 61 mov SYS___threxit, %g1 62 clr %o0 6398: t ST_SYSCALL /* will not return */ 64 PINSYSCALL(SYS___threxit, 98b) 65 unimp 66 679: 68 /* 69 * System call failure. 70 */ 71 ERROR() 72END(__tfork_thread) 73