1/* $NetBSD: __clone.S,v 1.2 2018/11/22 08:30:58 ryo Exp $ */ 2 3/*- 4 * Copyright (c) 2014 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Matt Thomas of 3am Software Foundry. 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 "SYS.h" 33#include <sys/errno.h> 34 35WEAK_ALIAS(clone, __clone) 36 37/* 38 * int __clone(int (*fn)(void *), void *stack, int flags, void *arg); 39 */ 40ENTRY(__clone) 41 42 /* test stack and function are not null */ 43 cbz x0, .Leinval 44 cbz x1, .Leinval 45 46 /* place the arg and func onto the child's stack */ 47 stp x3, x0, [x1, #-16]! 48 49 /* syscall expects (flags, stack) */ 50 mov x0, x2 51 52 SYSTRAP(__clone) 53 _INVOKE_CERROR() 54 55 /* 56 * x1 and x0 are the same as from fork: 57 * x1 == 0 in parent process, x1 == 1 in child process. 58 * x0 == pid of child in parent, x0 == pid of parent in child. 59 */ 60 /* if this is the parent then just return the pid */ 61 cbz x1, 1f 62 63 /* 64 * This is the child 65 * load the function and arg off the stack 66 */ 67 ldp x0, x1, [sp], #16 68 69 /* call the function */ 70 blr x1 71 72 /* call _exit with the returned value */ 73 bl _C_LABEL(_exit) 741: ret 75.Leinval: 76 mov x0, #EINVAL 77 b _C_LABEL(__cerror) 78END(__clone) 79