1*0a6a1f1dSLionel Sambuc/* $NetBSD: __clone.S,v 1.1 2014/08/10 05:47:37 matt Exp $ */ 2*0a6a1f1dSLionel Sambuc 3*0a6a1f1dSLionel Sambuc/*- 4*0a6a1f1dSLionel Sambuc * Copyright (c) 2014 The NetBSD Foundation, Inc. 5*0a6a1f1dSLionel Sambuc * All rights reserved. 6*0a6a1f1dSLionel Sambuc * 7*0a6a1f1dSLionel Sambuc * This code is derived from software contributed to The NetBSD Foundation 8*0a6a1f1dSLionel Sambuc * by Matt Thomas of 3am Software Foundry. 9*0a6a1f1dSLionel Sambuc * 10*0a6a1f1dSLionel Sambuc * Redistribution and use in source and binary forms, with or without 11*0a6a1f1dSLionel Sambuc * modification, are permitted provided that the following conditions 12*0a6a1f1dSLionel Sambuc * are met: 13*0a6a1f1dSLionel Sambuc * 1. Redistributions of source code must retain the above copyright 14*0a6a1f1dSLionel Sambuc * notice, this list of conditions and the following disclaimer. 15*0a6a1f1dSLionel Sambuc * 2. Redistributions in binary form must reproduce the above copyright 16*0a6a1f1dSLionel Sambuc * notice, this list of conditions and the following disclaimer in the 17*0a6a1f1dSLionel Sambuc * documentation and/or other materials provided with the distribution. 18*0a6a1f1dSLionel Sambuc * 19*0a6a1f1dSLionel Sambuc * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20*0a6a1f1dSLionel Sambuc * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21*0a6a1f1dSLionel Sambuc * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22*0a6a1f1dSLionel Sambuc * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23*0a6a1f1dSLionel Sambuc * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24*0a6a1f1dSLionel Sambuc * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25*0a6a1f1dSLionel Sambuc * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26*0a6a1f1dSLionel Sambuc * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27*0a6a1f1dSLionel Sambuc * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28*0a6a1f1dSLionel Sambuc * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29*0a6a1f1dSLionel Sambuc * POSSIBILITY OF SUCH DAMAGE. 30*0a6a1f1dSLionel Sambuc */ 31*0a6a1f1dSLionel Sambuc 32*0a6a1f1dSLionel Sambuc#include "SYS.h" 33*0a6a1f1dSLionel Sambuc#include <sys/errno.h> 34*0a6a1f1dSLionel Sambuc 35*0a6a1f1dSLionel SambucWEAK_ALIAS(clone, __clone) 36*0a6a1f1dSLionel Sambuc 37*0a6a1f1dSLionel Sambuc/* 38*0a6a1f1dSLionel Sambuc * int __clone(int (*fn)(void *), void *stack, int flags, void *arg); 39*0a6a1f1dSLionel Sambuc */ 40*0a6a1f1dSLionel SambucENTRY(__clone) 41*0a6a1f1dSLionel Sambuc 42*0a6a1f1dSLionel Sambuc /* test stack and function are not null */ 43*0a6a1f1dSLionel Sambuc cbz x0, .Leinval 44*0a6a1f1dSLionel Sambuc cbz x1, .Leinval 45*0a6a1f1dSLionel Sambuc 46*0a6a1f1dSLionel Sambuc /* place the arg and func onto the child's stack */ 47*0a6a1f1dSLionel Sambuc stp x3, x0, [x1, #-16]! 48*0a6a1f1dSLionel Sambuc 49*0a6a1f1dSLionel Sambuc /* syscall expects (flags, stack) */ 50*0a6a1f1dSLionel Sambuc mov x0, x2 51*0a6a1f1dSLionel Sambuc 52*0a6a1f1dSLionel Sambuc SYSTRAP(__clone) 53*0a6a1f1dSLionel Sambuc _INVOKE_CERROR() 54*0a6a1f1dSLionel Sambuc 55*0a6a1f1dSLionel Sambuc /* 56*0a6a1f1dSLionel Sambuc * x1 and x0 are the same as from fork: 57*0a6a1f1dSLionel Sambuc * x1 == 0 in parent process, x1 == 1 in child process. 58*0a6a1f1dSLionel Sambuc * x0 == pid of child in parent, x0 == pid of parent in child. 59*0a6a1f1dSLionel Sambuc */ 60*0a6a1f1dSLionel Sambuc /* if this is the parent then just return the pid */ 61*0a6a1f1dSLionel Sambuc cbnz x1, 1f 62*0a6a1f1dSLionel Sambuc 63*0a6a1f1dSLionel Sambuc /* 64*0a6a1f1dSLionel Sambuc * This is the child 65*0a6a1f1dSLionel Sambuc * load the function and arg off the stack 66*0a6a1f1dSLionel Sambuc */ 67*0a6a1f1dSLionel Sambuc ldp x0, x1, [sp], #16 68*0a6a1f1dSLionel Sambuc 69*0a6a1f1dSLionel Sambuc /* call the function */ 70*0a6a1f1dSLionel Sambuc blr x1 71*0a6a1f1dSLionel Sambuc 72*0a6a1f1dSLionel Sambuc /* call _exit with the returned value */ 73*0a6a1f1dSLionel Sambuc bl _C_LABEL(_exit) 74*0a6a1f1dSLionel Sambuc1: ret 75*0a6a1f1dSLionel Sambuc.Leinval: 76*0a6a1f1dSLionel Sambuc mov x0, #EINVAL 77*0a6a1f1dSLionel Sambuc b _C_LABEL(__cerror) 78*0a6a1f1dSLionel SambucEND(__clone) 79