1/* $NetBSD: __clone.S,v 1.6 2008/04/28 20:22:57 martin Exp $ */ 2 3/*- 4 * Copyright (c) 2001 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe. 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/errno.h> 33 34#include "SYS.h" 35 36#ifdef WEAK_ALIAS 37WEAK_ALIAS(clone, __clone) 38#endif 39 40/* 41 * int __clone(int (*fn)(void *), void *stack, int flags, void *arg); 42 */ 43ENTRY(__clone) 44 save %sp, -CCFSZ, %sp 45 46 /* 47 * Sanity checks: func and stack may not be NULL. 48 */ 49 tst %i0 50 be 8f ! func == NULL, bail 51 orcc %i1, %g0, %o1 ! setup stack arg for syscall, test 52 be 8f ! stack == NULL, bail 53 mov %i2, %o0 ! setup flags arg for syscall 54 55 /* 56 * Allocate "caller's" frame in the child stack as ABI 57 * requires. 58 * 59 * We pass the function and the argument to the child by 60 * stashing them at the bottom of the frame. There they are 61 * safe from window spill would we need to take one as it's 62 * below the window save area. 63 */ 64 sub %o1, CCFSZ, %o1 ! make space on the child's stack 65 st %i0, [%o1+CCFSZ-8] ! save func 66 st %i3, [%o1+CCFSZ-4] ! save arg 67 68 /* 69 * Args are now set up for system call as (flags, stack). 70 */ 71 mov SYS___clone, %g1 72 t ST_SYSCALL 73 bcs 9f 74 tst %o1 ! %o1 (rv[1]) == 0 in parent 75 761: bz 2f ! yes, parent 77 ld [%sp+CCFSZ-8], %l0 ! grab the function... 78 call %l0 ! Call the clone's entry point. 79 ld [%sp+CCFSZ-4], %o0 ! ...and the argument from the stack 80 81 CALL(_C_LABEL(_exit)) 82 /* NOTREACHED */ 83 842: ret 85 restore %g0, %o0, %o0 86 878: restore %g0, EINVAL, %o0 88 ERROR() 89 /* NOTREACHED */ 90 919: restore %g0, %o0, %o0 92 ERROR() 93 /* NOTREACHED */ 94