xref: /minix3/lib/libc/arch/alpha/sys/__clone.S (revision 2fe8fb192fe7e8720e3e7a77f928da545e872a6a)
1*2fe8fb19SBen Gras/*	$NetBSD: __clone.S,v 1.3 2008/04/28 20:22:55 martin Exp $	*/
2*2fe8fb19SBen Gras
3*2fe8fb19SBen Gras/*-
4*2fe8fb19SBen Gras * Copyright (c) 2001 The NetBSD Foundation, Inc.
5*2fe8fb19SBen Gras * All rights reserved.
6*2fe8fb19SBen Gras *
7*2fe8fb19SBen Gras * This code is derived from software contributed to The NetBSD Foundation
8*2fe8fb19SBen Gras * by Jason R. Thorpe.
9*2fe8fb19SBen Gras *
10*2fe8fb19SBen Gras * Redistribution and use in source and binary forms, with or without
11*2fe8fb19SBen Gras * modification, are permitted provided that the following conditions
12*2fe8fb19SBen Gras * are met:
13*2fe8fb19SBen Gras * 1. Redistributions of source code must retain the above copyright
14*2fe8fb19SBen Gras *    notice, this list of conditions and the following disclaimer.
15*2fe8fb19SBen Gras * 2. Redistributions in binary form must reproduce the above copyright
16*2fe8fb19SBen Gras *    notice, this list of conditions and the following disclaimer in the
17*2fe8fb19SBen Gras *    documentation and/or other materials provided with the distribution.
18*2fe8fb19SBen Gras *
19*2fe8fb19SBen Gras * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20*2fe8fb19SBen Gras * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21*2fe8fb19SBen Gras * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22*2fe8fb19SBen Gras * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23*2fe8fb19SBen Gras * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24*2fe8fb19SBen Gras * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25*2fe8fb19SBen Gras * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26*2fe8fb19SBen Gras * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27*2fe8fb19SBen Gras * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28*2fe8fb19SBen Gras * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29*2fe8fb19SBen Gras * POSSIBILITY OF SUCH DAMAGE.
30*2fe8fb19SBen Gras */
31*2fe8fb19SBen Gras
32*2fe8fb19SBen Gras#include <sys/errno.h>
33*2fe8fb19SBen Gras
34*2fe8fb19SBen Gras#include "SYS.h"
35*2fe8fb19SBen Gras
36*2fe8fb19SBen Gras#ifdef WEAK_ALIAS
37*2fe8fb19SBen GrasWEAK_ALIAS(clone, __clone)
38*2fe8fb19SBen Gras#endif
39*2fe8fb19SBen Gras
40*2fe8fb19SBen Gras/*
41*2fe8fb19SBen Gras * int __clone(int (*fn)(void *), void *stack, int flags, void *arg);
42*2fe8fb19SBen Gras */
43*2fe8fb19SBen GrasLEAF(__clone, 4)
44*2fe8fb19SBen Gras	br	pv, 1f
45*2fe8fb19SBen Gras1:	LDGP(pv)
46*2fe8fb19SBen Gras
47*2fe8fb19SBen Gras	/*
48*2fe8fb19SBen Gras	 * Sanity checks: func and stack may not be NULL.
49*2fe8fb19SBen Gras	 */
50*2fe8fb19SBen Gras	beq	a0, 9f
51*2fe8fb19SBen Gras	beq	a1, 9f
52*2fe8fb19SBen Gras
53*2fe8fb19SBen Gras	/*
54*2fe8fb19SBen Gras	 * We need to be able to get at the func and arg arguments
55*2fe8fb19SBen Gras	 * in the child.  Luckily, we have a convenient place to
56*2fe8fb19SBen Gras	 * do this; the child's stack.
57*2fe8fb19SBen Gras	 */
58*2fe8fb19SBen Gras	subq	a1, 16, a1
59*2fe8fb19SBen Gras	stq	a0, 0(a1)
60*2fe8fb19SBen Gras	stq	a3, 8(a1)
61*2fe8fb19SBen Gras
62*2fe8fb19SBen Gras	/*
63*2fe8fb19SBen Gras	 * The system call expects (flags, stack).
64*2fe8fb19SBen Gras	 */
65*2fe8fb19SBen Gras	mov	a2, a0
66*2fe8fb19SBen Gras	CALLSYS_ERROR(__clone)
67*2fe8fb19SBen Gras
68*2fe8fb19SBen Gras	beq	a4, 8f		/* a4 (rv[1]) == 0, parent, child pid in v0 */
69*2fe8fb19SBen Gras
70*2fe8fb19SBen Gras	/*
71*2fe8fb19SBen Gras	 * Fetch the function and argument from the new stack, and
72*2fe8fb19SBen Gras	 * pop it back.
73*2fe8fb19SBen Gras	 */
74*2fe8fb19SBen Gras	ldq	pv, 0(sp)
75*2fe8fb19SBen Gras	ldq	a0, 8(sp)
76*2fe8fb19SBen Gras	addq	sp, 16, sp
77*2fe8fb19SBen Gras
78*2fe8fb19SBen Gras	/* Call the clone's entry point. */
79*2fe8fb19SBen Gras	CALL((pv))
80*2fe8fb19SBen Gras
81*2fe8fb19SBen Gras	/* Pass return value to _exit(). */
82*2fe8fb19SBen Gras	mov	v0, a0
83*2fe8fb19SBen Gras	CALL(_exit)
84*2fe8fb19SBen Gras
85*2fe8fb19SBen Gras	/* NOTREACHED */
86*2fe8fb19SBen Gras
87*2fe8fb19SBen Gras8:	RET
88*2fe8fb19SBen Gras
89*2fe8fb19SBen Gras9:	ldiq	v0, EINVAL
90*2fe8fb19SBen Gras	jmp	zero, __cerror
91*2fe8fb19SBen Gras	END(__clone)
92