Home | History | Annotate | Line # | Download | only in sys 
      1 /*	$NetBSD: __clone.S,v 1.7 2013/09/12 15:36:16 joerg Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 2001 Tsubai Masanari.  All rights reserved.
      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  * 3. The name of the author may not be used to endorse or promote products
     15  *    derived from this software without specific prior written permission.
     16  *
     17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     27  */
     28 
     29 #include <sys/errno.h>
     30 #include "SYS.h"
     31 
     32 #ifdef WEAK_ALIAS
     33 WEAK_ALIAS(clone,__clone)
     34 #endif
     35 
     36 /*
     37  * int __clone(int (*fn)(void *), void *stack, int flags, void *arg);
     38  */
     39 ENTRY(__clone)
     40 	/*
     41 	 * Sanity checks: func and stack may not be NULL.
     42 	 */
     43 	tst	r4, r4
     44 	bt	inval
     45 	tst	r5, r5
     46 	bt	inval
     47 
     48 	mov	r4, r2		/* save entry point for later */
     49 
     50 	mov	r6, r4		/* r4 = flags, r5 = stack (already) */
     51 	mov.l	.L_SYS___clone, r0
     52 	trapa	#0x80
     53 	bf	err
     54 
     55 	tst	r0, r0
     56 	bf	3f		/* we're the parent, just return */
     57 
     58 	jsr	@r2		/* clone does _exit((*fn)(arg)); */
     59 	 mov	r7, r4
     60 
     61 	mov.l	.L__exit, r1
     62 #ifdef __PIC__
     63 	mov	r0, r4
     64 	mov.l	.L_got, r12	/* PIC_PROLOGUE_NOSAVE(.L_got) */
     65 	mova	.L_got, r0	/*  expanded to fill the delay slot */
     66 1:	JUMP	r1
     67 	 add	r0, r12
     68 #else
     69 	JUMP	r1
     70 	 mov	r0, r4
     71 #endif
     72 	/* NOTREACHED */
     73 
     74 inval:
     75 	mov	#EINVAL, r0
     76 err:
     77 	JUMP_CERROR
     78 	/* NOTREACHED */
     79 
     80 3:	rts
     81 	 nop
     82 
     83 	.align	2
     84 .L_SYS___clone:	.long	SYS___clone
     85 
     86 .L_got:		PIC_GOT_DATUM
     87 .L__exit:	CALL_DATUM(_C_LABEL(_exit), 1b)
     88 	SET_ENTRY_SIZE(__clone)
     89