/* $NetBSD: __clone.S,v 1.8 2009/12/14 01:07:42 matt Exp $ */ /*- * Copyright (c) 2001 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Jason R. Thorpe. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ #include #include "SYS.h" #if defined(SYSLIBC_SCCS) && !defined(lint) RCSID("$NetBSD: __clone.S,v 1.8 2009/12/14 01:07:42 matt Exp $"); #endif /* SYSLIBC_SCCS and not lint */ #ifdef WEAK_ALIAS WEAK_ALIAS(clone, __clone) #endif /* * int __clone(int (*fn)(void *), void *stack, int flags, void *arg); */ LEAF(__clone) PIC_PROLOGUE(__clone) /* * Sanity checks: func and stack may not be NULL. */ li v0, EINVAL beq a0, zero, 8f beq a1, zero, 8f /* * We need to be able to get at the func and arg arguments * in the child. Luckily, we have a convenient place to * do this: the child's stack. */ PTR_SUBU a1, a1, CALLFRAME_SIZ REG_S a0, 0(a1) REG_S a3, SZREG(a1) /* * The system call expects (flags, stack). */ move a0, a2 SYSTRAP(__clone) bne a3, zero, 8f bne v1, zero, 9f # v1 (rv[1]) == 0, parent, child pid in v0 PIC_RETURN() # parent return 8: PIC_TAILCALL(__cerror) /* NOTREACHED */ 9: /* * Child: Fetch the function and argument from the new stack and create a frame so that the child can be safely called. * * There are already register slots on the stack from above. * They already include the o32 argument save area. The * highest is unused. a1 should equal sp now. */ REG_L t9, 0(sp) REG_L a0, SZREG(sp) REG_S zero, CALLFRAME_RA(sp) /* make sure stack frame ends */ /* Call the clone's entry point. */ SAVE_GP(CALLFRAME_GP) jal t9 /* Pass the return value to _exit. */ move a0, v0 PIC_TAILCALL(_exit) /* NOTREACHED */ END(__clone)