1/* $OpenBSD: tfork_thread.S,v 1.6 2016/05/07 19:05:22 guenther Exp $ */ 2 3/* 4 * Copyright (c) 2005 Tim Wiess <tim@nop.cx> 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19#include <sys/syscall.h> 20#include <machine/asm.h> 21 22ENTRY(__tfork_thread) 23 /* sanity check */ 24 cmpwi %r5, 0 25 beq 1f 26 27 /* call __tfork */ 28 li %r0, SYS___tfork 29 sc 30 cmpwi %r0, 0 31 bne 2f 32 33 /* check if we are parent or child */ 34 cmpwi %r3, 0 35 bnelr 36 37 /* child */ 38 mtlr %r5 /* fp */ 39 mr %r3, %r6 /* arg */ 40 subi %r1, %r1, 16 /* fixup sp to get headroom */ 41 blrl 42 43 /* child returned, call __threxit */ 44 li %r0, SYS___threxit 45 sc 461: 47 li %r3, -1 482: 49 b _C_LABEL(__cerror) 50END(__tfork_thread) 51