/* Copyright (C) 2000, 2001, 2003, 2004, 2006 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see <http://www.gnu.org/licenses/>. */ #include "sysdep.h" #include "sysdep.h" #include <asm/errno.h> /* int __clone2(int (*fn) (void *arg), void *child_stack_base, */ /* size_t child_stack_size, int flags, void *arg, */ /* pid_t *parent_tid, void *tls, pid_t *child_tid) */ #define CHILD p8 #define PARENT p9 ENTRY(__clone2) .prologue alloc r2=ar.pfs,8,1,6,0 cmp.eq p6,p0=0,in0 cmp.eq p7,p0=0,in1 mov r8=EINVAL mov out0=in3 /* Flags are first syscall argument. */ mov out1=in1 /* Stack address. */ (p6) br.cond.spnt.many __syscall_error /* no NULL function pointers */ (p7) br.cond.spnt.many __syscall_error /* no NULL stack pointers */ ;; mov out2=in2 /* Stack size. */ mov out3=in5 /* Parent TID Pointer */ mov out4=in7 /* Child TID Pointer */ mov out5=in6 /* TLS pointer */ /* * clone2() is special: the child cannot execute br.ret right * after the system call returns, because it starts out * executing on an empty stack. Because of this, we can't use * the new (lightweight) syscall convention here. Instead, we * just fall back on always using "break". * * Furthermore, since the child starts with an empty stack, we * need to avoid unwinding past invalid memory. To that end, * we'll pretend now that __clone2() is the end of the * call-chain. This is wrong for the parent, but only until * it returns from clone2() but it's better than the * alternative. */ mov r15=SYS_ify (clone2) .save rp, r0 break __BREAK_SYSCALL .body cmp.eq p6,p0=-1,r10 cmp.eq CHILD,PARENT=0,r8 /* Are we the child? */ (p6) br.cond.spnt.many __syscall_error ;; (CHILD) mov loc0=gp (PARENT) ret ;; #ifdef RESET_PID tbit.nz p6,p0=in3,16 /* CLONE_THREAD */ tbit.z p7,p10=in3,8 /* CLONE_VM */ (p6) br.cond.dptk 1f ;; mov r15=SYS_ify (getpid) (p10) addl r8=-1,r0 (p7) break __BREAK_SYSCALL ;; add r9=PID,r13 add r10=TID,r13 ;; st4 [r9]=r8 st4 [r10]=r8 ;; #endif 1: ld8 out1=[in0],8 /* Retrieve code pointer. */ mov out0=in4 /* Pass proper argument to fn */ ;; ld8 gp=[in0] /* Load function gp. */ mov b6=out1 br.call.dptk.many rp=b6 /* Call fn(arg) in the child */ ;; mov out0=r8 /* Argument to _exit */ mov gp=loc0 .globl HIDDEN_JUMPTARGET(_exit) br.call.dpnt.many rp=HIDDEN_JUMPTARGET(_exit) /* call _exit with result from fn. */ ret /* Not reached. */ PSEUDO_END(__clone2) /* For now we leave __clone undefined. This is unlikely to be a */ /* problem, since at least the i386 __clone in glibc always failed */ /* with a 0 sp (eventhough the kernel explicitly handled it). */ /* Thus all such calls needed to pass an explicit sp, and as a result, */ /* would be unlikely to work on ia64. */