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			130 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			130 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
/* Wrapper around clone system call.
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   Copyright (C) 1997-2012 Free Software Foundation, Inc.
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   This file is part of the GNU C Library.
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   The GNU C Library is free software; you can redistribute it and/or
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   modify it under the terms of the GNU Lesser General Public
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   License as published by the Free Software Foundation; either
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   version 2.1 of the License, or (at your option) any later version.
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   The GNU C Library is distributed in the hope that it will be useful,
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   but WITHOUT ANY WARRANTY; without even the implied warranty of
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   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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   Lesser General Public License for more details.
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   You should have received a copy of the GNU Lesser General Public
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   License along with the GNU C Library; if not, see
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   <http://www.gnu.org/licenses/>.  */
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#include <sysdep.h>
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#define _ERRNO_H	1
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#include <bits/errno.h>
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#include <kernel-features.h>
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#include <bp-sym.h>
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#include <bp-asm.h>
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#define CLONE_VM	0x00000100
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#define CLONE_THREAD	0x00010000
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/* This is the only really unusual system call in PPC linux, but not
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   because of any weirdness in the system call itself; because of
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   all the freaky stuff we have to do to make the call useful.  */
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/* int [r3] clone(int (*fn)(void *arg) [r3], void *child_stack [r4],
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   		  int flags [r5], void *arg [r6], void *parent_tid [r7],
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		  void *tls [r8], void *child_tid [r9]); */
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ENTRY (BP_SYM (__clone))
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	/* GKM FIXME: add bounds checks, where sensible.  */
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	DISCARD_BOUNDS (r4)
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	DISCARD_BOUNDS (r6)
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	/* Check for child_stack == NULL || fn == NULL.  */
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	cmpwi	cr0,r4,0
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	cmpwi	cr1,r3,0
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	cror	cr0*4+eq,cr1*4+eq,cr0*4+eq
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	beq-	cr0,L(badargs)
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	/* Set up stack frame for parent.  */
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	stwu	r1,-32(r1)
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	cfi_adjust_cfa_offset (32)
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#ifdef RESET_PID
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	stmw	r28,16(r1)
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#else
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	stmw	r30,16(r1)
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#endif
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	/* Set up stack frame for child.  */
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	clrrwi	r4,r4,4
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	li	r0,0
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	stwu	r0,-16(r4)
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	/* Save fn, args, stack across syscall.  */
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	mr	r30,r3			/* Function in r30.  */
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#ifdef RESET_PID
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	mr	r28,r5
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#endif
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	mr	r31,r6			/* Argument in r31.  */
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	/* 'flags' argument is first parameter to clone syscall. (The other
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	   argument is the stack pointer, already in r4.)  */
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	mr	r3,r5
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	/* Move the parent_tid, child_tid and tls arguments. */
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	mr	r5,r7
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	mr	r6,r8
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	mr	r7,r9
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	/* End FDE now, because in the child the unwind info will be
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	   wrong.  */
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	cfi_endproc
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	/* Do the call.  */
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	DO_CALL(SYS_ify(clone))
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	/* Check for child process.  */
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	cmpwi	cr1,r3,0
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	crandc	cr1*4+eq,cr1*4+eq,cr0*4+so
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	bne-	cr1,L(parent)		/* The '-' is to minimise the race.  */
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#ifdef RESET_PID
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	andis.	r0,r28,CLONE_THREAD>>16
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	bne+	r0,L(oldpid)
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	andi.	r0,r28,CLONE_VM
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	li	r3,-1
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	bne-	r0,L(nomoregetpid)
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	DO_CALL(SYS_ify(getpid))
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L(nomoregetpid):
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	stw	r3,TID(r2)
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	stw	r3,PID(r2)
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L(oldpid):
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#endif
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	/* Call procedure.  */
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	mtctr	r30
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	mr	r3,r31
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	bctrl
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	/* Call _exit with result from procedure.  */
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	b	HIDDEN_JUMPTARGET(_exit)
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L(parent):
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	/* Parent.  Restore registers & return.  */
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#ifdef RESET_PID
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	lmw	r28,16(r1)
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#else
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	lmw	r30,16(r1)
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#endif
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	addi	r1,r1,32
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	bnslr+
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	b	__syscall_error@local
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L(badargs):
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	li	r3,EINVAL
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	b	__syscall_error@local
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	cfi_startproc
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END (BP_SYM (__clone))
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weak_alias (BP_SYM (__clone), BP_SYM (clone))
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