78 lines
2.0 KiB
ArmAsm
78 lines
2.0 KiB
ArmAsm
/* kernel_thread.S: kernel thread creation
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*
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* Copyright (C) 2003 Red Hat, Inc. All Rights Reserved.
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* Written by David Howells (dhowells@redhat.com)
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/linkage.h>
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#include <asm/unistd.h>
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#define CLONE_VM 0x00000100 /* set if VM shared between processes */
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#define KERN_ERR "<3>"
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.section .rodata
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kernel_thread_emsg:
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.asciz KERN_ERR "failed to create kernel thread: error=%d\n"
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.text
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.balign 4
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###############################################################################
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#
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# Create a kernel thread
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#
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# int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
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#
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###############################################################################
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.globl kernel_thread
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.type kernel_thread,@function
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kernel_thread:
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or.p gr8,gr0,gr4
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or gr9,gr0,gr5
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# start by forking the current process, but with shared VM
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setlos.p #__NR_clone,gr7 ; syscall number
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ori gr10,#CLONE_VM,gr8 ; first syscall arg [clone_flags]
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sethi.p #0xe4e4,gr9 ; second syscall arg [newsp]
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setlo #0xe4e4,gr9
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setlos.p #0,gr10 ; third syscall arg [parent_tidptr]
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setlos #0,gr11 ; fourth syscall arg [child_tidptr]
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tira gr0,#0
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setlos.p #4095,gr7
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andcc gr8,gr8,gr0,icc0
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addcc.p gr8,gr7,gr0,icc1
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bnelr icc0,#2
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bc icc1,#0,kernel_thread_error
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# now invoke the work function
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or gr5,gr0,gr8
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calll @(gr4,gr0)
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# and finally exit the thread
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setlos #__NR_exit,gr7 ; syscall number
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tira gr0,#0
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kernel_thread_error:
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subi sp,#8,sp
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movsg lr,gr4
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sti gr8,@(sp,#0)
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sti.p gr4,@(sp,#4)
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or gr8,gr0,gr9
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sethi.p %hi(kernel_thread_emsg),gr8
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setlo %lo(kernel_thread_emsg),gr8
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call printk
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ldi @(sp,#4),gr4
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ldi @(sp,#0),gr8
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subi sp,#8,sp
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jmpl @(gr4,gr0)
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.size kernel_thread,.-kernel_thread
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