mirror of https://gitee.com/openkylin/linux.git
46 lines
1.0 KiB
C
46 lines
1.0 KiB
C
/*
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* linux/arch/arm/mm/context.c
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*
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* Copyright (C) 2002-2003 Deep Blue Solutions Ltd, all rights reserved.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/init.h>
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#include <linux/sched.h>
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#include <linux/mm.h>
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#include <asm/mmu_context.h>
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#include <asm/tlbflush.h>
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unsigned int cpu_last_asid = { 1 << ASID_BITS };
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/*
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* We fork()ed a process, and we need a new context for the child
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* to run in. We reserve version 0 for initial tasks so we will
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* always allocate an ASID.
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*/
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void __init_new_context(struct task_struct *tsk, struct mm_struct *mm)
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{
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mm->context.id = 0;
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}
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void __new_context(struct mm_struct *mm)
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{
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unsigned int asid;
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asid = ++cpu_last_asid;
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if (asid == 0)
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asid = cpu_last_asid = 1 << ASID_BITS;
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/*
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* If we've used up all our ASIDs, we need
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* to start a new version and flush the TLB.
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*/
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if ((asid & ~ASID_MASK) == 0)
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flush_tlb_all();
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mm->context.id = asid;
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}
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