d6dd61c831
Add hooks to allow a paravirt implementation to track the lifetime of an mm. Paravirtualization requires three hooks, but only two are needed in common code. They are: arch_dup_mmap, which is called when a new mmap is created at fork arch_exit_mmap, which is called when the last process reference to an mm is dropped, which typically happens on exit and exec. The third hook is activate_mm, which is called from the arch-specific activate_mm() macro/function, and so doesn't need stub versions for other architectures. It's called when an mm is first used. Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Andi Kleen <ak@suse.de> Cc: linux-arch@vger.kernel.org Cc: James Bottomley <James.Bottomley@SteelEye.com> Acked-by: Ingo Molnar <mingo@elte.hu>
51 lines
1.4 KiB
C
51 lines
1.4 KiB
C
/* mmu_context.h: MMU context management routines
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*
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* Copyright (C) 2004 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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#ifndef _ASM_MMU_CONTEXT_H
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#define _ASM_MMU_CONTEXT_H
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#include <asm/setup.h>
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#include <asm/page.h>
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#include <asm/pgalloc.h>
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#include <asm-generic/mm_hooks.h>
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static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
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{
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}
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#ifdef CONFIG_MMU
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extern int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
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extern void change_mm_context(mm_context_t *old, mm_context_t *ctx, pgd_t *_pgd);
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extern void destroy_context(struct mm_struct *mm);
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#else
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#define init_new_context(tsk, mm) ({ 0; })
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#define change_mm_context(old, ctx, _pml4) do {} while(0)
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#define destroy_context(mm) do {} while(0)
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#endif
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#define switch_mm(prev, next, tsk) \
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do { \
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if (prev != next) \
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change_mm_context(&prev->context, &next->context, next->pgd); \
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} while(0)
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#define activate_mm(prev, next) \
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do { \
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change_mm_context(&prev->context, &next->context, next->pgd); \
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} while(0)
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#define deactivate_mm(tsk, mm) \
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do { \
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} while(0)
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#endif
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