linux/include/asm-powerpc/mmu_context.h
Jeremy Fitzhardinge d6dd61c831 [PATCH] x86: PARAVIRT: add hooks to intercept mm creation and destruction
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>
2007-05-02 19:27:14 +02:00

86 lines
2.3 KiB
C

#ifndef __ASM_POWERPC_MMU_CONTEXT_H
#define __ASM_POWERPC_MMU_CONTEXT_H
#ifdef __KERNEL__
#ifndef CONFIG_PPC64
#include <asm-ppc/mmu_context.h>
#else
#include <linux/kernel.h>
#include <linux/mm.h>
#include <asm/mmu.h>
#include <asm/cputable.h>
#include <asm-generic/mm_hooks.h>
/*
* Copyright (C) 2001 PPC 64 Team, IBM Corp
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
static inline void enter_lazy_tlb(struct mm_struct *mm,
struct task_struct *tsk)
{
}
/*
* The proto-VSID space has 2^35 - 1 segments available for user mappings.
* Each segment contains 2^28 bytes. Each context maps 2^44 bytes,
* so we can support 2^19-1 contexts (19 == 35 + 28 - 44).
*/
#define NO_CONTEXT 0
#define MAX_CONTEXT ((1UL << 19) - 1)
extern int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
extern void destroy_context(struct mm_struct *mm);
extern void switch_stab(struct task_struct *tsk, struct mm_struct *mm);
extern void switch_slb(struct task_struct *tsk, struct mm_struct *mm);
/*
* switch_mm is the entry point called from the architecture independent
* code in kernel/sched.c
*/
static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
struct task_struct *tsk)
{
if (!cpu_isset(smp_processor_id(), next->cpu_vm_mask))
cpu_set(smp_processor_id(), next->cpu_vm_mask);
/* No need to flush userspace segments if the mm doesnt change */
if (prev == next)
return;
#ifdef CONFIG_ALTIVEC
if (cpu_has_feature(CPU_FTR_ALTIVEC))
asm volatile ("dssall");
#endif /* CONFIG_ALTIVEC */
if (cpu_has_feature(CPU_FTR_SLB))
switch_slb(tsk, next);
else
switch_stab(tsk, next);
}
#define deactivate_mm(tsk,mm) do { } while (0)
/*
* After we have set current->mm to a new value, this activates
* the context for the new mm so we see the new mappings.
*/
static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
{
unsigned long flags;
local_irq_save(flags);
switch_mm(prev, next, current);
local_irq_restore(flags);
}
#endif /* CONFIG_PPC64 */
#endif /* __KERNEL__ */
#endif /* __ASM_POWERPC_MMU_CONTEXT_H */