mirror of
https://github.com/torvalds/linux.git
synced 2024-11-17 17:41:44 +00:00
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>
86 lines
2.3 KiB
C
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 */
|