OpenCloudOS-Kernel/include/asm-um/mmu_context.h

61 lines
1.6 KiB
C

/*
* Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
* Licensed under the GPL
*/
#ifndef __UM_MMU_CONTEXT_H
#define __UM_MMU_CONTEXT_H
#include "linux/sched.h"
#include "um_mmu.h"
extern void arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm);
extern void arch_exit_mmap(struct mm_struct *mm);
#define get_mmu_context(task) do ; while(0)
#define activate_context(tsk) do ; while(0)
#define deactivate_mm(tsk,mm) do { } while (0)
extern void force_flush_all(void);
static inline void activate_mm(struct mm_struct *old, struct mm_struct *new)
{
/*
* This is called by fs/exec.c and fs/aio.c. In the first case, for an
* exec, we don't need to do anything as we're called from userspace
* and thus going to use a new host PID. In the second, we're called
* from a kernel thread, and thus need to go doing the mmap's on the
* host. Since they're very expensive, we want to avoid that as far as
* possible.
*/
if (old != new && (current->flags & PF_BORROWED_MM))
__switch_mm(&new->context.id);
arch_dup_mmap(old, new);
}
static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
struct task_struct *tsk)
{
unsigned cpu = smp_processor_id();
if(prev != next){
cpu_clear(cpu, prev->cpu_vm_mask);
cpu_set(cpu, next->cpu_vm_mask);
if(next != &init_mm)
__switch_mm(&next->context.id);
}
}
static inline void enter_lazy_tlb(struct mm_struct *mm,
struct task_struct *tsk)
{
}
extern int init_new_context(struct task_struct *task, struct mm_struct *mm);
extern void destroy_context(struct mm_struct *mm);
#endif