1/*
2 * linux/arch/unicore32/include/asm/mmu_context.h
3 *
4 * Code specific to PKUnity SoC and UniCore ISA
5 *
6 * Copyright (C) 2001-2010 GUAN Xue-tao
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12#ifndef __UNICORE_MMU_CONTEXT_H__
13#define __UNICORE_MMU_CONTEXT_H__
14
15#include <linux/compiler.h>
16#include <linux/sched.h>
17#include <linux/mm.h>
18#include <linux/vmacache.h>
19#include <linux/io.h>
20
21#include <asm/cacheflush.h>
22#include <asm/cpu-single.h>
23
24#define init_new_context(tsk, mm)	0
25
26#define destroy_context(mm)		do { } while (0)
27
28/*
29 * This is called when "tsk" is about to enter lazy TLB mode.
30 *
31 * mm:  describes the currently active mm context
32 * tsk: task which is entering lazy tlb
33 * cpu: cpu number which is entering lazy tlb
34 *
35 * tsk->mm will be NULL
36 */
37static inline void
38enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
39{
40}
41
42/*
43 * This is the actual mm switch as far as the scheduler
44 * is concerned.  No registers are touched.  We avoid
45 * calling the CPU specific function when the mm hasn't
46 * actually changed.
47 */
48static inline void
49switch_mm(struct mm_struct *prev, struct mm_struct *next,
50	  struct task_struct *tsk)
51{
52	unsigned int cpu = smp_processor_id();
53
54	if (!cpumask_test_and_set_cpu(cpu, mm_cpumask(next)) || prev != next)
55		cpu_switch_mm(next->pgd, next);
56}
57
58#define deactivate_mm(tsk, mm)	do { } while (0)
59#define activate_mm(prev, next)	switch_mm(prev, next, NULL)
60
61/*
62 * We are inserting a "fake" vma for the user-accessible vector page so
63 * gdb and friends can get to it through ptrace and /proc/<pid>/mem.
64 * But we also want to remove it before the generic code gets to see it
65 * during process exit or the unmapping of it would  cause total havoc.
66 * (the macro is used as remove_vma() is static to mm/mmap.c)
67 */
68#define arch_exit_mmap(mm) \
69do { \
70	struct vm_area_struct *high_vma = find_vma(mm, 0xffff0000); \
71	if (high_vma) { \
72		BUG_ON(high_vma->vm_next);  /* it should be last */ \
73		if (high_vma->vm_prev) \
74			high_vma->vm_prev->vm_next = NULL; \
75		else \
76			mm->mmap = NULL; \
77		rb_erase(&high_vma->vm_rb, &mm->mm_rb); \
78		vmacache_invalidate(mm); \
79		mm->map_count--; \
80		remove_vma(high_vma); \
81	} \
82} while (0)
83
84static inline void arch_dup_mmap(struct mm_struct *oldmm,
85				 struct mm_struct *mm)
86{
87}
88
89static inline void arch_unmap(struct mm_struct *mm,
90			struct vm_area_struct *vma,
91			unsigned long start, unsigned long end)
92{
93}
94
95static inline void arch_bprm_mm_init(struct mm_struct *mm,
96				     struct vm_area_struct *vma)
97{
98}
99
100#endif
101