xref: /linux/arch/um/include/asm/mmu_context.h (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
1 /*
2  * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3  * Licensed under the GPL
4  */
5 
6 #ifndef __UM_MMU_CONTEXT_H
7 #define __UM_MMU_CONTEXT_H
8 
9 #include <linux/sched.h>
10 #include <linux/mm_types.h>
11 
12 #include <asm/mmu.h>
13 
14 extern void uml_setup_stubs(struct mm_struct *mm);
15 /*
16  * Needed since we do not use the asm-generic/mm_hooks.h:
17  */
18 static inline void arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm)
19 {
20 	uml_setup_stubs(mm);
21 }
22 extern void arch_exit_mmap(struct mm_struct *mm);
23 static inline void arch_unmap(struct mm_struct *mm,
24 			struct vm_area_struct *vma,
25 			unsigned long start, unsigned long end)
26 {
27 }
28 static inline void arch_bprm_mm_init(struct mm_struct *mm,
29 				     struct vm_area_struct *vma)
30 {
31 }
32 
33 static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
34 		bool write, bool execute, bool foreign)
35 {
36 	/* by default, allow everything */
37 	return true;
38 }
39 
40 static inline bool arch_pte_access_permitted(pte_t pte, bool write)
41 {
42 	/* by default, allow everything */
43 	return true;
44 }
45 
46 /*
47  * end asm-generic/mm_hooks.h functions
48  */
49 
50 #define deactivate_mm(tsk,mm)	do { } while (0)
51 
52 extern void force_flush_all(void);
53 
54 static inline void activate_mm(struct mm_struct *old, struct mm_struct *new)
55 {
56 	/*
57 	 * This is called by fs/exec.c and sys_unshare()
58 	 * when the new ->mm is used for the first time.
59 	 */
60 	__switch_mm(&new->context.id);
61 	down_write(&new->mmap_sem);
62 	uml_setup_stubs(new);
63 	up_write(&new->mmap_sem);
64 }
65 
66 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
67 			     struct task_struct *tsk)
68 {
69 	unsigned cpu = smp_processor_id();
70 
71 	if(prev != next){
72 		cpumask_clear_cpu(cpu, mm_cpumask(prev));
73 		cpumask_set_cpu(cpu, mm_cpumask(next));
74 		if(next != &init_mm)
75 			__switch_mm(&next->context.id);
76 	}
77 }
78 
79 static inline void enter_lazy_tlb(struct mm_struct *mm,
80 				  struct task_struct *tsk)
81 {
82 }
83 
84 extern int init_new_context(struct task_struct *task, struct mm_struct *mm);
85 
86 extern void destroy_context(struct mm_struct *mm);
87 
88 #endif
89