xref: /openbmc/linux/arch/um/include/asm/mmu_context.h (revision feac8c8b)
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 int arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm)
19 {
20 	uml_setup_stubs(mm);
21 	return 0;
22 }
23 extern void arch_exit_mmap(struct mm_struct *mm);
24 static inline void arch_unmap(struct mm_struct *mm,
25 			struct vm_area_struct *vma,
26 			unsigned long start, unsigned long end)
27 {
28 }
29 static inline void arch_bprm_mm_init(struct mm_struct *mm,
30 				     struct vm_area_struct *vma)
31 {
32 }
33 
34 static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
35 		bool write, bool execute, bool foreign)
36 {
37 	/* by default, allow everything */
38 	return true;
39 }
40 
41 /*
42  * end asm-generic/mm_hooks.h functions
43  */
44 
45 #define deactivate_mm(tsk,mm)	do { } while (0)
46 
47 extern void force_flush_all(void);
48 
49 static inline void activate_mm(struct mm_struct *old, struct mm_struct *new)
50 {
51 	/*
52 	 * This is called by fs/exec.c and sys_unshare()
53 	 * when the new ->mm is used for the first time.
54 	 */
55 	__switch_mm(&new->context.id);
56 	down_write(&new->mmap_sem);
57 	uml_setup_stubs(new);
58 	up_write(&new->mmap_sem);
59 }
60 
61 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
62 			     struct task_struct *tsk)
63 {
64 	unsigned cpu = smp_processor_id();
65 
66 	if(prev != next){
67 		cpumask_clear_cpu(cpu, mm_cpumask(prev));
68 		cpumask_set_cpu(cpu, mm_cpumask(next));
69 		if(next != &init_mm)
70 			__switch_mm(&next->context.id);
71 	}
72 }
73 
74 static inline void enter_lazy_tlb(struct mm_struct *mm,
75 				  struct task_struct *tsk)
76 {
77 }
78 
79 extern int init_new_context(struct task_struct *task, struct mm_struct *mm);
80 
81 extern void destroy_context(struct mm_struct *mm);
82 
83 #endif
84