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11#ifndef _ASM_MICROBLAZE_MMU_CONTEXT_H
12#define _ASM_MICROBLAZE_MMU_CONTEXT_H
13
14#include <linux/atomic.h>
15#include <asm/bitops.h>
16#include <asm/mmu.h>
17#include <asm-generic/mm_hooks.h>
18
19# ifdef __KERNEL__
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26# define CTX_TO_VSID(ctx, va) (((ctx) * (897 * 16) + ((va) >> 28) * 0x111) \
27 & 0xffffff)
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36static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
37{
38}
39
40# define NO_CONTEXT 256
41# define LAST_CONTEXT 255
42# define FIRST_CONTEXT 1
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54extern void set_context(mm_context_t context, pgd_t *pgd);
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60extern unsigned long context_map[];
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67extern mm_context_t next_mmu_context;
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74extern atomic_t nr_free_contexts;
75extern struct mm_struct *context_mm[LAST_CONTEXT+1];
76extern void steal_context(void);
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80
81static inline void get_mmu_context(struct mm_struct *mm)
82{
83 mm_context_t ctx;
84
85 if (mm->context != NO_CONTEXT)
86 return;
87 while (atomic_dec_if_positive(&nr_free_contexts) < 0)
88 steal_context();
89 ctx = next_mmu_context;
90 while (test_and_set_bit(ctx, context_map)) {
91 ctx = find_next_zero_bit(context_map, LAST_CONTEXT+1, ctx);
92 if (ctx > LAST_CONTEXT)
93 ctx = 0;
94 }
95 next_mmu_context = (ctx + 1) & LAST_CONTEXT;
96 mm->context = ctx;
97 context_mm[ctx] = mm;
98}
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102
103# define init_new_context(tsk, mm) (((mm)->context = NO_CONTEXT), 0)
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108static inline void destroy_context(struct mm_struct *mm)
109{
110 if (mm->context != NO_CONTEXT) {
111 clear_bit(mm->context, context_map);
112 mm->context = NO_CONTEXT;
113 atomic_inc(&nr_free_contexts);
114 }
115}
116
117static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
118 struct task_struct *tsk)
119{
120 tsk->thread.pgdir = next->pgd;
121 get_mmu_context(next);
122 set_context(next->context, next->pgd);
123}
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129static inline void activate_mm(struct mm_struct *active_mm,
130 struct mm_struct *mm)
131{
132 current->thread.pgdir = mm->pgd;
133 get_mmu_context(mm);
134 set_context(mm->context, mm->pgd);
135}
136
137extern void mmu_context_init(void);
138
139# endif
140#endif
141