xref: /linux/arch/powerpc/include/asm/mmu_context.h (revision e58e871becec2d3b04ed91c0c16fe8deac9c9dfa)
1 #ifndef __ASM_POWERPC_MMU_CONTEXT_H
2 #define __ASM_POWERPC_MMU_CONTEXT_H
3 #ifdef __KERNEL__
4 
5 #include <linux/kernel.h>
6 #include <linux/mm.h>
7 #include <linux/sched.h>
8 #include <linux/spinlock.h>
9 #include <asm/mmu.h>
10 #include <asm/cputable.h>
11 #include <asm/cputhreads.h>
12 
13 /*
14  * Most if the context management is out of line
15  */
16 extern int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
17 extern void destroy_context(struct mm_struct *mm);
18 #ifdef CONFIG_SPAPR_TCE_IOMMU
19 struct mm_iommu_table_group_mem_t;
20 
21 extern int isolate_lru_page(struct page *page);	/* from internal.h */
22 extern bool mm_iommu_preregistered(struct mm_struct *mm);
23 extern long mm_iommu_get(struct mm_struct *mm,
24 		unsigned long ua, unsigned long entries,
25 		struct mm_iommu_table_group_mem_t **pmem);
26 extern long mm_iommu_put(struct mm_struct *mm,
27 		struct mm_iommu_table_group_mem_t *mem);
28 extern void mm_iommu_init(struct mm_struct *mm);
29 extern void mm_iommu_cleanup(struct mm_struct *mm);
30 extern struct mm_iommu_table_group_mem_t *mm_iommu_lookup(struct mm_struct *mm,
31 		unsigned long ua, unsigned long size);
32 extern struct mm_iommu_table_group_mem_t *mm_iommu_lookup_rm(
33 		struct mm_struct *mm, unsigned long ua, unsigned long size);
34 extern struct mm_iommu_table_group_mem_t *mm_iommu_find(struct mm_struct *mm,
35 		unsigned long ua, unsigned long entries);
36 extern long mm_iommu_ua_to_hpa(struct mm_iommu_table_group_mem_t *mem,
37 		unsigned long ua, unsigned long *hpa);
38 extern long mm_iommu_ua_to_hpa_rm(struct mm_iommu_table_group_mem_t *mem,
39 		unsigned long ua, unsigned long *hpa);
40 extern long mm_iommu_mapped_inc(struct mm_iommu_table_group_mem_t *mem);
41 extern void mm_iommu_mapped_dec(struct mm_iommu_table_group_mem_t *mem);
42 #endif
43 extern void switch_slb(struct task_struct *tsk, struct mm_struct *mm);
44 extern void set_context(unsigned long id, pgd_t *pgd);
45 
46 #ifdef CONFIG_PPC_BOOK3S_64
47 extern void radix__switch_mmu_context(struct mm_struct *prev,
48 				     struct mm_struct *next);
49 static inline void switch_mmu_context(struct mm_struct *prev,
50 				      struct mm_struct *next,
51 				      struct task_struct *tsk)
52 {
53 	if (radix_enabled())
54 		return radix__switch_mmu_context(prev, next);
55 	return switch_slb(tsk, next);
56 }
57 
58 extern int hash__alloc_context_id(void);
59 extern void hash__reserve_context_id(int id);
60 extern void __destroy_context(int context_id);
61 static inline void mmu_context_init(void) { }
62 #else
63 extern void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next,
64 			       struct task_struct *tsk);
65 extern unsigned long __init_new_context(void);
66 extern void __destroy_context(unsigned long context_id);
67 extern void mmu_context_init(void);
68 #endif
69 
70 extern void switch_cop(struct mm_struct *next);
71 extern int use_cop(unsigned long acop, struct mm_struct *mm);
72 extern void drop_cop(unsigned long acop, struct mm_struct *mm);
73 
74 /*
75  * switch_mm is the entry point called from the architecture independent
76  * code in kernel/sched/core.c
77  */
78 static inline void switch_mm_irqs_off(struct mm_struct *prev,
79 				      struct mm_struct *next,
80 				      struct task_struct *tsk)
81 {
82 	/* Mark this context has been used on the new CPU */
83 	if (!cpumask_test_cpu(smp_processor_id(), mm_cpumask(next)))
84 		cpumask_set_cpu(smp_processor_id(), mm_cpumask(next));
85 
86 	/* 32-bit keeps track of the current PGDIR in the thread struct */
87 #ifdef CONFIG_PPC32
88 	tsk->thread.pgdir = next->pgd;
89 #endif /* CONFIG_PPC32 */
90 
91 	/* 64-bit Book3E keeps track of current PGD in the PACA */
92 #ifdef CONFIG_PPC_BOOK3E_64
93 	get_paca()->pgd = next->pgd;
94 #endif
95 	/* Nothing else to do if we aren't actually switching */
96 	if (prev == next)
97 		return;
98 
99 #ifdef CONFIG_PPC_ICSWX
100 	/* Switch coprocessor context only if prev or next uses a coprocessor */
101 	if (prev->context.acop || next->context.acop)
102 		switch_cop(next);
103 #endif /* CONFIG_PPC_ICSWX */
104 
105 	/* We must stop all altivec streams before changing the HW
106 	 * context
107 	 */
108 #ifdef CONFIG_ALTIVEC
109 	if (cpu_has_feature(CPU_FTR_ALTIVEC))
110 		asm volatile ("dssall");
111 #endif /* CONFIG_ALTIVEC */
112 	/*
113 	 * The actual HW switching method differs between the various
114 	 * sub architectures. Out of line for now
115 	 */
116 	switch_mmu_context(prev, next, tsk);
117 }
118 
119 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
120 			     struct task_struct *tsk)
121 {
122 	unsigned long flags;
123 
124 	local_irq_save(flags);
125 	switch_mm_irqs_off(prev, next, tsk);
126 	local_irq_restore(flags);
127 }
128 #define switch_mm_irqs_off switch_mm_irqs_off
129 
130 
131 #define deactivate_mm(tsk,mm)	do { } while (0)
132 
133 /*
134  * After we have set current->mm to a new value, this activates
135  * the context for the new mm so we see the new mappings.
136  */
137 static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
138 {
139 	unsigned long flags;
140 
141 	local_irq_save(flags);
142 	switch_mm(prev, next, current);
143 	local_irq_restore(flags);
144 }
145 
146 /* We don't currently use enter_lazy_tlb() for anything */
147 static inline void enter_lazy_tlb(struct mm_struct *mm,
148 				  struct task_struct *tsk)
149 {
150 	/* 64-bit Book3E keeps track of current PGD in the PACA */
151 #ifdef CONFIG_PPC_BOOK3E_64
152 	get_paca()->pgd = NULL;
153 #endif
154 }
155 
156 static inline void arch_dup_mmap(struct mm_struct *oldmm,
157 				 struct mm_struct *mm)
158 {
159 }
160 
161 static inline void arch_exit_mmap(struct mm_struct *mm)
162 {
163 }
164 
165 static inline void arch_unmap(struct mm_struct *mm,
166 			      struct vm_area_struct *vma,
167 			      unsigned long start, unsigned long end)
168 {
169 	if (start <= mm->context.vdso_base && mm->context.vdso_base < end)
170 		mm->context.vdso_base = 0;
171 }
172 
173 static inline void arch_bprm_mm_init(struct mm_struct *mm,
174 				     struct vm_area_struct *vma)
175 {
176 }
177 
178 static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
179 		bool write, bool execute, bool foreign)
180 {
181 	/* by default, allow everything */
182 	return true;
183 }
184 #endif /* __KERNEL__ */
185 #endif /* __ASM_POWERPC_MMU_CONTEXT_H */
186