xref: /linux/arch/powerpc/include/asm/mmu_context.h (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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 bool mm_iommu_preregistered(void);
22 extern long mm_iommu_get(unsigned long ua, unsigned long entries,
23 		struct mm_iommu_table_group_mem_t **pmem);
24 extern long mm_iommu_put(struct mm_iommu_table_group_mem_t *mem);
25 extern void mm_iommu_init(mm_context_t *ctx);
26 extern void mm_iommu_cleanup(mm_context_t *ctx);
27 extern struct mm_iommu_table_group_mem_t *mm_iommu_lookup(unsigned long ua,
28 		unsigned long size);
29 extern struct mm_iommu_table_group_mem_t *mm_iommu_find(unsigned long ua,
30 		unsigned long entries);
31 extern long mm_iommu_ua_to_hpa(struct mm_iommu_table_group_mem_t *mem,
32 		unsigned long ua, unsigned long *hpa);
33 extern long mm_iommu_mapped_inc(struct mm_iommu_table_group_mem_t *mem);
34 extern void mm_iommu_mapped_dec(struct mm_iommu_table_group_mem_t *mem);
35 #endif
36 
37 extern void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next);
38 extern void switch_slb(struct task_struct *tsk, struct mm_struct *mm);
39 extern void set_context(unsigned long id, pgd_t *pgd);
40 
41 #ifdef CONFIG_PPC_BOOK3S_64
42 extern int __init_new_context(void);
43 extern void __destroy_context(int context_id);
44 static inline void mmu_context_init(void) { }
45 #else
46 extern unsigned long __init_new_context(void);
47 extern void __destroy_context(unsigned long context_id);
48 extern void mmu_context_init(void);
49 #endif
50 
51 extern void switch_cop(struct mm_struct *next);
52 extern int use_cop(unsigned long acop, struct mm_struct *mm);
53 extern void drop_cop(unsigned long acop, struct mm_struct *mm);
54 
55 /*
56  * switch_mm is the entry point called from the architecture independent
57  * code in kernel/sched/core.c
58  */
59 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
60 			     struct task_struct *tsk)
61 {
62 	/* Mark this context has been used on the new CPU */
63 	cpumask_set_cpu(smp_processor_id(), mm_cpumask(next));
64 
65 	/* 32-bit keeps track of the current PGDIR in the thread struct */
66 #ifdef CONFIG_PPC32
67 	tsk->thread.pgdir = next->pgd;
68 #endif /* CONFIG_PPC32 */
69 
70 	/* 64-bit Book3E keeps track of current PGD in the PACA */
71 #ifdef CONFIG_PPC_BOOK3E_64
72 	get_paca()->pgd = next->pgd;
73 #endif
74 	/* Nothing else to do if we aren't actually switching */
75 	if (prev == next)
76 		return;
77 
78 #ifdef CONFIG_PPC_ICSWX
79 	/* Switch coprocessor context only if prev or next uses a coprocessor */
80 	if (prev->context.acop || next->context.acop)
81 		switch_cop(next);
82 #endif /* CONFIG_PPC_ICSWX */
83 
84 	/* We must stop all altivec streams before changing the HW
85 	 * context
86 	 */
87 #ifdef CONFIG_ALTIVEC
88 	if (cpu_has_feature(CPU_FTR_ALTIVEC))
89 		asm volatile ("dssall");
90 #endif /* CONFIG_ALTIVEC */
91 
92 	/* The actual HW switching method differs between the various
93 	 * sub architectures.
94 	 */
95 #ifdef CONFIG_PPC_STD_MMU_64
96 	switch_slb(tsk, next);
97 #else
98 	/* Out of line for now */
99 	switch_mmu_context(prev, next);
100 #endif
101 
102 }
103 
104 #define deactivate_mm(tsk,mm)	do { } while (0)
105 
106 /*
107  * After we have set current->mm to a new value, this activates
108  * the context for the new mm so we see the new mappings.
109  */
110 static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
111 {
112 	unsigned long flags;
113 
114 	local_irq_save(flags);
115 	switch_mm(prev, next, current);
116 	local_irq_restore(flags);
117 }
118 
119 /* We don't currently use enter_lazy_tlb() for anything */
120 static inline void enter_lazy_tlb(struct mm_struct *mm,
121 				  struct task_struct *tsk)
122 {
123 	/* 64-bit Book3E keeps track of current PGD in the PACA */
124 #ifdef CONFIG_PPC_BOOK3E_64
125 	get_paca()->pgd = NULL;
126 #endif
127 }
128 
129 static inline void arch_dup_mmap(struct mm_struct *oldmm,
130 				 struct mm_struct *mm)
131 {
132 }
133 
134 static inline void arch_exit_mmap(struct mm_struct *mm)
135 {
136 }
137 
138 static inline void arch_unmap(struct mm_struct *mm,
139 			      struct vm_area_struct *vma,
140 			      unsigned long start, unsigned long end)
141 {
142 	if (start <= mm->context.vdso_base && mm->context.vdso_base < end)
143 		mm->context.vdso_base = 0;
144 }
145 
146 static inline void arch_bprm_mm_init(struct mm_struct *mm,
147 				     struct vm_area_struct *vma)
148 {
149 }
150 
151 #endif /* __KERNEL__ */
152 #endif /* __ASM_POWERPC_MMU_CONTEXT_H */
153