arch/powerpc/include/asm/mmu_context.h

   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 extern void switch_slb(struct task_struct *tsk, struct mm_struct *mm);
  37 extern void set_context(unsigned long id, pgd_t *pgd);
  38
  39 #ifdef CONFIG_PPC_BOOK3S_64
  40 extern void radix__switch_mmu_context(struct mm_struct *prev,
  41                                      struct mm_struct *next);
  42 static inline void switch_mmu_context(struct mm_struct *prev,
  43                                       struct mm_struct *next,
  44                                       struct task_struct *tsk)
  45 {
  46         if (radix_enabled())
  47                 return radix__switch_mmu_context(prev, next);
  48         return switch_slb(tsk, next);
  49 }
  50
  51 extern int __init_new_context(void);
  52 extern void __destroy_context(int context_id);
  53 static inline void mmu_context_init(void) { }
  54 #else
  55 extern void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next,
  56                                struct task_struct *tsk);
  57 extern unsigned long __init_new_context(void);
  58 extern void __destroy_context(unsigned long context_id);
  59 extern void mmu_context_init(void);
  60 #endif
  61
  62 extern void switch_cop(struct mm_struct *next);
  63 extern int use_cop(unsigned long acop, struct mm_struct *mm);
  64 extern void drop_cop(unsigned long acop, struct mm_struct *mm);
  65
  66 /*
  67  * switch_mm is the entry point called from the architecture independent
  68  * code in kernel/sched/core.c
  69  */
  70 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
  71                              struct task_struct *tsk)
  72 {
  73         /* Mark this context has been used on the new CPU */
  74         cpumask_set_cpu(smp_processor_id(), mm_cpumask(next));
  75
  76         /* 32-bit keeps track of the current PGDIR in the thread struct */
  77 #ifdef CONFIG_PPC32
  78         tsk->thread.pgdir = next->pgd;
  79 #endif /* CONFIG_PPC32 */
  80
  81         /* 64-bit Book3E keeps track of current PGD in the PACA */
  82 #ifdef CONFIG_PPC_BOOK3E_64
  83         get_paca()->pgd = next->pgd;
  84 #endif
  85         /* Nothing else to do if we aren't actually switching */
  86         if (prev == next)
  87                 return;
  88
  89 #ifdef CONFIG_PPC_ICSWX
  90         /* Switch coprocessor context only if prev or next uses a coprocessor */
  91         if (prev->context.acop || next->context.acop)
  92                 switch_cop(next);
  93 #endif /* CONFIG_PPC_ICSWX */
  94
  95         /* We must stop all altivec streams before changing the HW
  96          * context
  97          */
  98 #ifdef CONFIG_ALTIVEC
  99         if (cpu_has_feature(CPU_FTR_ALTIVEC))
 100                 asm volatile ("dssall");
 101 #endif /* CONFIG_ALTIVEC */
 102         /*
 103          * The actual HW switching method differs between the various
 104          * sub architectures. Out of line for now
 105          */
 106         switch_mmu_context(prev, next, tsk);
 107 }
 108
 109 #define deactivate_mm(tsk,mm)   do { } while (0)
 110
 111 /*
 112  * After we have set current->mm to a new value, this activates
 113  * the context for the new mm so we see the new mappings.
 114  */
 115 static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
 116 {
 117         unsigned long flags;
 118
 119         local_irq_save(flags);
 120         switch_mm(prev, next, current);
 121         local_irq_restore(flags);
 122 }
 123
 124 /* We don't currently use enter_lazy_tlb() for anything */
 125 static inline void enter_lazy_tlb(struct mm_struct *mm,
 126                                   struct task_struct *tsk)
 127 {
 128         /* 64-bit Book3E keeps track of current PGD in the PACA */
 129 #ifdef CONFIG_PPC_BOOK3E_64
 130         get_paca()->pgd = NULL;
 131 #endif
 132 }
 133
 134 static inline void arch_dup_mmap(struct mm_struct *oldmm,
 135                                  struct mm_struct *mm)
 136 {
 137 }
 138
 139 static inline void arch_exit_mmap(struct mm_struct *mm)
 140 {
 141 }
 142
 143 static inline void arch_unmap(struct mm_struct *mm,
 144                               struct vm_area_struct *vma,
 145                               unsigned long start, unsigned long end)
 146 {
 147         if (start <= mm->context.vdso_base && mm->context.vdso_base < end)
 148                 mm->context.vdso_base = 0;
 149 }
 150
 151 static inline void arch_bprm_mm_init(struct mm_struct *mm,
 152                                      struct vm_area_struct *vma)
 153 {
 154 }
 155
 156 static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
 157                 bool write, bool execute, bool foreign)
 158 {
 159         /* by default, allow everything */
 160         return true;
 161 }
 162
 163 static inline bool arch_pte_access_permitted(pte_t pte, bool write)
 164 {
 165         /* by default, allow everything */
 166         return true;
 167 }
 168 #endif /* __KERNEL__ */
 169 #endif /* __ASM_POWERPC_MMU_CONTEXT_H */