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 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 */