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 #if defined(CONFIG_KVM_BOOK3S_HV_POSSIBLE) && defined(CONFIG_PPC_RADIX_MMU)
  71 extern void radix_kvm_prefetch_workaround(struct mm_struct *mm);
  72 #else
  73 static inline void radix_kvm_prefetch_workaround(struct mm_struct *mm) { }
  74 #endif
  75
  76 extern void switch_cop(struct mm_struct *next);
  77 extern int use_cop(unsigned long acop, struct mm_struct *mm);
  78 extern void drop_cop(unsigned long acop, struct mm_struct *mm);
  79
  80 /*
  81  * switch_mm is the entry point called from the architecture independent
  82  * code in kernel/sched/core.c
  83  */
  84 static inline void switch_mm_irqs_off(struct mm_struct *prev,
  85                                       struct mm_struct *next,
  86                                       struct task_struct *tsk)
  87 {
  88         bool new_on_cpu = false;
  89
  90         /* Mark this context has been used on the new CPU */
  91         if (!cpumask_test_cpu(smp_processor_id(), mm_cpumask(next))) {
  92                 cpumask_set_cpu(smp_processor_id(), mm_cpumask(next));
  93                 new_on_cpu = true;
  94         }
  95
  96         /* 32-bit keeps track of the current PGDIR in the thread struct */
  97 #ifdef CONFIG_PPC32
  98         tsk->thread.pgdir = next->pgd;
  99 #endif /* CONFIG_PPC32 */
 100
 101         /* 64-bit Book3E keeps track of current PGD in the PACA */
 102 #ifdef CONFIG_PPC_BOOK3E_64
 103         get_paca()->pgd = next->pgd;
 104 #endif
 105         /* Nothing else to do if we aren't actually switching */
 106         if (prev == next)
 107                 return;
 108
 109 #ifdef CONFIG_PPC_ICSWX
 110         /* Switch coprocessor context only if prev or next uses a coprocessor */
 111         if (prev->context.acop || next->context.acop)
 112                 switch_cop(next);
 113 #endif /* CONFIG_PPC_ICSWX */
 114
 115         /* We must stop all altivec streams before changing the HW
 116          * context
 117          */
 118 #ifdef CONFIG_ALTIVEC
 119         if (cpu_has_feature(CPU_FTR_ALTIVEC))
 120                 asm volatile ("dssall");
 121 #endif /* CONFIG_ALTIVEC */
 122
 123         if (new_on_cpu)
 124                 radix_kvm_prefetch_workaround(next);
 125
 126         /*
 127          * The actual HW switching method differs between the various
 128          * sub architectures. Out of line for now
 129          */
 130         switch_mmu_context(prev, next, tsk);
 131 }
 132
 133 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
 134                              struct task_struct *tsk)
 135 {
 136         unsigned long flags;
 137
 138         local_irq_save(flags);
 139         switch_mm_irqs_off(prev, next, tsk);
 140         local_irq_restore(flags);
 141 }
 142 #define switch_mm_irqs_off switch_mm_irqs_off
 143
 144
 145 #define deactivate_mm(tsk,mm)   do { } while (0)
 146
 147 /*
 148  * After we have set current->mm to a new value, this activates
 149  * the context for the new mm so we see the new mappings.
 150  */
 151 static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
 152 {
 153         unsigned long flags;
 154
 155         local_irq_save(flags);
 156         switch_mm(prev, next, current);
 157         local_irq_restore(flags);
 158 }
 159
 160 /* We don't currently use enter_lazy_tlb() for anything */
 161 static inline void enter_lazy_tlb(struct mm_struct *mm,
 162                                   struct task_struct *tsk)
 163 {
 164         /* 64-bit Book3E keeps track of current PGD in the PACA */
 165 #ifdef CONFIG_PPC_BOOK3E_64
 166         get_paca()->pgd = NULL;
 167 #endif
 168 }
 169
 170 static inline void arch_dup_mmap(struct mm_struct *oldmm,
 171                                  struct mm_struct *mm)
 172 {
 173 }
 174
 175 static inline void arch_exit_mmap(struct mm_struct *mm)
 176 {
 177 }
 178
 179 static inline void arch_unmap(struct mm_struct *mm,
 180                               struct vm_area_struct *vma,
 181                               unsigned long start, unsigned long end)
 182 {
 183         if (start <= mm->context.vdso_base && mm->context.vdso_base < end)
 184                 mm->context.vdso_base = 0;
 185 }
 186
 187 static inline void arch_bprm_mm_init(struct mm_struct *mm,
 188                                      struct vm_area_struct *vma)
 189 {
 190 }
 191
 192 static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
 193                 bool write, bool execute, bool foreign)
 194 {
 195         /* by default, allow everything */
 196         return true;
 197 }
 198 #endif /* __KERNEL__ */
 199 #endif /* __ASM_POWERPC_MMU_CONTEXT_H */