include/asm-x86/mmu_context_64.h

   1 #ifndef __X86_64_MMU_CONTEXT_H
   2 #define __X86_64_MMU_CONTEXT_H
   3
   4 #include <asm/desc.h>
   5 #include <asm/atomic.h>
   6 #include <asm/pgalloc.h>
   7 #include <asm/pda.h>
   8 #include <asm/pgtable.h>
   9 #include <asm/tlbflush.h>
  10 #ifndef CONFIG_PARAVIRT
  11 #include <asm-generic/mm_hooks.h>
  12 #endif
  13
  14 /*
  15  * possibly do the LDT unload here?
  16  */
  17 int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
  18 void destroy_context(struct mm_struct *mm);
  19
  20 static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
  21 {
  22 #ifdef CONFIG_SMP
  23         if (read_pda(mmu_state) == TLBSTATE_OK)
  24                 write_pda(mmu_state, TLBSTATE_LAZY);
  25 #endif
  26 }
  27
  28 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
  29                              struct task_struct *tsk)
  30 {
  31         unsigned cpu = smp_processor_id();
  32         if (likely(prev != next)) {
  33                 /* stop flush ipis for the previous mm */
  34                 cpu_clear(cpu, prev->cpu_vm_mask);
  35 #ifdef CONFIG_SMP
  36                 write_pda(mmu_state, TLBSTATE_OK);
  37                 write_pda(active_mm, next);
  38 #endif
  39                 cpu_set(cpu, next->cpu_vm_mask);
  40                 load_cr3(next->pgd);
  41
  42                 if (unlikely(next->context.ldt != prev->context.ldt))
  43                         load_LDT_nolock(&next->context);
  44         }
  45 #ifdef CONFIG_SMP
  46         else {
  47                 write_pda(mmu_state, TLBSTATE_OK);
  48                 if (read_pda(active_mm) != next)
  49                         BUG();
  50                 if (!cpu_test_and_set(cpu, next->cpu_vm_mask)) {
  51                         /* We were in lazy tlb mode and leave_mm disabled
  52                          * tlb flush IPI delivery. We must reload CR3
  53                          * to make sure to use no freed page tables.
  54                          */
  55                         load_cr3(next->pgd);
  56                         load_LDT_nolock(&next->context);
  57                 }
  58         }
  59 #endif
  60 }
  61
  62 #define deactivate_mm(tsk, mm)                  \
  63 do {                                            \
  64         load_gs_index(0);                       \
  65         asm volatile("movl %0,%%fs"::"r"(0));   \
  66 } while (0)
  67
  68 #define activate_mm(prev, next)                 \
  69         switch_mm((prev), (next), NULL)
  70
  71
  72 #endif