include/asm-ppc64/mmu_context.h

   1 #ifndef __PPC64_MMU_CONTEXT_H
   2 #define __PPC64_MMU_CONTEXT_H
   3
   4 #include <linux/config.h>
   5 #include <linux/kernel.h>
   6 #include <linux/mm.h>
   7 #include <asm/mmu.h>
   8 #include <asm/cputable.h>
   9
  10 /*
  11  * Copyright (C) 2001 PPC 64 Team, IBM Corp
  12  *
  13  * This program is free software; you can redistribute it and/or
  14  * modify it under the terms of the GNU General Public License
  15  * as published by the Free Software Foundation; either version
  16  * 2 of the License, or (at your option) any later version.
  17  */
  18
  19 static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
  20 {
  21 }
  22
  23 #define NO_CONTEXT      0
  24 #define MAX_CONTEXT     (0x100000-1)
  25
  26 extern int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
  27 extern void destroy_context(struct mm_struct *mm);
  28
  29 extern void switch_stab(struct task_struct *tsk, struct mm_struct *mm);
  30 extern void switch_slb(struct task_struct *tsk, struct mm_struct *mm);
  31
  32 /*
  33  * switch_mm is the entry point called from the architecture independent
  34  * code in kernel/sched.c
  35  */
  36 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
  37                              struct task_struct *tsk)
  38 {
  39         if (!cpu_isset(smp_processor_id(), next->cpu_vm_mask))
  40                 cpu_set(smp_processor_id(), next->cpu_vm_mask);
  41
  42         /* No need to flush userspace segments if the mm doesnt change */
  43         if (prev == next)
  44                 return;
  45
  46 #ifdef CONFIG_ALTIVEC
  47         if (cpu_has_feature(CPU_FTR_ALTIVEC))
  48                 asm volatile ("dssall");
  49 #endif /* CONFIG_ALTIVEC */
  50
  51         if (cpu_has_feature(CPU_FTR_SLB))
  52                 switch_slb(tsk, next);
  53         else
  54                 switch_stab(tsk, next);
  55 }
  56
  57 #define deactivate_mm(tsk,mm)   do { } while (0)
  58
  59 /*
  60  * After we have set current->mm to a new value, this activates
  61  * the context for the new mm so we see the new mappings.
  62  */
  63 static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
  64 {
  65         unsigned long flags;
  66
  67         local_irq_save(flags);
  68         switch_mm(prev, next, current);
  69         local_irq_restore(flags);
  70 }
  71
  72 #endif /* __PPC64_MMU_CONTEXT_H */