include/asm-um/mmu_context.h

   1 /*
   2  * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #ifndef __UM_MMU_CONTEXT_H
   7 #define __UM_MMU_CONTEXT_H
   8
   9 #include "linux/sched.h"
  10 #include "choose-mode.h"
  11 #include "um_mmu.h"
  12
  13 #define get_mmu_context(task) do ; while(0)
  14 #define activate_context(tsk) do ; while(0)
  15
  16 #define deactivate_mm(tsk,mm)   do { } while (0)
  17
  18 extern void force_flush_all(void);
  19
  20 static inline void activate_mm(struct mm_struct *old, struct mm_struct *new)
  21 {
  22         /*
  23          * This is called by fs/exec.c and fs/aio.c. In the first case, for an
  24          * exec, we don't need to do anything as we're called from userspace
  25          * and thus going to use a new host PID. In the second, we're called
  26          * from a kernel thread, and thus need to go doing the mmap's on the
  27          * host. Since they're very expensive, we want to avoid that as far as
  28          * possible.
  29          */
  30         if (old != new && (current->flags & PF_BORROWED_MM))
  31                 CHOOSE_MODE(force_flush_all(),
  32                             switch_mm_skas(&new->context.skas.id));
  33 }
  34
  35 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
  36                              struct task_struct *tsk)
  37 {
  38         unsigned cpu = smp_processor_id();
  39
  40         if(prev != next){
  41                 cpu_clear(cpu, prev->cpu_vm_mask);
  42                 cpu_set(cpu, next->cpu_vm_mask);
  43                 if(next != &init_mm)
  44                         CHOOSE_MODE((void) 0,
  45                                     switch_mm_skas(&next->context.skas.id));
  46         }
  47 }
  48
  49 static inline void enter_lazy_tlb(struct mm_struct *mm,
  50                                   struct task_struct *tsk)
  51 {
  52 }
  53
  54 extern int init_new_context_skas(struct task_struct *task,
  55                                  struct mm_struct *mm);
  56
  57 static inline int init_new_context_tt(struct task_struct *task,
  58                                       struct mm_struct *mm)
  59 {
  60         return(0);
  61 }
  62
  63 static inline int init_new_context(struct task_struct *task,
  64                                    struct mm_struct *mm)
  65 {
  66         return(CHOOSE_MODE_PROC(init_new_context_tt, init_new_context_skas,
  67                                 task, mm));
  68 }
  69
  70 extern void destroy_context_skas(struct mm_struct *mm);
  71
  72 static inline void destroy_context(struct mm_struct *mm)
  73 {
  74         CHOOSE_MODE((void) 0, destroy_context_skas(mm));
  75 }
  76
  77 #endif
  78
  79 /*
  80  * Overrides for Emacs so that we follow Linus's tabbing style.
  81  * Emacs will notice this stuff at the end of the file and automatically
  82  * adjust the settings for this buffer only.  This must remain at the end
  83  * of the file.
  84  * ---------------------------------------------------------------------------
  85  * Local variables:
  86  * c-file-style: "linux"
  87  * End:
  88  */