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 "linux/config.h"
  11 #include "choose-mode.h"
  12 #include "um_mmu.h"
  13
  14 #define get_mmu_context(task) do ; while(0)
  15 #define activate_context(tsk) do ; while(0)
  16
  17 #define deactivate_mm(tsk,mm)   do { } while (0)
  18
  19 extern void force_flush_all(void);
  20
  21 static inline void activate_mm(struct mm_struct *old, struct mm_struct *new)
  22 {
  23         /*
  24          * This is called by fs/exec.c and fs/aio.c. In the first case, for an
  25          * exec, we don't need to do anything as we're called from userspace
  26          * and thus going to use a new host PID. In the second, we're called
  27          * from a kernel thread, and thus need to go doing the mmap's on the
  28          * host. Since they're very expensive, we want to avoid that as far as
  29          * possible.
  30          */
  31         if (old != new && (current->flags & PF_BORROWED_MM))
  32                 CHOOSE_MODE(force_flush_all(),
  33                             switch_mm_skas(&new->context.skas.id));
  34 }
  35
  36 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
  37                              struct task_struct *tsk)
  38 {
  39         unsigned cpu = smp_processor_id();
  40
  41         if(prev != next){
  42                 cpu_clear(cpu, prev->cpu_vm_mask);
  43                 cpu_set(cpu, next->cpu_vm_mask);
  44                 if(next != &init_mm)
  45                         CHOOSE_MODE((void) 0,
  46                                     switch_mm_skas(&next->context.skas.id));
  47         }
  48 }
  49
  50 static inline void enter_lazy_tlb(struct mm_struct *mm,
  51                                   struct task_struct *tsk)
  52 {
  53 }
  54
  55 extern int init_new_context_skas(struct task_struct *task,
  56                                  struct mm_struct *mm);
  57
  58 static inline int init_new_context_tt(struct task_struct *task,
  59                                       struct mm_struct *mm)
  60 {
  61         return(0);
  62 }
  63
  64 static inline int init_new_context(struct task_struct *task,
  65                                    struct mm_struct *mm)
  66 {
  67         return(CHOOSE_MODE_PROC(init_new_context_tt, init_new_context_skas,
  68                                 task, mm));
  69 }
  70
  71 extern void destroy_context_skas(struct mm_struct *mm);
  72
  73 static inline void destroy_context(struct mm_struct *mm)
  74 {
  75         CHOOSE_MODE((void) 0, destroy_context_skas(mm));
  76 }
  77
  78 #endif
  79
  80 /*
  81  * Overrides for Emacs so that we follow Linus's tabbing style.
  82  * Emacs will notice this stuff at the end of the file and automatically
  83  * adjust the settings for this buffer only.  This must remain at the end
  84  * of the file.
  85  * ---------------------------------------------------------------------------
  86  * Local variables:
  87  * c-file-style: "linux"
  88  * End:
  89  */