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 <asm-generic/mm_hooks.h>
  10
  11 #include "linux/sched.h"
  12 #include "choose-mode.h"
  13 #include "um_mmu.h"
  14
  15 #define get_mmu_context(task) do ; while(0)
  16 #define activate_context(tsk) do ; while(0)
  17
  18 #define deactivate_mm(tsk,mm)   do { } while (0)
  19
  20 extern void force_flush_all(void);
  21
  22 static inline void activate_mm(struct mm_struct *old, struct mm_struct *new)
  23 {
  24         /*
  25          * This is called by fs/exec.c and fs/aio.c. In the first case, for an
  26          * exec, we don't need to do anything as we're called from userspace
  27          * and thus going to use a new host PID. In the second, we're called
  28          * from a kernel thread, and thus need to go doing the mmap's on the
  29          * host. Since they're very expensive, we want to avoid that as far as
  30          * possible.
  31          */
  32         if (old != new && (current->flags & PF_BORROWED_MM))
  33                 CHOOSE_MODE(force_flush_all(),
  34                             switch_mm_skas(&new->context.skas.id));
  35 }
  36
  37 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
  38                              struct task_struct *tsk)
  39 {
  40         unsigned cpu = smp_processor_id();
  41
  42         if(prev != next){
  43                 cpu_clear(cpu, prev->cpu_vm_mask);
  44                 cpu_set(cpu, next->cpu_vm_mask);
  45                 if(next != &init_mm)
  46                         CHOOSE_MODE((void) 0,
  47                                     switch_mm_skas(&next->context.skas.id));
  48         }
  49 }
  50
  51 static inline void enter_lazy_tlb(struct mm_struct *mm,
  52                                   struct task_struct *tsk)
  53 {
  54 }
  55
  56 extern int init_new_context_skas(struct task_struct *task,
  57                                  struct mm_struct *mm);
  58
  59 static inline int init_new_context_tt(struct task_struct *task,
  60                                       struct mm_struct *mm)
  61 {
  62         return(0);
  63 }
  64
  65 static inline int init_new_context(struct task_struct *task,
  66                                    struct mm_struct *mm)
  67 {
  68         return(CHOOSE_MODE_PROC(init_new_context_tt, init_new_context_skas,
  69                                 task, mm));
  70 }
  71
  72 extern void destroy_context_skas(struct mm_struct *mm);
  73
  74 static inline void destroy_context(struct mm_struct *mm)
  75 {
  76         CHOOSE_MODE((void) 0, destroy_context_skas(mm));
  77 }
  78
  79 #endif
  80
  81 /*
  82  * Overrides for Emacs so that we follow Linus's tabbing style.
  83  * Emacs will notice this stuff at the end of the file and automatically
  84  * adjust the settings for this buffer only.  This must remain at the end
  85  * of the file.
  86  * ---------------------------------------------------------------------------
  87  * Local variables:
  88  * c-file-style: "linux"
  89  * End:
  90  */