arch/um/include/asm/mmu_context.h

   1 /*
   2  * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.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/mm_types.h>
  11
  12 #include <asm/mmu.h>
  13
  14 extern void uml_setup_stubs(struct mm_struct *mm);
  15 /*
  16  * Needed since we do not use the asm-generic/mm_hooks.h:
  17  */
  18 static inline void arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm)
  19 {
  20         uml_setup_stubs(mm);
  21 }
  22 extern void arch_exit_mmap(struct mm_struct *mm);
  23 static inline void arch_unmap(struct mm_struct *mm,
  24                         struct vm_area_struct *vma,
  25                         unsigned long start, unsigned long end)
  26 {
  27 }
  28 static inline void arch_bprm_mm_init(struct mm_struct *mm,
  29                                      struct vm_area_struct *vma)
  30 {
  31 }
  32
  33 static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
  34                 bool write, bool execute, bool foreign)
  35 {
  36         /* by default, allow everything */
  37         return true;
  38 }
  39
  40 static inline bool arch_pte_access_permitted(pte_t pte, bool write)
  41 {
  42         /* by default, allow everything */
  43         return true;
  44 }
  45
  46 /*
  47  * end asm-generic/mm_hooks.h functions
  48  */
  49
  50 #define deactivate_mm(tsk,mm)   do { } while (0)
  51
  52 extern void force_flush_all(void);
  53
  54 static inline void activate_mm(struct mm_struct *old, struct mm_struct *new)
  55 {
  56         /*
  57          * This is called by fs/exec.c and sys_unshare()
  58          * when the new ->mm is used for the first time.
  59          */
  60         __switch_mm(&new->context.id);
  61         down_write(&new->mmap_sem);
  62         uml_setup_stubs(new);
  63         up_write(&new->mmap_sem);
  64 }
  65
  66 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
  67                              struct task_struct *tsk)
  68 {
  69         unsigned cpu = smp_processor_id();
  70
  71         if(prev != next){
  72                 cpumask_clear_cpu(cpu, mm_cpumask(prev));
  73                 cpumask_set_cpu(cpu, mm_cpumask(next));
  74                 if(next != &init_mm)
  75                         __switch_mm(&next->context.id);
  76         }
  77 }
  78
  79 static inline void enter_lazy_tlb(struct mm_struct *mm,
  80                                   struct task_struct *tsk)
  81 {
  82 }
  83
  84 extern int init_new_context(struct task_struct *task, struct mm_struct *mm);
  85
  86 extern void destroy_context(struct mm_struct *mm);
  87
  88 #endif