arch/um/include/asm/mmu_context.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
   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 #include <linux/mmap_lock.h>
  12
  13 #include <asm/mmu.h>
  14
  15 extern void uml_setup_stubs(struct mm_struct *mm);
  16 /*
  17  * Needed since we do not use the asm-generic/mm_hooks.h:
  18  */
  19 static inline int arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm)
  20 {
  21         uml_setup_stubs(mm);
  22         return 0;
  23 }
  24 extern void arch_exit_mmap(struct mm_struct *mm);
  25 static inline void arch_unmap(struct mm_struct *mm,
  26                         unsigned long start, unsigned long end)
  27 {
  28 }
  29 static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
  30                 bool write, bool execute, bool foreign)
  31 {
  32         /* by default, allow everything */
  33         return true;
  34 }
  35
  36 /*
  37  * end asm-generic/mm_hooks.h functions
  38  */
  39
  40 #define deactivate_mm(tsk,mm)   do { } while (0)
  41
  42 extern void force_flush_all(void);
  43
  44 static inline void activate_mm(struct mm_struct *old, struct mm_struct *new)
  45 {
  46         /*
  47          * This is called by fs/exec.c and sys_unshare()
  48          * when the new ->mm is used for the first time.
  49          */
  50         __switch_mm(&new->context.id);
  51         mmap_write_lock_nested(new, SINGLE_DEPTH_NESTING);
  52         uml_setup_stubs(new);
  53         mmap_write_unlock(new);
  54 }
  55
  56 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
  57                              struct task_struct *tsk)
  58 {
  59         unsigned cpu = smp_processor_id();
  60
  61         if(prev != next){
  62                 cpumask_clear_cpu(cpu, mm_cpumask(prev));
  63                 cpumask_set_cpu(cpu, mm_cpumask(next));
  64                 if(next != &init_mm)
  65                         __switch_mm(&next->context.id);
  66         }
  67 }
  68
  69 static inline void enter_lazy_tlb(struct mm_struct *mm,
  70                                   struct task_struct *tsk)
  71 {
  72 }
  73
  74 extern int init_new_context(struct task_struct *task, struct mm_struct *mm);
  75
  76 extern void destroy_context(struct mm_struct *mm);
  77
  78 #endif