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
  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 int arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm)
  19 {
  20         uml_setup_stubs(mm);
  21         return 0;
  22 }
  23 extern void arch_exit_mmap(struct mm_struct *mm);
  24 static inline void arch_unmap(struct mm_struct *mm,
  25                         unsigned long start, unsigned long end)
  26 {
  27 }
  28 static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
  29                 bool write, bool execute, bool foreign)
  30 {
  31         /* by default, allow everything */
  32         return true;
  33 }
  34
  35 /*
  36  * end asm-generic/mm_hooks.h functions
  37  */
  38
  39 #define deactivate_mm(tsk,mm)   do { } while (0)
  40
  41 extern void force_flush_all(void);
  42
  43 static inline void activate_mm(struct mm_struct *old, struct mm_struct *new)
  44 {
  45         /*
  46          * This is called by fs/exec.c and sys_unshare()
  47          * when the new ->mm is used for the first time.
  48          */
  49         __switch_mm(&new->context.id);
  50         down_write_nested(&new->mmap_sem, 1);
  51         uml_setup_stubs(new);
  52         up_write(&new->mmap_sem);
  53 }
  54
  55 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
  56                              struct task_struct *tsk)
  57 {
  58         unsigned cpu = smp_processor_id();
  59
  60         if(prev != next){
  61                 cpumask_clear_cpu(cpu, mm_cpumask(prev));
  62                 cpumask_set_cpu(cpu, mm_cpumask(next));
  63                 if(next != &init_mm)
  64                         __switch_mm(&next->context.id);
  65         }
  66 }
  67
  68 static inline void enter_lazy_tlb(struct mm_struct *mm,
  69                                   struct task_struct *tsk)
  70 {
  71 }
  72
  73 extern int init_new_context(struct task_struct *task, struct mm_struct *mm);
  74
  75 extern void destroy_context(struct mm_struct *mm);
  76
  77 #endif