/* SPDX-License-Identifier: GPL-2.0 */

  #ifndef __LINUX_VMACACHE_H
  #define __LINUX_VMACACHE_H
  
  #include <linux/sched.h>
  #include <linux/mm.h>
  
  /*
   * Hash based on the page number. Provides a good hit rate for
   * workloads with good locality and those with random accesses as well.
   */
  #define VMACACHE_HASH(addr) ((addr >> PAGE_SHIFT) & VMACACHE_MASK)
  
  static inline void vmacache_flush(struct task_struct *tsk)
  {

  	memset(tsk->vmacache.vmas, 0, sizeof(tsk->vmacache.vmas));

  }

  extern void vmacache_update(unsigned long addr, struct vm_area_struct *newvma);
  extern struct vm_area_struct *vmacache_find(struct mm_struct *mm,
  						    unsigned long addr);
  
  #ifndef CONFIG_MMU
  extern struct vm_area_struct *vmacache_find_exact(struct mm_struct *mm,
  						  unsigned long start,
  						  unsigned long end);
  #endif
  
  static inline void vmacache_invalidate(struct mm_struct *mm)
  {
  	mm->vmacache_seqnum++;

  }
  
  #endif /* __LINUX_VMACACHE_H */