text: #ifndef _S390_TLBFLUSH_H
  #define _S390_TLBFLUSH_H
  
  #include <linux/mm.h>
  #include <linux/sched.h>
  #include <asm/processor.h>
  #include <asm/pgalloc.h>
  
  /*
   * Flush all tlb entries on the local cpu.
   */
  static inline void __tlb_flush_local(void)
  {
  	asm volatile("ptlb" : : : "memory");
  }
  
  #ifdef CONFIG_SMP
  /*
   * Flush all tlb entries on all cpus.
   */
  void smp_ptlb_all(void);
  
  static inline void __tlb_flush_global(void)
  {
  	register unsigned long reg2 asm("2");
  	register unsigned long reg3 asm("3");
  	register unsigned long reg4 asm("4");
  	long dummy;
  
  #ifndef __s390x__
  	if (!MACHINE_HAS_CSP) {
  		smp_ptlb_all();
  		return;
  	}
  #endif /* __s390x__ */
  
  	dummy = 0;
  	reg2 = reg3 = 0;
  	reg4 = ((unsigned long) &dummy) + 1;
  	asm volatile(
  		"	csp	%0,%2"
  		: : "d" (reg2), "d" (reg3), "d" (reg4), "m" (dummy) : "cc" );
  }
  
  static inline void __tlb_flush_full(struct mm_struct *mm)
  {
  	cpumask_t local_cpumask;
  
  	preempt_disable();
  	/*
  	 * If the process only ran on the local cpu, do a local flush.
  	 */
  	cpumask_copy(&local_cpumask, cpumask_of(smp_processor_id()));
  	if (cpumask_equal(mm_cpumask(mm), &local_cpumask))
  		__tlb_flush_local();
  	else
  		__tlb_flush_global();
  	preempt_enable();
  }
  #else
  #define __tlb_flush_full(mm)	__tlb_flush_local()
  #endif
  
  /*
   * Flush all tlb entries of a page table on all cpus.
   */
  static inline void __tlb_flush_idte(unsigned long asce)
  {
  	asm volatile(
  		"	.insn	rrf,0xb98e0000,0,%0,%1,0"
  		: : "a" (2048), "a" (asce) : "cc" );
  }
  
  static inline void __tlb_flush_mm(struct mm_struct * mm)
  {
  	if (unlikely(cpumask_empty(mm_cpumask(mm))))
  		return;
  	/*
  	 * If the machine has IDTE we prefer to do a per mm flush
  	 * on all cpus instead of doing a local flush if the mm
  	 * only ran on the local cpu.
  	 */
  	if (MACHINE_HAS_IDTE)
  		__tlb_flush_idte((unsigned long) mm->pgd |
  				 mm->context.asce_bits);
  	else
  		__tlb_flush_full(mm);
  }
  
  static inline void __tlb_flush_mm_cond(struct mm_struct * mm)
  {
  	spin_lock(&mm->page_table_lock);
  	if (mm->context.flush_mm) {
  		__tlb_flush_mm(mm);
  		mm->context.flush_mm = 0;
  	}
  	spin_unlock(&mm->page_table_lock);
  }
  
  /*
   * TLB flushing:
   *  flush_tlb() - flushes the current mm struct TLBs
   *  flush_tlb_all() - flushes all processes TLBs
   *  flush_tlb_mm(mm) - flushes the specified mm context TLB's
   *  flush_tlb_page(vma, vmaddr) - flushes one page
   *  flush_tlb_range(vma, start, end) - flushes a range of pages
   *  flush_tlb_kernel_range(start, end) - flushes a range of kernel pages
   */
  
  /*
   * flush_tlb_mm goes together with ptep_set_wrprotect for the
   * copy_page_range operation and flush_tlb_range is related to
   * ptep_get_and_clear for change_protection. ptep_set_wrprotect and
   * ptep_get_and_clear do not flush the TLBs directly if the mm has
   * only one user. At the end of the update the flush_tlb_mm and
   * flush_tlb_range functions need to do the flush.
   */
  #define flush_tlb()				do { } while (0)
  #define flush_tlb_all()				do { } while (0)
  #define flush_tlb_page(vma, addr)		do { } while (0)
  
  static inline void flush_tlb_mm(struct mm_struct *mm)
  {
  	__tlb_flush_mm_cond(mm);
  }
  
  static inline void flush_tlb_range(struct vm_area_struct *vma,
  				   unsigned long start, unsigned long end)
  {
  	__tlb_flush_mm_cond(vma->vm_mm);
  }
  
  static inline void flush_tlb_kernel_range(unsigned long start,
  					  unsigned long end)
  {
  	__tlb_flush_mm(&init_mm);
  }
  
  #endif /* _S390_TLBFLUSH_H */
  