include/asm-s390/tlbflush.h

   1 #ifndef _S390_TLBFLUSH_H
   2 #define _S390_TLBFLUSH_H
   3
   4 #include <linux/mm.h>
   5 #include <asm/processor.h>
   6 #include <asm/pgalloc.h>
   7
   8 /*
   9  * Flush all tlb entries on the local cpu.
  10  */
  11 static inline void __tlb_flush_local(void)
  12 {
  13         asm volatile("ptlb" : : : "memory");
  14 }
  15
  16 /*
  17  * Flush all tlb entries on all cpus.
  18  */
  19 static inline void __tlb_flush_global(void)
  20 {
  21         extern void smp_ptlb_all(void);
  22         register unsigned long reg2 asm("2");
  23         register unsigned long reg3 asm("3");
  24         register unsigned long reg4 asm("4");
  25         long dummy;
  26
  27 #ifndef __s390x__
  28         if (!MACHINE_HAS_CSP) {
  29                 smp_ptlb_all();
  30                 return;
  31         }
  32 #endif /* __s390x__ */
  33
  34         dummy = 0;
  35         reg2 = reg3 = 0;
  36         reg4 = ((unsigned long) &dummy) + 1;
  37         asm volatile(
  38                 "       csp     %0,%2"
  39                 : : "d" (reg2), "d" (reg3), "d" (reg4), "m" (dummy) : "cc" );
  40 }
  41
  42 /*
  43  * Flush all tlb entries of a page table on all cpus.
  44  */
  45 static inline void __tlb_flush_idte(unsigned long asce)
  46 {
  47         asm volatile(
  48                 "       .insn   rrf,0xb98e0000,0,%0,%1,0"
  49                 : : "a" (2048), "a" (asce) : "cc" );
  50 }
  51
  52 static inline void __tlb_flush_mm(struct mm_struct * mm)
  53 {
  54         cpumask_t local_cpumask;
  55
  56         if (unlikely(cpus_empty(mm->cpu_vm_mask)))
  57                 return;
  58         /*
  59          * If the machine has IDTE we prefer to do a per mm flush
  60          * on all cpus instead of doing a local flush if the mm
  61          * only ran on the local cpu.
  62          */
  63         if (MACHINE_HAS_IDTE) {
  64                 if (mm->context.noexec)
  65                         __tlb_flush_idte((unsigned long)
  66                                          get_shadow_table(mm->pgd) |
  67                                          mm->context.asce_bits);
  68                 __tlb_flush_idte((unsigned long) mm->pgd |
  69                                  mm->context.asce_bits);
  70                 return;
  71         }
  72         preempt_disable();
  73         /*
  74          * If the process only ran on the local cpu, do a local flush.
  75          */
  76         local_cpumask = cpumask_of_cpu(smp_processor_id());
  77         if (cpus_equal(mm->cpu_vm_mask, local_cpumask))
  78                 __tlb_flush_local();
  79         else
  80                 __tlb_flush_global();
  81         preempt_enable();
  82 }
  83
  84 static inline void __tlb_flush_mm_cond(struct mm_struct * mm)
  85 {
  86         if (atomic_read(&mm->mm_users) <= 1 && mm == current->active_mm)
  87                 __tlb_flush_mm(mm);
  88 }
  89
  90 /*
  91  * TLB flushing:
  92  *  flush_tlb() - flushes the current mm struct TLBs
  93  *  flush_tlb_all() - flushes all processes TLBs
  94  *  flush_tlb_mm(mm) - flushes the specified mm context TLB's
  95  *  flush_tlb_page(vma, vmaddr) - flushes one page
  96  *  flush_tlb_range(vma, start, end) - flushes a range of pages
  97  *  flush_tlb_kernel_range(start, end) - flushes a range of kernel pages
  98  */
  99
 100 /*
 101  * flush_tlb_mm goes together with ptep_set_wrprotect for the
 102  * copy_page_range operation and flush_tlb_range is related to
 103  * ptep_get_and_clear for change_protection. ptep_set_wrprotect and
 104  * ptep_get_and_clear do not flush the TLBs directly if the mm has
 105  * only one user. At the end of the update the flush_tlb_mm and
 106  * flush_tlb_range functions need to do the flush.
 107  */
 108 #define flush_tlb()                             do { } while (0)
 109 #define flush_tlb_all()                         do { } while (0)
 110 #define flush_tlb_page(vma, addr)               do { } while (0)
 111
 112 static inline void flush_tlb_mm(struct mm_struct *mm)
 113 {
 114         __tlb_flush_mm_cond(mm);
 115 }
 116
 117 static inline void flush_tlb_range(struct vm_area_struct *vma,
 118                                    unsigned long start, unsigned long end)
 119 {
 120         __tlb_flush_mm_cond(vma->vm_mm);
 121 }
 122
 123 static inline void flush_tlb_kernel_range(unsigned long start,
 124                                           unsigned long end)
 125 {
 126         __tlb_flush_mm(&init_mm);
 127 }
 128
 129 #endif /* _S390_TLBFLUSH_H */