arch/s390/include/asm/tlbflush.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _S390_TLBFLUSH_H
   3 #define _S390_TLBFLUSH_H
   4
   5 #include <linux/mm.h>
   6 #include <linux/sched.h>
   7 #include <asm/processor.h>
   8
   9 /*
  10  * Flush all TLB entries on the local CPU.
  11  */
  12 static inline void __tlb_flush_local(void)
  13 {
  14         asm volatile("ptlb" : : : "memory");
  15 }
  16
  17 /*
  18  * Flush TLB entries for a specific ASCE on all CPUs
  19  */
  20 static inline void __tlb_flush_idte(unsigned long asce)
  21 {
  22         unsigned long opt;
  23
  24         opt = IDTE_PTOA;
  25         if (MACHINE_HAS_TLB_GUEST)
  26                 opt |= IDTE_GUEST_ASCE;
  27         /* Global TLB flush for the mm */
  28         asm volatile(
  29                 "       .insn   rrf,0xb98e0000,0,%0,%1,0"
  30                 : : "a" (opt), "a" (asce) : "cc");
  31 }
  32
  33 /*
  34  * Flush all TLB entries on all CPUs.
  35  */
  36 static inline void __tlb_flush_global(void)
  37 {
  38         unsigned int dummy = 0;
  39
  40         csp(&dummy, 0, 0);
  41 }
  42
  43 /*
  44  * Flush TLB entries for a specific mm on all CPUs (in case gmap is used
  45  * this implicates multiple ASCEs!).
  46  */
  47 static inline void __tlb_flush_mm(struct mm_struct *mm)
  48 {
  49         unsigned long gmap_asce;
  50
  51         /*
  52          * If the machine has IDTE we prefer to do a per mm flush
  53          * on all cpus instead of doing a local flush if the mm
  54          * only ran on the local cpu.
  55          */
  56         preempt_disable();
  57         atomic_inc(&mm->context.flush_count);
  58         /* Reset TLB flush mask */
  59         cpumask_copy(mm_cpumask(mm), &mm->context.cpu_attach_mask);
  60         barrier();
  61         gmap_asce = READ_ONCE(mm->context.gmap_asce);
  62         if (MACHINE_HAS_IDTE && gmap_asce != -1UL) {
  63                 if (gmap_asce)
  64                         __tlb_flush_idte(gmap_asce);
  65                 __tlb_flush_idte(mm->context.asce);
  66         } else {
  67                 /* Global TLB flush */
  68                 __tlb_flush_global();
  69         }
  70         atomic_dec(&mm->context.flush_count);
  71         preempt_enable();
  72 }
  73
  74 static inline void __tlb_flush_kernel(void)
  75 {
  76         if (MACHINE_HAS_IDTE)
  77                 __tlb_flush_idte(init_mm.context.asce);
  78         else
  79                 __tlb_flush_global();
  80 }
  81
  82 static inline void __tlb_flush_mm_lazy(struct mm_struct * mm)
  83 {
  84         spin_lock(&mm->context.lock);
  85         if (mm->context.flush_mm) {
  86                 mm->context.flush_mm = 0;
  87                 __tlb_flush_mm(mm);
  88         }
  89         spin_unlock(&mm->context.lock);
  90 }
  91
  92 /*
  93  * TLB flushing:
  94  *  flush_tlb() - flushes the current mm struct TLBs
  95  *  flush_tlb_all() - flushes all processes TLBs
  96  *  flush_tlb_mm(mm) - flushes the specified mm context TLB's
  97  *  flush_tlb_page(vma, vmaddr) - flushes one page
  98  *  flush_tlb_range(vma, start, end) - flushes a range of pages
  99  *  flush_tlb_kernel_range(start, end) - flushes a range of kernel pages
 100  */
 101
 102 /*
 103  * flush_tlb_mm goes together with ptep_set_wrprotect for the
 104  * copy_page_range operation and flush_tlb_range is related to
 105  * ptep_get_and_clear for change_protection. ptep_set_wrprotect and
 106  * ptep_get_and_clear do not flush the TLBs directly if the mm has
 107  * only one user. At the end of the update the flush_tlb_mm and
 108  * flush_tlb_range functions need to do the flush.
 109  */
 110 #define flush_tlb()                             do { } while (0)
 111 #define flush_tlb_all()                         do { } while (0)
 112 #define flush_tlb_page(vma, addr)               do { } while (0)
 113
 114 static inline void flush_tlb_mm(struct mm_struct *mm)
 115 {
 116         __tlb_flush_mm_lazy(mm);
 117 }
 118
 119 static inline void flush_tlb_range(struct vm_area_struct *vma,
 120                                    unsigned long start, unsigned long end)
 121 {
 122         __tlb_flush_mm_lazy(vma->vm_mm);
 123 }
 124
 125 static inline void flush_tlb_kernel_range(unsigned long start,
 126                                           unsigned long end)
 127 {
 128         __tlb_flush_kernel();
 129 }
 130
 131 #endif /* _S390_TLBFLUSH_H */