LXR linux/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 */
  12static 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 */
  20static 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 */
  36static 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 */
  47static 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
  74static 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
  82static 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
 114static inline void flush_tlb_mm(struct mm_struct *mm)
 115{
 116        __tlb_flush_mm_lazy(mm);
 117}
 118
 119static 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
 125static 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 */
 132