arch/arm64/include/asm/tlb.h

   1 /*
   2  * Based on arch/arm/include/asm/tlb.h
   3  *
   4  * Copyright (C) 2002 Russell King
   5  * Copyright (C) 2012 ARM Ltd.
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19 #ifndef __ASM_TLB_H
  20 #define __ASM_TLB_H
  21
  22 #define  __tlb_remove_pmd_tlb_entry __tlb_remove_pmd_tlb_entry
  23
  24 #include <asm-generic/tlb.h>
  25
  26 /*
  27  * There's three ways the TLB shootdown code is used:
  28  *  1. Unmapping a range of vmas.  See zap_page_range(), unmap_region().
  29  *     tlb->fullmm = 0, and tlb_start_vma/tlb_end_vma will be called.
  30  *  2. Unmapping all vmas.  See exit_mmap().
  31  *     tlb->fullmm = 1, and tlb_start_vma/tlb_end_vma will be called.
  32  *     Page tables will be freed.
  33  *  3. Unmapping argument pages.  See shift_arg_pages().
  34  *     tlb->fullmm = 0, but tlb_start_vma/tlb_end_vma will not be called.
  35  */
  36 static inline void tlb_flush(struct mmu_gather *tlb)
  37 {
  38         if (tlb->fullmm) {
  39                 flush_tlb_mm(tlb->mm);
  40         } else if (tlb->end > 0) {
  41                 struct vm_area_struct vma = { .vm_mm = tlb->mm, };
  42                 flush_tlb_range(&vma, tlb->start, tlb->end);
  43                 tlb->start = TASK_SIZE;
  44                 tlb->end = 0;
  45         }
  46 }
  47
  48 static inline void tlb_add_flush(struct mmu_gather *tlb, unsigned long addr)
  49 {
  50         if (!tlb->fullmm) {
  51                 tlb->start = min(tlb->start, addr);
  52                 tlb->end = max(tlb->end, addr + PAGE_SIZE);
  53         }
  54 }
  55
  56 /*
  57  * Memorize the range for the TLB flush.
  58  */
  59 static inline void __tlb_remove_tlb_entry(struct mmu_gather *tlb, pte_t *ptep,
  60                                           unsigned long addr)
  61 {
  62         tlb_add_flush(tlb, addr);
  63 }
  64
  65 /*
  66  * In the case of tlb vma handling, we can optimise these away in the
  67  * case where we're doing a full MM flush.  When we're doing a munmap,
  68  * the vmas are adjusted to only cover the region to be torn down.
  69  */
  70 static inline void tlb_start_vma(struct mmu_gather *tlb,
  71                                  struct vm_area_struct *vma)
  72 {
  73         if (!tlb->fullmm) {
  74                 tlb->start = TASK_SIZE;
  75                 tlb->end = 0;
  76         }
  77 }
  78
  79 static inline void tlb_end_vma(struct mmu_gather *tlb,
  80                                struct vm_area_struct *vma)
  81 {
  82         if (!tlb->fullmm)
  83                 tlb_flush(tlb);
  84 }
  85
  86 static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pte,
  87                                   unsigned long addr)
  88 {
  89         pgtable_page_dtor(pte);
  90         tlb_add_flush(tlb, addr);
  91         tlb_remove_page(tlb, pte);
  92 }
  93
  94 #if CONFIG_ARM64_PGTABLE_LEVELS > 2
  95 static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmdp,
  96                                   unsigned long addr)
  97 {
  98         tlb_add_flush(tlb, addr);
  99         tlb_remove_page(tlb, virt_to_page(pmdp));
 100 }
 101 #endif
 102
 103 #if CONFIG_ARM64_PGTABLE_LEVELS > 3
 104 static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pudp,
 105                                   unsigned long addr)
 106 {
 107         tlb_add_flush(tlb, addr);
 108         tlb_remove_page(tlb, virt_to_page(pudp));
 109 }
 110 #endif
 111
 112 static inline void __tlb_remove_pmd_tlb_entry(struct mmu_gather *tlb, pmd_t *pmdp,
 113                                                 unsigned long address)
 114 {
 115         tlb_add_flush(tlb, address);
 116 }
 117
 118 #endif