1/* 2 * This file contains the routines for TLB flushing. 3 * On machines where the MMU uses a hash table to store virtual to 4 * physical translations, these routines flush entries from the 5 * hash table also. 6 * -- paulus 7 * 8 * Derived from arch/ppc/mm/init.c: 9 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) 10 * 11 * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au) 12 * and Cort Dougan (PReP) (cort@cs.nmt.edu) 13 * Copyright (C) 1996 Paul Mackerras 14 * 15 * Derived from "arch/i386/mm/init.c" 16 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds 17 * 18 * This program is free software; you can redistribute it and/or 19 * modify it under the terms of the GNU General Public License 20 * as published by the Free Software Foundation; either version 21 * 2 of the License, or (at your option) any later version. 22 * 23 */ 24 25#include <linux/kernel.h> 26#include <linux/mm.h> 27#include <linux/init.h> 28#include <linux/highmem.h> 29#include <linux/pagemap.h> 30#include <linux/export.h> 31 32#include <asm/tlbflush.h> 33#include <asm/tlb.h> 34 35#include "mmu_decl.h" 36 37/* 38 * Called when unmapping pages to flush entries from the TLB/hash table. 39 */ 40void flush_hash_entry(struct mm_struct *mm, pte_t *ptep, unsigned long addr) 41{ 42 unsigned long ptephys; 43 44 if (Hash != 0) { 45 ptephys = __pa(ptep) & PAGE_MASK; 46 flush_hash_pages(mm->context.id, addr, ptephys, 1); 47 } 48} 49EXPORT_SYMBOL(flush_hash_entry); 50 51/* 52 * Called by ptep_set_access_flags, must flush on CPUs for which the 53 * DSI handler can't just "fixup" the TLB on a write fault 54 */ 55void flush_tlb_page_nohash(struct vm_area_struct *vma, unsigned long addr) 56{ 57 if (Hash != 0) 58 return; 59 _tlbie(addr); 60} 61 62/* 63 * Called at the end of a mmu_gather operation to make sure the 64 * TLB flush is completely done. 65 */ 66void tlb_flush(struct mmu_gather *tlb) 67{ 68 if (Hash == 0) { 69 /* 70 * 603 needs to flush the whole TLB here since 71 * it doesn't use a hash table. 72 */ 73 _tlbia(); 74 } 75} 76 77/* 78 * TLB flushing: 79 * 80 * - flush_tlb_mm(mm) flushes the specified mm context TLB's 81 * - flush_tlb_page(vma, vmaddr) flushes one page 82 * - flush_tlb_range(vma, start, end) flushes a range of pages 83 * - flush_tlb_kernel_range(start, end) flushes kernel pages 84 * 85 * since the hardware hash table functions as an extension of the 86 * tlb as far as the linux tables are concerned, flush it too. 87 * -- Cort 88 */ 89 90static void flush_range(struct mm_struct *mm, unsigned long start, 91 unsigned long end) 92{ 93 pmd_t *pmd; 94 unsigned long pmd_end; 95 int count; 96 unsigned int ctx = mm->context.id; 97 98 if (Hash == 0) { 99 _tlbia(); 100 return; 101 } 102 start &= PAGE_MASK; 103 if (start >= end) 104 return; 105 end = (end - 1) | ~PAGE_MASK; 106 pmd = pmd_offset(pud_offset(pgd_offset(mm, start), start), start); 107 for (;;) { 108 pmd_end = ((start + PGDIR_SIZE) & PGDIR_MASK) - 1; 109 if (pmd_end > end) 110 pmd_end = end; 111 if (!pmd_none(*pmd)) { 112 count = ((pmd_end - start) >> PAGE_SHIFT) + 1; 113 flush_hash_pages(ctx, start, pmd_val(*pmd), count); 114 } 115 if (pmd_end == end) 116 break; 117 start = pmd_end + 1; 118 ++pmd; 119 } 120} 121 122/* 123 * Flush kernel TLB entries in the given range 124 */ 125void flush_tlb_kernel_range(unsigned long start, unsigned long end) 126{ 127 flush_range(&init_mm, start, end); 128} 129EXPORT_SYMBOL(flush_tlb_kernel_range); 130 131/* 132 * Flush all the (user) entries for the address space described by mm. 133 */ 134void flush_tlb_mm(struct mm_struct *mm) 135{ 136 struct vm_area_struct *mp; 137 138 if (Hash == 0) { 139 _tlbia(); 140 return; 141 } 142 143 /* 144 * It is safe to go down the mm's list of vmas when called 145 * from dup_mmap, holding mmap_sem. It would also be safe from 146 * unmap_region or exit_mmap, but not from vmtruncate on SMP - 147 * but it seems dup_mmap is the only SMP case which gets here. 148 */ 149 for (mp = mm->mmap; mp != NULL; mp = mp->vm_next) 150 flush_range(mp->vm_mm, mp->vm_start, mp->vm_end); 151} 152EXPORT_SYMBOL(flush_tlb_mm); 153 154void flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr) 155{ 156 struct mm_struct *mm; 157 pmd_t *pmd; 158 159 if (Hash == 0) { 160 _tlbie(vmaddr); 161 return; 162 } 163 mm = (vmaddr < TASK_SIZE)? vma->vm_mm: &init_mm; 164 pmd = pmd_offset(pud_offset(pgd_offset(mm, vmaddr), vmaddr), vmaddr); 165 if (!pmd_none(*pmd)) 166 flush_hash_pages(mm->context.id, vmaddr, pmd_val(*pmd), 1); 167} 168EXPORT_SYMBOL(flush_tlb_page); 169 170/* 171 * For each address in the range, find the pte for the address 172 * and check _PAGE_HASHPTE bit; if it is set, find and destroy 173 * the corresponding HPTE. 174 */ 175void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, 176 unsigned long end) 177{ 178 flush_range(vma->vm_mm, start, end); 179} 180EXPORT_SYMBOL(flush_tlb_range); 181 182void __init early_init_mmu(void) 183{ 184} 185