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 * Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk). 15 * 16 * Derived from "arch/i386/mm/init.c" 17 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds 18 * 19 * This program is free software; you can redistribute it and/or 20 * modify it under the terms of the GNU General Public License 21 * as published by the Free Software Foundation; either version 22 * 2 of the License, or (at your option) any later version. 23 * 24 */ 25 26#include <linux/kernel.h> 27#include <linux/mm.h> 28#include <linux/init.h> 29#include <linux/highmem.h> 30#include <asm/tlbflush.h> 31#include <asm/tlb.h> 32 33#include "mmu_decl.h" 34 35/* 36 * Called when unmapping pages to flush entries from the TLB/hash table. 37 */ 38void flush_hash_entry(struct mm_struct *mm, pte_t *ptep, unsigned long addr) 39{ 40 unsigned long ptephys; 41 42 if (Hash != 0) { 43 ptephys = __pa(ptep) & PAGE_MASK; 44 flush_hash_pages(mm->context.id, addr, ptephys, 1); 45 } 46} 47 48/* 49 * Called by ptep_set_access_flags, must flush on CPUs for which the 50 * DSI handler can't just "fixup" the TLB on a write fault 51 */ 52void flush_tlb_page_nohash(struct vm_area_struct *vma, unsigned long addr) 53{ 54 if (Hash != 0) 55 return; 56 _tlbie(addr); 57} 58 59/* 60 * Called at the end of a mmu_gather operation to make sure the 61 * TLB flush is completely done. 62 */ 63void tlb_flush(struct mmu_gather *tlb) 64{ 65 if (Hash == 0) { 66 /* 67 * 603 needs to flush the whole TLB here since 68 * it doesn't use a hash table. 69 */ 70 _tlbia(); 71 } 72} 73 74/* 75 * TLB flushing: 76 * 77 * - flush_tlb_mm(mm) flushes the specified mm context TLB's 78 * - flush_tlb_page(vma, vmaddr) flushes one page 79 * - flush_tlb_range(vma, start, end) flushes a range of pages 80 * - flush_tlb_kernel_range(start, end) flushes kernel pages 81 * 82 * since the hardware hash table functions as an extension of the 83 * tlb as far as the linux tables are concerned, flush it too. 84 * -- Cort 85 */ 86 87/* 88 * 750 SMP is a Bad Idea because the 750 doesn't broadcast all 89 * the cache operations on the bus. Hence we need to use an IPI 90 * to get the other CPU(s) to invalidate their TLBs. 91 */ 92#ifdef CONFIG_SMP_750 93#define FINISH_FLUSH smp_send_tlb_invalidate(0) 94#else 95#define FINISH_FLUSH do { } while (0) 96#endif 97 98static void flush_range(struct mm_struct *mm, unsigned long start, 99 unsigned long end) 100{ 101 pmd_t *pmd; 102 unsigned long pmd_end; 103 int count; 104 unsigned int ctx = mm->context.id; 105 106 if (Hash == 0) { 107 _tlbia(); 108 return; 109 } 110 start &= PAGE_MASK; 111 if (start >= end) 112 return; 113 end = (end - 1) | ~PAGE_MASK; 114 pmd = pmd_offset(pud_offset(pgd_offset(mm, start), start), start); 115 for (;;) { 116 pmd_end = ((start + PGDIR_SIZE) & PGDIR_MASK) - 1; 117 if (pmd_end > end) 118 pmd_end = end; 119 if (!pmd_none(*pmd)) { 120 count = ((pmd_end - start) >> PAGE_SHIFT) + 1; 121 flush_hash_pages(ctx, start, pmd_val(*pmd), count); 122 } 123 if (pmd_end == end) 124 break; 125 start = pmd_end + 1; 126 ++pmd; 127 } 128} 129 130/* 131 * Flush kernel TLB entries in the given range 132 */ 133void flush_tlb_kernel_range(unsigned long start, unsigned long end) 134{ 135 flush_range(&init_mm, start, end); 136 FINISH_FLUSH; 137} 138 139/* 140 * Flush all the (user) entries for the address space described by mm. 141 */ 142void flush_tlb_mm(struct mm_struct *mm) 143{ 144 struct vm_area_struct *mp; 145 146 if (Hash == 0) { 147 _tlbia(); 148 return; 149 } 150 151 /* 152 * It is safe to go down the mm's list of vmas when called 153 * from dup_mmap, holding mmap_sem. It would also be safe from 154 * unmap_region or exit_mmap, but not from vmtruncate on SMP - 155 * but it seems dup_mmap is the only SMP case which gets here. 156 */ 157 for (mp = mm->mmap; mp != NULL; mp = mp->vm_next) 158 flush_range(mp->vm_mm, mp->vm_start, mp->vm_end); 159 FINISH_FLUSH; 160} 161 162void flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr) 163{ 164 struct mm_struct *mm; 165 pmd_t *pmd; 166 167 if (Hash == 0) { 168 _tlbie(vmaddr); 169 return; 170 } 171 mm = (vmaddr < TASK_SIZE)? vma->vm_mm: &init_mm; 172 pmd = pmd_offset(pud_offset(pgd_offset(mm, vmaddr), vmaddr), vmaddr); 173 if (!pmd_none(*pmd)) 174 flush_hash_pages(mm->context.id, vmaddr, pmd_val(*pmd), 1); 175 FINISH_FLUSH; 176} 177 178/* 179 * For each address in the range, find the pte for the address 180 * and check _PAGE_HASHPTE bit; if it is set, find and destroy 181 * the corresponding HPTE. 182 */ 183void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, 184 unsigned long end) 185{ 186 flush_range(vma->vm_mm, start, end); 187 FINISH_FLUSH; 188} 189