page_table.hh revision 5748:f28f020f3006
1/* 2 * Copyright (c) 2003 The Regents of The University of Michigan 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are 7 * met: redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer; 9 * redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution; 12 * neither the name of the copyright holders nor the names of its 13 * contributors may be used to endorse or promote products derived from 14 * this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 * 28 * Authors: Steve Reinhardt 29 */ 30 31/** 32 * @file 33 * Declaration of a non-full system Page Table. 34 */ 35 36#ifndef __PAGE_TABLE__ 37#define __PAGE_TABLE__ 38 39#include <string> 40 41#include "sim/faults.hh" 42#include "arch/isa_traits.hh" 43#include "arch/tlb.hh" 44#include "base/hashmap.hh" 45#include "mem/request.hh" 46#include "sim/host.hh" 47#include "sim/serialize.hh" 48 49class Process; 50 51/** 52 * Page Table Declaration. 53 */ 54class PageTable 55{ 56 protected: 57 typedef m5::hash_map<Addr, TheISA::TlbEntry> PTable; 58 typedef PTable::iterator PTableItr; 59 PTable pTable; 60 61 struct cacheElement { 62 Addr vaddr; 63 TheISA::TlbEntry entry; 64 }; 65 66 struct cacheElement pTableCache[3]; 67 68 const Addr pageSize; 69 const Addr offsetMask; 70 71 Process *process; 72 73 public: 74 75 PageTable(Process *_process, Addr _pageSize = TheISA::VMPageSize); 76 77 ~PageTable(); 78 79 Addr pageAlign(Addr a) { return (a & ~offsetMask); } 80 Addr pageOffset(Addr a) { return (a & offsetMask); } 81 82 void allocate(Addr vaddr, int64_t size); 83 84 /** 85 * Lookup function 86 * @param vaddr The virtual address. 87 * @return entry The page table entry corresponding to vaddr. 88 */ 89 bool lookup(Addr vaddr, TheISA::TlbEntry &entry); 90 91 /** 92 * Translate function 93 * @param vaddr The virtual address. 94 * @param paddr Physical address from translation. 95 * @return True if translation exists 96 */ 97 bool translate(Addr vaddr, Addr &paddr); 98 99 /** 100 * Simplified translate function (just check for translation) 101 * @param vaddr The virtual address. 102 * @return True if translation exists 103 */ 104 bool translate(Addr vaddr) { Addr dummy; return translate(vaddr, dummy); } 105 106 /** 107 * Perform a translation on the memory request, fills in paddr 108 * field of req. 109 * @param req The memory request. 110 */ 111 Fault translate(RequestPtr req); 112 113 /** 114 * Update the page table cache. 115 * @param vaddr virtual address (page aligned) to check 116 * @param pte page table entry to return 117 */ 118 inline void updateCache(Addr vaddr, TheISA::TlbEntry entry) 119 { 120 pTableCache[2].entry = pTableCache[1].entry; 121 pTableCache[2].vaddr = pTableCache[1].vaddr; 122 pTableCache[1].entry = pTableCache[0].entry; 123 pTableCache[1].vaddr = pTableCache[0].vaddr; 124 pTableCache[0].entry = entry; 125 pTableCache[0].vaddr = vaddr; 126 } 127 128 129 void serialize(std::ostream &os); 130 131 void unserialize(Checkpoint *cp, const std::string §ion); 132}; 133 134#endif 135