page_table.cc revision 2665 
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 *          Ron Dreslinski
30 */
31
32/**
33 * @file
34 * Definitions of page table.
35 */
36#include <string>
37#include <map>
38#include <fstream>
39
40#include "arch/faults.hh"
41#include "base/bitfield.hh"
42#include "base/intmath.hh"
43#include "base/trace.hh"
44#include "mem/page_table.hh"
45#include "sim/builder.hh"
46#include "sim/sim_object.hh"
47#include "sim/system.hh"
48
49using namespace std;
50using namespace TheISA;
51
52PageTable::PageTable(System *_system, Addr _pageSize)
53    : pageSize(_pageSize), offsetMask(mask(floorLog2(_pageSize))),
54      system(_system)
55{
56    assert(isPowerOf2(pageSize));
57}
58
59PageTable::~PageTable()
60{
61}
62
63Fault
64PageTable::page_check(Addr addr, int size) const
65{
66    if (size < sizeof(uint64_t)) {
67        if (!isPowerOf2(size)) {
68            panic("Invalid request size!\n");
69            return genMachineCheckFault();
70        }
71
72        if ((size - 1) & addr)
73            return genAlignmentFault();
74    }
75    else {
76        if ((addr & (VMPageSize - 1)) + size > VMPageSize) {
77            panic("Invalid request size!\n");
78            return genMachineCheckFault();
79        }
80
81        if ((sizeof(uint64_t) - 1) & addr)
82            return genAlignmentFault();
83    }
84
85    return NoFault;
86}
87
88
89
90
91void
92PageTable::allocate(Addr vaddr, int size)
93{
94    // starting address must be page aligned
95    assert(pageOffset(vaddr) == 0);
96
97    for (; size > 0; size -= pageSize, vaddr += pageSize) {
98        std::map<Addr,Addr>::iterator iter = pTable.find(vaddr);
99
100        if (iter != pTable.end()) {
101            // already mapped
102            fatal("PageTable::allocate: address 0x%x already mapped", vaddr);
103        }
104
105        pTable[vaddr] = system->new_page();
106    }
107}
108
109
110
111bool
112PageTable::translate(Addr vaddr, Addr &paddr)
113{
114    Addr page_addr = pageAlign(vaddr);
115    std::map<Addr,Addr>::iterator iter = pTable.find(page_addr);
116
117    if (iter == pTable.end()) {
118        return false;
119    }
120
121    paddr = iter->second + pageOffset(vaddr);
122    return true;
123}
124
125
126Fault
127PageTable::translate(RequestPtr &req)
128{
129    Addr paddr;
130    assert(pageAlign(req->getVaddr() + req->getSize() - 1)
131           == pageAlign(req->getVaddr()));
132    if (!translate(req->getVaddr(), paddr)) {
133        return genMachineCheckFault();
134    }
135    req->setPaddr(paddr);
136    return page_check(req->getPaddr(), req->getSize());
137}
138