page_table.cc revision 2632:1bb2f91485ea 
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
29/**
30 * @file
31 * Definitions of page table.
32 */
33#include <string>
34#include <map>
35#include <fstream>
36
37#include "arch/faults.hh"
38#include "base/bitfield.hh"
39#include "base/intmath.hh"
40#include "base/trace.hh"
41#include "mem/page_table.hh"
42#include "sim/builder.hh"
43#include "sim/sim_object.hh"
44#include "sim/system.hh"
45
46using namespace std;
47using namespace TheISA;
48
49PageTable::PageTable(System *_system, Addr _pageSize)
50    : pageSize(_pageSize), offsetMask(mask(floorLog2(_pageSize))),
51      system(_system)
52{
53    assert(isPowerOf2(pageSize));
54}
55
56PageTable::~PageTable()
57{
58}
59
60Fault
61PageTable::page_check(Addr addr, int size) const
62{
63    if (size < sizeof(uint64_t)) {
64        if (!isPowerOf2(size)) {
65            panic("Invalid request size!\n");
66            return genMachineCheckFault();
67        }
68
69        if ((size - 1) & addr)
70            return genAlignmentFault();
71    }
72    else {
73        if ((addr & (VMPageSize - 1)) + size > VMPageSize) {
74            panic("Invalid request size!\n");
75            return genMachineCheckFault();
76        }
77
78        if ((sizeof(uint64_t) - 1) & addr)
79            return genAlignmentFault();
80    }
81
82    return NoFault;
83}
84
85
86
87
88void
89PageTable::allocate(Addr vaddr, int size)
90{
91    // starting address must be page aligned
92    assert(pageOffset(vaddr) == 0);
93
94    for (; size > 0; size -= pageSize, vaddr += pageSize) {
95        std::map<Addr,Addr>::iterator iter = pTable.find(vaddr);
96
97        if (iter != pTable.end()) {
98            // already mapped
99            fatal("PageTable::allocate: address 0x%x already mapped", vaddr);
100        }
101
102        pTable[vaddr] = system->new_page();
103    }
104}
105
106
107
108bool
109PageTable::translate(Addr vaddr, Addr &paddr)
110{
111    Addr page_addr = pageAlign(vaddr);
112    std::map<Addr,Addr>::iterator iter = pTable.find(page_addr);
113
114    if (iter == pTable.end()) {
115        return false;
116    }
117
118    paddr = iter->second + pageOffset(vaddr);
119    return true;
120}
121
122
123Fault
124PageTable::translate(RequestPtr &req)
125{
126    Addr paddr;
127    assert(pageAlign(req->getVaddr() + req->getSize() - 1)
128           == pageAlign(req->getVaddr()));
129    if (!translate(req->getVaddr(), paddr)) {
130        return genMachineCheckFault();
131    }
132    req->setPaddr(paddr);
133    return page_check(req->getPaddr(), req->getSize());
134}
135