page_table.cc revision 2399 
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 "base/bitfield.hh"
38#include "base/intmath.hh"
39#include "base/trace.hh"
40#include "mem/page_table.hh"
41#include "sim/builder.hh"
42#include "sim/sim_object.hh"
43#include "sim/system.hh"
44
45using namespace std;
46
47PageTable::PageTable(System *_system, Addr _pageSize)
48    : pageSize(_pageSize), offsetMask(mask(floorLog2(_pageSize))),
49      system(_system)
50{
51    assert(isPowerOf2(pageSize));
52}
53
54PageTable::~PageTable()
55{
56}
57
58Fault
59PageTable::page_check(Addr addr, int size) const
60{
61    if (size < sizeof(uint64_t)) {
62        if (!isPowerOf2(size)) {
63            panic("Invalid request size!\n");
64            return Machine_Check_Fault;
65        }
66
67        if ((size - 1) & addr)
68            return Alignment_Fault;
69    }
70    else {
71        if ((addr & (VMPageSize - 1)) + size > VMPageSize) {
72            panic("Invalid request size!\n");
73            return Machine_Check_Fault;
74        }
75
76        if ((sizeof(uint64_t) - 1) & addr)
77            return Alignment_Fault;
78    }
79
80    return No_Fault;
81}
82
83
84
85
86void
87PageTable::allocate(Addr vaddr, int size)
88{
89    // starting address must be page aligned
90    assert(pageOffset(vaddr) == 0);
91
92    for (; size > 0; size -= pageSize, vaddr += pageSize) {
93        std::map<Addr,Addr>::iterator iter = pTable.find(vaddr);
94
95        if (iter != pTable.end()) {
96            // already mapped
97            fatal("PageTable::allocate: address 0x%x already mapped", vaddr);
98        }
99
100        pTable[vaddr] = system->new_page();
101    }
102}
103
104
105
106bool
107PageTable::translate(Addr vaddr, Addr &paddr)
108{
109    Addr page_addr = pageAlign(vaddr);
110    std::map<Addr,Addr>::iterator iter = pTable.find(page_addr);
111
112    if (iter == pTable.end()) {
113        return false;
114    }
115
116    paddr = iter->second + pageOffset(vaddr);
117    return true;
118}
119
120
121Fault
122PageTable::translate(CpuRequestPtr &req)
123{
124    assert(pageAlign(req->vaddr + req->size - 1) == pageAlign(req->vaddr));
125    if (!translate(req->vaddr, req->paddr)) {
126        return Machine_Check_Fault;
127    }
128    return page_check(req->paddr, req->size);
129}
130