page_table.hh revision 2809:9cb5fba079ed 
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 "arch/isa_traits.hh"
42#include "base/hashmap.hh"
43#include "base/trace.hh"
44#include "mem/request.hh"
45#include "mem/packet.hh"
46#include "sim/sim_object.hh"
47
48class System;
49
50/**
51 * Page Table Decleration.
52 */
53class PageTable
54{
55  protected:
56    m5::hash_map<Addr,Addr> pTable;
57
58    struct cacheElement {
59        Addr paddr;
60        Addr vaddr;
61    } ;
62
63    struct cacheElement pTableCache[3];
64
65    const Addr pageSize;
66    const Addr offsetMask;
67
68    System *system;
69
70  public:
71
72    PageTable(System *_system, Addr _pageSize = TheISA::VMPageSize);
73
74    ~PageTable();
75
76    Addr pageAlign(Addr a)  { return (a & ~offsetMask); }
77    Addr pageOffset(Addr a) { return (a &  offsetMask); }
78
79    Fault page_check(Addr addr, int size) const;
80
81    void allocate(Addr vaddr, int size);
82
83    /**
84     * Translate function
85     * @param vaddr The virtual address.
86     * @return Physical address from translation.
87     */
88    bool translate(Addr vaddr, Addr &paddr);
89
90    /**
91     * Perform a translation on the memory request, fills in paddr
92     * field of mem_req.
93     * @param req The memory request.
94     */
95    Fault translate(RequestPtr &req);
96
97};
98
99#endif
100