page_table.cc revision 12519 
1/*
2 * Copyright (c) 2014 Advanced Micro Devices, Inc.
3 * Copyright (c) 2003 The Regents of The University of Michigan
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are
8 * met: redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer;
10 * redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution;
13 * neither the name of the copyright holders nor the names of its
14 * contributors may be used to endorse or promote products derived from
15 * this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
18 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
20 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
21 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
22 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
23 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 *
29 * Authors: Steve Reinhardt
30 *          Ron Dreslinski
31 *          Ali Saidi
32 */
33
34/**
35 * @file
36 * Definitions of functional page table.
37 */
38#include "mem/page_table.hh"
39
40#include <string>
41
42#include "base/trace.hh"
43#include "debug/MMU.hh"
44#include "sim/faults.hh"
45#include "sim/serialize.hh"
46
47using namespace std;
48
49void
50EmulationPageTable::map(Addr vaddr, Addr paddr, int64_t size, uint64_t flags)
51{
52    bool clobber = flags & Clobber;
53    // starting address must be page aligned
54    assert(pageOffset(vaddr) == 0);
55
56    DPRINTF(MMU, "Allocating Page: %#x-%#x\n", vaddr, vaddr + size);
57
58    while (size > 0) {
59        auto it = pTable.find(vaddr);
60        if (it != pTable.end()) {
61            // already mapped
62            panic_if(!clobber,
63                     "EmulationPageTable::allocate: addr %#x already mapped",
64                     vaddr);
65            it->second = Entry(paddr, flags);
66        } else {
67            pTable.emplace(vaddr, Entry(paddr, flags));
68        }
69
70        size -= pageSize;
71        vaddr += pageSize;
72        paddr += pageSize;
73    }
74}
75
76void
77EmulationPageTable::remap(Addr vaddr, int64_t size, Addr new_vaddr)
78{
79    assert(pageOffset(vaddr) == 0);
80    assert(pageOffset(new_vaddr) == 0);
81
82    DPRINTF(MMU, "moving pages from vaddr %08p to %08p, size = %d\n", vaddr,
83            new_vaddr, size);
84
85    while (size > 0) {
86        auto new_it = pTable.find(new_vaddr);
87        auto old_it = pTable.find(vaddr);
88        assert(old_it != pTable.end() && new_it == pTable.end());
89
90        pTable.emplace(new_vaddr, old_it->second);
91        pTable.erase(old_it);
92        size -= pageSize;
93        vaddr += pageSize;
94        new_vaddr += pageSize;
95    }
96}
97
98void
99EmulationPageTable::getMappings(std::vector<std::pair<Addr, Addr>> *addr_maps)
100{
101    for (auto &iter : pTable)
102        addr_maps->push_back(make_pair(iter.first, iter.second.paddr));
103}
104
105void
106EmulationPageTable::unmap(Addr vaddr, int64_t size)
107{
108    assert(pageOffset(vaddr) == 0);
109
110    DPRINTF(MMU, "Unmapping page: %#x-%#x\n", vaddr, vaddr + size);
111
112    while (size > 0) {
113        auto it = pTable.find(vaddr);
114        assert(it != pTable.end());
115        pTable.erase(it);
116        size -= pageSize;
117        vaddr += pageSize;
118    }
119}
120
121bool
122EmulationPageTable::isUnmapped(Addr vaddr, int64_t size)
123{
124    // starting address must be page aligned
125    assert(pageOffset(vaddr) == 0);
126
127    for (int64_t offset = 0; offset < size; offset += pageSize)
128        if (pTable.find(vaddr + offset) != pTable.end())
129            return false;
130
131    return true;
132}
133
134const EmulationPageTable::Entry *
135EmulationPageTable::lookup(Addr vaddr)
136{
137    Addr page_addr = pageAlign(vaddr);
138    PTableItr iter = pTable.find(page_addr);
139    if (iter == pTable.end())
140        return nullptr;
141    return &(iter->second);
142}
143
144bool
145EmulationPageTable::translate(Addr vaddr, Addr &paddr)
146{
147    const Entry *entry = lookup(vaddr);
148    if (!entry) {
149        DPRINTF(MMU, "Couldn't Translate: %#x\n", vaddr);
150        return false;
151    }
152    paddr = pageOffset(vaddr) + entry->paddr;
153    DPRINTF(MMU, "Translating: %#x->%#x\n", vaddr, paddr);
154    return true;
155}
156
157Fault
158EmulationPageTable::translate(RequestPtr req)
159{
160    Addr paddr;
161    assert(pageAlign(req->getVaddr() + req->getSize() - 1) ==
162           pageAlign(req->getVaddr()));
163    if (!translate(req->getVaddr(), paddr))
164        return Fault(new GenericPageTableFault(req->getVaddr()));
165    req->setPaddr(paddr);
166    if ((paddr & (pageSize - 1)) + req->getSize() > pageSize) {
167        panic("Request spans page boundaries!\n");
168        return NoFault;
169    }
170    return NoFault;
171}
172
173void
174EmulationPageTable::serialize(CheckpointOut &cp) const
175{
176    paramOut(cp, "ptable.size", pTable.size());
177
178    PTable::size_type count = 0;
179    for (auto &pte : pTable) {
180        ScopedCheckpointSection sec(cp, csprintf("Entry%d", count++));
181
182        paramOut(cp, "vaddr", pte.first);
183        paramOut(cp, "paddr", pte.second.paddr);
184        paramOut(cp, "flags", pte.second.flags);
185    }
186    assert(count == pTable.size());
187}
188
189void
190EmulationPageTable::unserialize(CheckpointIn &cp)
191{
192    int count;
193    paramIn(cp, "ptable.size", count);
194
195    for (int i = 0; i < count; ++i) {
196        ScopedCheckpointSection sec(cp, csprintf("Entry%d", i));
197
198        Addr vaddr;
199        UNSERIALIZE_SCALAR(vaddr);
200        Addr paddr;
201        uint64_t flags;
202        UNSERIALIZE_SCALAR(paddr);
203        UNSERIALIZE_SCALAR(flags);
204
205        pTable.emplace(vaddr, Entry(paddr, flags));
206    }
207}
208
209