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 * Ali Saidi
31 */
32
33/**
34 * @file
35 * Definitions of page table.
36 */
37#include <fstream>
38#include <map>
39#include <string>
40
41#include "base/bitfield.hh"
42#include "base/intmath.hh"
43#include "base/trace.hh"
44#include "config/the_isa.hh"
45#include "debug/MMU.hh"
46#include "mem/page_table.hh"
47#include "sim/faults.hh"
48#include "sim/process.hh"
49#include "sim/sim_object.hh"
50#include "sim/system.hh"
51
52using namespace std;
53using namespace TheISA;
54
55PageTable::PageTable(Process *_process, Addr _pageSize)
56 : pageSize(_pageSize), offsetMask(mask(floorLog2(_pageSize))),
57 process(_process)
58{
59 assert(isPowerOf2(pageSize));
60 pTableCache[0].vaddr = 0;
61 pTableCache[1].vaddr = 0;
62 pTableCache[2].vaddr = 0;
63}
64
65PageTable::~PageTable()
66{
67}
68
69void
70PageTable::allocate(Addr vaddr, int64_t size)
71{
72 // starting address must be page aligned
73 assert(pageOffset(vaddr) == 0);
74
75 DPRINTF(MMU, "Allocating Page: %#x-%#x\n", vaddr, vaddr+ size);
76
77 for (; size > 0; size -= pageSize, vaddr += pageSize) {
78 PTableItr iter = pTable.find(vaddr);
79
80 if (iter != pTable.end()) {
81 // already mapped
82 fatal("PageTable::allocate: address 0x%x already mapped",
83 vaddr);
84 }
85
86 pTable[vaddr] = TheISA::TlbEntry(process->M5_pid, vaddr,
87 process->system->new_page());
88 updateCache(vaddr, pTable[vaddr]);
89 }
90}
91
92void
93PageTable::remap(Addr vaddr, int64_t size, Addr new_vaddr)
94{
95 assert(pageOffset(vaddr) == 0);
96 assert(pageOffset(new_vaddr) == 0);
97
98 DPRINTF(MMU, "moving pages from vaddr %08p to %08p, size = %d\n", vaddr,
99 new_vaddr, size);
100
101 for (; size > 0; size -= pageSize, vaddr += pageSize, new_vaddr += pageSize) {
102 PTableItr iter = pTable.find(vaddr);
103
104 assert(iter != pTable.end());
105
106 pTable[new_vaddr] = pTable[vaddr];
107 pTable.erase(vaddr);
108 pTable[new_vaddr].updateVaddr(new_vaddr);
109 updateCache(new_vaddr, pTable[new_vaddr]);
110 }
111}
112
113void
114PageTable::deallocate(Addr vaddr, int64_t size)
115{
116 assert(pageOffset(vaddr) == 0);
117
118 DPRINTF(MMU, "Deallocating page: %#x-%#x\n", vaddr, vaddr+ size);
119
120 for (; size > 0; size -= pageSize, vaddr += pageSize) {
121 PTableItr iter = pTable.find(vaddr);
122
123 assert(iter != pTable.end());
124
125 pTable.erase(vaddr);
126 }
127
128}
129
130bool
131PageTable::lookup(Addr vaddr, TheISA::TlbEntry &entry)
132{
133 Addr page_addr = pageAlign(vaddr);
134
135 if (pTableCache[0].vaddr == page_addr) {
136 entry = pTableCache[0].entry;
137 return true;
138 }
139 if (pTableCache[1].vaddr == page_addr) {
140 entry = pTableCache[1].entry;
141 return true;
142 }
143 if (pTableCache[2].vaddr == page_addr) {
144 entry = pTableCache[2].entry;
145 return true;
146 }
147
148 PTableItr iter = pTable.find(page_addr);
149
150 if (iter == pTable.end()) {
151 return false;
152 }
153
154 updateCache(page_addr, iter->second);
155 entry = iter->second;
156 return true;
157}
158
159bool
160PageTable::translate(Addr vaddr, Addr &paddr)
161{
162 TheISA::TlbEntry entry;
163 if (!lookup(vaddr, entry)) {
164 DPRINTF(MMU, "Couldn't Translate: %#x\n", vaddr);
165 return false;
166 }
167 paddr = pageOffset(vaddr) + entry.pageStart();
168 DPRINTF(MMU, "Translating: %#x->%#x\n", vaddr, paddr);
169 return true;
170}
171
172Fault
173PageTable::translate(RequestPtr req)
174{
175 Addr paddr;
176 assert(pageAlign(req->getVaddr() + req->getSize() - 1)
177 == pageAlign(req->getVaddr()));
178 if (!translate(req->getVaddr(), paddr)) {
179 return Fault(new GenericPageTableFault(req->getVaddr()));
180 }
181 req->setPaddr(paddr);
182 if ((paddr & (pageSize - 1)) + req->getSize() > pageSize) {
183 panic("Request spans page boundaries!\n");
184 return NoFault;
185 }
186 return NoFault;
187}
188
189void
190PageTable::serialize(std::ostream &os)
191{
192 paramOut(os, "ptable.size", pTable.size());
193
194 PTable::size_type count = 0;
195
196 PTableItr iter = pTable.begin();
197 PTableItr end = pTable.end();
198 while (iter != end) {
199 os << "\n[" << csprintf("%s.Entry%d", process->name(), count) << "]\n";
200
201 paramOut(os, "vaddr", iter->first);
202 iter->second.serialize(os);
203
204 ++iter;
205 ++count;
206 }
207 assert(count == pTable.size());
208}
209
210void
211PageTable::unserialize(Checkpoint *cp, const std::string &section)
212{
213 int i = 0, count;
214 paramIn(cp, section, "ptable.size", count);
215
216 pTable.clear();
217
218 while (i < count) {
219 TheISA::TlbEntry *entry;
220 Addr vaddr;
221
222 paramIn(cp, csprintf("%s.Entry%d", process->name(), i), "vaddr", vaddr);
223 entry = new TheISA::TlbEntry();
224 entry->unserialize(cp, csprintf("%s.Entry%d", process->name(), i));
225 pTable[vaddr] = *entry;
226 ++i;
227 }
228}
229