src/mem/page_table.cc

   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 "config/the_isa.hh"
  44 #include "debug/MMU.hh"
  45 #include "sim/faults.hh"
  46 #include "sim/serialize.hh"
  47
  48 using namespace std;
  49 using namespace TheISA;
  50
  51 EmulationPageTable::~EmulationPageTable()
  52 {
  53     for (auto &iter : pTable)
  54         delete iter.second;
  55 }
  56
  57 void
  58 EmulationPageTable::map(Addr vaddr, Addr paddr, int64_t size, uint64_t flags)
  59 {
  60     bool clobber = flags & Clobber;
  61     // starting address must be page aligned
  62     assert(pageOffset(vaddr) == 0);
  63
  64     DPRINTF(MMU, "Allocating Page: %#x-%#x\n", vaddr, vaddr + size);
  65
  66     while (size > 0) {
  67         auto it = pTable.find(vaddr);
  68         if (it != pTable.end()) {
  69             if (clobber) {
  70                 delete it->second;
  71             } else {
  72                 // already mapped
  73                 fatal("EmulationPageTable::allocate: addr %#x already mapped",
  74                       vaddr);
  75             }
  76         } else {
  77             it = pTable.emplace(vaddr, nullptr).first;
  78         }
  79
  80         it->second = new TheISA::TlbEntry(pid, vaddr, paddr,
  81                                          flags & Uncacheable,
  82                                          flags & ReadOnly);
  83         size -= pageSize;
  84         vaddr += pageSize;
  85         paddr += pageSize;
  86     }
  87 }
  88
  89 void
  90 EmulationPageTable::remap(Addr vaddr, int64_t size, Addr new_vaddr)
  91 {
  92     assert(pageOffset(vaddr) == 0);
  93     assert(pageOffset(new_vaddr) == 0);
  94
  95     DPRINTF(MMU, "moving pages from vaddr %08p to %08p, size = %d\n", vaddr,
  96             new_vaddr, size);
  97
  98     while (size > 0) {
  99         auto new_it = pTable.find(new_vaddr);
 100         auto old_it = pTable.find(vaddr);
 101         assert(old_it != pTable.end() && new_it == pTable.end());
 102
 103         new_it->second = old_it->second;
 104         pTable.erase(old_it);
 105         new_it->second->updateVaddr(new_vaddr);
 106         size -= pageSize;
 107         vaddr += pageSize;
 108         new_vaddr += pageSize;
 109     }
 110 }
 111
 112 void
 113 EmulationPageTable::getMappings(std::vector<std::pair<Addr, Addr>> *addr_maps)
 114 {
 115     for (auto &iter : pTable)
 116         addr_maps->push_back(make_pair(iter.first, iter.second->pageStart()));
 117 }
 118
 119 void
 120 EmulationPageTable::unmap(Addr vaddr, int64_t size)
 121 {
 122     assert(pageOffset(vaddr) == 0);
 123
 124     DPRINTF(MMU, "Unmapping page: %#x-%#x\n", vaddr, vaddr+ size);
 125
 126     while (size > 0) {
 127         auto it = pTable.find(vaddr);
 128         assert(it != pTable.end());
 129         delete it->second;
 130         pTable.erase(it);
 131         size -= pageSize;
 132         vaddr += pageSize;
 133     }
 134 }
 135
 136 bool
 137 EmulationPageTable::isUnmapped(Addr vaddr, int64_t size)
 138 {
 139     // starting address must be page aligned
 140     assert(pageOffset(vaddr) == 0);
 141
 142     for (int64_t offset = 0; offset < size; offset += pageSize)
 143         if (pTable.find(vaddr + offset) != pTable.end())
 144             return false;
 145
 146     return true;
 147 }
 148
 149 TheISA::TlbEntry *
 150 EmulationPageTable::lookup(Addr vaddr)
 151 {
 152     Addr page_addr = pageAlign(vaddr);
 153     PTableItr iter = pTable.find(page_addr);
 154     if (iter == pTable.end())
 155         return nullptr;
 156     return iter->second;
 157 }
 158
 159 bool
 160 EmulationPageTable::translate(Addr vaddr, Addr &paddr)
 161 {
 162     TheISA::TlbEntry *entry = lookup(vaddr);
 163     if (!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
 172 Fault
 173 EmulationPageTable::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     req->setPaddr(paddr);
 181     if ((paddr & (pageSize - 1)) + req->getSize() > pageSize) {
 182         panic("Request spans page boundaries!\n");
 183         return NoFault;
 184     }
 185     return NoFault;
 186 }
 187
 188 void
 189 EmulationPageTable::serialize(CheckpointOut &cp) const
 190 {
 191     paramOut(cp, "ptable.size", pTable.size());
 192
 193     PTable::size_type count = 0;
 194     for (auto &pte : pTable) {
 195         ScopedCheckpointSection sec(cp, csprintf("Entry%d", count++));
 196
 197         paramOut(cp, "vaddr", pte.first);
 198         pte.second->serialize(cp);
 199     }
 200     assert(count == pTable.size());
 201 }
 202
 203 void
 204 EmulationPageTable::unserialize(CheckpointIn &cp)
 205 {
 206     int count;
 207     paramIn(cp, "ptable.size", count);
 208
 209     for (int i = 0; i < count; ++i) {
 210         ScopedCheckpointSection sec(cp, csprintf("Entry%d", i));
 211
 212         TheISA::TlbEntry *entry = new TheISA::TlbEntry();
 213         entry->unserialize(cp);
 214
 215         Addr vaddr;
 216         paramIn(cp, "vaddr", vaddr);
 217
 218         pTable[vaddr] = entry;
 219     }
 220 }
 221