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 "debug/MMU.hh"
  44 #include "sim/faults.hh"
  45 #include "sim/serialize.hh"
  46
  47 using namespace std;
  48
  49 void
  50 EmulationPageTable::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
  76 void
  77 EmulationPageTable::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         new_it->second = old_it->second;
  91         pTable.erase(old_it);
  92         size -= pageSize;
  93         vaddr += pageSize;
  94         new_vaddr += pageSize;
  95     }
  96 }
  97
  98 void
  99 EmulationPageTable::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
 105 void
 106 EmulationPageTable::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
 121 bool
 122 EmulationPageTable::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
 134 const EmulationPageTable::Entry *
 135 EmulationPageTable::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
 144 bool
 145 EmulationPageTable::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
 157 Fault
 158 EmulationPageTable::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
 173 void
 174 EmulationPageTable::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
 189 void
 190 EmulationPageTable::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