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
  30 /**
  31  * @file
  32  * Definitions of functional page table.
  33  */
  34 #include "mem/page_table.hh"
  35
  36 #include <string>
  37
  38 #include "base/compiler.hh"
  39 #include "base/trace.hh"
  40 #include "debug/MMU.hh"
  41 #include "sim/faults.hh"
  42 #include "sim/serialize.hh"
  43
  44 void
  45 EmulationPageTable::map(Addr vaddr, Addr paddr, int64_t size, uint64_t flags)
  46 {
  47     bool clobber = flags & Clobber;
  48     // starting address must be page aligned
  49     assert(pageOffset(vaddr) == 0);
  50
  51     DPRINTF(MMU, "Allocating Page: %#x-%#x\n", vaddr, vaddr + size);
  52
  53     while (size > 0) {
  54         auto it = pTable.find(vaddr);
  55         if (it != pTable.end()) {
  56             // already mapped
  57             panic_if(!clobber,
  58                      "EmulationPageTable::allocate: addr %#x already mapped",
  59                      vaddr);
  60             it->second = Entry(paddr, flags);
  61         } else {
  62             pTable.emplace(vaddr, Entry(paddr, flags));
  63         }
  64
  65         size -= _pageSize;
  66         vaddr += _pageSize;
  67         paddr += _pageSize;
  68     }
  69 }
  70
  71 void
  72 EmulationPageTable::remap(Addr vaddr, int64_t size, Addr new_vaddr)
  73 {
  74     assert(pageOffset(vaddr) == 0);
  75     assert(pageOffset(new_vaddr) == 0);
  76
  77     DPRINTF(MMU, "moving pages from vaddr %08p to %08p, size = %d\n", vaddr,
  78             new_vaddr, size);
  79
  80     while (size > 0) {
  81         M5_VAR_USED auto new_it = pTable.find(new_vaddr);
  82         auto old_it = pTable.find(vaddr);
  83         assert(old_it != pTable.end() && new_it == pTable.end());
  84
  85         pTable.emplace(new_vaddr, old_it->second);
  86         pTable.erase(old_it);
  87         size -= _pageSize;
  88         vaddr += _pageSize;
  89         new_vaddr += _pageSize;
  90     }
  91 }
  92
  93 void
  94 EmulationPageTable::getMappings(std::vector<std::pair<Addr, Addr>> *addr_maps)
  95 {
  96     for (auto &iter : pTable)
  97         addr_maps->push_back(std::make_pair(iter.first, iter.second.paddr));
  98 }
  99
 100 void
 101 EmulationPageTable::unmap(Addr vaddr, int64_t size)
 102 {
 103     assert(pageOffset(vaddr) == 0);
 104
 105     DPRINTF(MMU, "Unmapping page: %#x-%#x\n", vaddr, vaddr + size);
 106
 107     while (size > 0) {
 108         auto it = pTable.find(vaddr);
 109         assert(it != pTable.end());
 110         pTable.erase(it);
 111         size -= _pageSize;
 112         vaddr += _pageSize;
 113     }
 114 }
 115
 116 bool
 117 EmulationPageTable::isUnmapped(Addr vaddr, int64_t size)
 118 {
 119     // starting address must be page aligned
 120     assert(pageOffset(vaddr) == 0);
 121
 122     for (int64_t offset = 0; offset < size; offset += _pageSize)
 123         if (pTable.find(vaddr + offset) != pTable.end())
 124             return false;
 125
 126     return true;
 127 }
 128
 129 const EmulationPageTable::Entry *
 130 EmulationPageTable::lookup(Addr vaddr)
 131 {
 132     Addr page_addr = pageAlign(vaddr);
 133     PTableItr iter = pTable.find(page_addr);
 134     if (iter == pTable.end())
 135         return nullptr;
 136     return &(iter->second);
 137 }
 138
 139 bool
 140 EmulationPageTable::translate(Addr vaddr, Addr &paddr)
 141 {
 142     const Entry *entry = lookup(vaddr);
 143     if (!entry) {
 144         DPRINTF(MMU, "Couldn't Translate: %#x\n", vaddr);
 145         return false;
 146     }
 147     paddr = pageOffset(vaddr) + entry->paddr;
 148     DPRINTF(MMU, "Translating: %#x->%#x\n", vaddr, paddr);
 149     return true;
 150 }
 151
 152 Fault
 153 EmulationPageTable::translate(const RequestPtr &req)
 154 {
 155     Addr paddr;
 156     assert(pageAlign(req->getVaddr() + req->getSize() - 1) ==
 157            pageAlign(req->getVaddr()));
 158     if (!translate(req->getVaddr(), paddr))
 159         return Fault(new GenericPageTableFault(req->getVaddr()));
 160     req->setPaddr(paddr);
 161     if ((paddr & (_pageSize - 1)) + req->getSize() > _pageSize) {
 162         panic("Request spans page boundaries!\n");
 163         return NoFault;
 164     }
 165     return NoFault;
 166 }
 167
 168 void
 169 EmulationPageTable::serialize(CheckpointOut &cp) const
 170 {
 171     ScopedCheckpointSection sec(cp, "ptable");
 172     paramOut(cp, "size", pTable.size());
 173
 174     PTable::size_type count = 0;
 175     for (auto &pte : pTable) {
 176         ScopedCheckpointSection sec(cp, csprintf("Entry%d", count++));
 177
 178         paramOut(cp, "vaddr", pte.first);
 179         paramOut(cp, "paddr", pte.second.paddr);
 180         paramOut(cp, "flags", pte.second.flags);
 181     }
 182     assert(count == pTable.size());
 183 }
 184
 185 void
 186 EmulationPageTable::unserialize(CheckpointIn &cp)
 187 {
 188     int count;
 189     ScopedCheckpointSection sec(cp, "ptable");
 190     paramIn(cp, "size", count);
 191
 192     for (int i = 0; i < count; ++i) {
 193         ScopedCheckpointSection sec(cp, csprintf("Entry%d", i));
 194
 195         Addr vaddr;
 196         UNSERIALIZE_SCALAR(vaddr);
 197         Addr paddr;
 198         uint64_t flags;
 199         UNSERIALIZE_SCALAR(paddr);
 200         UNSERIALIZE_SCALAR(flags);
 201
 202         pTable.emplace(vaddr, Entry(paddr, flags));
 203     }
 204 }
 205