src/mem/page_table.hh

   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
  29 /**
  30  * @file
  31  * Declaration of a non-full system Page Table.
  32  */
  33
  34 #ifndef __PAGE_TABLE__
  35 #define __PAGE_TABLE__
  36
  37 #include <string>
  38 #include <map>
  39
  40 #include "arch/isa_traits.hh"
  41 #include "base/trace.hh"
  42 #include "mem/request.hh"
  43 #include "mem/packet.hh"
  44 #include "sim/sim_object.hh"
  45
  46 class System;
  47
  48 /**
  49  * Page Table Decleration.
  50  */
  51 class PageTable
  52 {
  53   protected:
  54     std::map<Addr,Addr> pTable;
  55
  56     const Addr pageSize;
  57     const Addr offsetMask;
  58
  59     System *system;
  60
  61   public:
  62
  63     PageTable(System *_system, Addr _pageSize = TheISA::VMPageSize);
  64
  65     ~PageTable();
  66
  67     Addr pageAlign(Addr a)  { return (a & ~offsetMask); }
  68     Addr pageOffset(Addr a) { return (a &  offsetMask); }
  69
  70     Fault page_check(Addr addr, int size) const;
  71
  72     void allocate(Addr vaddr, int size);
  73
  74     /**
  75      * Translate function
  76      * @param vaddr The virtual address.
  77      * @return Physical address from translation.
  78      */
  79     bool translate(Addr vaddr, Addr &paddr);
  80
  81     /**
  82      * Perform a translation on the memory request, fills in paddr
  83      * field of mem_req.
  84      * @param req The memory request.
  85      */
  86     Fault translate(RequestPtr &req);
  87
  88 };
  89
  90 #endif