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  * Authors: Steve Reinhardt
  29  */
  30
  31 /**
  32  * @file
  33  * Declaration of a non-full system Page Table.
  34  */
  35
  36 #ifndef __MEM_PAGE_TABLE_HH__
  37 #define __MEM_PAGE_TABLE_HH__
  38
  39 #include <string>
  40
  41 #include "arch/isa_traits.hh"
  42 #include "arch/tlb.hh"
  43 #include "base/hashmap.hh"
  44 #include "base/types.hh"
  45 #include "config/the_isa.hh"
  46 #include "mem/request.hh"
  47 #include "sim/serialize.hh"
  48
  49 /**
  50  * Page Table Declaration.
  51  */
  52 class PageTable
  53 {
  54   protected:
  55     typedef m5::hash_map<Addr, TheISA::TlbEntry> PTable;
  56     typedef PTable::iterator PTableItr;
  57     PTable pTable;
  58
  59     struct cacheElement {
  60         Addr vaddr;
  61         TheISA::TlbEntry entry;
  62     };
  63
  64     struct cacheElement pTableCache[3];
  65
  66     const Addr pageSize;
  67     const Addr offsetMask;
  68
  69     const uint64_t pid;
  70     const std::string _name;
  71
  72   public:
  73
  74     PageTable(const std::string &__name, uint64_t _pid,
  75               Addr _pageSize = TheISA::VMPageSize);
  76
  77     ~PageTable();
  78
  79     // for DPRINTF compatibility
  80     const std::string name() const { return _name; }
  81
  82     Addr pageAlign(Addr a)  { return (a & ~offsetMask); }
  83     Addr pageOffset(Addr a) { return (a &  offsetMask); }
  84
  85     void map(Addr vaddr, Addr paddr, int64_t size, bool clobber = false);
  86     void remap(Addr vaddr, int64_t size, Addr new_vaddr);
  87     void unmap(Addr vaddr, int64_t size);
  88
  89     /**
  90      * Check if any pages in a region are already allocated
  91      * @param vaddr The starting virtual address of the region.
  92      * @param size The length of the region.
  93      * @return True if no pages in the region are mapped.
  94      */
  95     bool isUnmapped(Addr vaddr, int64_t size);
  96
  97     /**
  98      * Lookup function
  99      * @param vaddr The virtual address.
 100      * @return entry The page table entry corresponding to vaddr.
 101      */
 102     bool lookup(Addr vaddr, TheISA::TlbEntry &entry);
 103
 104     /**
 105      * Translate function
 106      * @param vaddr The virtual address.
 107      * @param paddr Physical address from translation.
 108      * @return True if translation exists
 109      */
 110     bool translate(Addr vaddr, Addr &paddr);
 111
 112     /**
 113      * Simplified translate function (just check for translation)
 114      * @param vaddr The virtual address.
 115      * @return True if translation exists
 116      */
 117     bool translate(Addr vaddr) { Addr dummy; return translate(vaddr, dummy); }
 118
 119     /**
 120      * Perform a translation on the memory request, fills in paddr
 121      * field of req.
 122      * @param req The memory request.
 123      */
 124     Fault translate(RequestPtr req);
 125
 126     /**
 127      * Update the page table cache.
 128      * @param vaddr virtual address (page aligned) to check
 129      * @param pte page table entry to return
 130      */
 131     inline void updateCache(Addr vaddr, TheISA::TlbEntry entry)
 132     {
 133         pTableCache[2].entry = pTableCache[1].entry;
 134         pTableCache[2].vaddr = pTableCache[1].vaddr;
 135         pTableCache[1].entry = pTableCache[0].entry;
 136         pTableCache[1].vaddr = pTableCache[0].vaddr;
 137         pTableCache[0].entry = entry;
 138         pTableCache[0].vaddr = vaddr;
 139     }
 140
 141
 142     void serialize(std::ostream &os);
 143
 144     void unserialize(Checkpoint *cp, const std::string &section);
 145 };
 146
 147 #endif // __MEM_PAGE_TABLE_HH__