src/mem/page_table.hh

   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  * Declarations of a non-full system Page Table.
  33  */
  34
  35 #ifndef __MEM_PAGE_TABLE_HH__
  36 #define __MEM_PAGE_TABLE_HH__
  37
  38 #include <string>
  39 #include <unordered_map>
  40
  41 #include "base/intmath.hh"
  42 #include "base/types.hh"
  43 #include "mem/request.hh"
  44 #include "sim/serialize.hh"
  45
  46 class ThreadContext;
  47
  48 class EmulationPageTable : public Serializable
  49 {
  50   public:
  51     struct Entry
  52     {
  53         Addr paddr;
  54         uint64_t flags;
  55
  56         Entry(Addr paddr, uint64_t flags) : paddr(paddr), flags(flags) {}
  57         Entry() {}
  58     };
  59
  60   protected:
  61     typedef std::unordered_map<Addr, Entry> PTable;
  62     typedef PTable::iterator PTableItr;
  63     PTable pTable;
  64
  65     const Addr pageSize;
  66     const Addr offsetMask;
  67
  68     const uint64_t _pid;
  69     const std::string _name;
  70
  71   public:
  72
  73     EmulationPageTable(
  74             const std::string &__name, uint64_t _pid, Addr _pageSize) :
  75             pageSize(_pageSize), offsetMask(mask(floorLog2(_pageSize))),
  76             _pid(_pid), _name(__name), shared(false)
  77     {
  78         assert(isPowerOf2(pageSize));
  79     }
  80
  81     uint64_t pid() const { return _pid; };
  82
  83     virtual ~EmulationPageTable() {};
  84
  85     /* generic page table mapping flags
  86      *              unset | set
  87      * bit 0 - no-clobber | clobber
  88      * bit 2 - cacheable  | uncacheable
  89      * bit 3 - read-write | read-only
  90      */
  91     enum MappingFlags : uint32_t {
  92         Clobber     = 1,
  93         Uncacheable = 4,
  94         ReadOnly    = 8,
  95     };
  96
  97     // flag which marks the page table as shared among software threads
  98     bool shared;
  99
 100     virtual void initState() {};
 101
 102     // for DPRINTF compatibility
 103     const std::string name() const { return _name; }
 104
 105     Addr pageAlign(Addr a)  { return (a & ~offsetMask); }
 106     Addr pageOffset(Addr a) { return (a &  offsetMask); }
 107
 108     /**
 109      * Maps a virtual memory region to a physical memory region.
 110      * @param vaddr The starting virtual address of the region.
 111      * @param paddr The starting physical address where the region is mapped.
 112      * @param size The length of the region.
 113      * @param flags Generic mapping flags that can be set by or-ing values
 114      *              from MappingFlags enum.
 115      */
 116     virtual void map(Addr vaddr, Addr paddr, int64_t size, uint64_t flags = 0);
 117     virtual void remap(Addr vaddr, int64_t size, Addr new_vaddr);
 118     virtual void unmap(Addr vaddr, int64_t size);
 119
 120     /**
 121      * Check if any pages in a region are already allocated
 122      * @param vaddr The starting virtual address of the region.
 123      * @param size The length of the region.
 124      * @return True if no pages in the region are mapped.
 125      */
 126     virtual bool isUnmapped(Addr vaddr, int64_t size);
 127
 128     /**
 129      * Lookup function
 130      * @param vaddr The virtual address.
 131      * @return The page table entry corresponding to vaddr.
 132      */
 133     const Entry *lookup(Addr vaddr);
 134
 135     /**
 136      * Translate function
 137      * @param vaddr The virtual address.
 138      * @param paddr Physical address from translation.
 139      * @return True if translation exists
 140      */
 141     bool translate(Addr vaddr, Addr &paddr);
 142
 143     /**
 144      * Simplified translate function (just check for translation)
 145      * @param vaddr The virtual address.
 146      * @return True if translation exists
 147      */
 148     bool translate(Addr vaddr) { Addr dummy; return translate(vaddr, dummy); }
 149
 150     /**
 151      * Perform a translation on the memory request, fills in paddr
 152      * field of req.
 153      * @param req The memory request.
 154      */
 155     Fault translate(const RequestPtr &req);
 156
 157     void getMappings(std::vector<std::pair<Addr, Addr>> *addr_mappings);
 158
 159     void serialize(CheckpointOut &cp) const override;
 160     void unserialize(CheckpointIn &cp) override;
 161 };
 162
 163 #endif // __MEM_PAGE_TABLE_HH__