1 /*
   2  * Copyright (c) 2015, 2019, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 #ifndef SHARE_GC_Z_ZPHYSICALMEMORY_HPP
  25 #define SHARE_GC_Z_ZPHYSICALMEMORY_HPP
  26 
  27 #include "memory/allocation.hpp"
  28 #include OS_HEADER(gc/z/zPhysicalMemoryBacking)
  29 
  30 class ZPhysicalMemorySegment : public CHeapObj<mtGC> {
  31 private:
  32   uintptr_t _start;
  33   uintptr_t _end;
  34 
  35 public:
  36   ZPhysicalMemorySegment();
  37   ZPhysicalMemorySegment(uintptr_t start, size_t size);
  38 
  39   uintptr_t start() const;
  40   uintptr_t end() const;
  41   size_t size() const;
  42 };
  43 
  44 class ZPhysicalMemory {
  45 private:
  46   size_t                  _nsegments;
  47   ZPhysicalMemorySegment* _segments;
  48 
  49 public:
  50   ZPhysicalMemory();
  51   ZPhysicalMemory(const ZPhysicalMemorySegment& segment);
  52   ZPhysicalMemory(const ZPhysicalMemory& pmem);
  53   const ZPhysicalMemory& operator=(const ZPhysicalMemory& pmem);
  54   ~ZPhysicalMemory();
  55 
  56   bool is_null() const;
  57   size_t size() const;
  58 
  59   size_t nsegments() const;
  60   const ZPhysicalMemorySegment& segment(size_t index) const;
  61   void add_segment(const ZPhysicalMemorySegment& segment);
  62 
  63   ZPhysicalMemory split(size_t size);
  64 };
  65 
  66 class ZPhysicalMemoryManager {
  67 private:
  68   ZPhysicalMemoryBacking _backing;
  69 
  70   void nmt_commit(const ZPhysicalMemory& pmem, uintptr_t offset) const;
  71   void nmt_uncommit(const ZPhysicalMemory& pmem, uintptr_t offset) const;
  72 
  73 public:
  74   bool is_initialized() const;
  75 
  76   void warn_commit_limits(size_t max) const;
  77   bool supports_uncommit();
  78 
  79   size_t commit(size_t size);
  80   size_t uncommit(size_t size);
  81 
  82   ZPhysicalMemory alloc(size_t size);
  83   void free(const ZPhysicalMemory& pmem);
  84 
  85   void pretouch(uintptr_t offset, size_t size) const;
  86 
  87   void map(const ZPhysicalMemory& pmem, uintptr_t offset) const;
  88   void unmap(const ZPhysicalMemory& pmem, uintptr_t offset) const;
  89 
  90   void debug_map(const ZPhysicalMemory& pmem, uintptr_t offset) const;
  91   void debug_unmap(const ZPhysicalMemory& pmem, uintptr_t offset) const;
  92 };
  93 
  94 #endif // SHARE_GC_Z_ZPHYSICALMEMORY_HPP