1 /*
   2  * Copyright (c) 2015, 2018, 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_CPU_HEADER(gc/z/zPhysicalMemoryBacking)
  29 
  30 class ZPhysicalMemorySegment {
  31 private:
  32   uintptr_t _start;
  33   uintptr_t _end;
  34 
  35 public:
  36   ZPhysicalMemorySegment(uintptr_t start, size_t size);
  37 
  38   uintptr_t start() const;
  39   uintptr_t end() const;
  40   size_t size() const;
  41 
  42   void expand(size_t size);
  43   ZPhysicalMemorySegment split(size_t size);
  44 };
  45 
  46 class ZPhysicalMemory {
  47 private:
  48   size_t                  _nsegments;
  49   ZPhysicalMemorySegment* _segments;
  50 
  51 public:
  52   ZPhysicalMemory();
  53   ZPhysicalMemory(size_t size);
  54   ZPhysicalMemory(const ZPhysicalMemorySegment& segment);
  55 
  56   bool is_null() const;
  57   size_t size() const;
  58 
  59   size_t nsegments() const;
  60   ZPhysicalMemorySegment segment(size_t index) const;
  61   void add_segment(ZPhysicalMemorySegment segment);
  62 
  63   ZPhysicalMemory split(size_t size);
  64   void clear();
  65 };
  66 
  67 class ZPhysicalMemoryManager {
  68   friend class VMStructs;
  69 
  70 private:
  71   ZPhysicalMemoryBacking _backing;
  72   const size_t           _max_capacity;
  73   size_t                 _current_max_capacity;
  74   size_t                 _capacity;
  75   size_t                 _used;
  76 
  77   void nmt_commit(ZPhysicalMemory pmem, uintptr_t offset);
  78   void nmt_uncommit(ZPhysicalMemory pmem, uintptr_t offset);
  79 
  80 public:
  81   ZPhysicalMemoryManager(size_t max_capacity, size_t granule_size);
  82 
  83   bool is_initialized() const;
  84 
  85   size_t max_capacity() const;
  86   size_t current_max_capacity() const;
  87   size_t capacity() const;
  88   size_t unused_capacity() const;
  89 
  90   void try_ensure_unused_capacity(size_t size);
  91 
  92   ZPhysicalMemory alloc(size_t size);
  93   void free(ZPhysicalMemory pmem);
  94 
  95   void map(ZPhysicalMemory pmem, uintptr_t offset);
  96   void unmap(ZPhysicalMemory pmem, uintptr_t offset);
  97   void flip(ZPhysicalMemory pmem, uintptr_t offset);
  98 };
  99 
 100 #endif // SHARE_GC_Z_ZPHYSICALMEMORY_HPP