--- /dev/null	2018-04-03 12:55:20.301839954 +0200
+++ new/src/hotspot/share/gc/z/zPageAllocator.hpp	2018-06-06 00:42:12.013484480 +0200
@@ -0,0 +1,108 @@
+/*
+ * Copyright (c) 2015, 2017, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+#ifndef SHARE_GC_Z_ZPAGEALLOCATOR_HPP
+#define SHARE_GC_Z_ZPAGEALLOCATOR_HPP
+
+#include "gc/z/zAllocationFlags.hpp"
+#include "gc/z/zList.hpp"
+#include "gc/z/zLock.hpp"
+#include "gc/z/zPageCache.hpp"
+#include "gc/z/zPhysicalMemory.hpp"
+#include "gc/z/zPreMappedMemory.hpp"
+#include "gc/z/zVirtualMemory.hpp"
+#include "memory/allocation.hpp"
+
+class ZPageAllocRequest;
+
+class ZPageAllocator {
+  friend class VMStructs;
+
+private:
+  ZLock                    _lock;
+  ZVirtualMemoryManager    _virtual;
+  ZPhysicalMemoryManager   _physical;
+  ZPageCache               _cache;
+  ZPreMappedMemory         _pre_mapped;
+  const size_t             _max_reserve;
+  size_t                   _used_high;
+  size_t                   _used_low;
+  size_t                   _used;
+  size_t                   _allocated;
+  ssize_t                  _reclaimed;
+  ZList<ZPageAllocRequest> _queue;
+  ZList<ZPage>             _detached;
+
+  static ZPage* const      gc_marker;
+
+  void increase_used(size_t size, bool relocation);
+  void decrease_used(size_t size, bool reclaimed);
+
+  size_t available(ZAllocationFlags flags) const;
+
+  ZPage* create_page(uint8_t type, size_t size);
+  void map_page(ZPage* page);
+  void detach_page(ZPage* page);
+  void flush_pre_mapped();
+  void flush_cache(size_t size);
+
+  void check_out_of_memory_during_initialization();
+
+  ZPage* alloc_page_common_inner(uint8_t type, size_t size, ZAllocationFlags flags);
+  ZPage* alloc_page_common(uint8_t type, size_t size, ZAllocationFlags flags);
+  ZPage* alloc_page_blocking(uint8_t type, size_t size, ZAllocationFlags flags);
+  ZPage* alloc_page_nonblocking(uint8_t type, size_t size, ZAllocationFlags flags);
+
+  void satisfy_alloc_queue();
+
+  void detach_memory(const ZVirtualMemory& vmem, ZPhysicalMemory& pmem);
+
+public:
+  ZPageAllocator(size_t min_capacity, size_t max_capacity, size_t max_reserve);
+
+  bool is_initialized() const;
+
+  size_t max_capacity() const;
+  size_t capacity() const;
+  size_t max_reserve() const;
+  size_t used_high() const;
+  size_t used_low() const;
+  size_t used() const;
+  size_t allocated() const;
+  size_t reclaimed() const;
+
+  void reset_statistics();
+
+  ZPage* alloc_page(uint8_t type, size_t size, ZAllocationFlags flags);
+  void flip_page(ZPage* page);
+  void free_page(ZPage* page, bool reclaimed);
+  void destroy_page(ZPage* page);
+
+  void flush_detached_pages(ZList<ZPage>* list);
+
+  void flip_pre_mapped();
+
+  void check_out_of_memory();
+};
+
+#endif // SHARE_GC_Z_ZPAGEALLOCATOR_HPP