1 /* 2 * Copyright (c) 2015, 2017, 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 #include "precompiled.hpp" 25 #include "gc/z/zGlobals.hpp" 26 #include "gc/z/zVirtualMemory.inline.hpp" 27 28 ZVirtualMemoryManager::ZVirtualMemoryManager() : 29 _manager(), 30 _initialized(false) { 31 // Reserve address space 32 if (!reserve(ZAddressSpaceStart, ZAddressSpaceSize)) { 33 return; 34 } 35 36 // Make the complete address view free 37 _manager.free(0, ZAddressOffsetMax); 38 39 // Successfully initialized 40 _initialized = true; 41 } 42 43 bool ZVirtualMemoryManager::is_initialized() const { 44 return _initialized; 45 } 46 47 ZVirtualMemory ZVirtualMemoryManager::alloc(size_t size, bool alloc_from_front) { 48 uintptr_t start; 49 50 if (alloc_from_front || size <= ZPageSizeSmall) { 51 // Small page 52 start = _manager.alloc_from_front(size); 53 } else { 54 // Medium/Large page 55 start = _manager.alloc_from_back(size); 56 } 57 58 return ZVirtualMemory(start, size); 59 } 60 61 void ZVirtualMemoryManager::free(ZVirtualMemory vmem) { 62 _manager.free(vmem.start(), vmem.size()); 63 }