1 /* 2 * Copyright (c) 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 OS_WINDOWS_GC_Z_ZMAPPER_WINDOWS_HPP 25 #define OS_WINDOWS_GC_Z_ZMAPPER_WINDOWS_HPP 26 27 #include "memory/allocation.hpp" 28 #include "utilities/globalDefinitions.hpp" 29 30 #include <Windows.h> 31 32 class ZMapper : public AllStatic { 33 private: 34 // Create paging file mapping 35 static HANDLE create_paging_file_mapping(size_t size); 36 37 // Commit paging file mapping 38 static bool commit_paging_file_mapping(HANDLE file_handle, uintptr_t file_offset, size_t size); 39 40 // Map a view anywhere without a placeholder 41 static uintptr_t map_view_no_placeholder(HANDLE file_handle, uintptr_t file_offset, size_t size); 42 43 // Unmap a view without preserving a placeholder 44 static void unmap_view_no_placeholder(uintptr_t addr, size_t size); 45 46 // Commit memory covering the given virtual address range 47 static uintptr_t commit(uintptr_t addr, size_t size); 48 49 public: 50 // Reserve memory with a placeholder 51 static uintptr_t reserve(uintptr_t addr, size_t size); 52 53 // Unreserve memory 54 static void unreserve(uintptr_t addr, size_t size); 55 56 // Create and commit paging file mapping 57 static HANDLE create_and_commit_paging_file_mapping(size_t size); 58 59 // Close paging file mapping 60 static void close_paging_file_mapping(HANDLE file_handle); 61 62 // Split a placeholder 63 // 64 // A view can only replace an entire placeholder, so placeholders need to be 65 // split and coalesced to be the exact size of the new views. 66 // [addr, addr + size) needs to be a proper sub-placeholder of an existing 67 // placeholder. 68 static void split_placeholder(uintptr_t addr, size_t size); 69 70 // Coalesce a placeholder 71 // 72 // [addr, addr + size) is the new placeholder. A sub-placeholder needs to 73 // exist within that range. 74 static void coalesce_placeholders(uintptr_t addr, size_t size); 75 76 // Map a view of the file handle and replace the placeholder covering the 77 // given virtual address range 78 static void map_view_replace_placeholder(HANDLE file_handle, uintptr_t file_offset, uintptr_t addr, size_t size); 79 80 // Unmap the view and reinstate a placeholder covering the given virtual 81 // address range 82 static void unmap_view_preserve_placeholder(uintptr_t addr, size_t size); 83 }; 84 85 #endif // OS_WINDOWS_GC_Z_ZMAPPER_WINDOWS_HPP