1 /*
2 * Copyright (c) 2018, 2024, 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
25 #ifndef SHARE_CDS_ARCHIVEHEAPLOADER_HPP
26 #define SHARE_CDS_ARCHIVEHEAPLOADER_HPP
27
28 #include "cds/filemap.hpp"
29 #include "gc/shared/gc_globals.hpp"
30 #include "memory/allocation.hpp"
31 #include "memory/allStatic.hpp"
32 #include "memory/memRegion.hpp"
33 #include "oops/oopsHierarchy.hpp"
34 #include "runtime/globals.hpp"
35 #include "utilities/bitMap.hpp"
36 #include "utilities/macros.hpp"
37
38 class FileMapInfo;
39 struct LoadedArchiveHeapRegion;
40
41 class ArchiveHeapLoader : AllStatic {
42 public:
43 // At runtime, the heap region in the CDS archive can be used in two different ways,
44 // depending on the GC type:
45 // - Mapped: (G1 only) the region is directly mapped into the Java heap
46 // - Loaded: At VM start-up, the objects in the heap region are copied into the
47 // Java heap. This is easier to implement than mapping but
48 // slightly less efficient, as the embedded pointers need to be relocated.
49 static bool can_use() { return can_map() || can_load(); }
50
51 // Can this VM map archived heap region? Currently only G1+compressed{oops,cp}
52 static bool can_map() {
53 CDS_JAVA_HEAP_ONLY(return (UseG1GC && UseCompressedClassPointers);)
54 NOT_CDS_JAVA_HEAP(return false;)
55 }
56
57 // Can this VM load the objects from archived heap region into the heap at start-up?
58 static bool can_load() NOT_CDS_JAVA_HEAP_RETURN_(false);
59 static void finish_initialization() NOT_CDS_JAVA_HEAP_RETURN;
60 static bool is_loaded() {
61 CDS_JAVA_HEAP_ONLY(return _is_loaded;)
62 NOT_CDS_JAVA_HEAP(return false;)
63 }
64
65 static bool is_in_use() {
66 return is_loaded() || is_mapped();
67 }
68
69 static ptrdiff_t mapped_heap_delta() {
70 CDS_JAVA_HEAP_ONLY(assert(!is_loaded(), "must be"));
71 CDS_JAVA_HEAP_ONLY(assert(_mapped_heap_relocation_initialized, "must be"));
72 CDS_JAVA_HEAP_ONLY(return _mapped_heap_delta;)
73 NOT_CDS_JAVA_HEAP_RETURN_(0L);
74 }
75
76 static void set_mapped() {
77 CDS_JAVA_HEAP_ONLY(_is_mapped = true;)
78 NOT_CDS_JAVA_HEAP_RETURN;
79 }
80 static bool is_mapped() {
81 CDS_JAVA_HEAP_ONLY(return _is_mapped;)
82 NOT_CDS_JAVA_HEAP_RETURN_(false);
83 }
84
85 // NarrowOops stored in the CDS archive may use a different encoding scheme
86 // than CompressedOops::{base,shift} -- see FileMapInfo::map_heap_region_impl.
87 // To decode them, do not use CompressedOops::decode_not_null. Use this
88 // function instead.
89 inline static oop decode_from_archive(narrowOop v) NOT_CDS_JAVA_HEAP_RETURN_(nullptr);
90
91 // More efficient version, but works only when ArchiveHeap is mapped.
92 inline static oop decode_from_mapped_archive(narrowOop v) NOT_CDS_JAVA_HEAP_RETURN_(nullptr);
93
94 static void patch_compressed_embedded_pointers(BitMapView bm,
95 FileMapInfo* info,
96 MemRegion region) NOT_CDS_JAVA_HEAP_RETURN;
97
98 static void patch_embedded_pointers(FileMapInfo* info,
99 MemRegion region, address oopmap,
100 size_t oopmap_size_in_bits) NOT_CDS_JAVA_HEAP_RETURN;
101
102 static void fixup_region() NOT_CDS_JAVA_HEAP_RETURN;
103
104 #if INCLUDE_CDS_JAVA_HEAP
105 static void init_mapped_heap_info(address mapped_heap_bottom, ptrdiff_t delta, int dumptime_oop_shift);
106 private:
107 static bool _is_mapped;
108 static bool _is_loaded;
109
110 // Support for loaded archived heap. These are cached values from
111 // LoadedArchiveHeapRegion's.
112 static uintptr_t _dumptime_base;
113 static uintptr_t _dumptime_top;
114 static intx _runtime_offset;
115
116 static uintptr_t _loaded_heap_bottom;
117 static uintptr_t _loaded_heap_top;
118 static bool _loading_failed;
119
120 // UseCompressedOops only: Used by decode_from_archive
121 static bool _narrow_oop_base_initialized;
122 static address _narrow_oop_base;
123 static int _narrow_oop_shift;
124
125 // is_mapped() only: the mapped address of each region is offset by this amount from
126 // their requested address.
127 static uintptr_t _mapped_heap_bottom;
128 static ptrdiff_t _mapped_heap_delta;
129 static bool _mapped_heap_relocation_initialized;
130
131 static void init_narrow_oop_decoding(address base, int shift);
132 static bool init_loaded_region(FileMapInfo* mapinfo, LoadedArchiveHeapRegion* loaded_region,
133 MemRegion& archive_space);
134 static bool load_heap_region_impl(FileMapInfo* mapinfo, LoadedArchiveHeapRegion* loaded_region, uintptr_t buffer);
135 static void init_loaded_heap_relocation(LoadedArchiveHeapRegion* reloc_info);
136 static void patch_native_pointers();
137 static void finish_loaded_heap();
138 static void verify_loaded_heap();
139 static void fill_failed_loaded_heap();
140
141 static bool is_in_loaded_heap(uintptr_t o) {
142 return (_loaded_heap_bottom <= o && o < _loaded_heap_top);
143 }
144
145 template<bool IS_MAPPED>
146 inline static oop decode_from_archive_impl(narrowOop v) NOT_CDS_JAVA_HEAP_RETURN_(nullptr);
147
148 class PatchLoadedRegionPointers;
149 class PatchUncompressedLoadedRegionPointers;
150
151 public:
152
153 static bool load_heap_region(FileMapInfo* mapinfo);
154 static void assert_in_loaded_heap(uintptr_t o) {
155 assert(is_in_loaded_heap(o), "must be");
156 }
157 static oop oop_from_offset(int offset);
158 #endif // INCLUDE_CDS_JAVA_HEAP
159
160 };
161
162 #endif // SHARE_CDS_ARCHIVEHEAPLOADER_HPP