1 /*
2 * Copyright (c) 2019, 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.
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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.
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23 */
24
25 #ifndef SHARE_CDS_ARCHIVEUTILS_HPP
26 #define SHARE_CDS_ARCHIVEUTILS_HPP
27
28 #include "cds/cds_globals.hpp"
29 #include "cds/serializeClosure.hpp"
30 #include "logging/log.hpp"
31 #include "memory/metaspace.hpp"
32 #include "memory/virtualspace.hpp"
33 #include "utilities/bitMap.hpp"
34 #include "utilities/exceptions.hpp"
35 #include "utilities/macros.hpp"
36
37 class BootstrapInfo;
38 class ReservedSpace;
39 class VirtualSpace;
40
41 template<class E> class Array;
42 template<class E> class GrowableArray;
43
44 // ArchivePtrMarker is used to mark the location of pointers embedded in a CDS archive. E.g., when an
45 // InstanceKlass k is dumped, we mark the location of the k->_name pointer by effectively calling
46 // mark_pointer(/*ptr_loc=*/&k->_name). It's required that (_prt_base <= ptr_loc < _ptr_end). _ptr_base is
47 // fixed, but _ptr_end can be expanded as more objects are dumped.
48 class ArchivePtrMarker : AllStatic {
49 static CHeapBitMap* _ptrmap;
50 static CHeapBitMap* _rw_ptrmap;
51 static CHeapBitMap* _ro_ptrmap;
52 static CHeapBitMap* _cc_ptrmap;
53 static VirtualSpace* _vs;
54
55 // Once _ptrmap is compacted, we don't allow bit marking anymore. This is to
56 // avoid unintentional copy operations after the bitmap has been finalized and written.
57 static bool _compacted;
58
59 static address* ptr_base() { return (address*)_vs->low(); } // committed lower bound (inclusive)
60 static address* ptr_end() { return (address*)_vs->high(); } // committed upper bound (exclusive)
61
62 public:
63 static void initialize(CHeapBitMap* ptrmap, VirtualSpace* vs);
64 static void initialize_rw_ro_cc_maps(CHeapBitMap* rw_ptrmap, CHeapBitMap* ro_ptrmap, CHeapBitMap* cc_ptrmap);
65 static void mark_pointer(address* ptr_loc);
66 static void clear_pointer(address* ptr_loc);
67 static void compact(address relocatable_base, address relocatable_end);
68 static void compact(size_t max_non_null_offset);
69
70 template <typename T>
71 static void mark_pointer(T* ptr_loc) {
72 mark_pointer((address*)ptr_loc);
73 }
74
75 template <typename T>
76 static void set_and_mark_pointer(T* ptr_loc, T ptr_value) {
77 *ptr_loc = ptr_value;
78 mark_pointer(ptr_loc);
79 }
80
81 static CHeapBitMap* ptrmap() {
82 return _ptrmap;
83 }
84
85 static CHeapBitMap* rw_ptrmap() {
86 return _rw_ptrmap;
87 }
88
89 static CHeapBitMap* ro_ptrmap() {
90 return _ro_ptrmap;
91 }
92
93 static CHeapBitMap* cc_ptrmap() {
94 return _cc_ptrmap;
95 }
96
97 static void reset_map_and_vs() {
98 _ptrmap = nullptr;
99 _rw_ptrmap = nullptr;
100 _ro_ptrmap = nullptr;
101 _cc_ptrmap = nullptr;
102 _vs = nullptr;
103 }
104 };
105
106 // SharedDataRelocator is used to shift pointers in the CDS archive.
107 //
108 // The CDS archive is basically a contiguous block of memory (divided into several regions)
109 // that contains multiple objects. The objects may contain direct pointers that point to other objects
110 // within the archive (e.g., InstanceKlass::_name points to a Symbol in the archive). During dumping, we
111 // built a bitmap that marks the locations of all these pointers (using ArchivePtrMarker, see comments above).
112 //
113 // The contents of the archive assumes that it’s mapped at the default SharedBaseAddress (e.g. 0x800000000).
114 // If the archive ends up being mapped at a different address (e.g. 0x810000000), SharedDataRelocator
115 // is used to shift each marked pointer by a delta (0x10000000 in this example), so that it points to
116 // the actually mapped location of the target object.
117 class SharedDataRelocator: public BitMapClosure {
118 // for all (address** p), where (is_marked(p) && _patch_base <= p && p < _patch_end) { *p += delta; }
119
120 // Patch all pointers within this region that are marked.
121 address* _patch_base;
122 address* _patch_end;
123
124 // Before patching, all pointers must point to this region.
125 address _valid_old_base;
126 address _valid_old_end;
127
128 // After patching, all pointers must point to this region.
129 address _valid_new_base;
130 address _valid_new_end;
131
132 // How much to relocate for each pointer.
133 intx _delta;
134
135 public:
136 SharedDataRelocator(address* patch_base, address* patch_end,
137 address valid_old_base, address valid_old_end,
138 address valid_new_base, address valid_new_end, intx delta) :
139 _patch_base(patch_base), _patch_end(patch_end),
140 _valid_old_base(valid_old_base), _valid_old_end(valid_old_end),
141 _valid_new_base(valid_new_base), _valid_new_end(valid_new_end),
142 _delta(delta) {
143 log_debug(cds, reloc)("SharedDataRelocator::_patch_base = " PTR_FORMAT, p2i(_patch_base));
144 log_debug(cds, reloc)("SharedDataRelocator::_patch_end = " PTR_FORMAT, p2i(_patch_end));
145 log_debug(cds, reloc)("SharedDataRelocator::_valid_old_base = " PTR_FORMAT, p2i(_valid_old_base));
146 log_debug(cds, reloc)("SharedDataRelocator::_valid_old_end = " PTR_FORMAT, p2i(_valid_old_end));
147 log_debug(cds, reloc)("SharedDataRelocator::_valid_new_base = " PTR_FORMAT, p2i(_valid_new_base));
148 log_debug(cds, reloc)("SharedDataRelocator::_valid_new_end = " PTR_FORMAT, p2i(_valid_new_end));
149 }
150
151 bool do_bit(size_t offset);
152 };
153
154 class DumpRegion {
155 private:
156 const char* _name;
157 char* _base;
158 char* _top;
159 char* _end;
160 uintx _max_delta;
161 bool _is_packed;
162 ReservedSpace* _rs;
163 VirtualSpace* _vs;
164
165 void commit_to(char* newtop);
166
167 public:
168 DumpRegion(const char* name, uintx max_delta = 0)
169 : _name(name), _base(nullptr), _top(nullptr), _end(nullptr),
170 _max_delta(max_delta), _is_packed(false),
171 _rs(NULL), _vs(NULL) {}
172
173 char* expand_top_to(char* newtop);
174 char* allocate(size_t num_bytes, size_t alignment = 0);
175
176 void append_intptr_t(intptr_t n, bool need_to_mark = false) NOT_CDS_RETURN;
177
178 char* base() const { return _base; }
179 char* top() const { return _top; }
180 char* end() const { return _end; }
181 size_t reserved() const { return _end - _base; }
182 size_t used() const { return _top - _base; }
183 bool is_packed() const { return _is_packed; }
184 bool is_allocatable() const {
185 return !is_packed() && _base != nullptr;
186 }
187
188 void print(size_t total_bytes) const;
189 void print_out_of_space_msg(const char* failing_region, size_t needed_bytes);
190
191 void init(ReservedSpace* rs, VirtualSpace* vs);
192
193 void pack(DumpRegion* next = nullptr);
194
195 bool contains(char* p) {
196 return base() <= p && p < top();
197 }
198 };
199
200 // Closure for serializing initialization data out to a data area to be
201 // written to the shared file.
202
203 class WriteClosure : public SerializeClosure {
204 private:
205 DumpRegion* _dump_region;
206
207 public:
208 WriteClosure(DumpRegion* r) {
209 _dump_region = r;
210 }
211
212 void do_ptr(void** p);
213
214 void do_u4(u4* p) {
215 _dump_region->append_intptr_t((intptr_t)(*p));
216 }
217
218 void do_int(int* p) {
219 _dump_region->append_intptr_t((intptr_t)(*p));
220 }
221
222 void do_bool(bool *p) {
223 _dump_region->append_intptr_t((intptr_t)(*p));
224 }
225
226 void do_tag(int tag) {
227 _dump_region->append_intptr_t((intptr_t)tag);
228 }
229
230 char* region_top() {
231 return _dump_region->top();
232 }
233
234 bool reading() const { return false; }
235 };
236
237 // Closure for serializing initialization data in from a data area
238 // (ptr_array) read from the shared file.
239
240 class ReadClosure : public SerializeClosure {
241 private:
242 intptr_t** _ptr_array;
243 intptr_t _base_address;
244 inline intptr_t nextPtr() {
245 return *(*_ptr_array)++;
246 }
247
248 public:
249 ReadClosure(intptr_t** ptr_array, intptr_t base_address) :
250 _ptr_array(ptr_array), _base_address(base_address) {}
251
252 void do_ptr(void** p);
253 void do_u4(u4* p);
254 void do_int(int* p);
255 void do_bool(bool *p);
256 void do_tag(int tag);
257 bool reading() const { return true; }
258 char* region_top() { return nullptr; }
259 };
260
261 class ArchiveUtils {
262 public:
263 static const uintx MAX_SHARED_DELTA = 0x7FFFFFFF;
264 static void log_to_classlist(BootstrapInfo* bootstrap_specifier, TRAPS) NOT_CDS_RETURN;
265 static bool has_aot_initialized_mirror(InstanceKlass* src_ik);
266 template <typename T> static Array<T>* archive_array(GrowableArray<T>* tmp_array);
267
268 static const char* builtin_loader_name_or_null(oop loader); // "boot", "platform", "app", or nullptr
269 static const char* builtin_loader_name(oop loader); // "boot", "platform", or "app". Asserts if not a built-in-loader.
270
271 static bool builtin_loader_from_type(const char* loader_type, oop* value_ret);
272 static oop builtin_loader_from_type(int loader_type);
273
274 // offset must represent an object of type T in the mapped shared space. Return
275 // a direct pointer to this object.
276 template <typename T> T static from_offset(u4 offset) {
277 T p = (T)(SharedBaseAddress + offset);
278 assert(Metaspace::is_in_shared_metaspace(p), "must be");
279 return p;
280 }
281
282 // p must be an archived object. Get its offset from SharedBaseAddress
283 template <typename T> static u4 to_offset(T p) {
284 uintx pn = (uintx)p;
285 uintx base = (uintx)SharedBaseAddress;
286 assert(Metaspace::is_in_shared_metaspace(p), "must be");
287 assert(pn > base, "sanity"); // No valid object is stored at 0 offset from SharedBaseAddress
288 uintx offset = pn - base;
289 assert(offset <= MAX_SHARED_DELTA, "range check");
290 return static_cast<u4>(offset);
291 }
292 };
293
294 class HeapRootSegments {
295 private:
296 size_t _base_offset;
297 size_t _count;
298 int _roots_count;
299 int _max_size_in_bytes;
300 int _max_size_in_elems;
301
302 public:
303 size_t base_offset() { return _base_offset; }
304 size_t count() { return _count; }
305 int roots_count() { return _roots_count; }
306 int max_size_in_bytes() { return _max_size_in_bytes; }
307 int max_size_in_elems() { return _max_size_in_elems; }
308
309 size_t size_in_bytes(size_t seg_idx);
310 int size_in_elems(size_t seg_idx);
311 size_t segment_offset(size_t seg_idx);
312
313 // Trivial copy assignments are allowed to copy the entire object representation.
314 // We also inline this class into archive header. Therefore, it is important to make
315 // sure any gaps in object representation are initialized to zeroes. This is why
316 // constructors memset before doing field assignments.
317 HeapRootSegments() {
318 memset(this, 0, sizeof(*this));
319 }
320 HeapRootSegments(size_t base_offset, int roots_count, int max_size_in_bytes, int max_size_in_elems) {
321 memset(this, 0, sizeof(*this));
322 _base_offset = base_offset;
323 _count = (roots_count + max_size_in_elems - 1) / max_size_in_elems;
324 _roots_count = roots_count;
325 _max_size_in_bytes = max_size_in_bytes;
326 _max_size_in_elems = max_size_in_elems;
327 }
328
329 // This class is trivially copyable and assignable.
330 HeapRootSegments(const HeapRootSegments&) = default;
331 HeapRootSegments& operator=(const HeapRootSegments&) = default;
332 };
333
334 #endif // SHARE_CDS_ARCHIVEUTILS_HPP