1 /*
2 * Copyright (c) 2003, 2018, 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_VM_MEMORY_FILEMAP_HPP
26 #define SHARE_VM_MEMORY_FILEMAP_HPP
27
28 #include "classfile/classLoader.hpp"
29 #include "memory/metaspaceShared.hpp"
30 #include "memory/metaspace.hpp"
31 #include "memory/universe.hpp"
32 #include "utilities/align.hpp"
33
34 // Layout of the file:
35 // header: dump of archive instance plus versioning info, datestamp, etc.
36 // [magic # = 0xF00BABA2]
37 // ... padding to align on page-boundary
38 // read-write space
39 // read-only space
40 // misc data (block offset table, string table, symbols, dictionary, etc.)
41 // tag(666)
42
43 static const int JVM_IDENT_MAX = 256;
44
45 class SharedClassPathEntry {
46 enum {
47 modules_image_entry,
48 jar_entry,
49 signed_jar_entry,
50 dir_entry,
51 unknown_entry
52 };
53 protected:
54 u1 _type;
55 time_t _timestamp; // jar timestamp, 0 if is directory, modules image or other
56 long _filesize; // jar/jimage file size, -1 if is directory, -2 if other
57 Array<char>* _name;
58 Array<u1>* _manifest;
59
60 public:
61 void init(const char* name, bool is_modules_image, TRAPS);
62 void metaspace_pointers_do(MetaspaceClosure* it);
63 bool validate(bool is_class_path = true);
64
65 // The _timestamp only gets set for jar files.
66 bool has_timestamp() {
67 return _timestamp != 0;
68 }
69 bool is_dir() { return _type == dir_entry; }
70 bool is_modules_image() { return _type == modules_image_entry; }
71 bool is_jar() { return _type == jar_entry; }
72 bool is_signed() { return _type == signed_jar_entry; }
73 void set_is_signed() {
74 _type = signed_jar_entry;
75 }
76 time_t timestamp() const { return _timestamp; }
77 long filesize() const { return _filesize; }
78 const char* name() const { return _name->data(); }
79 const char* manifest() const {
80 return (_manifest == NULL) ? NULL : (const char*)_manifest->data();
81 }
82 int manifest_size() const {
83 return (_manifest == NULL) ? 0 : _manifest->length();
84 }
85 void set_manifest(Array<u1>* manifest) {
86 _manifest = manifest;
87 }
88 };
89
90 struct ArchiveHeapOopmapInfo {
91 address _oopmap; // bitmap for relocating embedded oops
92 size_t _oopmap_size_in_bits;
93 };
94
95 class FileMapInfo : public CHeapObj<mtInternal> {
96 private:
97 friend class ManifestStream;
98 friend class VMStructs;
99 enum {
100 _invalid_version = -1,
101 _current_version = 4
102 };
103
104 bool _file_open;
105 int _fd;
106 size_t _file_offset;
107
108 private:
109 static Array<u8>* _shared_path_table;
110 static int _shared_path_table_size;
111 static size_t _shared_path_entry_size;
112 static bool _validating_shared_path_table;
113
114 // FileMapHeader describes the shared space data in the file to be
115 // mapped. This structure gets written to a file. It is not a class, so
116 // that the compilers don't add any compiler-private data to it.
117
118 public:
119 struct FileMapHeaderBase : public CHeapObj<mtClass> {
120 // Need to put something here. Otherwise, in product build, because CHeapObj has no virtual
121 // methods, we would get sizeof(FileMapHeaderBase) == 1 with gcc.
122 intx _dummy;
123 };
124
125 struct FileMapHeader : FileMapHeaderBase {
126 // Use data() and data_size() to memcopy to/from the FileMapHeader. We need to
127 // avoid read/writing the C++ vtable pointer.
128 static size_t data_size() {
129 return sizeof(FileMapHeader) - sizeof(FileMapInfo::FileMapHeaderBase);
130 }
131 char* data() {
132 return ((char*)this) + sizeof(FileMapHeaderBase);
133 }
134 FileMapHeader() {
135 memset(data(), 0, data_size());
136 }
137 int _magic; // identify file type.
138 int _crc; // header crc checksum.
139 int _version; // (from enum, above.)
140 size_t _alignment; // how shared archive should be aligned
141 int _obj_alignment; // value of ObjectAlignmentInBytes
142 address _narrow_oop_base; // compressed oop encoding base
143 int _narrow_oop_shift; // compressed oop encoding shift
144 bool _compact_strings; // value of CompactStrings
145 uintx _max_heap_size; // java max heap size during dumping
146 Universe::NARROW_OOP_MODE _narrow_oop_mode; // compressed oop encoding mode
147 int _narrow_klass_shift; // save narrow klass base and shift
148 address _narrow_klass_base;
149 char* _misc_data_patching_start;
150 char* _read_only_tables_start;
151 address _cds_i2i_entry_code_buffers;
152 size_t _cds_i2i_entry_code_buffers_size;
153 size_t _core_spaces_size; // number of bytes allocated by the core spaces
154 // (mc, md, ro, rw and od).
155 MemRegion _heap_reserved; // reserved region for the entire heap at dump time.
156 struct space_info {
157 int _crc; // crc checksum of the current space
158 size_t _file_offset; // sizeof(this) rounded to vm page size
159 union {
160 char* _base; // copy-on-write base address
161 intx _offset; // offset from the compressed oop encoding base, only used
162 // by archive heap space
163 } _addr;
164 size_t _used; // for setting space top on read
165 bool _read_only; // read only space?
166 bool _allow_exec; // executable code in space?
167 address _oopmap; // bitmap for relocating embedded oops
168 size_t _oopmap_size_in_bits;
169 narrowOop offset() {
170 return (narrowOop)_addr._offset;
171 }
172
173 // The starting address, as calculated with CompressedOop::decode_non_null()
174 address start_address_with_current_oop_encoding_mode() {
175 return decode_start_address(true);
176 }
177
178 // The starting address, as calculated with HeapShared::decode_with_archived_oop_encoding_mode()
179 address start_address_with_archived_oop_encoding_mode() {
180 return decode_start_address(false);
181 }
182 private:
183 address decode_start_address(bool with_current_oop_encoding_mode);
184 } _space[MetaspaceShared::n_regions];
185
186 // The following fields are all sanity checks for whether this archive
187 // will function correctly with this JVM and the bootclasspath it's
188 // invoked with.
189 char _jvm_ident[JVM_IDENT_MAX]; // identifier for jvm
190
191 // The _paths_misc_info is a variable-size structure that records "miscellaneous"
192 // information during dumping. It is generated and validated by the
193 // SharedPathsMiscInfo class. See SharedPathsMiscInfo.hpp for
194 // detailed description.
195 //
196 // The _paths_misc_info data is stored as a byte array in the archive file header,
197 // immediately after the _header field. This information is used only when
198 // checking the validity of the archive and is deallocated after the archive is loaded.
199 //
200 // Note that the _paths_misc_info does NOT include information for JAR files
201 // that existed during dump time. Their information is stored in _shared_path_table.
202 int _paths_misc_info_size;
203
204 // The following is a table of all the class path entries that were used
205 // during dumping. At run time, we require these files to exist and have the same
206 // size/modification time, or else the archive will refuse to load.
207 //
208 // All of these entries must be JAR files. The dumping process would fail if a non-empty
209 // directory was specified in the classpaths. If an empty directory was specified
210 // it is checked by the _paths_misc_info as described above.
211 //
212 // FIXME -- if JAR files in the tail of the list were specified but not used during dumping,
213 // they should be removed from this table, to save space and to avoid spurious
214 // loading failures during runtime.
215 int _shared_path_table_size;
216 size_t _shared_path_entry_size;
217 Array<u8>* _shared_path_table;
218
219 jshort _app_class_paths_start_index; // Index of first app classpath entry
220 jshort _app_module_paths_start_index; // Index of first module path entry
221 jshort _max_used_path_index; // max path index referenced during CDS dump
222 bool _verify_local; // BytecodeVerificationLocal setting
223 bool _verify_remote; // BytecodeVerificationRemote setting
224 bool _has_platform_or_app_classes; // Archive contains app classes
225
226 void set_has_platform_or_app_classes(bool v) {
227 _has_platform_or_app_classes = v;
228 }
229 bool has_platform_or_app_classes() { return _has_platform_or_app_classes; }
230 jshort max_used_path_index() { return _max_used_path_index; }
231 jshort app_module_paths_start_index() { return _app_module_paths_start_index; }
232
233 char* region_addr(int idx);
234
235 bool validate();
236 void populate(FileMapInfo* info, size_t alignment);
237 int compute_crc();
238 };
239
240 FileMapHeader * _header;
241
242 const char* _full_path;
243 char* _paths_misc_info;
244
245 static FileMapInfo* _current_info;
246 static bool _heap_pointers_need_patching;
247
248 bool init_from_file(int fd);
249 void align_file_position();
250 bool validate_header_impl();
251 static void metaspace_pointers_do(MetaspaceClosure* it);
252
253 public:
254 FileMapInfo();
255 ~FileMapInfo();
256
257 static int current_version() { return _current_version; }
258 int compute_header_crc() { return _header->compute_crc(); }
259 void set_header_crc(int crc) { _header->_crc = crc; }
260 void populate_header(size_t alignment);
261 bool validate_header();
262 void invalidate();
263 int version() { return _header->_version; }
264 size_t alignment() { return _header->_alignment; }
265 Universe::NARROW_OOP_MODE narrow_oop_mode() { return _header->_narrow_oop_mode; }
266 address narrow_oop_base() const { return _header->_narrow_oop_base; }
267 int narrow_oop_shift() const { return _header->_narrow_oop_shift; }
268 uintx max_heap_size() const { return _header->_max_heap_size; }
269 address narrow_klass_base() const { return _header->_narrow_klass_base; }
270 int narrow_klass_shift() const { return _header->_narrow_klass_shift; }
271 struct FileMapHeader* header() { return _header; }
272 char* misc_data_patching_start() { return _header->_misc_data_patching_start; }
273 void set_misc_data_patching_start(char* p) { _header->_misc_data_patching_start = p; }
274 char* read_only_tables_start() { return _header->_read_only_tables_start; }
275 void set_read_only_tables_start(char* p) { _header->_read_only_tables_start = p; }
276
277 address cds_i2i_entry_code_buffers() {
278 return _header->_cds_i2i_entry_code_buffers;
279 }
280 void set_cds_i2i_entry_code_buffers(address addr) {
281 _header->_cds_i2i_entry_code_buffers = addr;
282 }
283 size_t cds_i2i_entry_code_buffers_size() {
284 return _header->_cds_i2i_entry_code_buffers_size;
285 }
286 void set_cds_i2i_entry_code_buffers_size(size_t s) {
287 _header->_cds_i2i_entry_code_buffers_size = s;
288 }
289 void set_core_spaces_size(size_t s) { _header->_core_spaces_size = s; }
290 size_t core_spaces_size() { return _header->_core_spaces_size; }
291
292 static FileMapInfo* current_info() {
293 CDS_ONLY(return _current_info;)
294 NOT_CDS(return NULL;)
295 }
296
297 static void assert_mark(bool check);
298
299 // File manipulation.
300 bool initialize() NOT_CDS_RETURN_(false);
301 bool open_for_read();
302 void open_for_write();
303 void write_header();
304 void write_region(int region, char* base, size_t size,
305 bool read_only, bool allow_exec);
306 size_t write_archive_heap_regions(GrowableArray<MemRegion> *heap_mem,
307 GrowableArray<ArchiveHeapOopmapInfo> *oopmaps,
308 int first_region_id, int max_num_regions);
309 void write_bytes(const void* buffer, int count);
310 void write_bytes_aligned(const void* buffer, int count);
311 char* map_region(int i, char** top_ret);
312 void map_heap_regions_impl() NOT_CDS_JAVA_HEAP_RETURN;
313 void map_heap_regions() NOT_CDS_JAVA_HEAP_RETURN;
314 void fixup_mapped_heap_regions() NOT_CDS_JAVA_HEAP_RETURN;
315 void patch_archived_heap_embedded_pointers() NOT_CDS_JAVA_HEAP_RETURN;
316 void patch_archived_heap_embedded_pointers(MemRegion* ranges, int num_ranges,
317 int first_region_idx) NOT_CDS_JAVA_HEAP_RETURN;
318 bool has_heap_regions() NOT_CDS_JAVA_HEAP_RETURN_(false);
319 MemRegion get_heap_regions_range_with_current_oop_encoding_mode() NOT_CDS_JAVA_HEAP_RETURN_(MemRegion());
320 void unmap_region(int i);
321 bool verify_region_checksum(int i);
322 void close();
323 bool is_open() { return _file_open; }
324 ReservedSpace reserve_shared_memory();
325
326 // JVM/TI RedefineClasses() support:
327 // Remap the shared readonly space to shared readwrite, private.
328 bool remap_shared_readonly_as_readwrite();
329
330 // Errors.
331 static void fail_stop(const char *msg, ...) ATTRIBUTE_PRINTF(1, 2);
332 static void fail_continue(const char *msg, ...) ATTRIBUTE_PRINTF(1, 2);
333
334 bool is_in_shared_region(const void* p, int idx) NOT_CDS_RETURN_(false);
335
336 // Stop CDS sharing and unmap CDS regions.
337 static void stop_sharing_and_unmap(const char* msg);
338
339 static void allocate_shared_path_table();
340 static void check_nonempty_dir_in_shared_path_table();
341 bool validate_shared_path_table();
342 static void update_shared_classpath(ClassPathEntry *cpe, SharedClassPathEntry* ent, TRAPS);
343
344 static SharedClassPathEntry* shared_path(int index) {
345 if (index < 0) {
346 return NULL;
347 }
348 assert(index < _shared_path_table_size, "sanity");
349 char* p = (char*)_shared_path_table->data();
350 p += _shared_path_entry_size * index;
351 return (SharedClassPathEntry*)p;
352 }
353
354 static const char* shared_path_name(int index) {
355 assert(index >= 0, "Sanity");
356 return shared_path(index)->name();
357 }
358
359 static int get_number_of_shared_paths() {
360 return _shared_path_table_size;
361 }
362
363 private:
364 bool map_heap_data(MemRegion **heap_mem, int first, int max, int* num,
365 bool is_open = false) NOT_CDS_JAVA_HEAP_RETURN_(false);
366 bool verify_mapped_heap_regions(int first, int num) NOT_CDS_JAVA_HEAP_RETURN_(false);
367 void dealloc_archive_heap_regions(MemRegion* regions, int num) NOT_CDS_JAVA_HEAP_RETURN;
368
369 FileMapHeader::space_info* space_at(int i) {
370 assert(i >= 0 && i <= MetaspaceShared::last_valid_region, "invalid region");
371 return &_header->_space[i];
372 }
373 };
374
375 #endif // SHARE_VM_MEMORY_FILEMAP_HPP