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 class FileMapInfo : public CHeapObj<mtInternal> {
91 private:
92 friend class ManifestStream;
93 friend class VMStructs;
94 enum {
95 _invalid_version = -1,
96 _current_version = 3
97 };
98
99 bool _file_open;
100 int _fd;
101 size_t _file_offset;
102
103 private:
104 static Array<u8>* _shared_path_table;
105 static int _shared_path_table_size;
106 static size_t _shared_path_entry_size;
107 static bool _validating_shared_path_table;
108
109 // FileMapHeader describes the shared space data in the file to be
110 // mapped. This structure gets written to a file. It is not a class, so
111 // that the compilers don't add any compiler-private data to it.
112
113 public:
114 struct FileMapHeaderBase : public CHeapObj<mtClass> {
115 // Need to put something here. Otherwise, in product build, because CHeapObj has no virtual
116 // methods, we would get sizeof(FileMapHeaderBase) == 1 with gcc.
117 intx _dummy;
118 };
119 struct FileMapHeader : FileMapHeaderBase {
120 // Use data() and data_size() to memcopy to/from the FileMapHeader. We need to
121 // avoid read/writing the C++ vtable pointer.
122 static size_t data_size() {
123 return sizeof(FileMapHeader) - sizeof(FileMapInfo::FileMapHeaderBase);
124 }
125 char* data() {
126 return ((char*)this) + sizeof(FileMapHeaderBase);
127 }
128
129 int _magic; // identify file type.
130 int _crc; // header crc checksum.
131 int _version; // (from enum, above.)
132 size_t _alignment; // how shared archive should be aligned
133 int _obj_alignment; // value of ObjectAlignmentInBytes
134 address _narrow_oop_base; // compressed oop encoding base
135 int _narrow_oop_shift; // compressed oop encoding shift
136 bool _compact_strings; // value of CompactStrings
137 uintx _max_heap_size; // java max heap size during dumping
138 Universe::NARROW_OOP_MODE _narrow_oop_mode; // compressed oop encoding mode
139 int _narrow_klass_shift; // save narrow klass base and shift
140 address _narrow_klass_base;
141 char* _misc_data_patching_start;
142 char* _read_only_tables_start;
143 address _cds_i2i_entry_code_buffers;
144 size_t _cds_i2i_entry_code_buffers_size;
145 size_t _core_spaces_size; // number of bytes allocated by the core spaces
146 // (mc, md, ro, rw and od).
147 struct space_info {
148 int _crc; // crc checksum of the current space
149 size_t _file_offset; // sizeof(this) rounded to vm page size
150 union {
151 char* _base; // copy-on-write base address
152 intx _offset; // offset from the compressed oop encoding base, only used
153 // by archive heap space
154 } _addr;
155 size_t _used; // for setting space top on read
156 bool _read_only; // read only space?
157 bool _allow_exec; // executable code in space?
158 } _space[MetaspaceShared::n_regions];
159
160 // The following fields are all sanity checks for whether this archive
161 // will function correctly with this JVM and the bootclasspath it's
162 // invoked with.
163 char _jvm_ident[JVM_IDENT_MAX]; // identifier for jvm
164
165 // The _paths_misc_info is a variable-size structure that records "miscellaneous"
166 // information during dumping. It is generated and validated by the
167 // SharedPathsMiscInfo class. See SharedPathsMiscInfo.hpp for
168 // detailed description.
169 //
170 // The _paths_misc_info data is stored as a byte array in the archive file header,
171 // immediately after the _header field. This information is used only when
172 // checking the validity of the archive and is deallocated after the archive is loaded.
173 //
174 // Note that the _paths_misc_info does NOT include information for JAR files
175 // that existed during dump time. Their information is stored in _shared_path_table.
176 int _paths_misc_info_size;
177
178 // The following is a table of all the class path entries that were used
179 // during dumping. At run time, we require these files to exist and have the same
180 // size/modification time, or else the archive will refuse to load.
181 //
182 // All of these entries must be JAR files. The dumping process would fail if a non-empty
183 // directory was specified in the classpaths. If an empty directory was specified
184 // it is checked by the _paths_misc_info as described above.
185 //
186 // FIXME -- if JAR files in the tail of the list were specified but not used during dumping,
187 // they should be removed from this table, to save space and to avoid spurious
188 // loading failures during runtime.
189 int _shared_path_table_size;
190 size_t _shared_path_entry_size;
191 Array<u8>* _shared_path_table;
192
193 jshort _app_class_paths_start_index; // Index of first app classpath entry
194 jshort _app_module_paths_start_index; // Index of first module path entry
195 jshort _max_used_path_index; // max path index referenced during CDS dump
196 bool _verify_local; // BytecodeVerificationLocal setting
197 bool _verify_remote; // BytecodeVerificationRemote setting
198 bool _has_platform_or_app_classes; // Archive contains app classes
199
200 void set_has_platform_or_app_classes(bool v) {
201 _has_platform_or_app_classes = v;
202 }
203 bool has_platform_or_app_classes() { return _has_platform_or_app_classes; }
204 jshort max_used_path_index() { return _max_used_path_index; }
205 jshort app_module_paths_start_index() { return _app_module_paths_start_index; }
206
207 char* region_addr(int idx);
208
209 bool validate();
210 void populate(FileMapInfo* info, size_t alignment);
211 int compute_crc();
212 };
213
214 FileMapHeader * _header;
215
216 const char* _full_path;
217 char* _paths_misc_info;
218
219 static FileMapInfo* _current_info;
220
221 bool init_from_file(int fd);
222 void align_file_position();
223 bool validate_header_impl();
224 static void metaspace_pointers_do(MetaspaceClosure* it);
225
226 public:
227 FileMapInfo();
228 ~FileMapInfo();
229
230 static int current_version() { return _current_version; }
231 int compute_header_crc() { return _header->compute_crc(); }
232 void set_header_crc(int crc) { _header->_crc = crc; }
233 void populate_header(size_t alignment);
234 bool validate_header();
235 void invalidate();
236 int version() { return _header->_version; }
237 size_t alignment() { return _header->_alignment; }
238 Universe::NARROW_OOP_MODE narrow_oop_mode() { return _header->_narrow_oop_mode; }
239 address narrow_oop_base() const { return _header->_narrow_oop_base; }
240 int narrow_oop_shift() const { return _header->_narrow_oop_shift; }
241 uintx max_heap_size() const { return _header->_max_heap_size; }
242 address narrow_klass_base() const { return _header->_narrow_klass_base; }
243 int narrow_klass_shift() const { return _header->_narrow_klass_shift; }
244 struct FileMapHeader* header() { return _header; }
245 char* misc_data_patching_start() { return _header->_misc_data_patching_start; }
246 void set_misc_data_patching_start(char* p) { _header->_misc_data_patching_start = p; }
247 char* read_only_tables_start() { return _header->_read_only_tables_start; }
248 void set_read_only_tables_start(char* p) { _header->_read_only_tables_start = p; }
249
250 address cds_i2i_entry_code_buffers() {
251 return _header->_cds_i2i_entry_code_buffers;
252 }
253 void set_cds_i2i_entry_code_buffers(address addr) {
254 _header->_cds_i2i_entry_code_buffers = addr;
255 }
256 size_t cds_i2i_entry_code_buffers_size() {
257 return _header->_cds_i2i_entry_code_buffers_size;
258 }
259 void set_cds_i2i_entry_code_buffers_size(size_t s) {
260 _header->_cds_i2i_entry_code_buffers_size = s;
261 }
262 void set_core_spaces_size(size_t s) { _header->_core_spaces_size = s; }
263 size_t core_spaces_size() { return _header->_core_spaces_size; }
264
265 static FileMapInfo* current_info() {
266 CDS_ONLY(return _current_info;)
267 NOT_CDS(return NULL;)
268 }
269
270 static void assert_mark(bool check);
271
272 // File manipulation.
273 bool initialize() NOT_CDS_RETURN_(false);
274 bool open_for_read();
275 void open_for_write();
276 void write_header();
277 void write_region(int region, char* base, size_t size,
278 bool read_only, bool allow_exec);
279 size_t write_archive_heap_regions(GrowableArray<MemRegion> *heap_mem,
280 int first_region_id, int max_num_regions);
281 void write_bytes(const void* buffer, int count);
282 void write_bytes_aligned(const void* buffer, int count);
283 char* map_region(int i, char** top_ret);
284 void map_heap_regions() NOT_CDS_JAVA_HEAP_RETURN;
285 void fixup_mapped_heap_regions() NOT_CDS_JAVA_HEAP_RETURN;
286 void unmap_region(int i);
287 bool verify_region_checksum(int i);
288 void close();
289 bool is_open() { return _file_open; }
290 ReservedSpace reserve_shared_memory();
291
292 // JVM/TI RedefineClasses() support:
293 // Remap the shared readonly space to shared readwrite, private.
294 bool remap_shared_readonly_as_readwrite();
295
296 // Errors.
297 static void fail_stop(const char *msg, ...) ATTRIBUTE_PRINTF(1, 2);
298 static void fail_continue(const char *msg, ...) ATTRIBUTE_PRINTF(1, 2);
299
300 bool is_in_shared_region(const void* p, int idx) NOT_CDS_RETURN_(false);
301 void print_shared_spaces() NOT_CDS_RETURN;
302
303 // Stop CDS sharing and unmap CDS regions.
304 static void stop_sharing_and_unmap(const char* msg);
305
306 static void allocate_shared_path_table();
307 static void check_nonempty_dir_in_shared_path_table();
308 bool validate_shared_path_table();
309 static void update_shared_classpath(ClassPathEntry *cpe, SharedClassPathEntry* ent, TRAPS);
310
311 static SharedClassPathEntry* shared_path(int index) {
312 if (index < 0) {
313 return NULL;
314 }
315 assert(index < _shared_path_table_size, "sanity");
316 char* p = (char*)_shared_path_table->data();
317 p += _shared_path_entry_size * index;
318 return (SharedClassPathEntry*)p;
319 }
320
321 static const char* shared_path_name(int index) {
322 assert(index >= 0, "Sanity");
323 return shared_path(index)->name();
324 }
325
326 static int get_number_of_shared_paths() {
327 return _shared_path_table_size;
328 }
329
330 private:
331 bool map_heap_data(MemRegion **heap_mem, int first, int max, int* num,
332 bool is_open = false) NOT_CDS_JAVA_HEAP_RETURN_(false);
333 bool verify_mapped_heap_regions(int first, int num) NOT_CDS_JAVA_HEAP_RETURN_(false);
334 void dealloc_archive_heap_regions(MemRegion* regions, int num, bool is_open) NOT_CDS_JAVA_HEAP_RETURN;
335 };
336
337 #endif // SHARE_VM_MEMORY_FILEMAP_HPP