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