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 bool _verify_local; // BytecodeVerificationLocal setting
144 bool _verify_remote; // BytecodeVerificationRemote setting
145 bool _has_platform_or_app_classes; // Archive contains app classes
146
147 void set_has_platform_or_app_classes(bool v) {
148 _has_platform_or_app_classes = v;
149 }
150 bool has_platform_or_app_classes() { return _has_platform_or_app_classes; }
151
152 char* region_addr(int idx);
153
154 bool validate();
155 void populate(FileMapInfo* info, size_t alignment);
156 int compute_crc();
157 };
158
159
160 class FileMapInfo : public CHeapObj<mtInternal> {
161 private:
162 friend class ManifestStream;
163 friend class VMStructs;
164 friend struct FileMapHeader;
165
166 bool _file_open;
167 int _fd;
168 size_t _file_offset;
169
170 private:
171 static Array<u8>* _shared_path_table;
172 static int _shared_path_table_size;
173 static size_t _shared_path_entry_size;
174 static bool _validating_shared_path_table;
175
176 // FileMapHeader describes the shared space data in the file to be
177 // mapped. This structure gets written to a file. It is not a class, so
178 // that the compilers don't add any compiler-private data to it.
179
180 public:
181 struct FileMapHeaderBase : public CHeapObj<mtClass> {
182 // Need to put something here. Otherwise, in product build, because CHeapObj has no virtual
183 // methods, we would get sizeof(FileMapHeaderBase) == 1 with gcc.
184 intx _dummy;
185 };
186
187
188 FileMapHeader * _header;
189
190 const char* _full_path;
191 char* _paths_misc_info;
192
193 static FileMapInfo* _current_info;
194
195 bool init_from_file(int fd);
196 void align_file_position();
197 bool validate_header_impl();
198 static void metaspace_pointers_do(MetaspaceClosure* it);
199
200 public:
201 FileMapInfo();
202 ~FileMapInfo();
203
204 int compute_header_crc() { return _header->compute_crc(); }
205 void set_header_crc(int crc) { _header->_crc = crc; }
206 void populate_header(size_t alignment);
207 bool validate_header();
208 void invalidate();
209 int version() { return _header->_version; }
210 size_t alignment() { return _header->_alignment; }
211 Universe::NARROW_OOP_MODE narrow_oop_mode() { return _header->_narrow_oop_mode; }
212 address narrow_oop_base() const { return _header->_narrow_oop_base; }
213 int narrow_oop_shift() const { return _header->_narrow_oop_shift; }
214 uintx max_heap_size() const { return _header->_max_heap_size; }
215 address narrow_klass_base() const { return _header->_narrow_klass_base; }
216 int narrow_klass_shift() const { return _header->_narrow_klass_shift; }
217 struct FileMapHeader* header() { return _header; }
218 char* misc_data_patching_start() { return _header->_misc_data_patching_start; }
219 void set_misc_data_patching_start(char* p) { _header->_misc_data_patching_start = p; }
220 char* read_only_tables_start() { return _header->_read_only_tables_start; }
221 void set_read_only_tables_start(char* p) { _header->_read_only_tables_start = p; }
222
223 address cds_i2i_entry_code_buffers() {
224 return _header->_cds_i2i_entry_code_buffers;
225 }
226 void set_cds_i2i_entry_code_buffers(address addr) {
227 _header->_cds_i2i_entry_code_buffers = addr;
228 }
229 size_t cds_i2i_entry_code_buffers_size() {
230 return _header->_cds_i2i_entry_code_buffers_size;
231 }
232 void set_cds_i2i_entry_code_buffers_size(size_t s) {
233 _header->_cds_i2i_entry_code_buffers_size = s;
234 }
235 void set_core_spaces_size(size_t s) { _header->_core_spaces_size = s; }
236 size_t core_spaces_size() { return _header->_core_spaces_size; }
237
238 static FileMapInfo* current_info() {
239 CDS_ONLY(return _current_info;)
240 NOT_CDS(return NULL;)
241 }
242
243 static void assert_mark(bool check);
244
245 // File manipulation.
246 bool initialize() NOT_CDS_RETURN_(false);
247 bool open_for_read();
248 void open_for_write();
249 void write_header();
250 void write_region(int region, char* base, size_t size,
251 bool read_only, bool allow_exec);
252 size_t write_archive_heap_regions(GrowableArray<MemRegion> *heap_mem,
253 int first_region_id, int max_num_regions);
254 void write_bytes(const void* buffer, size_t count);
255 void write_bytes_aligned(const void* buffer, size_t count);
256 char* map_region(int i, char** top_ret);
257 void map_heap_regions() NOT_CDS_JAVA_HEAP_RETURN;
258 void fixup_mapped_heap_regions() NOT_CDS_JAVA_HEAP_RETURN;
259 void unmap_region(int i);
260 bool verify_region_checksum(int i);
261 void close();
262 bool is_open() { return _file_open; }
263 ReservedSpace reserve_shared_memory();
264
265 // JVM/TI RedefineClasses() support:
266 // Remap the shared readonly space to shared readwrite, private.
267 bool remap_shared_readonly_as_readwrite();
268
269 // Errors.
270 static void fail_stop(const char *msg, ...) ATTRIBUTE_PRINTF(1, 2);
271 static void fail_continue(const char *msg, ...) ATTRIBUTE_PRINTF(1, 2);
272
273 bool is_in_shared_region(const void* p, int idx) NOT_CDS_RETURN_(false);
274 void print_shared_spaces() NOT_CDS_RETURN;
275
276 // Stop CDS sharing and unmap CDS regions.
277 static void stop_sharing_and_unmap(const char* msg);
278
279 static void allocate_shared_path_table();
280 static void check_nonempty_dir_in_shared_path_table();
281 bool validate_shared_path_table();
282 static void update_shared_classpath(ClassPathEntry *cpe, SharedClassPathEntry* ent, TRAPS);
283
284 static SharedClassPathEntry* shared_path(int index) {
285 if (index < 0) {
286 return NULL;
287 }
288 assert(index < _shared_path_table_size, "sanity");
289 char* p = (char*)_shared_path_table->data();
290 p += _shared_path_entry_size * index;
291 return (SharedClassPathEntry*)p;
292 }
293
294 static const char* shared_path_name(int index) {
295 assert(index >= 0, "Sanity");
296 return shared_path(index)->name();
297 }
298
299 static int get_number_of_shared_paths() {
300 return _shared_path_table_size;
301 }
302
303 private:
304 bool map_heap_data(MemRegion **heap_mem, int first, int max, int* num,
305 bool is_open = false) NOT_CDS_JAVA_HEAP_RETURN_(false);
306 bool verify_mapped_heap_regions(int first, int num) NOT_CDS_JAVA_HEAP_RETURN_(false);
307 void dealloc_archive_heap_regions(MemRegion* regions, int num) NOT_CDS_JAVA_HEAP_RETURN;
308
309 CDSFileMapRegion* space_at(int i) {
310 assert(i >= 0 && i <= NUM_CDS_REGIONS, "invalid region");
311 return &_header->_space[i];
312 }
313 };
314
315 #endif // SHARE_VM_MEMORY_FILEMAP_HPP