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 protected:
47 bool _is_dir;
48 time_t _timestamp; // jar/jimage timestamp, 0 if is directory or other
49 long _filesize; // jar/jimage file size, -1 if is directory, -2 if other
50 Array<char>* _name;
51 Array<u1>* _manifest;
52 bool _is_signed;
53
54 public:
55 void init(const char* name, TRAPS);
56 void metaspace_pointers_do(MetaspaceClosure* it);
57 bool validate(bool is_class_path = true);
58
59 // The _timestamp only gets set for jar files and "modules" jimage.
60 bool is_jar_or_bootimage() {
61 return _timestamp != 0;
62 }
63 bool is_dir() { return _is_dir; }
64 bool is_modules_image() { return ClassLoader::is_modules_image(name()); }
65 time_t timestamp() const { return _timestamp; }
66 long filesize() const { return _filesize; }
67 const char* name() const { return _name->data(); }
68 const char* manifest() const {
69 return (_manifest == NULL) ? NULL : (const char*)_manifest->data();
70 }
71 int manifest_size() const {
72 return (_manifest == NULL) ? 0 : _manifest->length();
73 }
74 void set_manifest(Array<u1>* manifest) {
75 _manifest = manifest;
76 }
77 void set_is_signed(bool s) {
78 _is_signed = s;
79 }
80 bool is_signed() {
81 return _is_signed;
82 }
83 };
84
85 class FileMapInfo : public CHeapObj<mtInternal> {
86 private:
87 friend class ManifestStream;
88 friend class VMStructs;
89 enum {
90 _invalid_version = -1,
91 _current_version = 3
92 };
93
94 bool _file_open;
95 int _fd;
96 size_t _file_offset;
97
98 private:
99 static Array<u8>* _shared_path_table;
100 static int _shared_path_table_size;
101 static size_t _shared_path_entry_size;
102 static bool _validating_shared_path_table;
103
104 // FileMapHeader describes the shared space data in the file to be
105 // mapped. This structure gets written to a file. It is not a class, so
106 // that the compilers don't add any compiler-private data to it.
107
108 public:
109 struct FileMapHeaderBase : public CHeapObj<mtClass> { };
110 struct FileMapHeader : FileMapHeaderBase {
111 // Use data() and data_size() to memcopy to/from the FileMapHeader. We need to
112 // avoid read/writing the C++ vtable pointer.
113 static size_t data_size();
114 char* data() {
115 return ((char*)this) + sizeof(FileMapHeaderBase);
116 }
117
118 int _magic; // identify file type.
119 int _crc; // header crc checksum.
120 int _version; // (from enum, above.)
121 size_t _alignment; // how shared archive should be aligned
122 int _obj_alignment; // value of ObjectAlignmentInBytes
123 address _narrow_oop_base; // compressed oop encoding base
124 int _narrow_oop_shift; // compressed oop encoding shift
125 bool _compact_strings; // value of CompactStrings
126 uintx _max_heap_size; // java max heap size during dumping
127 Universe::NARROW_OOP_MODE _narrow_oop_mode; // compressed oop encoding mode
128 int _narrow_klass_shift; // save narrow klass base and shift
129 address _narrow_klass_base;
130 char* _misc_data_patching_start;
131 char* _read_only_tables_start;
132 address _cds_i2i_entry_code_buffers;
133 size_t _cds_i2i_entry_code_buffers_size;
134 size_t _core_spaces_size; // number of bytes allocated by the core spaces
135 // (mc, md, ro, rw and od).
136 struct space_info {
137 int _crc; // crc checksum of the current space
138 size_t _file_offset; // sizeof(this) rounded to vm page size
139 union {
140 char* _base; // copy-on-write base address
141 intx _offset; // offset from the compressed oop encoding base, only used
142 // by archive heap space
143 } _addr;
144 size_t _used; // for setting space top on read
145 bool _read_only; // read only space?
146 bool _allow_exec; // executable code in space?
147 } _space[MetaspaceShared::n_regions];
148
149 // The following fields are all sanity checks for whether this archive
150 // will function correctly with this JVM and the bootclasspath it's
151 // invoked with.
152 char _jvm_ident[JVM_IDENT_MAX]; // identifier for jvm
153
154 // The _paths_misc_info is a variable-size structure that records "miscellaneous"
155 // information during dumping. It is generated and validated by the
156 // SharedPathsMiscInfo class. See SharedPathsMiscInfo.hpp for
157 // detailed description.
158 //
159 // The _paths_misc_info data is stored as a byte array in the archive file header,
160 // immediately after the _header field. This information is used only when
161 // checking the validity of the archive and is deallocated after the archive is loaded.
162 //
163 // Note that the _paths_misc_info does NOT include information for JAR files
164 // that existed during dump time. Their information is stored in _shared_path_table.
165 int _paths_misc_info_size;
166
167 // The following is a table of all the class path entries that were used
168 // during dumping. At run time, we require these files to exist and have the same
169 // size/modification time, or else the archive will refuse to load.
170 //
171 // All of these entries must be JAR files. The dumping process would fail if a non-empty
172 // directory was specified in the classpaths. If an empty directory was specified
173 // it is checked by the _paths_misc_info as described above.
174 //
175 // FIXME -- if JAR files in the tail of the list were specified but not used during dumping,
176 // they should be removed from this table, to save space and to avoid spurious
177 // loading failures during runtime.
178 int _shared_path_table_size;
179 size_t _shared_path_entry_size;
180 Array<u8>* _shared_path_table;
181
182 jshort _app_class_paths_start_index; // Index of first app classpath entry
183 jshort _app_module_paths_start_index; // Index of first module path entry
184 bool _verify_local; // BytecodeVerificationLocal setting
185 bool _verify_remote; // BytecodeVerificationRemote setting
186 bool _has_platform_or_app_classes; // Archive contains app classes
187
188 void set_has_platform_or_app_classes(bool v) {
189 _has_platform_or_app_classes = v;
190 }
191 bool has_platform_or_app_classes() { return _has_platform_or_app_classes; }
192
193 char* region_addr(int idx);
194
195 bool validate();
196 void populate(FileMapInfo* info, size_t alignment);
197 int compute_crc();
198 };
199
200 FileMapHeader * _header;
201
202 const char* _full_path;
203 char* _paths_misc_info;
204
205 static FileMapInfo* _current_info;
206
207 bool init_from_file(int fd);
208 void align_file_position();
209 bool validate_header_impl();
210 static void metaspace_pointers_do(MetaspaceClosure* it);
211
212 public:
213 FileMapInfo();
214 ~FileMapInfo();
215
216 static int current_version() { return _current_version; }
217 int compute_header_crc() { return _header->compute_crc(); }
218 void set_header_crc(int crc) { _header->_crc = crc; }
219 void populate_header(size_t alignment);
220 bool validate_header();
221 void invalidate();
222 int version() { return _header->_version; }
223 size_t alignment() { return _header->_alignment; }
224 Universe::NARROW_OOP_MODE narrow_oop_mode() { return _header->_narrow_oop_mode; }
225 address narrow_oop_base() const { return _header->_narrow_oop_base; }
226 int narrow_oop_shift() const { return _header->_narrow_oop_shift; }
227 uintx max_heap_size() const { return _header->_max_heap_size; }
228 address narrow_klass_base() const { return _header->_narrow_klass_base; }
229 int narrow_klass_shift() const { return _header->_narrow_klass_shift; }
230 struct FileMapHeader* header() { return _header; }
231 char* misc_data_patching_start() { return _header->_misc_data_patching_start; }
232 void set_misc_data_patching_start(char* p) { _header->_misc_data_patching_start = p; }
233 char* read_only_tables_start() { return _header->_read_only_tables_start; }
234 void set_read_only_tables_start(char* p) { _header->_read_only_tables_start = p; }
235
236 address cds_i2i_entry_code_buffers() {
237 return _header->_cds_i2i_entry_code_buffers;
238 }
239 void set_cds_i2i_entry_code_buffers(address addr) {
240 _header->_cds_i2i_entry_code_buffers = addr;
241 }
242 size_t cds_i2i_entry_code_buffers_size() {
243 return _header->_cds_i2i_entry_code_buffers_size;
244 }
245 void set_cds_i2i_entry_code_buffers_size(size_t s) {
246 _header->_cds_i2i_entry_code_buffers_size = s;
247 }
248 void set_core_spaces_size(size_t s) { _header->_core_spaces_size = s; }
249 size_t core_spaces_size() { return _header->_core_spaces_size; }
250
251 static FileMapInfo* current_info() {
252 CDS_ONLY(return _current_info;)
253 NOT_CDS(return NULL;)
254 }
255
256 static void assert_mark(bool check);
257
258 // File manipulation.
259 bool initialize() NOT_CDS_RETURN_(false);
260 bool open_for_read();
261 void open_for_write();
262 void write_header();
263 void write_region(int region, char* base, size_t size,
264 bool read_only, bool allow_exec);
265 size_t write_archive_heap_regions(GrowableArray<MemRegion> *heap_mem,
266 int first_region_id, int max_num_regions);
267 void write_bytes(const void* buffer, int count);
268 void write_bytes_aligned(const void* buffer, int count);
269 char* map_region(int i, char** top_ret);
270 void map_heap_regions() NOT_CDS_JAVA_HEAP_RETURN;
271 void fixup_mapped_heap_regions() NOT_CDS_JAVA_HEAP_RETURN;
272 void unmap_region(int i);
273 bool verify_region_checksum(int i);
274 void close();
275 bool is_open() { return _file_open; }
276 ReservedSpace reserve_shared_memory();
277
278 // JVM/TI RedefineClasses() support:
279 // Remap the shared readonly space to shared readwrite, private.
280 bool remap_shared_readonly_as_readwrite();
281
282 // Errors.
283 static void fail_stop(const char *msg, ...) ATTRIBUTE_PRINTF(1, 2);
284 static void fail_continue(const char *msg, ...) ATTRIBUTE_PRINTF(1, 2);
285
286 bool is_in_shared_region(const void* p, int idx) NOT_CDS_RETURN_(false);
287 void print_shared_spaces() NOT_CDS_RETURN;
288
289 // Stop CDS sharing and unmap CDS regions.
290 static void stop_sharing_and_unmap(const char* msg);
291
292 static void allocate_shared_path_table();
293 static void check_nonempty_dir_in_shared_path_table();
294 bool validate_shared_path_table();
295 static void update_shared_classpath(ClassPathEntry *cpe, SharedClassPathEntry* ent, TRAPS);
296
297 static SharedClassPathEntry* shared_path(int index) {
298 if (index < 0) {
299 return NULL;
300 }
301 assert(index < _shared_path_table_size, "sanity");
302 char* p = (char*)_shared_path_table->data();
303 p += _shared_path_entry_size * index;
304 return (SharedClassPathEntry*)p;
305 }
306
307 static const char* shared_path_name(int index) {
308 assert(index >= 0, "Sanity");
309 return shared_path(index)->name();
310 }
311
312 static int get_number_of_shared_paths() {
313 return _shared_path_table_size;
314 }
315
316 private:
317 bool map_heap_data(MemRegion **heap_mem, int first, int max, int* num,
318 bool is_open = false) NOT_CDS_JAVA_HEAP_RETURN_(false);
319 bool verify_mapped_heap_regions(int first, int num) NOT_CDS_JAVA_HEAP_RETURN_(false);
320 void dealloc_archive_heap_regions(MemRegion* regions, int num) NOT_CDS_JAVA_HEAP_RETURN;
321 };
322
323 #endif // SHARE_VM_MEMORY_FILEMAP_HPP