1 /*
2 * Copyright (c) 2003, 2024, 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 #include "precompiled.hpp"
26 #include "cds/archiveBuilder.hpp"
27 #include "cds/archiveHeapLoader.inline.hpp"
28 #include "cds/archiveHeapWriter.hpp"
29 #include "cds/archiveUtils.inline.hpp"
30 #include "cds/cds_globals.hpp"
31 #include "cds/cdsConfig.hpp"
32 #include "cds/dynamicArchive.hpp"
33 #include "cds/filemap.hpp"
34 #include "cds/heapShared.hpp"
35 #include "cds/metaspaceShared.hpp"
36 #include "classfile/altHashing.hpp"
37 #include "classfile/classFileStream.hpp"
38 #include "classfile/classLoader.hpp"
39 #include "classfile/classLoader.inline.hpp"
40 #include "classfile/classLoaderData.inline.hpp"
41 #include "classfile/classLoaderExt.hpp"
42 #include "classfile/symbolTable.hpp"
43 #include "classfile/systemDictionaryShared.hpp"
44 #include "classfile/vmClasses.hpp"
45 #include "classfile/vmSymbols.hpp"
46 #include "jvm.h"
47 #include "logging/log.hpp"
48 #include "logging/logMessage.hpp"
49 #include "logging/logStream.hpp"
50 #include "memory/iterator.inline.hpp"
51 #include "memory/metadataFactory.hpp"
52 #include "memory/metaspaceClosure.hpp"
53 #include "memory/oopFactory.hpp"
54 #include "memory/universe.hpp"
55 #include "nmt/memTracker.hpp"
56 #include "oops/compressedOops.hpp"
57 #include "oops/compressedOops.inline.hpp"
58 #include "oops/objArrayOop.hpp"
59 #include "oops/oop.inline.hpp"
60 #include "prims/jvmtiExport.hpp"
61 #include "runtime/arguments.hpp"
62 #include "runtime/globals_extension.hpp"
63 #include "runtime/java.hpp"
64 #include "runtime/mutexLocker.hpp"
65 #include "runtime/os.hpp"
66 #include "runtime/vm_version.hpp"
67 #include "utilities/align.hpp"
68 #include "utilities/bitMap.inline.hpp"
69 #include "utilities/classpathStream.hpp"
70 #include "utilities/defaultStream.hpp"
71 #include "utilities/ostream.hpp"
72 #if INCLUDE_G1GC
73 #include "gc/g1/g1CollectedHeap.hpp"
74 #include "gc/g1/g1HeapRegion.hpp"
75 #endif
76
77 # include <sys/stat.h>
78 # include <errno.h>
79
80 #ifndef O_BINARY // if defined (Win32) use binary files.
81 #define O_BINARY 0 // otherwise do nothing.
82 #endif
83
84 // Fill in the fileMapInfo structure with data about this VM instance.
85
86 // This method copies the vm version info into header_version. If the version is too
87 // long then a truncated version, which has a hash code appended to it, is copied.
88 //
89 // Using a template enables this method to verify that header_version is an array of
90 // length JVM_IDENT_MAX. This ensures that the code that writes to the CDS file and
91 // the code that reads the CDS file will both use the same size buffer. Hence, will
92 // use identical truncation. This is necessary for matching of truncated versions.
93 template <int N> static void get_header_version(char (&header_version) [N]) {
94 assert(N == JVM_IDENT_MAX, "Bad header_version size");
95
96 const char *vm_version = VM_Version::internal_vm_info_string();
97 const int version_len = (int)strlen(vm_version);
98
99 memset(header_version, 0, JVM_IDENT_MAX);
100
101 if (version_len < (JVM_IDENT_MAX-1)) {
102 strcpy(header_version, vm_version);
103
104 } else {
105 // Get the hash value. Use a static seed because the hash needs to return the same
106 // value over multiple jvm invocations.
107 uint32_t hash = AltHashing::halfsiphash_32(8191, (const uint8_t*)vm_version, version_len);
108
109 // Truncate the ident, saving room for the 8 hex character hash value.
110 strncpy(header_version, vm_version, JVM_IDENT_MAX-9);
111
112 // Append the hash code as eight hex digits.
113 os::snprintf_checked(&header_version[JVM_IDENT_MAX-9], 9, "%08x", hash);
114 header_version[JVM_IDENT_MAX-1] = 0; // Null terminate.
115 }
116
117 assert(header_version[JVM_IDENT_MAX-1] == 0, "must be");
118 }
119
120 FileMapInfo::FileMapInfo(const char* full_path, bool is_static) :
121 _is_static(is_static), _file_open(false), _is_mapped(false), _fd(-1), _file_offset(0),
122 _full_path(full_path), _base_archive_name(nullptr), _header(nullptr) {
123 if (_is_static) {
124 assert(_current_info == nullptr, "must be singleton"); // not thread safe
125 _current_info = this;
126 } else {
127 assert(_dynamic_archive_info == nullptr, "must be singleton"); // not thread safe
128 _dynamic_archive_info = this;
129 }
130 }
131
132 FileMapInfo::~FileMapInfo() {
133 if (_is_static) {
134 assert(_current_info == this, "must be singleton"); // not thread safe
135 _current_info = nullptr;
136 } else {
137 assert(_dynamic_archive_info == this, "must be singleton"); // not thread safe
138 _dynamic_archive_info = nullptr;
139 }
140
141 if (_header != nullptr) {
142 os::free(_header);
143 }
144
145 if (_file_open) {
146 ::close(_fd);
147 }
148 }
149
150 void FileMapInfo::populate_header(size_t core_region_alignment) {
151 assert(_header == nullptr, "Sanity check");
152 size_t c_header_size;
153 size_t header_size;
154 size_t base_archive_name_size = 0;
155 size_t base_archive_name_offset = 0;
156 size_t longest_common_prefix_size = 0;
157 if (is_static()) {
158 c_header_size = sizeof(FileMapHeader);
159 header_size = c_header_size;
160 } else {
161 // dynamic header including base archive name for non-default base archive
162 c_header_size = sizeof(DynamicArchiveHeader);
163 header_size = c_header_size;
164
165 const char* default_base_archive_name = CDSConfig::default_archive_path();
166 const char* current_base_archive_name = CDSConfig::static_archive_path();
167 if (!os::same_files(current_base_archive_name, default_base_archive_name)) {
168 base_archive_name_size = strlen(current_base_archive_name) + 1;
169 header_size += base_archive_name_size;
170 base_archive_name_offset = c_header_size;
171 }
172 }
173 ResourceMark rm;
174 GrowableArray<const char*>* app_cp_array = create_dumptime_app_classpath_array();
175 int len = app_cp_array->length();
176 longest_common_prefix_size = longest_common_app_classpath_prefix_len(len, app_cp_array);
177 _header = (FileMapHeader*)os::malloc(header_size, mtInternal);
178 memset((void*)_header, 0, header_size);
179 _header->populate(this,
180 core_region_alignment,
181 header_size,
182 base_archive_name_size,
183 base_archive_name_offset,
184 longest_common_prefix_size);
185 }
186
187 void FileMapHeader::populate(FileMapInfo *info, size_t core_region_alignment,
188 size_t header_size, size_t base_archive_name_size,
189 size_t base_archive_name_offset, size_t common_app_classpath_prefix_size) {
190 // 1. We require _generic_header._magic to be at the beginning of the file
191 // 2. FileMapHeader also assumes that _generic_header is at the beginning of the file
192 assert(offset_of(FileMapHeader, _generic_header) == 0, "must be");
193 set_header_size((unsigned int)header_size);
194 set_base_archive_name_offset((unsigned int)base_archive_name_offset);
195 set_base_archive_name_size((unsigned int)base_archive_name_size);
196 set_common_app_classpath_prefix_size((unsigned int)common_app_classpath_prefix_size);
197 set_magic(CDSConfig::is_dumping_dynamic_archive() ? CDS_DYNAMIC_ARCHIVE_MAGIC : CDS_ARCHIVE_MAGIC);
198 set_version(CURRENT_CDS_ARCHIVE_VERSION);
199
200 if (!info->is_static() && base_archive_name_size != 0) {
201 // copy base archive name
202 copy_base_archive_name(CDSConfig::static_archive_path());
203 }
204 _core_region_alignment = core_region_alignment;
205 _obj_alignment = ObjectAlignmentInBytes;
206 _compact_strings = CompactStrings;
207 if (CDSConfig::is_dumping_heap()) {
208 _narrow_oop_mode = CompressedOops::mode();
209 _narrow_oop_base = CompressedOops::base();
210 _narrow_oop_shift = CompressedOops::shift();
211 }
212 _compressed_oops = UseCompressedOops;
213 _compressed_class_ptrs = UseCompressedClassPointers;
214 _use_secondary_supers_table = UseSecondarySupersTable;
215 _max_heap_size = MaxHeapSize;
216 _use_optimized_module_handling = CDSConfig::is_using_optimized_module_handling();
217 _has_aot_linked_classes = CDSConfig::is_dumping_aot_linked_classes();
218 _has_full_module_graph = CDSConfig::is_dumping_full_module_graph();
219 _has_archived_invokedynamic = CDSConfig::is_dumping_invokedynamic();
220 _has_archived_packages = CDSConfig::is_dumping_packages();
221 _has_archived_protection_domains = CDSConfig::is_dumping_protection_domains();
222 _gc_kind = (int)Universe::heap()->kind();
223 jio_snprintf(_gc_name, sizeof(_gc_name), Universe::heap()->name());
224
225 // The following fields are for sanity checks for whether this archive
226 // will function correctly with this JVM and the bootclasspath it's
227 // invoked with.
228
229 // JVM version string ... changes on each build.
230 get_header_version(_jvm_ident);
231
232 _app_class_paths_start_index = ClassLoaderExt::app_class_paths_start_index();
233 _app_module_paths_start_index = ClassLoaderExt::app_module_paths_start_index();
234 _max_used_path_index = ClassLoaderExt::max_used_path_index();
235 _num_module_paths = ClassLoader::num_module_path_entries();
236
237 _verify_local = BytecodeVerificationLocal;
238 _verify_remote = BytecodeVerificationRemote;
239 _has_platform_or_app_classes = ClassLoaderExt::has_platform_or_app_classes();
240 _has_non_jar_in_classpath = ClassLoaderExt::has_non_jar_in_classpath();
241 _requested_base_address = (char*)SharedBaseAddress;
242 _mapped_base_address = (char*)SharedBaseAddress;
243 _allow_archiving_with_java_agent = AllowArchivingWithJavaAgent;
244
245 if (!CDSConfig::is_dumping_dynamic_archive()) {
246 set_shared_path_table(info->_shared_path_table);
247 }
248 }
249
250 void FileMapHeader::copy_base_archive_name(const char* archive) {
251 assert(base_archive_name_size() != 0, "_base_archive_name_size not set");
252 assert(base_archive_name_offset() != 0, "_base_archive_name_offset not set");
253 assert(header_size() > sizeof(*this), "_base_archive_name_size not included in header size?");
254 memcpy((char*)this + base_archive_name_offset(), archive, base_archive_name_size());
255 }
256
257 void FileMapHeader::print(outputStream* st) {
258 ResourceMark rm;
259
260 st->print_cr("- magic: 0x%08x", magic());
261 st->print_cr("- crc: 0x%08x", crc());
262 st->print_cr("- version: 0x%x", version());
263 st->print_cr("- header_size: " UINT32_FORMAT, header_size());
264 st->print_cr("- common_app_classpath_size: " UINT32_FORMAT, common_app_classpath_prefix_size());
265 st->print_cr("- base_archive_name_offset: " UINT32_FORMAT, base_archive_name_offset());
266 st->print_cr("- base_archive_name_size: " UINT32_FORMAT, base_archive_name_size());
267
268 for (int i = 0; i < NUM_CDS_REGIONS; i++) {
269 FileMapRegion* r = region_at(i);
270 r->print(st, i);
271 }
272 st->print_cr("============ end regions ======== ");
273
274 st->print_cr("- core_region_alignment: " SIZE_FORMAT, _core_region_alignment);
275 st->print_cr("- obj_alignment: %d", _obj_alignment);
276 st->print_cr("- narrow_oop_base: " INTPTR_FORMAT, p2i(_narrow_oop_base));
277 st->print_cr("- narrow_oop_shift %d", _narrow_oop_shift);
278 st->print_cr("- compact_strings: %d", _compact_strings);
279 st->print_cr("- max_heap_size: " UINTX_FORMAT, _max_heap_size);
280 st->print_cr("- narrow_oop_mode: %d", _narrow_oop_mode);
281 st->print_cr("- compressed_oops: %d", _compressed_oops);
282 st->print_cr("- compressed_class_ptrs: %d", _compressed_class_ptrs);
283 st->print_cr("- use_secondary_supers_table: %d", _use_secondary_supers_table);
284 st->print_cr("- cloned_vtables_offset: " SIZE_FORMAT_X, _cloned_vtables_offset);
285 st->print_cr("- serialized_data_offset: " SIZE_FORMAT_X, _serialized_data_offset);
286 st->print_cr("- jvm_ident: %s", _jvm_ident);
287 st->print_cr("- shared_path_table_offset: " SIZE_FORMAT_X, _shared_path_table_offset);
288 st->print_cr("- app_class_paths_start_index: %d", _app_class_paths_start_index);
289 st->print_cr("- app_module_paths_start_index: %d", _app_module_paths_start_index);
290 st->print_cr("- num_module_paths: %d", _num_module_paths);
291 st->print_cr("- max_used_path_index: %d", _max_used_path_index);
292 st->print_cr("- verify_local: %d", _verify_local);
293 st->print_cr("- verify_remote: %d", _verify_remote);
294 st->print_cr("- has_platform_or_app_classes: %d", _has_platform_or_app_classes);
295 st->print_cr("- has_non_jar_in_classpath: %d", _has_non_jar_in_classpath);
296 st->print_cr("- requested_base_address: " INTPTR_FORMAT, p2i(_requested_base_address));
297 st->print_cr("- mapped_base_address: " INTPTR_FORMAT, p2i(_mapped_base_address));
298 st->print_cr("- heap_root_segments.roots_count: %d" , _heap_root_segments.roots_count());
299 st->print_cr("- heap_root_segments.base_offset: " SIZE_FORMAT_X, _heap_root_segments.base_offset());
300 st->print_cr("- heap_root_segments.count: " SIZE_FORMAT, _heap_root_segments.count());
301 st->print_cr("- heap_root_segments.max_size_elems: %d", _heap_root_segments.max_size_in_elems());
302 st->print_cr("- heap_root_segments.max_size_bytes: %d", _heap_root_segments.max_size_in_bytes());
303 st->print_cr("- _heap_oopmap_start_pos: " SIZE_FORMAT, _heap_oopmap_start_pos);
304 st->print_cr("- _heap_ptrmap_start_pos: " SIZE_FORMAT, _heap_ptrmap_start_pos);
305 st->print_cr("- _rw_ptrmap_start_pos: " SIZE_FORMAT, _rw_ptrmap_start_pos);
306 st->print_cr("- _ro_ptrmap_start_pos: " SIZE_FORMAT, _ro_ptrmap_start_pos);
307 st->print_cr("- allow_archiving_with_java_agent:%d", _allow_archiving_with_java_agent);
308 st->print_cr("- use_optimized_module_handling: %d", _use_optimized_module_handling);
309 st->print_cr("- has_full_module_graph %d", _has_full_module_graph);
310 st->print_cr("- has_aot_linked_classes %d", _has_aot_linked_classes);
311 st->print_cr("- has_archived_invokedynamic %d", _has_archived_invokedynamic);
312 st->print_cr("- has_archived_packages %d", _has_archived_packages);
313 st->print_cr("- has_archived_protection_domains %d", _has_archived_protection_domains);
314 st->print_cr("- ptrmap_size_in_bits: " SIZE_FORMAT, _ptrmap_size_in_bits);
315 }
316
317 void SharedClassPathEntry::init_as_non_existent(const char* path, TRAPS) {
318 _type = non_existent_entry;
319 set_name(path, CHECK);
320 }
321
322 void SharedClassPathEntry::init(bool is_modules_image,
323 bool is_module_path,
324 ClassPathEntry* cpe, TRAPS) {
325 assert(CDSConfig::is_dumping_archive(), "sanity");
326 _timestamp = 0;
327 _filesize = 0;
328 _from_class_path_attr = false;
329
330 struct stat st;
331 if (os::stat(cpe->name(), &st) == 0) {
332 if ((st.st_mode & S_IFMT) == S_IFDIR) {
333 _type = dir_entry;
334 } else {
335 // The timestamp of the modules_image is not checked at runtime.
336 if (is_modules_image) {
337 _type = modules_image_entry;
338 } else {
339 _type = jar_entry;
340 _timestamp = st.st_mtime;
341 _from_class_path_attr = cpe->from_class_path_attr();
342 }
343 _filesize = st.st_size;
344 _is_module_path = is_module_path;
345 }
346 } else {
347 // The file/dir must exist, or it would not have been added
348 // into ClassLoader::classpath_entry().
349 //
350 // If we can't access a jar file in the boot path, then we can't
351 // make assumptions about where classes get loaded from.
352 log_error(cds)("Unable to open file %s.", cpe->name());
353 MetaspaceShared::unrecoverable_loading_error();
354 }
355
356 // No need to save the name of the module file, as it will be computed at run time
357 // to allow relocation of the JDK directory.
358 const char* name = is_modules_image ? "" : cpe->name();
359 set_name(name, CHECK);
360 }
361
362 void SharedClassPathEntry::set_name(const char* name, TRAPS) {
363 size_t len = strlen(name) + 1;
364 _name = MetadataFactory::new_array<char>(ClassLoaderData::the_null_class_loader_data(), (int)len, CHECK);
365 strcpy(_name->data(), name);
366 }
367
368 void SharedClassPathEntry::copy_from(SharedClassPathEntry* ent, ClassLoaderData* loader_data, TRAPS) {
369 assert(ent != nullptr, "sanity");
370 _type = ent->_type;
371 _is_module_path = ent->_is_module_path;
372 _timestamp = ent->_timestamp;
373 _filesize = ent->_filesize;
374 _from_class_path_attr = ent->_from_class_path_attr;
375 set_name(ent->name(), CHECK);
376
377 if (ent->is_jar() && ent->manifest() != nullptr) {
378 Array<u1>* buf = MetadataFactory::new_array<u1>(loader_data,
379 ent->manifest_size(),
380 CHECK);
381 char* p = (char*)(buf->data());
382 memcpy(p, ent->manifest(), ent->manifest_size());
383 set_manifest(buf);
384 }
385 }
386
387 const char* SharedClassPathEntry::name() const {
388 if (CDSConfig::is_using_archive() && is_modules_image()) {
389 // In order to validate the runtime modules image file size against the archived
390 // size information, we need to obtain the runtime modules image path. The recorded
391 // dump time modules image path in the archive may be different from the runtime path
392 // if the JDK image has beed moved after generating the archive.
393 return ClassLoader::get_jrt_entry()->name();
394 } else {
395 return _name->data();
396 }
397 }
398
399 bool SharedClassPathEntry::validate(bool is_class_path) const {
400 assert(CDSConfig::is_using_archive(), "runtime only");
401
402 struct stat st;
403 const char* name = this->name();
404
405 bool ok = true;
406 log_info(class, path)("checking shared classpath entry: %s", name);
407 if (os::stat(name, &st) != 0 && is_class_path) {
408 // If the archived module path entry does not exist at runtime, it is not fatal
409 // (no need to invalid the shared archive) because the shared runtime visibility check
410 // filters out any archived module classes that do not have a matching runtime
411 // module path location.
412 log_warning(cds)("Required classpath entry does not exist: %s", name);
413 ok = false;
414 } else if (is_dir()) {
415 if (!os::dir_is_empty(name)) {
416 log_warning(cds)("directory is not empty: %s", name);
417 ok = false;
418 }
419 } else {
420 bool size_differs = _filesize != st.st_size;
421 bool time_differs = has_timestamp() && _timestamp != st.st_mtime;
422 if (time_differs || size_differs) {
423 ok = false;
424 if (PrintSharedArchiveAndExit) {
425 log_warning(cds)(time_differs ? "Timestamp mismatch" : "File size mismatch");
426 } else {
427 const char* bad_file_msg = "This file is not the one used while building the shared archive file:";
428 log_warning(cds)("%s %s", bad_file_msg, name);
429 if (!log_is_enabled(Info, cds)) {
430 log_warning(cds)("%s %s", bad_file_msg, name);
431 }
432 if (time_differs) {
433 log_warning(cds)("%s timestamp has changed.", name);
434 }
435 if (size_differs) {
436 log_warning(cds)("%s size has changed.", name);
437 }
438 }
439 }
440 }
441
442 if (PrintSharedArchiveAndExit && !ok) {
443 // If PrintSharedArchiveAndExit is enabled, don't report failure to the
444 // caller. Please see above comments for more details.
445 ok = true;
446 MetaspaceShared::set_archive_loading_failed();
447 }
448 return ok;
449 }
450
451 bool SharedClassPathEntry::check_non_existent() const {
452 assert(_type == non_existent_entry, "must be");
453 log_info(class, path)("should be non-existent: %s", name());
454 struct stat st;
455 if (os::stat(name(), &st) != 0) {
456 log_info(class, path)("ok");
457 return true; // file doesn't exist
458 } else {
459 return false;
460 }
461 }
462
463 void SharedClassPathEntry::metaspace_pointers_do(MetaspaceClosure* it) {
464 it->push(&_name);
465 it->push(&_manifest);
466 }
467
468 void SharedPathTable::metaspace_pointers_do(MetaspaceClosure* it) {
469 it->push(&_entries);
470 }
471
472 void SharedPathTable::dumptime_init(ClassLoaderData* loader_data, TRAPS) {
473 const int num_entries =
474 ClassLoader::num_boot_classpath_entries() +
475 ClassLoader::num_app_classpath_entries() +
476 ClassLoader::num_module_path_entries() +
477 FileMapInfo::num_non_existent_class_paths();
478 _entries = MetadataFactory::new_array<SharedClassPathEntry*>(loader_data, num_entries, CHECK);
479 for (int i = 0; i < num_entries; i++) {
480 SharedClassPathEntry* ent =
481 new (loader_data, SharedClassPathEntry::size(), MetaspaceObj::SharedClassPathEntryType, THREAD) SharedClassPathEntry;
482 _entries->at_put(i, ent);
483 }
484 }
485
486 void FileMapInfo::allocate_shared_path_table(TRAPS) {
487 assert(CDSConfig::is_dumping_archive(), "sanity");
488
489 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
490 ClassPathEntry* jrt = ClassLoader::get_jrt_entry();
491
492 assert(jrt != nullptr,
493 "No modular java runtime image present when allocating the CDS classpath entry table");
494
495 _shared_path_table.dumptime_init(loader_data, CHECK);
496
497 // 1. boot class path
498 int i = 0;
499 i = add_shared_classpaths(i, "boot", jrt, CHECK);
500 i = add_shared_classpaths(i, "app", ClassLoader::app_classpath_entries(), CHECK);
501 i = add_shared_classpaths(i, "module", ClassLoader::module_path_entries(), CHECK);
502
503 for (int x = 0; x < num_non_existent_class_paths(); x++, i++) {
504 const char* path = _non_existent_class_paths->at(x);
505 shared_path(i)->init_as_non_existent(path, CHECK);
506 }
507
508 assert(i == _shared_path_table.size(), "number of shared path entry mismatch");
509 }
510
511 int FileMapInfo::add_shared_classpaths(int i, const char* which, ClassPathEntry *cpe, TRAPS) {
512 while (cpe != nullptr) {
513 bool is_jrt = (cpe == ClassLoader::get_jrt_entry());
514 bool is_module_path = i >= ClassLoaderExt::app_module_paths_start_index();
515 const char* type = (is_jrt ? "jrt" : (cpe->is_jar_file() ? "jar" : "dir"));
516 log_info(class, path)("add %s shared path (%s) %s", which, type, cpe->name());
517 SharedClassPathEntry* ent = shared_path(i);
518 ent->init(is_jrt, is_module_path, cpe, CHECK_0);
519 if (cpe->is_jar_file()) {
520 update_jar_manifest(cpe, ent, CHECK_0);
521 }
522 if (is_jrt) {
523 cpe = ClassLoader::get_next_boot_classpath_entry(cpe);
524 } else {
525 cpe = cpe->next();
526 }
527 i++;
528 }
529
530 return i;
531 }
532
533 void FileMapInfo::check_nonempty_dir_in_shared_path_table() {
534 assert(CDSConfig::is_dumping_archive(), "sanity");
535
536 bool has_nonempty_dir = false;
537
538 int last = _shared_path_table.size() - 1;
539 if (last > ClassLoaderExt::max_used_path_index()) {
540 // no need to check any path beyond max_used_path_index
541 last = ClassLoaderExt::max_used_path_index();
542 }
543
544 for (int i = 0; i <= last; i++) {
545 SharedClassPathEntry *e = shared_path(i);
546 if (e->is_dir()) {
547 const char* path = e->name();
548 if (!os::dir_is_empty(path)) {
549 log_error(cds)("Error: non-empty directory '%s'", path);
550 has_nonempty_dir = true;
551 }
552 }
553 }
554
555 if (has_nonempty_dir) {
556 ClassLoader::exit_with_path_failure("Cannot have non-empty directory in paths", nullptr);
557 }
558 }
559
560 void FileMapInfo::record_non_existent_class_path_entry(const char* path) {
561 assert(CDSConfig::is_dumping_archive(), "sanity");
562 log_info(class, path)("non-existent Class-Path entry %s", path);
563 if (_non_existent_class_paths == nullptr) {
564 _non_existent_class_paths = new (mtClass) GrowableArray<const char*>(10, mtClass);
565 }
566 _non_existent_class_paths->append(os::strdup(path));
567 }
568
569 int FileMapInfo::num_non_existent_class_paths() {
570 assert(CDSConfig::is_dumping_archive(), "sanity");
571 if (_non_existent_class_paths != nullptr) {
572 return _non_existent_class_paths->length();
573 } else {
574 return 0;
575 }
576 }
577
578 int FileMapInfo::get_module_shared_path_index(Symbol* location) {
579 if (location == nullptr) {
580 return 0; // Used by java/lang/reflect/Proxy$ProxyBuilder
581 }
582 if (location->starts_with("jrt:", 4) && get_number_of_shared_paths() > 0) {
583 assert(shared_path(0)->is_modules_image(), "first shared_path must be the modules image");
584 return 0;
585 }
586
587 if (ClassLoaderExt::app_module_paths_start_index() >= get_number_of_shared_paths()) {
588 // The archive(s) were created without --module-path option
589 return -1;
590 }
591
592 if (!location->starts_with("file:", 5)) {
593 return -1;
594 }
595
596 // skip_uri_protocol was also called during dump time -- see ClassLoaderExt::process_module_table()
597 ResourceMark rm;
598 const char* file = ClassLoader::uri_to_path(location->as_C_string());
599 for (int i = ClassLoaderExt::app_module_paths_start_index(); i < get_number_of_shared_paths(); i++) {
600 SharedClassPathEntry* ent = shared_path(i);
601 if (!ent->is_non_existent()) {
602 assert(ent->in_named_module(), "must be");
603 bool cond = strcmp(file, ent->name()) == 0;
604 log_debug(class, path)("get_module_shared_path_index (%d) %s : %s = %s", i,
605 location->as_C_string(), ent->name(), cond ? "same" : "different");
606 if (cond) {
607 return i;
608 }
609 }
610 }
611
612 return -1;
613 }
614
615 class ManifestStream: public ResourceObj {
616 private:
617 u1* _buffer_start; // Buffer bottom
618 u1* _buffer_end; // Buffer top (one past last element)
619 u1* _current; // Current buffer position
620
621 public:
622 // Constructor
623 ManifestStream(u1* buffer, int length) : _buffer_start(buffer),
624 _current(buffer) {
625 _buffer_end = buffer + length;
626 }
627
628 static bool is_attr(u1* attr, const char* name) {
629 return strncmp((const char*)attr, name, strlen(name)) == 0;
630 }
631
632 static char* copy_attr(u1* value, size_t len) {
633 char* buf = NEW_RESOURCE_ARRAY(char, len + 1);
634 strncpy(buf, (char*)value, len);
635 buf[len] = 0;
636 return buf;
637 }
638 };
639
640 void FileMapInfo::update_jar_manifest(ClassPathEntry *cpe, SharedClassPathEntry* ent, TRAPS) {
641 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
642 ResourceMark rm(THREAD);
643 jint manifest_size;
644
645 assert(cpe->is_jar_file() && ent->is_jar(), "the shared class path entry is not a JAR file");
646 char* manifest = ClassLoaderExt::read_manifest(THREAD, cpe, &manifest_size);
647 if (manifest != nullptr) {
648 ManifestStream* stream = new ManifestStream((u1*)manifest,
649 manifest_size);
650 // Copy the manifest into the shared archive
651 manifest = ClassLoaderExt::read_raw_manifest(THREAD, cpe, &manifest_size);
652 Array<u1>* buf = MetadataFactory::new_array<u1>(loader_data,
653 manifest_size,
654 CHECK);
655 char* p = (char*)(buf->data());
656 memcpy(p, manifest, manifest_size);
657 ent->set_manifest(buf);
658 }
659 }
660
661 char* FileMapInfo::skip_first_path_entry(const char* path) {
662 size_t path_sep_len = strlen(os::path_separator());
663 char* p = strstr((char*)path, os::path_separator());
664 if (p != nullptr) {
665 debug_only( {
666 size_t image_name_len = strlen(MODULES_IMAGE_NAME);
667 assert(strncmp(p - image_name_len, MODULES_IMAGE_NAME, image_name_len) == 0,
668 "first entry must be the modules image");
669 } );
670 p += path_sep_len;
671 } else {
672 debug_only( {
673 assert(ClassLoader::string_ends_with(path, MODULES_IMAGE_NAME),
674 "first entry must be the modules image");
675 } );
676 }
677 return p;
678 }
679
680 int FileMapInfo::num_paths(const char* path) {
681 if (path == nullptr) {
682 return 0;
683 }
684 int npaths = 1;
685 char* p = (char*)path;
686 while (p != nullptr) {
687 char* prev = p;
688 p = strstr((char*)p, os::path_separator());
689 if (p != nullptr) {
690 p++;
691 // don't count empty path
692 if ((p - prev) > 1) {
693 npaths++;
694 }
695 }
696 }
697 return npaths;
698 }
699
700 // Returns true if a path within the paths exists and has non-zero size.
701 bool FileMapInfo::check_paths_existence(const char* paths) {
702 ClasspathStream cp_stream(paths);
703 bool exist = false;
704 struct stat st;
705 while (cp_stream.has_next()) {
706 const char* path = cp_stream.get_next();
707 if (os::stat(path, &st) == 0 && st.st_size > 0) {
708 exist = true;
709 break;
710 }
711 }
712 return exist;
713 }
714
715 GrowableArray<const char*>* FileMapInfo::create_dumptime_app_classpath_array() {
716 assert(CDSConfig::is_dumping_archive(), "sanity");
717 GrowableArray<const char*>* path_array = new GrowableArray<const char*>(10);
718 ClassPathEntry* cpe = ClassLoader::app_classpath_entries();
719 while (cpe != nullptr) {
720 path_array->append(cpe->name());
721 cpe = cpe->next();
722 }
723 return path_array;
724 }
725
726 GrowableArray<const char*>* FileMapInfo::create_path_array(const char* paths) {
727 GrowableArray<const char*>* path_array = new GrowableArray<const char*>(10);
728 JavaThread* current = JavaThread::current();
729 ClasspathStream cp_stream(paths);
730 bool non_jar_in_cp = header()->has_non_jar_in_classpath();
731 while (cp_stream.has_next()) {
732 const char* path = cp_stream.get_next();
733 if (!non_jar_in_cp) {
734 struct stat st;
735 if (os::stat(path, &st) == 0) {
736 path_array->append(path);
737 }
738 } else {
739 const char* canonical_path = ClassLoader::get_canonical_path(path, current);
740 if (canonical_path != nullptr) {
741 char* error_msg = nullptr;
742 jzfile* zip = ClassLoader::open_zip_file(canonical_path, &error_msg, current);
743 if (zip != nullptr && error_msg == nullptr) {
744 path_array->append(path);
745 }
746 }
747 }
748 }
749 return path_array;
750 }
751
752 bool FileMapInfo::classpath_failure(const char* msg, const char* name) {
753 ClassLoader::trace_class_path(msg, name);
754 if (PrintSharedArchiveAndExit) {
755 MetaspaceShared::set_archive_loading_failed();
756 }
757 return false;
758 }
759
760 unsigned int FileMapInfo::longest_common_app_classpath_prefix_len(int num_paths,
761 GrowableArray<const char*>* rp_array) {
762 if (num_paths == 0) {
763 return 0;
764 }
765 unsigned int pos;
766 for (pos = 0; ; pos++) {
767 for (int i = 0; i < num_paths; i++) {
768 if (rp_array->at(i)[pos] != '\0' && rp_array->at(i)[pos] == rp_array->at(0)[pos]) {
769 continue;
770 }
771 // search backward for the pos before the file separator char
772 while (pos > 0) {
773 if (rp_array->at(0)[--pos] == *os::file_separator()) {
774 return pos + 1;
775 }
776 }
777 return 0;
778 }
779 }
780 return 0;
781 }
782
783 bool FileMapInfo::check_paths(int shared_path_start_idx, int num_paths, GrowableArray<const char*>* rp_array,
784 unsigned int dumptime_prefix_len, unsigned int runtime_prefix_len) {
785 int i = 0;
786 int j = shared_path_start_idx;
787 while (i < num_paths) {
788 while (shared_path(j)->from_class_path_attr()) {
789 // shared_path(j) was expanded from the JAR file attribute "Class-Path:"
790 // during dump time. It's not included in the -classpath VM argument.
791 j++;
792 }
793 assert(strlen(shared_path(j)->name()) > (size_t)dumptime_prefix_len, "sanity");
794 const char* dumptime_path = shared_path(j)->name() + dumptime_prefix_len;
795 assert(strlen(rp_array->at(i)) > (size_t)runtime_prefix_len, "sanity");
796 const char* runtime_path = rp_array->at(i) + runtime_prefix_len;
797 if (!os::same_files(dumptime_path, runtime_path)) {
798 return false;
799 }
800 i++;
801 j++;
802 }
803 return true;
804 }
805
806 bool FileMapInfo::validate_boot_class_paths() {
807 //
808 // - Archive contains boot classes only - relaxed boot path check:
809 // Extra path elements appended to the boot path at runtime are allowed.
810 //
811 // - Archive contains application or platform classes - strict boot path check:
812 // Validate the entire runtime boot path, which must be compatible
813 // with the dump time boot path. Appending boot path at runtime is not
814 // allowed.
815 //
816
817 // The first entry in boot path is the modules_image (guaranteed by
818 // ClassLoader::setup_boot_search_path()). Skip the first entry. The
819 // path of the runtime modules_image may be different from the dump
820 // time path (e.g. the JDK image is copied to a different location
821 // after generating the shared archive), which is acceptable. For most
822 // common cases, the dump time boot path might contain modules_image only.
823 char* runtime_boot_path = Arguments::get_boot_class_path();
824 char* rp = skip_first_path_entry(runtime_boot_path);
825 assert(shared_path(0)->is_modules_image(), "first shared_path must be the modules image");
826 int dp_len = header()->app_class_paths_start_index() - 1; // ignore the first path to the module image
827 bool match = true;
828
829 bool relaxed_check = !header()->has_platform_or_app_classes();
830 if (dp_len == 0 && rp == nullptr) {
831 return true; // ok, both runtime and dump time boot paths have modules_images only
832 } else if (dp_len == 0 && rp != nullptr) {
833 if (relaxed_check) {
834 return true; // ok, relaxed check, runtime has extra boot append path entries
835 } else {
836 ResourceMark rm;
837 if (check_paths_existence(rp)) {
838 // If a path exists in the runtime boot paths, it is considered a mismatch
839 // since there's no boot path specified during dump time.
840 match = false;
841 }
842 }
843 } else if (dp_len > 0 && rp != nullptr) {
844 int num;
845 ResourceMark rm;
846 GrowableArray<const char*>* rp_array = create_path_array(rp);
847 int rp_len = rp_array->length();
848 if (rp_len >= dp_len) {
849 if (relaxed_check) {
850 // only check the leading entries in the runtime boot path, up to
851 // the length of the dump time boot path
852 num = dp_len;
853 } else {
854 // check the full runtime boot path, must match with dump time
855 num = rp_len;
856 }
857 match = check_paths(1, num, rp_array, 0, 0);
858 } else {
859 // create_path_array() ignores non-existing paths. Although the dump time and runtime boot classpath lengths
860 // are the same initially, after the call to create_path_array(), the runtime boot classpath length could become
861 // shorter. We consider boot classpath mismatch in this case.
862 match = false;
863 }
864 }
865
866 if (!match) {
867 // The paths are different
868 return classpath_failure("[BOOT classpath mismatch, actual =", runtime_boot_path);
869 }
870 return true;
871 }
872
873 bool FileMapInfo::validate_app_class_paths(int shared_app_paths_len) {
874 const char *appcp = Arguments::get_appclasspath();
875 assert(appcp != nullptr, "null app classpath");
876 int rp_len = num_paths(appcp);
877 bool match = false;
878 if (rp_len < shared_app_paths_len) {
879 return classpath_failure("Run time APP classpath is shorter than the one at dump time: ", appcp);
880 }
881 if (shared_app_paths_len != 0 && rp_len != 0) {
882 // Prefix is OK: E.g., dump with -cp foo.jar, but run with -cp foo.jar:bar.jar.
883 ResourceMark rm;
884 GrowableArray<const char*>* rp_array = create_path_array(appcp);
885 if (rp_array->length() == 0) {
886 // None of the jar file specified in the runtime -cp exists.
887 return classpath_failure("None of the jar file specified in the runtime -cp exists: -Djava.class.path=", appcp);
888 }
889 if (rp_array->length() < shared_app_paths_len) {
890 // create_path_array() ignores non-existing paths. Although the dump time and runtime app classpath lengths
891 // are the same initially, after the call to create_path_array(), the runtime app classpath length could become
892 // shorter. We consider app classpath mismatch in this case.
893 return classpath_failure("[APP classpath mismatch, actual: -Djava.class.path=", appcp);
894 }
895
896 // Handling of non-existent entries in the classpath: we eliminate all the non-existent
897 // entries from both the dump time classpath (ClassLoader::update_class_path_entry_list)
898 // and the runtime classpath (FileMapInfo::create_path_array), and check the remaining
899 // entries. E.g.:
900 //
901 // dump : -cp a.jar:NE1:NE2:b.jar -> a.jar:b.jar -> recorded in archive.
902 // run 1: -cp NE3:a.jar:NE4:b.jar -> a.jar:b.jar -> matched
903 // run 2: -cp x.jar:NE4:b.jar -> x.jar:b.jar -> mismatched
904
905 int j = header()->app_class_paths_start_index();
906 match = check_paths(j, shared_app_paths_len, rp_array, 0, 0);
907 if (!match) {
908 // To facilitate app deployment, we allow the JAR files to be moved *together* to
909 // a different location, as long as they are still stored under the same directory
910 // structure. E.g., the following is OK.
911 // java -Xshare:dump -cp /a/Foo.jar:/a/b/Bar.jar ...
912 // java -Xshare:auto -cp /x/y/Foo.jar:/x/y/b/Bar.jar ...
913 unsigned int dumptime_prefix_len = header()->common_app_classpath_prefix_size();
914 unsigned int runtime_prefix_len = longest_common_app_classpath_prefix_len(shared_app_paths_len, rp_array);
915 if (dumptime_prefix_len != 0 || runtime_prefix_len != 0) {
916 log_info(class, path)("LCP length for app classpath (dumptime: %u, runtime: %u)",
917 dumptime_prefix_len, runtime_prefix_len);
918 match = check_paths(j, shared_app_paths_len, rp_array,
919 dumptime_prefix_len, runtime_prefix_len);
920 }
921 if (!match) {
922 return classpath_failure("[APP classpath mismatch, actual: -Djava.class.path=", appcp);
923 }
924 }
925 }
926 return true;
927 }
928
929 void FileMapInfo::log_paths(const char* msg, int start_idx, int end_idx) {
930 LogTarget(Info, class, path) lt;
931 if (lt.is_enabled()) {
932 LogStream ls(lt);
933 ls.print("%s", msg);
934 const char* prefix = "";
935 for (int i = start_idx; i < end_idx; i++) {
936 ls.print("%s%s", prefix, shared_path(i)->name());
937 prefix = os::path_separator();
938 }
939 ls.cr();
940 }
941 }
942
943 void FileMapInfo::extract_module_paths(const char* runtime_path, GrowableArray<const char*>* module_paths) {
944 GrowableArray<const char*>* path_array = create_path_array(runtime_path);
945 int num_paths = path_array->length();
946 for (int i = 0; i < num_paths; i++) {
947 const char* name = path_array->at(i);
948 ClassLoaderExt::extract_jar_files_from_path(name, module_paths);
949 }
950 // module paths are stored in sorted order in the CDS archive.
951 module_paths->sort(ClassLoaderExt::compare_module_path_by_name);
952 }
953
954 bool FileMapInfo::check_module_paths() {
955 const char* runtime_path = Arguments::get_property("jdk.module.path");
956 int archived_num_module_paths = header()->num_module_paths();
957 if (runtime_path == nullptr && archived_num_module_paths == 0) {
958 return true;
959 }
960 if ((runtime_path == nullptr && archived_num_module_paths > 0) ||
961 (runtime_path != nullptr && archived_num_module_paths == 0)) {
962 return false;
963 }
964 ResourceMark rm;
965 GrowableArray<const char*>* module_paths = new GrowableArray<const char*>(3);
966 extract_module_paths(runtime_path, module_paths);
967 int num_paths = module_paths->length();
968 if (num_paths != archived_num_module_paths) {
969 return false;
970 }
971 return check_paths(header()->app_module_paths_start_index(), num_paths, module_paths, 0, 0);
972 }
973
974 bool FileMapInfo::validate_shared_path_table() {
975 assert(CDSConfig::is_using_archive(), "runtime only");
976
977 _validating_shared_path_table = true;
978
979 // Load the shared path table info from the archive header
980 _shared_path_table = header()->shared_path_table();
981
982 bool matched_module_paths = true;
983 if (CDSConfig::is_dumping_dynamic_archive() || header()->has_full_module_graph()) {
984 matched_module_paths = check_module_paths();
985 }
986 if (header()->has_full_module_graph() && !matched_module_paths) {
987 CDSConfig::stop_using_optimized_module_handling();
988 log_info(cds)("optimized module handling: disabled because of mismatched module paths");
989 }
990
991 if (CDSConfig::is_dumping_dynamic_archive()) {
992 // Only support dynamic dumping with the usage of the default CDS archive
993 // or a simple base archive.
994 // If the base layer archive contains additional path component besides
995 // the runtime image and the -cp, dynamic dumping is disabled.
996 //
997 // When dynamic archiving is enabled, the _shared_path_table is overwritten
998 // to include the application path and stored in the top layer archive.
999 assert(shared_path(0)->is_modules_image(), "first shared_path must be the modules image");
1000 if (header()->app_class_paths_start_index() > 1) {
1001 CDSConfig::disable_dumping_dynamic_archive();
1002 log_warning(cds)(
1003 "Dynamic archiving is disabled because base layer archive has appended boot classpath");
1004 }
1005 if (header()->num_module_paths() > 0) {
1006 if (!matched_module_paths) {
1007 CDSConfig::disable_dumping_dynamic_archive();
1008 log_warning(cds)(
1009 "Dynamic archiving is disabled because base layer archive has a different module path");
1010 }
1011 }
1012 }
1013
1014 log_paths("Expecting BOOT path=", 0, header()->app_class_paths_start_index());
1015 log_paths("Expecting -Djava.class.path=", header()->app_class_paths_start_index(), header()->app_module_paths_start_index());
1016
1017 int module_paths_start_index = header()->app_module_paths_start_index();
1018 int shared_app_paths_len = 0;
1019
1020 // validate the path entries up to the _max_used_path_index
1021 for (int i=0; i < header()->max_used_path_index() + 1; i++) {
1022 if (i < module_paths_start_index) {
1023 if (shared_path(i)->validate()) {
1024 // Only count the app class paths not from the "Class-path" attribute of a jar manifest.
1025 if (!shared_path(i)->from_class_path_attr() && i >= header()->app_class_paths_start_index()) {
1026 shared_app_paths_len++;
1027 }
1028 log_info(class, path)("ok");
1029 } else {
1030 if (_dynamic_archive_info != nullptr && _dynamic_archive_info->_is_static) {
1031 assert(!CDSConfig::is_using_archive(), "UseSharedSpaces should be disabled");
1032 }
1033 return false;
1034 }
1035 } else if (i >= module_paths_start_index) {
1036 if (shared_path(i)->validate(false /* not a class path entry */)) {
1037 log_info(class, path)("ok");
1038 } else {
1039 if (_dynamic_archive_info != nullptr && _dynamic_archive_info->_is_static) {
1040 assert(!CDSConfig::is_using_archive(), "UseSharedSpaces should be disabled");
1041 }
1042 return false;
1043 }
1044 }
1045 }
1046
1047 if (header()->max_used_path_index() == 0) {
1048 // default archive only contains the module image in the bootclasspath
1049 assert(shared_path(0)->is_modules_image(), "first shared_path must be the modules image");
1050 } else {
1051 if (!validate_boot_class_paths() || !validate_app_class_paths(shared_app_paths_len)) {
1052 const char* mismatch_msg = "shared class paths mismatch";
1053 const char* hint_msg = log_is_enabled(Info, class, path) ?
1054 "" : " (hint: enable -Xlog:class+path=info to diagnose the failure)";
1055 if (RequireSharedSpaces) {
1056 log_error(cds)("%s%s", mismatch_msg, hint_msg);
1057 MetaspaceShared::unrecoverable_loading_error();
1058 } else {
1059 log_warning(cds)("%s%s", mismatch_msg, hint_msg);
1060 }
1061 return false;
1062 }
1063 }
1064
1065 if (!validate_non_existent_class_paths()) {
1066 return false;
1067 }
1068
1069 _validating_shared_path_table = false;
1070
1071 #if INCLUDE_JVMTI
1072 if (_classpath_entries_for_jvmti != nullptr) {
1073 os::free(_classpath_entries_for_jvmti);
1074 }
1075 size_t sz = sizeof(ClassPathEntry*) * get_number_of_shared_paths();
1076 _classpath_entries_for_jvmti = (ClassPathEntry**)os::malloc(sz, mtClass);
1077 memset((void*)_classpath_entries_for_jvmti, 0, sz);
1078 #endif
1079
1080 return true;
1081 }
1082
1083 bool FileMapInfo::validate_non_existent_class_paths() {
1084 // All of the recorded non-existent paths came from the Class-Path: attribute from the JAR
1085 // files on the app classpath. If any of these are found to exist during runtime,
1086 // it will change how classes are loading for the app loader. For safety, disable
1087 // loading of archived platform/app classes (currently there's no way to disable just the
1088 // app classes).
1089
1090 assert(CDSConfig::is_using_archive(), "runtime only");
1091 for (int i = header()->app_module_paths_start_index() + header()->num_module_paths();
1092 i < get_number_of_shared_paths();
1093 i++) {
1094 SharedClassPathEntry* ent = shared_path(i);
1095 if (!ent->check_non_existent()) {
1096 if (header()->has_aot_linked_classes()) {
1097 log_error(cds)("CDS archive has aot-linked classes. It cannot be used because the "
1098 "file %s exists", ent->name());
1099 return false;
1100 } else {
1101 log_warning(cds)("Archived non-system classes are disabled because the "
1102 "file %s exists", ent->name());
1103 header()->set_has_platform_or_app_classes(false);
1104 }
1105 }
1106 }
1107
1108 return true;
1109 }
1110
1111 // A utility class for reading/validating the GenericCDSFileMapHeader portion of
1112 // a CDS archive's header. The file header of all CDS archives with versions from
1113 // CDS_GENERIC_HEADER_SUPPORTED_MIN_VERSION (12) are guaranteed to always start
1114 // with GenericCDSFileMapHeader. This makes it possible to read important information
1115 // from a CDS archive created by a different version of HotSpot, so that we can
1116 // automatically regenerate the archive as necessary (JDK-8261455).
1117 class FileHeaderHelper {
1118 int _fd;
1119 bool _is_valid;
1120 bool _is_static;
1121 GenericCDSFileMapHeader* _header;
1122 const char* _archive_name;
1123 const char* _base_archive_name;
1124
1125 public:
1126 FileHeaderHelper(const char* archive_name, bool is_static) {
1127 _fd = -1;
1128 _is_valid = false;
1129 _header = nullptr;
1130 _base_archive_name = nullptr;
1131 _archive_name = archive_name;
1132 _is_static = is_static;
1133 }
1134
1135 ~FileHeaderHelper() {
1136 if (_header != nullptr) {
1137 FREE_C_HEAP_ARRAY(char, _header);
1138 }
1139 if (_fd != -1) {
1140 ::close(_fd);
1141 }
1142 }
1143
1144 bool initialize() {
1145 assert(_archive_name != nullptr, "Archive name is null");
1146 _fd = os::open(_archive_name, O_RDONLY | O_BINARY, 0);
1147 if (_fd < 0) {
1148 log_info(cds)("Specified shared archive not found (%s)", _archive_name);
1149 return false;
1150 }
1151 return initialize(_fd);
1152 }
1153
1154 // for an already opened file, do not set _fd
1155 bool initialize(int fd) {
1156 assert(_archive_name != nullptr, "Archive name is null");
1157 assert(fd != -1, "Archive must be opened already");
1158 // First read the generic header so we know the exact size of the actual header.
1159 GenericCDSFileMapHeader gen_header;
1160 size_t size = sizeof(GenericCDSFileMapHeader);
1161 os::lseek(fd, 0, SEEK_SET);
1162 size_t n = ::read(fd, (void*)&gen_header, (unsigned int)size);
1163 if (n != size) {
1164 log_warning(cds)("Unable to read generic CDS file map header from shared archive");
1165 return false;
1166 }
1167
1168 if (gen_header._magic != CDS_ARCHIVE_MAGIC &&
1169 gen_header._magic != CDS_DYNAMIC_ARCHIVE_MAGIC) {
1170 log_warning(cds)("The shared archive file has a bad magic number: %#x", gen_header._magic);
1171 return false;
1172 }
1173
1174 if (gen_header._version < CDS_GENERIC_HEADER_SUPPORTED_MIN_VERSION) {
1175 log_warning(cds)("Cannot handle shared archive file version 0x%x. Must be at least 0x%x.",
1176 gen_header._version, CDS_GENERIC_HEADER_SUPPORTED_MIN_VERSION);
1177 return false;
1178 }
1179
1180 if (gen_header._version != CURRENT_CDS_ARCHIVE_VERSION) {
1181 log_warning(cds)("The shared archive file version 0x%x does not match the required version 0x%x.",
1182 gen_header._version, CURRENT_CDS_ARCHIVE_VERSION);
1183 }
1184
1185 size_t filelen = os::lseek(fd, 0, SEEK_END);
1186 if (gen_header._header_size >= filelen) {
1187 log_warning(cds)("Archive file header larger than archive file");
1188 return false;
1189 }
1190
1191 // Read the actual header and perform more checks
1192 size = gen_header._header_size;
1193 _header = (GenericCDSFileMapHeader*)NEW_C_HEAP_ARRAY(char, size, mtInternal);
1194 os::lseek(fd, 0, SEEK_SET);
1195 n = ::read(fd, (void*)_header, (unsigned int)size);
1196 if (n != size) {
1197 log_warning(cds)("Unable to read actual CDS file map header from shared archive");
1198 return false;
1199 }
1200
1201 if (!check_header_crc()) {
1202 return false;
1203 }
1204
1205 if (!check_and_init_base_archive_name()) {
1206 return false;
1207 }
1208
1209 // All fields in the GenericCDSFileMapHeader has been validated.
1210 _is_valid = true;
1211 return true;
1212 }
1213
1214 GenericCDSFileMapHeader* get_generic_file_header() {
1215 assert(_header != nullptr && _is_valid, "must be a valid archive file");
1216 return _header;
1217 }
1218
1219 const char* base_archive_name() {
1220 assert(_header != nullptr && _is_valid, "must be a valid archive file");
1221 return _base_archive_name;
1222 }
1223
1224 private:
1225 bool check_header_crc() const {
1226 if (VerifySharedSpaces) {
1227 FileMapHeader* header = (FileMapHeader*)_header;
1228 int actual_crc = header->compute_crc();
1229 if (actual_crc != header->crc()) {
1230 log_info(cds)("_crc expected: %d", header->crc());
1231 log_info(cds)(" actual: %d", actual_crc);
1232 log_warning(cds)("Header checksum verification failed.");
1233 return false;
1234 }
1235 }
1236 return true;
1237 }
1238
1239 bool check_and_init_base_archive_name() {
1240 unsigned int name_offset = _header->_base_archive_name_offset;
1241 unsigned int name_size = _header->_base_archive_name_size;
1242 unsigned int header_size = _header->_header_size;
1243
1244 if (name_offset + name_size < name_offset) {
1245 log_warning(cds)("base_archive_name offset/size overflow: " UINT32_FORMAT "/" UINT32_FORMAT,
1246 name_offset, name_size);
1247 return false;
1248 }
1249 if (_header->_magic == CDS_ARCHIVE_MAGIC) {
1250 if (name_offset != 0) {
1251 log_warning(cds)("static shared archive must have zero _base_archive_name_offset");
1252 return false;
1253 }
1254 if (name_size != 0) {
1255 log_warning(cds)("static shared archive must have zero _base_archive_name_size");
1256 return false;
1257 }
1258 } else {
1259 assert(_header->_magic == CDS_DYNAMIC_ARCHIVE_MAGIC, "must be");
1260 if ((name_size == 0 && name_offset != 0) ||
1261 (name_size != 0 && name_offset == 0)) {
1262 // If either is zero, both must be zero. This indicates that we are using the default base archive.
1263 log_warning(cds)("Invalid base_archive_name offset/size: " UINT32_FORMAT "/" UINT32_FORMAT,
1264 name_offset, name_size);
1265 return false;
1266 }
1267 if (name_size > 0) {
1268 if (name_offset + name_size > header_size) {
1269 log_warning(cds)("Invalid base_archive_name offset/size (out of range): "
1270 UINT32_FORMAT " + " UINT32_FORMAT " > " UINT32_FORMAT ,
1271 name_offset, name_size, header_size);
1272 return false;
1273 }
1274 const char* name = ((const char*)_header) + _header->_base_archive_name_offset;
1275 if (name[name_size - 1] != '\0' || strlen(name) != name_size - 1) {
1276 log_warning(cds)("Base archive name is damaged");
1277 return false;
1278 }
1279 if (!os::file_exists(name)) {
1280 log_warning(cds)("Base archive %s does not exist", name);
1281 return false;
1282 }
1283 _base_archive_name = name;
1284 }
1285 }
1286
1287 return true;
1288 }
1289 };
1290
1291 // Return value:
1292 // false:
1293 // <archive_name> is not a valid archive. *base_archive_name is set to null.
1294 // true && (*base_archive_name) == nullptr:
1295 // <archive_name> is a valid static archive.
1296 // true && (*base_archive_name) != nullptr:
1297 // <archive_name> is a valid dynamic archive.
1298 bool FileMapInfo::get_base_archive_name_from_header(const char* archive_name,
1299 char** base_archive_name) {
1300 FileHeaderHelper file_helper(archive_name, false);
1301 *base_archive_name = nullptr;
1302
1303 if (!file_helper.initialize()) {
1304 return false;
1305 }
1306 GenericCDSFileMapHeader* header = file_helper.get_generic_file_header();
1307 if (header->_magic != CDS_DYNAMIC_ARCHIVE_MAGIC) {
1308 assert(header->_magic == CDS_ARCHIVE_MAGIC, "must be");
1309 if (AutoCreateSharedArchive) {
1310 log_warning(cds)("AutoCreateSharedArchive is ignored because %s is a static archive", archive_name);
1311 }
1312 return true;
1313 }
1314
1315 const char* base = file_helper.base_archive_name();
1316 if (base == nullptr) {
1317 *base_archive_name = CDSConfig::default_archive_path();
1318 } else {
1319 *base_archive_name = os::strdup_check_oom(base);
1320 }
1321
1322 return true;
1323 }
1324
1325 // Read the FileMapInfo information from the file.
1326
1327 bool FileMapInfo::init_from_file(int fd) {
1328 FileHeaderHelper file_helper(_full_path, _is_static);
1329 if (!file_helper.initialize(fd)) {
1330 log_warning(cds)("Unable to read the file header.");
1331 return false;
1332 }
1333 GenericCDSFileMapHeader* gen_header = file_helper.get_generic_file_header();
1334
1335 if (_is_static) {
1336 if (gen_header->_magic != CDS_ARCHIVE_MAGIC) {
1337 log_warning(cds)("Not a base shared archive: %s", _full_path);
1338 return false;
1339 }
1340 } else {
1341 if (gen_header->_magic != CDS_DYNAMIC_ARCHIVE_MAGIC) {
1342 log_warning(cds)("Not a top shared archive: %s", _full_path);
1343 return false;
1344 }
1345 }
1346
1347 _header = (FileMapHeader*)os::malloc(gen_header->_header_size, mtInternal);
1348 os::lseek(fd, 0, SEEK_SET); // reset to begin of the archive
1349 size_t size = gen_header->_header_size;
1350 size_t n = ::read(fd, (void*)_header, (unsigned int)size);
1351 if (n != size) {
1352 log_warning(cds)("Failed to read file header from the top archive file\n");
1353 return false;
1354 }
1355
1356 if (header()->version() != CURRENT_CDS_ARCHIVE_VERSION) {
1357 log_info(cds)("_version expected: 0x%x", CURRENT_CDS_ARCHIVE_VERSION);
1358 log_info(cds)(" actual: 0x%x", header()->version());
1359 log_warning(cds)("The shared archive file has the wrong version.");
1360 return false;
1361 }
1362
1363 int common_path_size = header()->common_app_classpath_prefix_size();
1364 if (common_path_size < 0) {
1365 log_warning(cds)("common app classpath prefix len < 0");
1366 return false;
1367 }
1368
1369 unsigned int base_offset = header()->base_archive_name_offset();
1370 unsigned int name_size = header()->base_archive_name_size();
1371 unsigned int header_size = header()->header_size();
1372 if (base_offset != 0 && name_size != 0) {
1373 if (header_size != base_offset + name_size) {
1374 log_info(cds)("_header_size: " UINT32_FORMAT, header_size);
1375 log_info(cds)("common_app_classpath_size: " UINT32_FORMAT, header()->common_app_classpath_prefix_size());
1376 log_info(cds)("base_archive_name_size: " UINT32_FORMAT, header()->base_archive_name_size());
1377 log_info(cds)("base_archive_name_offset: " UINT32_FORMAT, header()->base_archive_name_offset());
1378 log_warning(cds)("The shared archive file has an incorrect header size.");
1379 return false;
1380 }
1381 }
1382
1383 const char* actual_ident = header()->jvm_ident();
1384
1385 if (actual_ident[JVM_IDENT_MAX-1] != 0) {
1386 log_warning(cds)("JVM version identifier is corrupted.");
1387 return false;
1388 }
1389
1390 char expected_ident[JVM_IDENT_MAX];
1391 get_header_version(expected_ident);
1392 if (strncmp(actual_ident, expected_ident, JVM_IDENT_MAX-1) != 0) {
1393 log_info(cds)("_jvm_ident expected: %s", expected_ident);
1394 log_info(cds)(" actual: %s", actual_ident);
1395 log_warning(cds)("The shared archive file was created by a different"
1396 " version or build of HotSpot");
1397 return false;
1398 }
1399
1400 _file_offset = header()->header_size(); // accounts for the size of _base_archive_name
1401
1402 size_t len = os::lseek(fd, 0, SEEK_END);
1403
1404 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
1405 FileMapRegion* r = region_at(i);
1406 if (r->file_offset() > len || len - r->file_offset() < r->used()) {
1407 log_warning(cds)("The shared archive file has been truncated.");
1408 return false;
1409 }
1410 }
1411
1412 return true;
1413 }
1414
1415 void FileMapInfo::seek_to_position(size_t pos) {
1416 if (os::lseek(_fd, (long)pos, SEEK_SET) < 0) {
1417 log_error(cds)("Unable to seek to position " SIZE_FORMAT, pos);
1418 MetaspaceShared::unrecoverable_loading_error();
1419 }
1420 }
1421
1422 // Read the FileMapInfo information from the file.
1423 bool FileMapInfo::open_for_read() {
1424 if (_file_open) {
1425 return true;
1426 }
1427 log_info(cds)("trying to map %s", _full_path);
1428 int fd = os::open(_full_path, O_RDONLY | O_BINARY, 0);
1429 if (fd < 0) {
1430 if (errno == ENOENT) {
1431 log_info(cds)("Specified shared archive not found (%s)", _full_path);
1432 } else {
1433 log_warning(cds)("Failed to open shared archive file (%s)",
1434 os::strerror(errno));
1435 }
1436 return false;
1437 } else {
1438 log_info(cds)("Opened archive %s.", _full_path);
1439 }
1440
1441 _fd = fd;
1442 _file_open = true;
1443 return true;
1444 }
1445
1446 // Write the FileMapInfo information to the file.
1447
1448 void FileMapInfo::open_for_write() {
1449 LogMessage(cds) msg;
1450 if (msg.is_info()) {
1451 msg.info("Dumping shared data to file: ");
1452 msg.info(" %s", _full_path);
1453 }
1454
1455 #ifdef _WINDOWS // On Windows, need WRITE permission to remove the file.
1456 chmod(_full_path, _S_IREAD | _S_IWRITE);
1457 #endif
1458
1459 // Use remove() to delete the existing file because, on Unix, this will
1460 // allow processes that have it open continued access to the file.
1461 remove(_full_path);
1462 int fd = os::open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444);
1463 if (fd < 0) {
1464 log_error(cds)("Unable to create shared archive file %s: (%s).", _full_path,
1465 os::strerror(errno));
1466 MetaspaceShared::writing_error();
1467 return;
1468 }
1469 _fd = fd;
1470 _file_open = true;
1471
1472 // Seek past the header. We will write the header after all regions are written
1473 // and their CRCs computed.
1474 size_t header_bytes = header()->header_size();
1475
1476 header_bytes = align_up(header_bytes, MetaspaceShared::core_region_alignment());
1477 _file_offset = header_bytes;
1478 seek_to_position(_file_offset);
1479 }
1480
1481 // Write the header to the file, seek to the next allocation boundary.
1482
1483 void FileMapInfo::write_header() {
1484 _file_offset = 0;
1485 seek_to_position(_file_offset);
1486 assert(is_file_position_aligned(), "must be");
1487 write_bytes(header(), header()->header_size());
1488 }
1489
1490 size_t FileMapRegion::used_aligned() const {
1491 return align_up(used(), MetaspaceShared::core_region_alignment());
1492 }
1493
1494 void FileMapRegion::init(int region_index, size_t mapping_offset, size_t size, bool read_only,
1495 bool allow_exec, int crc) {
1496 _is_heap_region = HeapShared::is_heap_region(region_index);
1497 _is_bitmap_region = (region_index == MetaspaceShared::bm);
1498 _mapping_offset = mapping_offset;
1499 _used = size;
1500 _read_only = read_only;
1501 _allow_exec = allow_exec;
1502 _crc = crc;
1503 _mapped_from_file = false;
1504 _mapped_base = nullptr;
1505 }
1506
1507 void FileMapRegion::init_oopmap(size_t offset, size_t size_in_bits) {
1508 _oopmap_offset = offset;
1509 _oopmap_size_in_bits = size_in_bits;
1510 }
1511
1512 void FileMapRegion::init_ptrmap(size_t offset, size_t size_in_bits) {
1513 _ptrmap_offset = offset;
1514 _ptrmap_size_in_bits = size_in_bits;
1515 }
1516
1517 bool FileMapRegion::check_region_crc(char* base) const {
1518 // This function should be called after the region has been properly
1519 // loaded into memory via FileMapInfo::map_region() or FileMapInfo::read_region().
1520 // I.e., this->mapped_base() must be valid.
1521 size_t sz = used();
1522 if (sz == 0) {
1523 return true;
1524 }
1525
1526 assert(base != nullptr, "must be initialized");
1527 int crc = ClassLoader::crc32(0, base, (jint)sz);
1528 if (crc != this->crc()) {
1529 log_warning(cds)("Checksum verification failed.");
1530 return false;
1531 }
1532 return true;
1533 }
1534
1535 static const char* region_name(int region_index) {
1536 static const char* names[] = {
1537 "rw", "ro", "bm", "hp", "cc",
1538 };
1539 const int num_regions = sizeof(names)/sizeof(names[0]);
1540 assert(0 <= region_index && region_index < num_regions, "sanity");
1541
1542 return names[region_index];
1543 }
1544
1545 BitMapView FileMapInfo::bitmap_view(int region_index, bool is_oopmap) {
1546 FileMapRegion* r = region_at(region_index);
1547 char* bitmap_base = is_static() ? FileMapInfo::current_info()->map_bitmap_region() : FileMapInfo::dynamic_info()->map_bitmap_region();
1548 bitmap_base += is_oopmap ? r->oopmap_offset() : r->ptrmap_offset();
1549 size_t size_in_bits = is_oopmap ? r->oopmap_size_in_bits() : r->ptrmap_size_in_bits();
1550
1551 log_debug(cds, reloc)("mapped %s relocation %smap @ " INTPTR_FORMAT " (" SIZE_FORMAT " bits)",
1552 region_name(region_index), is_oopmap ? "oop" : "ptr",
1553 p2i(bitmap_base), size_in_bits);
1554
1555 return BitMapView((BitMap::bm_word_t*)(bitmap_base), size_in_bits);
1556 }
1557
1558 BitMapView FileMapInfo::oopmap_view(int region_index) {
1559 return bitmap_view(region_index, /*is_oopmap*/true);
1560 }
1561
1562 BitMapView FileMapInfo::ptrmap_view(int region_index) {
1563 return bitmap_view(region_index, /*is_oopmap*/false);
1564 }
1565
1566 void FileMapRegion::print(outputStream* st, int region_index) {
1567 st->print_cr("============ region ============= %d \"%s\"", region_index, region_name(region_index));
1568 st->print_cr("- crc: 0x%08x", _crc);
1569 st->print_cr("- read_only: %d", _read_only);
1570 st->print_cr("- allow_exec: %d", _allow_exec);
1571 st->print_cr("- is_heap_region: %d", _is_heap_region);
1572 st->print_cr("- is_bitmap_region: %d", _is_bitmap_region);
1573 st->print_cr("- mapped_from_file: %d", _mapped_from_file);
1574 st->print_cr("- file_offset: " SIZE_FORMAT_X, _file_offset);
1575 st->print_cr("- mapping_offset: " SIZE_FORMAT_X, _mapping_offset);
1576 st->print_cr("- used: " SIZE_FORMAT, _used);
1577 st->print_cr("- oopmap_offset: " SIZE_FORMAT_X, _oopmap_offset);
1578 st->print_cr("- oopmap_size_in_bits: " SIZE_FORMAT, _oopmap_size_in_bits);
1579 st->print_cr("- ptrmap_offset: " SIZE_FORMAT_X, _ptrmap_offset);
1580 st->print_cr("- ptrmap_size_in_bits: " SIZE_FORMAT, _ptrmap_size_in_bits);
1581 st->print_cr("- mapped_base: " INTPTR_FORMAT, p2i(_mapped_base));
1582 }
1583
1584 void FileMapInfo::write_region(int region, char* base, size_t size,
1585 bool read_only, bool allow_exec) {
1586 assert(CDSConfig::is_dumping_archive(), "sanity");
1587
1588 FileMapRegion* r = region_at(region);
1589 char* requested_base;
1590 size_t mapping_offset = 0;
1591
1592 if (region == MetaspaceShared::bm) {
1593 requested_base = nullptr; // always null for bm region
1594 } else if (size == 0) {
1595 // This is an unused region (e.g., a heap region when !INCLUDE_CDS_JAVA_HEAP)
1596 requested_base = nullptr;
1597 } else if (HeapShared::is_heap_region(region)) {
1598 assert(HeapShared::can_write(), "sanity");
1599 #if INCLUDE_CDS_JAVA_HEAP
1600 assert(!CDSConfig::is_dumping_dynamic_archive(), "must be");
1601 requested_base = (char*)ArchiveHeapWriter::requested_address();
1602 if (UseCompressedOops) {
1603 mapping_offset = (size_t)((address)requested_base - CompressedOops::base());
1604 assert((mapping_offset >> CompressedOops::shift()) << CompressedOops::shift() == mapping_offset, "must be");
1605 } else {
1606 mapping_offset = 0; // not used with !UseCompressedOops
1607 }
1608 #endif // INCLUDE_CDS_JAVA_HEAP
1609 } else {
1610 char* requested_SharedBaseAddress = (char*)MetaspaceShared::requested_base_address();
1611 requested_base = ArchiveBuilder::current()->to_requested(base);
1612 assert(requested_base >= requested_SharedBaseAddress, "must be");
1613 mapping_offset = requested_base - requested_SharedBaseAddress;
1614 }
1615
1616 r->set_file_offset(_file_offset);
1617 int crc = ClassLoader::crc32(0, base, (jint)size);
1618 if (size > 0) {
1619 log_info(cds)("Shared file region (%s) %d: " SIZE_FORMAT_W(8)
1620 " bytes, addr " INTPTR_FORMAT " file offset 0x%08" PRIxPTR
1621 " crc 0x%08x",
1622 region_name(region), region, size, p2i(requested_base), _file_offset, crc);
1623 } else {
1624 log_info(cds)("Shared file region (%s) %d: " SIZE_FORMAT_W(8)
1625 " bytes", region_name(region), region, size);
1626 }
1627
1628 r->init(region, mapping_offset, size, read_only, allow_exec, crc);
1629
1630 if (base != nullptr) {
1631 write_bytes_aligned(base, size);
1632 }
1633 }
1634
1635 static size_t write_bitmap(const CHeapBitMap* map, char* output, size_t offset) {
1636 size_t size_in_bytes = map->size_in_bytes();
1637 map->write_to((BitMap::bm_word_t*)(output + offset), size_in_bytes);
1638 return offset + size_in_bytes;
1639 }
1640
1641 // The sorting code groups the objects with non-null oop/ptrs together.
1642 // Relevant bitmaps then have lots of leading and trailing zeros, which
1643 // we do not have to store.
1644 size_t FileMapInfo::remove_bitmap_zeros(CHeapBitMap* map) {
1645 BitMap::idx_t first_set = map->find_first_set_bit(0);
1646 BitMap::idx_t last_set = map->find_last_set_bit(0);
1647 size_t old_size = map->size();
1648
1649 // Slice and resize bitmap
1650 map->truncate(first_set, last_set + 1);
1651
1652 assert(map->at(0), "First bit should be set");
1653 assert(map->at(map->size() - 1), "Last bit should be set");
1654 assert(map->size() <= old_size, "sanity");
1655
1656 return first_set;
1657 }
1658
1659 char* FileMapInfo::write_bitmap_region(CHeapBitMap* rw_ptrmap, CHeapBitMap* ro_ptrmap,
1660 CHeapBitMap* cc_ptrmap,
1661 ArchiveHeapInfo* heap_info,
1662 size_t &size_in_bytes) {
1663 size_t removed_rw_leading_zeros = remove_bitmap_zeros(rw_ptrmap);
1664 size_t removed_ro_leading_zeros = remove_bitmap_zeros(ro_ptrmap);
1665 header()->set_rw_ptrmap_start_pos(removed_rw_leading_zeros);
1666 header()->set_ro_ptrmap_start_pos(removed_ro_leading_zeros);
1667 size_in_bytes = rw_ptrmap->size_in_bytes() + ro_ptrmap->size_in_bytes() + cc_ptrmap->size_in_bytes();
1668
1669 if (heap_info->is_used()) {
1670 // Remove leading and trailing zeros
1671 size_t removed_oop_leading_zeros = remove_bitmap_zeros(heap_info->oopmap());
1672 size_t removed_ptr_leading_zeros = remove_bitmap_zeros(heap_info->ptrmap());
1673 header()->set_heap_oopmap_start_pos(removed_oop_leading_zeros);
1674 header()->set_heap_ptrmap_start_pos(removed_ptr_leading_zeros);
1675
1676 size_in_bytes += heap_info->oopmap()->size_in_bytes();
1677 size_in_bytes += heap_info->ptrmap()->size_in_bytes();
1678 }
1679
1680 // The bitmap region contains up to 4 parts:
1681 // rw_ptrmap: metaspace pointers inside the read-write region
1682 // ro_ptrmap: metaspace pointers inside the read-only region
1683 // heap_info->oopmap(): Java oop pointers in the heap region
1684 // heap_info->ptrmap(): metaspace pointers in the heap region
1685 char* buffer = NEW_C_HEAP_ARRAY(char, size_in_bytes, mtClassShared);
1686 size_t written = 0;
1687
1688 region_at(MetaspaceShared::rw)->init_ptrmap(0, rw_ptrmap->size());
1689 written = write_bitmap(rw_ptrmap, buffer, written);
1690
1691 region_at(MetaspaceShared::ro)->init_ptrmap(written, ro_ptrmap->size());
1692 written = write_bitmap(ro_ptrmap, buffer, written);
1693
1694 region_at(MetaspaceShared::cc)->init_ptrmap(written, cc_ptrmap->size());
1695 written = write_bitmap(cc_ptrmap, buffer, written);
1696
1697 if (heap_info->is_used()) {
1698 FileMapRegion* r = region_at(MetaspaceShared::hp);
1699
1700 r->init_oopmap(written, heap_info->oopmap()->size());
1701 written = write_bitmap(heap_info->oopmap(), buffer, written);
1702
1703 r->init_ptrmap(written, heap_info->ptrmap()->size());
1704 written = write_bitmap(heap_info->ptrmap(), buffer, written);
1705 }
1706
1707 write_region(MetaspaceShared::bm, (char*)buffer, size_in_bytes, /*read_only=*/true, /*allow_exec=*/false);
1708 return buffer;
1709 }
1710
1711 size_t FileMapInfo::write_heap_region(ArchiveHeapInfo* heap_info) {
1712 char* buffer_start = heap_info->buffer_start();
1713 size_t buffer_size = heap_info->buffer_byte_size();
1714 write_region(MetaspaceShared::hp, buffer_start, buffer_size, false, false);
1715 header()->set_heap_root_segments(heap_info->heap_root_segments());
1716 return buffer_size;
1717 }
1718
1719 // Dump bytes to file -- at the current file position.
1720
1721 void FileMapInfo::write_bytes(const void* buffer, size_t nbytes) {
1722 assert(_file_open, "must be");
1723 if (!os::write(_fd, buffer, nbytes)) {
1724 // If the shared archive is corrupted, close it and remove it.
1725 close();
1726 remove(_full_path);
1727 MetaspaceShared::writing_error("Unable to write to shared archive file.");
1728 }
1729 _file_offset += nbytes;
1730 }
1731
1732 bool FileMapInfo::is_file_position_aligned() const {
1733 return _file_offset == align_up(_file_offset,
1734 MetaspaceShared::core_region_alignment());
1735 }
1736
1737 // Align file position to an allocation unit boundary.
1738
1739 void FileMapInfo::align_file_position() {
1740 assert(_file_open, "must be");
1741 size_t new_file_offset = align_up(_file_offset,
1742 MetaspaceShared::core_region_alignment());
1743 if (new_file_offset != _file_offset) {
1744 _file_offset = new_file_offset;
1745 // Seek one byte back from the target and write a byte to insure
1746 // that the written file is the correct length.
1747 _file_offset -= 1;
1748 seek_to_position(_file_offset);
1749 char zero = 0;
1750 write_bytes(&zero, 1);
1751 }
1752 }
1753
1754
1755 // Dump bytes to file -- at the current file position.
1756
1757 void FileMapInfo::write_bytes_aligned(const void* buffer, size_t nbytes) {
1758 align_file_position();
1759 write_bytes(buffer, nbytes);
1760 align_file_position();
1761 }
1762
1763 // Close the shared archive file. This does NOT unmap mapped regions.
1764
1765 void FileMapInfo::close() {
1766 if (_file_open) {
1767 if (::close(_fd) < 0) {
1768 MetaspaceShared::unrecoverable_loading_error("Unable to close the shared archive file.");
1769 }
1770 _file_open = false;
1771 _fd = -1;
1772 }
1773 }
1774
1775 /*
1776 * Same as os::map_memory() but also pretouches if AlwaysPreTouch is enabled.
1777 */
1778 static char* map_memory(int fd, const char* file_name, size_t file_offset,
1779 char *addr, size_t bytes, bool read_only,
1780 bool allow_exec, MemTag mem_tag = mtNone) {
1781 char* mem = os::map_memory(fd, file_name, file_offset, addr, bytes,
1782 AlwaysPreTouch ? false : read_only,
1783 allow_exec, mem_tag);
1784 if (mem != nullptr && AlwaysPreTouch) {
1785 os::pretouch_memory(mem, mem + bytes);
1786 }
1787 return mem;
1788 }
1789
1790 // JVM/TI RedefineClasses() support:
1791 // Remap the shared readonly space to shared readwrite, private.
1792 bool FileMapInfo::remap_shared_readonly_as_readwrite() {
1793 int idx = MetaspaceShared::ro;
1794 FileMapRegion* r = region_at(idx);
1795 if (!r->read_only()) {
1796 // the space is already readwrite so we are done
1797 return true;
1798 }
1799 size_t size = r->used_aligned();
1800 if (!open_for_read()) {
1801 return false;
1802 }
1803 char *addr = r->mapped_base();
1804 // This path should not be reached for Windows; see JDK-8222379.
1805 assert(WINDOWS_ONLY(false) NOT_WINDOWS(true), "Don't call on Windows");
1806 // Replace old mapping with new one that is writable.
1807 char *base = os::map_memory(_fd, _full_path, r->file_offset(),
1808 addr, size, false /* !read_only */,
1809 r->allow_exec());
1810 close();
1811 // These have to be errors because the shared region is now unmapped.
1812 if (base == nullptr) {
1813 log_error(cds)("Unable to remap shared readonly space (errno=%d).", errno);
1814 vm_exit(1);
1815 }
1816 if (base != addr) {
1817 log_error(cds)("Unable to remap shared readonly space (errno=%d).", errno);
1818 vm_exit(1);
1819 }
1820 r->set_read_only(false);
1821 return true;
1822 }
1823
1824 // Memory map a region in the address space.
1825 static const char* shared_region_name[] = { "ReadWrite", "ReadOnly", "Bitmap", "Heap", "Code" };
1826
1827 MapArchiveResult FileMapInfo::map_regions(int regions[], int num_regions, char* mapped_base_address, ReservedSpace rs) {
1828 DEBUG_ONLY(FileMapRegion* last_region = nullptr);
1829 intx addr_delta = mapped_base_address - header()->requested_base_address();
1830
1831 // Make sure we don't attempt to use header()->mapped_base_address() unless
1832 // it's been successfully mapped.
1833 DEBUG_ONLY(header()->set_mapped_base_address((char*)(uintptr_t)0xdeadbeef);)
1834
1835 for (int i = 0; i < num_regions; i++) {
1836 int idx = regions[i];
1837 MapArchiveResult result = map_region(idx, addr_delta, mapped_base_address, rs);
1838 if (result != MAP_ARCHIVE_SUCCESS) {
1839 return result;
1840 }
1841 FileMapRegion* r = region_at(idx);
1842 DEBUG_ONLY(if (last_region != nullptr) {
1843 // Ensure that the OS won't be able to allocate new memory spaces between any mapped
1844 // regions, or else it would mess up the simple comparison in MetaspaceObj::is_shared().
1845 assert(r->mapped_base() == last_region->mapped_end(), "must have no gaps");
1846 }
1847 last_region = r;)
1848 log_info(cds)("Mapped %s region #%d at base " INTPTR_FORMAT " top " INTPTR_FORMAT " (%s)", is_static() ? "static " : "dynamic",
1849 idx, p2i(r->mapped_base()), p2i(r->mapped_end()),
1850 shared_region_name[idx]);
1851
1852 }
1853
1854 header()->set_mapped_base_address(header()->requested_base_address() + addr_delta);
1855 if (addr_delta != 0 && !relocate_pointers_in_core_regions(addr_delta)) {
1856 return MAP_ARCHIVE_OTHER_FAILURE;
1857 }
1858
1859 return MAP_ARCHIVE_SUCCESS;
1860 }
1861
1862 bool FileMapInfo::read_region(int i, char* base, size_t size, bool do_commit) {
1863 FileMapRegion* r = region_at(i);
1864 if (do_commit) {
1865 log_info(cds)("Commit %s region #%d at base " INTPTR_FORMAT " top " INTPTR_FORMAT " (%s)%s",
1866 is_static() ? "static " : "dynamic", i, p2i(base), p2i(base + size),
1867 shared_region_name[i], r->allow_exec() ? " exec" : "");
1868 if (!os::commit_memory(base, size, r->allow_exec())) {
1869 log_error(cds)("Failed to commit %s region #%d (%s)", is_static() ? "static " : "dynamic",
1870 i, shared_region_name[i]);
1871 return false;
1872 }
1873 }
1874 if (os::lseek(_fd, (long)r->file_offset(), SEEK_SET) != (int)r->file_offset() ||
1875 read_bytes(base, size) != size) {
1876 return false;
1877 }
1878
1879 if (VerifySharedSpaces && !r->check_region_crc(base)) {
1880 return false;
1881 }
1882
1883 r->set_mapped_from_file(false);
1884 r->set_mapped_base(base);
1885
1886 return true;
1887 }
1888
1889 MapArchiveResult FileMapInfo::map_region(int i, intx addr_delta, char* mapped_base_address, ReservedSpace rs) {
1890 assert(!HeapShared::is_heap_region(i), "sanity");
1891 FileMapRegion* r = region_at(i);
1892 size_t size = r->used_aligned();
1893 char *requested_addr = mapped_base_address + r->mapping_offset();
1894 assert(r->mapped_base() == nullptr, "must be not mapped yet");
1895 assert(requested_addr != nullptr, "must be specified");
1896
1897 r->set_mapped_from_file(false);
1898
1899 if (MetaspaceShared::use_windows_memory_mapping()) {
1900 // Windows cannot remap read-only shared memory to read-write when required for
1901 // RedefineClasses, which is also used by JFR. Always map windows regions as RW.
1902 r->set_read_only(false);
1903 } else if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space() ||
1904 Arguments::has_jfr_option()) {
1905 // If a tool agent is in use (debugging enabled), or JFR, we must map the address space RW
1906 r->set_read_only(false);
1907 } else if (addr_delta != 0) {
1908 r->set_read_only(false); // Need to patch the pointers
1909 }
1910
1911 if (MetaspaceShared::use_windows_memory_mapping() && rs.is_reserved()) {
1912 // This is the second time we try to map the archive(s). We have already created a ReservedSpace
1913 // that covers all the FileMapRegions to ensure all regions can be mapped. However, Windows
1914 // can't mmap into a ReservedSpace, so we just ::read() the data. We're going to patch all the
1915 // regions anyway, so there's no benefit for mmap anyway.
1916 if (!read_region(i, requested_addr, size, /* do_commit = */ true)) {
1917 log_info(cds)("Failed to read %s shared space into reserved space at " INTPTR_FORMAT,
1918 shared_region_name[i], p2i(requested_addr));
1919 return MAP_ARCHIVE_OTHER_FAILURE; // oom or I/O error.
1920 } else {
1921 assert(r->mapped_base() != nullptr, "must be initialized");
1922 return MAP_ARCHIVE_SUCCESS;
1923 }
1924 } else {
1925 // Note that this may either be a "fresh" mapping into unreserved address
1926 // space (Windows, first mapping attempt), or a mapping into pre-reserved
1927 // space (Posix). See also comment in MetaspaceShared::map_archives().
1928 bool read_only = r->read_only() && !CDSConfig::is_dumping_final_static_archive();
1929 char* base = map_memory(_fd, _full_path, r->file_offset(),
1930 requested_addr, size, read_only,
1931 r->allow_exec(), mtClassShared);
1932 if (base != requested_addr) {
1933 log_info(cds)("Unable to map %s shared space at " INTPTR_FORMAT,
1934 shared_region_name[i], p2i(requested_addr));
1935 _memory_mapping_failed = true;
1936 return MAP_ARCHIVE_MMAP_FAILURE;
1937 }
1938
1939 if (VerifySharedSpaces && !r->check_region_crc(requested_addr)) {
1940 return MAP_ARCHIVE_OTHER_FAILURE;
1941 }
1942
1943 r->set_mapped_from_file(true);
1944 r->set_mapped_base(requested_addr);
1945
1946 return MAP_ARCHIVE_SUCCESS;
1947 }
1948 }
1949
1950 // The return value is the location of the archive relocation bitmap.
1951 char* FileMapInfo::map_bitmap_region() {
1952 FileMapRegion* r = region_at(MetaspaceShared::bm);
1953 if (r->mapped_base() != nullptr) {
1954 return r->mapped_base();
1955 }
1956 bool read_only = true, allow_exec = false;
1957 char* requested_addr = nullptr; // allow OS to pick any location
1958 char* bitmap_base = map_memory(_fd, _full_path, r->file_offset(),
1959 requested_addr, r->used_aligned(), read_only, allow_exec, mtClassShared);
1960 if (bitmap_base == nullptr) {
1961 log_info(cds)("failed to map relocation bitmap");
1962 return nullptr;
1963 }
1964
1965 if (VerifySharedSpaces && !r->check_region_crc(bitmap_base)) {
1966 log_error(cds)("relocation bitmap CRC error");
1967 if (!os::unmap_memory(bitmap_base, r->used_aligned())) {
1968 fatal("os::unmap_memory of relocation bitmap failed");
1969 }
1970 return nullptr;
1971 }
1972
1973 r->set_mapped_from_file(true);
1974 r->set_mapped_base(bitmap_base);
1975 log_info(cds)("Mapped %s region #%d at base " INTPTR_FORMAT " top " INTPTR_FORMAT " (%s)",
1976 is_static() ? "static " : "dynamic",
1977 MetaspaceShared::bm, p2i(r->mapped_base()), p2i(r->mapped_end()),
1978 shared_region_name[MetaspaceShared::bm]);
1979 return bitmap_base;
1980 }
1981
1982 bool FileMapInfo::map_cached_code_region(ReservedSpace rs) {
1983 FileMapRegion* r = region_at(MetaspaceShared::cc);
1984 assert(r->used() > 0 && r->used_aligned() == rs.size(), "must be");
1985
1986 char* requested_base = rs.base();
1987 assert(requested_base != nullptr, "should be inside code cache");
1988
1989 char* mapped_base;
1990 if (MetaspaceShared::use_windows_memory_mapping()) {
1991 if (!read_region(MetaspaceShared::cc, requested_base, r->used_aligned(), /* do_commit = */ true)) {
1992 log_info(cds)("Failed to read cc shared space into reserved space at " INTPTR_FORMAT,
1993 p2i(requested_base));
1994 return false;
1995 }
1996 mapped_base = requested_base;
1997 } else {
1998 bool read_only = false, allow_exec = false;
1999 mapped_base = map_memory(_fd, _full_path, r->file_offset(),
2000 requested_base, r->used_aligned(), read_only, allow_exec, mtClassShared);
2001 }
2002 if (mapped_base == nullptr) {
2003 log_info(cds)("failed to map cached code region");
2004 return false;
2005 } else {
2006 assert(mapped_base == requested_base, "must be");
2007 r->set_mapped_from_file(true);
2008 r->set_mapped_base(mapped_base);
2009 relocate_pointers_in_cached_code_region();
2010 log_info(cds)("Mapped static region #%d at base " INTPTR_FORMAT " top " INTPTR_FORMAT " (%s)",
2011 MetaspaceShared::cc, p2i(r->mapped_base()), p2i(r->mapped_end()),
2012 shared_region_name[MetaspaceShared::cc]);
2013 return true;
2014 }
2015 }
2016
2017 class CachedCodeRelocator: public BitMapClosure {
2018 address _code_requested_base;
2019 address* _patch_base;
2020 intx _code_delta;
2021 intx _metadata_delta;
2022
2023 public:
2024 CachedCodeRelocator(address code_requested_base, address code_mapped_base,
2025 intx metadata_delta) {
2026 _code_requested_base = code_requested_base;
2027 _patch_base = (address*)code_mapped_base;
2028 _code_delta = code_mapped_base - code_requested_base;
2029 _metadata_delta = metadata_delta;
2030 }
2031
2032 bool do_bit(size_t offset) {
2033 address* p = _patch_base + offset;
2034 address requested_ptr = *p;
2035 if (requested_ptr < _code_requested_base) {
2036 *p = requested_ptr + _metadata_delta;
2037 } else {
2038 *p = requested_ptr + _code_delta;
2039 }
2040 return true; // keep iterating
2041 }
2042 };
2043
2044 void FileMapInfo::relocate_pointers_in_cached_code_region() {
2045 FileMapRegion* r = region_at(MetaspaceShared::cc);
2046 char* bitmap_base = map_bitmap_region();
2047
2048 BitMapView cc_ptrmap = ptrmap_view(MetaspaceShared::cc);
2049 if (cc_ptrmap.size() == 0) {
2050 return;
2051 }
2052
2053 address core_regions_requested_base = (address)header()->requested_base_address();
2054 address core_regions_mapped_base = (address)header()->mapped_base_address();
2055 address cc_region_requested_base = core_regions_requested_base + r->mapping_offset();
2056 address cc_region_mapped_base = (address)r->mapped_base();
2057
2058 size_t max_bits_for_core_regions = pointer_delta(mapped_end(), mapped_base(), // FIXME - renamed to core_regions_mapped_base(), etc
2059 sizeof(address));
2060
2061 CachedCodeRelocator patcher(cc_region_requested_base, cc_region_mapped_base,
2062 core_regions_mapped_base - core_regions_requested_base);
2063 cc_ptrmap.iterate(&patcher);
2064 }
2065
2066 // This is called when we cannot map the archive at the requested[ base address (usually 0x800000000).
2067 // We relocate all pointers in the 2 core regions (ro, rw).
2068 bool FileMapInfo::relocate_pointers_in_core_regions(intx addr_delta) {
2069 log_debug(cds, reloc)("runtime archive relocation start");
2070 char* bitmap_base = map_bitmap_region();
2071
2072 if (bitmap_base == nullptr) {
2073 return false; // OOM, or CRC check failure
2074 } else {
2075 BitMapView rw_ptrmap = ptrmap_view(MetaspaceShared::rw);
2076 BitMapView ro_ptrmap = ptrmap_view(MetaspaceShared::ro);
2077
2078 FileMapRegion* rw_region = first_core_region();
2079 FileMapRegion* ro_region = last_core_region();
2080
2081 // Patch all pointers inside the RW region
2082 address rw_patch_base = (address)rw_region->mapped_base();
2083 address rw_patch_end = (address)rw_region->mapped_end();
2084
2085 // Patch all pointers inside the RO region
2086 address ro_patch_base = (address)ro_region->mapped_base();
2087 address ro_patch_end = (address)ro_region->mapped_end();
2088
2089 // the current value of the pointers to be patched must be within this
2090 // range (i.e., must be between the requested base address and the address of the current archive).
2091 // Note: top archive may point to objects in the base archive, but not the other way around.
2092 address valid_old_base = (address)header()->requested_base_address();
2093 address valid_old_end = valid_old_base + mapping_end_offset();
2094
2095 // after patching, the pointers must point inside this range
2096 // (the requested location of the archive, as mapped at runtime).
2097 address valid_new_base = (address)header()->mapped_base_address();
2098 address valid_new_end = (address)mapped_end();
2099
2100 SharedDataRelocator rw_patcher((address*)rw_patch_base + header()->rw_ptrmap_start_pos(), (address*)rw_patch_end, valid_old_base, valid_old_end,
2101 valid_new_base, valid_new_end, addr_delta);
2102 SharedDataRelocator ro_patcher((address*)ro_patch_base + header()->ro_ptrmap_start_pos(), (address*)ro_patch_end, valid_old_base, valid_old_end,
2103 valid_new_base, valid_new_end, addr_delta);
2104 rw_ptrmap.iterate(&rw_patcher);
2105 ro_ptrmap.iterate(&ro_patcher);
2106
2107 // The MetaspaceShared::bm region will be unmapped in MetaspaceShared::initialize_shared_spaces().
2108
2109 log_debug(cds, reloc)("runtime archive relocation done");
2110 return true;
2111 }
2112 }
2113
2114 size_t FileMapInfo::read_bytes(void* buffer, size_t count) {
2115 assert(_file_open, "Archive file is not open");
2116 size_t n = ::read(_fd, buffer, (unsigned int)count);
2117 if (n != count) {
2118 // Close the file if there's a problem reading it.
2119 close();
2120 return 0;
2121 }
2122 _file_offset += count;
2123 return count;
2124 }
2125
2126 // Get the total size in bytes of a read only region
2127 size_t FileMapInfo::readonly_total() {
2128 size_t total = 0;
2129 if (current_info() != nullptr) {
2130 FileMapRegion* r = FileMapInfo::current_info()->region_at(MetaspaceShared::ro);
2131 if (r->read_only()) total += r->used();
2132 }
2133 if (dynamic_info() != nullptr) {
2134 FileMapRegion* r = FileMapInfo::dynamic_info()->region_at(MetaspaceShared::ro);
2135 if (r->read_only()) total += r->used();
2136 }
2137 return total;
2138 }
2139
2140 #if INCLUDE_CDS_JAVA_HEAP
2141 MemRegion FileMapInfo::_mapped_heap_memregion;
2142
2143 bool FileMapInfo::has_heap_region() {
2144 return (region_at(MetaspaceShared::hp)->used() > 0);
2145 }
2146
2147 // Returns the address range of the archived heap region computed using the
2148 // current oop encoding mode. This range may be different than the one seen at
2149 // dump time due to encoding mode differences. The result is used in determining
2150 // if/how these regions should be relocated at run time.
2151 MemRegion FileMapInfo::get_heap_region_requested_range() {
2152 FileMapRegion* r = region_at(MetaspaceShared::hp);
2153 size_t size = r->used();
2154 assert(size > 0, "must have non-empty heap region");
2155
2156 address start = heap_region_requested_address();
2157 address end = start + size;
2158 log_info(cds)("Requested heap region [" INTPTR_FORMAT " - " INTPTR_FORMAT "] = " SIZE_FORMAT_W(8) " bytes",
2159 p2i(start), p2i(end), size);
2160
2161 return MemRegion((HeapWord*)start, (HeapWord*)end);
2162 }
2163
2164 void FileMapInfo::map_or_load_heap_region() {
2165 bool success = false;
2166
2167 if (can_use_heap_region()) {
2168 if (ArchiveHeapLoader::can_map()) {
2169 success = map_heap_region();
2170 } else if (ArchiveHeapLoader::can_load()) {
2171 success = ArchiveHeapLoader::load_heap_region(this);
2172 } else {
2173 if (!UseCompressedOops && !ArchiveHeapLoader::can_map()) {
2174 // TODO - remove implicit knowledge of G1
2175 log_info(cds)("Cannot use CDS heap data. UseG1GC is required for -XX:-UseCompressedOops");
2176 } else {
2177 log_info(cds)("Cannot use CDS heap data. UseEpsilonGC, UseG1GC, UseSerialGC, UseParallelGC, or UseShenandoahGC are required.");
2178 }
2179 }
2180 }
2181
2182 if (!success) {
2183 if (CDSConfig::is_using_aot_linked_classes() && !CDSConfig::is_dumping_final_static_archive()) {
2184 // It's too later to recover -- we have already committed to use the archived metaspace objects, but
2185 // the archived heap objects cannot be loaded, so we don't have the archived FMG to guarantee that
2186 // all AOT-linked classes are visible.
2187 //
2188 // We get here because the heap is too small. The app will fail anyway. So let's quit.
2189 MetaspaceShared::unrecoverable_loading_error("CDS archive has aot-linked classes but the archived "
2190 "heap objects cannot be loaded. Try increasing your heap size.");
2191 }
2192 CDSConfig::stop_using_full_module_graph("archive heap loading failed");
2193 }
2194 }
2195
2196 bool FileMapInfo::can_use_heap_region() {
2197 if (!has_heap_region()) {
2198 return false;
2199 }
2200 if (JvmtiExport::should_post_class_file_load_hook() && JvmtiExport::has_early_class_hook_env()) {
2201 ShouldNotReachHere(); // CDS should have been disabled.
2202 // The archived objects are mapped at JVM start-up, but we don't know if
2203 // j.l.String or j.l.Class might be replaced by the ClassFileLoadHook,
2204 // which would make the archived String or mirror objects invalid. Let's be safe and not
2205 // use the archived objects. These 2 classes are loaded during the JVMTI "early" stage.
2206 //
2207 // If JvmtiExport::has_early_class_hook_env() is false, the classes of some objects
2208 // in the archived subgraphs may be replaced by the ClassFileLoadHook. But that's OK
2209 // because we won't install an archived object subgraph if the klass of any of the
2210 // referenced objects are replaced. See HeapShared::initialize_from_archived_subgraph().
2211 }
2212
2213 // We pre-compute narrow Klass IDs with the runtime mapping start intended to be the base, and a shift of
2214 // ArchiveHeapWriter::precomputed_narrow_klass_shift. We enforce this encoding at runtime (see
2215 // CompressedKlassPointers::initialize_for_given_encoding()). Therefore, the following assertions must
2216 // hold:
2217 address archive_narrow_klass_base = (address)header()->mapped_base_address();
2218 const int archive_narrow_klass_shift = ArchiveHeapWriter::precomputed_narrow_klass_shift;
2219
2220 log_info(cds)("CDS archive was created with max heap size = " SIZE_FORMAT "M, and the following configuration:",
2221 max_heap_size()/M);
2222 log_info(cds)(" narrow_klass_base at mapping start address, narrow_klass_shift = %d",
2223 archive_narrow_klass_shift);
2224 log_info(cds)(" narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d",
2225 narrow_oop_mode(), p2i(narrow_oop_base()), narrow_oop_shift());
2226 log_info(cds)("The current max heap size = " SIZE_FORMAT "M, G1HeapRegion::GrainBytes = " SIZE_FORMAT,
2227 MaxHeapSize/M, G1HeapRegion::GrainBytes);
2228 log_info(cds)(" narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
2229 p2i(CompressedKlassPointers::base()), CompressedKlassPointers::shift());
2230 log_info(cds)(" narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d",
2231 CompressedOops::mode(), p2i(CompressedOops::base()), CompressedOops::shift());
2232 log_info(cds)(" heap range = [" PTR_FORMAT " - " PTR_FORMAT "]",
2233 UseCompressedOops ? p2i(CompressedOops::begin()) :
2234 UseG1GC ? p2i((address)G1CollectedHeap::heap()->reserved().start()) : 0L,
2235 UseCompressedOops ? p2i(CompressedOops::end()) :
2236 UseG1GC ? p2i((address)G1CollectedHeap::heap()->reserved().end()) : 0L);
2237
2238 assert(archive_narrow_klass_base == CompressedKlassPointers::base(), "Unexpected encoding base encountered "
2239 "(" PTR_FORMAT ", expected " PTR_FORMAT ")", p2i(CompressedKlassPointers::base()), p2i(archive_narrow_klass_base));
2240 assert(archive_narrow_klass_shift == CompressedKlassPointers::shift(), "Unexpected encoding shift encountered "
2241 "(%d, expected %d)", CompressedKlassPointers::shift(), archive_narrow_klass_shift);
2242
2243 return true;
2244 }
2245
2246 // The actual address of this region during dump time.
2247 address FileMapInfo::heap_region_dumptime_address() {
2248 FileMapRegion* r = region_at(MetaspaceShared::hp);
2249 assert(CDSConfig::is_using_archive(), "runtime only");
2250 assert(is_aligned(r->mapping_offset(), sizeof(HeapWord)), "must be");
2251 if (UseCompressedOops) {
2252 return /*dumptime*/ narrow_oop_base() + r->mapping_offset();
2253 } else {
2254 return heap_region_requested_address();
2255 }
2256 }
2257
2258 // The address where this region can be mapped into the runtime heap without
2259 // patching any of the pointers that are embedded in this region.
2260 address FileMapInfo::heap_region_requested_address() {
2261 assert(CDSConfig::is_using_archive(), "runtime only");
2262 FileMapRegion* r = region_at(MetaspaceShared::hp);
2263 assert(is_aligned(r->mapping_offset(), sizeof(HeapWord)), "must be");
2264 assert(ArchiveHeapLoader::can_map(), "cannot be used by ArchiveHeapLoader::can_load() mode");
2265 if (UseCompressedOops) {
2266 // We can avoid relocation if each region's offset from the runtime CompressedOops::base()
2267 // is the same as its offset from the CompressedOops::base() during dumptime.
2268 // Note that CompressedOops::base() may be different between dumptime and runtime.
2269 //
2270 // Example:
2271 // Dumptime base = 0x1000 and shift is 0. We have a region at address 0x2000. There's a
2272 // narrowOop P stored in this region that points to an object at address 0x2200.
2273 // P's encoded value is 0x1200.
2274 //
2275 // Runtime base = 0x4000 and shift is also 0. If we map this region at 0x5000, then
2276 // the value P can remain 0x1200. The decoded address = (0x4000 + (0x1200 << 0)) = 0x5200,
2277 // which is the runtime location of the referenced object.
2278 return /*runtime*/ CompressedOops::base() + r->mapping_offset();
2279 } else {
2280 // This was the hard-coded requested base address used at dump time. With uncompressed oops,
2281 // the heap range is assigned by the OS so we will most likely have to relocate anyway, no matter
2282 // what base address was picked at duump time.
2283 return (address)ArchiveHeapWriter::NOCOOPS_REQUESTED_BASE;
2284 }
2285 }
2286
2287 bool FileMapInfo::map_heap_region() {
2288 if (map_heap_region_impl()) {
2289 #ifdef ASSERT
2290 // The "old" regions must be parsable -- we cannot have any unused space
2291 // at the start of the lowest G1 region that contains archived objects.
2292 assert(is_aligned(_mapped_heap_memregion.start(), G1HeapRegion::GrainBytes), "must be");
2293
2294 // Make sure we map at the very top of the heap - see comments in
2295 // init_heap_region_relocation().
2296 MemRegion heap_range = G1CollectedHeap::heap()->reserved();
2297 assert(heap_range.contains(_mapped_heap_memregion), "must be");
2298
2299 address heap_end = (address)heap_range.end();
2300 address mapped_heap_region_end = (address)_mapped_heap_memregion.end();
2301 assert(heap_end >= mapped_heap_region_end, "must be");
2302 assert(heap_end - mapped_heap_region_end < (intx)(G1HeapRegion::GrainBytes),
2303 "must be at the top of the heap to avoid fragmentation");
2304 #endif
2305
2306 ArchiveHeapLoader::set_mapped();
2307 return true;
2308 } else {
2309 return false;
2310 }
2311 }
2312
2313 bool FileMapInfo::map_heap_region_impl() {
2314 assert(UseG1GC, "the following code assumes G1");
2315
2316 FileMapRegion* r = region_at(MetaspaceShared::hp);
2317 size_t size = r->used();
2318 if (size == 0) {
2319 return false; // no archived java heap data
2320 }
2321
2322 size_t word_size = size / HeapWordSize;
2323 address requested_start = heap_region_requested_address();
2324
2325 log_info(cds)("Preferred address to map heap data (to avoid relocation) is " INTPTR_FORMAT, p2i(requested_start));
2326
2327 // allocate from java heap
2328 HeapWord* start = G1CollectedHeap::heap()->alloc_archive_region(word_size, (HeapWord*)requested_start);
2329 if (start == nullptr) {
2330 log_info(cds)("UseSharedSpaces: Unable to allocate java heap region for archive heap.");
2331 return false;
2332 }
2333
2334 _mapped_heap_memregion = MemRegion(start, word_size);
2335
2336 // Map the archived heap data. No need to call MemTracker::record_virtual_memory_tag()
2337 // for mapped region as it is part of the reserved java heap, which is already recorded.
2338 char* addr = (char*)_mapped_heap_memregion.start();
2339 char* base;
2340
2341 if (MetaspaceShared::use_windows_memory_mapping()) {
2342 if (!read_region(MetaspaceShared::hp, addr,
2343 align_up(_mapped_heap_memregion.byte_size(), os::vm_page_size()),
2344 /* do_commit = */ true)) {
2345 dealloc_heap_region();
2346 log_error(cds)("Failed to read archived heap region into " INTPTR_FORMAT, p2i(addr));
2347 return false;
2348 }
2349 // Checks for VerifySharedSpaces is already done inside read_region()
2350 base = addr;
2351 } else {
2352 base = map_memory(_fd, _full_path, r->file_offset(),
2353 addr, _mapped_heap_memregion.byte_size(), r->read_only(),
2354 r->allow_exec());
2355 if (base == nullptr || base != addr) {
2356 dealloc_heap_region();
2357 log_info(cds)("UseSharedSpaces: Unable to map at required address in java heap. "
2358 INTPTR_FORMAT ", size = " SIZE_FORMAT " bytes",
2359 p2i(addr), _mapped_heap_memregion.byte_size());
2360 return false;
2361 }
2362
2363 if (VerifySharedSpaces && !r->check_region_crc(base)) {
2364 dealloc_heap_region();
2365 log_info(cds)("UseSharedSpaces: mapped heap region is corrupt");
2366 return false;
2367 }
2368 }
2369
2370 r->set_mapped_base(base);
2371
2372 // If the requested range is different from the range allocated by GC, then
2373 // the pointers need to be patched.
2374 address mapped_start = (address) _mapped_heap_memregion.start();
2375 ptrdiff_t delta = mapped_start - requested_start;
2376 if (UseCompressedOops &&
2377 (narrow_oop_mode() != CompressedOops::mode() ||
2378 narrow_oop_shift() != CompressedOops::shift())) {
2379 _heap_pointers_need_patching = true;
2380 }
2381 if (delta != 0) {
2382 _heap_pointers_need_patching = true;
2383 }
2384 ArchiveHeapLoader::init_mapped_heap_info(mapped_start, delta, narrow_oop_shift());
2385
2386 if (_heap_pointers_need_patching) {
2387 char* bitmap_base = map_bitmap_region();
2388 if (bitmap_base == nullptr) {
2389 log_info(cds)("CDS heap cannot be used because bitmap region cannot be mapped");
2390 dealloc_heap_region();
2391 unmap_region(MetaspaceShared::hp);
2392 _heap_pointers_need_patching = false;
2393 return false;
2394 }
2395 }
2396 log_info(cds)("Heap data mapped at " INTPTR_FORMAT ", size = " SIZE_FORMAT_W(8) " bytes",
2397 p2i(mapped_start), _mapped_heap_memregion.byte_size());
2398 log_info(cds)("CDS heap data relocation delta = " INTX_FORMAT " bytes", delta);
2399 return true;
2400 }
2401
2402 narrowOop FileMapInfo::encoded_heap_region_dumptime_address() {
2403 assert(CDSConfig::is_using_archive(), "runtime only");
2404 assert(UseCompressedOops, "sanity");
2405 FileMapRegion* r = region_at(MetaspaceShared::hp);
2406 return CompressedOops::narrow_oop_cast(r->mapping_offset() >> narrow_oop_shift());
2407 }
2408
2409 void FileMapInfo::patch_heap_embedded_pointers() {
2410 if (!ArchiveHeapLoader::is_mapped() || !_heap_pointers_need_patching) {
2411 return;
2412 }
2413
2414 char* bitmap_base = map_bitmap_region();
2415 assert(bitmap_base != nullptr, "must have already been mapped");
2416
2417 FileMapRegion* r = region_at(MetaspaceShared::hp);
2418 ArchiveHeapLoader::patch_embedded_pointers(
2419 this, _mapped_heap_memregion,
2420 (address)(region_at(MetaspaceShared::bm)->mapped_base()) + r->oopmap_offset(),
2421 r->oopmap_size_in_bits());
2422 }
2423
2424 void FileMapInfo::fixup_mapped_heap_region() {
2425 if (ArchiveHeapLoader::is_mapped()) {
2426 assert(!_mapped_heap_memregion.is_empty(), "sanity");
2427
2428 // Populate the archive regions' G1BlockOffsetTables. That ensures
2429 // fast G1BlockOffsetTable::block_start operations for any given address
2430 // within the archive regions when trying to find start of an object
2431 // (e.g. during card table scanning).
2432 G1CollectedHeap::heap()->populate_archive_regions_bot(_mapped_heap_memregion);
2433 }
2434 }
2435
2436 // dealloc the archive regions from java heap
2437 void FileMapInfo::dealloc_heap_region() {
2438 G1CollectedHeap::heap()->dealloc_archive_regions(_mapped_heap_memregion);
2439 }
2440 #endif // INCLUDE_CDS_JAVA_HEAP
2441
2442 void FileMapInfo::unmap_regions(int regions[], int num_regions) {
2443 for (int r = 0; r < num_regions; r++) {
2444 int idx = regions[r];
2445 unmap_region(idx);
2446 }
2447 }
2448
2449 // Unmap a memory region in the address space.
2450
2451 void FileMapInfo::unmap_region(int i) {
2452 FileMapRegion* r = region_at(i);
2453 char* mapped_base = r->mapped_base();
2454 size_t size = r->used_aligned();
2455
2456 if (mapped_base != nullptr) {
2457 if (size > 0 && r->mapped_from_file()) {
2458 log_info(cds)("Unmapping region #%d at base " INTPTR_FORMAT " (%s)", i, p2i(mapped_base),
2459 shared_region_name[i]);
2460 if (!os::unmap_memory(mapped_base, size)) {
2461 fatal("os::unmap_memory failed");
2462 }
2463 }
2464 r->set_mapped_base(nullptr);
2465 }
2466 }
2467
2468 void FileMapInfo::assert_mark(bool check) {
2469 if (!check) {
2470 MetaspaceShared::unrecoverable_loading_error("Mark mismatch while restoring from shared file.");
2471 }
2472 }
2473
2474 FileMapInfo* FileMapInfo::_current_info = nullptr;
2475 FileMapInfo* FileMapInfo::_dynamic_archive_info = nullptr;
2476 bool FileMapInfo::_heap_pointers_need_patching = false;
2477 SharedPathTable FileMapInfo::_shared_path_table;
2478 bool FileMapInfo::_validating_shared_path_table = false;
2479 bool FileMapInfo::_memory_mapping_failed = false;
2480 GrowableArray<const char*>* FileMapInfo::_non_existent_class_paths = nullptr;
2481
2482 // Open the shared archive file, read and validate the header
2483 // information (version, boot classpath, etc.). If initialization
2484 // fails, shared spaces are disabled and the file is closed.
2485 //
2486 // Validation of the archive is done in two steps:
2487 //
2488 // [1] validate_header() - done here.
2489 // [2] validate_shared_path_table - this is done later, because the table is in the RW
2490 // region of the archive, which is not mapped yet.
2491 bool FileMapInfo::initialize() {
2492 assert(CDSConfig::is_using_archive(), "UseSharedSpaces expected.");
2493 assert(Arguments::has_jimage(), "The shared archive file cannot be used with an exploded module build.");
2494
2495 if (JvmtiExport::should_post_class_file_load_hook() && JvmtiExport::has_early_class_hook_env()) {
2496 // CDS assumes that no classes resolved in vmClasses::resolve_all()
2497 // are replaced at runtime by JVMTI ClassFileLoadHook. All of those classes are resolved
2498 // during the JVMTI "early" stage, so we can still use CDS if
2499 // JvmtiExport::has_early_class_hook_env() is false.
2500 log_info(cds)("CDS is disabled because early JVMTI ClassFileLoadHook is in use.");
2501 return false;
2502 }
2503
2504 if (!open_for_read() || !init_from_file(_fd) || !validate_header()) {
2505 if (_is_static) {
2506 log_info(cds)("Initialize static archive failed.");
2507 return false;
2508 } else {
2509 log_info(cds)("Initialize dynamic archive failed.");
2510 if (AutoCreateSharedArchive) {
2511 CDSConfig::enable_dumping_dynamic_archive();
2512 ArchiveClassesAtExit = CDSConfig::dynamic_archive_path();
2513 }
2514 return false;
2515 }
2516 }
2517
2518 return true;
2519 }
2520
2521 bool FileMapInfo::validate_aot_class_linking() {
2522 // These checks need to be done after FileMapInfo::initialize(), which gets called before Universe::heap()
2523 // is available.
2524 if (header()->has_aot_linked_classes()) {
2525 CDSConfig::set_has_aot_linked_classes(is_static(), true);
2526 if (JvmtiExport::should_post_class_file_load_hook()) {
2527 log_error(cds)("CDS archive has aot-linked classes. It cannot be used when JVMTI ClassFileLoadHook is in use.");
2528 return false;
2529 }
2530 if (JvmtiExport::has_early_vmstart_env()) {
2531 log_error(cds)("CDS archive has aot-linked classes. It cannot be used when JVMTI early vm start is in use.");
2532 return false;
2533 }
2534 if (!CDSConfig::is_using_full_module_graph() && !CDSConfig::is_dumping_final_static_archive()) {
2535 log_error(cds)("CDS archive has aot-linked classes. It cannot be used when archived full module graph is not used.");
2536 return false;
2537 }
2538 if (header()->gc_kind() != (int)Universe::heap()->kind()) {
2539 log_error(cds)("CDS archive has aot-linked classes. It cannot be used because GC used during dump time (%s) is not the same as runtime (%s)",
2540 header()->gc_name(), Universe::heap()->name());
2541 return false;
2542 }
2543 }
2544
2545 return true;
2546 }
2547
2548 // The 2 core spaces are RW->RO
2549 FileMapRegion* FileMapInfo::first_core_region() const {
2550 return region_at(MetaspaceShared::rw);
2551 }
2552
2553 FileMapRegion* FileMapInfo::last_core_region() const {
2554 return region_at(MetaspaceShared::ro);
2555 }
2556
2557 void FileMapInfo::print(outputStream* st) const {
2558 header()->print(st);
2559 if (!is_static()) {
2560 dynamic_header()->print(st);
2561 }
2562 }
2563
2564 void FileMapHeader::set_as_offset(char* p, size_t *offset) {
2565 *offset = ArchiveBuilder::current()->any_to_offset((address)p);
2566 }
2567
2568 int FileMapHeader::compute_crc() {
2569 char* start = (char*)this;
2570 // start computing from the field after _header_size to end of base archive name.
2571 char* buf = (char*)&(_generic_header._header_size) + sizeof(_generic_header._header_size);
2572 size_t sz = header_size() - (buf - start);
2573 int crc = ClassLoader::crc32(0, buf, (jint)sz);
2574 return crc;
2575 }
2576
2577 // This function should only be called during run time with UseSharedSpaces enabled.
2578 bool FileMapHeader::validate() {
2579 if (_obj_alignment != ObjectAlignmentInBytes) {
2580 log_info(cds)("The shared archive file's ObjectAlignmentInBytes of %d"
2581 " does not equal the current ObjectAlignmentInBytes of %d.",
2582 _obj_alignment, ObjectAlignmentInBytes);
2583 return false;
2584 }
2585 if (_compact_strings != CompactStrings) {
2586 log_info(cds)("The shared archive file's CompactStrings setting (%s)"
2587 " does not equal the current CompactStrings setting (%s).",
2588 _compact_strings ? "enabled" : "disabled",
2589 CompactStrings ? "enabled" : "disabled");
2590 return false;
2591 }
2592
2593 // This must be done after header validation because it might change the
2594 // header data
2595 const char* prop = Arguments::get_property("java.system.class.loader");
2596 if (prop != nullptr) {
2597 log_warning(cds)("Archived non-system classes are disabled because the "
2598 "java.system.class.loader property is specified (value = \"%s\"). "
2599 "To use archived non-system classes, this property must not be set", prop);
2600 _has_platform_or_app_classes = false;
2601 }
2602
2603
2604 if (!_verify_local && BytecodeVerificationLocal) {
2605 // we cannot load boot classes, so there's no point of using the CDS archive
2606 log_info(cds)("The shared archive file's BytecodeVerificationLocal setting (%s)"
2607 " does not equal the current BytecodeVerificationLocal setting (%s).",
2608 _verify_local ? "enabled" : "disabled",
2609 BytecodeVerificationLocal ? "enabled" : "disabled");
2610 return false;
2611 }
2612
2613 // For backwards compatibility, we don't check the BytecodeVerificationRemote setting
2614 // if the archive only contains system classes.
2615 if (_has_platform_or_app_classes
2616 && !_verify_remote // we didn't verify the archived platform/app classes
2617 && BytecodeVerificationRemote) { // but we want to verify all loaded platform/app classes
2618 log_info(cds)("The shared archive file was created with less restrictive "
2619 "verification setting than the current setting.");
2620 // Pretend that we didn't have any archived platform/app classes, so they won't be loaded
2621 // by SystemDictionaryShared.
2622 _has_platform_or_app_classes = false;
2623 }
2624
2625 // Java agents are allowed during run time. Therefore, the following condition is not
2626 // checked: (!_allow_archiving_with_java_agent && AllowArchivingWithJavaAgent)
2627 // Note: _allow_archiving_with_java_agent is set in the shared archive during dump time
2628 // while AllowArchivingWithJavaAgent is set during the current run.
2629 if (_allow_archiving_with_java_agent && !AllowArchivingWithJavaAgent) {
2630 log_warning(cds)("The setting of the AllowArchivingWithJavaAgent is different "
2631 "from the setting in the shared archive.");
2632 return false;
2633 }
2634
2635 if (_allow_archiving_with_java_agent) {
2636 log_warning(cds)("This archive was created with AllowArchivingWithJavaAgent. It should be used "
2637 "for testing purposes only and should not be used in a production environment");
2638 }
2639
2640 log_info(cds)("Archive was created with UseCompressedOops = %d, UseCompressedClassPointers = %d",
2641 compressed_oops(), compressed_class_pointers());
2642 if (compressed_oops() != UseCompressedOops || compressed_class_pointers() != UseCompressedClassPointers) {
2643 log_info(cds)("Unable to use shared archive.\nThe saved state of UseCompressedOops and UseCompressedClassPointers is "
2644 "different from runtime, CDS will be disabled.");
2645 return false;
2646 }
2647
2648 if (! _use_secondary_supers_table && UseSecondarySupersTable) {
2649 log_warning(cds)("The shared archive was created without UseSecondarySupersTable.");
2650 return false;
2651 }
2652
2653 if (!_use_optimized_module_handling && !CDSConfig::is_dumping_final_static_archive()) {
2654 CDSConfig::stop_using_optimized_module_handling();
2655 log_info(cds)("optimized module handling: disabled because archive was created without optimized module handling");
2656 }
2657
2658 if (is_static()) {
2659 // Only the static archive can contain the full module graph.
2660 if (!_has_full_module_graph) {
2661 CDSConfig::stop_using_full_module_graph("archive was created without full module graph");
2662 }
2663
2664 if (_has_archived_invokedynamic) {
2665 CDSConfig::set_has_archived_invokedynamic();
2666 }
2667 if (_has_archived_packages) {
2668 CDSConfig::set_is_loading_packages();
2669 }
2670 if (_has_archived_protection_domains) {
2671 CDSConfig::set_is_loading_protection_domains();
2672 }
2673 }
2674
2675 return true;
2676 }
2677
2678 bool FileMapInfo::validate_header() {
2679 if (!header()->validate()) {
2680 return false;
2681 }
2682 if (_is_static) {
2683 return true;
2684 } else {
2685 return DynamicArchive::validate(this);
2686 }
2687 }
2688
2689 #if INCLUDE_JVMTI
2690 ClassPathEntry** FileMapInfo::_classpath_entries_for_jvmti = nullptr;
2691
2692 ClassPathEntry* FileMapInfo::get_classpath_entry_for_jvmti(int i, TRAPS) {
2693 if (i == 0) {
2694 // index 0 corresponds to the ClassPathImageEntry which is a globally shared object
2695 // and should never be deleted.
2696 return ClassLoader::get_jrt_entry();
2697 }
2698 ClassPathEntry* ent = _classpath_entries_for_jvmti[i];
2699 if (ent == nullptr) {
2700 SharedClassPathEntry* scpe = shared_path(i);
2701 assert(scpe->is_jar(), "must be"); // other types of scpe will not produce archived classes
2702
2703 const char* path = scpe->name();
2704 struct stat st;
2705 if (os::stat(path, &st) != 0) {
2706 char *msg = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, strlen(path) + 128);
2707 jio_snprintf(msg, strlen(path) + 127, "error in finding JAR file %s", path);
2708 THROW_MSG_(vmSymbols::java_io_IOException(), msg, nullptr);
2709 } else {
2710 ent = ClassLoader::create_class_path_entry(THREAD, path, &st, false, false);
2711 if (ent == nullptr) {
2712 char *msg = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, strlen(path) + 128);
2713 jio_snprintf(msg, strlen(path) + 127, "error in opening JAR file %s", path);
2714 THROW_MSG_(vmSymbols::java_io_IOException(), msg, nullptr);
2715 }
2716 }
2717
2718 MutexLocker mu(THREAD, CDSClassFileStream_lock);
2719 if (_classpath_entries_for_jvmti[i] == nullptr) {
2720 _classpath_entries_for_jvmti[i] = ent;
2721 } else {
2722 // Another thread has beat me to creating this entry
2723 delete ent;
2724 ent = _classpath_entries_for_jvmti[i];
2725 }
2726 }
2727
2728 return ent;
2729 }
2730
2731 ClassFileStream* FileMapInfo::open_stream_for_jvmti(InstanceKlass* ik, Handle class_loader, TRAPS) {
2732 int path_index = ik->shared_classpath_index();
2733 assert(path_index >= 0, "should be called for shared built-in classes only");
2734 assert(path_index < (int)get_number_of_shared_paths(), "sanity");
2735
2736 ClassPathEntry* cpe = get_classpath_entry_for_jvmti(path_index, CHECK_NULL);
2737 assert(cpe != nullptr, "must be");
2738
2739 Symbol* name = ik->name();
2740 const char* const class_name = name->as_C_string();
2741 const char* const file_name = ClassLoader::file_name_for_class_name(class_name,
2742 name->utf8_length());
2743 ClassLoaderData* loader_data = ClassLoaderData::class_loader_data(class_loader());
2744 ClassFileStream* cfs = cpe->open_stream_for_loader(THREAD, file_name, loader_data);
2745 assert(cfs != nullptr, "must be able to read the classfile data of shared classes for built-in loaders.");
2746 log_debug(cds, jvmti)("classfile data for %s [%d: %s] = %d bytes", class_name, path_index,
2747 cfs->source(), cfs->length());
2748 return cfs;
2749 }
2750
2751 #endif