1 /* 2 * Copyright (c) 2003, 2018, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "jvm.h" 27 #include "classfile/classLoader.inline.hpp" 28 #include "classfile/classLoaderExt.hpp" 29 #include "classfile/stringTable.hpp" 30 #include "classfile/symbolTable.hpp" 31 #include "classfile/systemDictionaryShared.hpp" 32 #include "classfile/altHashing.hpp" 33 #include "logging/log.hpp" 34 #include "logging/logStream.hpp" 35 #include "logging/logMessage.hpp" 36 #include "memory/filemap.hpp" 37 #include "memory/heapShared.inline.hpp" 38 #include "memory/iterator.inline.hpp" 39 #include "memory/metadataFactory.hpp" 40 #include "memory/metaspaceClosure.hpp" 41 #include "memory/metaspaceShared.hpp" 42 #include "memory/oopFactory.hpp" 43 #include "oops/compressedOops.inline.hpp" 44 #include "oops/objArrayOop.hpp" 45 #include "oops/oop.inline.hpp" 46 #include "prims/jvmtiExport.hpp" 47 #include "runtime/arguments.hpp" 48 #include "runtime/java.hpp" 49 #include "runtime/os.inline.hpp" 50 #include "runtime/vm_version.hpp" 51 #include "services/memTracker.hpp" 52 #include "utilities/align.hpp" 53 #include "utilities/defaultStream.hpp" 54 #if INCLUDE_G1GC 55 #include "gc/g1/g1CollectedHeap.hpp" 56 #include "gc/g1/heapRegion.hpp" 57 #endif 58 59 # include <sys/stat.h> 60 # include <errno.h> 61 62 #ifndef O_BINARY // if defined (Win32) use binary files. 63 #define O_BINARY 0 // otherwise do nothing. 64 #endif 65 66 extern address JVM_FunctionAtStart(); 67 extern address JVM_FunctionAtEnd(); 68 69 // Complain and stop. All error conditions occurring during the writing of 70 // an archive file should stop the process. Unrecoverable errors during 71 // the reading of the archive file should stop the process. 72 73 static void fail(const char *msg, va_list ap) { 74 // This occurs very early during initialization: tty is not initialized. 75 jio_fprintf(defaultStream::error_stream(), 76 "An error has occurred while processing the" 77 " shared archive file.\n"); 78 jio_vfprintf(defaultStream::error_stream(), msg, ap); 79 jio_fprintf(defaultStream::error_stream(), "\n"); 80 // Do not change the text of the below message because some tests check for it. 81 vm_exit_during_initialization("Unable to use shared archive.", NULL); 82 } 83 84 85 void FileMapInfo::fail_stop(const char *msg, ...) { 86 va_list ap; 87 va_start(ap, msg); 88 fail(msg, ap); // Never returns. 89 va_end(ap); // for completeness. 90 } 91 92 93 // Complain and continue. Recoverable errors during the reading of the 94 // archive file may continue (with sharing disabled). 95 // 96 // If we continue, then disable shared spaces and close the file. 97 98 void FileMapInfo::fail_continue(const char *msg, ...) { 99 va_list ap; 100 va_start(ap, msg); 101 MetaspaceShared::set_archive_loading_failed(); 102 if (PrintSharedArchiveAndExit && _validating_shared_path_table) { 103 // If we are doing PrintSharedArchiveAndExit and some of the classpath entries 104 // do not validate, we can still continue "limping" to validate the remaining 105 // entries. No need to quit. 106 tty->print("["); 107 tty->vprint(msg, ap); 108 tty->print_cr("]"); 109 } else { 110 if (RequireSharedSpaces) { 111 fail(msg, ap); 112 } else { 113 if (log_is_enabled(Info, cds)) { 114 ResourceMark rm; 115 LogStream ls(Log(cds)::info()); 116 ls.print("UseSharedSpaces: "); 117 ls.vprint_cr(msg, ap); 118 } 119 } 120 UseSharedSpaces = false; 121 assert(current_info() != NULL, "singleton must be registered"); 122 current_info()->close(); 123 } 124 va_end(ap); 125 } 126 127 // Fill in the fileMapInfo structure with data about this VM instance. 128 129 // This method copies the vm version info into header_version. If the version is too 130 // long then a truncated version, which has a hash code appended to it, is copied. 131 // 132 // Using a template enables this method to verify that header_version is an array of 133 // length JVM_IDENT_MAX. This ensures that the code that writes to the CDS file and 134 // the code that reads the CDS file will both use the same size buffer. Hence, will 135 // use identical truncation. This is necessary for matching of truncated versions. 136 template <int N> static void get_header_version(char (&header_version) [N]) { 137 assert(N == JVM_IDENT_MAX, "Bad header_version size"); 138 139 const char *vm_version = VM_Version::internal_vm_info_string(); 140 const int version_len = (int)strlen(vm_version); 141 142 if (version_len < (JVM_IDENT_MAX-1)) { 143 strcpy(header_version, vm_version); 144 145 } else { 146 // Get the hash value. Use a static seed because the hash needs to return the same 147 // value over multiple jvm invocations. 148 unsigned int hash = AltHashing::murmur3_32(8191, (const jbyte*)vm_version, version_len); 149 150 // Truncate the ident, saving room for the 8 hex character hash value. 151 strncpy(header_version, vm_version, JVM_IDENT_MAX-9); 152 153 // Append the hash code as eight hex digits. 154 sprintf(&header_version[JVM_IDENT_MAX-9], "%08x", hash); 155 header_version[JVM_IDENT_MAX-1] = 0; // Null terminate. 156 } 157 } 158 159 FileMapInfo::FileMapInfo() { 160 assert(_current_info == NULL, "must be singleton"); // not thread safe 161 _current_info = this; 162 memset((void*)this, 0, sizeof(FileMapInfo)); 163 _file_offset = 0; 164 _file_open = false; 165 _header = (FileMapHeader*)os::malloc(sizeof(FileMapHeader), mtInternal); 166 _header->_version = INVALID_CDS_ARCHIVE_VERSION; 167 _header->_has_platform_or_app_classes = true; 168 } 169 170 FileMapInfo::~FileMapInfo() { 171 assert(_current_info == this, "must be singleton"); // not thread safe 172 _current_info = NULL; 173 } 174 175 void FileMapInfo::populate_header(size_t alignment) { 176 _header->populate(this, alignment); 177 } 178 179 void FileMapHeader::populate(FileMapInfo* mapinfo, size_t alignment) { 180 _magic = CDS_ARCHIVE_MAGIC; 181 _version = CURRENT_CDS_ARCHIVE_VERSION; 182 _alignment = alignment; 183 _obj_alignment = ObjectAlignmentInBytes; 184 _compact_strings = CompactStrings; 185 _narrow_oop_mode = Universe::narrow_oop_mode(); 186 _narrow_oop_base = Universe::narrow_oop_base(); 187 _narrow_oop_shift = Universe::narrow_oop_shift(); 188 _max_heap_size = MaxHeapSize; 189 _narrow_klass_base = Universe::narrow_klass_base(); 190 _narrow_klass_shift = Universe::narrow_klass_shift(); 191 _shared_path_table_size = mapinfo->_shared_path_table_size; 192 _shared_path_table = mapinfo->_shared_path_table; 193 _shared_path_entry_size = mapinfo->_shared_path_entry_size; 194 if (HeapShared::is_heap_object_archiving_allowed()) { 195 _heap_reserved = Universe::heap()->reserved_region(); 196 } 197 198 // The following fields are for sanity checks for whether this archive 199 // will function correctly with this JVM and the bootclasspath it's 200 // invoked with. 201 202 // JVM version string ... changes on each build. 203 get_header_version(_jvm_ident); 204 205 ClassLoaderExt::finalize_shared_paths_misc_info(); 206 _app_class_paths_start_index = ClassLoaderExt::app_class_paths_start_index(); 207 _app_module_paths_start_index = ClassLoaderExt::app_module_paths_start_index(); 208 _max_used_path_index = ClassLoaderExt::max_used_path_index(); 209 210 _verify_local = BytecodeVerificationLocal; 211 _verify_remote = BytecodeVerificationRemote; 212 _has_platform_or_app_classes = ClassLoaderExt::has_platform_or_app_classes(); 213 } 214 215 void SharedClassPathEntry::init(const char* name, bool is_modules_image, TRAPS) { 216 assert(DumpSharedSpaces, "dump time only"); 217 _timestamp = 0; 218 _filesize = 0; 219 220 struct stat st; 221 if (os::stat(name, &st) == 0) { 222 if ((st.st_mode & S_IFMT) == S_IFDIR) { 223 _type = dir_entry; 224 } else { 225 // The timestamp of the modules_image is not checked at runtime. 226 if (is_modules_image) { 227 _type = modules_image_entry; 228 } else { 229 _type = jar_entry; 230 _timestamp = st.st_mtime; 231 } 232 _filesize = st.st_size; 233 } 234 } else { 235 // The file/dir must exist, or it would not have been added 236 // into ClassLoader::classpath_entry(). 237 // 238 // If we can't access a jar file in the boot path, then we can't 239 // make assumptions about where classes get loaded from. 240 FileMapInfo::fail_stop("Unable to open file %s.", name); 241 } 242 243 size_t len = strlen(name) + 1; 244 _name = MetadataFactory::new_array<char>(ClassLoaderData::the_null_class_loader_data(), (int)len, THREAD); 245 strcpy(_name->data(), name); 246 } 247 248 bool SharedClassPathEntry::validate(bool is_class_path) { 249 assert(UseSharedSpaces, "runtime only"); 250 251 struct stat st; 252 const char* name; 253 254 // In order to validate the runtime modules image file size against the archived 255 // size information, we need to obtain the runtime modules image path. The recorded 256 // dump time modules image path in the archive may be different from the runtime path 257 // if the JDK image has beed moved after generating the archive. 258 if (is_modules_image()) { 259 name = ClassLoader::get_jrt_entry()->name(); 260 } else { 261 name = this->name(); 262 } 263 264 bool ok = true; 265 log_info(class, path)("checking shared classpath entry: %s", name); 266 if (os::stat(name, &st) != 0 && is_class_path) { 267 // If the archived module path entry does not exist at runtime, it is not fatal 268 // (no need to invalid the shared archive) because the shared runtime visibility check 269 // filters out any archived module classes that do not have a matching runtime 270 // module path location. 271 FileMapInfo::fail_continue("Required classpath entry does not exist: %s", name); 272 ok = false; 273 } else if (is_dir()) { 274 if (!os::dir_is_empty(name)) { 275 FileMapInfo::fail_continue("directory is not empty: %s", name); 276 ok = false; 277 } 278 } else if ((has_timestamp() && _timestamp != st.st_mtime) || 279 _filesize != st.st_size) { 280 ok = false; 281 if (PrintSharedArchiveAndExit) { 282 FileMapInfo::fail_continue(_timestamp != st.st_mtime ? 283 "Timestamp mismatch" : 284 "File size mismatch"); 285 } else { 286 FileMapInfo::fail_continue("A jar file is not the one used while building" 287 " the shared archive file: %s", name); 288 } 289 } 290 return ok; 291 } 292 293 void SharedClassPathEntry::metaspace_pointers_do(MetaspaceClosure* it) { 294 it->push(&_name); 295 it->push(&_manifest); 296 } 297 298 void FileMapInfo::allocate_shared_path_table() { 299 assert(DumpSharedSpaces, "Sanity"); 300 301 Thread* THREAD = Thread::current(); 302 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data(); 303 ClassPathEntry* jrt = ClassLoader::get_jrt_entry(); 304 305 assert(jrt != NULL, 306 "No modular java runtime image present when allocating the CDS classpath entry table"); 307 308 size_t entry_size = sizeof(SharedClassPathEntry); // assert ( should be 8 byte aligned??) 309 int num_boot_classpath_entries = ClassLoader::num_boot_classpath_entries(); 310 int num_app_classpath_entries = ClassLoader::num_app_classpath_entries(); 311 int num_module_path_entries = ClassLoader::num_module_path_entries(); 312 int num_entries = num_boot_classpath_entries + num_app_classpath_entries + num_module_path_entries; 313 size_t bytes = entry_size * num_entries; 314 315 _shared_path_table = MetadataFactory::new_array<u8>(loader_data, (int)(bytes + 7 / 8), THREAD); 316 _shared_path_table_size = num_entries; 317 _shared_path_entry_size = entry_size; 318 319 // 1. boot class path 320 int i = 0; 321 ClassPathEntry* cpe = jrt; 322 while (cpe != NULL) { 323 bool is_jrt = (cpe == jrt); 324 const char* type = (is_jrt ? "jrt" : (cpe->is_jar_file() ? "jar" : "dir")); 325 log_info(class, path)("add main shared path (%s) %s", type, cpe->name()); 326 SharedClassPathEntry* ent = shared_path(i); 327 ent->init(cpe->name(), is_jrt, THREAD); 328 if (!is_jrt) { // No need to do the modules image. 329 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error. 330 update_shared_classpath(cpe, ent, THREAD); 331 } 332 cpe = ClassLoader::get_next_boot_classpath_entry(cpe); 333 i++; 334 } 335 assert(i == num_boot_classpath_entries, 336 "number of boot class path entry mismatch"); 337 338 // 2. app class path 339 ClassPathEntry *acpe = ClassLoader::app_classpath_entries(); 340 while (acpe != NULL) { 341 log_info(class, path)("add app shared path %s", acpe->name()); 342 SharedClassPathEntry* ent = shared_path(i); 343 ent->init(acpe->name(), false, THREAD); 344 EXCEPTION_MARK; 345 update_shared_classpath(acpe, ent, THREAD); 346 acpe = acpe->next(); 347 i++; 348 } 349 350 // 3. module path 351 ClassPathEntry *mpe = ClassLoader::module_path_entries(); 352 while (mpe != NULL) { 353 log_info(class, path)("add module path %s",mpe->name()); 354 SharedClassPathEntry* ent = shared_path(i); 355 ent->init(mpe->name(), false, THREAD); 356 EXCEPTION_MARK; 357 update_shared_classpath(mpe, ent, THREAD); 358 mpe = mpe->next(); 359 i++; 360 } 361 assert(i == num_entries, "number of shared path entry mismatch"); 362 } 363 364 void FileMapInfo::check_nonempty_dir_in_shared_path_table() { 365 assert(DumpSharedSpaces, "dump time only"); 366 367 bool has_nonempty_dir = false; 368 369 int last = _shared_path_table_size - 1; 370 if (last > ClassLoaderExt::max_used_path_index()) { 371 // no need to check any path beyond max_used_path_index 372 last = ClassLoaderExt::max_used_path_index(); 373 } 374 375 for (int i = 0; i <= last; i++) { 376 SharedClassPathEntry *e = shared_path(i); 377 if (e->is_dir()) { 378 const char* path = e->name(); 379 if (!os::dir_is_empty(path)) { 380 tty->print_cr("Error: non-empty directory '%s'", path); 381 has_nonempty_dir = true; 382 } 383 } 384 } 385 386 if (has_nonempty_dir) { 387 ClassLoader::exit_with_path_failure("Cannot have non-empty directory in paths", NULL); 388 } 389 } 390 391 class ManifestStream: public ResourceObj { 392 private: 393 u1* _buffer_start; // Buffer bottom 394 u1* _buffer_end; // Buffer top (one past last element) 395 u1* _current; // Current buffer position 396 397 public: 398 // Constructor 399 ManifestStream(u1* buffer, int length) : _buffer_start(buffer), 400 _current(buffer) { 401 _buffer_end = buffer + length; 402 } 403 404 static bool is_attr(u1* attr, const char* name) { 405 return strncmp((const char*)attr, name, strlen(name)) == 0; 406 } 407 408 static char* copy_attr(u1* value, size_t len) { 409 char* buf = NEW_RESOURCE_ARRAY(char, len + 1); 410 strncpy(buf, (char*)value, len); 411 buf[len] = 0; 412 return buf; 413 } 414 415 // The return value indicates if the JAR is signed or not 416 bool check_is_signed() { 417 u1* attr = _current; 418 bool isSigned = false; 419 while (_current < _buffer_end) { 420 if (*_current == '\n') { 421 *_current = '\0'; 422 u1* value = (u1*)strchr((char*)attr, ':'); 423 if (value != NULL) { 424 assert(*(value+1) == ' ', "Unrecognized format" ); 425 if (strstr((char*)attr, "-Digest") != NULL) { 426 isSigned = true; 427 break; 428 } 429 } 430 *_current = '\n'; // restore 431 attr = _current + 1; 432 } 433 _current ++; 434 } 435 return isSigned; 436 } 437 }; 438 439 void FileMapInfo::update_shared_classpath(ClassPathEntry *cpe, SharedClassPathEntry* ent, TRAPS) { 440 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data(); 441 ResourceMark rm(THREAD); 442 jint manifest_size; 443 444 if (cpe->is_jar_file()) { 445 assert(ent->is_jar(), "the shared class path entry is not a JAR file"); 446 char* manifest = ClassLoaderExt::read_manifest(cpe, &manifest_size, CHECK); 447 if (manifest != NULL) { 448 ManifestStream* stream = new ManifestStream((u1*)manifest, 449 manifest_size); 450 if (stream->check_is_signed()) { 451 ent->set_is_signed(); 452 } else { 453 // Copy the manifest into the shared archive 454 manifest = ClassLoaderExt::read_raw_manifest(cpe, &manifest_size, CHECK); 455 Array<u1>* buf = MetadataFactory::new_array<u1>(loader_data, 456 manifest_size, 457 THREAD); 458 char* p = (char*)(buf->data()); 459 memcpy(p, manifest, manifest_size); 460 ent->set_manifest(buf); 461 } 462 } 463 } 464 } 465 466 467 bool FileMapInfo::validate_shared_path_table() { 468 assert(UseSharedSpaces, "runtime only"); 469 470 _validating_shared_path_table = true; 471 _shared_path_table = _header->_shared_path_table; 472 _shared_path_entry_size = _header->_shared_path_entry_size; 473 _shared_path_table_size = _header->_shared_path_table_size; 474 475 int module_paths_start_index = _header->_app_module_paths_start_index; 476 477 // validate the path entries up to the _max_used_path_index 478 for (int i=0; i < _header->_max_used_path_index + 1; i++) { 479 if (i < module_paths_start_index) { 480 if (shared_path(i)->validate()) { 481 log_info(class, path)("ok"); 482 } 483 } else if (i >= module_paths_start_index) { 484 if (shared_path(i)->validate(false /* not a class path entry */)) { 485 log_info(class, path)("ok"); 486 } 487 } else if (!PrintSharedArchiveAndExit) { 488 _validating_shared_path_table = false; 489 _shared_path_table = NULL; 490 _shared_path_table_size = 0; 491 return false; 492 } 493 } 494 495 _validating_shared_path_table = false; 496 return true; 497 } 498 499 // Read the FileMapInfo information from the file. 500 501 bool FileMapInfo::init_from_file(int fd) { 502 size_t sz = sizeof(FileMapHeader); 503 size_t n = os::read(fd, _header, (unsigned int)sz); 504 if (n != sz) { 505 fail_continue("Unable to read the file header."); 506 return false; 507 } 508 if (_header->_version != CURRENT_CDS_ARCHIVE_VERSION) { 509 fail_continue("The shared archive file has the wrong version."); 510 return false; 511 } 512 _file_offset = (long)n; 513 514 size_t info_size = _header->_paths_misc_info_size; 515 _paths_misc_info = NEW_C_HEAP_ARRAY_RETURN_NULL(char, info_size, mtClass); 516 if (_paths_misc_info == NULL) { 517 fail_continue("Unable to read the file header."); 518 return false; 519 } 520 n = os::read(fd, _paths_misc_info, (unsigned int)info_size); 521 if (n != info_size) { 522 fail_continue("Unable to read the shared path info header."); 523 FREE_C_HEAP_ARRAY(char, _paths_misc_info); 524 _paths_misc_info = NULL; 525 return false; 526 } 527 528 size_t len = lseek(fd, 0, SEEK_END); 529 CDSFileMapRegion* si = space_at(MetaspaceShared::last_valid_region); 530 // The last space might be empty 531 if (si->_file_offset > len || len - si->_file_offset < si->_used) { 532 fail_continue("The shared archive file has been truncated."); 533 return false; 534 } 535 536 _file_offset += (long)n; 537 return true; 538 } 539 540 541 // Read the FileMapInfo information from the file. 542 bool FileMapInfo::open_for_read() { 543 _full_path = Arguments::GetSharedArchivePath(); 544 int fd = open(_full_path, O_RDONLY | O_BINARY, 0); 545 if (fd < 0) { 546 if (errno == ENOENT) { 547 // Not locating the shared archive is ok. 548 fail_continue("Specified shared archive not found."); 549 } else { 550 fail_continue("Failed to open shared archive file (%s).", 551 os::strerror(errno)); 552 } 553 return false; 554 } 555 556 _fd = fd; 557 _file_open = true; 558 return true; 559 } 560 561 562 // Write the FileMapInfo information to the file. 563 564 void FileMapInfo::open_for_write() { 565 _full_path = Arguments::GetSharedArchivePath(); 566 LogMessage(cds) msg; 567 if (msg.is_info()) { 568 msg.info("Dumping shared data to file: "); 569 msg.info(" %s", _full_path); 570 } 571 572 #ifdef _WINDOWS // On Windows, need WRITE permission to remove the file. 573 chmod(_full_path, _S_IREAD | _S_IWRITE); 574 #endif 575 576 // Use remove() to delete the existing file because, on Unix, this will 577 // allow processes that have it open continued access to the file. 578 remove(_full_path); 579 int fd = open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444); 580 if (fd < 0) { 581 fail_stop("Unable to create shared archive file %s: (%s).", _full_path, 582 os::strerror(errno)); 583 } 584 _fd = fd; 585 _file_offset = 0; 586 _file_open = true; 587 } 588 589 590 // Write the header to the file, seek to the next allocation boundary. 591 592 void FileMapInfo::write_header() { 593 int info_size = ClassLoader::get_shared_paths_misc_info_size(); 594 595 _header->_paths_misc_info_size = info_size; 596 597 align_file_position(); 598 write_bytes(_header, sizeof(FileMapHeader)); 599 write_bytes(ClassLoader::get_shared_paths_misc_info(), (size_t)info_size); 600 align_file_position(); 601 } 602 603 604 // Dump region to file. 605 606 void FileMapInfo::write_region(int region, char* base, size_t size, 607 bool read_only, bool allow_exec) { 608 CDSFileMapRegion* si = space_at(region); 609 610 if (_file_open) { 611 guarantee(si->_file_offset == _file_offset, "file offset mismatch."); 612 log_info(cds)("Shared file region %d: " SIZE_FORMAT_HEX_W(08) 613 " bytes, addr " INTPTR_FORMAT " file offset " SIZE_FORMAT_HEX_W(08), 614 region, size, p2i(base), _file_offset); 615 } else { 616 si->_file_offset = _file_offset; 617 } 618 if (MetaspaceShared::is_heap_region(region)) { 619 assert((base - (char*)Universe::narrow_oop_base()) % HeapWordSize == 0, "Sanity"); 620 if (base != NULL) { 621 si->_addr._offset = (intx)CompressedOops::encode_not_null((oop)base); 622 } else { 623 si->_addr._offset = 0; 624 } 625 } else { 626 si->_addr._base = base; 627 } 628 si->_used = size; 629 si->_read_only = read_only; 630 si->_allow_exec = allow_exec; 631 si->_crc = ClassLoader::crc32(0, base, (jint)size); 632 if (base != NULL) { 633 write_bytes_aligned(base, size); 634 } 635 } 636 637 // Write out the given archive heap memory regions. GC code combines multiple 638 // consecutive archive GC regions into one MemRegion whenever possible and 639 // produces the 'heap_mem' array. 640 // 641 // If the archive heap memory size is smaller than a single dump time GC region 642 // size, there is only one MemRegion in the array. 643 // 644 // If the archive heap memory size is bigger than one dump time GC region size, 645 // the 'heap_mem' array may contain more than one consolidated MemRegions. When 646 // the first/bottom archive GC region is a partial GC region (with the empty 647 // portion at the higher address within the region), one MemRegion is used for 648 // the bottom partial archive GC region. The rest of the consecutive archive 649 // GC regions are combined into another MemRegion. 650 // 651 // Here's the mapping from (archive heap GC regions) -> (GrowableArray<MemRegion> *regions). 652 // + We have 1 or more archive heap regions: ah0, ah1, ah2 ..... ahn 653 // + We have 1 or 2 consolidated heap memory regions: r0 and r1 654 // 655 // If there's a single archive GC region (ah0), then r0 == ah0, and r1 is empty. 656 // Otherwise: 657 // 658 // "X" represented space that's occupied by heap objects. 659 // "_" represented unused spaced in the heap region. 660 // 661 // 662 // |ah0 | ah1 | ah2| ...... | ahn| 663 // |XXXXXX|__ |XXXXX|XXXX|XXXXXXXX|XXXX| 664 // |<-r0->| |<- r1 ----------------->| 665 // ^^^ 666 // | 667 // +-- gap 668 size_t FileMapInfo::write_archive_heap_regions(GrowableArray<MemRegion> *heap_mem, 669 GrowableArray<ArchiveHeapOopmapInfo> *oopmaps, 670 int first_region_id, int max_num_regions) { 671 assert(max_num_regions <= 2, "Only support maximum 2 memory regions"); 672 673 int arr_len = heap_mem == NULL ? 0 : heap_mem->length(); 674 if(arr_len > max_num_regions) { 675 fail_stop("Unable to write archive heap memory regions: " 676 "number of memory regions exceeds maximum due to fragmentation"); 677 } 678 679 size_t total_size = 0; 680 for (int i = first_region_id, arr_idx = 0; 681 i < first_region_id + max_num_regions; 682 i++, arr_idx++) { 683 char* start = NULL; 684 size_t size = 0; 685 if (arr_idx < arr_len) { 686 start = (char*)heap_mem->at(arr_idx).start(); 687 size = heap_mem->at(arr_idx).byte_size(); 688 total_size += size; 689 } 690 691 log_info(cds)("Archive heap region %d " INTPTR_FORMAT " - " INTPTR_FORMAT " = " SIZE_FORMAT_W(8) " bytes", 692 i, p2i(start), p2i(start + size), size); 693 write_region(i, start, size, false, false); 694 if (size > 0) { 695 space_at(i)->_oopmap = oopmaps->at(arr_idx)._oopmap; 696 space_at(i)->_oopmap_size_in_bits = oopmaps->at(arr_idx)._oopmap_size_in_bits; 697 } 698 } 699 return total_size; 700 } 701 702 // Dump bytes to file -- at the current file position. 703 704 void FileMapInfo::write_bytes(const void* buffer, size_t nbytes) { 705 if (_file_open) { 706 size_t n = os::write(_fd, buffer, (unsigned int)nbytes); 707 if (n != nbytes) { 708 // It is dangerous to leave the corrupted shared archive file around, 709 // close and remove the file. See bug 6372906. 710 close(); 711 remove(_full_path); 712 fail_stop("Unable to write to shared archive file."); 713 } 714 } 715 _file_offset += nbytes; 716 } 717 718 719 // Align file position to an allocation unit boundary. 720 721 void FileMapInfo::align_file_position() { 722 size_t new_file_offset = align_up(_file_offset, 723 os::vm_allocation_granularity()); 724 if (new_file_offset != _file_offset) { 725 _file_offset = new_file_offset; 726 if (_file_open) { 727 // Seek one byte back from the target and write a byte to insure 728 // that the written file is the correct length. 729 _file_offset -= 1; 730 if (lseek(_fd, (long)_file_offset, SEEK_SET) < 0) { 731 fail_stop("Unable to seek."); 732 } 733 char zero = 0; 734 write_bytes(&zero, 1); 735 } 736 } 737 } 738 739 740 // Dump bytes to file -- at the current file position. 741 742 void FileMapInfo::write_bytes_aligned(const void* buffer, size_t nbytes) { 743 align_file_position(); 744 write_bytes(buffer, nbytes); 745 align_file_position(); 746 } 747 748 749 // Close the shared archive file. This does NOT unmap mapped regions. 750 751 void FileMapInfo::close() { 752 if (_file_open) { 753 if (::close(_fd) < 0) { 754 fail_stop("Unable to close the shared archive file."); 755 } 756 _file_open = false; 757 _fd = -1; 758 } 759 } 760 761 762 // JVM/TI RedefineClasses() support: 763 // Remap the shared readonly space to shared readwrite, private. 764 bool FileMapInfo::remap_shared_readonly_as_readwrite() { 765 int idx = MetaspaceShared::ro; 766 CDSFileMapRegion* si = space_at(idx); 767 if (!si->_read_only) { 768 // the space is already readwrite so we are done 769 return true; 770 } 771 size_t used = si->_used; 772 size_t size = align_up(used, os::vm_allocation_granularity()); 773 if (!open_for_read()) { 774 return false; 775 } 776 char *addr = region_addr(idx); 777 char *base = os::remap_memory(_fd, _full_path, si->_file_offset, 778 addr, size, false /* !read_only */, 779 si->_allow_exec); 780 close(); 781 if (base == NULL) { 782 fail_continue("Unable to remap shared readonly space (errno=%d).", errno); 783 return false; 784 } 785 if (base != addr) { 786 fail_continue("Unable to remap shared readonly space at required address."); 787 return false; 788 } 789 si->_read_only = false; 790 return true; 791 } 792 793 // Map the whole region at once, assumed to be allocated contiguously. 794 ReservedSpace FileMapInfo::reserve_shared_memory() { 795 char* requested_addr = region_addr(0); 796 size_t size = FileMapInfo::core_spaces_size(); 797 798 // Reserve the space first, then map otherwise map will go right over some 799 // other reserved memory (like the code cache). 800 ReservedSpace rs(size, os::vm_allocation_granularity(), false, requested_addr); 801 if (!rs.is_reserved()) { 802 fail_continue("Unable to reserve shared space at required address " 803 INTPTR_FORMAT, p2i(requested_addr)); 804 return rs; 805 } 806 // the reserved virtual memory is for mapping class data sharing archive 807 MemTracker::record_virtual_memory_type((address)rs.base(), mtClassShared); 808 809 return rs; 810 } 811 812 // Memory map a region in the address space. 813 static const char* shared_region_name[] = { "MiscData", "ReadWrite", "ReadOnly", "MiscCode", "OptionalData", 814 "String1", "String2", "OpenArchive1", "OpenArchive2" }; 815 816 char* FileMapInfo::map_region(int i, char** top_ret) { 817 assert(!MetaspaceShared::is_heap_region(i), "sanity"); 818 CDSFileMapRegion* si = space_at(i); 819 size_t used = si->_used; 820 size_t alignment = os::vm_allocation_granularity(); 821 size_t size = align_up(used, alignment); 822 char *requested_addr = region_addr(i); 823 824 // If a tool agent is in use (debugging enabled), we must map the address space RW 825 if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space()) { 826 si->_read_only = false; 827 } 828 829 // map the contents of the CDS archive in this memory 830 char *base = os::map_memory(_fd, _full_path, si->_file_offset, 831 requested_addr, size, si->_read_only, 832 si->_allow_exec); 833 if (base == NULL || base != requested_addr) { 834 fail_continue("Unable to map %s shared space at required address.", shared_region_name[i]); 835 return NULL; 836 } 837 #ifdef _WINDOWS 838 // This call is Windows-only because the memory_type gets recorded for the other platforms 839 // in method FileMapInfo::reserve_shared_memory(), which is not called on Windows. 840 MemTracker::record_virtual_memory_type((address)base, mtClassShared); 841 #endif 842 843 844 if (!verify_region_checksum(i)) { 845 return NULL; 846 } 847 848 *top_ret = base + size; 849 return base; 850 } 851 852 address FileMapInfo::decode_start_address(CDSFileMapRegion* spc, bool with_current_oop_encoding_mode) { 853 if (with_current_oop_encoding_mode) { 854 return (address)CompressedOops::decode_not_null(offset_of_space(spc)); 855 } else { 856 return (address)HeapShared::decode_from_archive(offset_of_space(spc)); 857 } 858 } 859 860 static MemRegion *string_ranges = NULL; 861 static MemRegion *open_archive_heap_ranges = NULL; 862 static int num_string_ranges = 0; 863 static int num_open_archive_heap_ranges = 0; 864 865 #if INCLUDE_CDS_JAVA_HEAP 866 bool FileMapInfo::has_heap_regions() { 867 return (_header->_space[MetaspaceShared::first_string]._used > 0); 868 } 869 870 // Returns the address range of the archived heap regions computed using the 871 // current oop encoding mode. This range may be different than the one seen at 872 // dump time due to encoding mode differences. The result is used in determining 873 // if/how these regions should be relocated at run time. 874 MemRegion FileMapInfo::get_heap_regions_range_with_current_oop_encoding_mode() { 875 address start = (address) max_uintx; 876 address end = NULL; 877 878 for (int i = MetaspaceShared::first_string; i <= MetaspaceShared::last_valid_region; i++) { 879 CDSFileMapRegion* si = space_at(i); 880 size_t size = si->_used; 881 if (size > 0) { 882 address s = start_address_as_decoded_with_current_oop_encoding_mode(si); 883 address e = s + size; 884 if (start > s) { 885 start = s; 886 } 887 if (end < e) { 888 end = e; 889 } 890 } 891 } 892 assert(end != NULL, "must have at least one used heap region"); 893 return MemRegion((HeapWord*)start, (HeapWord*)end); 894 } 895 896 // 897 // Map the shared string objects and open archive heap objects to the runtime 898 // java heap. 899 // 900 // The shared strings are mapped close to the end of the java heap top in 901 // closed archive regions. The mapped strings contain no out-going references 902 // to any other java heap regions. GC does not write into the mapped shared strings. 903 // 904 // The open archive heap objects are mapped below the shared strings in 905 // the runtime java heap. The mapped open archive heap data only contain 906 // references to the shared strings and open archive objects initially. 907 // During runtime execution, out-going references to any other java heap 908 // regions may be added. GC may mark and update references in the mapped 909 // open archive objects. 910 void FileMapInfo::map_heap_regions_impl() { 911 if (!HeapShared::is_heap_object_archiving_allowed()) { 912 log_info(cds)("CDS heap data is being ignored. UseG1GC, " 913 "UseCompressedOops and UseCompressedClassPointers are required."); 914 return; 915 } 916 917 MemRegion heap_reserved = Universe::heap()->reserved_region(); 918 919 log_info(cds)("CDS archive was created with max heap size = " SIZE_FORMAT "M, and the following configuration:", 920 max_heap_size()/M); 921 log_info(cds)(" narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d", 922 p2i(narrow_klass_base()), narrow_klass_shift()); 923 log_info(cds)(" narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d", 924 narrow_oop_mode(), p2i(narrow_oop_base()), narrow_oop_shift()); 925 926 log_info(cds)("The current max heap size = " SIZE_FORMAT "M, HeapRegion::GrainBytes = " SIZE_FORMAT, 927 heap_reserved.byte_size()/M, HeapRegion::GrainBytes); 928 log_info(cds)(" narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d", 929 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift()); 930 log_info(cds)(" narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d", 931 Universe::narrow_oop_mode(), p2i(Universe::narrow_oop_base()), Universe::narrow_oop_shift()); 932 933 if (narrow_klass_base() != Universe::narrow_klass_base() || 934 narrow_klass_shift() != Universe::narrow_klass_shift()) { 935 log_info(cds)("CDS heap data cannot be used because the archive was created with an incompatible narrow klass encoding mode."); 936 return; 937 } 938 939 if (narrow_oop_mode() != Universe::narrow_oop_mode() || 940 narrow_oop_base() != Universe::narrow_oop_base() || 941 narrow_oop_shift() != Universe::narrow_oop_shift()) { 942 log_info(cds)("CDS heap data need to be relocated because the archive was created with an incompatible oop encoding mode."); 943 _heap_pointers_need_patching = true; 944 } else { 945 MemRegion range = get_heap_regions_range_with_current_oop_encoding_mode(); 946 if (!heap_reserved.contains(range)) { 947 log_info(cds)("CDS heap data need to be relocated because"); 948 log_info(cds)("the desired range " PTR_FORMAT " - " PTR_FORMAT, p2i(range.start()), p2i(range.end())); 949 log_info(cds)("is outside of the heap " PTR_FORMAT " - " PTR_FORMAT, p2i(heap_reserved.start()), p2i(heap_reserved.end())); 950 _heap_pointers_need_patching = true; 951 } 952 } 953 954 ptrdiff_t delta = 0; 955 if (_heap_pointers_need_patching) { 956 // dumptime heap end ------------v 957 // [ |archived heap regions| ] runtime heap end ------v 958 // [ |archived heap regions| ] 959 // |<-----delta-------------------->| 960 // 961 // At dump time, the archived heap regions were near the top of the heap. 962 // At run time, they may not be inside the heap, so we move them so 963 // that they are now near the top of the runtime time. This can be done by 964 // the simple math of adding the delta as shown above. 965 address dumptime_heap_end = (address)_header->_heap_reserved.end(); 966 address runtime_heap_end = (address)heap_reserved.end(); 967 delta = runtime_heap_end - dumptime_heap_end; 968 } 969 970 log_info(cds)("CDS heap data relocation delta = " INTX_FORMAT " bytes", delta); 971 HeapShared::init_narrow_oop_decoding(narrow_oop_base() + delta, narrow_oop_shift()); 972 973 CDSFileMapRegion* si = space_at(MetaspaceShared::first_string); 974 address relocated_strings_bottom = start_address_as_decoded_from_archive(si); 975 if (!is_aligned(relocated_strings_bottom, HeapRegion::GrainBytes)) { 976 // Align the bottom of the string regions at G1 region boundary. This will avoid 977 // the situation where the highest open region and the lowest string region sharing 978 // the same G1 region. Otherwise we will fail to map the open regions. 979 size_t align = size_t(relocated_strings_bottom) % HeapRegion::GrainBytes; 980 delta -= align; 981 log_info(cds)("CDS heap data need to be relocated lower by a further " SIZE_FORMAT 982 " bytes to " INTX_FORMAT " to be aligned with HeapRegion::GrainBytes", align, delta); 983 HeapShared::init_narrow_oop_decoding(narrow_oop_base() + delta, narrow_oop_shift()); 984 _heap_pointers_need_patching = true; 985 relocated_strings_bottom = start_address_as_decoded_from_archive(si); 986 } 987 assert(is_aligned(relocated_strings_bottom, HeapRegion::GrainBytes), "must be"); 988 989 // First, map string regions as closed archive heap regions. 990 // GC does not write into the regions. 991 if (map_heap_data(&string_ranges, 992 MetaspaceShared::first_string, 993 MetaspaceShared::max_strings, 994 &num_string_ranges)) { 995 StringTable::set_shared_string_mapped(); 996 997 // Now, map open_archive heap regions, GC can write into the regions. 998 if (map_heap_data(&open_archive_heap_ranges, 999 MetaspaceShared::first_open_archive_heap_region, 1000 MetaspaceShared::max_open_archive_heap_region, 1001 &num_open_archive_heap_ranges, 1002 true /* open */)) { 1003 HeapShared::set_open_archive_heap_region_mapped(); 1004 } 1005 } 1006 } 1007 1008 void FileMapInfo::map_heap_regions() { 1009 if (has_heap_regions()) { 1010 map_heap_regions_impl(); 1011 } 1012 1013 if (!StringTable::shared_string_mapped()) { 1014 assert(string_ranges == NULL && num_string_ranges == 0, "sanity"); 1015 } 1016 1017 if (!HeapShared::open_archive_heap_region_mapped()) { 1018 assert(open_archive_heap_ranges == NULL && num_open_archive_heap_ranges == 0, "sanity"); 1019 } 1020 } 1021 1022 bool FileMapInfo::map_heap_data(MemRegion **heap_mem, int first, 1023 int max, int* num, bool is_open_archive) { 1024 MemRegion * regions = new MemRegion[max]; 1025 CDSFileMapRegion* si; 1026 int region_num = 0; 1027 1028 for (int i = first; 1029 i < first + max; i++) { 1030 si = space_at(i); 1031 size_t size = si->_used; 1032 if (size > 0) { 1033 HeapWord* start = (HeapWord*)start_address_as_decoded_from_archive(si); 1034 regions[region_num] = MemRegion(start, size / HeapWordSize); 1035 region_num ++; 1036 log_info(cds)("Trying to map heap data: region[%d] at " INTPTR_FORMAT ", size = " SIZE_FORMAT_W(8) " bytes", 1037 i, p2i(start), size); 1038 } 1039 } 1040 1041 if (region_num == 0) { 1042 return false; // no archived java heap data 1043 } 1044 1045 // Check that ranges are within the java heap 1046 if (!G1CollectedHeap::heap()->check_archive_addresses(regions, region_num)) { 1047 log_info(cds)("UseSharedSpaces: Unable to allocate region, range is not within java heap."); 1048 return false; 1049 } 1050 1051 // allocate from java heap 1052 if (!G1CollectedHeap::heap()->alloc_archive_regions( 1053 regions, region_num, is_open_archive)) { 1054 log_info(cds)("UseSharedSpaces: Unable to allocate region, java heap range is already in use."); 1055 return false; 1056 } 1057 1058 // Map the archived heap data. No need to call MemTracker::record_virtual_memory_type() 1059 // for mapped regions as they are part of the reserved java heap, which is 1060 // already recorded. 1061 for (int i = 0; i < region_num; i++) { 1062 si = space_at(first + i); 1063 char* addr = (char*)regions[i].start(); 1064 char* base = os::map_memory(_fd, _full_path, si->_file_offset, 1065 addr, regions[i].byte_size(), si->_read_only, 1066 si->_allow_exec); 1067 if (base == NULL || base != addr) { 1068 // dealloc the regions from java heap 1069 dealloc_archive_heap_regions(regions, region_num); 1070 log_info(cds)("UseSharedSpaces: Unable to map at required address in java heap. " 1071 INTPTR_FORMAT ", size = " SIZE_FORMAT " bytes", 1072 p2i(addr), regions[i].byte_size()); 1073 return false; 1074 } 1075 } 1076 1077 if (!verify_mapped_heap_regions(first, region_num)) { 1078 // dealloc the regions from java heap 1079 dealloc_archive_heap_regions(regions, region_num); 1080 log_info(cds)("UseSharedSpaces: mapped heap regions are corrupt"); 1081 return false; 1082 } 1083 1084 // the shared heap data is mapped successfully 1085 *heap_mem = regions; 1086 *num = region_num; 1087 return true; 1088 } 1089 1090 bool FileMapInfo::verify_mapped_heap_regions(int first, int num) { 1091 assert(num > 0, "sanity"); 1092 for (int i = first; i < first + num; i++) { 1093 if (!verify_region_checksum(i)) { 1094 return false; 1095 } 1096 } 1097 return true; 1098 } 1099 1100 void FileMapInfo::patch_archived_heap_embedded_pointers() { 1101 if (!_heap_pointers_need_patching) { 1102 return; 1103 } 1104 1105 patch_archived_heap_embedded_pointers(string_ranges, 1106 num_string_ranges, 1107 MetaspaceShared::first_string); 1108 1109 patch_archived_heap_embedded_pointers(open_archive_heap_ranges, 1110 num_open_archive_heap_ranges, 1111 MetaspaceShared::first_open_archive_heap_region); 1112 } 1113 1114 void FileMapInfo::patch_archived_heap_embedded_pointers(MemRegion* ranges, int num_ranges, 1115 int first_region_idx) { 1116 for (int i=0; i<num_ranges; i++) { 1117 CDSFileMapRegion* si = space_at(i + first_region_idx); 1118 HeapShared::patch_archived_heap_embedded_pointers(ranges[i], (address)si->_oopmap, 1119 si->_oopmap_size_in_bits); 1120 } 1121 } 1122 1123 // This internally allocates objects using SystemDictionary::Object_klass(), so it 1124 // must be called after the well-known classes are resolved. 1125 void FileMapInfo::fixup_mapped_heap_regions() { 1126 // If any string regions were found, call the fill routine to make them parseable. 1127 // Note that string_ranges may be non-NULL even if no ranges were found. 1128 if (num_string_ranges != 0) { 1129 assert(string_ranges != NULL, "Null string_ranges array with non-zero count"); 1130 G1CollectedHeap::heap()->fill_archive_regions(string_ranges, num_string_ranges); 1131 } 1132 1133 // do the same for mapped open archive heap regions 1134 if (num_open_archive_heap_ranges != 0) { 1135 assert(open_archive_heap_ranges != NULL, "NULL open_archive_heap_ranges array with non-zero count"); 1136 G1CollectedHeap::heap()->fill_archive_regions(open_archive_heap_ranges, 1137 num_open_archive_heap_ranges); 1138 } 1139 } 1140 1141 // dealloc the archive regions from java heap 1142 void FileMapInfo::dealloc_archive_heap_regions(MemRegion* regions, int num) { 1143 if (num > 0) { 1144 assert(regions != NULL, "Null archive ranges array with non-zero count"); 1145 G1CollectedHeap::heap()->dealloc_archive_regions(regions, num); 1146 } 1147 } 1148 #endif // INCLUDE_CDS_JAVA_HEAP 1149 1150 bool FileMapInfo::verify_region_checksum(int i) { 1151 if (!VerifySharedSpaces) { 1152 return true; 1153 } 1154 1155 size_t sz = space_at(i)->_used; 1156 1157 if (sz == 0) { 1158 return true; // no data 1159 } 1160 if ((MetaspaceShared::is_string_region(i) && 1161 !StringTable::shared_string_mapped()) || 1162 (MetaspaceShared::is_open_archive_heap_region(i) && 1163 !HeapShared::open_archive_heap_region_mapped())) { 1164 return true; // archived heap data is not mapped 1165 } 1166 const char* buf = region_addr(i); 1167 int crc = ClassLoader::crc32(0, buf, (jint)sz); 1168 if (crc != space_at(i)->_crc) { 1169 fail_continue("Checksum verification failed."); 1170 return false; 1171 } 1172 return true; 1173 } 1174 1175 // Unmap a memory region in the address space. 1176 1177 void FileMapInfo::unmap_region(int i) { 1178 assert(!MetaspaceShared::is_heap_region(i), "sanity"); 1179 CDSFileMapRegion* si = space_at(i); 1180 size_t used = si->_used; 1181 size_t size = align_up(used, os::vm_allocation_granularity()); 1182 1183 if (used == 0) { 1184 return; 1185 } 1186 1187 char* addr = region_addr(i); 1188 if (!os::unmap_memory(addr, size)) { 1189 fail_stop("Unable to unmap shared space."); 1190 } 1191 } 1192 1193 void FileMapInfo::assert_mark(bool check) { 1194 if (!check) { 1195 fail_stop("Mark mismatch while restoring from shared file."); 1196 } 1197 } 1198 1199 void FileMapInfo::metaspace_pointers_do(MetaspaceClosure* it) { 1200 it->push(&_shared_path_table); 1201 for (int i=0; i<_shared_path_table_size; i++) { 1202 shared_path(i)->metaspace_pointers_do(it); 1203 } 1204 } 1205 1206 1207 FileMapInfo* FileMapInfo::_current_info = NULL; 1208 bool FileMapInfo::_heap_pointers_need_patching = false; 1209 Array<u8>* FileMapInfo::_shared_path_table = NULL; 1210 int FileMapInfo::_shared_path_table_size = 0; 1211 size_t FileMapInfo::_shared_path_entry_size = 0x1234baad; 1212 bool FileMapInfo::_validating_shared_path_table = false; 1213 1214 // Open the shared archive file, read and validate the header 1215 // information (version, boot classpath, etc.). If initialization 1216 // fails, shared spaces are disabled and the file is closed. [See 1217 // fail_continue.] 1218 // 1219 // Validation of the archive is done in two steps: 1220 // 1221 // [1] validate_header() - done here. This checks the header, including _paths_misc_info. 1222 // [2] validate_shared_path_table - this is done later, because the table is in the RW 1223 // region of the archive, which is not mapped yet. 1224 bool FileMapInfo::initialize() { 1225 assert(UseSharedSpaces, "UseSharedSpaces expected."); 1226 1227 if (!open_for_read()) { 1228 return false; 1229 } 1230 1231 init_from_file(_fd); 1232 if (!validate_header()) { 1233 return false; 1234 } 1235 return true; 1236 } 1237 1238 char* FileMapInfo::region_addr(int idx) { 1239 CDSFileMapRegion* si = space_at(idx); 1240 if (MetaspaceShared::is_heap_region(idx)) { 1241 assert(DumpSharedSpaces, "The following doesn't work at runtime"); 1242 return si->_used > 0 ? 1243 (char*)start_address_as_decoded_with_current_oop_encoding_mode(si) : NULL; 1244 } else { 1245 return si->_addr._base; 1246 } 1247 } 1248 1249 int FileMapHeader::compute_crc() { 1250 char* start = (char*)this; 1251 // start computing from the field after _crc 1252 char* buf = (char*)&_crc + sizeof(_crc); 1253 size_t sz = sizeof(FileMapHeader) - (buf - start); 1254 int crc = ClassLoader::crc32(0, buf, (jint)sz); 1255 return crc; 1256 } 1257 1258 // This function should only be called during run time with UseSharedSpaces enabled. 1259 bool FileMapHeader::validate() { 1260 if (VerifySharedSpaces && compute_crc() != _crc) { 1261 FileMapInfo::fail_continue("Header checksum verification failed."); 1262 return false; 1263 } 1264 1265 if (!Arguments::has_jimage()) { 1266 FileMapInfo::fail_continue("The shared archive file cannot be used with an exploded module build."); 1267 return false; 1268 } 1269 1270 if (_version != CURRENT_CDS_ARCHIVE_VERSION) { 1271 FileMapInfo::fail_continue("The shared archive file is the wrong version."); 1272 return false; 1273 } 1274 if (_magic != CDS_ARCHIVE_MAGIC) { 1275 FileMapInfo::fail_continue("The shared archive file has a bad magic number."); 1276 return false; 1277 } 1278 char header_version[JVM_IDENT_MAX]; 1279 get_header_version(header_version); 1280 if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) { 1281 log_info(class, path)("expected: %s", header_version); 1282 log_info(class, path)("actual: %s", _jvm_ident); 1283 FileMapInfo::fail_continue("The shared archive file was created by a different" 1284 " version or build of HotSpot"); 1285 return false; 1286 } 1287 if (_obj_alignment != ObjectAlignmentInBytes) { 1288 FileMapInfo::fail_continue("The shared archive file's ObjectAlignmentInBytes of %d" 1289 " does not equal the current ObjectAlignmentInBytes of " INTX_FORMAT ".", 1290 _obj_alignment, ObjectAlignmentInBytes); 1291 return false; 1292 } 1293 if (_compact_strings != CompactStrings) { 1294 FileMapInfo::fail_continue("The shared archive file's CompactStrings setting (%s)" 1295 " does not equal the current CompactStrings setting (%s).", 1296 _compact_strings ? "enabled" : "disabled", 1297 CompactStrings ? "enabled" : "disabled"); 1298 return false; 1299 } 1300 1301 // This must be done after header validation because it might change the 1302 // header data 1303 const char* prop = Arguments::get_property("java.system.class.loader"); 1304 if (prop != NULL) { 1305 warning("Archived non-system classes are disabled because the " 1306 "java.system.class.loader property is specified (value = \"%s\"). " 1307 "To use archived non-system classes, this property must be not be set", prop); 1308 _has_platform_or_app_classes = false; 1309 } 1310 1311 // For backwards compatibility, we don't check the verification setting 1312 // if the archive only contains system classes. 1313 if (_has_platform_or_app_classes && 1314 ((!_verify_local && BytecodeVerificationLocal) || 1315 (!_verify_remote && BytecodeVerificationRemote))) { 1316 FileMapInfo::fail_continue("The shared archive file was created with less restrictive " 1317 "verification setting than the current setting."); 1318 return false; 1319 } 1320 1321 return true; 1322 } 1323 1324 bool FileMapInfo::validate_header() { 1325 bool status = _header->validate(); 1326 1327 if (status) { 1328 if (!ClassLoader::check_shared_paths_misc_info(_paths_misc_info, _header->_paths_misc_info_size)) { 1329 if (!PrintSharedArchiveAndExit) { 1330 fail_continue("shared class paths mismatch (hint: enable -Xlog:class+path=info to diagnose the failure)"); 1331 status = false; 1332 } 1333 } 1334 } 1335 1336 if (_paths_misc_info != NULL) { 1337 FREE_C_HEAP_ARRAY(char, _paths_misc_info); 1338 _paths_misc_info = NULL; 1339 } 1340 return status; 1341 } 1342 1343 // Check if a given address is within one of the shared regions 1344 bool FileMapInfo::is_in_shared_region(const void* p, int idx) { 1345 assert(idx == MetaspaceShared::ro || 1346 idx == MetaspaceShared::rw || 1347 idx == MetaspaceShared::mc || 1348 idx == MetaspaceShared::md, "invalid region index"); 1349 char* base = region_addr(idx); 1350 if (p >= base && p < base + space_at(idx)->_used) { 1351 return true; 1352 } 1353 return false; 1354 } 1355 1356 // Unmap mapped regions of shared space. 1357 void FileMapInfo::stop_sharing_and_unmap(const char* msg) { 1358 FileMapInfo *map_info = FileMapInfo::current_info(); 1359 if (map_info) { 1360 map_info->fail_continue("%s", msg); 1361 for (int i = 0; i < MetaspaceShared::num_non_heap_spaces; i++) { 1362 if (!MetaspaceShared::is_heap_region(i)) { 1363 char *addr = map_info->region_addr(i); 1364 if (addr != NULL) { 1365 map_info->unmap_region(i); 1366 map_info->space_at(i)->_addr._base = NULL; 1367 } 1368 } 1369 } 1370 // Dealloc the archive heap regions only without unmapping. The regions are part 1371 // of the java heap. Unmapping of the heap regions are managed by GC. 1372 map_info->dealloc_archive_heap_regions(open_archive_heap_ranges, 1373 num_open_archive_heap_ranges); 1374 map_info->dealloc_archive_heap_regions(string_ranges, num_string_ranges); 1375 } else if (DumpSharedSpaces) { 1376 fail_stop("%s", msg); 1377 } 1378 }