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/symbolTable.hpp" 30 #include "classfile/systemDictionaryShared.hpp" 31 #include "classfile/altHashing.hpp" 32 #include "logging/log.hpp" 33 #include "logging/logStream.hpp" 34 #include "logging/logMessage.hpp" 35 #include "memory/filemap.hpp" 36 #include "memory/heapShared.inline.hpp" 37 #include "memory/iterator.inline.hpp" 38 #include "memory/metadataFactory.hpp" 39 #include "memory/metaspaceClosure.hpp" 40 #include "memory/metaspaceShared.hpp" 41 #include "memory/oopFactory.hpp" 42 #include "oops/compressedOops.inline.hpp" 43 #include "oops/objArrayOop.hpp" 44 #include "oops/oop.inline.hpp" 45 #include "prims/jvmtiExport.hpp" 46 #include "runtime/arguments.hpp" 47 #include "runtime/java.hpp" 48 #include "runtime/os.inline.hpp" 49 #include "runtime/vm_version.hpp" 50 #include "services/memTracker.hpp" 51 #include "utilities/align.hpp" 52 #include "utilities/defaultStream.hpp" 53 #if INCLUDE_G1GC 54 #include "gc/g1/g1CollectedHeap.hpp" 55 #include "gc/g1/heapRegion.hpp" 56 #endif 57 58 # include <sys/stat.h> 59 # include <errno.h> 60 61 #ifndef O_BINARY // if defined (Win32) use binary files. 62 #define O_BINARY 0 // otherwise do nothing. 63 #endif 64 65 extern address JVM_FunctionAtStart(); 66 extern address JVM_FunctionAtEnd(); 67 68 // Complain and stop. All error conditions occurring during the writing of 69 // an archive file should stop the process. Unrecoverable errors during 70 // the reading of the archive file should stop the process. 71 72 static void fail(const char *msg, va_list ap) { 73 // This occurs very early during initialization: tty is not initialized. 74 jio_fprintf(defaultStream::error_stream(), 75 "An error has occurred while processing the" 76 " shared archive file.\n"); 77 jio_vfprintf(defaultStream::error_stream(), msg, ap); 78 jio_fprintf(defaultStream::error_stream(), "\n"); 79 // Do not change the text of the below message because some tests check for it. 80 vm_exit_during_initialization("Unable to use shared archive.", NULL); 81 } 82 83 84 void FileMapInfo::fail_stop(const char *msg, ...) { 85 va_list ap; 86 va_start(ap, msg); 87 fail(msg, ap); // Never returns. 88 va_end(ap); // for completeness. 89 } 90 91 92 // Complain and continue. Recoverable errors during the reading of the 93 // archive file may continue (with sharing disabled). 94 // 95 // If we continue, then disable shared spaces and close the file. 96 97 void FileMapInfo::fail_continue(const char *msg, ...) { 98 va_list ap; 99 va_start(ap, msg); 100 MetaspaceShared::set_archive_loading_failed(); 101 if (PrintSharedArchiveAndExit && _validating_shared_path_table) { 102 // If we are doing PrintSharedArchiveAndExit and some of the classpath entries 103 // do not validate, we can still continue "limping" to validate the remaining 104 // entries. No need to quit. 105 tty->print("["); 106 tty->vprint(msg, ap); 107 tty->print_cr("]"); 108 } else { 109 if (RequireSharedSpaces) { 110 fail(msg, ap); 111 } else { 112 if (log_is_enabled(Info, cds)) { 113 ResourceMark rm; 114 LogStream ls(Log(cds)::info()); 115 ls.print("UseSharedSpaces: "); 116 ls.vprint_cr(msg, ap); 117 } 118 } 119 UseSharedSpaces = false; 120 assert(current_info() != NULL, "singleton must be registered"); 121 current_info()->close(); 122 } 123 va_end(ap); 124 } 125 126 // Fill in the fileMapInfo structure with data about this VM instance. 127 128 // This method copies the vm version info into header_version. If the version is too 129 // long then a truncated version, which has a hash code appended to it, is copied. 130 // 131 // Using a template enables this method to verify that header_version is an array of 132 // length JVM_IDENT_MAX. This ensures that the code that writes to the CDS file and 133 // the code that reads the CDS file will both use the same size buffer. Hence, will 134 // use identical truncation. This is necessary for matching of truncated versions. 135 template <int N> static void get_header_version(char (&header_version) [N]) { 136 assert(N == JVM_IDENT_MAX, "Bad header_version size"); 137 138 const char *vm_version = VM_Version::internal_vm_info_string(); 139 const int version_len = (int)strlen(vm_version); 140 141 if (version_len < (JVM_IDENT_MAX-1)) { 142 strcpy(header_version, vm_version); 143 144 } else { 145 // Get the hash value. Use a static seed because the hash needs to return the same 146 // value over multiple jvm invocations. 147 unsigned int hash = AltHashing::murmur3_32(8191, (const jbyte*)vm_version, version_len); 148 149 // Truncate the ident, saving room for the 8 hex character hash value. 150 strncpy(header_version, vm_version, JVM_IDENT_MAX-9); 151 152 // Append the hash code as eight hex digits. 153 sprintf(&header_version[JVM_IDENT_MAX-9], "%08x", hash); 154 header_version[JVM_IDENT_MAX-1] = 0; // Null terminate. 155 } 156 } 157 158 FileMapInfo::FileMapInfo() { 159 assert(_current_info == NULL, "must be singleton"); // not thread safe 160 _current_info = this; 161 memset((void*)this, 0, sizeof(FileMapInfo)); 162 _file_offset = 0; 163 _file_open = false; 164 _header = (FileMapHeader*)os::malloc(sizeof(FileMapHeader), mtInternal); 165 _header->_version = INVALID_CDS_ARCHIVE_VERSION; 166 _header->_has_platform_or_app_classes = true; 167 } 168 169 FileMapInfo::~FileMapInfo() { 170 assert(_current_info == this, "must be singleton"); // not thread safe 171 _current_info = NULL; 172 } 173 174 void FileMapInfo::populate_header(size_t alignment) { 175 _header->populate(this, alignment); 176 } 177 178 void FileMapHeader::populate(FileMapInfo* mapinfo, size_t alignment) { 179 _magic = CDS_ARCHIVE_MAGIC; 180 _version = CURRENT_CDS_ARCHIVE_VERSION; 181 _alignment = alignment; 182 _obj_alignment = ObjectAlignmentInBytes; 183 _compact_strings = CompactStrings; 184 _narrow_oop_mode = Universe::narrow_oop_mode(); 185 _narrow_oop_base = Universe::narrow_oop_base(); 186 _narrow_oop_shift = Universe::narrow_oop_shift(); 187 _max_heap_size = MaxHeapSize; 188 _narrow_klass_base = Universe::narrow_klass_base(); 189 _narrow_klass_shift = Universe::narrow_klass_shift(); 190 _shared_path_table_size = mapinfo->_shared_path_table_size; 191 _shared_path_table = mapinfo->_shared_path_table; 192 _shared_path_entry_size = mapinfo->_shared_path_entry_size; 193 if (HeapShared::is_heap_object_archiving_allowed()) { 194 _heap_reserved = Universe::heap()->reserved_region(); 195 } 196 197 // The following fields are for sanity checks for whether this archive 198 // will function correctly with this JVM and the bootclasspath it's 199 // invoked with. 200 201 // JVM version string ... changes on each build. 202 get_header_version(_jvm_ident); 203 204 ClassLoaderExt::finalize_shared_paths_misc_info(); 205 _app_class_paths_start_index = ClassLoaderExt::app_class_paths_start_index(); 206 _app_module_paths_start_index = ClassLoaderExt::app_module_paths_start_index(); 207 _max_used_path_index = ClassLoaderExt::max_used_path_index(); 208 209 _verify_local = BytecodeVerificationLocal; 210 _verify_remote = BytecodeVerificationRemote; 211 _has_platform_or_app_classes = ClassLoaderExt::has_platform_or_app_classes(); 212 _shared_base_address = SharedBaseAddress; 213 _allow_archiving_with_java_agent = AllowArchivingWithJavaAgent; 214 } 215 216 void SharedClassPathEntry::init(const char* name, bool is_modules_image, TRAPS) { 217 assert(DumpSharedSpaces, "dump time only"); 218 _timestamp = 0; 219 _filesize = 0; 220 221 struct stat st; 222 if (os::stat(name, &st) == 0) { 223 if ((st.st_mode & S_IFMT) == S_IFDIR) { 224 _type = dir_entry; 225 } else { 226 // The timestamp of the modules_image is not checked at runtime. 227 if (is_modules_image) { 228 _type = modules_image_entry; 229 } else { 230 _type = jar_entry; 231 _timestamp = st.st_mtime; 232 } 233 _filesize = st.st_size; 234 } 235 } else { 236 // The file/dir must exist, or it would not have been added 237 // into ClassLoader::classpath_entry(). 238 // 239 // If we can't access a jar file in the boot path, then we can't 240 // make assumptions about where classes get loaded from. 241 FileMapInfo::fail_stop("Unable to open file %s.", name); 242 } 243 244 size_t len = strlen(name) + 1; 245 _name = MetadataFactory::new_array<char>(ClassLoaderData::the_null_class_loader_data(), (int)len, THREAD); 246 strcpy(_name->data(), name); 247 } 248 249 bool SharedClassPathEntry::validate(bool is_class_path) { 250 assert(UseSharedSpaces, "runtime only"); 251 252 struct stat st; 253 const char* name; 254 255 // In order to validate the runtime modules image file size against the archived 256 // size information, we need to obtain the runtime modules image path. The recorded 257 // dump time modules image path in the archive may be different from the runtime path 258 // if the JDK image has beed moved after generating the archive. 259 if (is_modules_image()) { 260 name = ClassLoader::get_jrt_entry()->name(); 261 } else { 262 name = this->name(); 263 } 264 265 bool ok = true; 266 log_info(class, path)("checking shared classpath entry: %s", name); 267 if (os::stat(name, &st) != 0 && is_class_path) { 268 // If the archived module path entry does not exist at runtime, it is not fatal 269 // (no need to invalid the shared archive) because the shared runtime visibility check 270 // filters out any archived module classes that do not have a matching runtime 271 // module path location. 272 FileMapInfo::fail_continue("Required classpath entry does not exist: %s", name); 273 ok = false; 274 } else if (is_dir()) { 275 if (!os::dir_is_empty(name)) { 276 FileMapInfo::fail_continue("directory is not empty: %s", name); 277 ok = false; 278 } 279 } else if ((has_timestamp() && _timestamp != st.st_mtime) || 280 _filesize != st.st_size) { 281 ok = false; 282 if (PrintSharedArchiveAndExit) { 283 FileMapInfo::fail_continue(_timestamp != st.st_mtime ? 284 "Timestamp mismatch" : 285 "File size mismatch"); 286 } else { 287 FileMapInfo::fail_continue("A jar file is not the one used while building" 288 " the shared archive file: %s", name); 289 } 290 } 291 292 if (PrintSharedArchiveAndExit && !ok) { 293 // If PrintSharedArchiveAndExit is enabled, don't report failure to the 294 // caller. Please see above comments for more details. 295 ok = true; 296 } 297 return ok; 298 } 299 300 void SharedClassPathEntry::metaspace_pointers_do(MetaspaceClosure* it) { 301 it->push(&_name); 302 it->push(&_manifest); 303 } 304 305 void FileMapInfo::allocate_shared_path_table() { 306 assert(DumpSharedSpaces, "Sanity"); 307 308 Thread* THREAD = Thread::current(); 309 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data(); 310 ClassPathEntry* jrt = ClassLoader::get_jrt_entry(); 311 312 assert(jrt != NULL, 313 "No modular java runtime image present when allocating the CDS classpath entry table"); 314 315 size_t entry_size = sizeof(SharedClassPathEntry); // assert ( should be 8 byte aligned??) 316 int num_boot_classpath_entries = ClassLoader::num_boot_classpath_entries(); 317 int num_app_classpath_entries = ClassLoader::num_app_classpath_entries(); 318 int num_module_path_entries = ClassLoader::num_module_path_entries(); 319 int num_entries = num_boot_classpath_entries + num_app_classpath_entries + num_module_path_entries; 320 size_t bytes = entry_size * num_entries; 321 322 _shared_path_table = MetadataFactory::new_array<u8>(loader_data, (int)(bytes + 7 / 8), THREAD); 323 _shared_path_table_size = num_entries; 324 _shared_path_entry_size = entry_size; 325 326 // 1. boot class path 327 int i = 0; 328 ClassPathEntry* cpe = jrt; 329 while (cpe != NULL) { 330 bool is_jrt = (cpe == jrt); 331 const char* type = (is_jrt ? "jrt" : (cpe->is_jar_file() ? "jar" : "dir")); 332 log_info(class, path)("add main shared path (%s) %s", type, cpe->name()); 333 SharedClassPathEntry* ent = shared_path(i); 334 ent->init(cpe->name(), is_jrt, THREAD); 335 if (!is_jrt) { // No need to do the modules image. 336 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error. 337 update_shared_classpath(cpe, ent, THREAD); 338 } 339 cpe = ClassLoader::get_next_boot_classpath_entry(cpe); 340 i++; 341 } 342 assert(i == num_boot_classpath_entries, 343 "number of boot class path entry mismatch"); 344 345 // 2. app class path 346 ClassPathEntry *acpe = ClassLoader::app_classpath_entries(); 347 while (acpe != NULL) { 348 log_info(class, path)("add app shared path %s", acpe->name()); 349 SharedClassPathEntry* ent = shared_path(i); 350 ent->init(acpe->name(), false, THREAD); 351 EXCEPTION_MARK; 352 update_shared_classpath(acpe, ent, THREAD); 353 acpe = acpe->next(); 354 i++; 355 } 356 357 // 3. module path 358 ClassPathEntry *mpe = ClassLoader::module_path_entries(); 359 while (mpe != NULL) { 360 log_info(class, path)("add module path %s",mpe->name()); 361 SharedClassPathEntry* ent = shared_path(i); 362 ent->init(mpe->name(), false, THREAD); 363 EXCEPTION_MARK; 364 update_shared_classpath(mpe, ent, THREAD); 365 mpe = mpe->next(); 366 i++; 367 } 368 assert(i == num_entries, "number of shared path entry mismatch"); 369 } 370 371 void FileMapInfo::check_nonempty_dir_in_shared_path_table() { 372 assert(DumpSharedSpaces, "dump time only"); 373 374 bool has_nonempty_dir = false; 375 376 int last = _shared_path_table_size - 1; 377 if (last > ClassLoaderExt::max_used_path_index()) { 378 // no need to check any path beyond max_used_path_index 379 last = ClassLoaderExt::max_used_path_index(); 380 } 381 382 for (int i = 0; i <= last; i++) { 383 SharedClassPathEntry *e = shared_path(i); 384 if (e->is_dir()) { 385 const char* path = e->name(); 386 if (!os::dir_is_empty(path)) { 387 tty->print_cr("Error: non-empty directory '%s'", path); 388 has_nonempty_dir = true; 389 } 390 } 391 } 392 393 if (has_nonempty_dir) { 394 ClassLoader::exit_with_path_failure("Cannot have non-empty directory in paths", NULL); 395 } 396 } 397 398 class ManifestStream: public ResourceObj { 399 private: 400 u1* _buffer_start; // Buffer bottom 401 u1* _buffer_end; // Buffer top (one past last element) 402 u1* _current; // Current buffer position 403 404 public: 405 // Constructor 406 ManifestStream(u1* buffer, int length) : _buffer_start(buffer), 407 _current(buffer) { 408 _buffer_end = buffer + length; 409 } 410 411 static bool is_attr(u1* attr, const char* name) { 412 return strncmp((const char*)attr, name, strlen(name)) == 0; 413 } 414 415 static char* copy_attr(u1* value, size_t len) { 416 char* buf = NEW_RESOURCE_ARRAY(char, len + 1); 417 strncpy(buf, (char*)value, len); 418 buf[len] = 0; 419 return buf; 420 } 421 422 // The return value indicates if the JAR is signed or not 423 bool check_is_signed() { 424 u1* attr = _current; 425 bool isSigned = false; 426 while (_current < _buffer_end) { 427 if (*_current == '\n') { 428 *_current = '\0'; 429 u1* value = (u1*)strchr((char*)attr, ':'); 430 if (value != NULL) { 431 assert(*(value+1) == ' ', "Unrecognized format" ); 432 if (strstr((char*)attr, "-Digest") != NULL) { 433 isSigned = true; 434 break; 435 } 436 } 437 *_current = '\n'; // restore 438 attr = _current + 1; 439 } 440 _current ++; 441 } 442 return isSigned; 443 } 444 }; 445 446 void FileMapInfo::update_shared_classpath(ClassPathEntry *cpe, SharedClassPathEntry* ent, TRAPS) { 447 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data(); 448 ResourceMark rm(THREAD); 449 jint manifest_size; 450 451 if (cpe->is_jar_file()) { 452 assert(ent->is_jar(), "the shared class path entry is not a JAR file"); 453 char* manifest = ClassLoaderExt::read_manifest(cpe, &manifest_size, CHECK); 454 if (manifest != NULL) { 455 ManifestStream* stream = new ManifestStream((u1*)manifest, 456 manifest_size); 457 if (stream->check_is_signed()) { 458 ent->set_is_signed(); 459 } else { 460 // Copy the manifest into the shared archive 461 manifest = ClassLoaderExt::read_raw_manifest(cpe, &manifest_size, CHECK); 462 Array<u1>* buf = MetadataFactory::new_array<u1>(loader_data, 463 manifest_size, 464 THREAD); 465 char* p = (char*)(buf->data()); 466 memcpy(p, manifest, manifest_size); 467 ent->set_manifest(buf); 468 } 469 } 470 } 471 } 472 473 474 bool FileMapInfo::validate_shared_path_table() { 475 assert(UseSharedSpaces, "runtime only"); 476 477 _validating_shared_path_table = true; 478 _shared_path_table = _header->_shared_path_table; 479 _shared_path_entry_size = _header->_shared_path_entry_size; 480 _shared_path_table_size = _header->_shared_path_table_size; 481 482 int module_paths_start_index = _header->_app_module_paths_start_index; 483 484 // validate the path entries up to the _max_used_path_index 485 for (int i=0; i < _header->_max_used_path_index + 1; i++) { 486 if (i < module_paths_start_index) { 487 if (shared_path(i)->validate()) { 488 log_info(class, path)("ok"); 489 } else { 490 assert(!UseSharedSpaces, "UseSharedSpaces should be disabled"); 491 return false; 492 } 493 } else if (i >= module_paths_start_index) { 494 if (shared_path(i)->validate(false /* not a class path entry */)) { 495 log_info(class, path)("ok"); 496 } else { 497 assert(!UseSharedSpaces, "UseSharedSpaces should be disabled"); 498 return false; 499 } 500 } 501 } 502 503 _validating_shared_path_table = false; 504 return true; 505 } 506 507 // Read the FileMapInfo information from the file. 508 509 bool FileMapInfo::init_from_file(int fd) { 510 size_t sz = sizeof(FileMapHeader); 511 size_t n = os::read(fd, _header, (unsigned int)sz); 512 if (n != sz) { 513 fail_continue("Unable to read the file header."); 514 return false; 515 } 516 if (_header->_version != CURRENT_CDS_ARCHIVE_VERSION) { 517 fail_continue("The shared archive file has the wrong version."); 518 return false; 519 } 520 _file_offset = (long)n; 521 522 size_t info_size = _header->_paths_misc_info_size; 523 _paths_misc_info = NEW_C_HEAP_ARRAY_RETURN_NULL(char, info_size, mtClass); 524 if (_paths_misc_info == NULL) { 525 fail_continue("Unable to read the file header."); 526 return false; 527 } 528 n = os::read(fd, _paths_misc_info, (unsigned int)info_size); 529 if (n != info_size) { 530 fail_continue("Unable to read the shared path info header."); 531 FREE_C_HEAP_ARRAY(char, _paths_misc_info); 532 _paths_misc_info = NULL; 533 return false; 534 } 535 536 size_t len = lseek(fd, 0, SEEK_END); 537 CDSFileMapRegion* si = space_at(MetaspaceShared::last_valid_region); 538 // The last space might be empty 539 if (si->_file_offset > len || len - si->_file_offset < si->_used) { 540 fail_continue("The shared archive file has been truncated."); 541 return false; 542 } 543 544 _file_offset += (long)n; 545 SharedBaseAddress = _header->_shared_base_address; 546 return true; 547 } 548 549 550 // Read the FileMapInfo information from the file. 551 bool FileMapInfo::open_for_read() { 552 _full_path = Arguments::GetSharedArchivePath(); 553 int fd = open(_full_path, O_RDONLY | O_BINARY, 0); 554 if (fd < 0) { 555 if (errno == ENOENT) { 556 // Not locating the shared archive is ok. 557 fail_continue("Specified shared archive not found."); 558 } else { 559 fail_continue("Failed to open shared archive file (%s).", 560 os::strerror(errno)); 561 } 562 return false; 563 } 564 565 _fd = fd; 566 _file_open = true; 567 return true; 568 } 569 570 571 // Write the FileMapInfo information to the file. 572 573 void FileMapInfo::open_for_write() { 574 _full_path = Arguments::GetSharedArchivePath(); 575 LogMessage(cds) msg; 576 if (msg.is_info()) { 577 msg.info("Dumping shared data to file: "); 578 msg.info(" %s", _full_path); 579 } 580 581 #ifdef _WINDOWS // On Windows, need WRITE permission to remove the file. 582 chmod(_full_path, _S_IREAD | _S_IWRITE); 583 #endif 584 585 // Use remove() to delete the existing file because, on Unix, this will 586 // allow processes that have it open continued access to the file. 587 remove(_full_path); 588 int fd = open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444); 589 if (fd < 0) { 590 fail_stop("Unable to create shared archive file %s: (%s).", _full_path, 591 os::strerror(errno)); 592 } 593 _fd = fd; 594 _file_offset = 0; 595 _file_open = true; 596 } 597 598 599 // Write the header to the file, seek to the next allocation boundary. 600 601 void FileMapInfo::write_header() { 602 int info_size = ClassLoader::get_shared_paths_misc_info_size(); 603 604 _header->_paths_misc_info_size = info_size; 605 606 align_file_position(); 607 write_bytes(_header, sizeof(FileMapHeader)); 608 write_bytes(ClassLoader::get_shared_paths_misc_info(), (size_t)info_size); 609 align_file_position(); 610 } 611 612 613 // Dump region to file. 614 615 void FileMapInfo::write_region(int region, char* base, size_t size, 616 bool read_only, bool allow_exec) { 617 CDSFileMapRegion* si = space_at(region); 618 619 if (_file_open) { 620 guarantee(si->_file_offset == _file_offset, "file offset mismatch."); 621 log_info(cds)("Shared file region %d: " SIZE_FORMAT_HEX_W(08) 622 " bytes, addr " INTPTR_FORMAT " file offset " SIZE_FORMAT_HEX_W(08), 623 region, size, p2i(base), _file_offset); 624 } else { 625 si->_file_offset = _file_offset; 626 } 627 if (HeapShared::is_heap_region(region)) { 628 assert((base - (char*)Universe::narrow_oop_base()) % HeapWordSize == 0, "Sanity"); 629 if (base != NULL) { 630 si->_addr._offset = (intx)CompressedOops::encode_not_null((oop)base); 631 } else { 632 si->_addr._offset = 0; 633 } 634 } else { 635 si->_addr._base = base; 636 } 637 si->_used = size; 638 si->_read_only = read_only; 639 si->_allow_exec = allow_exec; 640 si->_crc = ClassLoader::crc32(0, base, (jint)size); 641 if (base != NULL) { 642 write_bytes_aligned(base, size); 643 } 644 } 645 646 // Write out the given archive heap memory regions. GC code combines multiple 647 // consecutive archive GC regions into one MemRegion whenever possible and 648 // produces the 'heap_mem' array. 649 // 650 // If the archive heap memory size is smaller than a single dump time GC region 651 // size, there is only one MemRegion in the array. 652 // 653 // If the archive heap memory size is bigger than one dump time GC region size, 654 // the 'heap_mem' array may contain more than one consolidated MemRegions. When 655 // the first/bottom archive GC region is a partial GC region (with the empty 656 // portion at the higher address within the region), one MemRegion is used for 657 // the bottom partial archive GC region. The rest of the consecutive archive 658 // GC regions are combined into another MemRegion. 659 // 660 // Here's the mapping from (archive heap GC regions) -> (GrowableArray<MemRegion> *regions). 661 // + We have 1 or more archive heap regions: ah0, ah1, ah2 ..... ahn 662 // + We have 1 or 2 consolidated heap memory regions: r0 and r1 663 // 664 // If there's a single archive GC region (ah0), then r0 == ah0, and r1 is empty. 665 // Otherwise: 666 // 667 // "X" represented space that's occupied by heap objects. 668 // "_" represented unused spaced in the heap region. 669 // 670 // 671 // |ah0 | ah1 | ah2| ...... | ahn| 672 // |XXXXXX|__ |XXXXX|XXXX|XXXXXXXX|XXXX| 673 // |<-r0->| |<- r1 ----------------->| 674 // ^^^ 675 // | 676 // +-- gap 677 size_t FileMapInfo::write_archive_heap_regions(GrowableArray<MemRegion> *heap_mem, 678 GrowableArray<ArchiveHeapOopmapInfo> *oopmaps, 679 int first_region_id, int max_num_regions, 680 bool print_log) { 681 assert(max_num_regions <= 2, "Only support maximum 2 memory regions"); 682 683 int arr_len = heap_mem == NULL ? 0 : heap_mem->length(); 684 if(arr_len > max_num_regions) { 685 fail_stop("Unable to write archive heap memory regions: " 686 "number of memory regions exceeds maximum due to fragmentation"); 687 } 688 689 size_t total_size = 0; 690 for (int i = first_region_id, arr_idx = 0; 691 i < first_region_id + max_num_regions; 692 i++, arr_idx++) { 693 char* start = NULL; 694 size_t size = 0; 695 if (arr_idx < arr_len) { 696 start = (char*)heap_mem->at(arr_idx).start(); 697 size = heap_mem->at(arr_idx).byte_size(); 698 total_size += size; 699 } 700 701 if (print_log) { 702 log_info(cds)("Archive heap region %d " INTPTR_FORMAT " - " INTPTR_FORMAT " = " SIZE_FORMAT_W(8) " bytes", 703 i, p2i(start), p2i(start + size), size); 704 } 705 write_region(i, start, size, false, false); 706 if (size > 0) { 707 space_at(i)->_oopmap = oopmaps->at(arr_idx)._oopmap; 708 space_at(i)->_oopmap_size_in_bits = oopmaps->at(arr_idx)._oopmap_size_in_bits; 709 } 710 } 711 return total_size; 712 } 713 714 // Dump bytes to file -- at the current file position. 715 716 void FileMapInfo::write_bytes(const void* buffer, size_t nbytes) { 717 if (_file_open) { 718 size_t n = os::write(_fd, buffer, (unsigned int)nbytes); 719 if (n != nbytes) { 720 // It is dangerous to leave the corrupted shared archive file around, 721 // close and remove the file. See bug 6372906. 722 close(); 723 remove(_full_path); 724 fail_stop("Unable to write to shared archive file."); 725 } 726 } 727 _file_offset += nbytes; 728 } 729 730 731 // Align file position to an allocation unit boundary. 732 733 void FileMapInfo::align_file_position() { 734 size_t new_file_offset = align_up(_file_offset, 735 os::vm_allocation_granularity()); 736 if (new_file_offset != _file_offset) { 737 _file_offset = new_file_offset; 738 if (_file_open) { 739 // Seek one byte back from the target and write a byte to insure 740 // that the written file is the correct length. 741 _file_offset -= 1; 742 if (lseek(_fd, (long)_file_offset, SEEK_SET) < 0) { 743 fail_stop("Unable to seek."); 744 } 745 char zero = 0; 746 write_bytes(&zero, 1); 747 } 748 } 749 } 750 751 752 // Dump bytes to file -- at the current file position. 753 754 void FileMapInfo::write_bytes_aligned(const void* buffer, size_t nbytes) { 755 align_file_position(); 756 write_bytes(buffer, nbytes); 757 align_file_position(); 758 } 759 760 761 // Close the shared archive file. This does NOT unmap mapped regions. 762 763 void FileMapInfo::close() { 764 if (_file_open) { 765 if (::close(_fd) < 0) { 766 fail_stop("Unable to close the shared archive file."); 767 } 768 _file_open = false; 769 _fd = -1; 770 } 771 } 772 773 774 // JVM/TI RedefineClasses() support: 775 // Remap the shared readonly space to shared readwrite, private. 776 bool FileMapInfo::remap_shared_readonly_as_readwrite() { 777 int idx = MetaspaceShared::ro; 778 CDSFileMapRegion* si = space_at(idx); 779 if (!si->_read_only) { 780 // the space is already readwrite so we are done 781 return true; 782 } 783 size_t used = si->_used; 784 size_t size = align_up(used, os::vm_allocation_granularity()); 785 if (!open_for_read()) { 786 return false; 787 } 788 char *addr = region_addr(idx); 789 char *base = os::remap_memory(_fd, _full_path, si->_file_offset, 790 addr, size, false /* !read_only */, 791 si->_allow_exec); 792 close(); 793 if (base == NULL) { 794 fail_continue("Unable to remap shared readonly space (errno=%d).", errno); 795 return false; 796 } 797 if (base != addr) { 798 fail_continue("Unable to remap shared readonly space at required address."); 799 return false; 800 } 801 si->_read_only = false; 802 return true; 803 } 804 805 // Map the whole region at once, assumed to be allocated contiguously. 806 ReservedSpace FileMapInfo::reserve_shared_memory() { 807 char* requested_addr = region_addr(0); 808 size_t size = FileMapInfo::core_spaces_size(); 809 810 // Reserve the space first, then map otherwise map will go right over some 811 // other reserved memory (like the code cache). 812 ReservedSpace rs(size, os::vm_allocation_granularity(), false, requested_addr); 813 if (!rs.is_reserved()) { 814 fail_continue("Unable to reserve shared space at required address " 815 INTPTR_FORMAT, p2i(requested_addr)); 816 return rs; 817 } 818 // the reserved virtual memory is for mapping class data sharing archive 819 MemTracker::record_virtual_memory_type((address)rs.base(), mtClassShared); 820 821 return rs; 822 } 823 824 // Memory map a region in the address space. 825 static const char* shared_region_name[] = { "MiscData", "ReadWrite", "ReadOnly", "MiscCode", "OptionalData", 826 "String1", "String2", "OpenArchive1", "OpenArchive2" }; 827 828 char* FileMapInfo::map_region(int i, char** top_ret) { 829 assert(!HeapShared::is_heap_region(i), "sanity"); 830 CDSFileMapRegion* si = space_at(i); 831 size_t used = si->_used; 832 size_t alignment = os::vm_allocation_granularity(); 833 size_t size = align_up(used, alignment); 834 char *requested_addr = region_addr(i); 835 836 // If a tool agent is in use (debugging enabled), we must map the address space RW 837 if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space()) { 838 si->_read_only = false; 839 } 840 841 // map the contents of the CDS archive in this memory 842 char *base = os::map_memory(_fd, _full_path, si->_file_offset, 843 requested_addr, size, si->_read_only, 844 si->_allow_exec); 845 if (base == NULL || base != requested_addr) { 846 fail_continue("Unable to map %s shared space at required address.", shared_region_name[i]); 847 return NULL; 848 } 849 #ifdef _WINDOWS 850 // This call is Windows-only because the memory_type gets recorded for the other platforms 851 // in method FileMapInfo::reserve_shared_memory(), which is not called on Windows. 852 MemTracker::record_virtual_memory_type((address)base, mtClassShared); 853 #endif 854 855 856 if (!verify_region_checksum(i)) { 857 return NULL; 858 } 859 860 *top_ret = base + size; 861 return base; 862 } 863 864 address FileMapInfo::decode_start_address(CDSFileMapRegion* spc, bool with_current_oop_encoding_mode) { 865 if (with_current_oop_encoding_mode) { 866 return (address)CompressedOops::decode_not_null(offset_of_space(spc)); 867 } else { 868 return (address)HeapShared::decode_from_archive(offset_of_space(spc)); 869 } 870 } 871 872 static MemRegion *closed_archive_heap_ranges = NULL; 873 static MemRegion *open_archive_heap_ranges = NULL; 874 static int num_closed_archive_heap_ranges = 0; 875 static int num_open_archive_heap_ranges = 0; 876 877 #if INCLUDE_CDS_JAVA_HEAP 878 bool FileMapInfo::has_heap_regions() { 879 return (_header->_space[MetaspaceShared::first_closed_archive_heap_region]._used > 0); 880 } 881 882 // Returns the address range of the archived heap regions computed using the 883 // current oop encoding mode. This range may be different than the one seen at 884 // dump time due to encoding mode differences. The result is used in determining 885 // if/how these regions should be relocated at run time. 886 MemRegion FileMapInfo::get_heap_regions_range_with_current_oop_encoding_mode() { 887 address start = (address) max_uintx; 888 address end = NULL; 889 890 for (int i = MetaspaceShared::first_closed_archive_heap_region; 891 i <= MetaspaceShared::last_valid_region; 892 i++) { 893 CDSFileMapRegion* si = space_at(i); 894 size_t size = si->_used; 895 if (size > 0) { 896 address s = start_address_as_decoded_with_current_oop_encoding_mode(si); 897 address e = s + size; 898 if (start > s) { 899 start = s; 900 } 901 if (end < e) { 902 end = e; 903 } 904 } 905 } 906 assert(end != NULL, "must have at least one used heap region"); 907 return MemRegion((HeapWord*)start, (HeapWord*)end); 908 } 909 910 // 911 // Map the closed and open archive heap objects to the runtime java heap. 912 // 913 // The shared objects are mapped at (or close to ) the java heap top in 914 // closed archive regions. The mapped objects contain no out-going 915 // references to any other java heap regions. GC does not write into the 916 // mapped closed archive heap region. 917 // 918 // The open archive heap objects are mapped below the shared objects in 919 // the runtime java heap. The mapped open archive heap data only contains 920 // references to the shared objects and open archive objects initially. 921 // During runtime execution, out-going references to any other java heap 922 // regions may be added. GC may mark and update references in the mapped 923 // open archive objects. 924 void FileMapInfo::map_heap_regions_impl() { 925 if (!HeapShared::is_heap_object_archiving_allowed()) { 926 log_info(cds)("CDS heap data is being ignored. UseG1GC, " 927 "UseCompressedOops and UseCompressedClassPointers are required."); 928 return; 929 } 930 931 if (JvmtiExport::should_post_class_file_load_hook() && JvmtiExport::has_early_class_hook_env()) { 932 ShouldNotReachHere(); // CDS should have been disabled. 933 // The archived objects are mapped at JVM start-up, but we don't know if 934 // j.l.String or j.l.Class might be replaced by the ClassFileLoadHook, 935 // which would make the archived String or mirror objects invalid. Let's be safe and not 936 // use the archived objects. These 2 classes are loaded during the JVMTI "early" stage. 937 // 938 // If JvmtiExport::has_early_class_hook_env() is false, the classes of some objects 939 // in the archived subgraphs may be replaced by the ClassFileLoadHook. But that's OK 940 // because we won't install an archived object subgraph if the klass of any of the 941 // referenced objects are replaced. See HeapShared::initialize_from_archived_subgraph(). 942 } 943 944 MemRegion heap_reserved = Universe::heap()->reserved_region(); 945 946 log_info(cds)("CDS archive was created with max heap size = " SIZE_FORMAT "M, and the following configuration:", 947 max_heap_size()/M); 948 log_info(cds)(" narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d", 949 p2i(narrow_klass_base()), narrow_klass_shift()); 950 log_info(cds)(" narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d", 951 narrow_oop_mode(), p2i(narrow_oop_base()), narrow_oop_shift()); 952 953 log_info(cds)("The current max heap size = " SIZE_FORMAT "M, HeapRegion::GrainBytes = " SIZE_FORMAT, 954 heap_reserved.byte_size()/M, HeapRegion::GrainBytes); 955 log_info(cds)(" narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d", 956 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift()); 957 log_info(cds)(" narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d", 958 Universe::narrow_oop_mode(), p2i(Universe::narrow_oop_base()), Universe::narrow_oop_shift()); 959 960 if (narrow_klass_base() != Universe::narrow_klass_base() || 961 narrow_klass_shift() != Universe::narrow_klass_shift()) { 962 log_info(cds)("CDS heap data cannot be used because the archive was created with an incompatible narrow klass encoding mode."); 963 return; 964 } 965 966 if (narrow_oop_mode() != Universe::narrow_oop_mode() || 967 narrow_oop_base() != Universe::narrow_oop_base() || 968 narrow_oop_shift() != Universe::narrow_oop_shift()) { 969 log_info(cds)("CDS heap data need to be relocated because the archive was created with an incompatible oop encoding mode."); 970 _heap_pointers_need_patching = true; 971 } else { 972 MemRegion range = get_heap_regions_range_with_current_oop_encoding_mode(); 973 if (!heap_reserved.contains(range)) { 974 log_info(cds)("CDS heap data need to be relocated because"); 975 log_info(cds)("the desired range " PTR_FORMAT " - " PTR_FORMAT, p2i(range.start()), p2i(range.end())); 976 log_info(cds)("is outside of the heap " PTR_FORMAT " - " PTR_FORMAT, p2i(heap_reserved.start()), p2i(heap_reserved.end())); 977 _heap_pointers_need_patching = true; 978 } 979 } 980 981 ptrdiff_t delta = 0; 982 if (_heap_pointers_need_patching) { 983 // dumptime heap end ------------v 984 // [ |archived heap regions| ] runtime heap end ------v 985 // [ |archived heap regions| ] 986 // |<-----delta-------------------->| 987 // 988 // At dump time, the archived heap regions were near the top of the heap. 989 // At run time, they may not be inside the heap, so we move them so 990 // that they are now near the top of the runtime time. This can be done by 991 // the simple math of adding the delta as shown above. 992 address dumptime_heap_end = (address)_header->_heap_reserved.end(); 993 address runtime_heap_end = (address)heap_reserved.end(); 994 delta = runtime_heap_end - dumptime_heap_end; 995 } 996 997 log_info(cds)("CDS heap data relocation delta = " INTX_FORMAT " bytes", delta); 998 HeapShared::init_narrow_oop_decoding(narrow_oop_base() + delta, narrow_oop_shift()); 999 1000 CDSFileMapRegion* si = space_at(MetaspaceShared::first_closed_archive_heap_region); 1001 address relocated_closed_heap_region_bottom = start_address_as_decoded_from_archive(si); 1002 if (!is_aligned(relocated_closed_heap_region_bottom, HeapRegion::GrainBytes)) { 1003 // Align the bottom of the closed archive heap regions at G1 region boundary. 1004 // This will avoid the situation where the highest open region and the lowest 1005 // closed region sharing the same G1 region. Otherwise we will fail to map the 1006 // open regions. 1007 size_t align = size_t(relocated_closed_heap_region_bottom) % HeapRegion::GrainBytes; 1008 delta -= align; 1009 log_info(cds)("CDS heap data need to be relocated lower by a further " SIZE_FORMAT 1010 " bytes to " INTX_FORMAT " to be aligned with HeapRegion::GrainBytes", 1011 align, delta); 1012 HeapShared::init_narrow_oop_decoding(narrow_oop_base() + delta, narrow_oop_shift()); 1013 _heap_pointers_need_patching = true; 1014 relocated_closed_heap_region_bottom = start_address_as_decoded_from_archive(si); 1015 } 1016 assert(is_aligned(relocated_closed_heap_region_bottom, HeapRegion::GrainBytes), 1017 "must be"); 1018 1019 // Map the closed_archive_heap regions, GC does not write into the regions. 1020 if (map_heap_data(&closed_archive_heap_ranges, 1021 MetaspaceShared::first_closed_archive_heap_region, 1022 MetaspaceShared::max_closed_archive_heap_region, 1023 &num_closed_archive_heap_ranges)) { 1024 HeapShared::set_closed_archive_heap_region_mapped(); 1025 1026 // Now, map open_archive heap regions, GC can write into the regions. 1027 if (map_heap_data(&open_archive_heap_ranges, 1028 MetaspaceShared::first_open_archive_heap_region, 1029 MetaspaceShared::max_open_archive_heap_region, 1030 &num_open_archive_heap_ranges, 1031 true /* open */)) { 1032 HeapShared::set_open_archive_heap_region_mapped(); 1033 } 1034 } 1035 } 1036 1037 void FileMapInfo::map_heap_regions() { 1038 if (has_heap_regions()) { 1039 map_heap_regions_impl(); 1040 } 1041 1042 if (!HeapShared::closed_archive_heap_region_mapped()) { 1043 assert(closed_archive_heap_ranges == NULL && 1044 num_closed_archive_heap_ranges == 0, "sanity"); 1045 } 1046 1047 if (!HeapShared::open_archive_heap_region_mapped()) { 1048 assert(open_archive_heap_ranges == NULL && num_open_archive_heap_ranges == 0, "sanity"); 1049 } 1050 } 1051 1052 bool FileMapInfo::map_heap_data(MemRegion **heap_mem, int first, 1053 int max, int* num, bool is_open_archive) { 1054 MemRegion * regions = new MemRegion[max]; 1055 CDSFileMapRegion* si; 1056 int region_num = 0; 1057 1058 for (int i = first; 1059 i < first + max; i++) { 1060 si = space_at(i); 1061 size_t size = si->_used; 1062 if (size > 0) { 1063 HeapWord* start = (HeapWord*)start_address_as_decoded_from_archive(si); 1064 regions[region_num] = MemRegion(start, size / HeapWordSize); 1065 region_num ++; 1066 log_info(cds)("Trying to map heap data: region[%d] at " INTPTR_FORMAT ", size = " SIZE_FORMAT_W(8) " bytes", 1067 i, p2i(start), size); 1068 } 1069 } 1070 1071 if (region_num == 0) { 1072 return false; // no archived java heap data 1073 } 1074 1075 // Check that ranges are within the java heap 1076 if (!G1CollectedHeap::heap()->check_archive_addresses(regions, region_num)) { 1077 log_info(cds)("UseSharedSpaces: Unable to allocate region, range is not within java heap."); 1078 return false; 1079 } 1080 1081 // allocate from java heap 1082 if (!G1CollectedHeap::heap()->alloc_archive_regions( 1083 regions, region_num, is_open_archive)) { 1084 log_info(cds)("UseSharedSpaces: Unable to allocate region, java heap range is already in use."); 1085 return false; 1086 } 1087 1088 // Map the archived heap data. No need to call MemTracker::record_virtual_memory_type() 1089 // for mapped regions as they are part of the reserved java heap, which is 1090 // already recorded. 1091 for (int i = 0; i < region_num; i++) { 1092 si = space_at(first + i); 1093 char* addr = (char*)regions[i].start(); 1094 char* base = os::map_memory(_fd, _full_path, si->_file_offset, 1095 addr, regions[i].byte_size(), si->_read_only, 1096 si->_allow_exec); 1097 if (base == NULL || base != addr) { 1098 // dealloc the regions from java heap 1099 dealloc_archive_heap_regions(regions, region_num, is_open_archive); 1100 log_info(cds)("UseSharedSpaces: Unable to map at required address in java heap. " 1101 INTPTR_FORMAT ", size = " SIZE_FORMAT " bytes", 1102 p2i(addr), regions[i].byte_size()); 1103 return false; 1104 } 1105 } 1106 1107 if (!verify_mapped_heap_regions(first, region_num)) { 1108 // dealloc the regions from java heap 1109 dealloc_archive_heap_regions(regions, region_num, is_open_archive); 1110 log_info(cds)("UseSharedSpaces: mapped heap regions are corrupt"); 1111 return false; 1112 } 1113 1114 // the shared heap data is mapped successfully 1115 *heap_mem = regions; 1116 *num = region_num; 1117 return true; 1118 } 1119 1120 bool FileMapInfo::verify_mapped_heap_regions(int first, int num) { 1121 assert(num > 0, "sanity"); 1122 for (int i = first; i < first + num; i++) { 1123 if (!verify_region_checksum(i)) { 1124 return false; 1125 } 1126 } 1127 return true; 1128 } 1129 1130 void FileMapInfo::patch_archived_heap_embedded_pointers() { 1131 if (!_heap_pointers_need_patching) { 1132 return; 1133 } 1134 1135 patch_archived_heap_embedded_pointers(closed_archive_heap_ranges, 1136 num_closed_archive_heap_ranges, 1137 MetaspaceShared::first_closed_archive_heap_region); 1138 1139 patch_archived_heap_embedded_pointers(open_archive_heap_ranges, 1140 num_open_archive_heap_ranges, 1141 MetaspaceShared::first_open_archive_heap_region); 1142 } 1143 1144 void FileMapInfo::patch_archived_heap_embedded_pointers(MemRegion* ranges, int num_ranges, 1145 int first_region_idx) { 1146 for (int i=0; i<num_ranges; i++) { 1147 CDSFileMapRegion* si = space_at(i + first_region_idx); 1148 HeapShared::patch_archived_heap_embedded_pointers(ranges[i], (address)si->_oopmap, 1149 si->_oopmap_size_in_bits); 1150 } 1151 } 1152 1153 // This internally allocates objects using SystemDictionary::Object_klass(), so it 1154 // must be called after the well-known classes are resolved. 1155 void FileMapInfo::fixup_mapped_heap_regions() { 1156 // If any closed regions were found, call the fill routine to make them parseable. 1157 // Note that closed_archive_heap_ranges may be non-NULL even if no ranges were found. 1158 if (num_closed_archive_heap_ranges != 0) { 1159 assert(closed_archive_heap_ranges != NULL, 1160 "Null closed_archive_heap_ranges array with non-zero count"); 1161 G1CollectedHeap::heap()->fill_archive_regions(closed_archive_heap_ranges, 1162 num_closed_archive_heap_ranges); 1163 } 1164 1165 // do the same for mapped open archive heap regions 1166 if (num_open_archive_heap_ranges != 0) { 1167 assert(open_archive_heap_ranges != NULL, "NULL open_archive_heap_ranges array with non-zero count"); 1168 G1CollectedHeap::heap()->fill_archive_regions(open_archive_heap_ranges, 1169 num_open_archive_heap_ranges); 1170 } 1171 } 1172 1173 // dealloc the archive regions from java heap 1174 void FileMapInfo::dealloc_archive_heap_regions(MemRegion* regions, int num, bool is_open) { 1175 if (num > 0) { 1176 assert(regions != NULL, "Null archive ranges array with non-zero count"); 1177 G1CollectedHeap::heap()->dealloc_archive_regions(regions, num, is_open); 1178 } 1179 } 1180 #endif // INCLUDE_CDS_JAVA_HEAP 1181 1182 bool FileMapInfo::verify_region_checksum(int i) { 1183 if (!VerifySharedSpaces) { 1184 return true; 1185 } 1186 1187 size_t sz = space_at(i)->_used; 1188 1189 if (sz == 0) { 1190 return true; // no data 1191 } 1192 if ((HeapShared::is_closed_archive_heap_region(i) && 1193 !HeapShared::closed_archive_heap_region_mapped()) || 1194 (HeapShared::is_open_archive_heap_region(i) && 1195 !HeapShared::open_archive_heap_region_mapped())) { 1196 return true; // archived heap data is not mapped 1197 } 1198 const char* buf = region_addr(i); 1199 int crc = ClassLoader::crc32(0, buf, (jint)sz); 1200 if (crc != space_at(i)->_crc) { 1201 fail_continue("Checksum verification failed."); 1202 return false; 1203 } 1204 return true; 1205 } 1206 1207 // Unmap a memory region in the address space. 1208 1209 void FileMapInfo::unmap_region(int i) { 1210 assert(!HeapShared::is_heap_region(i), "sanity"); 1211 CDSFileMapRegion* si = space_at(i); 1212 size_t used = si->_used; 1213 size_t size = align_up(used, os::vm_allocation_granularity()); 1214 1215 if (used == 0) { 1216 return; 1217 } 1218 1219 char* addr = region_addr(i); 1220 if (!os::unmap_memory(addr, size)) { 1221 fail_stop("Unable to unmap shared space."); 1222 } 1223 } 1224 1225 void FileMapInfo::assert_mark(bool check) { 1226 if (!check) { 1227 fail_stop("Mark mismatch while restoring from shared file."); 1228 } 1229 } 1230 1231 void FileMapInfo::metaspace_pointers_do(MetaspaceClosure* it) { 1232 it->push(&_shared_path_table); 1233 for (int i=0; i<_shared_path_table_size; i++) { 1234 shared_path(i)->metaspace_pointers_do(it); 1235 } 1236 } 1237 1238 1239 FileMapInfo* FileMapInfo::_current_info = NULL; 1240 bool FileMapInfo::_heap_pointers_need_patching = false; 1241 Array<u8>* FileMapInfo::_shared_path_table = NULL; 1242 int FileMapInfo::_shared_path_table_size = 0; 1243 size_t FileMapInfo::_shared_path_entry_size = 0x1234baad; 1244 bool FileMapInfo::_validating_shared_path_table = false; 1245 1246 // Open the shared archive file, read and validate the header 1247 // information (version, boot classpath, etc.). If initialization 1248 // fails, shared spaces are disabled and the file is closed. [See 1249 // fail_continue.] 1250 // 1251 // Validation of the archive is done in two steps: 1252 // 1253 // [1] validate_header() - done here. This checks the header, including _paths_misc_info. 1254 // [2] validate_shared_path_table - this is done later, because the table is in the RW 1255 // region of the archive, which is not mapped yet. 1256 bool FileMapInfo::initialize() { 1257 assert(UseSharedSpaces, "UseSharedSpaces expected."); 1258 1259 if (JvmtiExport::should_post_class_file_load_hook() && JvmtiExport::has_early_class_hook_env()) { 1260 // CDS assumes that no classes resolved in SystemDictionary::resolve_well_known_classes 1261 // are replaced at runtime by JVMTI ClassFileLoadHook. All of those classes are resolved 1262 // during the JVMTI "early" stage, so we can still use CDS if 1263 // JvmtiExport::has_early_class_hook_env() is false. 1264 FileMapInfo::fail_continue("CDS is disabled because early JVMTI ClassFileLoadHook is in use."); 1265 return false; 1266 } 1267 1268 if (!open_for_read()) { 1269 return false; 1270 } 1271 1272 init_from_file(_fd); 1273 if (!validate_header()) { 1274 return false; 1275 } 1276 return true; 1277 } 1278 1279 char* FileMapInfo::region_addr(int idx) { 1280 CDSFileMapRegion* si = space_at(idx); 1281 if (HeapShared::is_heap_region(idx)) { 1282 assert(DumpSharedSpaces, "The following doesn't work at runtime"); 1283 return si->_used > 0 ? 1284 (char*)start_address_as_decoded_with_current_oop_encoding_mode(si) : NULL; 1285 } else { 1286 return si->_addr._base; 1287 } 1288 } 1289 1290 int FileMapHeader::compute_crc() { 1291 char* start = (char*)this; 1292 // start computing from the field after _crc 1293 char* buf = (char*)&_crc + sizeof(_crc); 1294 size_t sz = sizeof(FileMapHeader) - (buf - start); 1295 int crc = ClassLoader::crc32(0, buf, (jint)sz); 1296 return crc; 1297 } 1298 1299 // This function should only be called during run time with UseSharedSpaces enabled. 1300 bool FileMapHeader::validate() { 1301 if (VerifySharedSpaces && compute_crc() != _crc) { 1302 FileMapInfo::fail_continue("Header checksum verification failed."); 1303 return false; 1304 } 1305 1306 if (!Arguments::has_jimage()) { 1307 FileMapInfo::fail_continue("The shared archive file cannot be used with an exploded module build."); 1308 return false; 1309 } 1310 1311 if (_version != CURRENT_CDS_ARCHIVE_VERSION) { 1312 FileMapInfo::fail_continue("The shared archive file is the wrong version."); 1313 return false; 1314 } 1315 if (_magic != CDS_ARCHIVE_MAGIC) { 1316 FileMapInfo::fail_continue("The shared archive file has a bad magic number."); 1317 return false; 1318 } 1319 char header_version[JVM_IDENT_MAX]; 1320 get_header_version(header_version); 1321 if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) { 1322 log_info(class, path)("expected: %s", header_version); 1323 log_info(class, path)("actual: %s", _jvm_ident); 1324 FileMapInfo::fail_continue("The shared archive file was created by a different" 1325 " version or build of HotSpot"); 1326 return false; 1327 } 1328 if (_obj_alignment != ObjectAlignmentInBytes) { 1329 FileMapInfo::fail_continue("The shared archive file's ObjectAlignmentInBytes of %d" 1330 " does not equal the current ObjectAlignmentInBytes of " INTX_FORMAT ".", 1331 _obj_alignment, ObjectAlignmentInBytes); 1332 return false; 1333 } 1334 if (_compact_strings != CompactStrings) { 1335 FileMapInfo::fail_continue("The shared archive file's CompactStrings setting (%s)" 1336 " does not equal the current CompactStrings setting (%s).", 1337 _compact_strings ? "enabled" : "disabled", 1338 CompactStrings ? "enabled" : "disabled"); 1339 return false; 1340 } 1341 1342 // This must be done after header validation because it might change the 1343 // header data 1344 const char* prop = Arguments::get_property("java.system.class.loader"); 1345 if (prop != NULL) { 1346 warning("Archived non-system classes are disabled because the " 1347 "java.system.class.loader property is specified (value = \"%s\"). " 1348 "To use archived non-system classes, this property must not be set", prop); 1349 _has_platform_or_app_classes = false; 1350 } 1351 1352 // For backwards compatibility, we don't check the verification setting 1353 // if the archive only contains system classes. 1354 if (_has_platform_or_app_classes && 1355 ((!_verify_local && BytecodeVerificationLocal) || 1356 (!_verify_remote && BytecodeVerificationRemote))) { 1357 FileMapInfo::fail_continue("The shared archive file was created with less restrictive " 1358 "verification setting than the current setting."); 1359 return false; 1360 } 1361 1362 // Java agents are allowed during run time. Therefore, the following condition is not 1363 // checked: (!_allow_archiving_with_java_agent && AllowArchivingWithJavaAgent) 1364 // Note: _allow_archiving_with_java_agent is set in the shared archive during dump time 1365 // while AllowArchivingWithJavaAgent is set during the current run. 1366 if (_allow_archiving_with_java_agent && !AllowArchivingWithJavaAgent) { 1367 FileMapInfo::fail_continue("The setting of the AllowArchivingWithJavaAgent is different " 1368 "from the setting in the shared archive."); 1369 return false; 1370 } 1371 1372 if (_allow_archiving_with_java_agent) { 1373 warning("This archive was created with AllowArchivingWithJavaAgent. It should be used " 1374 "for testing purposes only and should not be used in a production environment"); 1375 } 1376 1377 return true; 1378 } 1379 1380 bool FileMapInfo::validate_header() { 1381 bool status = _header->validate(); 1382 1383 if (status) { 1384 if (!ClassLoader::check_shared_paths_misc_info(_paths_misc_info, _header->_paths_misc_info_size)) { 1385 if (!PrintSharedArchiveAndExit) { 1386 fail_continue("shared class paths mismatch (hint: enable -Xlog:class+path=info to diagnose the failure)"); 1387 status = false; 1388 } 1389 } 1390 } 1391 1392 if (_paths_misc_info != NULL) { 1393 FREE_C_HEAP_ARRAY(char, _paths_misc_info); 1394 _paths_misc_info = NULL; 1395 } 1396 return status; 1397 } 1398 1399 // Check if a given address is within one of the shared regions 1400 bool FileMapInfo::is_in_shared_region(const void* p, int idx) { 1401 assert(idx == MetaspaceShared::ro || 1402 idx == MetaspaceShared::rw || 1403 idx == MetaspaceShared::mc || 1404 idx == MetaspaceShared::md, "invalid region index"); 1405 char* base = region_addr(idx); 1406 if (p >= base && p < base + space_at(idx)->_used) { 1407 return true; 1408 } 1409 return false; 1410 } 1411 1412 // Unmap mapped regions of shared space. 1413 void FileMapInfo::stop_sharing_and_unmap(const char* msg) { 1414 MetaspaceObj::set_shared_metaspace_range(NULL, NULL); 1415 1416 FileMapInfo *map_info = FileMapInfo::current_info(); 1417 if (map_info) { 1418 map_info->fail_continue("%s", msg); 1419 for (int i = 0; i < MetaspaceShared::num_non_heap_spaces; i++) { 1420 if (!HeapShared::is_heap_region(i)) { 1421 char *addr = map_info->region_addr(i); 1422 if (addr != NULL) { 1423 map_info->unmap_region(i); 1424 map_info->space_at(i)->_addr._base = NULL; 1425 } 1426 } 1427 } 1428 // Dealloc the archive heap regions only without unmapping. The regions are part 1429 // of the java heap. Unmapping of the heap regions are managed by GC. 1430 map_info->dealloc_archive_heap_regions(open_archive_heap_ranges, 1431 num_open_archive_heap_ranges, 1432 true); 1433 map_info->dealloc_archive_heap_regions(closed_archive_heap_ranges, 1434 num_closed_archive_heap_ranges, 1435 false); 1436 } else if (DumpSharedSpaces) { 1437 fail_stop("%s", msg); 1438 } 1439 }