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