1 /* 2 * Copyright (c) 2003, 2014, 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 "classfile/classLoader.hpp" 27 #include "classfile/sharedClassUtil.hpp" 28 #include "classfile/symbolTable.hpp" 29 #include "classfile/systemDictionaryShared.hpp" 30 #include "classfile/altHashing.hpp" 31 #include "memory/filemap.hpp" 32 #include "memory/metadataFactory.hpp" 33 #include "memory/oopFactory.hpp" 34 #include "oops/objArrayOop.hpp" 35 #include "runtime/arguments.hpp" 36 #include "runtime/java.hpp" 37 #include "runtime/os.hpp" 38 #include "services/memTracker.hpp" 39 #include "utilities/defaultStream.hpp" 40 41 # include <sys/stat.h> 42 # include <errno.h> 43 44 #ifndef O_BINARY // if defined (Win32) use binary files. 45 #define O_BINARY 0 // otherwise do nothing. 46 #endif 47 48 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC 49 extern address JVM_FunctionAtStart(); 50 extern address JVM_FunctionAtEnd(); 51 52 // Complain and stop. All error conditions occurring during the writing of 53 // an archive file should stop the process. Unrecoverable errors during 54 // the reading of the archive file should stop the process. 55 56 static void fail(const char *msg, va_list ap) { 57 // This occurs very early during initialization: tty is not initialized. 58 jio_fprintf(defaultStream::error_stream(), 59 "An error has occurred while processing the" 60 " shared archive file.\n"); 61 jio_vfprintf(defaultStream::error_stream(), msg, ap); 62 jio_fprintf(defaultStream::error_stream(), "\n"); 63 // Do not change the text of the below message because some tests check for it. 64 vm_exit_during_initialization("Unable to use shared archive.", NULL); 65 } 66 67 68 void FileMapInfo::fail_stop(const char *msg, ...) { 69 va_list ap; 70 va_start(ap, msg); 71 fail(msg, ap); // Never returns. 72 va_end(ap); // for completeness. 73 } 74 75 76 // Complain and continue. Recoverable errors during the reading of the 77 // archive file may continue (with sharing disabled). 78 // 79 // If we continue, then disable shared spaces and close the file. 80 81 void FileMapInfo::fail_continue(const char *msg, ...) { 82 va_list ap; 83 va_start(ap, msg); 84 MetaspaceShared::set_archive_loading_failed(); 85 if (PrintSharedArchiveAndExit && _validating_classpath_entry_table) { 86 // If we are doing PrintSharedArchiveAndExit and some of the classpath entries 87 // do not validate, we can still continue "limping" to validate the remaining 88 // entries. No need to quit. 89 tty->print("["); 90 tty->vprint(msg, ap); 91 tty->print_cr("]"); 92 } else { 93 if (RequireSharedSpaces) { 94 fail(msg, ap); 95 } else { 96 if (PrintSharedSpaces) { 97 tty->print_cr("UseSharedSpaces: %s", msg); 98 } 99 } 100 UseSharedSpaces = false; 101 assert(current_info() != NULL, "singleton must be registered"); 102 current_info()->close(); 103 } 104 va_end(ap); 105 } 106 107 // Fill in the fileMapInfo structure with data about this VM instance. 108 109 // This method copies the vm version info into header_version. If the version is too 110 // long then a truncated version, which has a hash code appended to it, is copied. 111 // 112 // Using a template enables this method to verify that header_version is an array of 113 // length JVM_IDENT_MAX. This ensures that the code that writes to the CDS file and 114 // the code that reads the CDS file will both use the same size buffer. Hence, will 115 // use identical truncation. This is necessary for matching of truncated versions. 116 template <int N> static void get_header_version(char (&header_version) [N]) { 117 assert(N == JVM_IDENT_MAX, "Bad header_version size"); 118 119 const char *vm_version = VM_Version::internal_vm_info_string(); 120 const int version_len = (int)strlen(vm_version); 121 122 if (version_len < (JVM_IDENT_MAX-1)) { 123 strcpy(header_version, vm_version); 124 125 } else { 126 // Get the hash value. Use a static seed because the hash needs to return the same 127 // value over multiple jvm invocations. 128 unsigned int hash = AltHashing::murmur3_32(8191, (const jbyte*)vm_version, version_len); 129 130 // Truncate the ident, saving room for the 8 hex character hash value. 131 strncpy(header_version, vm_version, JVM_IDENT_MAX-9); 132 133 // Append the hash code as eight hex digits. 134 sprintf(&header_version[JVM_IDENT_MAX-9], "%08x", hash); 135 header_version[JVM_IDENT_MAX-1] = 0; // Null terminate. 136 } 137 } 138 139 FileMapInfo::FileMapInfo() { 140 assert(_current_info == NULL, "must be singleton"); // not thread safe 141 _current_info = this; 142 memset(this, 0, sizeof(FileMapInfo)); 143 _file_offset = 0; 144 _file_open = false; 145 _header = SharedClassUtil::allocate_file_map_header(); 146 _header->_version = _invalid_version; 147 } 148 149 FileMapInfo::~FileMapInfo() { 150 assert(_current_info == this, "must be singleton"); // not thread safe 151 _current_info = NULL; 152 } 153 154 void FileMapInfo::populate_header(size_t alignment) { 155 _header->populate(this, alignment); 156 } 157 158 size_t FileMapInfo::FileMapHeader::data_size() { 159 return SharedClassUtil::file_map_header_size() - sizeof(FileMapInfo::FileMapHeaderBase); 160 } 161 162 void FileMapInfo::FileMapHeader::populate(FileMapInfo* mapinfo, size_t alignment) { 163 _magic = 0xf00baba2; 164 _version = _current_version; 165 _alignment = alignment; 166 _obj_alignment = ObjectAlignmentInBytes; 167 _classpath_entry_table_size = mapinfo->_classpath_entry_table_size; 168 _classpath_entry_table = mapinfo->_classpath_entry_table; 169 _classpath_entry_size = mapinfo->_classpath_entry_size; 170 171 // The following fields are for sanity checks for whether this archive 172 // will function correctly with this JVM and the bootclasspath it's 173 // invoked with. 174 175 // JVM version string ... changes on each build. 176 get_header_version(_jvm_ident); 177 } 178 179 void FileMapInfo::allocate_classpath_entry_table() { 180 int bytes = 0; 181 int count = 0; 182 char* strptr = NULL; 183 char* strptr_max = NULL; 184 Thread* THREAD = Thread::current(); 185 186 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data(); 187 size_t entry_size = SharedClassUtil::shared_class_path_entry_size(); 188 189 for (int pass=0; pass<2; pass++) { 190 ClassPathEntry *cpe = ClassLoader::classpath_entry(0); 191 192 for (int cur_entry = 0 ; cpe != NULL; cpe = cpe->next(), cur_entry++) { 193 const char *name = cpe->name(); 194 int name_bytes = (int)(strlen(name) + 1); 195 196 if (pass == 0) { 197 count ++; 198 bytes += (int)entry_size; 199 bytes += name_bytes; 200 if (TraceClassPaths || (TraceClassLoading && Verbose)) { 201 tty->print_cr("[Add main shared path (%s) %s]", (cpe->is_jar_file() ? "jar" : "dir"), name); 202 } 203 } else { 204 SharedClassPathEntry* ent = shared_classpath(cur_entry); 205 if (cpe->is_jar_file()) { 206 struct stat st; 207 if (os::stat(name, &st) != 0) { 208 // The file/dir must exist, or it would not have been added 209 // into ClassLoader::classpath_entry(). 210 // 211 // If we can't access a jar file in the boot path, then we can't 212 // make assumptions about where classes get loaded from. 213 FileMapInfo::fail_stop("Unable to open jar file %s.", name); 214 } 215 216 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error. 217 SharedClassUtil::update_shared_classpath(cpe, ent, st.st_mtime, st.st_size, THREAD); 218 } else { 219 ent->_filesize = -1; 220 if (!os::dir_is_empty(name)) { 221 ClassLoader::exit_with_path_failure("Cannot have non-empty directory in archived classpaths", name); 222 } 223 } 224 ent->_name = strptr; 225 if (strptr + name_bytes <= strptr_max) { 226 strncpy(strptr, name, (size_t)name_bytes); // name_bytes includes trailing 0. 227 strptr += name_bytes; 228 } else { 229 assert(0, "miscalculated buffer size"); 230 } 231 } 232 } 233 234 if (pass == 0) { 235 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error. 236 Array<u8>* arr = MetadataFactory::new_array<u8>(loader_data, (bytes + 7)/8, THREAD); 237 strptr = (char*)(arr->data()); 238 strptr_max = strptr + bytes; 239 SharedClassPathEntry* table = (SharedClassPathEntry*)strptr; 240 strptr += entry_size * count; 241 242 _classpath_entry_table_size = count; 243 _classpath_entry_table = table; 244 _classpath_entry_size = entry_size; 245 } 246 } 247 } 248 249 bool FileMapInfo::validate_classpath_entry_table() { 250 _validating_classpath_entry_table = true; 251 252 int count = _header->_classpath_entry_table_size; 253 254 _classpath_entry_table = _header->_classpath_entry_table; 255 _classpath_entry_size = _header->_classpath_entry_size; 256 257 for (int i=0; i<count; i++) { 258 SharedClassPathEntry* ent = shared_classpath(i); 259 struct stat st; 260 const char* name = ent->_name; 261 bool ok = true; 262 if (TraceClassPaths || (TraceClassLoading && Verbose)) { 263 tty->print_cr("[Checking shared classpath entry: %s]", name); 264 } 265 if (os::stat(name, &st) != 0) { 266 fail_continue("Required classpath entry does not exist: %s", name); 267 ok = false; 268 } else if (ent->is_dir()) { 269 if (!os::dir_is_empty(name)) { 270 fail_continue("directory is not empty: %s", name); 271 ok = false; 272 } 273 } else { 274 if (ent->_timestamp != st.st_mtime || 275 ent->_filesize != st.st_size) { 276 ok = false; 277 if (PrintSharedArchiveAndExit) { 278 fail_continue(ent->_timestamp != st.st_mtime ? 279 "Timestamp mismatch" : 280 "File size mismatch"); 281 } else { 282 fail_continue("A jar file is not the one used while building" 283 " the shared archive file: %s", name); 284 } 285 } 286 } 287 if (ok) { 288 if (TraceClassPaths || (TraceClassLoading && Verbose)) { 289 tty->print_cr("[ok]"); 290 } 291 } else if (!PrintSharedArchiveAndExit) { 292 _validating_classpath_entry_table = false; 293 return false; 294 } 295 } 296 297 _classpath_entry_table_size = _header->_classpath_entry_table_size; 298 _validating_classpath_entry_table = false; 299 return true; 300 } 301 302 303 // Read the FileMapInfo information from the file. 304 305 bool FileMapInfo::init_from_file(int fd) { 306 size_t sz = _header->data_size(); 307 char* addr = _header->data(); 308 size_t n = os::read(fd, addr, (unsigned int)sz); 309 if (n != sz) { 310 fail_continue("Unable to read the file header."); 311 return false; 312 } 313 if (_header->_version != current_version()) { 314 fail_continue("The shared archive file has the wrong version."); 315 return false; 316 } 317 318 size_t info_size = _header->_paths_misc_info_size; 319 _paths_misc_info = NEW_C_HEAP_ARRAY_RETURN_NULL(char, info_size, mtClass); 320 if (_paths_misc_info == NULL) { 321 fail_continue("Unable to read the file header."); 322 return false; 323 } 324 n = os::read(fd, _paths_misc_info, (unsigned int)info_size); 325 if (n != info_size) { 326 fail_continue("Unable to read the shared path info header."); 327 FREE_C_HEAP_ARRAY(char, _paths_misc_info, mtClass); 328 _paths_misc_info = NULL; 329 return false; 330 } 331 332 size_t len = lseek(fd, 0, SEEK_END); 333 struct FileMapInfo::FileMapHeader::space_info* si = 334 &_header->_space[MetaspaceShared::mc]; 335 if (si->_file_offset >= len || len - si->_file_offset < si->_used) { 336 fail_continue("The shared archive file has been truncated."); 337 return false; 338 } 339 340 _file_offset += (long)n; 341 return true; 342 } 343 344 345 // Read the FileMapInfo information from the file. 346 bool FileMapInfo::open_for_read() { 347 _full_path = Arguments::GetSharedArchivePath(); 348 int fd = open(_full_path, O_RDONLY | O_BINARY, 0); 349 if (fd < 0) { 350 if (errno == ENOENT) { 351 // Not locating the shared archive is ok. 352 fail_continue("Specified shared archive not found."); 353 } else { 354 fail_continue("Failed to open shared archive file (%s).", 355 strerror(errno)); 356 } 357 return false; 358 } 359 360 _fd = fd; 361 _file_open = true; 362 return true; 363 } 364 365 366 // Write the FileMapInfo information to the file. 367 368 void FileMapInfo::open_for_write() { 369 _full_path = Arguments::GetSharedArchivePath(); 370 if (PrintSharedSpaces) { 371 tty->print_cr("Dumping shared data to file: "); 372 tty->print_cr(" %s", _full_path); 373 } 374 375 #ifdef _WINDOWS // On Windows, need WRITE permission to remove the file. 376 chmod(_full_path, _S_IREAD | _S_IWRITE); 377 #endif 378 379 // Use remove() to delete the existing file because, on Unix, this will 380 // allow processes that have it open continued access to the file. 381 remove(_full_path); 382 int fd = open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444); 383 if (fd < 0) { 384 fail_stop("Unable to create shared archive file %s.", _full_path); 385 } 386 _fd = fd; 387 _file_offset = 0; 388 _file_open = true; 389 } 390 391 392 // Write the header to the file, seek to the next allocation boundary. 393 394 void FileMapInfo::write_header() { 395 int info_size = ClassLoader::get_shared_paths_misc_info_size(); 396 397 _header->_paths_misc_info_size = info_size; 398 399 align_file_position(); 400 size_t sz = _header->data_size(); 401 char* addr = _header->data(); 402 write_bytes(addr, (int)sz); // skip the C++ vtable 403 write_bytes(ClassLoader::get_shared_paths_misc_info(), info_size); 404 align_file_position(); 405 } 406 407 408 // Dump shared spaces to file. 409 410 void FileMapInfo::write_space(int i, Metaspace* space, bool read_only) { 411 align_file_position(); 412 size_t used = space->used_bytes_slow(Metaspace::NonClassType); 413 size_t capacity = space->capacity_bytes_slow(Metaspace::NonClassType); 414 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i]; 415 write_region(i, (char*)space->bottom(), used, capacity, read_only, false); 416 } 417 418 419 // Dump region to file. 420 421 void FileMapInfo::write_region(int region, char* base, size_t size, 422 size_t capacity, bool read_only, 423 bool allow_exec) { 424 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[region]; 425 426 if (_file_open) { 427 guarantee(si->_file_offset == _file_offset, "file offset mismatch."); 428 if (PrintSharedSpaces) { 429 tty->print_cr("Shared file region %d: 0x%6x bytes, addr " INTPTR_FORMAT 430 " file offset 0x%6x", region, size, base, _file_offset); 431 } 432 } else { 433 si->_file_offset = _file_offset; 434 } 435 si->_base = base; 436 si->_used = size; 437 si->_capacity = capacity; 438 si->_read_only = read_only; 439 si->_allow_exec = allow_exec; 440 si->_crc = ClassLoader::crc32(0, base, (jint)size); 441 write_bytes_aligned(base, (int)size); 442 } 443 444 445 // Dump bytes to file -- at the current file position. 446 447 void FileMapInfo::write_bytes(const void* buffer, int nbytes) { 448 if (_file_open) { 449 int n = ::write(_fd, buffer, nbytes); 450 if (n != nbytes) { 451 // It is dangerous to leave the corrupted shared archive file around, 452 // close and remove the file. See bug 6372906. 453 close(); 454 remove(_full_path); 455 fail_stop("Unable to write to shared archive file.", NULL); 456 } 457 } 458 _file_offset += nbytes; 459 } 460 461 462 // Align file position to an allocation unit boundary. 463 464 void FileMapInfo::align_file_position() { 465 size_t new_file_offset = align_size_up(_file_offset, 466 os::vm_allocation_granularity()); 467 if (new_file_offset != _file_offset) { 468 _file_offset = new_file_offset; 469 if (_file_open) { 470 // Seek one byte back from the target and write a byte to insure 471 // that the written file is the correct length. 472 _file_offset -= 1; 473 if (lseek(_fd, (long)_file_offset, SEEK_SET) < 0) { 474 fail_stop("Unable to seek.", NULL); 475 } 476 char zero = 0; 477 write_bytes(&zero, 1); 478 } 479 } 480 } 481 482 483 // Dump bytes to file -- at the current file position. 484 485 void FileMapInfo::write_bytes_aligned(const void* buffer, int nbytes) { 486 align_file_position(); 487 write_bytes(buffer, nbytes); 488 align_file_position(); 489 } 490 491 492 // Close the shared archive file. This does NOT unmap mapped regions. 493 494 void FileMapInfo::close() { 495 if (_file_open) { 496 if (::close(_fd) < 0) { 497 fail_stop("Unable to close the shared archive file."); 498 } 499 _file_open = false; 500 _fd = -1; 501 } 502 } 503 504 505 // JVM/TI RedefineClasses() support: 506 // Remap the shared readonly space to shared readwrite, private. 507 bool FileMapInfo::remap_shared_readonly_as_readwrite() { 508 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[0]; 509 if (!si->_read_only) { 510 // the space is already readwrite so we are done 511 return true; 512 } 513 size_t used = si->_used; 514 size_t size = align_size_up(used, os::vm_allocation_granularity()); 515 if (!open_for_read()) { 516 return false; 517 } 518 char *base = os::remap_memory(_fd, _full_path, si->_file_offset, 519 si->_base, size, false /* !read_only */, 520 si->_allow_exec); 521 close(); 522 if (base == NULL) { 523 fail_continue("Unable to remap shared readonly space (errno=%d).", errno); 524 return false; 525 } 526 if (base != si->_base) { 527 fail_continue("Unable to remap shared readonly space at required address."); 528 return false; 529 } 530 si->_read_only = false; 531 return true; 532 } 533 534 // Map the whole region at once, assumed to be allocated contiguously. 535 ReservedSpace FileMapInfo::reserve_shared_memory() { 536 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[0]; 537 char* requested_addr = si->_base; 538 539 size_t size = FileMapInfo::shared_spaces_size(); 540 541 // Reserve the space first, then map otherwise map will go right over some 542 // other reserved memory (like the code cache). 543 ReservedSpace rs(size, os::vm_allocation_granularity(), false, requested_addr); 544 if (!rs.is_reserved()) { 545 fail_continue(err_msg("Unable to reserve shared space at required address " INTPTR_FORMAT, requested_addr)); 546 return rs; 547 } 548 // the reserved virtual memory is for mapping class data sharing archive 549 MemTracker::record_virtual_memory_type((address)rs.base(), mtClassShared); 550 551 return rs; 552 } 553 554 // Memory map a region in the address space. 555 static const char* shared_region_name[] = { "ReadOnly", "ReadWrite", "MiscData", "MiscCode"}; 556 557 char* FileMapInfo::map_region(int i) { 558 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i]; 559 size_t used = si->_used; 560 size_t alignment = os::vm_allocation_granularity(); 561 size_t size = align_size_up(used, alignment); 562 char *requested_addr = si->_base; 563 564 // map the contents of the CDS archive in this memory 565 char *base = os::map_memory(_fd, _full_path, si->_file_offset, 566 requested_addr, size, si->_read_only, 567 si->_allow_exec); 568 if (base == NULL || base != si->_base) { 569 fail_continue(err_msg("Unable to map %s shared space at required address.", shared_region_name[i])); 570 return NULL; 571 } 572 #ifdef _WINDOWS 573 // This call is Windows-only because the memory_type gets recorded for the other platforms 574 // in method FileMapInfo::reserve_shared_memory(), which is not called on Windows. 575 MemTracker::record_virtual_memory_type((address)base, mtClassShared); 576 #endif 577 return base; 578 } 579 580 bool FileMapInfo::verify_region_checksum(int i) { 581 if (!VerifySharedSpaces) { 582 return true; 583 } 584 const char* buf = _header->_space[i]._base; 585 size_t sz = _header->_space[i]._used; 586 int crc = ClassLoader::crc32(0, buf, (jint)sz); 587 if (crc != _header->_space[i]._crc) { 588 fail_continue("Checksum verification failed."); 589 return false; 590 } 591 return true; 592 } 593 594 // Unmap a memory region in the address space. 595 596 void FileMapInfo::unmap_region(int i) { 597 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i]; 598 size_t used = si->_used; 599 size_t size = align_size_up(used, os::vm_allocation_granularity()); 600 if (!os::unmap_memory(si->_base, size)) { 601 fail_stop("Unable to unmap shared space."); 602 } 603 } 604 605 606 void FileMapInfo::assert_mark(bool check) { 607 if (!check) { 608 fail_stop("Mark mismatch while restoring from shared file.", NULL); 609 } 610 } 611 612 613 FileMapInfo* FileMapInfo::_current_info = NULL; 614 SharedClassPathEntry* FileMapInfo::_classpath_entry_table = NULL; 615 int FileMapInfo::_classpath_entry_table_size = 0; 616 size_t FileMapInfo::_classpath_entry_size = 0x1234baad; 617 bool FileMapInfo::_validating_classpath_entry_table = false; 618 619 // Open the shared archive file, read and validate the header 620 // information (version, boot classpath, etc.). If initialization 621 // fails, shared spaces are disabled and the file is closed. [See 622 // fail_continue.] 623 // 624 // Validation of the archive is done in two steps: 625 // 626 // [1] validate_header() - done here. This checks the header, including _paths_misc_info. 627 // [2] validate_classpath_entry_table - this is done later, because the table is in the RW 628 // region of the archive, which is not mapped yet. 629 bool FileMapInfo::initialize() { 630 assert(UseSharedSpaces, "UseSharedSpaces expected."); 631 632 if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space()) { 633 fail_continue("Tool agent requires sharing to be disabled."); 634 return false; 635 } 636 637 if (!open_for_read()) { 638 return false; 639 } 640 641 init_from_file(_fd); 642 if (!validate_header()) { 643 return false; 644 } 645 646 SharedReadOnlySize = _header->_space[0]._capacity; 647 SharedReadWriteSize = _header->_space[1]._capacity; 648 SharedMiscDataSize = _header->_space[2]._capacity; 649 SharedMiscCodeSize = _header->_space[3]._capacity; 650 return true; 651 } 652 653 int FileMapInfo::FileMapHeader::compute_crc() { 654 char* header = data(); 655 // start computing from the field after _crc 656 char* buf = (char*)&_crc + sizeof(int); 657 size_t sz = data_size() - (buf - header); 658 int crc = ClassLoader::crc32(0, buf, (jint)sz); 659 return crc; 660 } 661 662 int FileMapInfo::compute_header_crc() { 663 return _header->compute_crc(); 664 } 665 666 bool FileMapInfo::FileMapHeader::validate() { 667 if (_magic != (int)0xf00baba2) { 668 FileMapInfo::fail_continue("The shared archive file has a bad magic number."); 669 return false; 670 } 671 if (VerifySharedSpaces && compute_crc() != _crc) { 672 fail_continue("Header checksum verification failed."); 673 return false; 674 } 675 if (_version != current_version()) { 676 FileMapInfo::fail_continue("The shared archive file is the wrong version."); 677 678 return false; 679 } 680 char header_version[JVM_IDENT_MAX]; 681 get_header_version(header_version); 682 if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) { 683 if (TraceClassPaths) { 684 tty->print_cr("Expected: %s", header_version); 685 tty->print_cr("Actual: %s", _jvm_ident); 686 } 687 FileMapInfo::fail_continue("The shared archive file was created by a different" 688 " version or build of HotSpot"); 689 return false; 690 } 691 if (_obj_alignment != ObjectAlignmentInBytes) { 692 FileMapInfo::fail_continue("The shared archive file's ObjectAlignmentInBytes of %d" 693 " does not equal the current ObjectAlignmentInBytes of %d.", 694 _obj_alignment, ObjectAlignmentInBytes); 695 return false; 696 } 697 698 return true; 699 } 700 701 bool FileMapInfo::validate_header() { 702 bool status = _header->validate(); 703 704 if (status) { 705 if (!ClassLoader::check_shared_paths_misc_info(_paths_misc_info, _header->_paths_misc_info_size)) { 706 if (!PrintSharedArchiveAndExit) { 707 fail_continue("shared class paths mismatch (hint: enable -XX:+TraceClassPaths to diagnose the failure)"); 708 status = false; 709 } 710 } 711 } 712 713 if (_paths_misc_info != NULL) { 714 FREE_C_HEAP_ARRAY(char, _paths_misc_info, mtClass); 715 _paths_misc_info = NULL; 716 } 717 return status; 718 } 719 720 // The following method is provided to see whether a given pointer 721 // falls in the mapped shared space. 722 // Param: 723 // p, The given pointer 724 // Return: 725 // True if the p is within the mapped shared space, otherwise, false. 726 bool FileMapInfo::is_in_shared_space(const void* p) { 727 for (int i = 0; i < MetaspaceShared::n_regions; i++) { 728 if (p >= _header->_space[i]._base && 729 p < _header->_space[i]._base + _header->_space[i]._used) { 730 return true; 731 } 732 } 733 734 return false; 735 } 736 737 void FileMapInfo::print_shared_spaces() { 738 gclog_or_tty->print_cr("Shared Spaces:"); 739 for (int i = 0; i < MetaspaceShared::n_regions; i++) { 740 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i]; 741 gclog_or_tty->print(" %s " INTPTR_FORMAT "-" INTPTR_FORMAT, 742 shared_region_name[i], 743 si->_base, si->_base + si->_used); 744 } 745 } 746 747 // Unmap mapped regions of shared space. 748 void FileMapInfo::stop_sharing_and_unmap(const char* msg) { 749 FileMapInfo *map_info = FileMapInfo::current_info(); 750 if (map_info) { 751 map_info->fail_continue(msg); 752 for (int i = 0; i < MetaspaceShared::n_regions; i++) { 753 if (map_info->_header->_space[i]._base != NULL) { 754 map_info->unmap_region(i); 755 map_info->_header->_space[i]._base = NULL; 756 } 757 } 758 } else if (DumpSharedSpaces) { 759 fail_stop(msg, NULL); 760 } 761 }