1 /* 2 * Copyright (c) 2003, 2016, 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/compactHashtable.inline.hpp" 28 #include "classfile/sharedClassUtil.hpp" 29 #include "classfile/symbolTable.hpp" 30 #include "classfile/systemDictionaryShared.hpp" 31 #include "classfile/altHashing.hpp" 32 #if INCLUDE_ALL_GCS 33 #include "gc/g1/g1CollectedHeap.hpp" 34 #endif 35 #include "memory/filemap.hpp" 36 #include "memory/metadataFactory.hpp" 37 #include "memory/oopFactory.hpp" 38 #include "oops/objArrayOop.hpp" 39 #include "prims/jvmtiExport.hpp" 40 #include "runtime/arguments.hpp" 41 #include "runtime/java.hpp" 42 #include "runtime/os.hpp" 43 #include "runtime/vm_version.hpp" 44 #include "services/memTracker.hpp" 45 #include "utilities/defaultStream.hpp" 46 47 # include <sys/stat.h> 48 # include <errno.h> 49 50 #ifndef O_BINARY // if defined (Win32) use binary files. 51 #define O_BINARY 0 // otherwise do nothing. 52 #endif 53 54 extern address JVM_FunctionAtStart(); 55 extern address JVM_FunctionAtEnd(); 56 57 // Complain and stop. All error conditions occurring during the writing of 58 // an archive file should stop the process. Unrecoverable errors during 59 // the reading of the archive file should stop the process. 60 61 static void fail(const char *msg, va_list ap) { 62 // This occurs very early during initialization: tty is not initialized. 63 jio_fprintf(defaultStream::error_stream(), 64 "An error has occurred while processing the" 65 " shared archive file.\n"); 66 jio_vfprintf(defaultStream::error_stream(), msg, ap); 67 jio_fprintf(defaultStream::error_stream(), "\n"); 68 // Do not change the text of the below message because some tests check for it. 69 vm_exit_during_initialization("Unable to use shared archive.", NULL); 70 } 71 72 73 void FileMapInfo::fail_stop(const char *msg, ...) { 74 va_list ap; 75 va_start(ap, msg); 76 fail(msg, ap); // Never returns. 77 va_end(ap); // for completeness. 78 } 79 80 81 // Complain and continue. Recoverable errors during the reading of the 82 // archive file may continue (with sharing disabled). 83 // 84 // If we continue, then disable shared spaces and close the file. 85 86 void FileMapInfo::fail_continue(const char *msg, ...) { 87 va_list ap; 88 va_start(ap, msg); 89 MetaspaceShared::set_archive_loading_failed(); 90 if (PrintSharedArchiveAndExit && _validating_classpath_entry_table) { 91 // If we are doing PrintSharedArchiveAndExit and some of the classpath entries 92 // do not validate, we can still continue "limping" to validate the remaining 93 // entries. No need to quit. 94 tty->print("["); 95 tty->vprint(msg, ap); 96 tty->print_cr("]"); 97 } else { 98 if (RequireSharedSpaces) { 99 fail(msg, ap); 100 } else { 101 if (PrintSharedSpaces) { 102 tty->print_cr("UseSharedSpaces: %s", msg); 103 } 104 } 105 UseSharedSpaces = false; 106 assert(current_info() != NULL, "singleton must be registered"); 107 current_info()->close(); 108 } 109 va_end(ap); 110 } 111 112 // Fill in the fileMapInfo structure with data about this VM instance. 113 114 // This method copies the vm version info into header_version. If the version is too 115 // long then a truncated version, which has a hash code appended to it, is copied. 116 // 117 // Using a template enables this method to verify that header_version is an array of 118 // length JVM_IDENT_MAX. This ensures that the code that writes to the CDS file and 119 // the code that reads the CDS file will both use the same size buffer. Hence, will 120 // use identical truncation. This is necessary for matching of truncated versions. 121 template <int N> static void get_header_version(char (&header_version) [N]) { 122 assert(N == JVM_IDENT_MAX, "Bad header_version size"); 123 124 const char *vm_version = VM_Version::internal_vm_info_string(); 125 const int version_len = (int)strlen(vm_version); 126 127 if (version_len < (JVM_IDENT_MAX-1)) { 128 strcpy(header_version, vm_version); 129 130 } else { 131 // Get the hash value. Use a static seed because the hash needs to return the same 132 // value over multiple jvm invocations. 133 unsigned int hash = AltHashing::murmur3_32(8191, (const jbyte*)vm_version, version_len); 134 135 // Truncate the ident, saving room for the 8 hex character hash value. 136 strncpy(header_version, vm_version, JVM_IDENT_MAX-9); 137 138 // Append the hash code as eight hex digits. 139 sprintf(&header_version[JVM_IDENT_MAX-9], "%08x", hash); 140 header_version[JVM_IDENT_MAX-1] = 0; // Null terminate. 141 } 142 } 143 144 FileMapInfo::FileMapInfo() { 145 assert(_current_info == NULL, "must be singleton"); // not thread safe 146 _current_info = this; 147 memset(this, 0, sizeof(FileMapInfo)); 148 _file_offset = 0; 149 _file_open = false; 150 _header = SharedClassUtil::allocate_file_map_header(); 151 _header->_version = _invalid_version; 152 } 153 154 FileMapInfo::~FileMapInfo() { 155 assert(_current_info == this, "must be singleton"); // not thread safe 156 _current_info = NULL; 157 } 158 159 void FileMapInfo::populate_header(size_t alignment) { 160 _header->populate(this, alignment); 161 } 162 163 size_t FileMapInfo::FileMapHeader::data_size() { 164 return SharedClassUtil::file_map_header_size() - sizeof(FileMapInfo::FileMapHeaderBase); 165 } 166 167 void FileMapInfo::FileMapHeader::populate(FileMapInfo* mapinfo, size_t alignment) { 168 _magic = 0xf00baba2; 169 _version = _current_version; 170 _alignment = alignment; 171 _obj_alignment = ObjectAlignmentInBytes; 172 _compact_strings = CompactStrings; 173 _narrow_oop_mode = Universe::narrow_oop_mode(); 174 _narrow_oop_shift = Universe::narrow_oop_shift(); 175 _max_heap_size = MaxHeapSize; 176 _narrow_klass_base = Universe::narrow_klass_base(); 177 _narrow_klass_shift = Universe::narrow_klass_shift(); 178 _classpath_entry_table_size = mapinfo->_classpath_entry_table_size; 179 _classpath_entry_table = mapinfo->_classpath_entry_table; 180 _classpath_entry_size = mapinfo->_classpath_entry_size; 181 182 // The following fields are for sanity checks for whether this archive 183 // will function correctly with this JVM and the bootclasspath it's 184 // invoked with. 185 186 // JVM version string ... changes on each build. 187 get_header_version(_jvm_ident); 188 } 189 190 void FileMapInfo::allocate_classpath_entry_table() { 191 int bytes = 0; 192 int count = 0; 193 char* strptr = NULL; 194 char* strptr_max = NULL; 195 Thread* THREAD = Thread::current(); 196 197 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data(); 198 size_t entry_size = SharedClassUtil::shared_class_path_entry_size(); 199 200 for (int pass=0; pass<2; pass++) { 201 ClassPathEntry *cpe = ClassLoader::classpath_entry(0); 202 203 for (int cur_entry = 0 ; cpe != NULL; cpe = cpe->next(), cur_entry++) { 204 const char *name = cpe->name(); 205 int name_bytes = (int)(strlen(name) + 1); 206 207 if (pass == 0) { 208 count ++; 209 bytes += (int)entry_size; 210 bytes += name_bytes; 211 log_info(classpath)("add main shared path (%s) %s", (cpe->is_jar_file() ? "jar" : "dir"), name); 212 } else { 213 SharedClassPathEntry* ent = shared_classpath(cur_entry); 214 if (cpe->is_jar_file()) { 215 struct stat st; 216 if (os::stat(name, &st) != 0) { 217 // The file/dir must exist, or it would not have been added 218 // into ClassLoader::classpath_entry(). 219 // 220 // If we can't access a jar file in the boot path, then we can't 221 // make assumptions about where classes get loaded from. 222 FileMapInfo::fail_stop("Unable to open jar file %s.", name); 223 } 224 225 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error. 226 SharedClassUtil::update_shared_classpath(cpe, ent, st.st_mtime, st.st_size, THREAD); 227 } else { 228 struct stat st; 229 if ((os::stat(name, &st) == 0) && ((st.st_mode & S_IFDIR) == S_IFDIR)) { 230 if (!os::dir_is_empty(name)) { 231 ClassLoader::exit_with_path_failure("Cannot have non-empty directory in archived classpaths", name); 232 } 233 ent->_filesize = -1; 234 } else { 235 ent->_filesize = -2; 236 } 237 } 238 ent->_name = strptr; 239 if (strptr + name_bytes <= strptr_max) { 240 strncpy(strptr, name, (size_t)name_bytes); // name_bytes includes trailing 0. 241 strptr += name_bytes; 242 } else { 243 assert(0, "miscalculated buffer size"); 244 } 245 } 246 } 247 248 if (pass == 0) { 249 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error. 250 Array<u8>* arr = MetadataFactory::new_array<u8>(loader_data, (bytes + 7)/8, THREAD); 251 strptr = (char*)(arr->data()); 252 strptr_max = strptr + bytes; 253 SharedClassPathEntry* table = (SharedClassPathEntry*)strptr; 254 strptr += entry_size * count; 255 256 _classpath_entry_table_size = count; 257 _classpath_entry_table = table; 258 _classpath_entry_size = entry_size; 259 } 260 } 261 } 262 263 bool FileMapInfo::validate_classpath_entry_table() { 264 _validating_classpath_entry_table = true; 265 266 int count = _header->_classpath_entry_table_size; 267 268 _classpath_entry_table = _header->_classpath_entry_table; 269 _classpath_entry_size = _header->_classpath_entry_size; 270 271 for (int i=0; i<count; i++) { 272 SharedClassPathEntry* ent = shared_classpath(i); 273 struct stat st; 274 const char* name = ent->_name; 275 bool ok = true; 276 log_info(classpath)("checking shared classpath entry: %s", name); 277 if (os::stat(name, &st) != 0) { 278 fail_continue("Required classpath entry does not exist: %s", name); 279 ok = false; 280 } else if (ent->is_dir()) { 281 if (!os::dir_is_empty(name)) { 282 fail_continue("directory is not empty: %s", name); 283 ok = false; 284 } 285 } else if (ent->is_jar()) { 286 if (ent->_timestamp != st.st_mtime || 287 ent->_filesize != st.st_size) { 288 ok = false; 289 if (PrintSharedArchiveAndExit) { 290 fail_continue(ent->_timestamp != st.st_mtime ? 291 "Timestamp mismatch" : 292 "File size mismatch"); 293 } else { 294 fail_continue("A jar file is not the one used while building" 295 " the shared archive file: %s", name); 296 } 297 } 298 } 299 if (ok) { 300 log_info(classpath)("ok"); 301 } else if (!PrintSharedArchiveAndExit) { 302 _validating_classpath_entry_table = false; 303 return false; 304 } 305 } 306 307 _classpath_entry_table_size = _header->_classpath_entry_table_size; 308 _validating_classpath_entry_table = false; 309 return true; 310 } 311 312 313 // Read the FileMapInfo information from the file. 314 315 bool FileMapInfo::init_from_file(int fd) { 316 size_t sz = _header->data_size(); 317 char* addr = _header->data(); 318 size_t n = os::read(fd, addr, (unsigned int)sz); 319 if (n != sz) { 320 fail_continue("Unable to read the file header."); 321 return false; 322 } 323 if (_header->_version != current_version()) { 324 fail_continue("The shared archive file has the wrong version."); 325 return false; 326 } 327 _file_offset = (long)n; 328 329 size_t info_size = _header->_paths_misc_info_size; 330 _paths_misc_info = NEW_C_HEAP_ARRAY_RETURN_NULL(char, info_size, mtClass); 331 if (_paths_misc_info == NULL) { 332 fail_continue("Unable to read the file header."); 333 return false; 334 } 335 n = os::read(fd, _paths_misc_info, (unsigned int)info_size); 336 if (n != info_size) { 337 fail_continue("Unable to read the shared path info header."); 338 FREE_C_HEAP_ARRAY(char, _paths_misc_info); 339 _paths_misc_info = NULL; 340 return false; 341 } 342 343 size_t len = lseek(fd, 0, SEEK_END); 344 struct FileMapInfo::FileMapHeader::space_info* si = 345 &_header->_space[MetaspaceShared::mc]; 346 if (si->_file_offset >= len || len - si->_file_offset < si->_used) { 347 fail_continue("The shared archive file has been truncated."); 348 return false; 349 } 350 351 _file_offset += (long)n; 352 return true; 353 } 354 355 356 // Read the FileMapInfo information from the file. 357 bool FileMapInfo::open_for_read() { 358 _full_path = Arguments::GetSharedArchivePath(); 359 int fd = open(_full_path, O_RDONLY | O_BINARY, 0); 360 if (fd < 0) { 361 if (errno == ENOENT) { 362 // Not locating the shared archive is ok. 363 fail_continue("Specified shared archive not found."); 364 } else { 365 fail_continue("Failed to open shared archive file (%s).", 366 strerror(errno)); 367 } 368 return false; 369 } 370 371 _fd = fd; 372 _file_open = true; 373 return true; 374 } 375 376 377 // Write the FileMapInfo information to the file. 378 379 void FileMapInfo::open_for_write() { 380 _full_path = Arguments::GetSharedArchivePath(); 381 if (PrintSharedSpaces) { 382 tty->print_cr("Dumping shared data to file: "); 383 tty->print_cr(" %s", _full_path); 384 } 385 386 #ifdef _WINDOWS // On Windows, need WRITE permission to remove the file. 387 chmod(_full_path, _S_IREAD | _S_IWRITE); 388 #endif 389 390 // Use remove() to delete the existing file because, on Unix, this will 391 // allow processes that have it open continued access to the file. 392 remove(_full_path); 393 int fd = open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444); 394 if (fd < 0) { 395 fail_stop("Unable to create shared archive file %s: (%s).", _full_path, 396 strerror(errno)); 397 } 398 _fd = fd; 399 _file_offset = 0; 400 _file_open = true; 401 } 402 403 404 // Write the header to the file, seek to the next allocation boundary. 405 406 void FileMapInfo::write_header() { 407 int info_size = ClassLoader::get_shared_paths_misc_info_size(); 408 409 _header->_paths_misc_info_size = info_size; 410 411 align_file_position(); 412 size_t sz = _header->data_size(); 413 char* addr = _header->data(); 414 write_bytes(addr, (int)sz); // skip the C++ vtable 415 write_bytes(ClassLoader::get_shared_paths_misc_info(), info_size); 416 align_file_position(); 417 } 418 419 420 // Dump shared spaces to file. 421 422 void FileMapInfo::write_space(int i, Metaspace* space, bool read_only) { 423 align_file_position(); 424 size_t used = space->used_bytes_slow(Metaspace::NonClassType); 425 size_t capacity = space->capacity_bytes_slow(Metaspace::NonClassType); 426 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i]; 427 write_region(i, (char*)space->bottom(), used, capacity, read_only, false); 428 } 429 430 431 // Dump region to file. 432 433 void FileMapInfo::write_region(int region, char* base, size_t size, 434 size_t capacity, bool read_only, 435 bool allow_exec) { 436 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[region]; 437 438 if (_file_open) { 439 guarantee(si->_file_offset == _file_offset, "file offset mismatch."); 440 if (PrintSharedSpaces) { 441 tty->print_cr("Shared file region %d: " SIZE_FORMAT_HEX_W(6) " bytes, addr " INTPTR_FORMAT 442 " file offset " SIZE_FORMAT_HEX_W(6), region, size, p2i(base), _file_offset); 443 } 444 } else { 445 si->_file_offset = _file_offset; 446 } 447 if (MetaspaceShared::is_string_region(region)) { 448 assert((base - (char*)Universe::narrow_oop_base()) % HeapWordSize == 0, "Sanity"); 449 if (base != NULL) { 450 si->_addr._offset = (intx)oopDesc::encode_heap_oop_not_null((oop)base); 451 } else { 452 si->_addr._offset = 0; 453 } 454 } else { 455 si->_addr._base = base; 456 } 457 si->_used = size; 458 si->_capacity = capacity; 459 si->_read_only = read_only; 460 si->_allow_exec = allow_exec; 461 si->_crc = ClassLoader::crc32(0, base, (jint)size); 462 write_bytes_aligned(base, (int)size); 463 } 464 465 // Write the string space. The string space contains one or multiple GC(G1) regions. 466 // When the total string space size is smaller than one GC region of the dump time, 467 // only one string region is used for shared strings. 468 // 469 // If the total string space size is bigger than one GC region, there would be more 470 // than one GC regions allocated for shared strings. The first/bottom GC region might 471 // be a partial GC region with the empty portion at the higher address within that region. 472 // The non-empty portion of the first region is written into the archive as one string 473 // region. The rest are consecutive full GC regions if they exist, which can be written 474 // out in one chunk as another string region. 475 void FileMapInfo::write_string_regions(GrowableArray<MemRegion> *regions) { 476 for (int i = MetaspaceShared::first_string; 477 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) { 478 char* start = NULL; 479 size_t size = 0; 480 if (regions->is_nonempty()) { 481 if (i == MetaspaceShared::first_string) { 482 MemRegion first = regions->first(); 483 start = (char*)first.start(); 484 size = first.byte_size(); 485 } else { 486 int len = regions->length(); 487 if (len > 1) { 488 start = (char*)regions->at(1).start(); 489 size = (char*)regions->at(len - 1).end() - start; 490 } 491 } 492 } 493 write_region(i, start, size, size, false, false); 494 } 495 } 496 497 498 // Dump bytes to file -- at the current file position. 499 500 void FileMapInfo::write_bytes(const void* buffer, int nbytes) { 501 if (_file_open) { 502 int n = ::write(_fd, buffer, nbytes); 503 if (n != nbytes) { 504 // It is dangerous to leave the corrupted shared archive file around, 505 // close and remove the file. See bug 6372906. 506 close(); 507 remove(_full_path); 508 fail_stop("Unable to write to shared archive file."); 509 } 510 } 511 _file_offset += nbytes; 512 } 513 514 515 // Align file position to an allocation unit boundary. 516 517 void FileMapInfo::align_file_position() { 518 size_t new_file_offset = align_size_up(_file_offset, 519 os::vm_allocation_granularity()); 520 if (new_file_offset != _file_offset) { 521 _file_offset = new_file_offset; 522 if (_file_open) { 523 // Seek one byte back from the target and write a byte to insure 524 // that the written file is the correct length. 525 _file_offset -= 1; 526 if (lseek(_fd, (long)_file_offset, SEEK_SET) < 0) { 527 fail_stop("Unable to seek."); 528 } 529 char zero = 0; 530 write_bytes(&zero, 1); 531 } 532 } 533 } 534 535 536 // Dump bytes to file -- at the current file position. 537 538 void FileMapInfo::write_bytes_aligned(const void* buffer, int nbytes) { 539 align_file_position(); 540 write_bytes(buffer, nbytes); 541 align_file_position(); 542 } 543 544 545 // Close the shared archive file. This does NOT unmap mapped regions. 546 547 void FileMapInfo::close() { 548 if (_file_open) { 549 if (::close(_fd) < 0) { 550 fail_stop("Unable to close the shared archive file."); 551 } 552 _file_open = false; 553 _fd = -1; 554 } 555 } 556 557 558 // JVM/TI RedefineClasses() support: 559 // Remap the shared readonly space to shared readwrite, private. 560 bool FileMapInfo::remap_shared_readonly_as_readwrite() { 561 int idx = 0; 562 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[idx]; 563 if (!si->_read_only) { 564 // the space is already readwrite so we are done 565 return true; 566 } 567 size_t used = si->_used; 568 size_t size = align_size_up(used, os::vm_allocation_granularity()); 569 if (!open_for_read()) { 570 return false; 571 } 572 char *addr = _header->region_addr(idx); 573 char *base = os::remap_memory(_fd, _full_path, si->_file_offset, 574 addr, size, false /* !read_only */, 575 si->_allow_exec); 576 close(); 577 if (base == NULL) { 578 fail_continue("Unable to remap shared readonly space (errno=%d).", errno); 579 return false; 580 } 581 if (base != addr) { 582 fail_continue("Unable to remap shared readonly space at required address."); 583 return false; 584 } 585 si->_read_only = false; 586 return true; 587 } 588 589 // Map the whole region at once, assumed to be allocated contiguously. 590 ReservedSpace FileMapInfo::reserve_shared_memory() { 591 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[0]; 592 char* requested_addr = _header->region_addr(0); 593 594 size_t size = FileMapInfo::shared_spaces_size(); 595 596 // Reserve the space first, then map otherwise map will go right over some 597 // other reserved memory (like the code cache). 598 ReservedSpace rs(size, os::vm_allocation_granularity(), false, requested_addr); 599 if (!rs.is_reserved()) { 600 fail_continue("Unable to reserve shared space at required address " 601 INTPTR_FORMAT, p2i(requested_addr)); 602 return rs; 603 } 604 // the reserved virtual memory is for mapping class data sharing archive 605 MemTracker::record_virtual_memory_type((address)rs.base(), mtClassShared); 606 607 return rs; 608 } 609 610 // Memory map a region in the address space. 611 static const char* shared_region_name[] = { "ReadOnly", "ReadWrite", "MiscData", "MiscCode", 612 "String1", "String2" }; 613 614 char* FileMapInfo::map_region(int i) { 615 assert(!MetaspaceShared::is_string_region(i), "sanity"); 616 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i]; 617 size_t used = si->_used; 618 size_t alignment = os::vm_allocation_granularity(); 619 size_t size = align_size_up(used, alignment); 620 char *requested_addr = _header->region_addr(i); 621 622 // If a tool agent is in use (debugging enabled), we must map the address space RW 623 if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space()) { 624 si->_read_only = false; 625 } 626 627 // map the contents of the CDS archive in this memory 628 char *base = os::map_memory(_fd, _full_path, si->_file_offset, 629 requested_addr, size, si->_read_only, 630 si->_allow_exec); 631 if (base == NULL || base != requested_addr) { 632 fail_continue("Unable to map %s shared space at required address.", shared_region_name[i]); 633 return NULL; 634 } 635 #ifdef _WINDOWS 636 // This call is Windows-only because the memory_type gets recorded for the other platforms 637 // in method FileMapInfo::reserve_shared_memory(), which is not called on Windows. 638 MemTracker::record_virtual_memory_type((address)base, mtClassShared); 639 #endif 640 641 return base; 642 } 643 644 static MemRegion *string_ranges = NULL; 645 static int num_ranges = 0; 646 bool FileMapInfo::map_string_regions() { 647 #if INCLUDE_ALL_GCS 648 if (UseG1GC && UseCompressedOops && UseCompressedClassPointers) { 649 // Check that all the narrow oop and klass encodings match the archive 650 if (narrow_oop_mode() != Universe::narrow_oop_mode() || 651 narrow_oop_shift() != Universe::narrow_oop_shift() || 652 narrow_klass_base() != Universe::narrow_klass_base() || 653 narrow_klass_shift() != Universe::narrow_klass_shift()) { 654 if (PrintSharedSpaces && _header->_space[MetaspaceShared::first_string]._used > 0) { 655 tty->print_cr("Shared string data from the CDS archive is being ignored. " 656 "The current CompressedOops/CompressedClassPointers encoding differs from " 657 "that archived due to heap size change. The archive was dumped using max heap " 658 "size " UINTX_FORMAT "M.", max_heap_size()/M); 659 } 660 } else { 661 string_ranges = new MemRegion[MetaspaceShared::max_strings]; 662 struct FileMapInfo::FileMapHeader::space_info* si; 663 664 for (int i = MetaspaceShared::first_string; 665 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) { 666 si = &_header->_space[i]; 667 size_t used = si->_used; 668 if (used > 0) { 669 size_t size = used; 670 char* requested_addr = (char*)((void*)oopDesc::decode_heap_oop_not_null( 671 (narrowOop)si->_addr._offset)); 672 string_ranges[num_ranges] = MemRegion((HeapWord*)requested_addr, size / HeapWordSize); 673 num_ranges ++; 674 } 675 } 676 677 if (num_ranges == 0) { 678 StringTable::ignore_shared_strings(true); 679 return true; // no shared string data 680 } 681 682 // Check that ranges are within the java heap 683 if (!G1CollectedHeap::heap()->check_archive_addresses(string_ranges, num_ranges)) { 684 fail_continue("Unable to allocate shared string space: range is not " 685 "within java heap."); 686 return false; 687 } 688 689 // allocate from java heap 690 if (!G1CollectedHeap::heap()->alloc_archive_regions(string_ranges, num_ranges)) { 691 fail_continue("Unable to allocate shared string space: range is " 692 "already in use."); 693 return false; 694 } 695 696 // Map the string data. No need to call MemTracker::record_virtual_memory_type() 697 // for mapped string regions as they are part of the reserved java heap, which 698 // is already recorded. 699 for (int i = 0; i < num_ranges; i++) { 700 si = &_header->_space[MetaspaceShared::first_string + i]; 701 char* addr = (char*)string_ranges[i].start(); 702 char* base = os::map_memory(_fd, _full_path, si->_file_offset, 703 addr, string_ranges[i].byte_size(), si->_read_only, 704 si->_allow_exec); 705 if (base == NULL || base != addr) { 706 // dealloc the string regions from java heap 707 dealloc_string_regions(); 708 fail_continue("Unable to map shared string space at required address."); 709 return false; 710 } 711 } 712 713 if (!verify_string_regions()) { 714 // dealloc the string regions from java heap 715 dealloc_string_regions(); 716 fail_continue("Shared string regions are corrupt"); 717 return false; 718 } 719 720 // the shared string data is mapped successfully 721 return true; 722 } 723 } else { 724 if (PrintSharedSpaces && _header->_space[MetaspaceShared::first_string]._used > 0) { 725 tty->print_cr("Shared string data from the CDS archive is being ignored. UseG1GC, " 726 "UseCompressedOops and UseCompressedClassPointers are required."); 727 } 728 } 729 730 // if we get here, the shared string data is not mapped 731 assert(string_ranges == NULL && num_ranges == 0, "sanity"); 732 StringTable::ignore_shared_strings(true); 733 #endif 734 return true; 735 } 736 737 bool FileMapInfo::verify_string_regions() { 738 for (int i = MetaspaceShared::first_string; 739 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) { 740 if (!verify_region_checksum(i)) { 741 return false; 742 } 743 } 744 return true; 745 } 746 747 void FileMapInfo::fixup_string_regions() { 748 #if INCLUDE_ALL_GCS 749 // If any string regions were found, call the fill routine to make them parseable. 750 // Note that string_ranges may be non-NULL even if no ranges were found. 751 if (num_ranges != 0) { 752 assert(string_ranges != NULL, "Null string_ranges array with non-zero count"); 753 G1CollectedHeap::heap()->fill_archive_regions(string_ranges, num_ranges); 754 } 755 #endif 756 } 757 758 bool FileMapInfo::verify_region_checksum(int i) { 759 if (!VerifySharedSpaces) { 760 return true; 761 } 762 763 size_t sz = _header->_space[i]._used; 764 765 if (sz == 0) { 766 return true; // no data 767 } 768 if (MetaspaceShared::is_string_region(i) && StringTable::shared_string_ignored()) { 769 return true; // shared string data are not mapped 770 } 771 const char* buf = _header->region_addr(i); 772 int crc = ClassLoader::crc32(0, buf, (jint)sz); 773 if (crc != _header->_space[i]._crc) { 774 fail_continue("Checksum verification failed."); 775 return false; 776 } 777 return true; 778 } 779 780 // Unmap a memory region in the address space. 781 782 void FileMapInfo::unmap_region(int i) { 783 assert(!MetaspaceShared::is_string_region(i), "sanity"); 784 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i]; 785 size_t used = si->_used; 786 size_t size = align_size_up(used, os::vm_allocation_granularity()); 787 788 if (used == 0) { 789 return; 790 } 791 792 char* addr = _header->region_addr(i); 793 if (!os::unmap_memory(addr, size)) { 794 fail_stop("Unable to unmap shared space."); 795 } 796 } 797 798 // dealloc the archived string region from java heap 799 void FileMapInfo::dealloc_string_regions() { 800 #if INCLUDE_ALL_GCS 801 if (num_ranges > 0) { 802 assert(string_ranges != NULL, "Null string_ranges array with non-zero count"); 803 G1CollectedHeap::heap()->dealloc_archive_regions(string_ranges, num_ranges); 804 } 805 #endif 806 } 807 808 void FileMapInfo::assert_mark(bool check) { 809 if (!check) { 810 fail_stop("Mark mismatch while restoring from shared file."); 811 } 812 } 813 814 815 FileMapInfo* FileMapInfo::_current_info = NULL; 816 SharedClassPathEntry* FileMapInfo::_classpath_entry_table = NULL; 817 int FileMapInfo::_classpath_entry_table_size = 0; 818 size_t FileMapInfo::_classpath_entry_size = 0x1234baad; 819 bool FileMapInfo::_validating_classpath_entry_table = false; 820 821 // Open the shared archive file, read and validate the header 822 // information (version, boot classpath, etc.). If initialization 823 // fails, shared spaces are disabled and the file is closed. [See 824 // fail_continue.] 825 // 826 // Validation of the archive is done in two steps: 827 // 828 // [1] validate_header() - done here. This checks the header, including _paths_misc_info. 829 // [2] validate_classpath_entry_table - this is done later, because the table is in the RW 830 // region of the archive, which is not mapped yet. 831 bool FileMapInfo::initialize() { 832 assert(UseSharedSpaces, "UseSharedSpaces expected."); 833 834 if (!open_for_read()) { 835 return false; 836 } 837 838 init_from_file(_fd); 839 if (!validate_header()) { 840 return false; 841 } 842 843 SharedReadOnlySize = _header->_space[0]._capacity; 844 SharedReadWriteSize = _header->_space[1]._capacity; 845 SharedMiscDataSize = _header->_space[2]._capacity; 846 SharedMiscCodeSize = _header->_space[3]._capacity; 847 return true; 848 } 849 850 char* FileMapInfo::FileMapHeader::region_addr(int idx) { 851 if (MetaspaceShared::is_string_region(idx)) { 852 return (char*)((void*)oopDesc::decode_heap_oop_not_null( 853 (narrowOop)_space[idx]._addr._offset)); 854 } else { 855 return _space[idx]._addr._base; 856 } 857 } 858 859 int FileMapInfo::FileMapHeader::compute_crc() { 860 char* header = data(); 861 // start computing from the field after _crc 862 char* buf = (char*)&_crc + sizeof(int); 863 size_t sz = data_size() - (buf - header); 864 int crc = ClassLoader::crc32(0, buf, (jint)sz); 865 return crc; 866 } 867 868 bool FileMapInfo::FileMapHeader::validate() { 869 if (VerifySharedSpaces && compute_crc() != _crc) { 870 fail_continue("Header checksum verification failed."); 871 return false; 872 } 873 874 if (_version != current_version()) { 875 FileMapInfo::fail_continue("The shared archive file is the wrong version."); 876 return false; 877 } 878 if (_magic != (int)0xf00baba2) { 879 FileMapInfo::fail_continue("The shared archive file has a bad magic number."); 880 return false; 881 } 882 char header_version[JVM_IDENT_MAX]; 883 get_header_version(header_version); 884 if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) { 885 log_info(classpath)("expected: %s", header_version); 886 log_info(classpath)("actual: %s", _jvm_ident); 887 FileMapInfo::fail_continue("The shared archive file was created by a different" 888 " version or build of HotSpot"); 889 return false; 890 } 891 if (_obj_alignment != ObjectAlignmentInBytes) { 892 FileMapInfo::fail_continue("The shared archive file's ObjectAlignmentInBytes of %d" 893 " does not equal the current ObjectAlignmentInBytes of " INTX_FORMAT ".", 894 _obj_alignment, ObjectAlignmentInBytes); 895 return false; 896 } 897 if (_compact_strings != CompactStrings) { 898 FileMapInfo::fail_continue("The shared archive file's CompactStrings setting (%s)" 899 " does not equal the current CompactStrings setting (%s).", 900 _compact_strings ? "enabled" : "disabled", 901 CompactStrings ? "enabled" : "disabled"); 902 return false; 903 } 904 905 return true; 906 } 907 908 bool FileMapInfo::validate_header() { 909 bool status = _header->validate(); 910 911 if (status) { 912 if (!ClassLoader::check_shared_paths_misc_info(_paths_misc_info, _header->_paths_misc_info_size)) { 913 if (!PrintSharedArchiveAndExit) { 914 fail_continue("shared class paths mismatch (hint: enable -Xlog:classpath=info to diagnose the failure)"); 915 status = false; 916 } 917 } 918 } 919 920 if (_paths_misc_info != NULL) { 921 FREE_C_HEAP_ARRAY(char, _paths_misc_info); 922 _paths_misc_info = NULL; 923 } 924 return status; 925 } 926 927 // The following method is provided to see whether a given pointer 928 // falls in the mapped shared space. 929 // Param: 930 // p, The given pointer 931 // Return: 932 // True if the p is within the mapped shared space, otherwise, false. 933 bool FileMapInfo::is_in_shared_space(const void* p) { 934 for (int i = 0; i < MetaspaceShared::n_regions; i++) { 935 char *base; 936 if (MetaspaceShared::is_string_region(i) && _header->_space[i]._used == 0) { 937 continue; 938 } 939 base = _header->region_addr(i); 940 if (p >= base && p < base + _header->_space[i]._used) { 941 return true; 942 } 943 } 944 945 return false; 946 } 947 948 void FileMapInfo::print_shared_spaces() { 949 tty->print_cr("Shared Spaces:"); 950 for (int i = 0; i < MetaspaceShared::n_regions; i++) { 951 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i]; 952 char *base = _header->region_addr(i); 953 tty->print(" %s " INTPTR_FORMAT "-" INTPTR_FORMAT, 954 shared_region_name[i], 955 p2i(base), p2i(base + si->_used)); 956 } 957 } 958 959 // Unmap mapped regions of shared space. 960 void FileMapInfo::stop_sharing_and_unmap(const char* msg) { 961 FileMapInfo *map_info = FileMapInfo::current_info(); 962 if (map_info) { 963 map_info->fail_continue("%s", msg); 964 for (int i = 0; i < MetaspaceShared::num_non_strings; i++) { 965 char *addr = map_info->_header->region_addr(i); 966 if (addr != NULL && !MetaspaceShared::is_string_region(i)) { 967 map_info->unmap_region(i); 968 map_info->_header->_space[i]._addr._base = NULL; 969 } 970 } 971 // Dealloc the string regions only without unmapping. The string regions are part 972 // of the java heap. Unmapping of the heap regions are managed by GC. 973 map_info->dealloc_string_regions(); 974 } else if (DumpSharedSpaces) { 975 fail_stop("%s", msg); 976 } 977 } --- EOF ---