1 /*
   2  * Copyright (c) 2003, 2025, 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 "cds/aotClassLocation.hpp"
  26 #include "cds/aotLogging.hpp"
  27 #include "cds/aotMappedHeapLoader.hpp"
  28 #include "cds/aotMappedHeapWriter.hpp"
  29 #include "cds/aotMetaspace.hpp"
  30 #include "cds/archiveBuilder.hpp"
  31 #include "cds/archiveUtils.inline.hpp"
  32 #include "cds/cds_globals.hpp"
  33 #include "cds/cdsConfig.hpp"
  34 #include "cds/dynamicArchive.hpp"
  35 #include "cds/filemap.hpp"
  36 #include "cds/heapShared.inline.hpp"
  37 #include "classfile/altHashing.hpp"
  38 #include "classfile/classFileStream.hpp"
  39 #include "classfile/classLoader.hpp"
  40 #include "classfile/classLoader.inline.hpp"
  41 #include "classfile/classLoaderData.inline.hpp"
  42 #include "classfile/symbolTable.hpp"
  43 #include "classfile/systemDictionaryShared.hpp"
  44 #include "classfile/vmClasses.hpp"
  45 #include "classfile/vmSymbols.hpp"
  46 #include "compiler/compilerDefinitions.inline.hpp"
  47 #include "jvm.h"
  48 #include "logging/log.hpp"
  49 #include "logging/logMessage.hpp"
  50 #include "logging/logStream.hpp"
  51 #include "memory/iterator.inline.hpp"
  52 #include "memory/metadataFactory.hpp"
  53 #include "memory/metaspaceClosure.hpp"
  54 #include "memory/oopFactory.hpp"
  55 #include "memory/universe.hpp"
  56 #include "nmt/memTracker.hpp"
  57 #include "oops/access.hpp"
  58 #include "oops/compressedKlass.hpp"
  59 #include "oops/compressedOops.hpp"
  60 #include "oops/compressedOops.inline.hpp"
  61 #include "oops/objArrayOop.hpp"
  62 #include "oops/oop.inline.hpp"
  63 #include "oops/trainingData.hpp"
  64 #include "oops/typeArrayKlass.hpp"
  65 #include "prims/jvmtiExport.hpp"
  66 #include "runtime/arguments.hpp"
  67 #include "runtime/globals_extension.hpp"
  68 #include "runtime/java.hpp"
  69 #include "runtime/javaCalls.hpp"
  70 #include "runtime/mutexLocker.hpp"
  71 #include "runtime/os.hpp"
  72 #include "runtime/vm_version.hpp"
  73 #include "utilities/align.hpp"
  74 #include "utilities/bitMap.inline.hpp"
  75 #include "utilities/classpathStream.hpp"
  76 #include "utilities/defaultStream.hpp"
  77 #include "utilities/ostream.hpp"
  78 #if INCLUDE_G1GC
  79 #include "gc/g1/g1CollectedHeap.hpp"
  80 #include "gc/g1/g1HeapRegion.hpp"
  81 #endif
  82 
  83 #include <errno.h>
  84 #include <sys/stat.h>
  85 
  86 #ifndef O_BINARY       // if defined (Win32) use binary files.
  87 #define O_BINARY 0     // otherwise do nothing.
  88 #endif
  89 
  90 // Fill in the fileMapInfo structure with data about this VM instance.
  91 
  92 // This method copies the vm version info into header_version.  If the version is too
  93 // long then a truncated version, which has a hash code appended to it, is copied.
  94 //
  95 // Using a template enables this method to verify that header_version is an array of
  96 // length JVM_IDENT_MAX.  This ensures that the code that writes to the CDS file and
  97 // the code that reads the CDS file will both use the same size buffer.  Hence, will
  98 // use identical truncation.  This is necessary for matching of truncated versions.
  99 template <int N> static void get_header_version(char (&header_version) [N]) {
 100   assert(N == JVM_IDENT_MAX, "Bad header_version size");
 101 
 102   const char *vm_version = VM_Version::internal_vm_info_string();
 103   const int version_len = (int)strlen(vm_version);
 104 
 105   memset(header_version, 0, JVM_IDENT_MAX);
 106 
 107   if (version_len < (JVM_IDENT_MAX-1)) {
 108     strcpy(header_version, vm_version);
 109 
 110   } else {
 111     // Get the hash value.  Use a static seed because the hash needs to return the same
 112     // value over multiple jvm invocations.
 113     uint32_t hash = AltHashing::halfsiphash_32(8191, (const uint8_t*)vm_version, version_len);
 114 
 115     // Truncate the ident, saving room for the 8 hex character hash value.
 116     strncpy(header_version, vm_version, JVM_IDENT_MAX-9);
 117 
 118     // Append the hash code as eight hex digits.
 119     os::snprintf_checked(&header_version[JVM_IDENT_MAX-9], 9, "%08x", hash);
 120   }
 121 
 122   assert(header_version[JVM_IDENT_MAX-1] == 0, "must be");
 123 }
 124 
 125 FileMapInfo::FileMapInfo(const char* full_path, bool is_static) :
 126   _is_static(is_static), _file_open(false), _is_mapped(false), _fd(-1), _file_offset(0),
 127   _full_path(full_path), _base_archive_name(nullptr), _header(nullptr) {
 128   if (_is_static) {
 129     assert(_current_info == nullptr, "must be singleton"); // not thread safe
 130     _current_info = this;
 131   } else {
 132     assert(_dynamic_archive_info == nullptr, "must be singleton"); // not thread safe
 133     _dynamic_archive_info = this;
 134   }
 135 }
 136 
 137 FileMapInfo::~FileMapInfo() {
 138   if (_is_static) {
 139     assert(_current_info == this, "must be singleton"); // not thread safe
 140     _current_info = nullptr;
 141   } else {
 142     assert(_dynamic_archive_info == this, "must be singleton"); // not thread safe
 143     _dynamic_archive_info = nullptr;
 144   }
 145 
 146   if (_header != nullptr) {
 147     os::free(_header);
 148   }
 149 
 150   if (_file_open) {
 151     ::close(_fd);
 152   }
 153 }
 154 
 155 void FileMapInfo::free_current_info() {
 156   assert(CDSConfig::is_dumping_final_static_archive(), "only supported in this mode");
 157   assert(_current_info != nullptr, "sanity");
 158   delete _current_info;
 159   assert(_current_info == nullptr, "sanity"); // Side effect expected from the above "delete" operator.
 160 }
 161 
 162 void FileMapInfo::populate_header(size_t core_region_alignment) {
 163   assert(_header == nullptr, "Sanity check");
 164   size_t c_header_size;
 165   size_t header_size;
 166   size_t base_archive_name_size = 0;
 167   size_t base_archive_name_offset = 0;
 168   if (is_static()) {
 169     c_header_size = sizeof(FileMapHeader);
 170     header_size = c_header_size;
 171   } else {
 172     // dynamic header including base archive name for non-default base archive
 173     c_header_size = sizeof(DynamicArchiveHeader);
 174     header_size = c_header_size;
 175 
 176     const char* default_base_archive_name = CDSConfig::default_archive_path();
 177     const char* current_base_archive_name = CDSConfig::input_static_archive_path();
 178     if (!os::same_files(current_base_archive_name, default_base_archive_name)) {
 179       base_archive_name_size = strlen(current_base_archive_name) + 1;
 180       header_size += base_archive_name_size;
 181       base_archive_name_offset = c_header_size;
 182     }
 183   }
 184   _header = (FileMapHeader*)os::malloc(header_size, mtInternal);
 185   memset((void*)_header, 0, header_size);
 186   _header->populate(this,
 187                     core_region_alignment,
 188                     header_size,
 189                     base_archive_name_size,
 190                     base_archive_name_offset);
 191 }
 192 
 193 void FileMapHeader::populate(FileMapInfo *info, size_t core_region_alignment,
 194                              size_t header_size, size_t base_archive_name_size,
 195                              size_t base_archive_name_offset) {
 196   // 1. We require _generic_header._magic to be at the beginning of the file
 197   // 2. FileMapHeader also assumes that _generic_header is at the beginning of the file
 198   assert(offset_of(FileMapHeader, _generic_header) == 0, "must be");
 199   set_header_size((unsigned int)header_size);
 200   set_base_archive_name_offset((unsigned int)base_archive_name_offset);
 201   set_base_archive_name_size((unsigned int)base_archive_name_size);
 202   if (CDSConfig::is_dumping_dynamic_archive()) {
 203     set_magic(CDS_DYNAMIC_ARCHIVE_MAGIC);
 204   } else if (CDSConfig::is_dumping_preimage_static_archive()) {
 205     set_magic(CDS_PREIMAGE_ARCHIVE_MAGIC);
 206   } else {
 207     set_magic(CDS_ARCHIVE_MAGIC);
 208   }
 209   set_version(CURRENT_CDS_ARCHIVE_VERSION);
 210 
 211   if (!info->is_static() && base_archive_name_size != 0) {
 212     // copy base archive name
 213     copy_base_archive_name(CDSConfig::input_static_archive_path());
 214   }
 215   _core_region_alignment = core_region_alignment;
 216   _obj_alignment = ObjectAlignmentInBytes;
 217   _compact_strings = CompactStrings;
 218   _compact_headers = UseCompactObjectHeaders;
 219 #if INCLUDE_CDS_JAVA_HEAP
 220   if (CDSConfig::is_dumping_heap()) {
 221     _object_streaming_mode = HeapShared::is_writing_streaming_mode();
 222     _narrow_oop_mode = AOTMappedHeapWriter::narrow_oop_mode();
 223     _narrow_oop_base = AOTMappedHeapWriter::narrow_oop_base();
 224     _narrow_oop_shift = AOTMappedHeapWriter::narrow_oop_shift();
 225   }
 226 #endif
 227   _compressed_oops = UseCompressedOops;
 228   _compressed_class_ptrs = UseCompressedClassPointers;
 229   if (UseCompressedClassPointers) {
 230 #ifdef _LP64
 231     _narrow_klass_pointer_bits = CompressedKlassPointers::narrow_klass_pointer_bits();
 232     _narrow_klass_shift = ArchiveBuilder::precomputed_narrow_klass_shift();
 233 #endif
 234   } else {
 235     _narrow_klass_pointer_bits = _narrow_klass_shift = -1;
 236   }
 237   // Which JIT compier is used
 238   _compiler_type = (u1)CompilerConfig::compiler_type();
 239   _type_profile_level = TypeProfileLevel;
 240   _type_profile_args_limit = TypeProfileArgsLimit;
 241   _type_profile_parms_limit = TypeProfileParmsLimit;
 242   _type_profile_width = TypeProfileWidth;
 243   _bci_profile_width = BciProfileWidth;
 244   _profile_traps = ProfileTraps;
 245   _type_profile_casts = TypeProfileCasts;
 246   _spec_trap_limit_extra_entries = SpecTrapLimitExtraEntries;
 247   _max_heap_size = MaxHeapSize;
 248   _use_optimized_module_handling = CDSConfig::is_using_optimized_module_handling();
 249   _has_aot_linked_classes = CDSConfig::is_dumping_aot_linked_classes();
 250   _has_full_module_graph = CDSConfig::is_dumping_full_module_graph();
 251 
 252   // The following fields are for sanity checks for whether this archive
 253   // will function correctly with this JVM and the bootclasspath it's
 254   // invoked with.
 255 
 256   // JVM version string ... changes on each build.
 257   get_header_version(_jvm_ident);
 258 
 259   _verify_local = BytecodeVerificationLocal;
 260   _verify_remote = BytecodeVerificationRemote;
 261   _has_platform_or_app_classes = AOTClassLocationConfig::dumptime()->has_platform_or_app_classes();
 262   _requested_base_address = (char*)SharedBaseAddress;
 263   _mapped_base_address = (char*)SharedBaseAddress;
 264 }
 265 
 266 void FileMapHeader::copy_base_archive_name(const char* archive) {
 267   assert(base_archive_name_size() != 0, "_base_archive_name_size not set");
 268   assert(base_archive_name_offset() != 0, "_base_archive_name_offset not set");
 269   assert(header_size() > sizeof(*this), "_base_archive_name_size not included in header size?");
 270   memcpy((char*)this + base_archive_name_offset(), archive, base_archive_name_size());
 271 }
 272 
 273 void FileMapHeader::print(outputStream* st) {
 274   ResourceMark rm;
 275 
 276   st->print_cr("- magic:                          0x%08x", magic());
 277   st->print_cr("- crc:                            0x%08x", crc());
 278   st->print_cr("- version:                        0x%x", version());
 279   st->print_cr("- header_size:                    " UINT32_FORMAT, header_size());
 280   st->print_cr("- base_archive_name_offset:       " UINT32_FORMAT, base_archive_name_offset());
 281   st->print_cr("- base_archive_name_size:         " UINT32_FORMAT, base_archive_name_size());
 282 
 283   for (int i = 0; i < NUM_CDS_REGIONS; i++) {
 284     FileMapRegion* r = region_at(i);
 285     r->print(st, i);
 286   }
 287   st->print_cr("============ end regions ======== ");
 288 
 289   st->print_cr("- core_region_alignment:                    %zu", _core_region_alignment);
 290   st->print_cr("- obj_alignment:                            %d", _obj_alignment);
 291   st->print_cr("- narrow_oop_base:                          " INTPTR_FORMAT, p2i(_narrow_oop_base));
 292   st->print_cr("- narrow_oop_shift                          %d", _narrow_oop_shift);
 293   st->print_cr("- compact_strings:                          %d", _compact_strings);
 294   st->print_cr("- compact_headers:                          %d", _compact_headers);
 295   st->print_cr("- max_heap_size:                            %zu", _max_heap_size);
 296   st->print_cr("- narrow_oop_mode:                          %d", _narrow_oop_mode);
 297   st->print_cr("- compressed_oops:                          %d", _compressed_oops);
 298   st->print_cr("- compressed_class_ptrs:                    %d", _compressed_class_ptrs);
 299   st->print_cr("- narrow_klass_pointer_bits:                %d", _narrow_klass_pointer_bits);
 300   st->print_cr("- narrow_klass_shift:                       %d", _narrow_klass_shift);
 301   st->print_cr("- cloned_vtables_offset:                    0x%zx", _cloned_vtables_offset);
 302   st->print_cr("- early_serialized_data_offset:             0x%zx", _early_serialized_data_offset);
 303   st->print_cr("- serialized_data_offset:                   0x%zx", _serialized_data_offset);
 304   st->print_cr("- jvm_ident:                                %s", _jvm_ident);
 305   st->print_cr("- class_location_config_offset:             0x%zx", _class_location_config_offset);
 306   st->print_cr("- verify_local:                             %d", _verify_local);
 307   st->print_cr("- verify_remote:                            %d", _verify_remote);
 308   st->print_cr("- has_platform_or_app_classes:              %d", _has_platform_or_app_classes);
 309   st->print_cr("- requested_base_address:                   " INTPTR_FORMAT, p2i(_requested_base_address));
 310   st->print_cr("- mapped_base_address:                      " INTPTR_FORMAT, p2i(_mapped_base_address));
 311 
 312   st->print_cr("- object_streaming_mode:                    %d", _object_streaming_mode);
 313   st->print_cr("- mapped_heap_header");
 314   st->print_cr("  - root_segments");
 315   st->print_cr("    - roots_count:                          %d", _mapped_heap_header.root_segments().roots_count());
 316   st->print_cr("    - base_offset:                          0x%zx", _mapped_heap_header.root_segments().base_offset());
 317   st->print_cr("    - count:                                %zu", _mapped_heap_header.root_segments().count());
 318   st->print_cr("    - max_size_elems:                       %d", _mapped_heap_header.root_segments().max_size_in_elems());
 319   st->print_cr("    - max_size_bytes:                       %zu", _mapped_heap_header.root_segments().max_size_in_bytes());
 320   st->print_cr("  - oopmap_start_pos:                       %zu", _mapped_heap_header.oopmap_start_pos());
 321   st->print_cr("  - oopmap_ptrmap_pos:                      %zu", _mapped_heap_header.ptrmap_start_pos());
 322   st->print_cr("- streamed_heap_header");
 323   st->print_cr("  - forwarding_offset:                      %zu", _streamed_heap_header.forwarding_offset());
 324   st->print_cr("  - roots_offset:                           %zu", _streamed_heap_header.roots_offset());
 325   st->print_cr("  - num_roots:                              %zu", _streamed_heap_header.num_roots());
 326   st->print_cr("  - root_highest_object_index_table_offset: %zu", _streamed_heap_header.root_highest_object_index_table_offset());
 327   st->print_cr("  - num_archived_objects:                   %zu", _streamed_heap_header.num_archived_objects());
 328 
 329   st->print_cr("- _rw_ptrmap_start_pos:                     %zu", _rw_ptrmap_start_pos);
 330   st->print_cr("- _ro_ptrmap_start_pos:                     %zu", _ro_ptrmap_start_pos);
 331   st->print_cr("- use_optimized_module_handling:            %d", _use_optimized_module_handling);
 332   st->print_cr("- has_full_module_graph                     %d", _has_full_module_graph);
 333   st->print_cr("- has_aot_linked_classes                    %d", _has_aot_linked_classes);
 334 }
 335 
 336 bool FileMapInfo::validate_class_location() {
 337   assert(CDSConfig::is_using_archive(), "runtime only");
 338 
 339   AOTClassLocationConfig* config = header()->class_location_config();
 340   bool has_extra_module_paths = false;
 341   if (!config->validate(full_path(), header()->has_aot_linked_classes(), &has_extra_module_paths)) {
 342     if (PrintSharedArchiveAndExit) {
 343       AOTMetaspace::set_archive_loading_failed();
 344       return true;
 345     } else {
 346       return false;
 347     }
 348   }
 349 
 350   if (header()->has_full_module_graph() && has_extra_module_paths) {
 351     CDSConfig::stop_using_optimized_module_handling();
 352     AOTMetaspace::report_loading_error("optimized module handling: disabled because extra module path(s) are specified");
 353   }
 354 
 355   if (CDSConfig::is_dumping_dynamic_archive()) {
 356     // Only support dynamic dumping with the usage of the default CDS archive
 357     // or a simple base archive.
 358     // If the base layer archive contains additional path component besides
 359     // the runtime image and the -cp, dynamic dumping is disabled.
 360     if (config->num_boot_classpaths() > 0) {
 361       CDSConfig::disable_dumping_dynamic_archive();
 362       aot_log_warning(aot)(
 363         "Dynamic archiving is disabled because base layer archive has appended boot classpath");
 364     }
 365     if (config->num_module_paths() > 0) {
 366       if (has_extra_module_paths) {
 367         CDSConfig::disable_dumping_dynamic_archive();
 368         aot_log_warning(aot)(
 369           "Dynamic archiving is disabled because base layer archive has a different module path");
 370       }
 371     }
 372   }
 373 
 374 #if INCLUDE_JVMTI
 375   if (_classpath_entries_for_jvmti != nullptr) {
 376     os::free(_classpath_entries_for_jvmti);
 377   }
 378   size_t sz = sizeof(ClassPathEntry*) * AOTClassLocationConfig::runtime()->length();
 379   _classpath_entries_for_jvmti = (ClassPathEntry**)os::malloc(sz, mtClass);
 380   memset((void*)_classpath_entries_for_jvmti, 0, sz);
 381 #endif
 382 
 383   return true;
 384 }
 385 
 386 // A utility class for reading/validating the GenericCDSFileMapHeader portion of
 387 // a CDS archive's header. The file header of all CDS archives with versions from
 388 // CDS_GENERIC_HEADER_SUPPORTED_MIN_VERSION (12) are guaranteed to always start
 389 // with GenericCDSFileMapHeader. This makes it possible to read important information
 390 // from a CDS archive created by a different version of HotSpot, so that we can
 391 // automatically regenerate the archive as necessary (JDK-8261455).
 392 class FileHeaderHelper {
 393   int _fd;
 394   bool _is_valid;
 395   bool _is_static;
 396   GenericCDSFileMapHeader* _header;
 397   const char* _archive_name;
 398   const char* _base_archive_name;
 399 
 400 public:
 401   FileHeaderHelper(const char* archive_name, bool is_static) {
 402     _fd = -1;
 403     _is_valid = false;
 404     _header = nullptr;
 405     _base_archive_name = nullptr;
 406     _archive_name = archive_name;
 407     _is_static = is_static;
 408   }
 409 
 410   ~FileHeaderHelper() {
 411     if (_header != nullptr) {
 412       FREE_C_HEAP_ARRAY(char, _header);
 413     }
 414     if (_fd != -1) {
 415       ::close(_fd);
 416     }
 417   }
 418 
 419   bool initialize() {
 420     assert(_archive_name != nullptr, "Archive name is null");
 421     _fd = os::open(_archive_name, O_RDONLY | O_BINARY, 0);
 422     if (_fd < 0) {
 423       AOTMetaspace::report_loading_error("Specified %s not found (%s)", CDSConfig::type_of_archive_being_loaded(), _archive_name);
 424       return false;
 425     }
 426     return initialize(_fd);
 427   }
 428 
 429   // for an already opened file, do not set _fd
 430   bool initialize(int fd) {
 431     assert(_archive_name != nullptr, "Archive name is null");
 432     assert(fd != -1, "Archive must be opened already");
 433     // First read the generic header so we know the exact size of the actual header.
 434     const char* file_type = CDSConfig::type_of_archive_being_loaded();
 435     GenericCDSFileMapHeader gen_header;
 436     size_t size = sizeof(GenericCDSFileMapHeader);
 437     os::lseek(fd, 0, SEEK_SET);
 438     size_t n = ::read(fd, (void*)&gen_header, (unsigned int)size);
 439     if (n != size) {
 440       aot_log_warning(aot)("Unable to read generic CDS file map header from %s", file_type);
 441       return false;
 442     }
 443 
 444     if (gen_header._magic != CDS_ARCHIVE_MAGIC &&
 445         gen_header._magic != CDS_DYNAMIC_ARCHIVE_MAGIC &&
 446         gen_header._magic != CDS_PREIMAGE_ARCHIVE_MAGIC) {
 447       aot_log_warning(aot)("The %s has a bad magic number: %#x", file_type, gen_header._magic);
 448       return false;
 449     }
 450 
 451     if (gen_header._version < CDS_GENERIC_HEADER_SUPPORTED_MIN_VERSION) {
 452       aot_log_warning(aot)("Cannot handle %s version 0x%x. Must be at least 0x%x.",
 453                        file_type, gen_header._version, CDS_GENERIC_HEADER_SUPPORTED_MIN_VERSION);
 454       return false;
 455     }
 456 
 457     if (gen_header._version !=  CURRENT_CDS_ARCHIVE_VERSION) {
 458       aot_log_warning(aot)("The %s version 0x%x does not match the required version 0x%x.",
 459                        file_type, gen_header._version, CURRENT_CDS_ARCHIVE_VERSION);
 460     }
 461 
 462     size_t filelen = os::lseek(fd, 0, SEEK_END);
 463     if (gen_header._header_size >= filelen) {
 464       aot_log_warning(aot)("Archive file header larger than archive file");
 465       return false;
 466     }
 467 
 468     // Read the actual header and perform more checks
 469     size = gen_header._header_size;
 470     _header = (GenericCDSFileMapHeader*)NEW_C_HEAP_ARRAY(char, size, mtInternal);
 471     os::lseek(fd, 0, SEEK_SET);
 472     n = ::read(fd, (void*)_header, (unsigned int)size);
 473     if (n != size) {
 474       aot_log_warning(aot)("Unable to read file map header from %s", file_type);
 475       return false;
 476     }
 477 
 478     if (!check_header_crc()) {
 479       return false;
 480     }
 481 
 482     if (!check_and_init_base_archive_name()) {
 483       return false;
 484     }
 485 
 486     // All fields in the GenericCDSFileMapHeader has been validated.
 487     _is_valid = true;
 488     return true;
 489   }
 490 
 491   GenericCDSFileMapHeader* get_generic_file_header() {
 492     assert(_header != nullptr && _is_valid, "must be a valid archive file");
 493     return _header;
 494   }
 495 
 496   const char* base_archive_name() {
 497     assert(_header != nullptr && _is_valid, "must be a valid archive file");
 498     return _base_archive_name;
 499   }
 500 
 501   bool is_static_archive() const {
 502     return _header->_magic == CDS_ARCHIVE_MAGIC;
 503   }
 504 
 505   bool is_dynamic_archive() const {
 506     return _header->_magic == CDS_DYNAMIC_ARCHIVE_MAGIC;
 507   }
 508 
 509   bool is_preimage_static_archive() const {
 510     return _header->_magic == CDS_PREIMAGE_ARCHIVE_MAGIC;
 511   }
 512 
 513  private:
 514   bool check_header_crc() const {
 515     if (VerifySharedSpaces) {
 516       FileMapHeader* header = (FileMapHeader*)_header;
 517       int actual_crc = header->compute_crc();
 518       if (actual_crc != header->crc()) {
 519         aot_log_info(aot)("_crc expected: %d", header->crc());
 520         aot_log_info(aot)("       actual: %d", actual_crc);
 521         aot_log_warning(aot)("Header checksum verification failed.");
 522         return false;
 523       }
 524     }
 525     return true;
 526   }
 527 
 528   bool check_and_init_base_archive_name() {
 529     unsigned int name_offset = _header->_base_archive_name_offset;
 530     unsigned int name_size   = _header->_base_archive_name_size;
 531     unsigned int header_size = _header->_header_size;
 532 
 533     if (name_offset + name_size < name_offset) {
 534       aot_log_warning(aot)("base_archive_name offset/size overflow: " UINT32_FORMAT "/" UINT32_FORMAT,
 535                                  name_offset, name_size);
 536       return false;
 537     }
 538 
 539     if (is_static_archive() || is_preimage_static_archive()) {
 540       if (name_offset != 0) {
 541         aot_log_warning(aot)("static shared archive must have zero _base_archive_name_offset");
 542         return false;
 543       }
 544       if (name_size != 0) {
 545         aot_log_warning(aot)("static shared archive must have zero _base_archive_name_size");
 546         return false;
 547       }
 548     } else {
 549       assert(is_dynamic_archive(), "must be");
 550       if ((name_size == 0 && name_offset != 0) ||
 551           (name_size != 0 && name_offset == 0)) {
 552         // If either is zero, both must be zero. This indicates that we are using the default base archive.
 553         aot_log_warning(aot)("Invalid base_archive_name offset/size: " UINT32_FORMAT "/" UINT32_FORMAT,
 554                                    name_offset, name_size);
 555         return false;
 556       }
 557       if (name_size > 0) {
 558         if (name_offset + name_size > header_size) {
 559           aot_log_warning(aot)("Invalid base_archive_name offset/size (out of range): "
 560                                      UINT32_FORMAT " + " UINT32_FORMAT " > " UINT32_FORMAT ,
 561                                      name_offset, name_size, header_size);
 562           return false;
 563         }
 564         const char* name = ((const char*)_header) + _header->_base_archive_name_offset;
 565         if (name[name_size - 1] != '\0' || strlen(name) != name_size - 1) {
 566           aot_log_warning(aot)("Base archive name is damaged");
 567           return false;
 568         }
 569         if (!os::file_exists(name)) {
 570           aot_log_warning(aot)("Base archive %s does not exist", name);
 571           return false;
 572         }
 573         _base_archive_name = name;
 574       }
 575     }
 576 
 577     return true;
 578   }
 579 };
 580 
 581 // Return value:
 582 // false:
 583 //      <archive_name> is not a valid archive. *base_archive_name is set to null.
 584 // true && (*base_archive_name) == nullptr:
 585 //      <archive_name> is a valid static archive.
 586 // true && (*base_archive_name) != nullptr:
 587 //      <archive_name> is a valid dynamic archive.
 588 bool FileMapInfo::get_base_archive_name_from_header(const char* archive_name,
 589                                                     const char** base_archive_name) {
 590   FileHeaderHelper file_helper(archive_name, false);
 591   *base_archive_name = nullptr;
 592 
 593   if (!file_helper.initialize()) {
 594     return false;
 595   }
 596   GenericCDSFileMapHeader* header = file_helper.get_generic_file_header();
 597   switch (header->_magic) {
 598   case CDS_PREIMAGE_ARCHIVE_MAGIC:
 599     return false; // This is a binary config file, not a proper archive
 600   case CDS_DYNAMIC_ARCHIVE_MAGIC:
 601     break;
 602   default:
 603     assert(header->_magic == CDS_ARCHIVE_MAGIC, "must be");
 604     if (AutoCreateSharedArchive) {
 605      aot_log_warning(aot)("AutoCreateSharedArchive is ignored because %s is a static archive", archive_name);
 606     }
 607     return true;
 608   }
 609 
 610   const char* base = file_helper.base_archive_name();
 611   if (base == nullptr) {
 612     *base_archive_name = CDSConfig::default_archive_path();
 613   } else {
 614     *base_archive_name = os::strdup_check_oom(base);
 615   }
 616 
 617   return true;
 618 }
 619 
 620 bool FileMapInfo::is_preimage_static_archive(const char* file) {
 621   FileHeaderHelper file_helper(file, false);
 622   if (!file_helper.initialize()) {
 623     return false;
 624   }
 625   return file_helper.is_preimage_static_archive();
 626 }
 627 
 628 // Read the FileMapInfo information from the file.
 629 
 630 bool FileMapInfo::init_from_file(int fd) {
 631   FileHeaderHelper file_helper(_full_path, _is_static);
 632   if (!file_helper.initialize(fd)) {
 633     aot_log_warning(aot)("Unable to read the file header.");
 634     return false;
 635   }
 636   GenericCDSFileMapHeader* gen_header = file_helper.get_generic_file_header();
 637 
 638   const char* file_type = CDSConfig::type_of_archive_being_loaded();
 639   if (_is_static) {
 640     if ((gen_header->_magic == CDS_ARCHIVE_MAGIC) ||
 641         (gen_header->_magic == CDS_PREIMAGE_ARCHIVE_MAGIC && CDSConfig::is_dumping_final_static_archive())) {
 642       // Good
 643     } else {
 644       if (CDSConfig::new_aot_flags_used()) {
 645         aot_log_warning(aot)("Not a valid %s (%s)", file_type, _full_path);
 646       } else {
 647         aot_log_warning(aot)("Not a base shared archive: %s", _full_path);
 648       }
 649       return false;
 650     }
 651   } else {
 652     if (gen_header->_magic != CDS_DYNAMIC_ARCHIVE_MAGIC) {
 653       aot_log_warning(aot)("Not a top shared archive: %s", _full_path);
 654       return false;
 655     }
 656   }
 657 
 658   _header = (FileMapHeader*)os::malloc(gen_header->_header_size, mtInternal);
 659   os::lseek(fd, 0, SEEK_SET); // reset to begin of the archive
 660   size_t size = gen_header->_header_size;
 661   size_t n = ::read(fd, (void*)_header, (unsigned int)size);
 662   if (n != size) {
 663     aot_log_warning(aot)("Failed to read file header from the top archive file\n");
 664     return false;
 665   }
 666 
 667   if (header()->version() != CURRENT_CDS_ARCHIVE_VERSION) {
 668     aot_log_info(aot)("_version expected: 0x%x", CURRENT_CDS_ARCHIVE_VERSION);
 669     aot_log_info(aot)("           actual: 0x%x", header()->version());
 670     aot_log_warning(aot)("The %s has the wrong version.", file_type);
 671     return false;
 672   }
 673 
 674   unsigned int base_offset = header()->base_archive_name_offset();
 675   unsigned int name_size = header()->base_archive_name_size();
 676   unsigned int header_size = header()->header_size();
 677   if (base_offset != 0 && name_size != 0) {
 678     if (header_size != base_offset + name_size) {
 679       aot_log_info(aot)("_header_size: " UINT32_FORMAT, header_size);
 680       aot_log_info(aot)("base_archive_name_size: " UINT32_FORMAT, header()->base_archive_name_size());
 681       aot_log_info(aot)("base_archive_name_offset: " UINT32_FORMAT, header()->base_archive_name_offset());
 682       aot_log_warning(aot)("The %s has an incorrect header size.", file_type);
 683       return false;
 684     }
 685   }
 686 
 687   const char* actual_ident = header()->jvm_ident();
 688 
 689   if (actual_ident[JVM_IDENT_MAX-1] != 0) {
 690     aot_log_warning(aot)("JVM version identifier is corrupted.");
 691     return false;
 692   }
 693 
 694   char expected_ident[JVM_IDENT_MAX];
 695   get_header_version(expected_ident);
 696   if (strncmp(actual_ident, expected_ident, JVM_IDENT_MAX-1) != 0) {
 697     aot_log_info(aot)("_jvm_ident expected: %s", expected_ident);
 698     aot_log_info(aot)("             actual: %s", actual_ident);
 699     aot_log_warning(aot)("The %s was created by a different"
 700                   " version or build of HotSpot", file_type);
 701     return false;
 702   }
 703 
 704   _file_offset = header()->header_size(); // accounts for the size of _base_archive_name
 705 
 706   size_t len = os::lseek(fd, 0, SEEK_END);
 707 
 708   for (int i = 0; i < AOTMetaspace::n_regions; i++) {
 709     FileMapRegion* r = region_at(i);
 710     if (r->file_offset() > len || len - r->file_offset() < r->used()) {
 711       aot_log_warning(aot)("The %s has been truncated.", file_type);
 712       return false;
 713     }
 714   }
 715 
 716   return true;
 717 }
 718 
 719 void FileMapInfo::seek_to_position(size_t pos) {
 720   if (os::lseek(_fd, (long)pos, SEEK_SET) < 0) {
 721     aot_log_error(aot)("Unable to seek to position %zu", pos);
 722     AOTMetaspace::unrecoverable_loading_error();
 723   }
 724 }
 725 
 726 // Read the FileMapInfo information from the file.
 727 bool FileMapInfo::open_for_read() {
 728   if (_file_open) {
 729     return true;
 730   }
 731   const char* file_type = CDSConfig::type_of_archive_being_loaded();
 732   const char* info = CDSConfig::is_dumping_final_static_archive() ?
 733     "AOTConfiguration file " : "";
 734   aot_log_info(aot)("trying to map %s%s", info, _full_path);
 735   int fd = os::open(_full_path, O_RDONLY | O_BINARY, 0);
 736   if (fd < 0) {
 737     if (errno == ENOENT) {
 738       aot_log_info(aot)("Specified %s not found (%s)", file_type, _full_path);
 739     } else {
 740       aot_log_warning(aot)("Failed to open %s (%s)", file_type,
 741                     os::strerror(errno));
 742     }
 743     return false;
 744   } else {
 745     aot_log_info(aot)("Opened %s %s.", file_type, _full_path);
 746   }
 747 
 748   _fd = fd;
 749   _file_open = true;
 750   return true;
 751 }
 752 
 753 // Write the FileMapInfo information to the file.
 754 
 755 void FileMapInfo::open_as_output() {
 756   if (CDSConfig::new_aot_flags_used()) {
 757     if (CDSConfig::is_dumping_preimage_static_archive()) {
 758       log_info(aot)("Writing binary AOTConfiguration file: %s",  _full_path);
 759     } else {
 760       log_info(aot)("Writing AOTCache file: %s",  _full_path);
 761     }
 762   } else {
 763     aot_log_info(aot)("Dumping shared data to file: %s", _full_path);
 764   }
 765 
 766 #ifdef _WINDOWS  // On Windows, need WRITE permission to remove the file.
 767   chmod(_full_path, _S_IREAD | _S_IWRITE);
 768 #endif
 769 
 770   // Use remove() to delete the existing file because, on Unix, this will
 771   // allow processes that have it open continued access to the file.
 772   remove(_full_path);
 773   int fd = os::open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0666);
 774   if (fd < 0) {
 775     aot_log_error(aot)("Unable to create %s %s: (%s).", CDSConfig::type_of_archive_being_written(), _full_path,
 776                    os::strerror(errno));
 777     AOTMetaspace::writing_error();
 778     return;
 779   }
 780   _fd = fd;
 781   _file_open = true;
 782 }
 783 
 784 void FileMapInfo::prepare_for_writing() {
 785   // Seek past the header. We will write the header after all regions are written
 786   // and their CRCs computed.
 787   size_t header_bytes = header()->header_size();
 788 
 789   header_bytes = align_up(header_bytes, AOTMetaspace::core_region_alignment());
 790   _file_offset = header_bytes;
 791   seek_to_position(_file_offset);
 792 }
 793 
 794 // Write the header to the file, seek to the next allocation boundary.
 795 
 796 void FileMapInfo::write_header() {
 797   _file_offset = 0;
 798   seek_to_position(_file_offset);
 799   assert(is_file_position_aligned(), "must be");
 800   write_bytes(header(), header()->header_size());
 801 }
 802 
 803 size_t FileMapRegion::used_aligned() const {
 804   return align_up(used(), AOTMetaspace::core_region_alignment());
 805 }
 806 
 807 void FileMapRegion::init(int region_index, size_t mapping_offset, size_t size, bool read_only,
 808                          bool allow_exec, int crc) {
 809   _is_heap_region = HeapShared::is_heap_region(region_index);
 810   _is_bitmap_region = (region_index == AOTMetaspace::bm);
 811   _mapping_offset = mapping_offset;
 812   _used = size;
 813   _read_only = read_only;
 814   _allow_exec = allow_exec;
 815   _crc = crc;
 816   _mapped_from_file = false;
 817   _mapped_base = nullptr;
 818   _in_reserved_space = false;
 819 }
 820 
 821 void FileMapRegion::init_oopmap(size_t offset, size_t size_in_bits) {
 822   _oopmap_offset = offset;
 823   _oopmap_size_in_bits = size_in_bits;
 824 }
 825 
 826 void FileMapRegion::init_ptrmap(size_t offset, size_t size_in_bits) {
 827   _ptrmap_offset = offset;
 828   _ptrmap_size_in_bits = size_in_bits;
 829 }
 830 
 831 bool FileMapRegion::check_region_crc(char* base) const {
 832   // This function should be called after the region has been properly
 833   // loaded into memory via FileMapInfo::map_region() or FileMapInfo::read_region().
 834   // I.e., this->mapped_base() must be valid.
 835   size_t sz = used();
 836   if (sz == 0) {
 837     return true;
 838   }
 839 
 840   assert(base != nullptr, "must be initialized");
 841   int crc = ClassLoader::crc32(0, base, (jint)sz);
 842   if (crc != this->crc()) {
 843     aot_log_warning(aot)("Checksum verification failed.");
 844     return false;
 845   }
 846   return true;
 847 }
 848 
 849 static const char* region_name(int region_index) {
 850   static const char* names[] = {
 851     "rw", "ro", "bm", "hp", "ac"
 852   };
 853   const int num_regions = sizeof(names)/sizeof(names[0]);
 854   assert(0 <= region_index && region_index < num_regions, "sanity");
 855 
 856   return names[region_index];
 857 }
 858 
 859 BitMapView FileMapInfo::bitmap_view(int region_index, bool is_oopmap) {
 860   FileMapRegion* r = region_at(region_index);
 861   char* bitmap_base = is_static() ? FileMapInfo::current_info()->map_bitmap_region() : FileMapInfo::dynamic_info()->map_bitmap_region();
 862   bitmap_base += is_oopmap ? r->oopmap_offset() : r->ptrmap_offset();
 863   size_t size_in_bits = is_oopmap ? r->oopmap_size_in_bits() : r->ptrmap_size_in_bits();
 864 
 865   aot_log_debug(aot, reloc)("mapped %s relocation %smap @ " INTPTR_FORMAT " (%zu bits)",
 866                         region_name(region_index), is_oopmap ? "oop" : "ptr",
 867                         p2i(bitmap_base), size_in_bits);
 868 
 869   return BitMapView((BitMap::bm_word_t*)(bitmap_base), size_in_bits);
 870 }
 871 
 872 BitMapView FileMapInfo::oopmap_view(int region_index) {
 873     return bitmap_view(region_index, /*is_oopmap*/true);
 874   }
 875 
 876 BitMapView FileMapInfo::ptrmap_view(int region_index) {
 877   return bitmap_view(region_index, /*is_oopmap*/false);
 878 }
 879 
 880 void FileMapRegion::print(outputStream* st, int region_index) {
 881   st->print_cr("============ region ============= %d \"%s\"", region_index, region_name(region_index));
 882   st->print_cr("- crc:                            0x%08x", _crc);
 883   st->print_cr("- read_only:                      %d", _read_only);
 884   st->print_cr("- allow_exec:                     %d", _allow_exec);
 885   st->print_cr("- is_heap_region:                 %d", _is_heap_region);
 886   st->print_cr("- is_bitmap_region:               %d", _is_bitmap_region);
 887   st->print_cr("- mapped_from_file:               %d", _mapped_from_file);
 888   st->print_cr("- file_offset:                    0x%zx", _file_offset);
 889   st->print_cr("- mapping_offset:                 0x%zx", _mapping_offset);
 890   st->print_cr("- used:                           %zu", _used);
 891   st->print_cr("- oopmap_offset:                  0x%zx", _oopmap_offset);
 892   st->print_cr("- oopmap_size_in_bits:            %zu", _oopmap_size_in_bits);
 893   st->print_cr("- ptrmap_offset:                  0x%zx", _ptrmap_offset);
 894   st->print_cr("- ptrmap_size_in_bits:            %zu", _ptrmap_size_in_bits);
 895   st->print_cr("- mapped_base:                    " INTPTR_FORMAT, p2i(_mapped_base));
 896 }
 897 
 898 void FileMapInfo::write_region(int region, char* base, size_t size,
 899                                bool read_only, bool allow_exec) {
 900   assert(CDSConfig::is_dumping_archive(), "sanity");
 901 
 902   FileMapRegion* r = region_at(region);
 903   char* requested_base;
 904   size_t mapping_offset = 0;
 905 
 906   if (region == AOTMetaspace::bm) {
 907     requested_base = nullptr; // always null for bm region
 908   } else if (size == 0) {
 909     // This is an unused region (e.g., a heap region when !INCLUDE_CDS_JAVA_HEAP)
 910     requested_base = nullptr;
 911   } else if (HeapShared::is_heap_region(region)) {
 912     assert(CDSConfig::is_dumping_heap(), "sanity");
 913 #if INCLUDE_CDS_JAVA_HEAP
 914     assert(!CDSConfig::is_dumping_dynamic_archive(), "must be");
 915     if (HeapShared::is_writing_mapping_mode()) {
 916       requested_base = (char*)AOTMappedHeapWriter::requested_address();
 917       if (UseCompressedOops) {
 918         mapping_offset = (size_t)((address)requested_base - AOTMappedHeapWriter::narrow_oop_base());
 919         assert((mapping_offset >> CompressedOops::shift()) << CompressedOops::shift() == mapping_offset, "must be");
 920       }
 921     } else {
 922       requested_base = nullptr;
 923     }
 924 #endif // INCLUDE_CDS_JAVA_HEAP
 925   } else {
 926     char* requested_SharedBaseAddress = (char*)AOTMetaspace::requested_base_address();
 927     requested_base = ArchiveBuilder::current()->to_requested(base);
 928     assert(requested_base >= requested_SharedBaseAddress, "must be");
 929     mapping_offset = requested_base - requested_SharedBaseAddress;
 930   }
 931 
 932   r->set_file_offset(_file_offset);
 933   int crc = ClassLoader::crc32(0, base, (jint)size);
 934   if (size > 0) {
 935     aot_log_info(aot)("Shared file region (%s) %d: %8zu"
 936                    " bytes, addr " INTPTR_FORMAT " file offset 0x%08" PRIxPTR
 937                    " crc 0x%08x",
 938                    region_name(region), region, size, p2i(requested_base), _file_offset, crc);
 939   } else {
 940     aot_log_info(aot)("Shared file region (%s) %d: %8zu"
 941                    " bytes", region_name(region), region, size);
 942   }
 943 
 944   r->init(region, mapping_offset, size, read_only, allow_exec, crc);
 945 
 946   if (base != nullptr) {
 947     write_bytes_aligned(base, size);
 948   }
 949 }
 950 
 951 static size_t write_bitmap(const CHeapBitMap* map, char* output, size_t offset) {
 952   size_t size_in_bytes = map->size_in_bytes();
 953   map->write_to((BitMap::bm_word_t*)(output + offset), size_in_bytes);
 954   return offset + size_in_bytes;
 955 }
 956 
 957 // The sorting code groups the objects with non-null oop/ptrs together.
 958 // Relevant bitmaps then have lots of leading and trailing zeros, which
 959 // we do not have to store.
 960 size_t FileMapInfo::remove_bitmap_zeros(CHeapBitMap* map) {
 961   BitMap::idx_t first_set = map->find_first_set_bit(0);
 962   BitMap::idx_t last_set  = map->find_last_set_bit(0);
 963   size_t old_size = map->size();
 964 
 965   // Slice and resize bitmap
 966   map->truncate(first_set, last_set + 1);
 967 
 968   assert(map->at(0), "First bit should be set");
 969   assert(map->at(map->size() - 1), "Last bit should be set");
 970   assert(map->size() <= old_size, "sanity");
 971 
 972   return first_set;
 973 }
 974 
 975 char* FileMapInfo::write_bitmap_region(CHeapBitMap* rw_ptrmap,
 976                                        CHeapBitMap* ro_ptrmap,
 977                                        ArchiveMappedHeapInfo* mapped_heap_info,
 978                                        ArchiveStreamedHeapInfo* streamed_heap_info,
 979                                        size_t &size_in_bytes) {
 980   size_t removed_rw_leading_zeros = remove_bitmap_zeros(rw_ptrmap);
 981   size_t removed_ro_leading_zeros = remove_bitmap_zeros(ro_ptrmap);
 982   header()->set_rw_ptrmap_start_pos(removed_rw_leading_zeros);
 983   header()->set_ro_ptrmap_start_pos(removed_ro_leading_zeros);
 984   size_in_bytes = rw_ptrmap->size_in_bytes() + ro_ptrmap->size_in_bytes();
 985 
 986   if (mapped_heap_info != nullptr && mapped_heap_info->is_used()) {
 987     // Remove leading and trailing zeros
 988     assert(HeapShared::is_writing_mapping_mode(), "unexpected dumping mode");
 989     size_t removed_oop_leading_zeros = remove_bitmap_zeros(mapped_heap_info->oopmap());
 990     size_t removed_ptr_leading_zeros = remove_bitmap_zeros(mapped_heap_info->ptrmap());
 991     mapped_heap_info->set_oopmap_start_pos(removed_oop_leading_zeros);
 992     mapped_heap_info->set_ptrmap_start_pos(removed_ptr_leading_zeros);
 993 
 994     size_in_bytes += mapped_heap_info->oopmap()->size_in_bytes();
 995     size_in_bytes += mapped_heap_info->ptrmap()->size_in_bytes();
 996   } else if (streamed_heap_info != nullptr && streamed_heap_info->is_used()) {
 997     assert(HeapShared::is_writing_streaming_mode(), "unexpected dumping mode");
 998 
 999     size_in_bytes += streamed_heap_info->oopmap()->size_in_bytes();
1000   }
1001 
1002   // The bitmap region contains up to 4 parts:
1003   // rw_ptrmap:                  metaspace pointers inside the read-write region
1004   // ro_ptrmap:                  metaspace pointers inside the read-only region
1005   // *_heap_info->oopmap():      Java oop pointers in the heap region
1006   // mapped_heap_info->ptrmap(): metaspace pointers in the heap region
1007   char* buffer = NEW_C_HEAP_ARRAY(char, size_in_bytes, mtClassShared);
1008   size_t written = 0;
1009 
1010   region_at(AOTMetaspace::rw)->init_ptrmap(0, rw_ptrmap->size());
1011   written = write_bitmap(rw_ptrmap, buffer, written);
1012 
1013   region_at(AOTMetaspace::ro)->init_ptrmap(written, ro_ptrmap->size());
1014   written = write_bitmap(ro_ptrmap, buffer, written);
1015 
1016   if (mapped_heap_info != nullptr && mapped_heap_info->is_used()) {
1017     assert(HeapShared::is_writing_mapping_mode(), "unexpected dumping mode");
1018     FileMapRegion* r = region_at(AOTMetaspace::hp);
1019 
1020     r->init_oopmap(written, mapped_heap_info->oopmap()->size());
1021     written = write_bitmap(mapped_heap_info->oopmap(), buffer, written);
1022 
1023     r->init_ptrmap(written, mapped_heap_info->ptrmap()->size());
1024     written = write_bitmap(mapped_heap_info->ptrmap(), buffer, written);
1025   } else if (streamed_heap_info != nullptr && streamed_heap_info->is_used()) {
1026     assert(HeapShared::is_writing_streaming_mode(), "unexpected dumping mode");
1027     FileMapRegion* r = region_at(AOTMetaspace::hp);
1028 
1029     r->init_oopmap(written, streamed_heap_info->oopmap()->size());
1030     written = write_bitmap(streamed_heap_info->oopmap(), buffer, written);
1031   }
1032 
1033   write_region(AOTMetaspace::bm, (char*)buffer, size_in_bytes, /*read_only=*/true, /*allow_exec=*/false);
1034   return buffer;
1035 }
1036 
1037 #if INCLUDE_CDS_JAVA_HEAP
1038 size_t FileMapInfo::write_mapped_heap_region(ArchiveMappedHeapInfo* heap_info) {
1039   char* buffer_start = heap_info->buffer_start();
1040   size_t buffer_size = heap_info->buffer_byte_size();
1041   write_region(AOTMetaspace::hp, buffer_start, buffer_size, false, false);
1042   header()->set_mapped_heap_header(heap_info->create_header());
1043   return buffer_size;
1044 }
1045 
1046 size_t FileMapInfo::write_streamed_heap_region(ArchiveStreamedHeapInfo* heap_info) {
1047   char* buffer_start = heap_info->buffer_start();
1048   size_t buffer_size = heap_info->buffer_byte_size();
1049   write_region(AOTMetaspace::hp, buffer_start, buffer_size, true, false);
1050   header()->set_streamed_heap_header(heap_info->create_header());
1051   return buffer_size;
1052 }
1053 #endif // INCLUDE_CDS_JAVA_HEAP
1054 
1055 // Dump bytes to file -- at the current file position.
1056 
1057 void FileMapInfo::write_bytes(const void* buffer, size_t nbytes) {
1058   assert(_file_open, "must be");
1059   if (!os::write(_fd, buffer, nbytes)) {
1060     // If the shared archive is corrupted, close it and remove it.
1061     close();
1062     remove(_full_path);
1063 
1064     if (CDSConfig::is_dumping_preimage_static_archive()) {
1065       AOTMetaspace::writing_error("Unable to write to AOT configuration file.");
1066     } else if (CDSConfig::new_aot_flags_used()) {
1067       AOTMetaspace::writing_error("Unable to write to AOT cache.");
1068     } else {
1069       AOTMetaspace::writing_error("Unable to write to shared archive.");
1070     }
1071   }
1072   _file_offset += nbytes;
1073 }
1074 
1075 bool FileMapInfo::is_file_position_aligned() const {
1076   return _file_offset == align_up(_file_offset,
1077                                   AOTMetaspace::core_region_alignment());
1078 }
1079 
1080 // Align file position to an allocation unit boundary.
1081 
1082 void FileMapInfo::align_file_position() {
1083   assert(_file_open, "must be");
1084   size_t new_file_offset = align_up(_file_offset,
1085                                     AOTMetaspace::core_region_alignment());
1086   if (new_file_offset != _file_offset) {
1087     _file_offset = new_file_offset;
1088     // Seek one byte back from the target and write a byte to insure
1089     // that the written file is the correct length.
1090     _file_offset -= 1;
1091     seek_to_position(_file_offset);
1092     char zero = 0;
1093     write_bytes(&zero, 1);
1094   }
1095 }
1096 
1097 
1098 // Dump bytes to file -- at the current file position.
1099 
1100 void FileMapInfo::write_bytes_aligned(const void* buffer, size_t nbytes) {
1101   align_file_position();
1102   write_bytes(buffer, nbytes);
1103   align_file_position();
1104 }
1105 
1106 // Close the shared archive file.  This does NOT unmap mapped regions.
1107 
1108 void FileMapInfo::close() {
1109   if (_file_open) {
1110     if (::close(_fd) < 0) {
1111       AOTMetaspace::unrecoverable_loading_error("Unable to close the shared archive file.");
1112     }
1113     _file_open = false;
1114     _fd = -1;
1115   }
1116 }
1117 
1118 /*
1119  * Same as os::map_memory() but also pretouches if AlwaysPreTouch is enabled.
1120  */
1121 static char* map_memory(int fd, const char* file_name, size_t file_offset,
1122                         char* addr, size_t bytes, bool read_only,
1123                         bool allow_exec, MemTag mem_tag) {
1124   char* mem = os::map_memory(fd, file_name, file_offset, addr, bytes,
1125                              mem_tag, AlwaysPreTouch ? false : read_only,
1126                              allow_exec);
1127   if (mem != nullptr && AlwaysPreTouch) {
1128     os::pretouch_memory(mem, mem + bytes);
1129   }
1130   return mem;
1131 }
1132 
1133 char* FileMapInfo::map_heap_region(FileMapRegion* r, char* addr, size_t bytes) {
1134   return ::map_memory(_fd,
1135                     _full_path,
1136                     r->file_offset(),
1137                     addr,
1138                     bytes,
1139                     r->read_only(),
1140                     r->allow_exec(),
1141                     mtJavaHeap);
1142 }
1143 
1144 // JVM/TI RedefineClasses() support:
1145 // Remap the shared readonly space to shared readwrite, private.
1146 bool FileMapInfo::remap_shared_readonly_as_readwrite() {
1147   int idx = AOTMetaspace::ro;
1148   FileMapRegion* r = region_at(idx);
1149   if (!r->read_only()) {
1150     // the space is already readwrite so we are done
1151     return true;
1152   }
1153   size_t size = r->used_aligned();
1154   if (!open_for_read()) {
1155     return false;
1156   }
1157   char *addr = r->mapped_base();
1158   // This path should not be reached for Windows; see JDK-8222379.
1159   assert(WINDOWS_ONLY(false) NOT_WINDOWS(true), "Don't call on Windows");
1160   // Replace old mapping with new one that is writable.
1161   char *base = os::map_memory(_fd, _full_path, r->file_offset(),
1162                               addr, size, mtNone, false /* !read_only */,
1163                               r->allow_exec());
1164   close();
1165   // These have to be errors because the shared region is now unmapped.
1166   if (base == nullptr) {
1167     aot_log_error(aot)("Unable to remap shared readonly space (errno=%d).", errno);
1168     vm_exit(1);
1169   }
1170   if (base != addr) {
1171     aot_log_error(aot)("Unable to remap shared readonly space (errno=%d).", errno);
1172     vm_exit(1);
1173   }
1174   r->set_read_only(false);
1175   return true;
1176 }
1177 
1178 // Memory map a region in the address space.
1179 static const char* shared_region_name[] = { "ReadWrite", "ReadOnly", "Bitmap", "Heap", "Code" };
1180 
1181 MapArchiveResult FileMapInfo::map_regions(int regions[], int num_regions, char* mapped_base_address, ReservedSpace rs) {
1182   DEBUG_ONLY(FileMapRegion* last_region = nullptr);
1183   intx addr_delta = mapped_base_address - header()->requested_base_address();
1184 
1185   // Make sure we don't attempt to use header()->mapped_base_address() unless
1186   // it's been successfully mapped.
1187   DEBUG_ONLY(header()->set_mapped_base_address((char*)(uintptr_t)0xdeadbeef);)
1188 
1189   for (int i = 0; i < num_regions; i++) {
1190     int idx = regions[i];
1191     MapArchiveResult result = map_region(idx, addr_delta, mapped_base_address, rs);
1192     if (result != MAP_ARCHIVE_SUCCESS) {
1193       return result;
1194     }
1195     FileMapRegion* r = region_at(idx);
1196     DEBUG_ONLY(if (last_region != nullptr) {
1197         // Ensure that the OS won't be able to allocate new memory spaces between any mapped
1198         // regions, or else it would mess up the simple comparison in MetaspaceObj::in_aot_cache().
1199         assert(r->mapped_base() == last_region->mapped_end(), "must have no gaps");
1200       }
1201       last_region = r;)
1202     aot_log_info(aot)("Mapped %s region #%d at base " INTPTR_FORMAT " top " INTPTR_FORMAT " (%s)", is_static() ? "static " : "dynamic",
1203                   idx, p2i(r->mapped_base()), p2i(r->mapped_end()),
1204                   shared_region_name[idx]);
1205 
1206   }
1207 
1208   header()->set_mapped_base_address(header()->requested_base_address() + addr_delta);
1209   if (addr_delta != 0 && !relocate_pointers_in_core_regions(addr_delta)) {
1210     return MAP_ARCHIVE_OTHER_FAILURE;
1211   }
1212 
1213   return MAP_ARCHIVE_SUCCESS;
1214 }
1215 
1216 bool FileMapInfo::read_region(int i, char* base, size_t size, bool do_commit) {
1217   FileMapRegion* r = region_at(i);
1218   if (do_commit) {
1219     aot_log_info(aot)("Commit %s region #%d at base " INTPTR_FORMAT " top " INTPTR_FORMAT " (%s)%s",
1220                   is_static() ? "static " : "dynamic", i, p2i(base), p2i(base + size),
1221                   shared_region_name[i], r->allow_exec() ? " exec" : "");
1222     if (!os::commit_memory(base, size, r->allow_exec())) {
1223       aot_log_error(aot)("Failed to commit %s region #%d (%s)", is_static() ? "static " : "dynamic",
1224                      i, shared_region_name[i]);
1225       return false;
1226     }
1227   }
1228   if (os::lseek(_fd, (long)r->file_offset(), SEEK_SET) != (int)r->file_offset() ||
1229       read_bytes(base, size) != size) {
1230     return false;
1231   }
1232 
1233   if (VerifySharedSpaces && !r->check_region_crc(base)) {
1234     return false;
1235   }
1236 
1237   r->set_mapped_from_file(false);
1238   r->set_mapped_base(base);
1239 
1240   return true;
1241 }
1242 
1243 MapArchiveResult FileMapInfo::map_region(int i, intx addr_delta, char* mapped_base_address, ReservedSpace rs) {
1244   assert(!HeapShared::is_heap_region(i), "sanity");
1245   FileMapRegion* r = region_at(i);
1246   size_t size = r->used_aligned();
1247   char *requested_addr = mapped_base_address + r->mapping_offset();
1248   assert(!is_mapped(), "must be not mapped yet");
1249   assert(requested_addr != nullptr, "must be specified");
1250 
1251   r->set_mapped_from_file(false);
1252   r->set_in_reserved_space(false);
1253 
1254   if (AOTMetaspace::use_windows_memory_mapping()) {
1255     // Windows cannot remap read-only shared memory to read-write when required for
1256     // RedefineClasses, which is also used by JFR.  Always map windows regions as RW.
1257     r->set_read_only(false);
1258   } else if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space() ||
1259              Arguments::has_jfr_option()) {
1260     // If a tool agent is in use (debugging enabled), or JFR, we must map the address space RW
1261     r->set_read_only(false);
1262   } else if (addr_delta != 0) {
1263     r->set_read_only(false); // Need to patch the pointers
1264   }
1265 
1266   if (AOTMetaspace::use_windows_memory_mapping() && rs.is_reserved()) {
1267     // This is the second time we try to map the archive(s). We have already created a ReservedSpace
1268     // that covers all the FileMapRegions to ensure all regions can be mapped. However, Windows
1269     // can't mmap into a ReservedSpace, so we just ::read() the data. We're going to patch all the
1270     // regions anyway, so there's no benefit for mmap anyway.
1271     if (!read_region(i, requested_addr, size, /* do_commit = */ true)) {
1272       AOTMetaspace::report_loading_error("Failed to read %s shared space into reserved space at " INTPTR_FORMAT,
1273                                             shared_region_name[i], p2i(requested_addr));
1274       return MAP_ARCHIVE_OTHER_FAILURE; // oom or I/O error.
1275     } else {
1276       assert(r->mapped_base() != nullptr, "must be initialized");
1277     }
1278   } else {
1279     // Note that this may either be a "fresh" mapping into unreserved address
1280     // space (Windows, first mapping attempt), or a mapping into pre-reserved
1281     // space (Posix). See also comment in AOTMetaspace::map_archives().
1282     char* base = map_memory(_fd, _full_path, r->file_offset(),
1283                             requested_addr, size, r->read_only(),
1284                             r->allow_exec(), mtClassShared);
1285     if (base != requested_addr) {
1286       AOTMetaspace::report_loading_error("Unable to map %s shared space at " INTPTR_FORMAT,
1287                                             shared_region_name[i], p2i(requested_addr));
1288       _memory_mapping_failed = true;
1289       return MAP_ARCHIVE_MMAP_FAILURE;
1290     }
1291 
1292     if (VerifySharedSpaces && !r->check_region_crc(requested_addr)) {
1293       return MAP_ARCHIVE_OTHER_FAILURE;
1294     }
1295 
1296     r->set_mapped_from_file(true);
1297     r->set_mapped_base(requested_addr);
1298   }
1299 
1300   if (rs.is_reserved()) {
1301     char* mapped_base = r->mapped_base();
1302     assert(rs.base() <= mapped_base && mapped_base + size <= rs.end(),
1303            PTR_FORMAT " <= " PTR_FORMAT " < " PTR_FORMAT " <= " PTR_FORMAT,
1304            p2i(rs.base()), p2i(mapped_base), p2i(mapped_base + size), p2i(rs.end()));
1305     r->set_in_reserved_space(rs.is_reserved());
1306   }
1307   return MAP_ARCHIVE_SUCCESS;
1308 }
1309 
1310 // The return value is the location of the archive relocation bitmap.
1311 char* FileMapInfo::map_auxiliary_region(int region_index, bool read_only) {
1312   FileMapRegion* r = region_at(region_index);
1313   if (r->mapped_base() != nullptr) {
1314     return r->mapped_base();
1315   }
1316   const char* region_name = shared_region_name[region_index];
1317   bool allow_exec = false;
1318   char* requested_addr = nullptr; // allow OS to pick any location
1319   char* mapped_base = map_memory(_fd, _full_path, r->file_offset(),
1320                                  requested_addr, r->used_aligned(), read_only, allow_exec, mtClassShared);
1321   if (mapped_base == nullptr) {
1322     AOTMetaspace::report_loading_error("failed to map %d region", region_index);
1323     return nullptr;
1324   }
1325 
1326   if (VerifySharedSpaces && !r->check_region_crc(mapped_base)) {
1327     aot_log_error(aot)("region %d CRC error", region_index);
1328     if (!os::unmap_memory(mapped_base, r->used_aligned())) {
1329       fatal("os::unmap_memory of region %d failed", region_index);
1330     }
1331     return nullptr;
1332   }
1333 
1334   r->set_mapped_from_file(true);
1335   r->set_mapped_base(mapped_base);
1336   aot_log_info(aot)("Mapped %s region #%d at base %zu top %zu (%s)",
1337                 is_static() ? "static " : "dynamic",
1338                 region_index, p2i(r->mapped_base()), p2i(r->mapped_end()),
1339                 region_name);
1340   return mapped_base;
1341 }
1342 
1343 char* FileMapInfo::map_bitmap_region() {
1344   return map_auxiliary_region(AOTMetaspace::bm, false);
1345 }
1346 
1347 bool FileMapInfo::map_aot_code_region(ReservedSpace rs) {
1348   FileMapRegion* r = region_at(AOTMetaspace::ac);
1349   assert(r->used() > 0 && r->used_aligned() == rs.size(), "must be");
1350 
1351   char* requested_base = rs.base();
1352   assert(requested_base != nullptr, "should be inside code cache");
1353 
1354   char* mapped_base;
1355   if (AOTMetaspace::use_windows_memory_mapping()) {
1356     if (!read_region(AOTMetaspace::ac, requested_base, r->used_aligned(), /* do_commit = */ true)) {
1357       AOTMetaspace::report_loading_error("Failed to read aot code shared space into reserved space at " INTPTR_FORMAT,
1358                                             p2i(requested_base));
1359       return false;
1360     }
1361     mapped_base = requested_base;
1362   } else {
1363     // We do not execute in-place in the AOT code region.
1364     // AOT code is copied to the CodeCache for execution.
1365     bool read_only = false, allow_exec = false;
1366     mapped_base = map_memory(_fd, _full_path, r->file_offset(),
1367                              requested_base, r->used_aligned(), read_only, allow_exec, mtClassShared);
1368   }
1369   if (mapped_base == nullptr) {
1370     AOTMetaspace::report_loading_error("failed to map aot code region");
1371     return false;
1372   } else {
1373     assert(mapped_base == requested_base, "must be");
1374     r->set_mapped_from_file(true);
1375     r->set_mapped_base(mapped_base);
1376     aot_log_info(aot)("Mapped static  region #%d at base " INTPTR_FORMAT " top " INTPTR_FORMAT " (%s)",
1377                   AOTMetaspace::ac, p2i(r->mapped_base()), p2i(r->mapped_end()),
1378                   shared_region_name[AOTMetaspace::ac]);
1379     return true;
1380   }
1381 }
1382 
1383 class SharedDataRelocationTask : public ArchiveWorkerTask {
1384 private:
1385   BitMapView* const _rw_bm;
1386   BitMapView* const _ro_bm;
1387   SharedDataRelocator* const _rw_reloc;
1388   SharedDataRelocator* const _ro_reloc;
1389 
1390 public:
1391   SharedDataRelocationTask(BitMapView* rw_bm, BitMapView* ro_bm, SharedDataRelocator* rw_reloc, SharedDataRelocator* ro_reloc) :
1392                            ArchiveWorkerTask("Shared Data Relocation"),
1393                            _rw_bm(rw_bm), _ro_bm(ro_bm), _rw_reloc(rw_reloc), _ro_reloc(ro_reloc) {}
1394 
1395   void work(int chunk, int max_chunks) override {
1396     work_on(chunk, max_chunks, _rw_bm, _rw_reloc);
1397     work_on(chunk, max_chunks, _ro_bm, _ro_reloc);
1398   }
1399 
1400   void work_on(int chunk, int max_chunks, BitMapView* bm, SharedDataRelocator* reloc) {
1401     BitMap::idx_t size  = bm->size();
1402     BitMap::idx_t start = MIN2(size, size * chunk / max_chunks);
1403     BitMap::idx_t end   = MIN2(size, size * (chunk + 1) / max_chunks);
1404     assert(end > start, "Sanity: no empty slices");
1405     bm->iterate(reloc, start, end);
1406   }
1407 };
1408 
1409 // This is called when we cannot map the archive at the requested[ base address (usually 0x800000000).
1410 // We relocate all pointers in the 2 core regions (ro, rw).
1411 bool FileMapInfo::relocate_pointers_in_core_regions(intx addr_delta) {
1412   aot_log_debug(aot, reloc)("runtime archive relocation start");
1413   char* bitmap_base = map_bitmap_region();
1414 
1415   if (bitmap_base == nullptr) {
1416     return false; // OOM, or CRC check failure
1417   } else {
1418     BitMapView rw_ptrmap = ptrmap_view(AOTMetaspace::rw);
1419     BitMapView ro_ptrmap = ptrmap_view(AOTMetaspace::ro);
1420 
1421     FileMapRegion* rw_region = first_core_region();
1422     FileMapRegion* ro_region = last_core_region();
1423 
1424     // Patch all pointers inside the RW region
1425     address rw_patch_base = (address)rw_region->mapped_base();
1426     address rw_patch_end  = (address)rw_region->mapped_end();
1427 
1428     // Patch all pointers inside the RO region
1429     address ro_patch_base = (address)ro_region->mapped_base();
1430     address ro_patch_end  = (address)ro_region->mapped_end();
1431 
1432     // the current value of the pointers to be patched must be within this
1433     // range (i.e., must be between the requested base address and the address of the current archive).
1434     // Note: top archive may point to objects in the base archive, but not the other way around.
1435     address valid_old_base = (address)header()->requested_base_address();
1436     address valid_old_end  = valid_old_base + mapping_end_offset();
1437 
1438     // after patching, the pointers must point inside this range
1439     // (the requested location of the archive, as mapped at runtime).
1440     address valid_new_base = (address)header()->mapped_base_address();
1441     address valid_new_end  = (address)mapped_end();
1442 
1443     SharedDataRelocator rw_patcher((address*)rw_patch_base + header()->rw_ptrmap_start_pos(), (address*)rw_patch_end, valid_old_base, valid_old_end,
1444                                 valid_new_base, valid_new_end, addr_delta);
1445     SharedDataRelocator ro_patcher((address*)ro_patch_base + header()->ro_ptrmap_start_pos(), (address*)ro_patch_end, valid_old_base, valid_old_end,
1446                                 valid_new_base, valid_new_end, addr_delta);
1447 
1448     if (AOTCacheParallelRelocation) {
1449       ArchiveWorkers workers;
1450       SharedDataRelocationTask task(&rw_ptrmap, &ro_ptrmap, &rw_patcher, &ro_patcher);
1451       workers.run_task(&task);
1452     } else {
1453       rw_ptrmap.iterate(&rw_patcher);
1454       ro_ptrmap.iterate(&ro_patcher);
1455     }
1456 
1457     // The AOTMetaspace::bm region will be unmapped in AOTMetaspace::initialize_shared_spaces().
1458 
1459     aot_log_debug(aot, reloc)("runtime archive relocation done");
1460     return true;
1461   }
1462 }
1463 
1464 size_t FileMapInfo::read_bytes(void* buffer, size_t count) {
1465   assert(_file_open, "Archive file is not open");
1466   size_t n = ::read(_fd, buffer, (unsigned int)count);
1467   if (n != count) {
1468     // Close the file if there's a problem reading it.
1469     close();
1470     return 0;
1471   }
1472   _file_offset += count;
1473   return count;
1474 }
1475 
1476 // Get the total size in bytes of a read only region
1477 size_t FileMapInfo::readonly_total() {
1478   size_t total = 0;
1479   if (current_info() != nullptr) {
1480     FileMapRegion* r = FileMapInfo::current_info()->region_at(AOTMetaspace::ro);
1481     if (r->read_only()) total += r->used();
1482   }
1483   if (dynamic_info() != nullptr) {
1484     FileMapRegion* r = FileMapInfo::dynamic_info()->region_at(AOTMetaspace::ro);
1485     if (r->read_only()) total += r->used();
1486   }
1487   return total;
1488 }
1489 
1490 #if INCLUDE_CDS_JAVA_HEAP
1491 
1492 bool FileMapInfo::has_heap_region() {
1493   return (region_at(AOTMetaspace::hp)->used() > 0);
1494 }
1495 
1496 static void on_heap_region_loading_error() {
1497   if (CDSConfig::is_using_aot_linked_classes()) {
1498     // It's too late to recover -- we have already committed to use the archived metaspace objects, but
1499     // the archived heap objects cannot be loaded, so we don't have the archived FMG to guarantee that
1500     // all AOT-linked classes are visible.
1501     //
1502     // We get here because the heap is too small. The app will fail anyway. So let's quit.
1503     aot_log_error(aot)("%s has aot-linked classes but the archived "
1504                        "heap objects cannot be loaded. Try increasing your heap size.",
1505                        CDSConfig::type_of_archive_being_loaded());
1506     AOTMetaspace::unrecoverable_loading_error();
1507   }
1508   CDSConfig::stop_using_full_module_graph();
1509 }
1510 
1511 void FileMapInfo::stream_heap_region() {
1512   assert(object_streaming_mode(), "This should only be done for the streaming approach");
1513 
1514   if (map_auxiliary_region(AOTMetaspace::hp, /*readonly=*/true) != nullptr) {
1515     HeapShared::initialize_streaming();
1516   } else {
1517     on_heap_region_loading_error();
1518   }
1519 }
1520 
1521 void FileMapInfo::map_or_load_heap_region() {
1522   assert(!object_streaming_mode(), "This should only be done for the mapping approach");
1523   bool success = false;
1524 
1525   if (AOTMappedHeapLoader::can_map()) {
1526     success = AOTMappedHeapLoader::map_heap_region(this);
1527   } else if (AOTMappedHeapLoader::can_load()) {
1528     success = AOTMappedHeapLoader::load_heap_region(this);
1529   }
1530 
1531   if (!success) {
1532     on_heap_region_loading_error();
1533   }
1534 }
1535 
1536 bool FileMapInfo::can_use_heap_region() {
1537   if (!has_heap_region()) {
1538     return false;
1539   }
1540   if (!object_streaming_mode() && !Universe::heap()->can_load_archived_objects() && !UseG1GC) {
1541     // Incompatible object format
1542     return false;
1543   }
1544   if (JvmtiExport::should_post_class_file_load_hook() && JvmtiExport::has_early_class_hook_env()) {
1545     ShouldNotReachHere(); // CDS should have been disabled.
1546     // The archived objects are mapped at JVM start-up, but we don't know if
1547     // j.l.String or j.l.Class might be replaced by the ClassFileLoadHook,
1548     // which would make the archived String or mirror objects invalid. Let's be safe and not
1549     // use the archived objects. These 2 classes are loaded during the JVMTI "early" stage.
1550     //
1551     // If JvmtiExport::has_early_class_hook_env() is false, the classes of some objects
1552     // in the archived subgraphs may be replaced by the ClassFileLoadHook. But that's OK
1553     // because we won't install an archived object subgraph if the klass of any of the
1554     // referenced objects are replaced. See HeapShared::initialize_from_archived_subgraph().
1555   }
1556 
1557   // We pre-compute narrow Klass IDs with the runtime mapping start intended to be the base, and a shift of
1558   // HeapShared::precomputed_narrow_klass_shift. We enforce this encoding at runtime (see
1559   // CompressedKlassPointers::initialize_for_given_encoding()). Therefore, the following assertions must
1560   // hold:
1561   address archive_narrow_klass_base = (address)header()->mapped_base_address();
1562   const int archive_narrow_klass_pointer_bits = header()->narrow_klass_pointer_bits();
1563   const int archive_narrow_klass_shift = header()->narrow_klass_shift();
1564 
1565   aot_log_info(aot)("CDS archive was created with max heap size = %zuM, and the following configuration:",
1566                 max_heap_size()/M);
1567 
1568   aot_log_info(aot)("    narrow_klass_base at mapping start address, narrow_klass_pointer_bits = %d, narrow_klass_shift = %d",
1569                 archive_narrow_klass_pointer_bits, archive_narrow_klass_shift);
1570   if (UseCompressedOops) {
1571     aot_log_info(aot)("    narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d",
1572                       narrow_oop_mode(), p2i(narrow_oop_base()), narrow_oop_shift());
1573   }
1574   aot_log_info(aot)("The current max heap size = %zuM, G1HeapRegion::GrainBytes = %zu",
1575                 MaxHeapSize/M, G1HeapRegion::GrainBytes);
1576   aot_log_info(aot)("    narrow_klass_base = " PTR_FORMAT ", arrow_klass_pointer_bits = %d, narrow_klass_shift = %d",
1577                 p2i(CompressedKlassPointers::base()), CompressedKlassPointers::narrow_klass_pointer_bits(), CompressedKlassPointers::shift());
1578   if (UseCompressedOops) {
1579     aot_log_info(aot)("    narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d",
1580                       CompressedOops::mode(), p2i(CompressedOops::base()), CompressedOops::shift());
1581   }
1582   if (!object_streaming_mode()) {
1583     aot_log_info(aot)("    heap range = [" PTR_FORMAT " - "  PTR_FORMAT "]",
1584                       UseCompressedOops ? p2i(CompressedOops::begin()) :
1585                       UseG1GC ? p2i((address)G1CollectedHeap::heap()->reserved().start()) : 0L,
1586                       UseCompressedOops ? p2i(CompressedOops::end()) :
1587                       UseG1GC ? p2i((address)G1CollectedHeap::heap()->reserved().end()) : 0L);
1588   }
1589 
1590   int err = 0;
1591   if ( archive_narrow_klass_base != CompressedKlassPointers::base() ||
1592        (err = 1, archive_narrow_klass_pointer_bits != CompressedKlassPointers::narrow_klass_pointer_bits()) ||
1593        (err = 2, archive_narrow_klass_shift != CompressedKlassPointers::shift()) ) {
1594     stringStream ss;
1595     switch (err) {
1596     case 0:
1597       ss.print("Unexpected encoding base encountered (" PTR_FORMAT ", expected " PTR_FORMAT ")",
1598                p2i(CompressedKlassPointers::base()), p2i(archive_narrow_klass_base));
1599       break;
1600     case 1:
1601       ss.print("Unexpected narrow Klass bit length encountered (%d, expected %d)",
1602                CompressedKlassPointers::narrow_klass_pointer_bits(), archive_narrow_klass_pointer_bits);
1603       break;
1604     case 2:
1605       ss.print("Unexpected narrow Klass shift encountered (%d, expected %d)",
1606                CompressedKlassPointers::shift(), archive_narrow_klass_shift);
1607       break;
1608     default:
1609       ShouldNotReachHere();
1610     };
1611     if (CDSConfig::new_aot_flags_used()) {
1612       LogTarget(Info, aot) lt;
1613       if (lt.is_enabled()) {
1614         LogStream ls(lt);
1615         ls.print_raw(ss.base());
1616         header()->print(&ls);
1617       }
1618     } else {
1619       LogTarget(Info, cds) lt;
1620       if (lt.is_enabled()) {
1621         LogStream ls(lt);
1622         ls.print_raw(ss.base());
1623         header()->print(&ls);
1624       }
1625     }
1626     assert(false, "%s", ss.base());
1627   }
1628 
1629   return true;
1630 }
1631 
1632 #endif // INCLUDE_CDS_JAVA_HEAP
1633 
1634 // Unmap a memory region in the address space.
1635 
1636 void FileMapInfo::unmap_regions(int regions[], int num_regions) {
1637   for (int r = 0; r < num_regions; r++) {
1638     int idx = regions[r];
1639     unmap_region(idx);
1640   }
1641 }
1642 
1643 void FileMapInfo::unmap_region(int i) {
1644   FileMapRegion* r = region_at(i);
1645   char* mapped_base = r->mapped_base();
1646   size_t size = r->used_aligned();
1647 
1648   if (mapped_base != nullptr) {
1649     if (size > 0 && r->mapped_from_file()) {
1650       aot_log_info(aot)("Unmapping region #%d at base " INTPTR_FORMAT " (%s)", i, p2i(mapped_base),
1651                     shared_region_name[i]);
1652       if (r->in_reserved_space()) {
1653         // This region was mapped inside a ReservedSpace. Its memory will be freed when the ReservedSpace
1654         // is released. Zero it so that we don't accidentally read its content.
1655         aot_log_info(aot)("Region #%d (%s) is in a reserved space, it will be freed when the space is released", i, shared_region_name[i]);
1656       } else {
1657         if (!os::unmap_memory(mapped_base, size)) {
1658           fatal("os::unmap_memory failed");
1659         }
1660       }
1661     }
1662     r->set_mapped_base(nullptr);
1663   }
1664 }
1665 
1666 void FileMapInfo::assert_mark(bool check) {
1667   if (!check) {
1668     AOTMetaspace::unrecoverable_loading_error("Mark mismatch while restoring from shared file.");
1669   }
1670 }
1671 
1672 FileMapInfo* FileMapInfo::_current_info = nullptr;
1673 FileMapInfo* FileMapInfo::_dynamic_archive_info = nullptr;
1674 bool FileMapInfo::_memory_mapping_failed = false;
1675 
1676 // Open the shared archive file, read and validate the header
1677 // information (version, boot classpath, etc.). If initialization
1678 // fails, shared spaces are disabled and the file is closed.
1679 //
1680 // Validation of the archive is done in two steps:
1681 //
1682 // [1] validate_header() - done here.
1683 // [2] validate_shared_path_table - this is done later, because the table is in the RO
1684 //     region of the archive, which is not mapped yet.
1685 bool FileMapInfo::open_as_input() {
1686   assert(CDSConfig::is_using_archive(), "UseSharedSpaces expected.");
1687   assert(Arguments::has_jimage(), "The shared archive file cannot be used with an exploded module build.");
1688 
1689   if (JvmtiExport::should_post_class_file_load_hook() && JvmtiExport::has_early_class_hook_env()) {
1690     // CDS assumes that no classes resolved in vmClasses::resolve_all()
1691     // are replaced at runtime by JVMTI ClassFileLoadHook. All of those classes are resolved
1692     // during the JVMTI "early" stage, so we can still use CDS if
1693     // JvmtiExport::has_early_class_hook_env() is false.
1694     AOTMetaspace::report_loading_error("CDS is disabled because early JVMTI ClassFileLoadHook is in use.");
1695     return false;
1696   }
1697 
1698   if (!open_for_read() || !init_from_file(_fd) || !validate_header()) {
1699     if (_is_static) {
1700       AOTMetaspace::report_loading_error("Loading static archive failed.");
1701       return false;
1702     } else {
1703       AOTMetaspace::report_loading_error("Loading dynamic archive failed.");
1704       if (AutoCreateSharedArchive) {
1705         CDSConfig::enable_dumping_dynamic_archive(_full_path);
1706       }
1707       return false;
1708     }
1709   }
1710 
1711   return true;
1712 }
1713 
1714 bool FileMapInfo::validate_aot_class_linking() {
1715   // These checks need to be done after FileMapInfo::initialize(), which gets called before Universe::heap()
1716   // is available.
1717   if (header()->has_aot_linked_classes()) {
1718     const char* archive_type = CDSConfig::type_of_archive_being_loaded();
1719     CDSConfig::set_has_aot_linked_classes(true);
1720     if (JvmtiExport::should_post_class_file_load_hook()) {
1721       aot_log_error(aot)("%s has aot-linked classes. It cannot be used when JVMTI ClassFileLoadHook is in use.",
1722                      archive_type);
1723       return false;
1724     }
1725     if (JvmtiExport::has_early_vmstart_env()) {
1726       aot_log_error(aot)("%s has aot-linked classes. It cannot be used when JVMTI early vm start is in use.",
1727                      archive_type);
1728       return false;
1729     }
1730     if (!CDSConfig::is_using_full_module_graph()) {
1731       aot_log_error(aot)("%s has aot-linked classes. It cannot be used when archived full module graph is not used.",
1732                      archive_type);
1733       return false;
1734     }
1735 
1736     const char* prop = Arguments::get_property("java.security.manager");
1737     if (prop != nullptr && strcmp(prop, "disallow") != 0) {
1738       aot_log_error(aot)("%s has aot-linked classes. It cannot be used with -Djava.security.manager=%s.",
1739                      archive_type, prop);
1740       return false;
1741     }
1742 
1743 #if INCLUDE_JVMTI
1744     if (Arguments::has_jdwp_agent()) {
1745       aot_log_error(aot)("%s has aot-linked classes. It cannot be used with JDWP agent", archive_type);
1746       return false;
1747     }
1748 #endif
1749   }
1750 
1751   return true;
1752 }
1753 
1754 // The 2 core spaces are RW->RO
1755 FileMapRegion* FileMapInfo::first_core_region() const {
1756   return region_at(AOTMetaspace::rw);
1757 }
1758 
1759 FileMapRegion* FileMapInfo::last_core_region() const {
1760   return region_at(AOTMetaspace::ro);
1761 }
1762 
1763 void FileMapInfo::print(outputStream* st) const {
1764   header()->print(st);
1765   if (!is_static()) {
1766     dynamic_header()->print(st);
1767   }
1768 }
1769 
1770 void FileMapHeader::set_as_offset(char* p, size_t *offset) {
1771   *offset = ArchiveBuilder::current()->any_to_offset((address)p);
1772 }
1773 
1774 int FileMapHeader::compute_crc() {
1775   char* start = (char*)this;
1776   // start computing from the field after _header_size to end of base archive name.
1777   char* buf = (char*)&(_generic_header._header_size) + sizeof(_generic_header._header_size);
1778   size_t sz = header_size() - (buf - start);
1779   int crc = ClassLoader::crc32(0, buf, (jint)sz);
1780   return crc;
1781 }
1782 
1783 // This function should only be called during run time with UseSharedSpaces enabled.
1784 bool FileMapHeader::validate() {
1785   const char* file_type = CDSConfig::type_of_archive_being_loaded();
1786   if (_obj_alignment != ObjectAlignmentInBytes) {
1787     AOTMetaspace::report_loading_error("The %s's ObjectAlignmentInBytes of %d"
1788                                           " does not equal the current ObjectAlignmentInBytes of %d.",
1789                                           file_type, _obj_alignment, ObjectAlignmentInBytes);
1790     return false;
1791   }
1792   if (_compact_strings != CompactStrings) {
1793     AOTMetaspace::report_loading_error("The %s's CompactStrings setting (%s)"
1794                                           " does not equal the current CompactStrings setting (%s).", file_type,
1795                                           _compact_strings ? "enabled" : "disabled",
1796                                           CompactStrings   ? "enabled" : "disabled");
1797     return false;
1798   }
1799   bool jvmci_compiler_is_enabled = CompilerConfig::is_jvmci_compiler_enabled();
1800   CompilerType compiler_type = CompilerConfig::compiler_type();
1801   CompilerType archive_compiler_type = CompilerType(_compiler_type);
1802   // JVMCI compiler does different type profiling settigns and generate
1803   // different code. We can't use archive which was produced
1804   // without it and reverse.
1805   // Only allow mix when JIT compilation is disabled.
1806   // Interpreter is used by default when dumping archive.
1807   bool intepreter_is_used = (archive_compiler_type == CompilerType::compiler_none) ||
1808                             (compiler_type == CompilerType::compiler_none);
1809   if (!intepreter_is_used &&
1810       jvmci_compiler_is_enabled != (archive_compiler_type == CompilerType::compiler_jvmci)) {
1811     AOTMetaspace::report_loading_error("The %s's JIT compiler setting (%s)"
1812                                           " does not equal the current setting (%s).", file_type,
1813                                           compilertype2name(archive_compiler_type), compilertype2name(compiler_type));
1814     return false;
1815   }
1816   if (TrainingData::have_data()) {
1817     if (_type_profile_level != TypeProfileLevel) {
1818       AOTMetaspace::report_loading_error("The %s's TypeProfileLevel setting (%d)"
1819                                             " does not equal the current TypeProfileLevel setting (%d).", file_type,
1820                                             _type_profile_level, TypeProfileLevel);
1821       return false;
1822     }
1823     if (_type_profile_args_limit != TypeProfileArgsLimit) {
1824       AOTMetaspace::report_loading_error("The %s's TypeProfileArgsLimit setting (%d)"
1825                                             " does not equal the current TypeProfileArgsLimit setting (%d).", file_type,
1826                                             _type_profile_args_limit, TypeProfileArgsLimit);
1827       return false;
1828     }
1829     if (_type_profile_parms_limit != TypeProfileParmsLimit) {
1830       AOTMetaspace::report_loading_error("The %s's TypeProfileParamsLimit setting (%d)"
1831                                             " does not equal the current TypeProfileParamsLimit setting (%d).", file_type,
1832                                             _type_profile_args_limit, TypeProfileArgsLimit);
1833       return false;
1834 
1835     }
1836     if (_type_profile_width != TypeProfileWidth) {
1837       AOTMetaspace::report_loading_error("The %s's TypeProfileWidth setting (%d)"
1838                                             " does not equal the current TypeProfileWidth setting (%d).", file_type,
1839                                             (int)_type_profile_width, (int)TypeProfileWidth);
1840       return false;
1841 
1842     }
1843     if (_bci_profile_width != BciProfileWidth) {
1844       AOTMetaspace::report_loading_error("The %s's BciProfileWidth setting (%d)"
1845                                             " does not equal the current BciProfileWidth setting (%d).", file_type,
1846                                             (int)_bci_profile_width, (int)BciProfileWidth);
1847       return false;
1848     }
1849     if (_type_profile_casts != TypeProfileCasts) {
1850       AOTMetaspace::report_loading_error("The %s's TypeProfileCasts setting (%s)"
1851                                             " does not equal the current TypeProfileCasts setting (%s).", file_type,
1852                                             _type_profile_casts ? "enabled" : "disabled",
1853                                             TypeProfileCasts    ? "enabled" : "disabled");
1854 
1855       return false;
1856 
1857     }
1858     if (_profile_traps != ProfileTraps) {
1859       AOTMetaspace::report_loading_error("The %s's ProfileTraps setting (%s)"
1860                                             " does not equal the current ProfileTraps setting (%s).", file_type,
1861                                             _profile_traps ? "enabled" : "disabled",
1862                                             ProfileTraps   ? "enabled" : "disabled");
1863 
1864       return false;
1865     }
1866     if (_spec_trap_limit_extra_entries != SpecTrapLimitExtraEntries) {
1867       AOTMetaspace::report_loading_error("The %s's SpecTrapLimitExtraEntries setting (%d)"
1868                                             " does not equal the current SpecTrapLimitExtraEntries setting (%d).", file_type,
1869                                             _spec_trap_limit_extra_entries, SpecTrapLimitExtraEntries);
1870       return false;
1871 
1872     }
1873   }
1874 
1875   // This must be done after header validation because it might change the
1876   // header data
1877   const char* prop = Arguments::get_property("java.system.class.loader");
1878   if (prop != nullptr) {
1879     if (has_aot_linked_classes()) {
1880       AOTMetaspace::report_loading_error("%s has aot-linked classes. It cannot be used when the "
1881                                             "java.system.class.loader property is specified.",
1882                                             CDSConfig::type_of_archive_being_loaded());
1883       return false;
1884     }
1885     aot_log_warning(aot)("Archived non-system classes are disabled because the "
1886             "java.system.class.loader property is specified (value = \"%s\"). "
1887             "To use archived non-system classes, this property must not be set", prop);
1888     _has_platform_or_app_classes = false;
1889   }
1890 
1891 
1892   if (!_verify_local && BytecodeVerificationLocal) {
1893     //  we cannot load boot classes, so there's no point of using the CDS archive
1894     AOTMetaspace::report_loading_error("The %s's BytecodeVerificationLocal setting (%s)"
1895                                           " does not equal the current BytecodeVerificationLocal setting (%s).", file_type,
1896                                           _verify_local ? "enabled" : "disabled",
1897                                           BytecodeVerificationLocal ? "enabled" : "disabled");
1898     return false;
1899   }
1900 
1901   // For backwards compatibility, we don't check the BytecodeVerificationRemote setting
1902   // if the archive only contains system classes.
1903   if (_has_platform_or_app_classes
1904       && !_verify_remote // we didn't verify the archived platform/app classes
1905       && BytecodeVerificationRemote) { // but we want to verify all loaded platform/app classes
1906     aot_log_info(aot)("The %s was created with less restrictive "
1907                                "verification setting than the current setting.", file_type);
1908     // Pretend that we didn't have any archived platform/app classes, so they won't be loaded
1909     // by SystemDictionaryShared.
1910     _has_platform_or_app_classes = false;
1911   }
1912 
1913   aot_log_info(aot)("The %s was created with UseCompressedOops = %d, UseCompressedClassPointers = %d, UseCompactObjectHeaders = %d",
1914                           file_type, compressed_oops(), compressed_class_pointers(), compact_headers());
1915   if (compressed_oops() != UseCompressedOops || compressed_class_pointers() != UseCompressedClassPointers) {
1916     aot_log_warning(aot)("Unable to use %s.\nThe saved state of UseCompressedOops and UseCompressedClassPointers is "
1917                                "different from runtime, CDS will be disabled.", file_type);
1918     return false;
1919   }
1920 
1921   if (compact_headers() != UseCompactObjectHeaders) {
1922     aot_log_warning(aot)("Unable to use %s.\nThe %s's UseCompactObjectHeaders setting (%s)"
1923                      " does not equal the current UseCompactObjectHeaders setting (%s).", file_type, file_type,
1924                      _compact_headers          ? "enabled" : "disabled",
1925                      UseCompactObjectHeaders   ? "enabled" : "disabled");
1926     return false;
1927   }
1928 
1929   if (!_use_optimized_module_handling && !CDSConfig::is_dumping_final_static_archive()) {
1930     CDSConfig::stop_using_optimized_module_handling();
1931     aot_log_info(aot)("optimized module handling: disabled because archive was created without optimized module handling");
1932   }
1933 
1934   if (is_static()) {
1935     // Only the static archive can contain the full module graph.
1936     if (!_has_full_module_graph) {
1937       CDSConfig::stop_using_full_module_graph("archive was created without full module graph");
1938     }
1939   }
1940 
1941   return true;
1942 }
1943 
1944 bool FileMapInfo::validate_header() {
1945   if (!header()->validate()) {
1946     return false;
1947   }
1948   if (_is_static) {
1949     return true;
1950   } else {
1951     return DynamicArchive::validate(this);
1952   }
1953 }
1954 
1955 #if INCLUDE_JVMTI
1956 ClassPathEntry** FileMapInfo::_classpath_entries_for_jvmti = nullptr;
1957 
1958 ClassPathEntry* FileMapInfo::get_classpath_entry_for_jvmti(int i, TRAPS) {
1959   if (i == 0) {
1960     // index 0 corresponds to the ClassPathImageEntry which is a globally shared object
1961     // and should never be deleted.
1962     return ClassLoader::get_jrt_entry();
1963   }
1964   ClassPathEntry* ent = _classpath_entries_for_jvmti[i];
1965   if (ent == nullptr) {
1966     const AOTClassLocation* cl = AOTClassLocationConfig::runtime()->class_location_at(i);
1967     const char* path = cl->path();
1968     struct stat st;
1969     if (os::stat(path, &st) != 0) {
1970       char *msg = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, strlen(path) + 128);
1971       jio_snprintf(msg, strlen(path) + 127, "error in finding JAR file %s", path);
1972       THROW_MSG_(vmSymbols::java_io_IOException(), msg, nullptr);
1973     } else {
1974       ent = ClassLoader::create_class_path_entry(THREAD, path, &st);
1975       if (ent == nullptr) {
1976         char *msg = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, strlen(path) + 128);
1977         jio_snprintf(msg, strlen(path) + 127, "error in opening JAR file %s", path);
1978         THROW_MSG_(vmSymbols::java_io_IOException(), msg, nullptr);
1979       }
1980     }
1981 
1982     MutexLocker mu(THREAD, CDSClassFileStream_lock);
1983     if (_classpath_entries_for_jvmti[i] == nullptr) {
1984       _classpath_entries_for_jvmti[i] = ent;
1985     } else {
1986       // Another thread has beat me to creating this entry
1987       delete ent;
1988       ent = _classpath_entries_for_jvmti[i];
1989     }
1990   }
1991 
1992   return ent;
1993 }
1994 
1995 ClassFileStream* FileMapInfo::open_stream_for_jvmti(InstanceKlass* ik, Handle class_loader, TRAPS) {
1996   int path_index = ik->shared_classpath_index();
1997   assert(path_index >= 0, "should be called for shared built-in classes only");
1998   assert(path_index < AOTClassLocationConfig::runtime()->length(), "sanity");
1999 
2000   ClassPathEntry* cpe = get_classpath_entry_for_jvmti(path_index, CHECK_NULL);
2001   assert(cpe != nullptr, "must be");
2002 
2003   Symbol* name = ik->name();
2004   const char* const class_name = name->as_C_string();
2005   const char* const file_name = ClassLoader::file_name_for_class_name(class_name,
2006                                                                       name->utf8_length());
2007   ClassLoaderData* loader_data = ClassLoaderData::class_loader_data(class_loader());
2008   const AOTClassLocation* cl = AOTClassLocationConfig::runtime()->class_location_at(path_index);
2009   ClassFileStream* cfs;
2010   if (class_loader() != nullptr && cl->is_multi_release_jar()) {
2011     // This class was loaded from a multi-release JAR file during dump time. The
2012     // process for finding its classfile is complex. Let's defer to the Java code
2013     // in java.lang.ClassLoader.
2014     cfs = get_stream_from_class_loader(class_loader, cpe, file_name, CHECK_NULL);
2015   } else {
2016     cfs = cpe->open_stream_for_loader(THREAD, file_name, loader_data);
2017   }
2018   assert(cfs != nullptr, "must be able to read the classfile data of shared classes for built-in loaders.");
2019   log_debug(aot, jvmti)("classfile data for %s [%d: %s] = %d bytes", class_name, path_index,
2020                         cfs->source(), cfs->length());
2021   return cfs;
2022 }
2023 
2024 ClassFileStream* FileMapInfo::get_stream_from_class_loader(Handle class_loader,
2025                                                            ClassPathEntry* cpe,
2026                                                            const char* file_name,
2027                                                            TRAPS) {
2028   JavaValue result(T_OBJECT);
2029   oop class_name = java_lang_String::create_oop_from_str(file_name, THREAD);
2030   Handle h_class_name = Handle(THREAD, class_name);
2031 
2032   // byte[] ClassLoader.getResourceAsByteArray(String name)
2033   JavaCalls::call_virtual(&result,
2034                           class_loader,
2035                           vmClasses::ClassLoader_klass(),
2036                           vmSymbols::getResourceAsByteArray_name(),
2037                           vmSymbols::getResourceAsByteArray_signature(),
2038                           h_class_name,
2039                           CHECK_NULL);
2040   assert(result.get_type() == T_OBJECT, "just checking");
2041   oop obj = result.get_oop();
2042   assert(obj != nullptr, "ClassLoader.getResourceAsByteArray should not return null");
2043 
2044   // copy from byte[] to a buffer
2045   typeArrayOop ba = typeArrayOop(obj);
2046   jint len = ba->length();
2047   u1* buffer = NEW_RESOURCE_ARRAY(u1, len);
2048   ArrayAccess<>::arraycopy_to_native<>(ba, typeArrayOopDesc::element_offset<jbyte>(0), buffer, len);
2049 
2050   return new ClassFileStream(buffer, len, cpe->name());
2051 }
2052 #endif