filemap.cpp revision 13370:731370f39fcd
1/* 2 * Copyright (c) 2003, 2017, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25#include "precompiled.hpp" 26#include "classfile/classLoader.hpp" 27#include "classfile/compactHashtable.inline.hpp" 28#include "classfile/sharedClassUtil.hpp" 29#include "classfile/stringTable.hpp" 30#include "classfile/symbolTable.hpp" 31#include "classfile/systemDictionaryShared.hpp" 32#include "classfile/altHashing.hpp" 33#if INCLUDE_ALL_GCS 34#include "gc/g1/g1CollectedHeap.hpp" 35#endif 36#include "logging/log.hpp" 37#include "logging/logStream.hpp" 38#include "logging/logMessage.hpp" 39#include "memory/filemap.hpp" 40#include "memory/metadataFactory.hpp" 41#include "memory/metaspaceClosure.hpp" 42#include "memory/metaspaceShared.hpp" 43#include "memory/oopFactory.hpp" 44#include "oops/objArrayOop.hpp" 45#include "prims/jvm.h" 46#include "prims/jvmtiExport.hpp" 47#include "runtime/arguments.hpp" 48#include "runtime/java.hpp" 49#include "runtime/os.hpp" 50#include "runtime/vm_version.hpp" 51#include "services/memTracker.hpp" 52#include "utilities/align.hpp" 53#include "utilities/defaultStream.hpp" 54 55# include <sys/stat.h> 56# include <errno.h> 57 58#ifndef O_BINARY // if defined (Win32) use binary files. 59#define O_BINARY 0 // otherwise do nothing. 60#endif 61 62extern address JVM_FunctionAtStart(); 63extern address JVM_FunctionAtEnd(); 64 65// Complain and stop. All error conditions occurring during the writing of 66// an archive file should stop the process. Unrecoverable errors during 67// the reading of the archive file should stop the process. 68 69static void fail(const char *msg, va_list ap) { 70 // This occurs very early during initialization: tty is not initialized. 71 jio_fprintf(defaultStream::error_stream(), 72 "An error has occurred while processing the" 73 " shared archive file.\n"); 74 jio_vfprintf(defaultStream::error_stream(), msg, ap); 75 jio_fprintf(defaultStream::error_stream(), "\n"); 76 // Do not change the text of the below message because some tests check for it. 77 vm_exit_during_initialization("Unable to use shared archive.", NULL); 78} 79 80 81void FileMapInfo::fail_stop(const char *msg, ...) { 82 va_list ap; 83 va_start(ap, msg); 84 fail(msg, ap); // Never returns. 85 va_end(ap); // for completeness. 86} 87 88 89// Complain and continue. Recoverable errors during the reading of the 90// archive file may continue (with sharing disabled). 91// 92// If we continue, then disable shared spaces and close the file. 93 94void FileMapInfo::fail_continue(const char *msg, ...) { 95 va_list ap; 96 va_start(ap, msg); 97 MetaspaceShared::set_archive_loading_failed(); 98 if (PrintSharedArchiveAndExit && _validating_classpath_entry_table) { 99 // If we are doing PrintSharedArchiveAndExit and some of the classpath entries 100 // do not validate, we can still continue "limping" to validate the remaining 101 // entries. No need to quit. 102 tty->print("["); 103 tty->vprint(msg, ap); 104 tty->print_cr("]"); 105 } else { 106 if (RequireSharedSpaces) { 107 fail(msg, ap); 108 } else { 109 if (log_is_enabled(Info, cds)) { 110 ResourceMark rm; 111 LogStream ls(Log(cds)::info()); 112 ls.print("UseSharedSpaces: "); 113 ls.vprint_cr(msg, ap); 114 } 115 } 116 UseSharedSpaces = false; 117 assert(current_info() != NULL, "singleton must be registered"); 118 current_info()->close(); 119 } 120 va_end(ap); 121} 122 123// Fill in the fileMapInfo structure with data about this VM instance. 124 125// This method copies the vm version info into header_version. If the version is too 126// long then a truncated version, which has a hash code appended to it, is copied. 127// 128// Using a template enables this method to verify that header_version is an array of 129// length JVM_IDENT_MAX. This ensures that the code that writes to the CDS file and 130// the code that reads the CDS file will both use the same size buffer. Hence, will 131// use identical truncation. This is necessary for matching of truncated versions. 132template <int N> static void get_header_version(char (&header_version) [N]) { 133 assert(N == JVM_IDENT_MAX, "Bad header_version size"); 134 135 const char *vm_version = VM_Version::internal_vm_info_string(); 136 const int version_len = (int)strlen(vm_version); 137 138 if (version_len < (JVM_IDENT_MAX-1)) { 139 strcpy(header_version, vm_version); 140 141 } else { 142 // Get the hash value. Use a static seed because the hash needs to return the same 143 // value over multiple jvm invocations. 144 unsigned int hash = AltHashing::murmur3_32(8191, (const jbyte*)vm_version, version_len); 145 146 // Truncate the ident, saving room for the 8 hex character hash value. 147 strncpy(header_version, vm_version, JVM_IDENT_MAX-9); 148 149 // Append the hash code as eight hex digits. 150 sprintf(&header_version[JVM_IDENT_MAX-9], "%08x", hash); 151 header_version[JVM_IDENT_MAX-1] = 0; // Null terminate. 152 } 153} 154 155FileMapInfo::FileMapInfo() { 156 assert(_current_info == NULL, "must be singleton"); // not thread safe 157 _current_info = this; 158 memset((void*)this, 0, sizeof(FileMapInfo)); 159 _file_offset = 0; 160 _file_open = false; 161 _header = SharedClassUtil::allocate_file_map_header(); 162 _header->_version = _invalid_version; 163} 164 165FileMapInfo::~FileMapInfo() { 166 assert(_current_info == this, "must be singleton"); // not thread safe 167 _current_info = NULL; 168} 169 170void FileMapInfo::populate_header(size_t alignment) { 171 _header->populate(this, alignment); 172} 173 174size_t FileMapInfo::FileMapHeader::data_size() { 175 return SharedClassUtil::file_map_header_size() - sizeof(FileMapInfo::FileMapHeaderBase); 176} 177 178void FileMapInfo::FileMapHeader::populate(FileMapInfo* mapinfo, size_t alignment) { 179 _magic = 0xf00baba2; 180 _version = _current_version; 181 _alignment = alignment; 182 _obj_alignment = ObjectAlignmentInBytes; 183 _compact_strings = CompactStrings; 184 _narrow_oop_mode = Universe::narrow_oop_mode(); 185 _narrow_oop_shift = Universe::narrow_oop_shift(); 186 _max_heap_size = MaxHeapSize; 187 _narrow_klass_base = Universe::narrow_klass_base(); 188 _narrow_klass_shift = Universe::narrow_klass_shift(); 189 _classpath_entry_table_size = mapinfo->_classpath_entry_table_size; 190 _classpath_entry_table = mapinfo->_classpath_entry_table; 191 _classpath_entry_size = mapinfo->_classpath_entry_size; 192 193 // The following fields are for sanity checks for whether this archive 194 // will function correctly with this JVM and the bootclasspath it's 195 // invoked with. 196 197 // JVM version string ... changes on each build. 198 get_header_version(_jvm_ident); 199} 200 201void SharedClassPathEntry::init(const char* name, TRAPS) { 202 _timestamp = 0; 203 _filesize = 0; 204 205 struct stat st; 206 if (os::stat(name, &st) == 0) { 207 if ((st.st_mode & S_IFMT) == S_IFDIR) { 208 if (!os::dir_is_empty(name)) { 209 ClassLoader::exit_with_path_failure( 210 "Cannot have non-empty directory in archived classpaths", name); 211 } 212 _is_dir = true; 213 } else { 214 _is_dir = false; 215 _timestamp = st.st_mtime; 216 _filesize = st.st_size; 217 } 218 } else { 219 // The file/dir must exist, or it would not have been added 220 // into ClassLoader::classpath_entry(). 221 // 222 // If we can't access a jar file in the boot path, then we can't 223 // make assumptions about where classes get loaded from. 224 FileMapInfo::fail_stop("Unable to open file %s.", name); 225 } 226 227 size_t len = strlen(name) + 1; 228 _name = MetadataFactory::new_array<char>(ClassLoaderData::the_null_class_loader_data(), (int)len, THREAD); 229 strcpy(_name->data(), name); 230} 231 232bool SharedClassPathEntry::validate() { 233 struct stat st; 234 const char* name = this->name(); 235 bool ok = true; 236 log_info(class, path)("checking shared classpath entry: %s", name); 237 if (os::stat(name, &st) != 0) { 238 FileMapInfo::fail_continue("Required classpath entry does not exist: %s", name); 239 ok = false; 240 } else if (is_dir()) { 241 if (!os::dir_is_empty(name)) { 242 FileMapInfo::fail_continue("directory is not empty: %s", name); 243 ok = false; 244 } 245 } else if (is_jar_or_bootimage()) { 246 if (_timestamp != st.st_mtime || 247 _filesize != st.st_size) { 248 ok = false; 249 if (PrintSharedArchiveAndExit) { 250 FileMapInfo::fail_continue(_timestamp != st.st_mtime ? 251 "Timestamp mismatch" : 252 "File size mismatch"); 253 } else { 254 FileMapInfo::fail_continue("A jar/jimage file is not the one used while building" 255 " the shared archive file: %s", name); 256 } 257 } 258 } 259 return ok; 260} 261 262void SharedClassPathEntry::metaspace_pointers_do(MetaspaceClosure* it) { 263 it->push(&_name); 264 it->push(&_manifest); 265} 266 267void FileMapInfo::allocate_classpath_entry_table() { 268 Thread* THREAD = Thread::current(); 269 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data(); 270 size_t entry_size = SharedClassUtil::shared_class_path_entry_size(); // assert ( should be 8 byte aligned??) 271 int num_entries = ClassLoader::number_of_classpath_entries(); 272 size_t bytes = entry_size * num_entries; 273 274 _classpath_entry_table = MetadataFactory::new_array<u8>(loader_data, (int)(bytes + 7 / 8), THREAD); 275 _classpath_entry_table_size = num_entries; 276 _classpath_entry_size = entry_size; 277 278 assert(ClassLoader::get_jrt_entry() != NULL, 279 "No modular java runtime image present when allocating the CDS classpath entry table"); 280 281 for (int i=0; i<num_entries; i++) { 282 ClassPathEntry *cpe = ClassLoader::classpath_entry(i); 283 const char* type = ((i == 0) ? "jrt" : (cpe->is_jar_file() ? "jar" : "dir")); 284 285 log_info(class, path)("add main shared path (%s) %s", type, cpe->name()); 286 SharedClassPathEntry* ent = shared_classpath(i); 287 ent->init(cpe->name(), THREAD); 288 289 if (i > 0) { // No need to do jimage. 290 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error. 291 SharedClassUtil::update_shared_classpath(cpe, ent, THREAD); 292 } 293 } 294} 295 296bool FileMapInfo::validate_classpath_entry_table() { 297 _validating_classpath_entry_table = true; 298 299 int count = _header->_classpath_entry_table_size; 300 301 _classpath_entry_table = _header->_classpath_entry_table; 302 _classpath_entry_size = _header->_classpath_entry_size; 303 _classpath_entry_table_size = _header->_classpath_entry_table_size; 304 305 for (int i=0; i<count; i++) { 306 if (shared_classpath(i)->validate()) { 307 log_info(class, path)("ok"); 308 } else if (!PrintSharedArchiveAndExit) { 309 _validating_classpath_entry_table = false; 310 _classpath_entry_table = NULL; 311 _classpath_entry_table_size = 0; 312 return false; 313 } 314 } 315 316 _validating_classpath_entry_table = false; 317 return true; 318} 319 320 321// Read the FileMapInfo information from the file. 322 323bool FileMapInfo::init_from_file(int fd) { 324 size_t sz = _header->data_size(); 325 char* addr = _header->data(); 326 size_t n = os::read(fd, addr, (unsigned int)sz); 327 if (n != sz) { 328 fail_continue("Unable to read the file header."); 329 return false; 330 } 331 if (_header->_version != current_version()) { 332 fail_continue("The shared archive file has the wrong version."); 333 return false; 334 } 335 _file_offset = (long)n; 336 337 size_t info_size = _header->_paths_misc_info_size; 338 _paths_misc_info = NEW_C_HEAP_ARRAY_RETURN_NULL(char, info_size, mtClass); 339 if (_paths_misc_info == NULL) { 340 fail_continue("Unable to read the file header."); 341 return false; 342 } 343 n = os::read(fd, _paths_misc_info, (unsigned int)info_size); 344 if (n != info_size) { 345 fail_continue("Unable to read the shared path info header."); 346 FREE_C_HEAP_ARRAY(char, _paths_misc_info); 347 _paths_misc_info = NULL; 348 return false; 349 } 350 351 size_t len = lseek(fd, 0, SEEK_END); 352 struct FileMapInfo::FileMapHeader::space_info* si = 353 &_header->_space[MetaspaceShared::last_valid_region]; 354 if (si->_file_offset >= len || len - si->_file_offset < si->_used) { 355 fail_continue("The shared archive file has been truncated."); 356 return false; 357 } 358 359 _file_offset += (long)n; 360 return true; 361} 362 363 364// Read the FileMapInfo information from the file. 365bool FileMapInfo::open_for_read() { 366 _full_path = Arguments::GetSharedArchivePath(); 367 int fd = open(_full_path, O_RDONLY | O_BINARY, 0); 368 if (fd < 0) { 369 if (errno == ENOENT) { 370 // Not locating the shared archive is ok. 371 fail_continue("Specified shared archive not found."); 372 } else { 373 fail_continue("Failed to open shared archive file (%s).", 374 os::strerror(errno)); 375 } 376 return false; 377 } 378 379 _fd = fd; 380 _file_open = true; 381 return true; 382} 383 384 385// Write the FileMapInfo information to the file. 386 387void FileMapInfo::open_for_write() { 388 _full_path = Arguments::GetSharedArchivePath(); 389 if (log_is_enabled(Info, cds)) { 390 ResourceMark rm; 391 LogMessage(cds) msg; 392 stringStream info_stream; 393 info_stream.print_cr("Dumping shared data to file: "); 394 info_stream.print_cr(" %s", _full_path); 395 msg.info("%s", info_stream.as_string()); 396 } 397 398#ifdef _WINDOWS // On Windows, need WRITE permission to remove the file. 399 chmod(_full_path, _S_IREAD | _S_IWRITE); 400#endif 401 402 // Use remove() to delete the existing file because, on Unix, this will 403 // allow processes that have it open continued access to the file. 404 remove(_full_path); 405 int fd = open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444); 406 if (fd < 0) { 407 fail_stop("Unable to create shared archive file %s: (%s).", _full_path, 408 os::strerror(errno)); 409 } 410 _fd = fd; 411 _file_offset = 0; 412 _file_open = true; 413} 414 415 416// Write the header to the file, seek to the next allocation boundary. 417 418void FileMapInfo::write_header() { 419 int info_size = ClassLoader::get_shared_paths_misc_info_size(); 420 421 _header->_paths_misc_info_size = info_size; 422 423 align_file_position(); 424 size_t sz = _header->data_size(); 425 char* addr = _header->data(); 426 write_bytes(addr, (int)sz); // skip the C++ vtable 427 write_bytes(ClassLoader::get_shared_paths_misc_info(), info_size); 428 align_file_position(); 429} 430 431 432// Dump region to file. 433 434void FileMapInfo::write_region(int region, char* base, size_t size, 435 bool read_only, bool allow_exec) { 436 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[region]; 437 438 if (_file_open) { 439 guarantee(si->_file_offset == _file_offset, "file offset mismatch."); 440 log_info(cds)("Shared file region %d: " SIZE_FORMAT_HEX_W(08) 441 " bytes, addr " INTPTR_FORMAT " file offset " SIZE_FORMAT_HEX_W(08), 442 region, size, p2i(base), _file_offset); 443 } else { 444 si->_file_offset = _file_offset; 445 } 446 if (MetaspaceShared::is_string_region(region)) { 447 assert((base - (char*)Universe::narrow_oop_base()) % HeapWordSize == 0, "Sanity"); 448 if (base != NULL) { 449 si->_addr._offset = (intx)oopDesc::encode_heap_oop_not_null((oop)base); 450 } else { 451 si->_addr._offset = 0; 452 } 453 } else { 454 si->_addr._base = base; 455 } 456 si->_used = size; 457 si->_read_only = read_only; 458 si->_allow_exec = allow_exec; 459 si->_crc = ClassLoader::crc32(0, base, (jint)size); 460 write_bytes_aligned(base, (int)size); 461} 462 463// Write the string space. The string space contains one or multiple GC(G1) regions. 464// When the total string space size is smaller than one GC region of the dump time, 465// only one string region is used for shared strings. 466// 467// If the total string space size is bigger than one GC region, there would be more 468// than one GC regions allocated for shared strings. The first/bottom GC region might 469// be a partial GC region with the empty portion at the higher address within that region. 470// The non-empty portion of the first region is written into the archive as one string 471// region. The rest are consecutive full GC regions if they exist, which can be written 472// out in one chunk as another string region. 473// 474// Here's the mapping from (GrowableArray<MemRegion> *regions) -> (metaspace string regions). 475// + We have 1 or more heap regions: r0, r1, r2 ..... rn 476// + We have 2 metaspace string regions: s0 and s1 477// 478// If there's a single heap region (r0), then s0 == r0, and s1 is empty. 479// Otherwise: 480// 481// "X" represented space that's occupied by heap objects. 482// "_" represented unused spaced in the heap region. 483// 484// 485// |r0 | r1 | r2 | ...... | rn | 486// |XXXXXX|__ |XXXXX|XXXX|XXXXXXXX|XXXX| 487// |<-s0->| |<- s1 ----------------->| 488// ^^^ 489// | 490// +-- unmapped space 491void FileMapInfo::write_string_regions(GrowableArray<MemRegion> *regions, 492 char** st0_start, char** st0_top, char** st0_end, 493 char** st1_start, char** st1_top, char** st1_end) { 494 *st0_start = *st0_top = *st0_end = NULL; 495 *st1_start = *st1_top = *st1_end = NULL; 496 497 assert(MetaspaceShared::max_strings == 2, "this loop doesn't work for any other value"); 498 for (int i = MetaspaceShared::first_string; 499 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) { 500 char* start = NULL; 501 size_t size = 0; 502 int len = regions->length(); 503 if (len > 0) { 504 if (i == MetaspaceShared::first_string) { 505 MemRegion first = regions->first(); 506 start = (char*)first.start(); 507 size = first.byte_size(); 508 *st0_start = start; 509 *st0_top = start + size; 510 if (len > 1) { 511 *st0_end = (char*)regions->at(1).start(); 512 } else { 513 *st0_end = start + size; 514 } 515 } else { 516 assert(i == MetaspaceShared::first_string + 1, "must be"); 517 if (len > 1) { 518 start = (char*)regions->at(1).start(); 519 size = (char*)regions->at(len - 1).end() - start; 520 *st1_start = start; 521 *st1_top = start + size; 522 *st1_end = start + size; 523 } 524 } 525 } 526 log_info(cds)("String region %d " INTPTR_FORMAT " - " INTPTR_FORMAT " = " SIZE_FORMAT_W(8) " bytes", 527 i, p2i(start), p2i(start + size), size); 528 write_region(i, start, size, false, false); 529 } 530} 531 532 533// Dump bytes to file -- at the current file position. 534 535void FileMapInfo::write_bytes(const void* buffer, int nbytes) { 536 if (_file_open) { 537 int n = ::write(_fd, buffer, nbytes); 538 if (n != nbytes) { 539 // It is dangerous to leave the corrupted shared archive file around, 540 // close and remove the file. See bug 6372906. 541 close(); 542 remove(_full_path); 543 fail_stop("Unable to write to shared archive file."); 544 } 545 } 546 _file_offset += nbytes; 547} 548 549 550// Align file position to an allocation unit boundary. 551 552void FileMapInfo::align_file_position() { 553 size_t new_file_offset = align_up(_file_offset, 554 os::vm_allocation_granularity()); 555 if (new_file_offset != _file_offset) { 556 _file_offset = new_file_offset; 557 if (_file_open) { 558 // Seek one byte back from the target and write a byte to insure 559 // that the written file is the correct length. 560 _file_offset -= 1; 561 if (lseek(_fd, (long)_file_offset, SEEK_SET) < 0) { 562 fail_stop("Unable to seek."); 563 } 564 char zero = 0; 565 write_bytes(&zero, 1); 566 } 567 } 568} 569 570 571// Dump bytes to file -- at the current file position. 572 573void FileMapInfo::write_bytes_aligned(const void* buffer, int nbytes) { 574 align_file_position(); 575 write_bytes(buffer, nbytes); 576 align_file_position(); 577} 578 579 580// Close the shared archive file. This does NOT unmap mapped regions. 581 582void FileMapInfo::close() { 583 if (_file_open) { 584 if (::close(_fd) < 0) { 585 fail_stop("Unable to close the shared archive file."); 586 } 587 _file_open = false; 588 _fd = -1; 589 } 590} 591 592 593// JVM/TI RedefineClasses() support: 594// Remap the shared readonly space to shared readwrite, private. 595bool FileMapInfo::remap_shared_readonly_as_readwrite() { 596 int idx = MetaspaceShared::ro; 597 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[idx]; 598 if (!si->_read_only) { 599 // the space is already readwrite so we are done 600 return true; 601 } 602 size_t used = si->_used; 603 size_t size = align_up(used, os::vm_allocation_granularity()); 604 if (!open_for_read()) { 605 return false; 606 } 607 char *addr = _header->region_addr(idx); 608 char *base = os::remap_memory(_fd, _full_path, si->_file_offset, 609 addr, size, false /* !read_only */, 610 si->_allow_exec); 611 close(); 612 if (base == NULL) { 613 fail_continue("Unable to remap shared readonly space (errno=%d).", errno); 614 return false; 615 } 616 if (base != addr) { 617 fail_continue("Unable to remap shared readonly space at required address."); 618 return false; 619 } 620 si->_read_only = false; 621 return true; 622} 623 624// Map the whole region at once, assumed to be allocated contiguously. 625ReservedSpace FileMapInfo::reserve_shared_memory() { 626 char* requested_addr = _header->region_addr(0); 627 size_t size = FileMapInfo::core_spaces_size(); 628 629 // Reserve the space first, then map otherwise map will go right over some 630 // other reserved memory (like the code cache). 631 ReservedSpace rs(size, os::vm_allocation_granularity(), false, requested_addr); 632 if (!rs.is_reserved()) { 633 fail_continue("Unable to reserve shared space at required address " 634 INTPTR_FORMAT, p2i(requested_addr)); 635 return rs; 636 } 637 // the reserved virtual memory is for mapping class data sharing archive 638 MemTracker::record_virtual_memory_type((address)rs.base(), mtClassShared); 639 640 return rs; 641} 642 643// Memory map a region in the address space. 644static const char* shared_region_name[] = { "ReadOnly", "ReadWrite", "MiscData", "MiscCode", 645 "String1", "String2", "OptionalData" }; 646 647char* FileMapInfo::map_region(int i) { 648 assert(!MetaspaceShared::is_string_region(i), "sanity"); 649 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i]; 650 size_t used = si->_used; 651 size_t alignment = os::vm_allocation_granularity(); 652 size_t size = align_up(used, alignment); 653 char *requested_addr = _header->region_addr(i); 654 655 // If a tool agent is in use (debugging enabled), we must map the address space RW 656 if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space()) { 657 si->_read_only = false; 658 } 659 660 // map the contents of the CDS archive in this memory 661 char *base = os::map_memory(_fd, _full_path, si->_file_offset, 662 requested_addr, size, si->_read_only, 663 si->_allow_exec); 664 if (base == NULL || base != requested_addr) { 665 fail_continue("Unable to map %s shared space at required address.", shared_region_name[i]); 666 return NULL; 667 } 668#ifdef _WINDOWS 669 // This call is Windows-only because the memory_type gets recorded for the other platforms 670 // in method FileMapInfo::reserve_shared_memory(), which is not called on Windows. 671 MemTracker::record_virtual_memory_type((address)base, mtClassShared); 672#endif 673 674 return base; 675} 676 677static MemRegion *string_ranges = NULL; 678static int num_ranges = 0; 679bool FileMapInfo::map_string_regions() { 680#if INCLUDE_ALL_GCS 681 if (UseG1GC && UseCompressedOops && UseCompressedClassPointers) { 682 // Check that all the narrow oop and klass encodings match the archive 683 if (narrow_oop_mode() != Universe::narrow_oop_mode() || 684 narrow_oop_shift() != Universe::narrow_oop_shift() || 685 narrow_klass_base() != Universe::narrow_klass_base() || 686 narrow_klass_shift() != Universe::narrow_klass_shift()) { 687 if (log_is_enabled(Info, cds) && _header->_space[MetaspaceShared::first_string]._used > 0) { 688 log_info(cds)("Shared string data from the CDS archive is being ignored. " 689 "The current CompressedOops/CompressedClassPointers encoding differs from " 690 "that archived due to heap size change. The archive was dumped using max heap " 691 "size " UINTX_FORMAT "M.", max_heap_size()/M); 692 } 693 } else { 694 string_ranges = new MemRegion[MetaspaceShared::max_strings]; 695 struct FileMapInfo::FileMapHeader::space_info* si; 696 697 for (int i = MetaspaceShared::first_string; 698 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) { 699 si = &_header->_space[i]; 700 size_t used = si->_used; 701 if (used > 0) { 702 size_t size = used; 703 char* requested_addr = (char*)((void*)oopDesc::decode_heap_oop_not_null( 704 (narrowOop)si->_addr._offset)); 705 string_ranges[num_ranges] = MemRegion((HeapWord*)requested_addr, size / HeapWordSize); 706 num_ranges ++; 707 } 708 } 709 710 if (num_ranges == 0) { 711 StringTable::ignore_shared_strings(true); 712 return true; // no shared string data 713 } 714 715 // Check that ranges are within the java heap 716 if (!G1CollectedHeap::heap()->check_archive_addresses(string_ranges, num_ranges)) { 717 fail_continue("Unable to allocate shared string space: range is not " 718 "within java heap."); 719 return false; 720 } 721 722 // allocate from java heap 723 if (!G1CollectedHeap::heap()->alloc_archive_regions(string_ranges, num_ranges)) { 724 fail_continue("Unable to allocate shared string space: range is " 725 "already in use."); 726 return false; 727 } 728 729 // Map the string data. No need to call MemTracker::record_virtual_memory_type() 730 // for mapped string regions as they are part of the reserved java heap, which 731 // is already recorded. 732 for (int i = 0; i < num_ranges; i++) { 733 si = &_header->_space[MetaspaceShared::first_string + i]; 734 char* addr = (char*)string_ranges[i].start(); 735 char* base = os::map_memory(_fd, _full_path, si->_file_offset, 736 addr, string_ranges[i].byte_size(), si->_read_only, 737 si->_allow_exec); 738 if (base == NULL || base != addr) { 739 // dealloc the string regions from java heap 740 dealloc_string_regions(); 741 fail_continue("Unable to map shared string space at required address."); 742 return false; 743 } 744 } 745 746 if (!verify_string_regions()) { 747 // dealloc the string regions from java heap 748 dealloc_string_regions(); 749 fail_continue("Shared string regions are corrupt"); 750 return false; 751 } 752 753 // the shared string data is mapped successfully 754 return true; 755 } 756 } else { 757 if (log_is_enabled(Info, cds) && _header->_space[MetaspaceShared::first_string]._used > 0) { 758 log_info(cds)("Shared string data from the CDS archive is being ignored. UseG1GC, " 759 "UseCompressedOops and UseCompressedClassPointers are required."); 760 } 761 } 762 763 // if we get here, the shared string data is not mapped 764 assert(string_ranges == NULL && num_ranges == 0, "sanity"); 765 StringTable::ignore_shared_strings(true); 766#endif 767 return true; 768} 769 770bool FileMapInfo::verify_string_regions() { 771 for (int i = MetaspaceShared::first_string; 772 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) { 773 if (!verify_region_checksum(i)) { 774 return false; 775 } 776 } 777 return true; 778} 779 780void FileMapInfo::fixup_string_regions() { 781#if INCLUDE_ALL_GCS 782 // If any string regions were found, call the fill routine to make them parseable. 783 // Note that string_ranges may be non-NULL even if no ranges were found. 784 if (num_ranges != 0) { 785 assert(string_ranges != NULL, "Null string_ranges array with non-zero count"); 786 G1CollectedHeap::heap()->fill_archive_regions(string_ranges, num_ranges); 787 } 788#endif 789} 790 791bool FileMapInfo::verify_region_checksum(int i) { 792 if (!VerifySharedSpaces) { 793 return true; 794 } 795 796 size_t sz = _header->_space[i]._used; 797 798 if (sz == 0) { 799 return true; // no data 800 } 801 if (MetaspaceShared::is_string_region(i) && StringTable::shared_string_ignored()) { 802 return true; // shared string data are not mapped 803 } 804 const char* buf = _header->region_addr(i); 805 int crc = ClassLoader::crc32(0, buf, (jint)sz); 806 if (crc != _header->_space[i]._crc) { 807 fail_continue("Checksum verification failed."); 808 return false; 809 } 810 return true; 811} 812 813// Unmap a memory region in the address space. 814 815void FileMapInfo::unmap_region(int i) { 816 assert(!MetaspaceShared::is_string_region(i), "sanity"); 817 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i]; 818 size_t used = si->_used; 819 size_t size = align_up(used, os::vm_allocation_granularity()); 820 821 if (used == 0) { 822 return; 823 } 824 825 char* addr = _header->region_addr(i); 826 if (!os::unmap_memory(addr, size)) { 827 fail_stop("Unable to unmap shared space."); 828 } 829} 830 831// dealloc the archived string region from java heap 832void FileMapInfo::dealloc_string_regions() { 833#if INCLUDE_ALL_GCS 834 if (num_ranges > 0) { 835 assert(string_ranges != NULL, "Null string_ranges array with non-zero count"); 836 G1CollectedHeap::heap()->dealloc_archive_regions(string_ranges, num_ranges); 837 } 838#endif 839} 840 841void FileMapInfo::assert_mark(bool check) { 842 if (!check) { 843 fail_stop("Mark mismatch while restoring from shared file."); 844 } 845} 846 847void FileMapInfo::metaspace_pointers_do(MetaspaceClosure* it) { 848 it->push(&_classpath_entry_table); 849 for (int i=0; i<_classpath_entry_table_size; i++) { 850 shared_classpath(i)->metaspace_pointers_do(it); 851 } 852} 853 854 855FileMapInfo* FileMapInfo::_current_info = NULL; 856Array<u8>* FileMapInfo::_classpath_entry_table = NULL; 857int FileMapInfo::_classpath_entry_table_size = 0; 858size_t FileMapInfo::_classpath_entry_size = 0x1234baad; 859bool FileMapInfo::_validating_classpath_entry_table = false; 860 861// Open the shared archive file, read and validate the header 862// information (version, boot classpath, etc.). If initialization 863// fails, shared spaces are disabled and the file is closed. [See 864// fail_continue.] 865// 866// Validation of the archive is done in two steps: 867// 868// [1] validate_header() - done here. This checks the header, including _paths_misc_info. 869// [2] validate_classpath_entry_table - this is done later, because the table is in the RW 870// region of the archive, which is not mapped yet. 871bool FileMapInfo::initialize() { 872 assert(UseSharedSpaces, "UseSharedSpaces expected."); 873 874 if (!open_for_read()) { 875 return false; 876 } 877 878 init_from_file(_fd); 879 if (!validate_header()) { 880 return false; 881 } 882 return true; 883} 884 885char* FileMapInfo::FileMapHeader::region_addr(int idx) { 886 if (MetaspaceShared::is_string_region(idx)) { 887 return (char*)((void*)oopDesc::decode_heap_oop_not_null( 888 (narrowOop)_space[idx]._addr._offset)); 889 } else { 890 return _space[idx]._addr._base; 891 } 892} 893 894int FileMapInfo::FileMapHeader::compute_crc() { 895 char* header = data(); 896 // start computing from the field after _crc 897 char* buf = (char*)&_crc + sizeof(int); 898 size_t sz = data_size() - (buf - header); 899 int crc = ClassLoader::crc32(0, buf, (jint)sz); 900 return crc; 901} 902 903bool FileMapInfo::FileMapHeader::validate() { 904 if (VerifySharedSpaces && compute_crc() != _crc) { 905 fail_continue("Header checksum verification failed."); 906 return false; 907 } 908 909 if (!Arguments::has_jimage()) { 910 FileMapInfo::fail_continue("The shared archive file cannot be used with an exploded module build."); 911 return false; 912 } 913 914 if (_version != current_version()) { 915 FileMapInfo::fail_continue("The shared archive file is the wrong version."); 916 return false; 917 } 918 if (_magic != (int)0xf00baba2) { 919 FileMapInfo::fail_continue("The shared archive file has a bad magic number."); 920 return false; 921 } 922 char header_version[JVM_IDENT_MAX]; 923 get_header_version(header_version); 924 if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) { 925 log_info(class, path)("expected: %s", header_version); 926 log_info(class, path)("actual: %s", _jvm_ident); 927 FileMapInfo::fail_continue("The shared archive file was created by a different" 928 " version or build of HotSpot"); 929 return false; 930 } 931 if (_obj_alignment != ObjectAlignmentInBytes) { 932 FileMapInfo::fail_continue("The shared archive file's ObjectAlignmentInBytes of %d" 933 " does not equal the current ObjectAlignmentInBytes of " INTX_FORMAT ".", 934 _obj_alignment, ObjectAlignmentInBytes); 935 return false; 936 } 937 if (_compact_strings != CompactStrings) { 938 FileMapInfo::fail_continue("The shared archive file's CompactStrings setting (%s)" 939 " does not equal the current CompactStrings setting (%s).", 940 _compact_strings ? "enabled" : "disabled", 941 CompactStrings ? "enabled" : "disabled"); 942 return false; 943 } 944 945 return true; 946} 947 948bool FileMapInfo::validate_header() { 949 bool status = _header->validate(); 950 951 if (status) { 952 if (!ClassLoader::check_shared_paths_misc_info(_paths_misc_info, _header->_paths_misc_info_size)) { 953 if (!PrintSharedArchiveAndExit) { 954 fail_continue("shared class paths mismatch (hint: enable -Xlog:class+path=info to diagnose the failure)"); 955 status = false; 956 } 957 } 958 } 959 960 if (_paths_misc_info != NULL) { 961 FREE_C_HEAP_ARRAY(char, _paths_misc_info); 962 _paths_misc_info = NULL; 963 } 964 return status; 965} 966 967// The following method is provided to see whether a given pointer 968// falls in the mapped shared space. 969// Param: 970// p, The given pointer 971// Return: 972// True if the p is within the mapped shared space, otherwise, false. 973bool FileMapInfo::is_in_shared_space(const void* p) { 974 for (int i = 0; i < MetaspaceShared::n_regions; i++) { 975 char *base; 976 if (MetaspaceShared::is_string_region(i) && _header->_space[i]._used == 0) { 977 continue; 978 } 979 base = _header->region_addr(i); 980 if (p >= base && p < base + _header->_space[i]._used) { 981 return true; 982 } 983 } 984 985 return false; 986} 987 988// Check if a given address is within one of the shared regions ( ro, rw, mc or md) 989bool FileMapInfo::is_in_shared_region(const void* p, int idx) { 990 assert(idx == MetaspaceShared::ro || 991 idx == MetaspaceShared::rw || 992 idx == MetaspaceShared::mc || 993 idx == MetaspaceShared::md, "invalid region index"); 994 char* base = _header->region_addr(idx); 995 if (p >= base && p < base + _header->_space[idx]._used) { 996 return true; 997 } 998 return false; 999} 1000 1001void FileMapInfo::print_shared_spaces() { 1002 tty->print_cr("Shared Spaces:"); 1003 for (int i = 0; i < MetaspaceShared::n_regions; i++) { 1004 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i]; 1005 char *base = _header->region_addr(i); 1006 tty->print(" %s " INTPTR_FORMAT "-" INTPTR_FORMAT, 1007 shared_region_name[i], 1008 p2i(base), p2i(base + si->_used)); 1009 } 1010} 1011 1012// Unmap mapped regions of shared space. 1013void FileMapInfo::stop_sharing_and_unmap(const char* msg) { 1014 FileMapInfo *map_info = FileMapInfo::current_info(); 1015 if (map_info) { 1016 map_info->fail_continue("%s", msg); 1017 for (int i = 0; i < MetaspaceShared::num_non_strings; i++) { 1018 char *addr = map_info->_header->region_addr(i); 1019 if (addr != NULL && !MetaspaceShared::is_string_region(i)) { 1020 map_info->unmap_region(i); 1021 map_info->_header->_space[i]._addr._base = NULL; 1022 } 1023 } 1024 // Dealloc the string regions only without unmapping. The string regions are part 1025 // of the java heap. Unmapping of the heap regions are managed by GC. 1026 map_info->dealloc_string_regions(); 1027 } else if (DumpSharedSpaces) { 1028 fail_stop("%s", msg); 1029 } 1030} 1031