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 "jvm.h"
27 #include "classfile/classLoader.hpp"
28 #include "classfile/compactHashtable.inline.hpp"
29 #include "classfile/sharedClassUtil.hpp"
30 #include "classfile/stringTable.hpp"
31 #include "classfile/symbolTable.hpp"
32 #include "classfile/systemDictionaryShared.hpp"
33 #include "classfile/altHashing.hpp"
34 #if INCLUDE_ALL_GCS
35 #include "gc/g1/g1CollectedHeap.hpp"
36 #endif
37 #include "logging/log.hpp"
38 #include "logging/logStream.hpp"
39 #include "logging/logMessage.hpp"
40 #include "memory/filemap.hpp"
41 #include "memory/metadataFactory.hpp"
42 #include "memory/metaspaceClosure.hpp"
43 #include "memory/metaspaceShared.hpp"
44 #include "memory/oopFactory.hpp"
45 #include "oops/objArrayOop.hpp"
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
62 extern address JVM_FunctionAtStart();
63 extern 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
69 static 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
81 void 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
94 void 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.
132 template <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
155 FileMapInfo::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
165 FileMapInfo::~FileMapInfo() {
166 assert(_current_info == this, "must be singleton"); // not thread safe
167 _current_info = NULL;
168 }
169
170 void FileMapInfo::populate_header(size_t alignment) {
171 _header->populate(this, alignment);
172 }
173
174 size_t FileMapInfo::FileMapHeader::data_size() {
175 return SharedClassUtil::file_map_header_size() - sizeof(FileMapInfo::FileMapHeaderBase);
176 }
177
178 void 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_base = Universe::narrow_oop_base();
186 _narrow_oop_shift = Universe::narrow_oop_shift();
187 _max_heap_size = MaxHeapSize;
188 _narrow_klass_base = Universe::narrow_klass_base();
189 _narrow_klass_shift = Universe::narrow_klass_shift();
190 _classpath_entry_table_size = mapinfo->_classpath_entry_table_size;
191 _classpath_entry_table = mapinfo->_classpath_entry_table;
192 _classpath_entry_size = mapinfo->_classpath_entry_size;
193
194 // The following fields are for sanity checks for whether this archive
195 // will function correctly with this JVM and the bootclasspath it's
196 // invoked with.
197
198 // JVM version string ... changes on each build.
199 get_header_version(_jvm_ident);
200 }
201
202 void SharedClassPathEntry::init(const char* name, TRAPS) {
203 _timestamp = 0;
204 _filesize = 0;
205
206 struct stat st;
207 if (os::stat(name, &st) == 0) {
208 if ((st.st_mode & S_IFMT) == S_IFDIR) {
209 if (!os::dir_is_empty(name)) {
210 ClassLoader::exit_with_path_failure(
211 "Cannot have non-empty directory in archived classpaths", name);
212 }
213 _is_dir = true;
214 } else {
215 _is_dir = false;
216 _timestamp = st.st_mtime;
217 _filesize = st.st_size;
218 }
219 } else {
220 // The file/dir must exist, or it would not have been added
221 // into ClassLoader::classpath_entry().
222 //
223 // If we can't access a jar file in the boot path, then we can't
224 // make assumptions about where classes get loaded from.
225 FileMapInfo::fail_stop("Unable to open file %s.", name);
226 }
227
228 size_t len = strlen(name) + 1;
229 _name = MetadataFactory::new_array<char>(ClassLoaderData::the_null_class_loader_data(), (int)len, THREAD);
230 strcpy(_name->data(), name);
231 }
232
233 bool SharedClassPathEntry::validate() {
234 struct stat st;
235 const char* name = this->name();
236 bool ok = true;
237 log_info(class, path)("checking shared classpath entry: %s", name);
238 if (os::stat(name, &st) != 0) {
239 FileMapInfo::fail_continue("Required classpath entry does not exist: %s", name);
240 ok = false;
241 } else if (is_dir()) {
242 if (!os::dir_is_empty(name)) {
243 FileMapInfo::fail_continue("directory is not empty: %s", name);
244 ok = false;
245 }
246 } else if (is_jar_or_bootimage()) {
247 if (_timestamp != st.st_mtime ||
248 _filesize != st.st_size) {
249 ok = false;
250 if (PrintSharedArchiveAndExit) {
251 FileMapInfo::fail_continue(_timestamp != st.st_mtime ?
252 "Timestamp mismatch" :
253 "File size mismatch");
254 } else {
255 FileMapInfo::fail_continue("A jar/jimage file is not the one used while building"
256 " the shared archive file: %s", name);
257 }
258 }
259 }
260 return ok;
261 }
262
263 void SharedClassPathEntry::metaspace_pointers_do(MetaspaceClosure* it) {
264 it->push(&_name);
265 it->push(&_manifest);
266 }
267
268 void FileMapInfo::allocate_classpath_entry_table() {
269 assert(DumpSharedSpaces, "Sanity");
270
271 Thread* THREAD = Thread::current();
272 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
273 ClassPathEntry* jrt = ClassLoader::get_jrt_entry();
274
275 assert(jrt != NULL,
276 "No modular java runtime image present when allocating the CDS classpath entry table");
277
278 size_t entry_size = SharedClassUtil::shared_class_path_entry_size(); // assert ( should be 8 byte aligned??)
279 int num_boot_classpath_entries = ClassLoader::num_boot_classpath_entries();
280 int num_app_classpath_entries = ClassLoader::num_app_classpath_entries();
281 int num_entries = num_boot_classpath_entries + num_app_classpath_entries;
282 size_t bytes = entry_size * num_entries;
283
284 _classpath_entry_table = MetadataFactory::new_array<u8>(loader_data, (int)(bytes + 7 / 8), THREAD);
285 _classpath_entry_table_size = num_entries;
286 _classpath_entry_size = entry_size;
287
288 // 1. boot class path
289 int i = 0;
290 ClassPathEntry* cpe = jrt;
291 while (cpe != NULL) {
292 const char* type = ((cpe == jrt) ? "jrt" : (cpe->is_jar_file() ? "jar" : "dir"));
293 log_info(class, path)("add main shared path (%s) %s", type, cpe->name());
294 SharedClassPathEntry* ent = shared_classpath(i);
295 ent->init(cpe->name(), THREAD);
296 if (cpe != jrt) { // No need to do jimage.
297 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error.
298 SharedClassUtil::update_shared_classpath(cpe, ent, THREAD);
299 }
300 cpe = ClassLoader::get_next_boot_classpath_entry(cpe);
301 i++;
302 }
303 assert(i == num_boot_classpath_entries,
304 "number of boot class path entry mismatch");
305
306 // 2. app class path
307 ClassPathEntry *acpe = ClassLoader::app_classpath_entries();
308 while (acpe != NULL) {
309 log_info(class, path)("add app shared path %s", acpe->name());
310 SharedClassPathEntry* ent = shared_classpath(i);
311 ent->init(acpe->name(), THREAD);
312 EXCEPTION_MARK;
313 SharedClassUtil::update_shared_classpath(acpe, ent, THREAD);
314 acpe = acpe->next();
315 i ++;
316 }
317 assert(i == num_entries, "number of app class path entry mismatch");
318 }
319
320 bool FileMapInfo::validate_classpath_entry_table() {
321 _validating_classpath_entry_table = true;
322
323 int count = _header->_classpath_entry_table_size;
324
325 _classpath_entry_table = _header->_classpath_entry_table;
326 _classpath_entry_size = _header->_classpath_entry_size;
327 _classpath_entry_table_size = _header->_classpath_entry_table_size;
328
329 for (int i=0; i<count; i++) {
330 if (shared_classpath(i)->validate()) {
331 log_info(class, path)("ok");
332 } else if (!PrintSharedArchiveAndExit) {
333 _validating_classpath_entry_table = false;
334 _classpath_entry_table = NULL;
335 _classpath_entry_table_size = 0;
336 return false;
337 }
338 }
339
340 _validating_classpath_entry_table = false;
341 return true;
342 }
343
344
345 // Read the FileMapInfo information from the file.
346
347 bool FileMapInfo::init_from_file(int fd) {
348 size_t sz = _header->data_size();
349 char* addr = _header->data();
350 size_t n = os::read(fd, addr, (unsigned int)sz);
351 if (n != sz) {
352 fail_continue("Unable to read the file header.");
353 return false;
354 }
355 if (_header->_version != current_version()) {
356 fail_continue("The shared archive file has the wrong version.");
357 return false;
358 }
359 _file_offset = (long)n;
360
361 size_t info_size = _header->_paths_misc_info_size;
362 _paths_misc_info = NEW_C_HEAP_ARRAY_RETURN_NULL(char, info_size, mtClass);
363 if (_paths_misc_info == NULL) {
364 fail_continue("Unable to read the file header.");
365 return false;
366 }
367 n = os::read(fd, _paths_misc_info, (unsigned int)info_size);
368 if (n != info_size) {
369 fail_continue("Unable to read the shared path info header.");
370 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
371 _paths_misc_info = NULL;
372 return false;
373 }
374
375 size_t len = lseek(fd, 0, SEEK_END);
376 struct FileMapInfo::FileMapHeader::space_info* si =
377 &_header->_space[MetaspaceShared::last_valid_region];
378 // The last space might be empty
379 if (si->_file_offset > len || len - si->_file_offset < si->_used) {
380 fail_continue("The shared archive file has been truncated.");
381 return false;
382 }
383
384 _file_offset += (long)n;
385 return true;
386 }
387
388
389 // Read the FileMapInfo information from the file.
390 bool FileMapInfo::open_for_read() {
391 _full_path = Arguments::GetSharedArchivePath();
392 int fd = open(_full_path, O_RDONLY | O_BINARY, 0);
393 if (fd < 0) {
394 if (errno == ENOENT) {
395 // Not locating the shared archive is ok.
396 fail_continue("Specified shared archive not found.");
397 } else {
398 fail_continue("Failed to open shared archive file (%s).",
399 os::strerror(errno));
400 }
401 return false;
402 }
403
404 _fd = fd;
405 _file_open = true;
406 return true;
407 }
408
409
410 // Write the FileMapInfo information to the file.
411
412 void FileMapInfo::open_for_write() {
413 _full_path = Arguments::GetSharedArchivePath();
414 if (log_is_enabled(Info, cds)) {
415 ResourceMark rm;
416 LogMessage(cds) msg;
417 stringStream info_stream;
418 info_stream.print_cr("Dumping shared data to file: ");
419 info_stream.print_cr(" %s", _full_path);
420 msg.info("%s", info_stream.as_string());
421 }
422
423 #ifdef _WINDOWS // On Windows, need WRITE permission to remove the file.
424 chmod(_full_path, _S_IREAD | _S_IWRITE);
425 #endif
426
427 // Use remove() to delete the existing file because, on Unix, this will
428 // allow processes that have it open continued access to the file.
429 remove(_full_path);
430 int fd = open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444);
431 if (fd < 0) {
432 fail_stop("Unable to create shared archive file %s: (%s).", _full_path,
433 os::strerror(errno));
434 }
435 _fd = fd;
436 _file_offset = 0;
437 _file_open = true;
438 }
439
440
441 // Write the header to the file, seek to the next allocation boundary.
442
443 void FileMapInfo::write_header() {
444 int info_size = ClassLoader::get_shared_paths_misc_info_size();
445
446 _header->_paths_misc_info_size = info_size;
447
448 align_file_position();
449 size_t sz = _header->data_size();
450 char* addr = _header->data();
451 write_bytes(addr, (int)sz); // skip the C++ vtable
452 write_bytes(ClassLoader::get_shared_paths_misc_info(), info_size);
453 align_file_position();
454 }
455
456
457 // Dump region to file.
458
459 void FileMapInfo::write_region(int region, char* base, size_t size,
460 bool read_only, bool allow_exec) {
461 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[region];
462
463 if (_file_open) {
464 guarantee(si->_file_offset == _file_offset, "file offset mismatch.");
465 log_info(cds)("Shared file region %d: " SIZE_FORMAT_HEX_W(08)
466 " bytes, addr " INTPTR_FORMAT " file offset " SIZE_FORMAT_HEX_W(08),
467 region, size, p2i(base), _file_offset);
468 } else {
469 si->_file_offset = _file_offset;
470 }
471 if (MetaspaceShared::is_heap_region(region)) {
472 assert((base - (char*)Universe::narrow_oop_base()) % HeapWordSize == 0, "Sanity");
473 if (base != NULL) {
474 si->_addr._offset = (intx)oopDesc::encode_heap_oop_not_null((oop)base);
475 } else {
476 si->_addr._offset = 0;
477 }
478 } else {
479 si->_addr._base = base;
480 }
481 si->_used = size;
482 si->_read_only = read_only;
483 si->_allow_exec = allow_exec;
484 si->_crc = ClassLoader::crc32(0, base, (jint)size);
485 write_bytes_aligned(base, (int)size);
486 }
487
488 // Write out the given archive heap memory regions. GC code combines multiple
489 // consecutive archive GC regions into one MemRegion whenever possible and
490 // produces the 'heap_mem' array.
491 //
492 // If the archive heap memory size is smaller than a single dump time GC region
493 // size, there is only one MemRegion in the array.
494 //
495 // If the archive heap memory size is bigger than one dump time GC region size,
496 // the 'heap_mem' array may contain more than one consolidated MemRegions. When
497 // the first/bottom archive GC region is a partial GC region (with the empty
498 // portion at the higher address within the region), one MemRegion is used for
499 // the bottom partial archive GC region. The rest of the consecutive archive
500 // GC regions are combined into another MemRegion.
501 //
502 // Here's the mapping from (archive heap GC regions) -> (GrowableArray<MemRegion> *regions).
503 // + We have 1 or more archive heap regions: ah0, ah1, ah2 ..... ahn
504 // + We have 1 or 2 consolidated heap memory regions: r0 and r1
505 //
506 // If there's a single archive GC region (ah0), then r0 == ah0, and r1 is empty.
507 // Otherwise:
508 //
509 // "X" represented space that's occupied by heap objects.
510 // "_" represented unused spaced in the heap region.
511 //
512 //
513 // |ah0 | ah1 | ah2| ...... | ahn |
514 // |XXXXXX|__ |XXXXX|XXXX|XXXXXXXX|XXXX|
515 // |<-r0->| |<- r1 ----------------->|
516 // ^^^
517 // |
518 // +-- gap
519 size_t FileMapInfo::write_archive_heap_regions(GrowableArray<MemRegion> *heap_mem,
520 int first_region_id, int max_num_regions) {
521 assert(max_num_regions <= 2, "Only support maximum 2 memory regions");
522
523 int arr_len = heap_mem == NULL ? 0 : heap_mem->length();
524 if(arr_len > max_num_regions) {
525 fail_stop("Unable to write archive heap memory regions: "
526 "number of memory regions exceeds maximum due to fragmentation");
527 }
528
529 size_t total_size = 0;
530 for (int i = first_region_id, arr_idx = 0;
531 i < first_region_id + max_num_regions;
532 i++, arr_idx++) {
533 char* start = NULL;
534 size_t size = 0;
535 if (arr_idx < arr_len) {
536 start = (char*)heap_mem->at(arr_idx).start();
537 size = heap_mem->at(arr_idx).byte_size();
538 total_size += size;
539 }
540
541 log_info(cds)("Archive heap region %d " INTPTR_FORMAT " - " INTPTR_FORMAT " = " SIZE_FORMAT_W(8) " bytes",
542 i, p2i(start), p2i(start + size), size);
543 write_region(i, start, size, false, false);
544 }
545 return total_size;
546 }
547
548 // Dump bytes to file -- at the current file position.
549
550 void FileMapInfo::write_bytes(const void* buffer, int nbytes) {
551 if (_file_open) {
552 int n = ::write(_fd, buffer, nbytes);
553 if (n != nbytes) {
554 // It is dangerous to leave the corrupted shared archive file around,
555 // close and remove the file. See bug 6372906.
556 close();
557 remove(_full_path);
558 fail_stop("Unable to write to shared archive file.");
559 }
560 }
561 _file_offset += nbytes;
562 }
563
564
565 // Align file position to an allocation unit boundary.
566
567 void FileMapInfo::align_file_position() {
568 size_t new_file_offset = align_up(_file_offset,
569 os::vm_allocation_granularity());
570 if (new_file_offset != _file_offset) {
571 _file_offset = new_file_offset;
572 if (_file_open) {
573 // Seek one byte back from the target and write a byte to insure
574 // that the written file is the correct length.
575 _file_offset -= 1;
576 if (lseek(_fd, (long)_file_offset, SEEK_SET) < 0) {
577 fail_stop("Unable to seek.");
578 }
579 char zero = 0;
580 write_bytes(&zero, 1);
581 }
582 }
583 }
584
585
586 // Dump bytes to file -- at the current file position.
587
588 void FileMapInfo::write_bytes_aligned(const void* buffer, int nbytes) {
589 align_file_position();
590 write_bytes(buffer, nbytes);
591 align_file_position();
592 }
593
594
595 // Close the shared archive file. This does NOT unmap mapped regions.
596
597 void FileMapInfo::close() {
598 if (_file_open) {
599 if (::close(_fd) < 0) {
600 fail_stop("Unable to close the shared archive file.");
601 }
602 _file_open = false;
603 _fd = -1;
604 }
605 }
606
607
608 // JVM/TI RedefineClasses() support:
609 // Remap the shared readonly space to shared readwrite, private.
610 bool FileMapInfo::remap_shared_readonly_as_readwrite() {
611 int idx = MetaspaceShared::ro;
612 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[idx];
613 if (!si->_read_only) {
614 // the space is already readwrite so we are done
615 return true;
616 }
617 size_t used = si->_used;
618 size_t size = align_up(used, os::vm_allocation_granularity());
619 if (!open_for_read()) {
620 return false;
621 }
622 char *addr = _header->region_addr(idx);
623 char *base = os::remap_memory(_fd, _full_path, si->_file_offset,
624 addr, size, false /* !read_only */,
625 si->_allow_exec);
626 close();
627 if (base == NULL) {
628 fail_continue("Unable to remap shared readonly space (errno=%d).", errno);
629 return false;
630 }
631 if (base != addr) {
632 fail_continue("Unable to remap shared readonly space at required address.");
633 return false;
634 }
635 si->_read_only = false;
636 return true;
637 }
638
639 // Map the whole region at once, assumed to be allocated contiguously.
640 ReservedSpace FileMapInfo::reserve_shared_memory() {
641 char* requested_addr = _header->region_addr(0);
642 size_t size = FileMapInfo::core_spaces_size();
643
644 // Reserve the space first, then map otherwise map will go right over some
645 // other reserved memory (like the code cache).
646 ReservedSpace rs(size, os::vm_allocation_granularity(), false, requested_addr);
647 if (!rs.is_reserved()) {
648 fail_continue("Unable to reserve shared space at required address "
649 INTPTR_FORMAT, p2i(requested_addr));
650 return rs;
651 }
652 // the reserved virtual memory is for mapping class data sharing archive
653 MemTracker::record_virtual_memory_type((address)rs.base(), mtClassShared);
654
655 return rs;
656 }
657
658 // Memory map a region in the address space.
659 static const char* shared_region_name[] = { "MiscData", "ReadWrite", "ReadOnly", "MiscCode", "OptionalData",
660 "String1", "String2", "OpenArchive1", "OpenArchive2" };
661
662 char* FileMapInfo::map_region(int i) {
663 assert(!MetaspaceShared::is_heap_region(i), "sanity");
664 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
665 size_t used = si->_used;
666 size_t alignment = os::vm_allocation_granularity();
667 size_t size = align_up(used, alignment);
668 char *requested_addr = _header->region_addr(i);
669
670 // If a tool agent is in use (debugging enabled), we must map the address space RW
671 if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space()) {
672 si->_read_only = false;
673 }
674
675 // map the contents of the CDS archive in this memory
676 char *base = os::map_memory(_fd, _full_path, si->_file_offset,
677 requested_addr, size, si->_read_only,
678 si->_allow_exec);
679 if (base == NULL || base != requested_addr) {
680 fail_continue("Unable to map %s shared space at required address.", shared_region_name[i]);
681 return NULL;
682 }
683 #ifdef _WINDOWS
684 // This call is Windows-only because the memory_type gets recorded for the other platforms
685 // in method FileMapInfo::reserve_shared_memory(), which is not called on Windows.
686 MemTracker::record_virtual_memory_type((address)base, mtClassShared);
687 #endif
688
689 return base;
690 }
691
692 static MemRegion *string_ranges = NULL;
693 static MemRegion *open_archive_heap_ranges = NULL;
694 static int num_string_ranges = 0;
695 static int num_open_archive_heap_ranges = 0;
696
697 #if INCLUDE_CDS_JAVA_HEAP
698 //
699 // Map the shared string objects and open archive heap objects to the runtime
700 // java heap.
701 //
702 // The shared strings are mapped near the runtime java heap top. The
703 // mapped strings contain no out-going references to any other java heap
704 // regions. GC does not write into the mapped shared strings.
705 //
706 // The open archive heap objects are mapped below the shared strings in
707 // the runtime java heap. The mapped open archive heap data only contain
708 // references to the shared strings and open archive objects initially.
709 // During runtime execution, out-going references to any other java heap
710 // regions may be added. GC may mark and update references in the mapped
711 // open archive objects.
712 void FileMapInfo::map_heap_regions() {
713 if (MetaspaceShared::is_heap_object_archiving_allowed()) {
714 log_info(cds)("Archived narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d",
715 narrow_oop_mode(), p2i(narrow_oop_base()), narrow_oop_shift());
716 log_info(cds)("Archived narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
717 p2i(narrow_klass_base()), narrow_klass_shift());
718
719 // Check that all the narrow oop and klass encodings match the archive
720 if (narrow_oop_mode() != Universe::narrow_oop_mode() ||
721 narrow_oop_base() != Universe::narrow_oop_base() ||
722 narrow_oop_shift() != Universe::narrow_oop_shift() ||
723 narrow_klass_base() != Universe::narrow_klass_base() ||
724 narrow_klass_shift() != Universe::narrow_klass_shift()) {
725 if (log_is_enabled(Info, cds) && _header->_space[MetaspaceShared::first_string]._used > 0) {
726 log_info(cds)("Cached heap data from the CDS archive is being ignored. "
727 "The current CompressedOops/CompressedClassPointers encoding differs from "
728 "that archived due to heap size change. The archive was dumped using max heap "
729 "size " UINTX_FORMAT "M.", max_heap_size()/M);
730 log_info(cds)("Current narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d",
731 Universe::narrow_oop_mode(), p2i(Universe::narrow_oop_base()),
732 Universe::narrow_oop_shift());
733 log_info(cds)("Current narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
734 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift());
735 }
736 } else {
737 // First, map string regions as closed archive heap regions.
738 // GC does not write into the regions.
739 if (map_heap_data(&string_ranges,
740 MetaspaceShared::first_string,
741 MetaspaceShared::max_strings,
742 &num_string_ranges)) {
743 StringTable::set_shared_string_mapped();
744
745 // Now, map open_archive heap regions, GC can write into the regions.
746 if (map_heap_data(&open_archive_heap_ranges,
747 MetaspaceShared::first_open_archive_heap_region,
748 MetaspaceShared::max_open_archive_heap_region,
749 &num_open_archive_heap_ranges,
750 true /* open */)) {
751 MetaspaceShared::set_open_archive_heap_region_mapped();
752 }
753 }
754 }
755 } else {
756 if (log_is_enabled(Info, cds) && _header->_space[MetaspaceShared::first_string]._used > 0) {
757 log_info(cds)("Cached heap data from the CDS archive is being ignored. UseG1GC, "
758 "UseCompressedOops and UseCompressedClassPointers are required.");
759 }
760 }
761
762 if (!StringTable::shared_string_mapped()) {
763 assert(string_ranges == NULL && num_string_ranges == 0, "sanity");
764 }
765
766 if (!MetaspaceShared::open_archive_heap_region_mapped()) {
767 assert(open_archive_heap_ranges == NULL && num_open_archive_heap_ranges == 0, "sanity");
768 }
769 }
770
771 bool FileMapInfo::map_heap_data(MemRegion **heap_mem, int first,
772 int max, int* num, bool is_open_archive) {
773 MemRegion * regions = new MemRegion[max];
774 struct FileMapInfo::FileMapHeader::space_info* si;
775 int region_num = 0;
776
777 for (int i = first;
778 i < first + max; i++) {
779 si = &_header->_space[i];
780 size_t used = si->_used;
781 if (used > 0) {
782 size_t size = used;
783 char* requested_addr = (char*)((void*)oopDesc::decode_heap_oop_not_null(
784 (narrowOop)si->_addr._offset));
785 regions[region_num] = MemRegion((HeapWord*)requested_addr, size / HeapWordSize);
786 region_num ++;
787 }
788 }
789
790 if (region_num == 0) {
791 return false; // no archived java heap data
792 }
793
794 // Check that ranges are within the java heap
795 if (!G1CollectedHeap::heap()->check_archive_addresses(regions, region_num)) {
796 log_info(cds)("UseSharedSpaces: Unable to allocate region, "
797 "range is not within java heap.");
798 return false;
799 }
800
801 // allocate from java heap
802 if (!G1CollectedHeap::heap()->alloc_archive_regions(
803 regions, region_num, is_open_archive)) {
804 log_info(cds)("UseSharedSpaces: Unable to allocate region, "
805 "java heap range is already in use.");
806 return false;
807 }
808
809 // Map the archived heap data. No need to call MemTracker::record_virtual_memory_type()
810 // for mapped regions as they are part of the reserved java heap, which is
811 // already recorded.
812 for (int i = 0; i < region_num; i++) {
813 si = &_header->_space[first + i];
814 char* addr = (char*)regions[i].start();
815 char* base = os::map_memory(_fd, _full_path, si->_file_offset,
816 addr, regions[i].byte_size(), si->_read_only,
817 si->_allow_exec);
818 if (base == NULL || base != addr) {
819 // dealloc the regions from java heap
820 dealloc_archive_heap_regions(regions, region_num);
821 log_info(cds)("UseSharedSpaces: Unable to map at required address in java heap.");
822 return false;
823 }
824 }
825
826 if (!verify_mapped_heap_regions(first, region_num)) {
827 // dealloc the regions from java heap
828 dealloc_archive_heap_regions(regions, region_num);
829 log_info(cds)("UseSharedSpaces: mapped heap regions are corrupt");
830 return false;
831 }
832
833 // the shared heap data is mapped successfully
834 *heap_mem = regions;
835 *num = region_num;
836 return true;
837 }
838
839 bool FileMapInfo::verify_mapped_heap_regions(int first, int num) {
840 for (int i = first;
841 i <= first + num; i++) {
842 if (!verify_region_checksum(i)) {
843 return false;
844 }
845 }
846 return true;
847 }
848
849 void FileMapInfo::fixup_mapped_heap_regions() {
850 // If any string regions were found, call the fill routine to make them parseable.
851 // Note that string_ranges may be non-NULL even if no ranges were found.
852 if (num_string_ranges != 0) {
853 assert(string_ranges != NULL, "Null string_ranges array with non-zero count");
854 G1CollectedHeap::heap()->fill_archive_regions(string_ranges, num_string_ranges);
855 }
856
857 // do the same for mapped open archive heap regions
858 if (num_open_archive_heap_ranges != 0) {
859 assert(open_archive_heap_ranges != NULL, "NULL open_archive_heap_ranges array with non-zero count");
860 G1CollectedHeap::heap()->fill_archive_regions(open_archive_heap_ranges,
861 num_open_archive_heap_ranges);
862 }
863 }
864
865 // dealloc the archive regions from java heap
866 void FileMapInfo::dealloc_archive_heap_regions(MemRegion* regions, int num) {
867 if (num > 0) {
868 assert(regions != NULL, "Null archive ranges array with non-zero count");
869 G1CollectedHeap::heap()->dealloc_archive_regions(regions, num);
870 }
871 }
872 #endif // INCLUDE_CDS_JAVA_HEAP
873
874 bool FileMapInfo::verify_region_checksum(int i) {
875 if (!VerifySharedSpaces) {
876 return true;
877 }
878
879 size_t sz = _header->_space[i]._used;
880
881 if (sz == 0) {
882 return true; // no data
883 }
884 if ((MetaspaceShared::is_string_region(i) &&
885 !StringTable::shared_string_mapped()) ||
886 (MetaspaceShared::is_open_archive_heap_region(i) &&
887 !MetaspaceShared::open_archive_heap_region_mapped())) {
888 return true; // archived heap data is not mapped
889 }
890 const char* buf = _header->region_addr(i);
891 int crc = ClassLoader::crc32(0, buf, (jint)sz);
892 if (crc != _header->_space[i]._crc) {
893 fail_continue("Checksum verification failed.");
894 return false;
895 }
896 return true;
897 }
898
899 // Unmap a memory region in the address space.
900
901 void FileMapInfo::unmap_region(int i) {
902 assert(!MetaspaceShared::is_heap_region(i), "sanity");
903 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
904 size_t used = si->_used;
905 size_t size = align_up(used, os::vm_allocation_granularity());
906
907 if (used == 0) {
908 return;
909 }
910
911 char* addr = _header->region_addr(i);
912 if (!os::unmap_memory(addr, size)) {
913 fail_stop("Unable to unmap shared space.");
914 }
915 }
916
917 void FileMapInfo::assert_mark(bool check) {
918 if (!check) {
919 fail_stop("Mark mismatch while restoring from shared file.");
920 }
921 }
922
923 void FileMapInfo::metaspace_pointers_do(MetaspaceClosure* it) {
924 it->push(&_classpath_entry_table);
925 for (int i=0; i<_classpath_entry_table_size; i++) {
926 shared_classpath(i)->metaspace_pointers_do(it);
927 }
928 }
929
930
931 FileMapInfo* FileMapInfo::_current_info = NULL;
932 Array<u8>* FileMapInfo::_classpath_entry_table = NULL;
933 int FileMapInfo::_classpath_entry_table_size = 0;
934 size_t FileMapInfo::_classpath_entry_size = 0x1234baad;
935 bool FileMapInfo::_validating_classpath_entry_table = false;
936
937 // Open the shared archive file, read and validate the header
938 // information (version, boot classpath, etc.). If initialization
939 // fails, shared spaces are disabled and the file is closed. [See
940 // fail_continue.]
941 //
942 // Validation of the archive is done in two steps:
943 //
944 // [1] validate_header() - done here. This checks the header, including _paths_misc_info.
945 // [2] validate_classpath_entry_table - this is done later, because the table is in the RW
946 // region of the archive, which is not mapped yet.
947 bool FileMapInfo::initialize() {
948 assert(UseSharedSpaces, "UseSharedSpaces expected.");
949
950 if (!open_for_read()) {
951 return false;
952 }
953
954 init_from_file(_fd);
955 if (!validate_header()) {
956 return false;
957 }
958 return true;
959 }
960
961 char* FileMapInfo::FileMapHeader::region_addr(int idx) {
962 if (MetaspaceShared::is_heap_region(idx)) {
963 return _space[idx]._used > 0 ?
964 (char*)((void*)oopDesc::decode_heap_oop_not_null((narrowOop)_space[idx]._addr._offset)) : NULL;
965 } else {
966 return _space[idx]._addr._base;
967 }
968 }
969
970 int FileMapInfo::FileMapHeader::compute_crc() {
971 char* header = data();
972 // start computing from the field after _crc
973 char* buf = (char*)&_crc + sizeof(int);
974 size_t sz = data_size() - (buf - header);
975 int crc = ClassLoader::crc32(0, buf, (jint)sz);
976 return crc;
977 }
978
979 bool FileMapInfo::FileMapHeader::validate() {
980 if (VerifySharedSpaces && compute_crc() != _crc) {
981 fail_continue("Header checksum verification failed.");
982 return false;
983 }
984
985 if (!Arguments::has_jimage()) {
986 FileMapInfo::fail_continue("The shared archive file cannot be used with an exploded module build.");
987 return false;
988 }
989
990 if (_version != current_version()) {
991 FileMapInfo::fail_continue("The shared archive file is the wrong version.");
992 return false;
993 }
994 if (_magic != (int)0xf00baba2) {
995 FileMapInfo::fail_continue("The shared archive file has a bad magic number.");
996 return false;
997 }
998 char header_version[JVM_IDENT_MAX];
999 get_header_version(header_version);
1000 if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) {
1001 log_info(class, path)("expected: %s", header_version);
1002 log_info(class, path)("actual: %s", _jvm_ident);
1003 FileMapInfo::fail_continue("The shared archive file was created by a different"
1004 " version or build of HotSpot");
1005 return false;
1006 }
1007 if (_obj_alignment != ObjectAlignmentInBytes) {
1008 FileMapInfo::fail_continue("The shared archive file's ObjectAlignmentInBytes of %d"
1009 " does not equal the current ObjectAlignmentInBytes of " INTX_FORMAT ".",
1010 _obj_alignment, ObjectAlignmentInBytes);
1011 return false;
1012 }
1013 if (_compact_strings != CompactStrings) {
1014 FileMapInfo::fail_continue("The shared archive file's CompactStrings setting (%s)"
1015 " does not equal the current CompactStrings setting (%s).",
1016 _compact_strings ? "enabled" : "disabled",
1017 CompactStrings ? "enabled" : "disabled");
1018 return false;
1019 }
1020
1021 return true;
1022 }
1023
1024 bool FileMapInfo::validate_header() {
1025 bool status = _header->validate();
1026
1027 if (status) {
1028 if (!ClassLoader::check_shared_paths_misc_info(_paths_misc_info, _header->_paths_misc_info_size)) {
1029 if (!PrintSharedArchiveAndExit) {
1030 fail_continue("shared class paths mismatch (hint: enable -Xlog:class+path=info to diagnose the failure)");
1031 status = false;
1032 }
1033 }
1034 }
1035
1036 if (_paths_misc_info != NULL) {
1037 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
1038 _paths_misc_info = NULL;
1039 }
1040 return status;
1041 }
1042
1043 // The following method is provided to see whether a given pointer
1044 // falls in the mapped shared metadata space.
1045 // Param:
1046 // p, The given pointer
1047 // Return:
1048 // True if the p is within the mapped shared space, otherwise, false.
1049 bool FileMapInfo::is_in_shared_space(const void* p) {
1050 for (int i = 0; i < MetaspaceShared::num_non_heap_spaces; i++) {
1051 char *base;
1052 if (_header->_space[i]._used == 0) {
1053 continue;
1054 }
1055 base = _header->region_addr(i);
1056 if (p >= base && p < base + _header->_space[i]._used) {
1057 return true;
1058 }
1059 }
1060
1061 return false;
1062 }
1063
1064 // Check if a given address is within one of the shared regions
1065 bool FileMapInfo::is_in_shared_region(const void* p, int idx) {
1066 assert(idx == MetaspaceShared::ro ||
1067 idx == MetaspaceShared::rw ||
1068 idx == MetaspaceShared::mc ||
1069 idx == MetaspaceShared::md, "invalid region index");
1070 char* base = _header->region_addr(idx);
1071 if (p >= base && p < base + _header->_space[idx]._used) {
1072 return true;
1073 }
1074 return false;
1075 }
1076
1077 void FileMapInfo::print_shared_spaces() {
1078 tty->print_cr("Shared Spaces:");
1079 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
1080 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
1081 char *base = _header->region_addr(i);
1082 tty->print(" %s " INTPTR_FORMAT "-" INTPTR_FORMAT,
1083 shared_region_name[i],
1084 p2i(base), p2i(base + si->_used));
1085 }
1086 }
1087
1088 // Unmap mapped regions of shared space.
1089 void FileMapInfo::stop_sharing_and_unmap(const char* msg) {
1090 FileMapInfo *map_info = FileMapInfo::current_info();
1091 if (map_info) {
1092 map_info->fail_continue("%s", msg);
1093 for (int i = 0; i < MetaspaceShared::num_non_heap_spaces; i++) {
1094 char *addr = map_info->_header->region_addr(i);
1095 if (addr != NULL && !MetaspaceShared::is_heap_region(i)) {
1096 map_info->unmap_region(i);
1097 map_info->_header->_space[i]._addr._base = NULL;
1098 }
1099 }
1100 // Dealloc the archive heap regions only without unmapping. The regions are part
1101 // of the java heap. Unmapping of the heap regions are managed by GC.
1102 map_info->dealloc_archive_heap_regions(open_archive_heap_ranges,
1103 num_open_archive_heap_ranges);
1104 map_info->dealloc_archive_heap_regions(string_ranges, num_string_ranges);
1105 } else if (DumpSharedSpaces) {
1106 fail_stop("%s", msg);
1107 }
1108 }