1 /*
2 * Copyright (c) 2003, 2018, 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.inline.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 #include "logging/log.hpp"
35 #include "logging/logStream.hpp"
36 #include "logging/logMessage.hpp"
37 #include "memory/filemap.hpp"
38 #include "memory/metadataFactory.hpp"
39 #include "memory/metaspaceClosure.hpp"
40 #include "memory/metaspaceShared.hpp"
41 #include "memory/oopFactory.hpp"
42 #include "oops/compressedOops.inline.hpp"
43 #include "oops/objArrayOop.hpp"
44 #include "prims/jvmtiExport.hpp"
45 #include "runtime/arguments.hpp"
46 #include "runtime/java.hpp"
47 #include "runtime/os.hpp"
48 #include "runtime/vm_version.hpp"
49 #include "services/memTracker.hpp"
50 #include "utilities/align.hpp"
51 #include "utilities/defaultStream.hpp"
52 #if INCLUDE_ALL_GCS
53 #include "gc/g1/g1CollectedHeap.hpp"
54 #endif
55
56 # include <sys/stat.h>
57 # include <errno.h>
58
59 #ifndef O_BINARY // if defined (Win32) use binary files.
60 #define O_BINARY 0 // otherwise do nothing.
61 #endif
62
63 extern address JVM_FunctionAtStart();
64 extern address JVM_FunctionAtEnd();
65
66 // Complain and stop. All error conditions occurring during the writing of
67 // an archive file should stop the process. Unrecoverable errors during
68 // the reading of the archive file should stop the process.
69
70 static void fail(const char *msg, va_list ap) {
71 // This occurs very early during initialization: tty is not initialized.
72 jio_fprintf(defaultStream::error_stream(),
73 "An error has occurred while processing the"
74 " shared archive file.\n");
75 jio_vfprintf(defaultStream::error_stream(), msg, ap);
76 jio_fprintf(defaultStream::error_stream(), "\n");
77 // Do not change the text of the below message because some tests check for it.
78 vm_exit_during_initialization("Unable to use shared archive.", NULL);
79 }
80
81
82 void FileMapInfo::fail_stop(const char *msg, ...) {
83 va_list ap;
84 va_start(ap, msg);
85 fail(msg, ap); // Never returns.
86 va_end(ap); // for completeness.
87 }
88
89
90 // Complain and continue. Recoverable errors during the reading of the
91 // archive file may continue (with sharing disabled).
92 //
93 // If we continue, then disable shared spaces and close the file.
94
95 void FileMapInfo::fail_continue(const char *msg, ...) {
96 va_list ap;
97 va_start(ap, msg);
98 MetaspaceShared::set_archive_loading_failed();
99 if (PrintSharedArchiveAndExit && _validating_shared_path_table) {
100 // If we are doing PrintSharedArchiveAndExit and some of the classpath entries
101 // do not validate, we can still continue "limping" to validate the remaining
102 // entries. No need to quit.
103 tty->print("[");
104 tty->vprint(msg, ap);
105 tty->print_cr("]");
106 } else {
107 if (RequireSharedSpaces) {
108 fail(msg, ap);
109 } else {
110 if (log_is_enabled(Info, cds)) {
111 ResourceMark rm;
112 LogStream ls(Log(cds)::info());
113 ls.print("UseSharedSpaces: ");
114 ls.vprint_cr(msg, ap);
115 }
116 }
117 UseSharedSpaces = false;
118 assert(current_info() != NULL, "singleton must be registered");
119 current_info()->close();
120 }
121 va_end(ap);
122 }
123
124 // Fill in the fileMapInfo structure with data about this VM instance.
125
126 // This method copies the vm version info into header_version. If the version is too
127 // long then a truncated version, which has a hash code appended to it, is copied.
128 //
129 // Using a template enables this method to verify that header_version is an array of
130 // length JVM_IDENT_MAX. This ensures that the code that writes to the CDS file and
131 // the code that reads the CDS file will both use the same size buffer. Hence, will
132 // use identical truncation. This is necessary for matching of truncated versions.
133 template <int N> static void get_header_version(char (&header_version) [N]) {
134 assert(N == JVM_IDENT_MAX, "Bad header_version size");
135
136 const char *vm_version = VM_Version::internal_vm_info_string();
137 const int version_len = (int)strlen(vm_version);
138
139 if (version_len < (JVM_IDENT_MAX-1)) {
140 strcpy(header_version, vm_version);
141
142 } else {
143 // Get the hash value. Use a static seed because the hash needs to return the same
144 // value over multiple jvm invocations.
145 unsigned int hash = AltHashing::murmur3_32(8191, (const jbyte*)vm_version, version_len);
146
147 // Truncate the ident, saving room for the 8 hex character hash value.
148 strncpy(header_version, vm_version, JVM_IDENT_MAX-9);
149
150 // Append the hash code as eight hex digits.
151 sprintf(&header_version[JVM_IDENT_MAX-9], "%08x", hash);
152 header_version[JVM_IDENT_MAX-1] = 0; // Null terminate.
153 }
154 }
155
156 FileMapInfo::FileMapInfo() {
157 assert(_current_info == NULL, "must be singleton"); // not thread safe
158 _current_info = this;
159 memset((void*)this, 0, sizeof(FileMapInfo));
160 _file_offset = 0;
161 _file_open = false;
162 _header = SharedClassUtil::allocate_file_map_header();
163 _header->_version = _invalid_version;
164 }
165
166 FileMapInfo::~FileMapInfo() {
167 assert(_current_info == this, "must be singleton"); // not thread safe
168 _current_info = NULL;
169 }
170
171 void FileMapInfo::populate_header(size_t alignment) {
172 _header->populate(this, alignment);
173 }
174
175 size_t FileMapInfo::FileMapHeader::data_size() {
176 return SharedClassUtil::file_map_header_size() - sizeof(FileMapInfo::FileMapHeaderBase);
177 }
178
179 void FileMapInfo::FileMapHeader::populate(FileMapInfo* mapinfo, size_t alignment) {
180 _magic = 0xf00baba2;
181 _version = _current_version;
182 _alignment = alignment;
183 _obj_alignment = ObjectAlignmentInBytes;
184 _compact_strings = CompactStrings;
185 _narrow_oop_mode = Universe::narrow_oop_mode();
186 _narrow_oop_base = Universe::narrow_oop_base();
187 _narrow_oop_shift = Universe::narrow_oop_shift();
188 _max_heap_size = MaxHeapSize;
189 _narrow_klass_base = Universe::narrow_klass_base();
190 _narrow_klass_shift = Universe::narrow_klass_shift();
191 _shared_path_table_size = mapinfo->_shared_path_table_size;
192 _shared_path_table = mapinfo->_shared_path_table;
193 _shared_path_entry_size = mapinfo->_shared_path_entry_size;
194
195 // The following fields are for sanity checks for whether this archive
196 // will function correctly with this JVM and the bootclasspath it's
197 // invoked with.
198
199 // JVM version string ... changes on each build.
200 get_header_version(_jvm_ident);
201 }
202
203 void SharedClassPathEntry::init(const char* name, TRAPS) {
204 _timestamp = 0;
205 _filesize = 0;
206
207 struct stat st;
208 if (os::stat(name, &st) == 0) {
209 if ((st.st_mode & S_IFMT) == S_IFDIR) {
210 if (!os::dir_is_empty(name)) {
211 ClassLoader::exit_with_path_failure(
212 "Cannot have non-empty directory in archived classpaths", name);
213 }
214 _is_dir = true;
215 } else {
216 _is_dir = false;
217 _timestamp = st.st_mtime;
218 _filesize = st.st_size;
219 }
220 } else {
221 // The file/dir must exist, or it would not have been added
222 // into ClassLoader::classpath_entry().
223 //
224 // If we can't access a jar file in the boot path, then we can't
225 // make assumptions about where classes get loaded from.
226 FileMapInfo::fail_stop("Unable to open file %s.", name);
227 }
228
229 size_t len = strlen(name) + 1;
230 _name = MetadataFactory::new_array<char>(ClassLoaderData::the_null_class_loader_data(), (int)len, THREAD);
231 strcpy(_name->data(), name);
232 }
233
234 bool SharedClassPathEntry::validate(bool is_class_path) {
235 struct stat st;
236 const char* name = this->name();
237 bool ok = true;
238 log_info(class, path)("checking shared classpath entry: %s", name);
239 if (os::stat(name, &st) != 0 && is_class_path) {
240 // If the archived module path entry does not exist at runtime, it is not fatal
241 // (no need to invalid the shared archive) because the shared runtime visibility check
242 // filters out any archived module classes that do not have a matching runtime
243 // module path location.
244 FileMapInfo::fail_continue("Required classpath entry does not exist: %s", name);
245 ok = false;
246 } else if (is_dir()) {
247 if (!os::dir_is_empty(name)) {
248 FileMapInfo::fail_continue("directory is not empty: %s", name);
249 ok = false;
250 }
251 } else if (is_jar_or_bootimage()) {
252 if (_timestamp != st.st_mtime ||
253 _filesize != st.st_size) {
254 ok = false;
255 if (PrintSharedArchiveAndExit) {
256 FileMapInfo::fail_continue(_timestamp != st.st_mtime ?
257 "Timestamp mismatch" :
258 "File size mismatch");
259 } else {
260 FileMapInfo::fail_continue("A jar/jimage file is not the one used while building"
261 " the shared archive file: %s", name);
262 }
263 }
264 }
265 return ok;
266 }
267
268 void SharedClassPathEntry::metaspace_pointers_do(MetaspaceClosure* it) {
269 it->push(&_name);
270 it->push(&_manifest);
271 }
272
273 void FileMapInfo::allocate_shared_path_table() {
274 assert(DumpSharedSpaces, "Sanity");
275
276 Thread* THREAD = Thread::current();
277 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
278 ClassPathEntry* jrt = ClassLoader::get_jrt_entry();
279
280 assert(jrt != NULL,
281 "No modular java runtime image present when allocating the CDS classpath entry table");
282
283 size_t entry_size = SharedClassUtil::shared_class_path_entry_size(); // assert ( should be 8 byte aligned??)
284 int num_boot_classpath_entries = ClassLoader::num_boot_classpath_entries();
285 int num_app_classpath_entries = ClassLoader::num_app_classpath_entries();
286 int num_module_path_entries = ClassLoader::num_module_path_entries();
287 int num_entries = num_boot_classpath_entries + num_app_classpath_entries + num_module_path_entries;
288 size_t bytes = entry_size * num_entries;
289
290 _shared_path_table = MetadataFactory::new_array<u8>(loader_data, (int)(bytes + 7 / 8), THREAD);
291 _shared_path_table_size = num_entries;
292 _shared_path_entry_size = entry_size;
293
294 // 1. boot class path
295 int i = 0;
296 ClassPathEntry* cpe = jrt;
297 while (cpe != NULL) {
298 const char* type = ((cpe == jrt) ? "jrt" : (cpe->is_jar_file() ? "jar" : "dir"));
299 log_info(class, path)("add main shared path (%s) %s", type, cpe->name());
300 SharedClassPathEntry* ent = shared_path(i);
301 ent->init(cpe->name(), THREAD);
302 if (cpe != jrt) { // No need to do jimage.
303 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error.
304 SharedClassUtil::update_shared_classpath(cpe, ent, THREAD);
305 }
306 cpe = ClassLoader::get_next_boot_classpath_entry(cpe);
307 i++;
308 }
309 assert(i == num_boot_classpath_entries,
310 "number of boot class path entry mismatch");
311
312 // 2. app class path
313 ClassPathEntry *acpe = ClassLoader::app_classpath_entries();
314 while (acpe != NULL) {
315 log_info(class, path)("add app shared path %s", acpe->name());
316 SharedClassPathEntry* ent = shared_path(i);
317 ent->init(acpe->name(), THREAD);
318 EXCEPTION_MARK;
319 SharedClassUtil::update_shared_classpath(acpe, ent, THREAD);
320 acpe = acpe->next();
321 i++;
322 }
323
324 // 3. module path
325 ClassPathEntry *mpe = ClassLoader::module_path_entries();
326 while (mpe != NULL) {
327 log_info(class, path)("add module path %s",mpe->name());
328 SharedClassPathEntry* ent = shared_path(i);
329 ent->init(mpe->name(), THREAD);
330 EXCEPTION_MARK;
331 SharedClassUtil::update_shared_classpath(mpe, ent, THREAD);
332 mpe = mpe->next();
333 i++;
334 }
335 assert(i == num_entries, "number of shared path entry mismatch");
336 }
337
338 bool FileMapInfo::validate_shared_path_table() {
339 _validating_shared_path_table = true;
340
341 _shared_path_table = _header->_shared_path_table;
342 _shared_path_entry_size = _header->_shared_path_entry_size;
343 _shared_path_table_size = _header->_shared_path_table_size;
344
345 // Note: _app_module_paths_start_index may not have a valid value if the UseAppCDS flag
346 // wasn't enabled during dump time. Therefore, we need to use the smaller of
347 // _shared_path_table_size and _app_module_paths_start_index for the _app_module_paths_start_index.
348 FileMapHeaderExt* header = (FileMapHeaderExt*)FileMapInfo::current_info()->header();
349 int module_paths_start_index = (header->_app_module_paths_start_index >= _shared_path_table_size) ?
350 _shared_path_table_size : header->_app_module_paths_start_index;
351
352 int count = _shared_path_table_size;
353
354 for (int i=0; i<count; i++) {
355 if (i < module_paths_start_index) {
356 if (shared_path(i)->validate()) {
357 log_info(class, path)("ok");
358 }
359 } else if (i >= module_paths_start_index) {
360 if (shared_path(i)->validate(false /* not a class path entry */)) {
361 log_info(class, path)("ok");
362 }
363 } else if (!PrintSharedArchiveAndExit) {
364 _validating_shared_path_table = false;
365 _shared_path_table = NULL;
366 _shared_path_table_size = 0;
367 return false;
368 }
369 }
370
371 _validating_shared_path_table = false;
372 return true;
373 }
374
375 // Read the FileMapInfo information from the file.
376
377 bool FileMapInfo::init_from_file(int fd) {
378 size_t sz = _header->data_size();
379 char* addr = _header->data();
380 size_t n = os::read(fd, addr, (unsigned int)sz);
381 if (n != sz) {
382 fail_continue("Unable to read the file header.");
383 return false;
384 }
385 if (_header->_version != current_version()) {
386 fail_continue("The shared archive file has the wrong version.");
387 return false;
388 }
389 _file_offset = (long)n;
390
391 size_t info_size = _header->_paths_misc_info_size;
392 _paths_misc_info = NEW_C_HEAP_ARRAY_RETURN_NULL(char, info_size, mtClass);
393 if (_paths_misc_info == NULL) {
394 fail_continue("Unable to read the file header.");
395 return false;
396 }
397 n = os::read(fd, _paths_misc_info, (unsigned int)info_size);
398 if (n != info_size) {
399 fail_continue("Unable to read the shared path info header.");
400 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
401 _paths_misc_info = NULL;
402 return false;
403 }
404
405 size_t len = lseek(fd, 0, SEEK_END);
406 struct FileMapInfo::FileMapHeader::space_info* si =
407 &_header->_space[MetaspaceShared::last_valid_region];
408 // The last space might be empty
409 if (si->_file_offset > len || len - si->_file_offset < si->_used) {
410 fail_continue("The shared archive file has been truncated.");
411 return false;
412 }
413
414 _file_offset += (long)n;
415 return true;
416 }
417
418
419 // Read the FileMapInfo information from the file.
420 bool FileMapInfo::open_for_read() {
421 _full_path = Arguments::GetSharedArchivePath();
422 int fd = open(_full_path, O_RDONLY | O_BINARY, 0);
423 if (fd < 0) {
424 if (errno == ENOENT) {
425 // Not locating the shared archive is ok.
426 fail_continue("Specified shared archive not found.");
427 } else {
428 fail_continue("Failed to open shared archive file (%s).",
429 os::strerror(errno));
430 }
431 return false;
432 }
433
434 _fd = fd;
435 _file_open = true;
436 return true;
437 }
438
439
440 // Write the FileMapInfo information to the file.
441
442 void FileMapInfo::open_for_write() {
443 _full_path = Arguments::GetSharedArchivePath();
444 LogMessage(cds) msg;
445 if (msg.is_info()) {
446 msg.info("Dumping shared data to file: ");
447 msg.info(" %s", _full_path);
448 }
449
450 #ifdef _WINDOWS // On Windows, need WRITE permission to remove the file.
451 chmod(_full_path, _S_IREAD | _S_IWRITE);
452 #endif
453
454 // Use remove() to delete the existing file because, on Unix, this will
455 // allow processes that have it open continued access to the file.
456 remove(_full_path);
457 int fd = open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444);
458 if (fd < 0) {
459 fail_stop("Unable to create shared archive file %s: (%s).", _full_path,
460 os::strerror(errno));
461 }
462 _fd = fd;
463 _file_offset = 0;
464 _file_open = true;
465 }
466
467
468 // Write the header to the file, seek to the next allocation boundary.
469
470 void FileMapInfo::write_header() {
471 int info_size = ClassLoader::get_shared_paths_misc_info_size();
472
473 _header->_paths_misc_info_size = info_size;
474
475 align_file_position();
476 size_t sz = _header->data_size();
477 char* addr = _header->data();
478 write_bytes(addr, (int)sz); // skip the C++ vtable
479 write_bytes(ClassLoader::get_shared_paths_misc_info(), info_size);
480 align_file_position();
481 }
482
483
484 // Dump region to file.
485
486 void FileMapInfo::write_region(int region, char* base, size_t size,
487 bool read_only, bool allow_exec) {
488 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[region];
489
490 if (_file_open) {
491 guarantee(si->_file_offset == _file_offset, "file offset mismatch.");
492 log_info(cds)("Shared file region %d: " SIZE_FORMAT_HEX_W(08)
493 " bytes, addr " INTPTR_FORMAT " file offset " SIZE_FORMAT_HEX_W(08),
494 region, size, p2i(base), _file_offset);
495 } else {
496 si->_file_offset = _file_offset;
497 }
498 if (MetaspaceShared::is_heap_region(region)) {
499 assert((base - (char*)Universe::narrow_oop_base()) % HeapWordSize == 0, "Sanity");
500 if (base != NULL) {
501 si->_addr._offset = (intx)CompressedOops::encode_not_null((oop)base);
502 } else {
503 si->_addr._offset = 0;
504 }
505 } else {
506 si->_addr._base = base;
507 }
508 si->_used = size;
509 si->_read_only = read_only;
510 si->_allow_exec = allow_exec;
511 si->_crc = ClassLoader::crc32(0, base, (jint)size);
512 write_bytes_aligned(base, (int)size);
513 }
514
515 // Write out the given archive heap memory regions. GC code combines multiple
516 // consecutive archive GC regions into one MemRegion whenever possible and
517 // produces the 'heap_mem' array.
518 //
519 // If the archive heap memory size is smaller than a single dump time GC region
520 // size, there is only one MemRegion in the array.
521 //
522 // If the archive heap memory size is bigger than one dump time GC region size,
523 // the 'heap_mem' array may contain more than one consolidated MemRegions. When
524 // the first/bottom archive GC region is a partial GC region (with the empty
525 // portion at the higher address within the region), one MemRegion is used for
526 // the bottom partial archive GC region. The rest of the consecutive archive
527 // GC regions are combined into another MemRegion.
528 //
529 // Here's the mapping from (archive heap GC regions) -> (GrowableArray<MemRegion> *regions).
530 // + We have 1 or more archive heap regions: ah0, ah1, ah2 ..... ahn
531 // + We have 1 or 2 consolidated heap memory regions: r0 and r1
532 //
533 // If there's a single archive GC region (ah0), then r0 == ah0, and r1 is empty.
534 // Otherwise:
535 //
536 // "X" represented space that's occupied by heap objects.
537 // "_" represented unused spaced in the heap region.
538 //
539 //
540 // |ah0 | ah1 | ah2| ...... | ahn |
541 // |XXXXXX|__ |XXXXX|XXXX|XXXXXXXX|XXXX|
542 // |<-r0->| |<- r1 ----------------->|
543 // ^^^
544 // |
545 // +-- gap
546 size_t FileMapInfo::write_archive_heap_regions(GrowableArray<MemRegion> *heap_mem,
547 int first_region_id, int max_num_regions) {
548 assert(max_num_regions <= 2, "Only support maximum 2 memory regions");
549
550 int arr_len = heap_mem == NULL ? 0 : heap_mem->length();
551 if(arr_len > max_num_regions) {
552 fail_stop("Unable to write archive heap memory regions: "
553 "number of memory regions exceeds maximum due to fragmentation");
554 }
555
556 size_t total_size = 0;
557 for (int i = first_region_id, arr_idx = 0;
558 i < first_region_id + max_num_regions;
559 i++, arr_idx++) {
560 char* start = NULL;
561 size_t size = 0;
562 if (arr_idx < arr_len) {
563 start = (char*)heap_mem->at(arr_idx).start();
564 size = heap_mem->at(arr_idx).byte_size();
565 total_size += size;
566 }
567
568 log_info(cds)("Archive heap region %d " INTPTR_FORMAT " - " INTPTR_FORMAT " = " SIZE_FORMAT_W(8) " bytes",
569 i, p2i(start), p2i(start + size), size);
570 write_region(i, start, size, false, false);
571 }
572 return total_size;
573 }
574
575 // Dump bytes to file -- at the current file position.
576
577 void FileMapInfo::write_bytes(const void* buffer, int nbytes) {
578 if (_file_open) {
579 int n = ::write(_fd, buffer, nbytes);
580 if (n != nbytes) {
581 // It is dangerous to leave the corrupted shared archive file around,
582 // close and remove the file. See bug 6372906.
583 close();
584 remove(_full_path);
585 fail_stop("Unable to write to shared archive file.");
586 }
587 }
588 _file_offset += nbytes;
589 }
590
591
592 // Align file position to an allocation unit boundary.
593
594 void FileMapInfo::align_file_position() {
595 size_t new_file_offset = align_up(_file_offset,
596 os::vm_allocation_granularity());
597 if (new_file_offset != _file_offset) {
598 _file_offset = new_file_offset;
599 if (_file_open) {
600 // Seek one byte back from the target and write a byte to insure
601 // that the written file is the correct length.
602 _file_offset -= 1;
603 if (lseek(_fd, (long)_file_offset, SEEK_SET) < 0) {
604 fail_stop("Unable to seek.");
605 }
606 char zero = 0;
607 write_bytes(&zero, 1);
608 }
609 }
610 }
611
612
613 // Dump bytes to file -- at the current file position.
614
615 void FileMapInfo::write_bytes_aligned(const void* buffer, int nbytes) {
616 align_file_position();
617 write_bytes(buffer, nbytes);
618 align_file_position();
619 }
620
621
622 // Close the shared archive file. This does NOT unmap mapped regions.
623
624 void FileMapInfo::close() {
625 if (_file_open) {
626 if (::close(_fd) < 0) {
627 fail_stop("Unable to close the shared archive file.");
628 }
629 _file_open = false;
630 _fd = -1;
631 }
632 }
633
634
635 // JVM/TI RedefineClasses() support:
636 // Remap the shared readonly space to shared readwrite, private.
637 bool FileMapInfo::remap_shared_readonly_as_readwrite() {
638 int idx = MetaspaceShared::ro;
639 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[idx];
640 if (!si->_read_only) {
641 // the space is already readwrite so we are done
642 return true;
643 }
644 size_t used = si->_used;
645 size_t size = align_up(used, os::vm_allocation_granularity());
646 if (!open_for_read()) {
647 return false;
648 }
649 char *addr = _header->region_addr(idx);
650 char *base = os::remap_memory(_fd, _full_path, si->_file_offset,
651 addr, size, false /* !read_only */,
652 si->_allow_exec);
653 close();
654 if (base == NULL) {
655 fail_continue("Unable to remap shared readonly space (errno=%d).", errno);
656 return false;
657 }
658 if (base != addr) {
659 fail_continue("Unable to remap shared readonly space at required address.");
660 return false;
661 }
662 si->_read_only = false;
663 return true;
664 }
665
666 // Map the whole region at once, assumed to be allocated contiguously.
667 ReservedSpace FileMapInfo::reserve_shared_memory() {
668 char* requested_addr = _header->region_addr(0);
669 size_t size = FileMapInfo::core_spaces_size();
670
671 // Reserve the space first, then map otherwise map will go right over some
672 // other reserved memory (like the code cache).
673 ReservedSpace rs(size, os::vm_allocation_granularity(), false, requested_addr);
674 if (!rs.is_reserved()) {
675 fail_continue("Unable to reserve shared space at required address "
676 INTPTR_FORMAT, p2i(requested_addr));
677 return rs;
678 }
679 // the reserved virtual memory is for mapping class data sharing archive
680 MemTracker::record_virtual_memory_type((address)rs.base(), mtClassShared);
681
682 return rs;
683 }
684
685 // Memory map a region in the address space.
686 static const char* shared_region_name[] = { "MiscData", "ReadWrite", "ReadOnly", "MiscCode", "OptionalData",
687 "String1", "String2", "OpenArchive1", "OpenArchive2" };
688
689 char* FileMapInfo::map_region(int i, char** top_ret) {
690 assert(!MetaspaceShared::is_heap_region(i), "sanity");
691 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
692 size_t used = si->_used;
693 size_t alignment = os::vm_allocation_granularity();
694 size_t size = align_up(used, alignment);
695 char *requested_addr = _header->region_addr(i);
696
697 // If a tool agent is in use (debugging enabled), we must map the address space RW
698 if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space()) {
699 si->_read_only = false;
700 }
701
702 // map the contents of the CDS archive in this memory
703 char *base = os::map_memory(_fd, _full_path, si->_file_offset,
704 requested_addr, size, si->_read_only,
705 si->_allow_exec);
706 if (base == NULL || base != requested_addr) {
707 fail_continue("Unable to map %s shared space at required address.", shared_region_name[i]);
708 return NULL;
709 }
710 #ifdef _WINDOWS
711 // This call is Windows-only because the memory_type gets recorded for the other platforms
712 // in method FileMapInfo::reserve_shared_memory(), which is not called on Windows.
713 MemTracker::record_virtual_memory_type((address)base, mtClassShared);
714 #endif
715
716
717 if (!verify_region_checksum(i)) {
718 return NULL;
719 }
720
721 *top_ret = base + size;
722 return base;
723 }
724
725 static MemRegion *string_ranges = NULL;
726 static MemRegion *open_archive_heap_ranges = NULL;
727 static int num_string_ranges = 0;
728 static int num_open_archive_heap_ranges = 0;
729
730 #if INCLUDE_CDS_JAVA_HEAP
731 //
732 // Map the shared string objects and open archive heap objects to the runtime
733 // java heap.
734 //
735 // The shared strings are mapped near the runtime java heap top. The
736 // mapped strings contain no out-going references to any other java heap
737 // regions. GC does not write into the mapped shared strings.
738 //
739 // The open archive heap objects are mapped below the shared strings in
740 // the runtime java heap. The mapped open archive heap data only contain
741 // references to the shared strings and open archive objects initially.
742 // During runtime execution, out-going references to any other java heap
743 // regions may be added. GC may mark and update references in the mapped
744 // open archive objects.
745 void FileMapInfo::map_heap_regions() {
746 if (MetaspaceShared::is_heap_object_archiving_allowed()) {
747 log_info(cds)("Archived narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d",
748 narrow_oop_mode(), p2i(narrow_oop_base()), narrow_oop_shift());
749 log_info(cds)("Archived narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
750 p2i(narrow_klass_base()), narrow_klass_shift());
751
752 // Check that all the narrow oop and klass encodings match the archive
753 if (narrow_oop_mode() != Universe::narrow_oop_mode() ||
754 narrow_oop_base() != Universe::narrow_oop_base() ||
755 narrow_oop_shift() != Universe::narrow_oop_shift() ||
756 narrow_klass_base() != Universe::narrow_klass_base() ||
757 narrow_klass_shift() != Universe::narrow_klass_shift()) {
758 if (log_is_enabled(Info, cds) && _header->_space[MetaspaceShared::first_string]._used > 0) {
759 log_info(cds)("Cached heap data from the CDS archive is being ignored. "
760 "The current CompressedOops/CompressedClassPointers encoding differs from "
761 "that archived due to heap size change. The archive was dumped using max heap "
762 "size " UINTX_FORMAT "M.", max_heap_size()/M);
763 log_info(cds)("Current narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d",
764 Universe::narrow_oop_mode(), p2i(Universe::narrow_oop_base()),
765 Universe::narrow_oop_shift());
766 log_info(cds)("Current narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
767 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift());
768 }
769 } else {
770 // First, map string regions as closed archive heap regions.
771 // GC does not write into the regions.
772 if (map_heap_data(&string_ranges,
773 MetaspaceShared::first_string,
774 MetaspaceShared::max_strings,
775 &num_string_ranges)) {
776 StringTable::set_shared_string_mapped();
777
778 // Now, map open_archive heap regions, GC can write into the regions.
779 if (map_heap_data(&open_archive_heap_ranges,
780 MetaspaceShared::first_open_archive_heap_region,
781 MetaspaceShared::max_open_archive_heap_region,
782 &num_open_archive_heap_ranges,
783 true /* open */)) {
784 MetaspaceShared::set_open_archive_heap_region_mapped();
785 }
786 }
787 }
788 } else {
789 if (log_is_enabled(Info, cds) && _header->_space[MetaspaceShared::first_string]._used > 0) {
790 log_info(cds)("Cached heap data from the CDS archive is being ignored. UseG1GC, "
791 "UseCompressedOops and UseCompressedClassPointers are required.");
792 }
793 }
794
795 if (!StringTable::shared_string_mapped()) {
796 assert(string_ranges == NULL && num_string_ranges == 0, "sanity");
797 }
798
799 if (!MetaspaceShared::open_archive_heap_region_mapped()) {
800 assert(open_archive_heap_ranges == NULL && num_open_archive_heap_ranges == 0, "sanity");
801 }
802 }
803
804 bool FileMapInfo::map_heap_data(MemRegion **heap_mem, int first,
805 int max, int* num, bool is_open_archive) {
806 MemRegion * regions = new MemRegion[max];
807 struct FileMapInfo::FileMapHeader::space_info* si;
808 int region_num = 0;
809
810 for (int i = first;
811 i < first + max; i++) {
812 si = &_header->_space[i];
813 size_t used = si->_used;
814 if (used > 0) {
815 size_t size = used;
816 char* requested_addr = (char*)((void*)CompressedOops::decode_not_null(
817 (narrowOop)si->_addr._offset));
818 regions[region_num] = MemRegion((HeapWord*)requested_addr, size / HeapWordSize);
819 region_num ++;
820 }
821 }
822
823 if (region_num == 0) {
824 return false; // no archived java heap data
825 }
826
827 // Check that ranges are within the java heap
828 if (!G1CollectedHeap::heap()->check_archive_addresses(regions, region_num)) {
829 log_info(cds)("UseSharedSpaces: Unable to allocate region, "
830 "range is not within java heap.");
831 return false;
832 }
833
834 // allocate from java heap
835 if (!G1CollectedHeap::heap()->alloc_archive_regions(
836 regions, region_num, is_open_archive)) {
837 log_info(cds)("UseSharedSpaces: Unable to allocate region, "
838 "java heap range is already in use.");
839 return false;
840 }
841
842 // Map the archived heap data. No need to call MemTracker::record_virtual_memory_type()
843 // for mapped regions as they are part of the reserved java heap, which is
844 // already recorded.
845 for (int i = 0; i < region_num; i++) {
846 si = &_header->_space[first + i];
847 char* addr = (char*)regions[i].start();
848 char* base = os::map_memory(_fd, _full_path, si->_file_offset,
849 addr, regions[i].byte_size(), si->_read_only,
850 si->_allow_exec);
851 if (base == NULL || base != addr) {
852 // dealloc the regions from java heap
853 dealloc_archive_heap_regions(regions, region_num);
854 log_info(cds)("UseSharedSpaces: Unable to map at required address in java heap.");
855 return false;
856 }
857 }
858
859 if (!verify_mapped_heap_regions(first, region_num)) {
860 // dealloc the regions from java heap
861 dealloc_archive_heap_regions(regions, region_num);
862 log_info(cds)("UseSharedSpaces: mapped heap regions are corrupt");
863 return false;
864 }
865
866 // the shared heap data is mapped successfully
867 *heap_mem = regions;
868 *num = region_num;
869 return true;
870 }
871
872 bool FileMapInfo::verify_mapped_heap_regions(int first, int num) {
873 for (int i = first;
874 i <= first + num; i++) {
875 if (!verify_region_checksum(i)) {
876 return false;
877 }
878 }
879 return true;
880 }
881
882 void FileMapInfo::fixup_mapped_heap_regions() {
883 // If any string regions were found, call the fill routine to make them parseable.
884 // Note that string_ranges may be non-NULL even if no ranges were found.
885 if (num_string_ranges != 0) {
886 assert(string_ranges != NULL, "Null string_ranges array with non-zero count");
887 G1CollectedHeap::heap()->fill_archive_regions(string_ranges, num_string_ranges);
888 }
889
890 // do the same for mapped open archive heap regions
891 if (num_open_archive_heap_ranges != 0) {
892 assert(open_archive_heap_ranges != NULL, "NULL open_archive_heap_ranges array with non-zero count");
893 G1CollectedHeap::heap()->fill_archive_regions(open_archive_heap_ranges,
894 num_open_archive_heap_ranges);
895 }
896 }
897
898 // dealloc the archive regions from java heap
899 void FileMapInfo::dealloc_archive_heap_regions(MemRegion* regions, int num) {
900 if (num > 0) {
901 assert(regions != NULL, "Null archive ranges array with non-zero count");
902 G1CollectedHeap::heap()->dealloc_archive_regions(regions, num);
903 }
904 }
905 #endif // INCLUDE_CDS_JAVA_HEAP
906
907 bool FileMapInfo::verify_region_checksum(int i) {
908 if (!VerifySharedSpaces) {
909 return true;
910 }
911
912 size_t sz = _header->_space[i]._used;
913
914 if (sz == 0) {
915 return true; // no data
916 }
917 if ((MetaspaceShared::is_string_region(i) &&
918 !StringTable::shared_string_mapped()) ||
919 (MetaspaceShared::is_open_archive_heap_region(i) &&
920 !MetaspaceShared::open_archive_heap_region_mapped())) {
921 return true; // archived heap data is not mapped
922 }
923 const char* buf = _header->region_addr(i);
924 int crc = ClassLoader::crc32(0, buf, (jint)sz);
925 if (crc != _header->_space[i]._crc) {
926 fail_continue("Checksum verification failed.");
927 return false;
928 }
929 return true;
930 }
931
932 // Unmap a memory region in the address space.
933
934 void FileMapInfo::unmap_region(int i) {
935 assert(!MetaspaceShared::is_heap_region(i), "sanity");
936 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
937 size_t used = si->_used;
938 size_t size = align_up(used, os::vm_allocation_granularity());
939
940 if (used == 0) {
941 return;
942 }
943
944 char* addr = _header->region_addr(i);
945 if (!os::unmap_memory(addr, size)) {
946 fail_stop("Unable to unmap shared space.");
947 }
948 }
949
950 void FileMapInfo::assert_mark(bool check) {
951 if (!check) {
952 fail_stop("Mark mismatch while restoring from shared file.");
953 }
954 }
955
956 void FileMapInfo::metaspace_pointers_do(MetaspaceClosure* it) {
957 it->push(&_shared_path_table);
958 for (int i=0; i<_shared_path_table_size; i++) {
959 shared_path(i)->metaspace_pointers_do(it);
960 }
961 }
962
963
964 FileMapInfo* FileMapInfo::_current_info = NULL;
965 Array<u8>* FileMapInfo::_shared_path_table = NULL;
966 int FileMapInfo::_shared_path_table_size = 0;
967 size_t FileMapInfo::_shared_path_entry_size = 0x1234baad;
968 bool FileMapInfo::_validating_shared_path_table = false;
969
970 // Open the shared archive file, read and validate the header
971 // information (version, boot classpath, etc.). If initialization
972 // fails, shared spaces are disabled and the file is closed. [See
973 // fail_continue.]
974 //
975 // Validation of the archive is done in two steps:
976 //
977 // [1] validate_header() - done here. This checks the header, including _paths_misc_info.
978 // [2] validate_shared_path_table - this is done later, because the table is in the RW
979 // region of the archive, which is not mapped yet.
980 bool FileMapInfo::initialize() {
981 assert(UseSharedSpaces, "UseSharedSpaces expected.");
982
983 if (!open_for_read()) {
984 return false;
985 }
986
987 init_from_file(_fd);
988 if (!validate_header()) {
989 return false;
990 }
991 return true;
992 }
993
994 char* FileMapInfo::FileMapHeader::region_addr(int idx) {
995 if (MetaspaceShared::is_heap_region(idx)) {
996 return _space[idx]._used > 0 ?
997 (char*)((void*)CompressedOops::decode_not_null((narrowOop)_space[idx]._addr._offset)) : NULL;
998 } else {
999 return _space[idx]._addr._base;
1000 }
1001 }
1002
1003 int FileMapInfo::FileMapHeader::compute_crc() {
1004 char* header = data();
1005 // start computing from the field after _crc
1006 char* buf = (char*)&_crc + sizeof(int);
1007 size_t sz = data_size() - (buf - header);
1008 int crc = ClassLoader::crc32(0, buf, (jint)sz);
1009 return crc;
1010 }
1011
1012 bool FileMapInfo::FileMapHeader::validate() {
1013 if (VerifySharedSpaces && compute_crc() != _crc) {
1014 fail_continue("Header checksum verification failed.");
1015 return false;
1016 }
1017
1018 if (!Arguments::has_jimage()) {
1019 FileMapInfo::fail_continue("The shared archive file cannot be used with an exploded module build.");
1020 return false;
1021 }
1022
1023 if (_version != current_version()) {
1024 FileMapInfo::fail_continue("The shared archive file is the wrong version.");
1025 return false;
1026 }
1027 if (_magic != (int)0xf00baba2) {
1028 FileMapInfo::fail_continue("The shared archive file has a bad magic number.");
1029 return false;
1030 }
1031 char header_version[JVM_IDENT_MAX];
1032 get_header_version(header_version);
1033 if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) {
1034 log_info(class, path)("expected: %s", header_version);
1035 log_info(class, path)("actual: %s", _jvm_ident);
1036 FileMapInfo::fail_continue("The shared archive file was created by a different"
1037 " version or build of HotSpot");
1038 return false;
1039 }
1040 if (_obj_alignment != ObjectAlignmentInBytes) {
1041 FileMapInfo::fail_continue("The shared archive file's ObjectAlignmentInBytes of %d"
1042 " does not equal the current ObjectAlignmentInBytes of " INTX_FORMAT ".",
1043 _obj_alignment, ObjectAlignmentInBytes);
1044 return false;
1045 }
1046 if (_compact_strings != CompactStrings) {
1047 FileMapInfo::fail_continue("The shared archive file's CompactStrings setting (%s)"
1048 " does not equal the current CompactStrings setting (%s).",
1049 _compact_strings ? "enabled" : "disabled",
1050 CompactStrings ? "enabled" : "disabled");
1051 return false;
1052 }
1053
1054 return true;
1055 }
1056
1057 bool FileMapInfo::validate_header() {
1058 bool status = _header->validate();
1059
1060 if (status) {
1061 if (!ClassLoader::check_shared_paths_misc_info(_paths_misc_info, _header->_paths_misc_info_size)) {
1062 if (!PrintSharedArchiveAndExit) {
1063 fail_continue("shared class paths mismatch (hint: enable -Xlog:class+path=info to diagnose the failure)");
1064 status = false;
1065 }
1066 }
1067 }
1068
1069 if (_paths_misc_info != NULL) {
1070 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
1071 _paths_misc_info = NULL;
1072 }
1073 return status;
1074 }
1075
1076 // Check if a given address is within one of the shared regions
1077 bool FileMapInfo::is_in_shared_region(const void* p, int idx) {
1078 assert(idx == MetaspaceShared::ro ||
1079 idx == MetaspaceShared::rw ||
1080 idx == MetaspaceShared::mc ||
1081 idx == MetaspaceShared::md, "invalid region index");
1082 char* base = _header->region_addr(idx);
1083 if (p >= base && p < base + _header->_space[idx]._used) {
1084 return true;
1085 }
1086 return false;
1087 }
1088
1089 void FileMapInfo::print_shared_spaces() {
1090 tty->print_cr("Shared Spaces:");
1091 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
1092 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
1093 char *base = _header->region_addr(i);
1094 tty->print(" %s " INTPTR_FORMAT "-" INTPTR_FORMAT,
1095 shared_region_name[i],
1096 p2i(base), p2i(base + si->_used));
1097 }
1098 }
1099
1100 // Unmap mapped regions of shared space.
1101 void FileMapInfo::stop_sharing_and_unmap(const char* msg) {
1102 FileMapInfo *map_info = FileMapInfo::current_info();
1103 if (map_info) {
1104 map_info->fail_continue("%s", msg);
1105 for (int i = 0; i < MetaspaceShared::num_non_heap_spaces; i++) {
1106 char *addr = map_info->_header->region_addr(i);
1107 if (addr != NULL && !MetaspaceShared::is_heap_region(i)) {
1108 map_info->unmap_region(i);
1109 map_info->_header->_space[i]._addr._base = NULL;
1110 }
1111 }
1112 // Dealloc the archive heap regions only without unmapping. The regions are part
1113 // of the java heap. Unmapping of the heap regions are managed by GC.
1114 map_info->dealloc_archive_heap_regions(open_archive_heap_ranges,
1115 num_open_archive_heap_ranges);
1116 map_info->dealloc_archive_heap_regions(string_ranges, num_string_ranges);
1117 } else if (DumpSharedSpaces) {
1118 fail_stop("%s", msg);
1119 }
1120 }