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 _is_dir = true;
211 } else {
212 _is_dir = false;
213 _timestamp = st.st_mtime;
214 _filesize = st.st_size;
215 }
216 } else {
217 // The file/dir must exist, or it would not have been added
218 // into ClassLoader::classpath_entry().
219 //
220 // If we can't access a jar file in the boot path, then we can't
221 // make assumptions about where classes get loaded from.
222 FileMapInfo::fail_stop("Unable to open file %s.", name);
223 }
224
225 size_t len = strlen(name) + 1;
226 _name = MetadataFactory::new_array<char>(ClassLoaderData::the_null_class_loader_data(), (int)len, THREAD);
227 strcpy(_name->data(), name);
228 }
229
230 bool SharedClassPathEntry::validate(bool is_class_path) {
231 assert(UseSharedSpaces, "runtime only");
232
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 && is_class_path) {
238 // If the archived module path entry does not exist at runtime, it is not fatal
239 // (no need to invalid the shared archive) because the shared runtime visibility check
240 // filters out any archived module classes that do not have a matching runtime
241 // module path location.
242 FileMapInfo::fail_continue("Required classpath entry does not exist: %s", name);
243 ok = false;
244 } else if (is_dir()) {
245 if (!os::dir_is_empty(name)) {
246 FileMapInfo::fail_continue("directory is not empty: %s", name);
247 ok = false;
248 }
249 } else if (is_jar_or_bootimage()) {
250 if (_timestamp != st.st_mtime ||
251 _filesize != st.st_size) {
252 ok = false;
253 if (PrintSharedArchiveAndExit) {
254 FileMapInfo::fail_continue(_timestamp != st.st_mtime ?
255 "Timestamp mismatch" :
256 "File size mismatch");
257 } else {
258 FileMapInfo::fail_continue("A jar/jimage file is not the one used while building"
259 " the shared archive file: %s", name);
260 }
261 }
262 }
263 return ok;
264 }
265
266 void SharedClassPathEntry::metaspace_pointers_do(MetaspaceClosure* it) {
267 it->push(&_name);
268 it->push(&_manifest);
269 }
270
271 void FileMapInfo::allocate_shared_path_table() {
272 assert(DumpSharedSpaces, "Sanity");
273
274 Thread* THREAD = Thread::current();
275 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
276 ClassPathEntry* jrt = ClassLoader::get_jrt_entry();
277
278 assert(jrt != NULL,
279 "No modular java runtime image present when allocating the CDS classpath entry table");
280
281 size_t entry_size = SharedClassUtil::shared_class_path_entry_size(); // assert ( should be 8 byte aligned??)
282 int num_boot_classpath_entries = ClassLoader::num_boot_classpath_entries();
283 int num_app_classpath_entries = ClassLoader::num_app_classpath_entries();
284 int num_module_path_entries = ClassLoader::num_module_path_entries();
285 int num_entries = num_boot_classpath_entries + num_app_classpath_entries + num_module_path_entries;
286 size_t bytes = entry_size * num_entries;
287
288 _shared_path_table = MetadataFactory::new_array<u8>(loader_data, (int)(bytes + 7 / 8), THREAD);
289 _shared_path_table_size = num_entries;
290 _shared_path_entry_size = entry_size;
291
292 // 1. boot class path
293 int i = 0;
294 ClassPathEntry* cpe = jrt;
295 while (cpe != NULL) {
296 const char* type = ((cpe == jrt) ? "jrt" : (cpe->is_jar_file() ? "jar" : "dir"));
297 log_info(class, path)("add main shared path (%s) %s", type, cpe->name());
298 SharedClassPathEntry* ent = shared_path(i);
299 ent->init(cpe->name(), THREAD);
300 if (cpe != jrt) { // No need to do jimage.
301 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error.
302 SharedClassUtil::update_shared_classpath(cpe, ent, THREAD);
303 }
304 cpe = ClassLoader::get_next_boot_classpath_entry(cpe);
305 i++;
306 }
307 assert(i == num_boot_classpath_entries,
308 "number of boot class path entry mismatch");
309
310 // 2. app class path
311 ClassPathEntry *acpe = ClassLoader::app_classpath_entries();
312 while (acpe != NULL) {
313 log_info(class, path)("add app shared path %s", acpe->name());
314 SharedClassPathEntry* ent = shared_path(i);
315 ent->init(acpe->name(), THREAD);
316 EXCEPTION_MARK;
317 SharedClassUtil::update_shared_classpath(acpe, ent, THREAD);
318 acpe = acpe->next();
319 i++;
320 }
321
322 // 3. module path
323 ClassPathEntry *mpe = ClassLoader::module_path_entries();
324 while (mpe != NULL) {
325 log_info(class, path)("add module path %s",mpe->name());
326 SharedClassPathEntry* ent = shared_path(i);
327 ent->init(mpe->name(), THREAD);
328 EXCEPTION_MARK;
329 SharedClassUtil::update_shared_classpath(mpe, ent, THREAD);
330 mpe = mpe->next();
331 i++;
332 }
333 assert(i == num_entries, "number of shared path entry mismatch");
334 }
335
336 void FileMapInfo::check_nonempty_dir_in_shared_path_table() {
337 assert(DumpSharedSpaces, "dump time only");
338 int end = _shared_path_table_size;
339 if (!ClassLoaderExt::has_platform_or_app_classes()) {
340 // only check the boot path if no app class is loaded
341 end = ClassLoaderExt::app_class_paths_start_index();
342 }
343 for (int i = 0; i < end; i++) {
344 SharedClassPathEntry *e = shared_path(i);
345 if (e->is_dir()) {
346 const char* path = e->name();
347 if (!os::dir_is_empty(path)) {
348 tty->print_cr("Error: non-empty directory '%s'", path);
349 ClassLoader::exit_with_path_failure("Cannot have non-empty directory in paths", NULL);
350 }
351 }
352 }
353 }
354
355 bool FileMapInfo::validate_shared_path_table() {
356 assert(UseSharedSpaces, "runtime only");
357
358 _validating_shared_path_table = true;
359 _shared_path_table = _header->_shared_path_table;
360 _shared_path_entry_size = _header->_shared_path_entry_size;
361 _shared_path_table_size = _header->_shared_path_table_size;
362
363 FileMapHeaderExt* header = (FileMapHeaderExt*)FileMapInfo::current_info()->header();
364 int module_paths_start_index = header->_app_module_paths_start_index;
365
366 // If the shared archive contain app or platform classes, validate all entries
367 // in the shared path table. Otherwise, only validate the boot path entries (with
368 // entry index < _app_class_paths_start_index).
369 int count = header->has_platform_or_app_classes() ?
370 _shared_path_table_size : header->_app_class_paths_start_index;
371
372 for (int i=0; i<count; i++) {
373 if (i < module_paths_start_index) {
374 if (shared_path(i)->validate()) {
375 log_info(class, path)("ok");
376 }
377 } else if (i >= module_paths_start_index) {
378 if (shared_path(i)->validate(false /* not a class path entry */)) {
379 log_info(class, path)("ok");
380 }
381 } else if (!PrintSharedArchiveAndExit) {
382 _validating_shared_path_table = false;
383 _shared_path_table = NULL;
384 _shared_path_table_size = 0;
385 return false;
386 }
387 }
388
389 _validating_shared_path_table = false;
390 return true;
391 }
392
393 // Read the FileMapInfo information from the file.
394
395 bool FileMapInfo::init_from_file(int fd) {
396 size_t sz = _header->data_size();
397 char* addr = _header->data();
398 size_t n = os::read(fd, addr, (unsigned int)sz);
399 if (n != sz) {
400 fail_continue("Unable to read the file header.");
401 return false;
402 }
403 if (_header->_version != current_version()) {
404 fail_continue("The shared archive file has the wrong version.");
405 return false;
406 }
407 _file_offset = (long)n;
408
409 size_t info_size = _header->_paths_misc_info_size;
410 _paths_misc_info = NEW_C_HEAP_ARRAY_RETURN_NULL(char, info_size, mtClass);
411 if (_paths_misc_info == NULL) {
412 fail_continue("Unable to read the file header.");
413 return false;
414 }
415 n = os::read(fd, _paths_misc_info, (unsigned int)info_size);
416 if (n != info_size) {
417 fail_continue("Unable to read the shared path info header.");
418 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
419 _paths_misc_info = NULL;
420 return false;
421 }
422
423 size_t len = lseek(fd, 0, SEEK_END);
424 struct FileMapInfo::FileMapHeader::space_info* si =
425 &_header->_space[MetaspaceShared::last_valid_region];
426 // The last space might be empty
427 if (si->_file_offset > len || len - si->_file_offset < si->_used) {
428 fail_continue("The shared archive file has been truncated.");
429 return false;
430 }
431
432 _file_offset += (long)n;
433 return true;
434 }
435
436
437 // Read the FileMapInfo information from the file.
438 bool FileMapInfo::open_for_read() {
439 _full_path = Arguments::GetSharedArchivePath();
440 int fd = open(_full_path, O_RDONLY | O_BINARY, 0);
441 if (fd < 0) {
442 if (errno == ENOENT) {
443 // Not locating the shared archive is ok.
444 fail_continue("Specified shared archive not found.");
445 } else {
446 fail_continue("Failed to open shared archive file (%s).",
447 os::strerror(errno));
448 }
449 return false;
450 }
451
452 _fd = fd;
453 _file_open = true;
454 return true;
455 }
456
457
458 // Write the FileMapInfo information to the file.
459
460 void FileMapInfo::open_for_write() {
461 _full_path = Arguments::GetSharedArchivePath();
462 LogMessage(cds) msg;
463 if (msg.is_info()) {
464 msg.info("Dumping shared data to file: ");
465 msg.info(" %s", _full_path);
466 }
467
468 #ifdef _WINDOWS // On Windows, need WRITE permission to remove the file.
469 chmod(_full_path, _S_IREAD | _S_IWRITE);
470 #endif
471
472 // Use remove() to delete the existing file because, on Unix, this will
473 // allow processes that have it open continued access to the file.
474 remove(_full_path);
475 int fd = open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444);
476 if (fd < 0) {
477 fail_stop("Unable to create shared archive file %s: (%s).", _full_path,
478 os::strerror(errno));
479 }
480 _fd = fd;
481 _file_offset = 0;
482 _file_open = true;
483 }
484
485
486 // Write the header to the file, seek to the next allocation boundary.
487
488 void FileMapInfo::write_header() {
489 int info_size = ClassLoader::get_shared_paths_misc_info_size();
490
491 _header->_paths_misc_info_size = info_size;
492
493 align_file_position();
494 size_t sz = _header->data_size();
495 char* addr = _header->data();
496 write_bytes(addr, (int)sz); // skip the C++ vtable
497 write_bytes(ClassLoader::get_shared_paths_misc_info(), info_size);
498 align_file_position();
499 }
500
501
502 // Dump region to file.
503
504 void FileMapInfo::write_region(int region, char* base, size_t size,
505 bool read_only, bool allow_exec) {
506 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[region];
507
508 if (_file_open) {
509 guarantee(si->_file_offset == _file_offset, "file offset mismatch.");
510 log_info(cds)("Shared file region %d: " SIZE_FORMAT_HEX_W(08)
511 " bytes, addr " INTPTR_FORMAT " file offset " SIZE_FORMAT_HEX_W(08),
512 region, size, p2i(base), _file_offset);
513 } else {
514 si->_file_offset = _file_offset;
515 }
516 if (MetaspaceShared::is_heap_region(region)) {
517 assert((base - (char*)Universe::narrow_oop_base()) % HeapWordSize == 0, "Sanity");
518 if (base != NULL) {
519 si->_addr._offset = (intx)CompressedOops::encode_not_null((oop)base);
520 } else {
521 si->_addr._offset = 0;
522 }
523 } else {
524 si->_addr._base = base;
525 }
526 si->_used = size;
527 si->_read_only = read_only;
528 si->_allow_exec = allow_exec;
529 si->_crc = ClassLoader::crc32(0, base, (jint)size);
530 write_bytes_aligned(base, (int)size);
531 }
532
533 // Write out the given archive heap memory regions. GC code combines multiple
534 // consecutive archive GC regions into one MemRegion whenever possible and
535 // produces the 'heap_mem' array.
536 //
537 // If the archive heap memory size is smaller than a single dump time GC region
538 // size, there is only one MemRegion in the array.
539 //
540 // If the archive heap memory size is bigger than one dump time GC region size,
541 // the 'heap_mem' array may contain more than one consolidated MemRegions. When
542 // the first/bottom archive GC region is a partial GC region (with the empty
543 // portion at the higher address within the region), one MemRegion is used for
544 // the bottom partial archive GC region. The rest of the consecutive archive
545 // GC regions are combined into another MemRegion.
546 //
547 // Here's the mapping from (archive heap GC regions) -> (GrowableArray<MemRegion> *regions).
548 // + We have 1 or more archive heap regions: ah0, ah1, ah2 ..... ahn
549 // + We have 1 or 2 consolidated heap memory regions: r0 and r1
550 //
551 // If there's a single archive GC region (ah0), then r0 == ah0, and r1 is empty.
552 // Otherwise:
553 //
554 // "X" represented space that's occupied by heap objects.
555 // "_" represented unused spaced in the heap region.
556 //
557 //
558 // |ah0 | ah1 | ah2| ...... | ahn |
559 // |XXXXXX|__ |XXXXX|XXXX|XXXXXXXX|XXXX|
560 // |<-r0->| |<- r1 ----------------->|
561 // ^^^
562 // |
563 // +-- gap
564 size_t FileMapInfo::write_archive_heap_regions(GrowableArray<MemRegion> *heap_mem,
565 int first_region_id, int max_num_regions) {
566 assert(max_num_regions <= 2, "Only support maximum 2 memory regions");
567
568 int arr_len = heap_mem == NULL ? 0 : heap_mem->length();
569 if(arr_len > max_num_regions) {
570 fail_stop("Unable to write archive heap memory regions: "
571 "number of memory regions exceeds maximum due to fragmentation");
572 }
573
574 size_t total_size = 0;
575 for (int i = first_region_id, arr_idx = 0;
576 i < first_region_id + max_num_regions;
577 i++, arr_idx++) {
578 char* start = NULL;
579 size_t size = 0;
580 if (arr_idx < arr_len) {
581 start = (char*)heap_mem->at(arr_idx).start();
582 size = heap_mem->at(arr_idx).byte_size();
583 total_size += size;
584 }
585
586 log_info(cds)("Archive heap region %d " INTPTR_FORMAT " - " INTPTR_FORMAT " = " SIZE_FORMAT_W(8) " bytes",
587 i, p2i(start), p2i(start + size), size);
588 write_region(i, start, size, false, false);
589 }
590 return total_size;
591 }
592
593 // Dump bytes to file -- at the current file position.
594
595 void FileMapInfo::write_bytes(const void* buffer, int nbytes) {
596 if (_file_open) {
597 int n = ::write(_fd, buffer, nbytes);
598 if (n != nbytes) {
599 // It is dangerous to leave the corrupted shared archive file around,
600 // close and remove the file. See bug 6372906.
601 close();
602 remove(_full_path);
603 fail_stop("Unable to write to shared archive file.");
604 }
605 }
606 _file_offset += nbytes;
607 }
608
609
610 // Align file position to an allocation unit boundary.
611
612 void FileMapInfo::align_file_position() {
613 size_t new_file_offset = align_up(_file_offset,
614 os::vm_allocation_granularity());
615 if (new_file_offset != _file_offset) {
616 _file_offset = new_file_offset;
617 if (_file_open) {
618 // Seek one byte back from the target and write a byte to insure
619 // that the written file is the correct length.
620 _file_offset -= 1;
621 if (lseek(_fd, (long)_file_offset, SEEK_SET) < 0) {
622 fail_stop("Unable to seek.");
623 }
624 char zero = 0;
625 write_bytes(&zero, 1);
626 }
627 }
628 }
629
630
631 // Dump bytes to file -- at the current file position.
632
633 void FileMapInfo::write_bytes_aligned(const void* buffer, int nbytes) {
634 align_file_position();
635 write_bytes(buffer, nbytes);
636 align_file_position();
637 }
638
639
640 // Close the shared archive file. This does NOT unmap mapped regions.
641
642 void FileMapInfo::close() {
643 if (_file_open) {
644 if (::close(_fd) < 0) {
645 fail_stop("Unable to close the shared archive file.");
646 }
647 _file_open = false;
648 _fd = -1;
649 }
650 }
651
652
653 // JVM/TI RedefineClasses() support:
654 // Remap the shared readonly space to shared readwrite, private.
655 bool FileMapInfo::remap_shared_readonly_as_readwrite() {
656 int idx = MetaspaceShared::ro;
657 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[idx];
658 if (!si->_read_only) {
659 // the space is already readwrite so we are done
660 return true;
661 }
662 size_t used = si->_used;
663 size_t size = align_up(used, os::vm_allocation_granularity());
664 if (!open_for_read()) {
665 return false;
666 }
667 char *addr = _header->region_addr(idx);
668 char *base = os::remap_memory(_fd, _full_path, si->_file_offset,
669 addr, size, false /* !read_only */,
670 si->_allow_exec);
671 close();
672 if (base == NULL) {
673 fail_continue("Unable to remap shared readonly space (errno=%d).", errno);
674 return false;
675 }
676 if (base != addr) {
677 fail_continue("Unable to remap shared readonly space at required address.");
678 return false;
679 }
680 si->_read_only = false;
681 return true;
682 }
683
684 // Map the whole region at once, assumed to be allocated contiguously.
685 ReservedSpace FileMapInfo::reserve_shared_memory() {
686 char* requested_addr = _header->region_addr(0);
687 size_t size = FileMapInfo::core_spaces_size();
688
689 // Reserve the space first, then map otherwise map will go right over some
690 // other reserved memory (like the code cache).
691 ReservedSpace rs(size, os::vm_allocation_granularity(), false, requested_addr);
692 if (!rs.is_reserved()) {
693 fail_continue("Unable to reserve shared space at required address "
694 INTPTR_FORMAT, p2i(requested_addr));
695 return rs;
696 }
697 // the reserved virtual memory is for mapping class data sharing archive
698 MemTracker::record_virtual_memory_type((address)rs.base(), mtClassShared);
699
700 return rs;
701 }
702
703 // Memory map a region in the address space.
704 static const char* shared_region_name[] = { "MiscData", "ReadWrite", "ReadOnly", "MiscCode", "OptionalData",
705 "String1", "String2", "OpenArchive1", "OpenArchive2" };
706
707 char* FileMapInfo::map_region(int i, char** top_ret) {
708 assert(!MetaspaceShared::is_heap_region(i), "sanity");
709 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
710 size_t used = si->_used;
711 size_t alignment = os::vm_allocation_granularity();
712 size_t size = align_up(used, alignment);
713 char *requested_addr = _header->region_addr(i);
714
715 // If a tool agent is in use (debugging enabled), we must map the address space RW
716 if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space()) {
717 si->_read_only = false;
718 }
719
720 // map the contents of the CDS archive in this memory
721 char *base = os::map_memory(_fd, _full_path, si->_file_offset,
722 requested_addr, size, si->_read_only,
723 si->_allow_exec);
724 if (base == NULL || base != requested_addr) {
725 fail_continue("Unable to map %s shared space at required address.", shared_region_name[i]);
726 return NULL;
727 }
728 #ifdef _WINDOWS
729 // This call is Windows-only because the memory_type gets recorded for the other platforms
730 // in method FileMapInfo::reserve_shared_memory(), which is not called on Windows.
731 MemTracker::record_virtual_memory_type((address)base, mtClassShared);
732 #endif
733
734
735 if (!verify_region_checksum(i)) {
736 return NULL;
737 }
738
739 *top_ret = base + size;
740 return base;
741 }
742
743 static MemRegion *string_ranges = NULL;
744 static MemRegion *open_archive_heap_ranges = NULL;
745 static int num_string_ranges = 0;
746 static int num_open_archive_heap_ranges = 0;
747
748 #if INCLUDE_CDS_JAVA_HEAP
749 //
750 // Map the shared string objects and open archive heap objects to the runtime
751 // java heap.
752 //
753 // The shared strings are mapped near the runtime java heap top. The
754 // mapped strings contain no out-going references to any other java heap
755 // regions. GC does not write into the mapped shared strings.
756 //
757 // The open archive heap objects are mapped below the shared strings in
758 // the runtime java heap. The mapped open archive heap data only contain
759 // references to the shared strings and open archive objects initially.
760 // During runtime execution, out-going references to any other java heap
761 // regions may be added. GC may mark and update references in the mapped
762 // open archive objects.
763 void FileMapInfo::map_heap_regions() {
764 if (MetaspaceShared::is_heap_object_archiving_allowed()) {
765 log_info(cds)("Archived narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d",
766 narrow_oop_mode(), p2i(narrow_oop_base()), narrow_oop_shift());
767 log_info(cds)("Archived narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
768 p2i(narrow_klass_base()), narrow_klass_shift());
769
770 // Check that all the narrow oop and klass encodings match the archive
771 if (narrow_oop_mode() != Universe::narrow_oop_mode() ||
772 narrow_oop_base() != Universe::narrow_oop_base() ||
773 narrow_oop_shift() != Universe::narrow_oop_shift() ||
774 narrow_klass_base() != Universe::narrow_klass_base() ||
775 narrow_klass_shift() != Universe::narrow_klass_shift()) {
776 if (log_is_enabled(Info, cds) && _header->_space[MetaspaceShared::first_string]._used > 0) {
777 log_info(cds)("Cached heap data from the CDS archive is being ignored. "
778 "The current CompressedOops/CompressedClassPointers encoding differs from "
779 "that archived due to heap size change. The archive was dumped using max heap "
780 "size " UINTX_FORMAT "M.", max_heap_size()/M);
781 log_info(cds)("Current narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d",
782 Universe::narrow_oop_mode(), p2i(Universe::narrow_oop_base()),
783 Universe::narrow_oop_shift());
784 log_info(cds)("Current narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
785 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift());
786 }
787 } else {
788 // First, map string regions as closed archive heap regions.
789 // GC does not write into the regions.
790 if (map_heap_data(&string_ranges,
791 MetaspaceShared::first_string,
792 MetaspaceShared::max_strings,
793 &num_string_ranges)) {
794 StringTable::set_shared_string_mapped();
795
796 // Now, map open_archive heap regions, GC can write into the regions.
797 if (map_heap_data(&open_archive_heap_ranges,
798 MetaspaceShared::first_open_archive_heap_region,
799 MetaspaceShared::max_open_archive_heap_region,
800 &num_open_archive_heap_ranges,
801 true /* open */)) {
802 MetaspaceShared::set_open_archive_heap_region_mapped();
803 }
804 }
805 }
806 } else {
807 if (log_is_enabled(Info, cds) && _header->_space[MetaspaceShared::first_string]._used > 0) {
808 log_info(cds)("Cached heap data from the CDS archive is being ignored. UseG1GC, "
809 "UseCompressedOops and UseCompressedClassPointers are required.");
810 }
811 }
812
813 if (!StringTable::shared_string_mapped()) {
814 assert(string_ranges == NULL && num_string_ranges == 0, "sanity");
815 }
816
817 if (!MetaspaceShared::open_archive_heap_region_mapped()) {
818 assert(open_archive_heap_ranges == NULL && num_open_archive_heap_ranges == 0, "sanity");
819 }
820 }
821
822 bool FileMapInfo::map_heap_data(MemRegion **heap_mem, int first,
823 int max, int* num, bool is_open_archive) {
824 MemRegion * regions = new MemRegion[max];
825 struct FileMapInfo::FileMapHeader::space_info* si;
826 int region_num = 0;
827
828 for (int i = first;
829 i < first + max; i++) {
830 si = &_header->_space[i];
831 size_t used = si->_used;
832 if (used > 0) {
833 size_t size = used;
834 char* requested_addr = (char*)((void*)CompressedOops::decode_not_null(
835 (narrowOop)si->_addr._offset));
836 regions[region_num] = MemRegion((HeapWord*)requested_addr, size / HeapWordSize);
837 region_num ++;
838 }
839 }
840
841 if (region_num == 0) {
842 return false; // no archived java heap data
843 }
844
845 // Check that ranges are within the java heap
846 if (!G1CollectedHeap::heap()->check_archive_addresses(regions, region_num)) {
847 log_info(cds)("UseSharedSpaces: Unable to allocate region, "
848 "range is not within java heap.");
849 return false;
850 }
851
852 // allocate from java heap
853 if (!G1CollectedHeap::heap()->alloc_archive_regions(
854 regions, region_num, is_open_archive)) {
855 log_info(cds)("UseSharedSpaces: Unable to allocate region, "
856 "java heap range is already in use.");
857 return false;
858 }
859
860 // Map the archived heap data. No need to call MemTracker::record_virtual_memory_type()
861 // for mapped regions as they are part of the reserved java heap, which is
862 // already recorded.
863 for (int i = 0; i < region_num; i++) {
864 si = &_header->_space[first + i];
865 char* addr = (char*)regions[i].start();
866 char* base = os::map_memory(_fd, _full_path, si->_file_offset,
867 addr, regions[i].byte_size(), si->_read_only,
868 si->_allow_exec);
869 if (base == NULL || base != addr) {
870 // dealloc the regions from java heap
871 dealloc_archive_heap_regions(regions, region_num);
872 log_info(cds)("UseSharedSpaces: Unable to map at required address in java heap.");
873 return false;
874 }
875 }
876
877 if (!verify_mapped_heap_regions(first, region_num)) {
878 // dealloc the regions from java heap
879 dealloc_archive_heap_regions(regions, region_num);
880 log_info(cds)("UseSharedSpaces: mapped heap regions are corrupt");
881 return false;
882 }
883
884 // the shared heap data is mapped successfully
885 *heap_mem = regions;
886 *num = region_num;
887 return true;
888 }
889
890 bool FileMapInfo::verify_mapped_heap_regions(int first, int num) {
891 for (int i = first;
892 i <= first + num; i++) {
893 if (!verify_region_checksum(i)) {
894 return false;
895 }
896 }
897 return true;
898 }
899
900 void FileMapInfo::fixup_mapped_heap_regions() {
901 // If any string regions were found, call the fill routine to make them parseable.
902 // Note that string_ranges may be non-NULL even if no ranges were found.
903 if (num_string_ranges != 0) {
904 assert(string_ranges != NULL, "Null string_ranges array with non-zero count");
905 G1CollectedHeap::heap()->fill_archive_regions(string_ranges, num_string_ranges);
906 }
907
908 // do the same for mapped open archive heap regions
909 if (num_open_archive_heap_ranges != 0) {
910 assert(open_archive_heap_ranges != NULL, "NULL open_archive_heap_ranges array with non-zero count");
911 G1CollectedHeap::heap()->fill_archive_regions(open_archive_heap_ranges,
912 num_open_archive_heap_ranges);
913 }
914 }
915
916 // dealloc the archive regions from java heap
917 void FileMapInfo::dealloc_archive_heap_regions(MemRegion* regions, int num) {
918 if (num > 0) {
919 assert(regions != NULL, "Null archive ranges array with non-zero count");
920 G1CollectedHeap::heap()->dealloc_archive_regions(regions, num);
921 }
922 }
923 #endif // INCLUDE_CDS_JAVA_HEAP
924
925 bool FileMapInfo::verify_region_checksum(int i) {
926 if (!VerifySharedSpaces) {
927 return true;
928 }
929
930 size_t sz = _header->_space[i]._used;
931
932 if (sz == 0) {
933 return true; // no data
934 }
935 if ((MetaspaceShared::is_string_region(i) &&
936 !StringTable::shared_string_mapped()) ||
937 (MetaspaceShared::is_open_archive_heap_region(i) &&
938 !MetaspaceShared::open_archive_heap_region_mapped())) {
939 return true; // archived heap data is not mapped
940 }
941 const char* buf = _header->region_addr(i);
942 int crc = ClassLoader::crc32(0, buf, (jint)sz);
943 if (crc != _header->_space[i]._crc) {
944 fail_continue("Checksum verification failed.");
945 return false;
946 }
947 return true;
948 }
949
950 // Unmap a memory region in the address space.
951
952 void FileMapInfo::unmap_region(int i) {
953 assert(!MetaspaceShared::is_heap_region(i), "sanity");
954 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
955 size_t used = si->_used;
956 size_t size = align_up(used, os::vm_allocation_granularity());
957
958 if (used == 0) {
959 return;
960 }
961
962 char* addr = _header->region_addr(i);
963 if (!os::unmap_memory(addr, size)) {
964 fail_stop("Unable to unmap shared space.");
965 }
966 }
967
968 void FileMapInfo::assert_mark(bool check) {
969 if (!check) {
970 fail_stop("Mark mismatch while restoring from shared file.");
971 }
972 }
973
974 void FileMapInfo::metaspace_pointers_do(MetaspaceClosure* it) {
975 it->push(&_shared_path_table);
976 for (int i=0; i<_shared_path_table_size; i++) {
977 shared_path(i)->metaspace_pointers_do(it);
978 }
979 }
980
981
982 FileMapInfo* FileMapInfo::_current_info = NULL;
983 Array<u8>* FileMapInfo::_shared_path_table = NULL;
984 int FileMapInfo::_shared_path_table_size = 0;
985 size_t FileMapInfo::_shared_path_entry_size = 0x1234baad;
986 bool FileMapInfo::_validating_shared_path_table = false;
987
988 // Open the shared archive file, read and validate the header
989 // information (version, boot classpath, etc.). If initialization
990 // fails, shared spaces are disabled and the file is closed. [See
991 // fail_continue.]
992 //
993 // Validation of the archive is done in two steps:
994 //
995 // [1] validate_header() - done here. This checks the header, including _paths_misc_info.
996 // [2] validate_shared_path_table - this is done later, because the table is in the RW
997 // region of the archive, which is not mapped yet.
998 bool FileMapInfo::initialize() {
999 assert(UseSharedSpaces, "UseSharedSpaces expected.");
1000
1001 if (!open_for_read()) {
1002 return false;
1003 }
1004
1005 init_from_file(_fd);
1006 if (!validate_header()) {
1007 return false;
1008 }
1009 return true;
1010 }
1011
1012 char* FileMapInfo::FileMapHeader::region_addr(int idx) {
1013 if (MetaspaceShared::is_heap_region(idx)) {
1014 return _space[idx]._used > 0 ?
1015 (char*)((void*)CompressedOops::decode_not_null((narrowOop)_space[idx]._addr._offset)) : NULL;
1016 } else {
1017 return _space[idx]._addr._base;
1018 }
1019 }
1020
1021 int FileMapInfo::FileMapHeader::compute_crc() {
1022 char* header = data();
1023 // start computing from the field after _crc
1024 char* buf = (char*)&_crc + sizeof(int);
1025 size_t sz = data_size() - (buf - header);
1026 int crc = ClassLoader::crc32(0, buf, (jint)sz);
1027 return crc;
1028 }
1029
1030 // This function should only be called during run time with UseSharedSpaces enabled.
1031 bool FileMapInfo::FileMapHeader::validate() {
1032 if (VerifySharedSpaces && compute_crc() != _crc) {
1033 fail_continue("Header checksum verification failed.");
1034 return false;
1035 }
1036
1037 if (!Arguments::has_jimage()) {
1038 FileMapInfo::fail_continue("The shared archive file cannot be used with an exploded module build.");
1039 return false;
1040 }
1041
1042 if (_version != current_version()) {
1043 FileMapInfo::fail_continue("The shared archive file is the wrong version.");
1044 return false;
1045 }
1046 if (_magic != (int)0xf00baba2) {
1047 FileMapInfo::fail_continue("The shared archive file has a bad magic number.");
1048 return false;
1049 }
1050 char header_version[JVM_IDENT_MAX];
1051 get_header_version(header_version);
1052 if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) {
1053 log_info(class, path)("expected: %s", header_version);
1054 log_info(class, path)("actual: %s", _jvm_ident);
1055 FileMapInfo::fail_continue("The shared archive file was created by a different"
1056 " version or build of HotSpot");
1057 return false;
1058 }
1059 if (_obj_alignment != ObjectAlignmentInBytes) {
1060 FileMapInfo::fail_continue("The shared archive file's ObjectAlignmentInBytes of %d"
1061 " does not equal the current ObjectAlignmentInBytes of " INTX_FORMAT ".",
1062 _obj_alignment, ObjectAlignmentInBytes);
1063 return false;
1064 }
1065 if (_compact_strings != CompactStrings) {
1066 FileMapInfo::fail_continue("The shared archive file's CompactStrings setting (%s)"
1067 " does not equal the current CompactStrings setting (%s).",
1068 _compact_strings ? "enabled" : "disabled",
1069 CompactStrings ? "enabled" : "disabled");
1070 return false;
1071 }
1072
1073 return true;
1074 }
1075
1076 bool FileMapInfo::validate_header() {
1077 bool status = _header->validate();
1078
1079 if (status) {
1080 if (!ClassLoader::check_shared_paths_misc_info(_paths_misc_info, _header->_paths_misc_info_size)) {
1081 if (!PrintSharedArchiveAndExit) {
1082 fail_continue("shared class paths mismatch (hint: enable -Xlog:class+path=info to diagnose the failure)");
1083 status = false;
1084 }
1085 }
1086 }
1087
1088 if (_paths_misc_info != NULL) {
1089 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
1090 _paths_misc_info = NULL;
1091 }
1092 return status;
1093 }
1094
1095 // Check if a given address is within one of the shared regions
1096 bool FileMapInfo::is_in_shared_region(const void* p, int idx) {
1097 assert(idx == MetaspaceShared::ro ||
1098 idx == MetaspaceShared::rw ||
1099 idx == MetaspaceShared::mc ||
1100 idx == MetaspaceShared::md, "invalid region index");
1101 char* base = _header->region_addr(idx);
1102 if (p >= base && p < base + _header->_space[idx]._used) {
1103 return true;
1104 }
1105 return false;
1106 }
1107
1108 void FileMapInfo::print_shared_spaces() {
1109 tty->print_cr("Shared Spaces:");
1110 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
1111 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
1112 char *base = _header->region_addr(i);
1113 tty->print(" %s " INTPTR_FORMAT "-" INTPTR_FORMAT,
1114 shared_region_name[i],
1115 p2i(base), p2i(base + si->_used));
1116 }
1117 }
1118
1119 // Unmap mapped regions of shared space.
1120 void FileMapInfo::stop_sharing_and_unmap(const char* msg) {
1121 FileMapInfo *map_info = FileMapInfo::current_info();
1122 if (map_info) {
1123 map_info->fail_continue("%s", msg);
1124 for (int i = 0; i < MetaspaceShared::num_non_heap_spaces; i++) {
1125 char *addr = map_info->_header->region_addr(i);
1126 if (addr != NULL && !MetaspaceShared::is_heap_region(i)) {
1127 map_info->unmap_region(i);
1128 map_info->_header->_space[i]._addr._base = NULL;
1129 }
1130 }
1131 // Dealloc the archive heap regions only without unmapping. The regions are part
1132 // of the java heap. Unmapping of the heap regions are managed by GC.
1133 map_info->dealloc_archive_heap_regions(open_archive_heap_ranges,
1134 num_open_archive_heap_ranges);
1135 map_info->dealloc_archive_heap_regions(string_ranges, num_string_ranges);
1136 } else if (DumpSharedSpaces) {
1137 fail_stop("%s", msg);
1138 }
1139 }