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