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