1 /*
2 * Copyright (c) 2003, 2014, 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 "classfile/classLoader.hpp"
27 #include "classfile/sharedClassUtil.hpp"
28 #include "classfile/symbolTable.hpp"
29 #include "classfile/systemDictionaryShared.hpp"
30 #include "classfile/altHashing.hpp"
31 #include "memory/filemap.hpp"
32 #include "memory/metadataFactory.hpp"
33 #include "memory/oopFactory.hpp"
34 #include "oops/objArrayOop.hpp"
35 #include "runtime/arguments.hpp"
36 #include "runtime/java.hpp"
37 #include "runtime/os.hpp"
38 #include "runtime/vm_version.hpp"
39 #include "services/memTracker.hpp"
40 #include "utilities/defaultStream.hpp"
41
42 # include <sys/stat.h>
43 # include <errno.h>
44
45 #ifndef O_BINARY // if defined (Win32) use binary files.
46 #define O_BINARY 0 // otherwise do nothing.
47 #endif
48
49 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
50 extern address JVM_FunctionAtStart();
51 extern address JVM_FunctionAtEnd();
52
53 // Complain and stop. All error conditions occurring during the writing of
54 // an archive file should stop the process. Unrecoverable errors during
55 // the reading of the archive file should stop the process.
56
57 static void fail(const char *msg, va_list ap) {
58 // This occurs very early during initialization: tty is not initialized.
59 jio_fprintf(defaultStream::error_stream(),
60 "An error has occurred while processing the"
61 " shared archive file.\n");
62 jio_vfprintf(defaultStream::error_stream(), msg, ap);
63 jio_fprintf(defaultStream::error_stream(), "\n");
64 // Do not change the text of the below message because some tests check for it.
65 vm_exit_during_initialization("Unable to use shared archive.", NULL);
66 }
67
68
69 void FileMapInfo::fail_stop(const char *msg, ...) {
70 va_list ap;
71 va_start(ap, msg);
72 fail(msg, ap); // Never returns.
73 va_end(ap); // for completeness.
74 }
75
76
77 // Complain and continue. Recoverable errors during the reading of the
78 // archive file may continue (with sharing disabled).
79 //
80 // If we continue, then disable shared spaces and close the file.
81
82 void FileMapInfo::fail_continue(const char *msg, ...) {
83 va_list ap;
84 va_start(ap, msg);
85 MetaspaceShared::set_archive_loading_failed();
86 if (PrintSharedArchiveAndExit && _validating_classpath_entry_table) {
87 // If we are doing PrintSharedArchiveAndExit and some of the classpath entries
88 // do not validate, we can still continue "limping" to validate the remaining
89 // entries. No need to quit.
90 tty->print("[");
91 tty->vprint(msg, ap);
92 tty->print_cr("]");
93 } else {
94 if (RequireSharedSpaces) {
95 fail(msg, ap);
96 } else {
97 if (PrintSharedSpaces) {
98 tty->print_cr("UseSharedSpaces: %s", msg);
99 }
100 }
101 UseSharedSpaces = false;
102 assert(current_info() != NULL, "singleton must be registered");
103 current_info()->close();
104 }
105 va_end(ap);
106 }
107
108 // Fill in the fileMapInfo structure with data about this VM instance.
109
110 // This method copies the vm version info into header_version. If the version is too
111 // long then a truncated version, which has a hash code appended to it, is copied.
112 //
113 // Using a template enables this method to verify that header_version is an array of
114 // length JVM_IDENT_MAX. This ensures that the code that writes to the CDS file and
115 // the code that reads the CDS file will both use the same size buffer. Hence, will
116 // use identical truncation. This is necessary for matching of truncated versions.
117 template <int N> static void get_header_version(char (&header_version) [N]) {
118 assert(N == JVM_IDENT_MAX, "Bad header_version size");
119
120 const char *vm_version = VM_Version::internal_vm_info_string();
121 const int version_len = (int)strlen(vm_version);
122
123 if (version_len < (JVM_IDENT_MAX-1)) {
124 strcpy(header_version, vm_version);
125
126 } else {
127 // Get the hash value. Use a static seed because the hash needs to return the same
128 // value over multiple jvm invocations.
129 unsigned int hash = AltHashing::murmur3_32(8191, (const jbyte*)vm_version, version_len);
130
131 // Truncate the ident, saving room for the 8 hex character hash value.
132 strncpy(header_version, vm_version, JVM_IDENT_MAX-9);
133
134 // Append the hash code as eight hex digits.
135 sprintf(&header_version[JVM_IDENT_MAX-9], "%08x", hash);
136 header_version[JVM_IDENT_MAX-1] = 0; // Null terminate.
137 }
138 }
139
140 FileMapInfo::FileMapInfo() {
141 assert(_current_info == NULL, "must be singleton"); // not thread safe
142 _current_info = this;
143 memset(this, 0, sizeof(FileMapInfo));
144 _file_offset = 0;
145 _file_open = false;
146 _header = SharedClassUtil::allocate_file_map_header();
147 _header->_version = _invalid_version;
148 }
149
150 FileMapInfo::~FileMapInfo() {
151 assert(_current_info == this, "must be singleton"); // not thread safe
152 _current_info = NULL;
153 }
154
155 void FileMapInfo::populate_header(size_t alignment) {
156 _header->populate(this, alignment);
157 }
158
159 size_t FileMapInfo::FileMapHeader::data_size() {
160 return SharedClassUtil::file_map_header_size() - sizeof(FileMapInfo::FileMapHeaderBase);
161 }
162
163 void FileMapInfo::FileMapHeader::populate(FileMapInfo* mapinfo, size_t alignment) {
164 _magic = 0xf00baba2;
165 _version = _current_version;
166 _alignment = alignment;
167 _obj_alignment = ObjectAlignmentInBytes;
168 _classpath_entry_table_size = mapinfo->_classpath_entry_table_size;
169 _classpath_entry_table = mapinfo->_classpath_entry_table;
170 _classpath_entry_size = mapinfo->_classpath_entry_size;
171
172 // The following fields are for sanity checks for whether this archive
173 // will function correctly with this JVM and the bootclasspath it's
174 // invoked with.
175
176 // JVM version string ... changes on each build.
177 get_header_version(_jvm_ident);
178 }
179
180 void FileMapInfo::allocate_classpath_entry_table() {
181 int bytes = 0;
182 int count = 0;
183 char* strptr = NULL;
184 char* strptr_max = NULL;
185 Thread* THREAD = Thread::current();
186
187 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
188 size_t entry_size = SharedClassUtil::shared_class_path_entry_size();
189
190 for (int pass=0; pass<2; pass++) {
191 ClassPathEntry *cpe = ClassLoader::classpath_entry(0);
192
193 for (int cur_entry = 0 ; cpe != NULL; cpe = cpe->next(), cur_entry++) {
194 const char *name = cpe->name();
195 int name_bytes = (int)(strlen(name) + 1);
196
197 if (pass == 0) {
198 count ++;
199 bytes += (int)entry_size;
200 bytes += name_bytes;
201 if (TraceClassPaths || (TraceClassLoading && Verbose)) {
202 tty->print_cr("[Add main shared path (%s) %s]", (cpe->is_jar_file() ? "jar" : "dir"), name);
203 }
204 } else {
205 SharedClassPathEntry* ent = shared_classpath(cur_entry);
206 if (cpe->is_jar_file()) {
207 struct stat st;
208 if (os::stat(name, &st) != 0) {
209 // The file/dir must exist, or it would not have been added
210 // into ClassLoader::classpath_entry().
211 //
212 // If we can't access a jar file in the boot path, then we can't
213 // make assumptions about where classes get loaded from.
214 FileMapInfo::fail_stop("Unable to open jar file %s.", name);
215 }
216
217 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error.
218 SharedClassUtil::update_shared_classpath(cpe, ent, st.st_mtime, st.st_size, THREAD);
219 } else {
220 struct stat st;
221 if ((os::stat(name, &st) == 0) && ((st.st_mode & S_IFDIR) == S_IFDIR)) {
222 if (!os::dir_is_empty(name)) {
223 ClassLoader::exit_with_path_failure("Cannot have non-empty directory in archived classpaths", name);
224 }
225 ent->_filesize = -1;
226 } else {
227 ent->_filesize = -2;
228 }
229 }
230 ent->_name = strptr;
231 if (strptr + name_bytes <= strptr_max) {
232 strncpy(strptr, name, (size_t)name_bytes); // name_bytes includes trailing 0.
233 strptr += name_bytes;
234 } else {
235 assert(0, "miscalculated buffer size");
236 }
237 }
238 }
239
240 if (pass == 0) {
241 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error.
242 Array<u8>* arr = MetadataFactory::new_array<u8>(loader_data, (bytes + 7)/8, THREAD);
243 strptr = (char*)(arr->data());
244 strptr_max = strptr + bytes;
245 SharedClassPathEntry* table = (SharedClassPathEntry*)strptr;
246 strptr += entry_size * count;
247
248 _classpath_entry_table_size = count;
249 _classpath_entry_table = table;
250 _classpath_entry_size = entry_size;
251 }
252 }
253 }
254
255 bool FileMapInfo::validate_classpath_entry_table() {
256 _validating_classpath_entry_table = true;
257
258 int count = _header->_classpath_entry_table_size;
259
260 _classpath_entry_table = _header->_classpath_entry_table;
261 _classpath_entry_size = _header->_classpath_entry_size;
262
263 for (int i=0; i<count; i++) {
264 SharedClassPathEntry* ent = shared_classpath(i);
265 struct stat st;
266 const char* name = ent->_name;
267 bool ok = true;
268 if (TraceClassPaths || (TraceClassLoading && Verbose)) {
269 tty->print_cr("[Checking shared classpath entry: %s]", name);
270 }
271 if (os::stat(name, &st) != 0) {
272 fail_continue("Required classpath entry does not exist: %s", name);
273 ok = false;
274 } else if (ent->is_dir()) {
275 if (!os::dir_is_empty(name)) {
276 fail_continue("directory is not empty: %s", name);
277 ok = false;
278 }
279 } else if (ent->is_jar()) {
280 if (ent->_timestamp != st.st_mtime ||
281 ent->_filesize != st.st_size) {
282 ok = false;
283 if (PrintSharedArchiveAndExit) {
284 fail_continue(ent->_timestamp != st.st_mtime ?
285 "Timestamp mismatch" :
286 "File size mismatch");
287 } else {
288 fail_continue("A jar file is not the one used while building"
289 " the shared archive file: %s", name);
290 }
291 }
292 }
293 if (ok) {
294 if (TraceClassPaths || (TraceClassLoading && Verbose)) {
295 tty->print_cr("[ok]");
296 }
297 } else if (!PrintSharedArchiveAndExit) {
298 _validating_classpath_entry_table = false;
299 return false;
300 }
301 }
302
303 _classpath_entry_table_size = _header->_classpath_entry_table_size;
304 _validating_classpath_entry_table = false;
305 return true;
306 }
307
308
309 // Read the FileMapInfo information from the file.
310
311 bool FileMapInfo::init_from_file(int fd) {
312 size_t sz = _header->data_size();
313 char* addr = _header->data();
314 size_t n = os::read(fd, addr, (unsigned int)sz);
315 if (n != sz) {
316 fail_continue("Unable to read the file header.");
317 return false;
318 }
319 if (_header->_version != current_version()) {
320 fail_continue("The shared archive file has the wrong version.");
321 return false;
322 }
323 _file_offset = (long)n;
324
325 size_t info_size = _header->_paths_misc_info_size;
326 _paths_misc_info = NEW_C_HEAP_ARRAY_RETURN_NULL(char, info_size, mtClass);
327 if (_paths_misc_info == NULL) {
328 fail_continue("Unable to read the file header.");
329 return false;
330 }
331 n = os::read(fd, _paths_misc_info, (unsigned int)info_size);
332 if (n != info_size) {
333 fail_continue("Unable to read the shared path info header.");
334 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
335 _paths_misc_info = NULL;
336 return false;
337 }
338
339 size_t len = lseek(fd, 0, SEEK_END);
340 struct FileMapInfo::FileMapHeader::space_info* si =
341 &_header->_space[MetaspaceShared::mc];
342 if (si->_file_offset >= len || len - si->_file_offset < si->_used) {
343 fail_continue("The shared archive file has been truncated.");
344 return false;
345 }
346
347 _file_offset += (long)n;
348 return true;
349 }
350
351
352 // Read the FileMapInfo information from the file.
353 bool FileMapInfo::open_for_read() {
354 _full_path = Arguments::GetSharedArchivePath();
355 int fd = open(_full_path, O_RDONLY | O_BINARY, 0);
356 if (fd < 0) {
357 if (errno == ENOENT) {
358 // Not locating the shared archive is ok.
359 fail_continue("Specified shared archive not found.");
360 } else {
361 fail_continue("Failed to open shared archive file (%s).",
362 strerror(errno));
363 }
364 return false;
365 }
366
367 _fd = fd;
368 _file_open = true;
369 return true;
370 }
371
372
373 // Write the FileMapInfo information to the file.
374
375 void FileMapInfo::open_for_write() {
376 _full_path = Arguments::GetSharedArchivePath();
377 if (PrintSharedSpaces) {
378 tty->print_cr("Dumping shared data to file: ");
379 tty->print_cr(" %s", _full_path);
380 }
381
382 #ifdef _WINDOWS // On Windows, need WRITE permission to remove the file.
383 chmod(_full_path, _S_IREAD | _S_IWRITE);
384 #endif
385
386 // Use remove() to delete the existing file because, on Unix, this will
387 // allow processes that have it open continued access to the file.
388 remove(_full_path);
389 int fd = open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444);
390 if (fd < 0) {
391 fail_stop("Unable to create shared archive file %s.", _full_path);
392 }
393 _fd = fd;
394 _file_offset = 0;
395 _file_open = true;
396 }
397
398
399 // Write the header to the file, seek to the next allocation boundary.
400
401 void FileMapInfo::write_header() {
402 int info_size = ClassLoader::get_shared_paths_misc_info_size();
403
404 _header->_paths_misc_info_size = info_size;
405
406 align_file_position();
407 size_t sz = _header->data_size();
408 char* addr = _header->data();
409 write_bytes(addr, (int)sz); // skip the C++ vtable
410 write_bytes(ClassLoader::get_shared_paths_misc_info(), info_size);
411 align_file_position();
412 }
413
414
415 // Dump shared spaces to file.
416
417 void FileMapInfo::write_space(int i, Metaspace* space, bool read_only) {
418 align_file_position();
419 size_t used = space->used_bytes_slow(Metaspace::NonClassType);
420 size_t capacity = space->capacity_bytes_slow(Metaspace::NonClassType);
421 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
422 write_region(i, (char*)space->bottom(), used, capacity, read_only, false);
423 }
424
425
426 // Dump region to file.
427
428 void FileMapInfo::write_region(int region, char* base, size_t size,
429 size_t capacity, bool read_only,
430 bool allow_exec) {
431 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[region];
432
433 if (_file_open) {
434 guarantee(si->_file_offset == _file_offset, "file offset mismatch.");
435 if (PrintSharedSpaces) {
436 tty->print_cr("Shared file region %d: 0x%6x bytes, addr " INTPTR_FORMAT
437 " file offset 0x%6x", region, size, base, _file_offset);
438 }
439 } else {
440 si->_file_offset = _file_offset;
441 }
442 si->_base = base;
443 si->_used = size;
444 si->_capacity = capacity;
445 si->_read_only = read_only;
446 si->_allow_exec = allow_exec;
447 si->_crc = ClassLoader::crc32(0, base, (jint)size);
448 write_bytes_aligned(base, (int)size);
449 }
450
451
452 // Dump bytes to file -- at the current file position.
453
454 void FileMapInfo::write_bytes(const void* buffer, int nbytes) {
455 if (_file_open) {
456 int n = ::write(_fd, buffer, nbytes);
457 if (n != nbytes) {
458 // It is dangerous to leave the corrupted shared archive file around,
459 // close and remove the file. See bug 6372906.
460 close();
461 remove(_full_path);
462 fail_stop("Unable to write to shared archive file.");
463 }
464 }
465 _file_offset += nbytes;
466 }
467
468
469 // Align file position to an allocation unit boundary.
470
471 void FileMapInfo::align_file_position() {
472 size_t new_file_offset = align_size_up(_file_offset,
473 os::vm_allocation_granularity());
474 if (new_file_offset != _file_offset) {
475 _file_offset = new_file_offset;
476 if (_file_open) {
477 // Seek one byte back from the target and write a byte to insure
478 // that the written file is the correct length.
479 _file_offset -= 1;
480 if (lseek(_fd, (long)_file_offset, SEEK_SET) < 0) {
481 fail_stop("Unable to seek.");
482 }
483 char zero = 0;
484 write_bytes(&zero, 1);
485 }
486 }
487 }
488
489
490 // Dump bytes to file -- at the current file position.
491
492 void FileMapInfo::write_bytes_aligned(const void* buffer, int nbytes) {
493 align_file_position();
494 write_bytes(buffer, nbytes);
495 align_file_position();
496 }
497
498
499 // Close the shared archive file. This does NOT unmap mapped regions.
500
501 void FileMapInfo::close() {
502 if (_file_open) {
503 if (::close(_fd) < 0) {
504 fail_stop("Unable to close the shared archive file.");
505 }
506 _file_open = false;
507 _fd = -1;
508 }
509 }
510
511
512 // JVM/TI RedefineClasses() support:
513 // Remap the shared readonly space to shared readwrite, private.
514 bool FileMapInfo::remap_shared_readonly_as_readwrite() {
515 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[0];
516 if (!si->_read_only) {
517 // the space is already readwrite so we are done
518 return true;
519 }
520 size_t used = si->_used;
521 size_t size = align_size_up(used, os::vm_allocation_granularity());
522 if (!open_for_read()) {
523 return false;
524 }
525 char *base = os::remap_memory(_fd, _full_path, si->_file_offset,
526 si->_base, size, false /* !read_only */,
527 si->_allow_exec);
528 close();
529 if (base == NULL) {
530 fail_continue("Unable to remap shared readonly space (errno=%d).", errno);
531 return false;
532 }
533 if (base != si->_base) {
534 fail_continue("Unable to remap shared readonly space at required address.");
535 return false;
536 }
537 si->_read_only = false;
538 return true;
539 }
540
541 // Map the whole region at once, assumed to be allocated contiguously.
542 ReservedSpace FileMapInfo::reserve_shared_memory() {
543 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[0];
544 char* requested_addr = si->_base;
545
546 size_t size = FileMapInfo::shared_spaces_size();
547
548 // Reserve the space first, then map otherwise map will go right over some
549 // other reserved memory (like the code cache).
550 ReservedSpace rs(size, os::vm_allocation_granularity(), false, requested_addr);
551 if (!rs.is_reserved()) {
552 fail_continue("Unable to reserve shared space at required address " INTPTR_FORMAT, requested_addr);
553 return rs;
554 }
555 // the reserved virtual memory is for mapping class data sharing archive
556 MemTracker::record_virtual_memory_type((address)rs.base(), mtClassShared);
557
558 return rs;
559 }
560
561 // Memory map a region in the address space.
562 static const char* shared_region_name[] = { "ReadOnly", "ReadWrite", "MiscData", "MiscCode"};
563
564 char* FileMapInfo::map_region(int i) {
565 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
566 size_t used = si->_used;
567 size_t alignment = os::vm_allocation_granularity();
568 size_t size = align_size_up(used, alignment);
569 char *requested_addr = si->_base;
570
571 // map the contents of the CDS archive in this memory
572 char *base = os::map_memory(_fd, _full_path, si->_file_offset,
573 requested_addr, size, si->_read_only,
574 si->_allow_exec);
575 if (base == NULL || base != si->_base) {
576 fail_continue("Unable to map %s shared space at required address.", shared_region_name[i]);
577 return NULL;
578 }
579 #ifdef _WINDOWS
580 // This call is Windows-only because the memory_type gets recorded for the other platforms
581 // in method FileMapInfo::reserve_shared_memory(), which is not called on Windows.
582 MemTracker::record_virtual_memory_type((address)base, mtClassShared);
583 #endif
584 return base;
585 }
586
587 bool FileMapInfo::verify_region_checksum(int i) {
588 if (!VerifySharedSpaces) {
589 return true;
590 }
591 const char* buf = _header->_space[i]._base;
592 size_t sz = _header->_space[i]._used;
593 int crc = ClassLoader::crc32(0, buf, (jint)sz);
594 if (crc != _header->_space[i]._crc) {
595 fail_continue("Checksum verification failed.");
596 return false;
597 }
598 return true;
599 }
600
601 // Unmap a memory region in the address space.
602
603 void FileMapInfo::unmap_region(int i) {
604 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
605 size_t used = si->_used;
606 size_t size = align_size_up(used, os::vm_allocation_granularity());
607 if (!os::unmap_memory(si->_base, size)) {
608 fail_stop("Unable to unmap shared space.");
609 }
610 }
611
612
613 void FileMapInfo::assert_mark(bool check) {
614 if (!check) {
615 fail_stop("Mark mismatch while restoring from shared file.");
616 }
617 }
618
619
620 FileMapInfo* FileMapInfo::_current_info = NULL;
621 SharedClassPathEntry* FileMapInfo::_classpath_entry_table = NULL;
622 int FileMapInfo::_classpath_entry_table_size = 0;
623 size_t FileMapInfo::_classpath_entry_size = 0x1234baad;
624 bool FileMapInfo::_validating_classpath_entry_table = false;
625
626 // Open the shared archive file, read and validate the header
627 // information (version, boot classpath, etc.). If initialization
628 // fails, shared spaces are disabled and the file is closed. [See
629 // fail_continue.]
630 //
631 // Validation of the archive is done in two steps:
632 //
633 // [1] validate_header() - done here. This checks the header, including _paths_misc_info.
634 // [2] validate_classpath_entry_table - this is done later, because the table is in the RW
635 // region of the archive, which is not mapped yet.
636 bool FileMapInfo::initialize() {
637 assert(UseSharedSpaces, "UseSharedSpaces expected.");
638
639 if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space()) {
640 fail_continue("Tool agent requires sharing to be disabled.");
641 return false;
642 }
643
644 if (!open_for_read()) {
645 return false;
646 }
647
648 init_from_file(_fd);
649 if (!validate_header()) {
650 return false;
651 }
652
653 SharedReadOnlySize = _header->_space[0]._capacity;
654 SharedReadWriteSize = _header->_space[1]._capacity;
655 SharedMiscDataSize = _header->_space[2]._capacity;
656 SharedMiscCodeSize = _header->_space[3]._capacity;
657 return true;
658 }
659
660 int FileMapInfo::FileMapHeader::compute_crc() {
661 char* header = data();
662 // start computing from the field after _crc
663 char* buf = (char*)&_crc + sizeof(int);
664 size_t sz = data_size() - (buf - header);
665 int crc = ClassLoader::crc32(0, buf, (jint)sz);
666 return crc;
667 }
668
669 bool FileMapInfo::FileMapHeader::validate() {
670 if (VerifySharedSpaces && compute_crc() != _crc) {
671 fail_continue("Header checksum verification failed.");
672 return false;
673 }
674
675 if (_version != current_version()) {
676 FileMapInfo::fail_continue("The shared archive file is the wrong version.");
677 return false;
678 }
679 if (_magic != (int)0xf00baba2) {
680 FileMapInfo::fail_continue("The shared archive file has a bad magic number.");
681 return false;
682 }
683 char header_version[JVM_IDENT_MAX];
684 get_header_version(header_version);
685 if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) {
686 if (TraceClassPaths) {
687 tty->print_cr("Expected: %s", header_version);
688 tty->print_cr("Actual: %s", _jvm_ident);
689 }
690 FileMapInfo::fail_continue("The shared archive file was created by a different"
691 " version or build of HotSpot");
692 return false;
693 }
694 if (_obj_alignment != ObjectAlignmentInBytes) {
695 FileMapInfo::fail_continue("The shared archive file's ObjectAlignmentInBytes of %d"
696 " does not equal the current ObjectAlignmentInBytes of %d.",
697 _obj_alignment, ObjectAlignmentInBytes);
698 return false;
699 }
700
701 return true;
702 }
703
704 bool FileMapInfo::validate_header() {
705 bool status = _header->validate();
706
707 if (status) {
708 if (!ClassLoader::check_shared_paths_misc_info(_paths_misc_info, _header->_paths_misc_info_size)) {
709 if (!PrintSharedArchiveAndExit) {
710 fail_continue("shared class paths mismatch (hint: enable -XX:+TraceClassPaths to diagnose the failure)");
711 status = false;
712 }
713 }
714 }
715
716 if (_paths_misc_info != NULL) {
717 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
718 _paths_misc_info = NULL;
719 }
720 return status;
721 }
722
723 // The following method is provided to see whether a given pointer
724 // falls in the mapped shared space.
725 // Param:
726 // p, The given pointer
727 // Return:
728 // True if the p is within the mapped shared space, otherwise, false.
729 bool FileMapInfo::is_in_shared_space(const void* p) {
730 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
731 if (p >= _header->_space[i]._base &&
732 p < _header->_space[i]._base + _header->_space[i]._used) {
733 return true;
734 }
735 }
736
737 return false;
738 }
739
740 void FileMapInfo::print_shared_spaces() {
741 gclog_or_tty->print_cr("Shared Spaces:");
742 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
743 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
744 gclog_or_tty->print(" %s " INTPTR_FORMAT "-" INTPTR_FORMAT,
745 shared_region_name[i],
746 si->_base, si->_base + si->_used);
747 }
748 }
749
750 // Unmap mapped regions of shared space.
751 void FileMapInfo::stop_sharing_and_unmap(const char* msg) {
752 FileMapInfo *map_info = FileMapInfo::current_info();
753 if (map_info) {
754 map_info->fail_continue("%s", msg);
755 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
756 if (map_info->_header->_space[i]._base != NULL) {
757 map_info->unmap_region(i);
758 map_info->_header->_space[i]._base = NULL;
759 }
760 }
761 } else if (DumpSharedSpaces) {
762 fail_stop("%s", msg);
763 }
764 }