1 /*
2 * Copyright (c) 2003, 2015, 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: %s.", _full_path,
392 strerror(errno));
393 }
394 _fd = fd;
395 _file_offset = 0;
396 _file_open = true;
397 }
398
399
400 // Write the header to the file, seek to the next allocation boundary.
401
402 void FileMapInfo::write_header() {
403 int info_size = ClassLoader::get_shared_paths_misc_info_size();
404
405 _header->_paths_misc_info_size = info_size;
406
407 align_file_position();
408 size_t sz = _header->data_size();
409 char* addr = _header->data();
410 write_bytes(addr, (int)sz); // skip the C++ vtable
411 write_bytes(ClassLoader::get_shared_paths_misc_info(), info_size);
412 align_file_position();
413 }
414
415
416 // Dump shared spaces to file.
417
418 void FileMapInfo::write_space(int i, Metaspace* space, bool read_only) {
419 align_file_position();
420 size_t used = space->used_bytes_slow(Metaspace::NonClassType);
421 size_t capacity = space->capacity_bytes_slow(Metaspace::NonClassType);
422 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
423 write_region(i, (char*)space->bottom(), used, capacity, read_only, false);
424 }
425
426
427 // Dump region to file.
428
429 void FileMapInfo::write_region(int region, char* base, size_t size,
430 size_t capacity, bool read_only,
431 bool allow_exec) {
432 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[region];
433
434 if (_file_open) {
435 guarantee(si->_file_offset == _file_offset, "file offset mismatch.");
436 if (PrintSharedSpaces) {
437 tty->print_cr("Shared file region %d: 0x%6x bytes, addr " INTPTR_FORMAT
438 " file offset 0x%6x", region, size, base, _file_offset);
439 }
440 } else {
441 si->_file_offset = _file_offset;
442 }
443 si->_base = base;
444 si->_used = size;
445 si->_capacity = capacity;
446 si->_read_only = read_only;
447 si->_allow_exec = allow_exec;
448 si->_crc = ClassLoader::crc32(0, base, (jint)size);
449 write_bytes_aligned(base, (int)size);
450 }
451
452
453 // Dump bytes to file -- at the current file position.
454
455 void FileMapInfo::write_bytes(const void* buffer, int nbytes) {
456 if (_file_open) {
457 int n = ::write(_fd, buffer, nbytes);
458 if (n != nbytes) {
459 // It is dangerous to leave the corrupted shared archive file around,
460 // close and remove the file. See bug 6372906.
461 close();
462 remove(_full_path);
463 fail_stop("Unable to write to shared archive file.");
464 }
465 }
466 _file_offset += nbytes;
467 }
468
469
470 // Align file position to an allocation unit boundary.
471
472 void FileMapInfo::align_file_position() {
473 size_t new_file_offset = align_size_up(_file_offset,
474 os::vm_allocation_granularity());
475 if (new_file_offset != _file_offset) {
476 _file_offset = new_file_offset;
477 if (_file_open) {
478 // Seek one byte back from the target and write a byte to insure
479 // that the written file is the correct length.
480 _file_offset -= 1;
481 if (lseek(_fd, (long)_file_offset, SEEK_SET) < 0) {
482 fail_stop("Unable to seek.");
483 }
484 char zero = 0;
485 write_bytes(&zero, 1);
486 }
487 }
488 }
489
490
491 // Dump bytes to file -- at the current file position.
492
493 void FileMapInfo::write_bytes_aligned(const void* buffer, int nbytes) {
494 align_file_position();
495 write_bytes(buffer, nbytes);
496 align_file_position();
497 }
498
499
500 // Close the shared archive file. This does NOT unmap mapped regions.
501
502 void FileMapInfo::close() {
503 if (_file_open) {
504 if (::close(_fd) < 0) {
505 fail_stop("Unable to close the shared archive file.");
506 }
507 _file_open = false;
508 _fd = -1;
509 }
510 }
511
512
513 // JVM/TI RedefineClasses() support:
514 // Remap the shared readonly space to shared readwrite, private.
515 bool FileMapInfo::remap_shared_readonly_as_readwrite() {
516 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[0];
517 if (!si->_read_only) {
518 // the space is already readwrite so we are done
519 return true;
520 }
521 size_t used = si->_used;
522 size_t size = align_size_up(used, os::vm_allocation_granularity());
523 if (!open_for_read()) {
524 return false;
525 }
526 char *base = os::remap_memory(_fd, _full_path, si->_file_offset,
527 si->_base, size, false /* !read_only */,
528 si->_allow_exec);
529 close();
530 if (base == NULL) {
531 fail_continue("Unable to remap shared readonly space (errno=%d).", errno);
532 return false;
533 }
534 if (base != si->_base) {
535 fail_continue("Unable to remap shared readonly space at required address.");
536 return false;
537 }
538 si->_read_only = false;
539 return true;
540 }
541
542 // Map the whole region at once, assumed to be allocated contiguously.
543 ReservedSpace FileMapInfo::reserve_shared_memory() {
544 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[0];
545 char* requested_addr = si->_base;
546
547 size_t size = FileMapInfo::shared_spaces_size();
548
549 // Reserve the space first, then map otherwise map will go right over some
550 // other reserved memory (like the code cache).
551 ReservedSpace rs(size, os::vm_allocation_granularity(), false, requested_addr);
552 if (!rs.is_reserved()) {
553 fail_continue("Unable to reserve shared space at required address " INTPTR_FORMAT, requested_addr);
554 return rs;
555 }
556 // the reserved virtual memory is for mapping class data sharing archive
557 MemTracker::record_virtual_memory_type((address)rs.base(), mtClassShared);
558
559 return rs;
560 }
561
562 // Memory map a region in the address space.
563 static const char* shared_region_name[] = { "ReadOnly", "ReadWrite", "MiscData", "MiscCode"};
564
565 char* FileMapInfo::map_region(int i) {
566 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
567 size_t used = si->_used;
568 size_t alignment = os::vm_allocation_granularity();
569 size_t size = align_size_up(used, alignment);
570 char *requested_addr = si->_base;
571
572 // map the contents of the CDS archive in this memory
573 char *base = os::map_memory(_fd, _full_path, si->_file_offset,
574 requested_addr, size, si->_read_only,
575 si->_allow_exec);
576 if (base == NULL || base != si->_base) {
577 fail_continue("Unable to map %s shared space at required address.", shared_region_name[i]);
578 return NULL;
579 }
580 #ifdef _WINDOWS
581 // This call is Windows-only because the memory_type gets recorded for the other platforms
582 // in method FileMapInfo::reserve_shared_memory(), which is not called on Windows.
583 MemTracker::record_virtual_memory_type((address)base, mtClassShared);
584 #endif
585 return base;
586 }
587
588 bool FileMapInfo::verify_region_checksum(int i) {
589 if (!VerifySharedSpaces) {
590 return true;
591 }
592 const char* buf = _header->_space[i]._base;
593 size_t sz = _header->_space[i]._used;
594 int crc = ClassLoader::crc32(0, buf, (jint)sz);
595 if (crc != _header->_space[i]._crc) {
596 fail_continue("Checksum verification failed.");
597 return false;
598 }
599 return true;
600 }
601
602 // Unmap a memory region in the address space.
603
604 void FileMapInfo::unmap_region(int i) {
605 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
606 size_t used = si->_used;
607 size_t size = align_size_up(used, os::vm_allocation_granularity());
608 if (!os::unmap_memory(si->_base, size)) {
609 fail_stop("Unable to unmap shared space.");
610 }
611 }
612
613
614 void FileMapInfo::assert_mark(bool check) {
615 if (!check) {
616 fail_stop("Mark mismatch while restoring from shared file.");
617 }
618 }
619
620
621 FileMapInfo* FileMapInfo::_current_info = NULL;
622 SharedClassPathEntry* FileMapInfo::_classpath_entry_table = NULL;
623 int FileMapInfo::_classpath_entry_table_size = 0;
624 size_t FileMapInfo::_classpath_entry_size = 0x1234baad;
625 bool FileMapInfo::_validating_classpath_entry_table = false;
626
627 // Open the shared archive file, read and validate the header
628 // information (version, boot classpath, etc.). If initialization
629 // fails, shared spaces are disabled and the file is closed. [See
630 // fail_continue.]
631 //
632 // Validation of the archive is done in two steps:
633 //
634 // [1] validate_header() - done here. This checks the header, including _paths_misc_info.
635 // [2] validate_classpath_entry_table - this is done later, because the table is in the RW
636 // region of the archive, which is not mapped yet.
637 bool FileMapInfo::initialize() {
638 assert(UseSharedSpaces, "UseSharedSpaces expected.");
639
640 if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space()) {
641 fail_continue("Tool agent requires sharing to be disabled.");
642 return false;
643 }
644
645 if (!open_for_read()) {
646 return false;
647 }
648
649 init_from_file(_fd);
650 if (!validate_header()) {
651 return false;
652 }
653
654 SharedReadOnlySize = _header->_space[0]._capacity;
655 SharedReadWriteSize = _header->_space[1]._capacity;
656 SharedMiscDataSize = _header->_space[2]._capacity;
657 SharedMiscCodeSize = _header->_space[3]._capacity;
658 return true;
659 }
660
661 int FileMapInfo::FileMapHeader::compute_crc() {
662 char* header = data();
663 // start computing from the field after _crc
664 char* buf = (char*)&_crc + sizeof(int);
665 size_t sz = data_size() - (buf - header);
666 int crc = ClassLoader::crc32(0, buf, (jint)sz);
667 return crc;
668 }
669
670 bool FileMapInfo::FileMapHeader::validate() {
671 if (VerifySharedSpaces && compute_crc() != _crc) {
672 fail_continue("Header checksum verification failed.");
673 return false;
674 }
675
676 if (_version != current_version()) {
677 FileMapInfo::fail_continue("The shared archive file is the wrong version.");
678 return false;
679 }
680 if (_magic != (int)0xf00baba2) {
681 FileMapInfo::fail_continue("The shared archive file has a bad magic number.");
682 return false;
683 }
684 char header_version[JVM_IDENT_MAX];
685 get_header_version(header_version);
686 if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) {
687 if (TraceClassPaths) {
688 tty->print_cr("Expected: %s", header_version);
689 tty->print_cr("Actual: %s", _jvm_ident);
690 }
691 FileMapInfo::fail_continue("The shared archive file was created by a different"
692 " version or build of HotSpot");
693 return false;
694 }
695 if (_obj_alignment != ObjectAlignmentInBytes) {
696 FileMapInfo::fail_continue("The shared archive file's ObjectAlignmentInBytes of %d"
697 " does not equal the current ObjectAlignmentInBytes of %d.",
698 _obj_alignment, ObjectAlignmentInBytes);
699 return false;
700 }
701
702 return true;
703 }
704
705 bool FileMapInfo::validate_header() {
706 bool status = _header->validate();
707
708 if (status) {
709 if (!ClassLoader::check_shared_paths_misc_info(_paths_misc_info, _header->_paths_misc_info_size)) {
710 if (!PrintSharedArchiveAndExit) {
711 fail_continue("shared class paths mismatch (hint: enable -XX:+TraceClassPaths to diagnose the failure)");
712 status = false;
713 }
714 }
715 }
716
717 if (_paths_misc_info != NULL) {
718 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
719 _paths_misc_info = NULL;
720 }
721 return status;
722 }
723
724 // The following method is provided to see whether a given pointer
725 // falls in the mapped shared space.
726 // Param:
727 // p, The given pointer
728 // Return:
729 // True if the p is within the mapped shared space, otherwise, false.
730 bool FileMapInfo::is_in_shared_space(const void* p) {
731 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
732 if (p >= _header->_space[i]._base &&
733 p < _header->_space[i]._base + _header->_space[i]._used) {
734 return true;
735 }
736 }
737
738 return false;
739 }
740
741 void FileMapInfo::print_shared_spaces() {
742 gclog_or_tty->print_cr("Shared Spaces:");
743 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
744 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
745 gclog_or_tty->print(" %s " INTPTR_FORMAT "-" INTPTR_FORMAT,
746 shared_region_name[i],
747 si->_base, si->_base + si->_used);
748 }
749 }
750
751 // Unmap mapped regions of shared space.
752 void FileMapInfo::stop_sharing_and_unmap(const char* msg) {
753 FileMapInfo *map_info = FileMapInfo::current_info();
754 if (map_info) {
755 map_info->fail_continue("%s", msg);
756 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
757 if (map_info->_header->_space[i]._base != NULL) {
758 map_info->unmap_region(i);
759 map_info->_header->_space[i]._base = NULL;
760 }
761 }
762 } else if (DumpSharedSpaces) {
763 fail_stop("%s", msg);
764 }
765 }