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 #if INCLUDE_ALL_GCS
32 #include "gc/g1/g1CollectedHeap.hpp"
33 #endif
34 #include "memory/filemap.hpp"
35 #include "memory/metadataFactory.hpp"
36 #include "memory/oopFactory.hpp"
37 #include "oops/objArrayOop.hpp"
38 #include "prims/jvmtiExport.hpp"
39 #include "runtime/arguments.hpp"
40 #include "runtime/java.hpp"
41 #include "runtime/os.hpp"
42 #include "runtime/vm_version.hpp"
43 #include "services/memTracker.hpp"
44 #include "utilities/defaultStream.hpp"
45
46 # include <sys/stat.h>
47 # include <errno.h>
48
49 #ifndef O_BINARY // if defined (Win32) use binary files.
50 #define O_BINARY 0 // otherwise do nothing.
51 #endif
52
53 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
54 extern address JVM_FunctionAtStart();
55 extern address JVM_FunctionAtEnd();
56
57 // Complain and stop. All error conditions occurring during the writing of
58 // an archive file should stop the process. Unrecoverable errors during
59 // the reading of the archive file should stop the process.
60
61 static void fail(const char *msg, va_list ap) {
62 // This occurs very early during initialization: tty is not initialized.
63 jio_fprintf(defaultStream::error_stream(),
64 "An error has occurred while processing the"
65 " shared archive file.\n");
66 jio_vfprintf(defaultStream::error_stream(), msg, ap);
67 jio_fprintf(defaultStream::error_stream(), "\n");
68 // Do not change the text of the below message because some tests check for it.
69 vm_exit_during_initialization("Unable to use shared archive.", NULL);
70 }
71
72
73 void FileMapInfo::fail_stop(const char *msg, ...) {
74 va_list ap;
75 va_start(ap, msg);
76 fail(msg, ap); // Never returns.
77 va_end(ap); // for completeness.
78 }
79
80
81 // Complain and continue. Recoverable errors during the reading of the
82 // archive file may continue (with sharing disabled).
83 //
84 // If we continue, then disable shared spaces and close the file.
85
86 void FileMapInfo::fail_continue(const char *msg, ...) {
87 va_list ap;
88 va_start(ap, msg);
89 MetaspaceShared::set_archive_loading_failed();
90 if (PrintSharedArchiveAndExit && _validating_classpath_entry_table) {
91 // If we are doing PrintSharedArchiveAndExit and some of the classpath entries
92 // do not validate, we can still continue "limping" to validate the remaining
93 // entries. No need to quit.
94 tty->print("[");
95 tty->vprint(msg, ap);
96 tty->print_cr("]");
97 } else {
98 if (RequireSharedSpaces) {
99 fail(msg, ap);
100 } else {
101 if (PrintSharedSpaces) {
102 tty->print_cr("UseSharedSpaces: %s", msg);
103 }
104 }
105 UseSharedSpaces = false;
106 assert(current_info() != NULL, "singleton must be registered");
107 current_info()->close();
108 }
109 va_end(ap);
110 }
111
112 // Fill in the fileMapInfo structure with data about this VM instance.
113
114 // This method copies the vm version info into header_version. If the version is too
115 // long then a truncated version, which has a hash code appended to it, is copied.
116 //
117 // Using a template enables this method to verify that header_version is an array of
118 // length JVM_IDENT_MAX. This ensures that the code that writes to the CDS file and
119 // the code that reads the CDS file will both use the same size buffer. Hence, will
120 // use identical truncation. This is necessary for matching of truncated versions.
121 template <int N> static void get_header_version(char (&header_version) [N]) {
122 assert(N == JVM_IDENT_MAX, "Bad header_version size");
123
124 const char *vm_version = VM_Version::internal_vm_info_string();
125 const int version_len = (int)strlen(vm_version);
126
127 if (version_len < (JVM_IDENT_MAX-1)) {
128 strcpy(header_version, vm_version);
129
130 } else {
131 // Get the hash value. Use a static seed because the hash needs to return the same
132 // value over multiple jvm invocations.
133 unsigned int hash = AltHashing::murmur3_32(8191, (const jbyte*)vm_version, version_len);
134
135 // Truncate the ident, saving room for the 8 hex character hash value.
136 strncpy(header_version, vm_version, JVM_IDENT_MAX-9);
137
138 // Append the hash code as eight hex digits.
139 sprintf(&header_version[JVM_IDENT_MAX-9], "%08x", hash);
140 header_version[JVM_IDENT_MAX-1] = 0; // Null terminate.
141 }
142 }
143
144 FileMapInfo::FileMapInfo() {
145 assert(_current_info == NULL, "must be singleton"); // not thread safe
146 _current_info = this;
147 memset(this, 0, sizeof(FileMapInfo));
148 _file_offset = 0;
149 _file_open = false;
150 _header = SharedClassUtil::allocate_file_map_header();
151 _header->_version = _invalid_version;
152 }
153
154 FileMapInfo::~FileMapInfo() {
155 assert(_current_info == this, "must be singleton"); // not thread safe
156 _current_info = NULL;
157 }
158
159 void FileMapInfo::populate_header(size_t alignment) {
160 _header->populate(this, alignment);
161 }
162
163 size_t FileMapInfo::FileMapHeader::data_size() {
164 return SharedClassUtil::file_map_header_size() - sizeof(FileMapInfo::FileMapHeaderBase);
165 }
166
167 void FileMapInfo::FileMapHeader::populate(FileMapInfo* mapinfo, size_t alignment) {
168 _magic = 0xf00baba2;
169 _version = _current_version;
170 _alignment = alignment;
171 _obj_alignment = ObjectAlignmentInBytes;
172 _narrow_oop_mode = Universe::narrow_oop_mode();
173 _narrow_oop_shift = Universe::narrow_oop_shift();
174 _max_heap_size = MaxHeapSize;
175 _narrow_klass_base = Universe::narrow_klass_base();
176 _narrow_klass_shift = Universe::narrow_klass_shift();
177 _classpath_entry_table_size = mapinfo->_classpath_entry_table_size;
178 _classpath_entry_table = mapinfo->_classpath_entry_table;
179 _classpath_entry_size = mapinfo->_classpath_entry_size;
180
181 // The following fields are for sanity checks for whether this archive
182 // will function correctly with this JVM and the bootclasspath it's
183 // invoked with.
184
185 // JVM version string ... changes on each build.
186 get_header_version(_jvm_ident);
187 }
188
189 void FileMapInfo::allocate_classpath_entry_table() {
190 int bytes = 0;
191 int count = 0;
192 char* strptr = NULL;
193 char* strptr_max = NULL;
194 Thread* THREAD = Thread::current();
195
196 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
197 size_t entry_size = SharedClassUtil::shared_class_path_entry_size();
198
199 for (int pass=0; pass<2; pass++) {
200 ClassPathEntry *cpe = ClassLoader::classpath_entry(0);
201
202 for (int cur_entry = 0 ; cpe != NULL; cpe = cpe->next(), cur_entry++) {
203 const char *name = cpe->name();
204 int name_bytes = (int)(strlen(name) + 1);
205
206 if (pass == 0) {
207 count ++;
208 bytes += (int)entry_size;
209 bytes += name_bytes;
210 if (TraceClassPaths || (TraceClassLoading && Verbose)) {
211 tty->print_cr("[Add main shared path (%s) %s]", (cpe->is_jar_file() ? "jar" : "dir"), name);
212 }
213 } else {
214 SharedClassPathEntry* ent = shared_classpath(cur_entry);
215 if (cpe->is_jar_file()) {
216 struct stat st;
217 if (os::stat(name, &st) != 0) {
218 // The file/dir must exist, or it would not have been added
219 // into ClassLoader::classpath_entry().
220 //
221 // If we can't access a jar file in the boot path, then we can't
222 // make assumptions about where classes get loaded from.
223 FileMapInfo::fail_stop("Unable to open jar file %s.", name);
224 }
225
226 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error.
227 SharedClassUtil::update_shared_classpath(cpe, ent, st.st_mtime, st.st_size, THREAD);
228 } else {
229 struct stat st;
230 if ((os::stat(name, &st) == 0) && ((st.st_mode & S_IFDIR) == S_IFDIR)) {
231 if (!os::dir_is_empty(name)) {
232 ClassLoader::exit_with_path_failure("Cannot have non-empty directory in archived classpaths", name);
233 }
234 ent->_filesize = -1;
235 } else {
236 ent->_filesize = -2;
237 }
238 }
239 ent->_name = strptr;
240 if (strptr + name_bytes <= strptr_max) {
241 strncpy(strptr, name, (size_t)name_bytes); // name_bytes includes trailing 0.
242 strptr += name_bytes;
243 } else {
244 assert(0, "miscalculated buffer size");
245 }
246 }
247 }
248
249 if (pass == 0) {
250 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error.
251 Array<u8>* arr = MetadataFactory::new_array<u8>(loader_data, (bytes + 7)/8, THREAD);
252 strptr = (char*)(arr->data());
253 strptr_max = strptr + bytes;
254 SharedClassPathEntry* table = (SharedClassPathEntry*)strptr;
255 strptr += entry_size * count;
256
257 _classpath_entry_table_size = count;
258 _classpath_entry_table = table;
259 _classpath_entry_size = entry_size;
260 }
261 }
262 }
263
264 bool FileMapInfo::validate_classpath_entry_table() {
265 _validating_classpath_entry_table = true;
266
267 int count = _header->_classpath_entry_table_size;
268
269 _classpath_entry_table = _header->_classpath_entry_table;
270 _classpath_entry_size = _header->_classpath_entry_size;
271
272 for (int i=0; i<count; i++) {
273 SharedClassPathEntry* ent = shared_classpath(i);
274 struct stat st;
275 const char* name = ent->_name;
276 bool ok = true;
277 if (TraceClassPaths || (TraceClassLoading && Verbose)) {
278 tty->print_cr("[Checking shared classpath entry: %s]", name);
279 }
280 if (os::stat(name, &st) != 0) {
281 fail_continue("Required classpath entry does not exist: %s", name);
282 ok = false;
283 } else if (ent->is_dir()) {
284 if (!os::dir_is_empty(name)) {
285 fail_continue("directory is not empty: %s", name);
286 ok = false;
287 }
288 } else if (ent->is_jar()) {
289 if (ent->_timestamp != st.st_mtime ||
290 ent->_filesize != st.st_size) {
291 ok = false;
292 if (PrintSharedArchiveAndExit) {
293 fail_continue(ent->_timestamp != st.st_mtime ?
294 "Timestamp mismatch" :
295 "File size mismatch");
296 } else {
297 fail_continue("A jar file is not the one used while building"
298 " the shared archive file: %s", name);
299 }
300 }
301 }
302 if (ok) {
303 if (TraceClassPaths || (TraceClassLoading && Verbose)) {
304 tty->print_cr("[ok]");
305 }
306 } else if (!PrintSharedArchiveAndExit) {
307 _validating_classpath_entry_table = false;
308 return false;
309 }
310 }
311
312 _classpath_entry_table_size = _header->_classpath_entry_table_size;
313 _validating_classpath_entry_table = false;
314 return true;
315 }
316
317
318 // Read the FileMapInfo information from the file.
319
320 bool FileMapInfo::init_from_file(int fd) {
321 size_t sz = _header->data_size();
322 char* addr = _header->data();
323 size_t n = os::read(fd, addr, (unsigned int)sz);
324 if (n != sz) {
325 fail_continue("Unable to read the file header.");
326 return false;
327 }
328 if (_header->_version != current_version()) {
329 fail_continue("The shared archive file has the wrong version.");
330 return false;
331 }
332 _file_offset = (long)n;
333
334 size_t info_size = _header->_paths_misc_info_size;
335 _paths_misc_info = NEW_C_HEAP_ARRAY_RETURN_NULL(char, info_size, mtClass);
336 if (_paths_misc_info == NULL) {
337 fail_continue("Unable to read the file header.");
338 return false;
339 }
340 n = os::read(fd, _paths_misc_info, (unsigned int)info_size);
341 if (n != info_size) {
342 fail_continue("Unable to read the shared path info header.");
343 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
344 _paths_misc_info = NULL;
345 return false;
346 }
347
348 size_t len = lseek(fd, 0, SEEK_END);
349 struct FileMapInfo::FileMapHeader::space_info* si =
350 &_header->_space[MetaspaceShared::mc];
351 if (si->_file_offset >= len || len - si->_file_offset < si->_used) {
352 fail_continue("The shared archive file has been truncated.");
353 return false;
354 }
355
356 _file_offset += (long)n;
357 return true;
358 }
359
360
361 // Read the FileMapInfo information from the file.
362 bool FileMapInfo::open_for_read() {
363 _full_path = Arguments::GetSharedArchivePath();
364 int fd = open(_full_path, O_RDONLY | O_BINARY, 0);
365 if (fd < 0) {
366 if (errno == ENOENT) {
367 // Not locating the shared archive is ok.
368 fail_continue("Specified shared archive not found.");
369 } else {
370 fail_continue("Failed to open shared archive file (%s).",
371 strerror(errno));
372 }
373 return false;
374 }
375
376 _fd = fd;
377 _file_open = true;
378 return true;
379 }
380
381
382 // Write the FileMapInfo information to the file.
383
384 void FileMapInfo::open_for_write() {
385 _full_path = Arguments::GetSharedArchivePath();
386 if (PrintSharedSpaces) {
387 tty->print_cr("Dumping shared data to file: ");
388 tty->print_cr(" %s", _full_path);
389 }
390
391 #ifdef _WINDOWS // On Windows, need WRITE permission to remove the file.
392 chmod(_full_path, _S_IREAD | _S_IWRITE);
393 #endif
394
395 // Use remove() to delete the existing file because, on Unix, this will
396 // allow processes that have it open continued access to the file.
397 remove(_full_path);
398 int fd = open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444);
399 if (fd < 0) {
400 fail_stop("Unable to create shared archive file %s: (%s).", _full_path,
401 strerror(errno));
402 }
403 _fd = fd;
404 _file_offset = 0;
405 _file_open = true;
406 }
407
408
409 // Write the header to the file, seek to the next allocation boundary.
410
411 void FileMapInfo::write_header() {
412 int info_size = ClassLoader::get_shared_paths_misc_info_size();
413
414 _header->_paths_misc_info_size = info_size;
415
416 align_file_position();
417 size_t sz = _header->data_size();
418 char* addr = _header->data();
419 write_bytes(addr, (int)sz); // skip the C++ vtable
420 write_bytes(ClassLoader::get_shared_paths_misc_info(), info_size);
421 align_file_position();
422 }
423
424
425 // Dump shared spaces to file.
426
427 void FileMapInfo::write_space(int i, Metaspace* space, bool read_only) {
428 align_file_position();
429 size_t used = space->used_bytes_slow(Metaspace::NonClassType);
430 size_t capacity = space->capacity_bytes_slow(Metaspace::NonClassType);
431 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
432 write_region(i, (char*)space->bottom(), used, capacity, read_only, false);
433 }
434
435
436 // Dump region to file.
437
438 void FileMapInfo::write_region(int region, char* base, size_t size,
439 size_t capacity, bool read_only,
440 bool allow_exec) {
441 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[region];
442
443 if (_file_open) {
444 guarantee(si->_file_offset == _file_offset, "file offset mismatch.");
445 if (PrintSharedSpaces) {
446 tty->print_cr("Shared file region %d: 0x%6x bytes, addr " INTPTR_FORMAT
447 " file offset 0x%6x", region, size, base, _file_offset);
448 }
449 } else {
450 si->_file_offset = _file_offset;
451 }
452 if (MetaspaceShared::is_string_region(region)) {
453 assert((base - (char*)Universe::narrow_oop_base()) % HeapWordSize == 0, "Sanity");
454 if (base != NULL) {
455 si->_addr._offset = (intx)oopDesc::encode_heap_oop_not_null((oop)base);
456 } else {
457 si->_addr._offset = 0;
458 }
459 } else {
460 si->_addr._base = base;
461 }
462 si->_used = size;
463 si->_capacity = capacity;
464 si->_read_only = read_only;
465 si->_allow_exec = allow_exec;
466 si->_crc = ClassLoader::crc32(0, base, (jint)size);
467 write_bytes_aligned(base, (int)size);
468 }
469
470 // Write the string space. The string space contains one or multiple GC(G1) regions.
471 // When the total string space size is smaller than one GC region of the dump time,
472 // only one string region is used for shared strings.
473 //
474 // If the total string space size is bigger than one GC region, there would be more
475 // than one GC regions allocated for shared strings. The first/bottom GC region might
476 // be a partial GC region with the empty portion at the higher address within that region.
477 // The non-empty portion of the first region is written into the archive as one string
478 // region. The rest are consecutive full GC regions if they exist, which can be written
479 // out in one chunk as another string region.
480 void FileMapInfo::write_string_regions(GrowableArray<MemRegion> *regions) {
481 for (int i = MetaspaceShared::first_string;
482 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
483 char* start = NULL;
484 size_t size = 0;
485 if (regions->is_nonempty()) {
486 if (i == MetaspaceShared::first_string) {
487 MemRegion first = regions->first();
488 start = (char*)first.start();
489 size = first.byte_size();
490 } else {
491 int len = regions->length();
492 if (len > 1) {
493 start = (char*)regions->at(1).start();
494 size = (char*)regions->at(len - 1).end() - start;
495 }
496 }
497 }
498 write_region(i, start, size, size, false, false);
499 }
500 }
501
502
503 // Dump bytes to file -- at the current file position.
504
505 void FileMapInfo::write_bytes(const void* buffer, int nbytes) {
506 if (_file_open) {
507 int n = ::write(_fd, buffer, nbytes);
508 if (n != nbytes) {
509 // It is dangerous to leave the corrupted shared archive file around,
510 // close and remove the file. See bug 6372906.
511 close();
512 remove(_full_path);
513 fail_stop("Unable to write to shared archive file.");
514 }
515 }
516 _file_offset += nbytes;
517 }
518
519
520 // Align file position to an allocation unit boundary.
521
522 void FileMapInfo::align_file_position() {
523 size_t new_file_offset = align_size_up(_file_offset,
524 os::vm_allocation_granularity());
525 if (new_file_offset != _file_offset) {
526 _file_offset = new_file_offset;
527 if (_file_open) {
528 // Seek one byte back from the target and write a byte to insure
529 // that the written file is the correct length.
530 _file_offset -= 1;
531 if (lseek(_fd, (long)_file_offset, SEEK_SET) < 0) {
532 fail_stop("Unable to seek.");
533 }
534 char zero = 0;
535 write_bytes(&zero, 1);
536 }
537 }
538 }
539
540
541 // Dump bytes to file -- at the current file position.
542
543 void FileMapInfo::write_bytes_aligned(const void* buffer, int nbytes) {
544 align_file_position();
545 write_bytes(buffer, nbytes);
546 align_file_position();
547 }
548
549
550 // Close the shared archive file. This does NOT unmap mapped regions.
551
552 void FileMapInfo::close() {
553 if (_file_open) {
554 if (::close(_fd) < 0) {
555 fail_stop("Unable to close the shared archive file.");
556 }
557 _file_open = false;
558 _fd = -1;
559 }
560 }
561
562
563 // JVM/TI RedefineClasses() support:
564 // Remap the shared readonly space to shared readwrite, private.
565 bool FileMapInfo::remap_shared_readonly_as_readwrite() {
566 int idx = 0;
567 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[idx];
568 if (!si->_read_only) {
569 // the space is already readwrite so we are done
570 return true;
571 }
572 size_t used = si->_used;
573 size_t size = align_size_up(used, os::vm_allocation_granularity());
574 if (!open_for_read()) {
575 return false;
576 }
577 char *addr = _header->region_addr(idx);
578 char *base = os::remap_memory(_fd, _full_path, si->_file_offset,
579 addr, size, false /* !read_only */,
580 si->_allow_exec);
581 close();
582 if (base == NULL) {
583 fail_continue("Unable to remap shared readonly space (errno=%d).", errno);
584 return false;
585 }
586 if (base != addr) {
587 fail_continue("Unable to remap shared readonly space at required address.");
588 return false;
589 }
590 si->_read_only = false;
591 return true;
592 }
593
594 // Map the whole region at once, assumed to be allocated contiguously.
595 ReservedSpace FileMapInfo::reserve_shared_memory() {
596 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[0];
597 char* requested_addr = _header->region_addr(0);
598
599 size_t size = FileMapInfo::shared_spaces_size();
600
601 // Reserve the space first, then map otherwise map will go right over some
602 // other reserved memory (like the code cache).
603 ReservedSpace rs(size, os::vm_allocation_granularity(), false, requested_addr);
604 if (!rs.is_reserved()) {
605 fail_continue("Unable to reserve shared space at required address " INTPTR_FORMAT, requested_addr);
606 return rs;
607 }
608 // the reserved virtual memory is for mapping class data sharing archive
609 MemTracker::record_virtual_memory_type((address)rs.base(), mtClassShared);
610
611 return rs;
612 }
613
614 // Memory map a region in the address space.
615 static const char* shared_region_name[] = { "ReadOnly", "ReadWrite", "MiscData", "MiscCode",
616 "String1", "String2" };
617
618 char* FileMapInfo::map_region(int i) {
619 assert(!MetaspaceShared::is_string_region(i), "sanity");
620 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
621 size_t used = si->_used;
622 size_t alignment = os::vm_allocation_granularity();
623 size_t size = align_size_up(used, alignment);
624 char *requested_addr = _header->region_addr(i);
625
626 // If a tool agent is in use (debugging enabled), we must map the address space RW
627 if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space()) {
628 si->_read_only = false;
629 }
630
631 // map the contents of the CDS archive in this memory
632 char *base = os::map_memory(_fd, _full_path, si->_file_offset,
633 requested_addr, size, si->_read_only,
634 si->_allow_exec);
635 if (base == NULL || base != requested_addr) {
636 fail_continue("Unable to map %s shared space at required address.", shared_region_name[i]);
637 return NULL;
638 }
639 #ifdef _WINDOWS
640 // This call is Windows-only because the memory_type gets recorded for the other platforms
641 // in method FileMapInfo::reserve_shared_memory(), which is not called on Windows.
642 MemTracker::record_virtual_memory_type((address)base, mtClassShared);
643 #endif
644
645 return base;
646 }
647
648 static MemRegion *string_ranges = NULL;
649 static int num_ranges = 0;
650 bool FileMapInfo::map_string_regions() {
651 #if INCLUDE_ALL_GCS
652 if (UseG1GC && UseCompressedOops && UseCompressedClassPointers) {
653 // Check that all the narrow oop and klass encodings match the archive
654 if (narrow_oop_mode() != Universe::narrow_oop_mode() ||
655 narrow_oop_shift() != Universe::narrow_oop_shift() ||
656 narrow_klass_base() != Universe::narrow_klass_base() ||
657 narrow_klass_shift() != Universe::narrow_klass_shift()) {
658 if (PrintSharedSpaces && _header->_space[MetaspaceShared::first_string]._used > 0) {
659 tty->print_cr("Shared string data from the CDS archive is being ignored. "
660 "The current CompressedOops/CompressedClassPointers encoding differs from "
661 "that archived due to heap size change. The archive was dumped using max heap "
662 "size %dM.", max_heap_size()/M);
663 }
664 } else {
665 string_ranges = new MemRegion[MetaspaceShared::max_strings];
666 struct FileMapInfo::FileMapHeader::space_info* si;
667
668 for (int i = MetaspaceShared::first_string;
669 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
670 si = &_header->_space[i];
671 size_t used = si->_used;
672 if (used > 0) {
673 size_t size = used;
674 char* requested_addr = (char*)((void*)oopDesc::decode_heap_oop_not_null(
675 (narrowOop)si->_addr._offset));
676 string_ranges[num_ranges] = MemRegion((HeapWord*)requested_addr, size / HeapWordSize);
677 num_ranges ++;
678 }
679 }
680
681 if (num_ranges == 0) {
682 StringTable::ignore_shared_strings(true);
683 return true; // no shared string data
684 }
685
686 // Check that ranges are within the java heap
687 if (!G1CollectedHeap::heap()->check_archive_addresses(string_ranges, num_ranges)) {
688 fail_continue("Unable to allocate shared string space: range is not "
689 "within java heap.");
690 return false;
691 }
692
693 // allocate from java heap
694 if (!G1CollectedHeap::heap()->alloc_archive_regions(string_ranges, num_ranges)) {
695 fail_continue("Unable to allocate shared string space: range is "
696 "already in use.");
697 return false;
698 }
699
700 // Map the string data. No need to call MemTracker::record_virtual_memory_type()
701 // for mapped string regions as they are part of the reserved java heap, which
702 // is already recorded.
703 for (int i = 0; i < num_ranges; i++) {
704 si = &_header->_space[MetaspaceShared::first_string + i];
705 char* addr = (char*)string_ranges[i].start();
706 char* base = os::map_memory(_fd, _full_path, si->_file_offset,
707 addr, string_ranges[i].byte_size(), si->_read_only,
708 si->_allow_exec);
709 if (base == NULL || base != addr) {
710 fail_continue("Unable to map shared string space at required address.");
711 return false;
712 }
713 }
714
715 if (!verify_string_regions()) {
716 fail_continue("Shared string regions are corrupt");
717 return false;
718 }
719
720 // the shared string data is mapped successfully
721 return true;
722 }
723 } else {
724 if (PrintSharedSpaces && _header->_space[MetaspaceShared::first_string]._used > 0) {
725 tty->print_cr("Shared string data from the CDS archive is being ignored. UseG1GC, "
726 "UseCompressedOops and UseCompressedClassPointers are required.");
727 }
728 }
729
730 // if we get here, the shared string data is not mapped
731 assert(string_ranges == NULL && num_ranges == 0, "sanity");
732 StringTable::ignore_shared_strings(true);
733 #endif
734 return true;
735 }
736
737 bool FileMapInfo::verify_string_regions() {
738 for (int i = MetaspaceShared::first_string;
739 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
740 if (!verify_region_checksum(i)) {
741 return false;
742 }
743 }
744 return true;
745 }
746
747 void FileMapInfo::fixup_string_regions() {
748 // If any string regions were found, call the fill routine to make them parseable.
749 // Note that string_ranges may be non-NULL even if no ranges were found.
750 if (num_ranges != 0) {
751 assert(string_ranges != NULL, "Null string_ranges array with non-zero count");
752 G1CollectedHeap::heap()->fill_archive_regions(string_ranges, num_ranges);
753 }
754 }
755
756 bool FileMapInfo::verify_region_checksum(int i) {
757 if (!VerifySharedSpaces) {
758 return true;
759 }
760
761 size_t sz = _header->_space[i]._used;
762
763 if (sz == 0) {
764 return true; // no data
765 }
766 if (MetaspaceShared::is_string_region(i) && StringTable::shared_string_ignored()) {
767 return true; // shared string data are not mapped
768 }
769 const char* buf = _header->region_addr(i);
770 int crc = ClassLoader::crc32(0, buf, (jint)sz);
771 if (crc != _header->_space[i]._crc) {
772 fail_continue("Checksum verification failed.");
773 return false;
774 }
775 return true;
776 }
777
778 // Unmap a memory region in the address space.
779
780 void FileMapInfo::unmap_region(int i) {
781 assert(!MetaspaceShared::is_string_region(i), "sanity");
782 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
783 size_t used = si->_used;
784 size_t size = align_size_up(used, os::vm_allocation_granularity());
785
786 if (used == 0) {
787 return;
788 }
789
790 char* addr = _header->region_addr(i);
791 if (!os::unmap_memory(addr, size)) {
792 fail_stop("Unable to unmap shared space.");
793 }
794 }
795
796 void FileMapInfo::unmap_string_regions() {
797 for (int i = MetaspaceShared::first_string;
798 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
799 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
800 size_t used = si->_used;
801 if (used > 0) {
802 size_t size = align_size_up(used, os::vm_allocation_granularity());
803 char* addr = (char*)((void*)oopDesc::decode_heap_oop_not_null(
804 (narrowOop)si->_addr._offset));
805 if (!os::unmap_memory(addr, size)) {
806 fail_stop("Unable to unmap shared space.");
807 }
808 }
809 }
810 }
811
812 void FileMapInfo::assert_mark(bool check) {
813 if (!check) {
814 fail_stop("Mark mismatch while restoring from shared file.");
815 }
816 }
817
818
819 FileMapInfo* FileMapInfo::_current_info = NULL;
820 SharedClassPathEntry* FileMapInfo::_classpath_entry_table = NULL;
821 int FileMapInfo::_classpath_entry_table_size = 0;
822 size_t FileMapInfo::_classpath_entry_size = 0x1234baad;
823 bool FileMapInfo::_validating_classpath_entry_table = false;
824
825 // Open the shared archive file, read and validate the header
826 // information (version, boot classpath, etc.). If initialization
827 // fails, shared spaces are disabled and the file is closed. [See
828 // fail_continue.]
829 //
830 // Validation of the archive is done in two steps:
831 //
832 // [1] validate_header() - done here. This checks the header, including _paths_misc_info.
833 // [2] validate_classpath_entry_table - this is done later, because the table is in the RW
834 // region of the archive, which is not mapped yet.
835 bool FileMapInfo::initialize() {
836 assert(UseSharedSpaces, "UseSharedSpaces expected.");
837
838 if (!open_for_read()) {
839 return false;
840 }
841
842 init_from_file(_fd);
843 if (!validate_header()) {
844 return false;
845 }
846
847 SharedReadOnlySize = _header->_space[0]._capacity;
848 SharedReadWriteSize = _header->_space[1]._capacity;
849 SharedMiscDataSize = _header->_space[2]._capacity;
850 SharedMiscCodeSize = _header->_space[3]._capacity;
851 return true;
852 }
853
854 char* FileMapInfo::FileMapHeader::region_addr(int idx) {
855 if (MetaspaceShared::is_string_region(idx)) {
856 return (char*)((void*)oopDesc::decode_heap_oop_not_null(
857 (narrowOop)_space[idx]._addr._offset));
858 } else {
859 return _space[idx]._addr._base;
860 }
861 }
862
863 int FileMapInfo::FileMapHeader::compute_crc() {
864 char* header = data();
865 // start computing from the field after _crc
866 char* buf = (char*)&_crc + sizeof(int);
867 size_t sz = data_size() - (buf - header);
868 int crc = ClassLoader::crc32(0, buf, (jint)sz);
869 return crc;
870 }
871
872 bool FileMapInfo::FileMapHeader::validate() {
873 if (VerifySharedSpaces && compute_crc() != _crc) {
874 fail_continue("Header checksum verification failed.");
875 return false;
876 }
877
878 if (_version != current_version()) {
879 FileMapInfo::fail_continue("The shared archive file is the wrong version.");
880 return false;
881 }
882 if (_magic != (int)0xf00baba2) {
883 FileMapInfo::fail_continue("The shared archive file has a bad magic number.");
884 return false;
885 }
886 char header_version[JVM_IDENT_MAX];
887 get_header_version(header_version);
888 if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) {
889 if (TraceClassPaths) {
890 tty->print_cr("Expected: %s", header_version);
891 tty->print_cr("Actual: %s", _jvm_ident);
892 }
893 FileMapInfo::fail_continue("The shared archive file was created by a different"
894 " version or build of HotSpot");
895 return false;
896 }
897 if (_obj_alignment != ObjectAlignmentInBytes) {
898 FileMapInfo::fail_continue("The shared archive file's ObjectAlignmentInBytes of %d"
899 " does not equal the current ObjectAlignmentInBytes of %d.",
900 _obj_alignment, ObjectAlignmentInBytes);
901 return false;
902 }
903
904 return true;
905 }
906
907 bool FileMapInfo::validate_header() {
908 bool status = _header->validate();
909
910 if (status) {
911 if (!ClassLoader::check_shared_paths_misc_info(_paths_misc_info, _header->_paths_misc_info_size)) {
912 if (!PrintSharedArchiveAndExit) {
913 fail_continue("shared class paths mismatch (hint: enable -XX:+TraceClassPaths to diagnose the failure)");
914 status = false;
915 }
916 }
917 }
918
919 if (_paths_misc_info != NULL) {
920 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
921 _paths_misc_info = NULL;
922 }
923 return status;
924 }
925
926 // The following method is provided to see whether a given pointer
927 // falls in the mapped shared space.
928 // Param:
929 // p, The given pointer
930 // Return:
931 // True if the p is within the mapped shared space, otherwise, false.
932 bool FileMapInfo::is_in_shared_space(const void* p) {
933 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
934 char *base;
935 if (MetaspaceShared::is_string_region(i) && _header->_space[i]._used == 0) {
936 continue;
937 }
938 base = _header->region_addr(i);
939 if (p >= base && p < base + _header->_space[i]._used) {
940 return true;
941 }
942 }
943
944 return false;
945 }
946
947 void FileMapInfo::print_shared_spaces() {
948 gclog_or_tty->print_cr("Shared Spaces:");
949 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
950 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
951 char *base = _header->region_addr(i);
952 gclog_or_tty->print(" %s " INTPTR_FORMAT "-" INTPTR_FORMAT,
953 shared_region_name[i],
954 base, base + si->_used);
955 }
956 }
957
958 // Unmap mapped regions of shared space.
959 void FileMapInfo::stop_sharing_and_unmap(const char* msg) {
960 FileMapInfo *map_info = FileMapInfo::current_info();
961 if (map_info) {
962 map_info->fail_continue("%s", msg);
963 for (int i = 0; i < MetaspaceShared::num_non_strings; i++) {
964 char *addr = map_info->_header->region_addr(i);
965 if (addr != NULL && !MetaspaceShared::is_string_region(i)) {
966 map_info->unmap_region(i);
967 map_info->_header->_space[i]._addr._base = NULL;
968 }
969 }
970 map_info->unmap_string_regions();
971 } else if (DumpSharedSpaces) {
972 fail_stop("%s", msg);
973 }
974 }