1 /*
2 * Copyright (c) 2003, 2016, 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/compactHashtable.inline.hpp"
28 #include "classfile/sharedClassUtil.hpp"
29 #include "classfile/symbolTable.hpp"
30 #include "classfile/systemDictionaryShared.hpp"
31 #include "classfile/altHashing.hpp"
32 #if INCLUDE_ALL_GCS
33 #include "gc/g1/g1CollectedHeap.hpp"
34 #endif
35 #include "memory/filemap.hpp"
36 #include "memory/metadataFactory.hpp"
37 #include "memory/oopFactory.hpp"
38 #include "oops/objArrayOop.hpp"
39 #include "prims/jvmtiExport.hpp"
40 #include "runtime/arguments.hpp"
41 #include "runtime/java.hpp"
42 #include "runtime/os.hpp"
43 #include "runtime/vm_version.hpp"
44 #include "services/memTracker.hpp"
45 #include "utilities/defaultStream.hpp"
46
47 # include <sys/stat.h>
48 # include <errno.h>
49
50 #ifndef O_BINARY // if defined (Win32) use binary files.
51 #define O_BINARY 0 // otherwise do nothing.
52 #endif
53
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 _compact_strings = CompactStrings;
173 _narrow_oop_mode = Universe::narrow_oop_mode();
174 _narrow_oop_shift = Universe::narrow_oop_shift();
175 _max_heap_size = MaxHeapSize;
176 _narrow_klass_base = Universe::narrow_klass_base();
177 _narrow_klass_shift = Universe::narrow_klass_shift();
178 _classpath_entry_table_size = mapinfo->_classpath_entry_table_size;
179 _classpath_entry_table = mapinfo->_classpath_entry_table;
180 _classpath_entry_size = mapinfo->_classpath_entry_size;
181
182 // The following fields are for sanity checks for whether this archive
183 // will function correctly with this JVM and the bootclasspath it's
184 // invoked with.
185
186 // JVM version string ... changes on each build.
187 get_header_version(_jvm_ident);
188 }
189
190 void FileMapInfo::allocate_classpath_entry_table() {
191 int bytes = 0;
192 int count = 0;
193 char* strptr = NULL;
194 char* strptr_max = NULL;
195 Thread* THREAD = Thread::current();
196
197 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
198 size_t entry_size = SharedClassUtil::shared_class_path_entry_size();
199
200 for (int pass=0; pass<2; pass++) {
201 ClassPathEntry *cpe = ClassLoader::classpath_entry(0);
202
203 for (int cur_entry = 0 ; cpe != NULL; cpe = cpe->next(), cur_entry++) {
204 const char *name = cpe->name();
205 int name_bytes = (int)(strlen(name) + 1);
206
207 if (pass == 0) {
208 count ++;
209 bytes += (int)entry_size;
210 bytes += name_bytes;
211 if (TraceClassPaths) {
212 tty->print_cr("[Add main shared path (%s) %s]", (cpe->is_jar_file() ? "jar" : "dir"), name);
213 }
214 if (log_is_enabled(Debug, classload)) {
215 log_debug(classload)("[Add main shared path (%s) %s]", (cpe->is_jar_file() ? "jar" : "dir"), name);
216 }
217 } else {
218 SharedClassPathEntry* ent = shared_classpath(cur_entry);
219 if (cpe->is_jar_file()) {
220 struct stat st;
221 if (os::stat(name, &st) != 0) {
222 // The file/dir must exist, or it would not have been added
223 // into ClassLoader::classpath_entry().
224 //
225 // If we can't access a jar file in the boot path, then we can't
226 // make assumptions about where classes get loaded from.
227 FileMapInfo::fail_stop("Unable to open jar file %s.", name);
228 }
229
230 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error.
231 SharedClassUtil::update_shared_classpath(cpe, ent, st.st_mtime, st.st_size, THREAD);
232 } else {
233 struct stat st;
234 if ((os::stat(name, &st) == 0) && ((st.st_mode & S_IFDIR) == S_IFDIR)) {
235 if (!os::dir_is_empty(name)) {
236 ClassLoader::exit_with_path_failure("Cannot have non-empty directory in archived classpaths", name);
237 }
238 ent->_filesize = -1;
239 } else {
240 ent->_filesize = -2;
241 }
242 }
243 ent->_name = strptr;
244 if (strptr + name_bytes <= strptr_max) {
245 strncpy(strptr, name, (size_t)name_bytes); // name_bytes includes trailing 0.
246 strptr += name_bytes;
247 } else {
248 assert(0, "miscalculated buffer size");
249 }
250 }
251 }
252
253 if (pass == 0) {
254 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error.
255 Array<u8>* arr = MetadataFactory::new_array<u8>(loader_data, (bytes + 7)/8, THREAD);
256 strptr = (char*)(arr->data());
257 strptr_max = strptr + bytes;
258 SharedClassPathEntry* table = (SharedClassPathEntry*)strptr;
259 strptr += entry_size * count;
260
261 _classpath_entry_table_size = count;
262 _classpath_entry_table = table;
263 _classpath_entry_size = entry_size;
264 }
265 }
266 }
267
268 bool FileMapInfo::validate_classpath_entry_table() {
269 _validating_classpath_entry_table = true;
270
271 int count = _header->_classpath_entry_table_size;
272
273 _classpath_entry_table = _header->_classpath_entry_table;
274 _classpath_entry_size = _header->_classpath_entry_size;
275
276 for (int i=0; i<count; i++) {
277 SharedClassPathEntry* ent = shared_classpath(i);
278 struct stat st;
279 const char* name = ent->_name;
280 bool ok = true;
281 if (TraceClassPaths) {
282 tty->print_cr("[Checking shared classpath entry: %s]", name);
283 }
284 if (log_is_enabled(Debug, classload)) {
285 log_debug(classload)("[Checking shared classpath entry: %s]", name);
286 }
287 if (os::stat(name, &st) != 0) {
288 fail_continue("Required classpath entry does not exist: %s", name);
289 ok = false;
290 } else if (ent->is_dir()) {
291 if (!os::dir_is_empty(name)) {
292 fail_continue("directory is not empty: %s", name);
293 ok = false;
294 }
295 } else if (ent->is_jar()) {
296 if (ent->_timestamp != st.st_mtime ||
297 ent->_filesize != st.st_size) {
298 ok = false;
299 if (PrintSharedArchiveAndExit) {
300 fail_continue(ent->_timestamp != st.st_mtime ?
301 "Timestamp mismatch" :
302 "File size mismatch");
303 } else {
304 fail_continue("A jar file is not the one used while building"
305 " the shared archive file: %s", name);
306 }
307 }
308 }
309 if (ok) {
310 if (TraceClassPaths) {
311 tty->print_cr("[ok]");
312 }
313 if (log_is_enabled(Debug, classload)) {
314 log_debug(classload)("[ok]");
315 }
316 } else if (!PrintSharedArchiveAndExit) {
317 _validating_classpath_entry_table = false;
318 return false;
319 }
320 }
321
322 _classpath_entry_table_size = _header->_classpath_entry_table_size;
323 _validating_classpath_entry_table = false;
324 return true;
325 }
326
327
328 // Read the FileMapInfo information from the file.
329
330 bool FileMapInfo::init_from_file(int fd) {
331 size_t sz = _header->data_size();
332 char* addr = _header->data();
333 size_t n = os::read(fd, addr, (unsigned int)sz);
334 if (n != sz) {
335 fail_continue("Unable to read the file header.");
336 return false;
337 }
338 if (_header->_version != current_version()) {
339 fail_continue("The shared archive file has the wrong version.");
340 return false;
341 }
342 _file_offset = (long)n;
343
344 size_t info_size = _header->_paths_misc_info_size;
345 _paths_misc_info = NEW_C_HEAP_ARRAY_RETURN_NULL(char, info_size, mtClass);
346 if (_paths_misc_info == NULL) {
347 fail_continue("Unable to read the file header.");
348 return false;
349 }
350 n = os::read(fd, _paths_misc_info, (unsigned int)info_size);
351 if (n != info_size) {
352 fail_continue("Unable to read the shared path info header.");
353 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
354 _paths_misc_info = NULL;
355 return false;
356 }
357
358 size_t len = lseek(fd, 0, SEEK_END);
359 struct FileMapInfo::FileMapHeader::space_info* si =
360 &_header->_space[MetaspaceShared::mc];
361 if (si->_file_offset >= len || len - si->_file_offset < si->_used) {
362 fail_continue("The shared archive file has been truncated.");
363 return false;
364 }
365
366 _file_offset += (long)n;
367 return true;
368 }
369
370
371 // Read the FileMapInfo information from the file.
372 bool FileMapInfo::open_for_read() {
373 _full_path = Arguments::GetSharedArchivePath();
374 int fd = open(_full_path, O_RDONLY | O_BINARY, 0);
375 if (fd < 0) {
376 if (errno == ENOENT) {
377 // Not locating the shared archive is ok.
378 fail_continue("Specified shared archive not found.");
379 } else {
380 fail_continue("Failed to open shared archive file (%s).",
381 strerror(errno));
382 }
383 return false;
384 }
385
386 _fd = fd;
387 _file_open = true;
388 return true;
389 }
390
391
392 // Write the FileMapInfo information to the file.
393
394 void FileMapInfo::open_for_write() {
395 _full_path = Arguments::GetSharedArchivePath();
396 if (PrintSharedSpaces) {
397 tty->print_cr("Dumping shared data to file: ");
398 tty->print_cr(" %s", _full_path);
399 }
400
401 #ifdef _WINDOWS // On Windows, need WRITE permission to remove the file.
402 chmod(_full_path, _S_IREAD | _S_IWRITE);
403 #endif
404
405 // Use remove() to delete the existing file because, on Unix, this will
406 // allow processes that have it open continued access to the file.
407 remove(_full_path);
408 int fd = open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444);
409 if (fd < 0) {
410 fail_stop("Unable to create shared archive file %s: (%s).", _full_path,
411 strerror(errno));
412 }
413 _fd = fd;
414 _file_offset = 0;
415 _file_open = true;
416 }
417
418
419 // Write the header to the file, seek to the next allocation boundary.
420
421 void FileMapInfo::write_header() {
422 int info_size = ClassLoader::get_shared_paths_misc_info_size();
423
424 _header->_paths_misc_info_size = info_size;
425
426 align_file_position();
427 size_t sz = _header->data_size();
428 char* addr = _header->data();
429 write_bytes(addr, (int)sz); // skip the C++ vtable
430 write_bytes(ClassLoader::get_shared_paths_misc_info(), info_size);
431 align_file_position();
432 }
433
434
435 // Dump shared spaces to file.
436
437 void FileMapInfo::write_space(int i, Metaspace* space, bool read_only) {
438 align_file_position();
439 size_t used = space->used_bytes_slow(Metaspace::NonClassType);
440 size_t capacity = space->capacity_bytes_slow(Metaspace::NonClassType);
441 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
442 write_region(i, (char*)space->bottom(), used, capacity, read_only, false);
443 }
444
445
446 // Dump region to file.
447
448 void FileMapInfo::write_region(int region, char* base, size_t size,
449 size_t capacity, bool read_only,
450 bool allow_exec) {
451 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[region];
452
453 if (_file_open) {
454 guarantee(si->_file_offset == _file_offset, "file offset mismatch.");
455 if (PrintSharedSpaces) {
456 tty->print_cr("Shared file region %d: " SIZE_FORMAT_HEX_W(6) " bytes, addr " INTPTR_FORMAT
457 " file offset " SIZE_FORMAT_HEX_W(6), region, size, p2i(base), _file_offset);
458 }
459 } else {
460 si->_file_offset = _file_offset;
461 }
462 if (MetaspaceShared::is_string_region(region)) {
463 assert((base - (char*)Universe::narrow_oop_base()) % HeapWordSize == 0, "Sanity");
464 if (base != NULL) {
465 si->_addr._offset = (intx)oopDesc::encode_heap_oop_not_null((oop)base);
466 } else {
467 si->_addr._offset = 0;
468 }
469 } else {
470 si->_addr._base = base;
471 }
472 si->_used = size;
473 si->_capacity = capacity;
474 si->_read_only = read_only;
475 si->_allow_exec = allow_exec;
476 si->_crc = ClassLoader::crc32(0, base, (jint)size);
477 write_bytes_aligned(base, (int)size);
478 }
479
480 // Write the string space. The string space contains one or multiple GC(G1) regions.
481 // When the total string space size is smaller than one GC region of the dump time,
482 // only one string region is used for shared strings.
483 //
484 // If the total string space size is bigger than one GC region, there would be more
485 // than one GC regions allocated for shared strings. The first/bottom GC region might
486 // be a partial GC region with the empty portion at the higher address within that region.
487 // The non-empty portion of the first region is written into the archive as one string
488 // region. The rest are consecutive full GC regions if they exist, which can be written
489 // out in one chunk as another string region.
490 void FileMapInfo::write_string_regions(GrowableArray<MemRegion> *regions) {
491 for (int i = MetaspaceShared::first_string;
492 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
493 char* start = NULL;
494 size_t size = 0;
495 if (regions->is_nonempty()) {
496 if (i == MetaspaceShared::first_string) {
497 MemRegion first = regions->first();
498 start = (char*)first.start();
499 size = first.byte_size();
500 } else {
501 int len = regions->length();
502 if (len > 1) {
503 start = (char*)regions->at(1).start();
504 size = (char*)regions->at(len - 1).end() - start;
505 }
506 }
507 }
508 write_region(i, start, size, size, false, false);
509 }
510 }
511
512
513 // Dump bytes to file -- at the current file position.
514
515 void FileMapInfo::write_bytes(const void* buffer, int nbytes) {
516 if (_file_open) {
517 int n = ::write(_fd, buffer, nbytes);
518 if (n != nbytes) {
519 // It is dangerous to leave the corrupted shared archive file around,
520 // close and remove the file. See bug 6372906.
521 close();
522 remove(_full_path);
523 fail_stop("Unable to write to shared archive file.");
524 }
525 }
526 _file_offset += nbytes;
527 }
528
529
530 // Align file position to an allocation unit boundary.
531
532 void FileMapInfo::align_file_position() {
533 size_t new_file_offset = align_size_up(_file_offset,
534 os::vm_allocation_granularity());
535 if (new_file_offset != _file_offset) {
536 _file_offset = new_file_offset;
537 if (_file_open) {
538 // Seek one byte back from the target and write a byte to insure
539 // that the written file is the correct length.
540 _file_offset -= 1;
541 if (lseek(_fd, (long)_file_offset, SEEK_SET) < 0) {
542 fail_stop("Unable to seek.");
543 }
544 char zero = 0;
545 write_bytes(&zero, 1);
546 }
547 }
548 }
549
550
551 // Dump bytes to file -- at the current file position.
552
553 void FileMapInfo::write_bytes_aligned(const void* buffer, int nbytes) {
554 align_file_position();
555 write_bytes(buffer, nbytes);
556 align_file_position();
557 }
558
559
560 // Close the shared archive file. This does NOT unmap mapped regions.
561
562 void FileMapInfo::close() {
563 if (_file_open) {
564 if (::close(_fd) < 0) {
565 fail_stop("Unable to close the shared archive file.");
566 }
567 _file_open = false;
568 _fd = -1;
569 }
570 }
571
572
573 // JVM/TI RedefineClasses() support:
574 // Remap the shared readonly space to shared readwrite, private.
575 bool FileMapInfo::remap_shared_readonly_as_readwrite() {
576 int idx = 0;
577 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[idx];
578 if (!si->_read_only) {
579 // the space is already readwrite so we are done
580 return true;
581 }
582 size_t used = si->_used;
583 size_t size = align_size_up(used, os::vm_allocation_granularity());
584 if (!open_for_read()) {
585 return false;
586 }
587 char *addr = _header->region_addr(idx);
588 char *base = os::remap_memory(_fd, _full_path, si->_file_offset,
589 addr, size, false /* !read_only */,
590 si->_allow_exec);
591 close();
592 if (base == NULL) {
593 fail_continue("Unable to remap shared readonly space (errno=%d).", errno);
594 return false;
595 }
596 if (base != addr) {
597 fail_continue("Unable to remap shared readonly space at required address.");
598 return false;
599 }
600 si->_read_only = false;
601 return true;
602 }
603
604 // Map the whole region at once, assumed to be allocated contiguously.
605 ReservedSpace FileMapInfo::reserve_shared_memory() {
606 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[0];
607 char* requested_addr = _header->region_addr(0);
608
609 size_t size = FileMapInfo::shared_spaces_size();
610
611 // Reserve the space first, then map otherwise map will go right over some
612 // other reserved memory (like the code cache).
613 ReservedSpace rs(size, os::vm_allocation_granularity(), false, requested_addr);
614 if (!rs.is_reserved()) {
615 fail_continue("Unable to reserve shared space at required address "
616 INTPTR_FORMAT, p2i(requested_addr));
617 return rs;
618 }
619 // the reserved virtual memory is for mapping class data sharing archive
620 MemTracker::record_virtual_memory_type((address)rs.base(), mtClassShared);
621
622 return rs;
623 }
624
625 // Memory map a region in the address space.
626 static const char* shared_region_name[] = { "ReadOnly", "ReadWrite", "MiscData", "MiscCode",
627 "String1", "String2" };
628
629 char* FileMapInfo::map_region(int i) {
630 assert(!MetaspaceShared::is_string_region(i), "sanity");
631 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
632 size_t used = si->_used;
633 size_t alignment = os::vm_allocation_granularity();
634 size_t size = align_size_up(used, alignment);
635 char *requested_addr = _header->region_addr(i);
636
637 // If a tool agent is in use (debugging enabled), we must map the address space RW
638 if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space()) {
639 si->_read_only = false;
640 }
641
642 // map the contents of the CDS archive in this memory
643 char *base = os::map_memory(_fd, _full_path, si->_file_offset,
644 requested_addr, size, si->_read_only,
645 si->_allow_exec);
646 if (base == NULL || base != requested_addr) {
647 fail_continue("Unable to map %s shared space at required address.", shared_region_name[i]);
648 return NULL;
649 }
650 #ifdef _WINDOWS
651 // This call is Windows-only because the memory_type gets recorded for the other platforms
652 // in method FileMapInfo::reserve_shared_memory(), which is not called on Windows.
653 MemTracker::record_virtual_memory_type((address)base, mtClassShared);
654 #endif
655
656 return base;
657 }
658
659 static MemRegion *string_ranges = NULL;
660 static int num_ranges = 0;
661 bool FileMapInfo::map_string_regions() {
662 #if INCLUDE_ALL_GCS
663 if (UseG1GC && UseCompressedOops && UseCompressedClassPointers) {
664 // Check that all the narrow oop and klass encodings match the archive
665 if (narrow_oop_mode() != Universe::narrow_oop_mode() ||
666 narrow_oop_shift() != Universe::narrow_oop_shift() ||
667 narrow_klass_base() != Universe::narrow_klass_base() ||
668 narrow_klass_shift() != Universe::narrow_klass_shift()) {
669 if (PrintSharedSpaces && _header->_space[MetaspaceShared::first_string]._used > 0) {
670 tty->print_cr("Shared string data from the CDS archive is being ignored. "
671 "The current CompressedOops/CompressedClassPointers encoding differs from "
672 "that archived due to heap size change. The archive was dumped using max heap "
673 "size " UINTX_FORMAT "M.", max_heap_size()/M);
674 }
675 } else {
676 string_ranges = new MemRegion[MetaspaceShared::max_strings];
677 struct FileMapInfo::FileMapHeader::space_info* si;
678
679 for (int i = MetaspaceShared::first_string;
680 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
681 si = &_header->_space[i];
682 size_t used = si->_used;
683 if (used > 0) {
684 size_t size = used;
685 char* requested_addr = (char*)((void*)oopDesc::decode_heap_oop_not_null(
686 (narrowOop)si->_addr._offset));
687 string_ranges[num_ranges] = MemRegion((HeapWord*)requested_addr, size / HeapWordSize);
688 num_ranges ++;
689 }
690 }
691
692 if (num_ranges == 0) {
693 StringTable::ignore_shared_strings(true);
694 return true; // no shared string data
695 }
696
697 // Check that ranges are within the java heap
698 if (!G1CollectedHeap::heap()->check_archive_addresses(string_ranges, num_ranges)) {
699 fail_continue("Unable to allocate shared string space: range is not "
700 "within java heap.");
701 return false;
702 }
703
704 // allocate from java heap
705 if (!G1CollectedHeap::heap()->alloc_archive_regions(string_ranges, num_ranges)) {
706 fail_continue("Unable to allocate shared string space: range is "
707 "already in use.");
708 return false;
709 }
710
711 // Map the string data. No need to call MemTracker::record_virtual_memory_type()
712 // for mapped string regions as they are part of the reserved java heap, which
713 // is already recorded.
714 for (int i = 0; i < num_ranges; i++) {
715 si = &_header->_space[MetaspaceShared::first_string + i];
716 char* addr = (char*)string_ranges[i].start();
717 char* base = os::map_memory(_fd, _full_path, si->_file_offset,
718 addr, string_ranges[i].byte_size(), si->_read_only,
719 si->_allow_exec);
720 if (base == NULL || base != addr) {
721 // dealloc the string regions from java heap
722 dealloc_string_regions();
723 fail_continue("Unable to map shared string space at required address.");
724 return false;
725 }
726 }
727
728 if (!verify_string_regions()) {
729 // dealloc the string regions from java heap
730 dealloc_string_regions();
731 fail_continue("Shared string regions are corrupt");
732 return false;
733 }
734
735 // the shared string data is mapped successfully
736 return true;
737 }
738 } else {
739 if (PrintSharedSpaces && _header->_space[MetaspaceShared::first_string]._used > 0) {
740 tty->print_cr("Shared string data from the CDS archive is being ignored. UseG1GC, "
741 "UseCompressedOops and UseCompressedClassPointers are required.");
742 }
743 }
744
745 // if we get here, the shared string data is not mapped
746 assert(string_ranges == NULL && num_ranges == 0, "sanity");
747 StringTable::ignore_shared_strings(true);
748 #endif
749 return true;
750 }
751
752 bool FileMapInfo::verify_string_regions() {
753 for (int i = MetaspaceShared::first_string;
754 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
755 if (!verify_region_checksum(i)) {
756 return false;
757 }
758 }
759 return true;
760 }
761
762 void FileMapInfo::fixup_string_regions() {
763 #if INCLUDE_ALL_GCS
764 // If any string regions were found, call the fill routine to make them parseable.
765 // Note that string_ranges may be non-NULL even if no ranges were found.
766 if (num_ranges != 0) {
767 assert(string_ranges != NULL, "Null string_ranges array with non-zero count");
768 G1CollectedHeap::heap()->fill_archive_regions(string_ranges, num_ranges);
769 }
770 #endif
771 }
772
773 bool FileMapInfo::verify_region_checksum(int i) {
774 if (!VerifySharedSpaces) {
775 return true;
776 }
777
778 size_t sz = _header->_space[i]._used;
779
780 if (sz == 0) {
781 return true; // no data
782 }
783 if (MetaspaceShared::is_string_region(i) && StringTable::shared_string_ignored()) {
784 return true; // shared string data are not mapped
785 }
786 const char* buf = _header->region_addr(i);
787 int crc = ClassLoader::crc32(0, buf, (jint)sz);
788 if (crc != _header->_space[i]._crc) {
789 fail_continue("Checksum verification failed.");
790 return false;
791 }
792 return true;
793 }
794
795 // Unmap a memory region in the address space.
796
797 void FileMapInfo::unmap_region(int i) {
798 assert(!MetaspaceShared::is_string_region(i), "sanity");
799 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
800 size_t used = si->_used;
801 size_t size = align_size_up(used, os::vm_allocation_granularity());
802
803 if (used == 0) {
804 return;
805 }
806
807 char* addr = _header->region_addr(i);
808 if (!os::unmap_memory(addr, size)) {
809 fail_stop("Unable to unmap shared space.");
810 }
811 }
812
813 // dealloc the archived string region from java heap
814 void FileMapInfo::dealloc_string_regions() {
815 #if INCLUDE_ALL_GCS
816 if (num_ranges > 0) {
817 assert(string_ranges != NULL, "Null string_ranges array with non-zero count");
818 G1CollectedHeap::heap()->dealloc_archive_regions(string_ranges, num_ranges);
819 }
820 #endif
821 }
822
823 void FileMapInfo::assert_mark(bool check) {
824 if (!check) {
825 fail_stop("Mark mismatch while restoring from shared file.");
826 }
827 }
828
829
830 FileMapInfo* FileMapInfo::_current_info = NULL;
831 SharedClassPathEntry* FileMapInfo::_classpath_entry_table = NULL;
832 int FileMapInfo::_classpath_entry_table_size = 0;
833 size_t FileMapInfo::_classpath_entry_size = 0x1234baad;
834 bool FileMapInfo::_validating_classpath_entry_table = false;
835
836 // Open the shared archive file, read and validate the header
837 // information (version, boot classpath, etc.). If initialization
838 // fails, shared spaces are disabled and the file is closed. [See
839 // fail_continue.]
840 //
841 // Validation of the archive is done in two steps:
842 //
843 // [1] validate_header() - done here. This checks the header, including _paths_misc_info.
844 // [2] validate_classpath_entry_table - this is done later, because the table is in the RW
845 // region of the archive, which is not mapped yet.
846 bool FileMapInfo::initialize() {
847 assert(UseSharedSpaces, "UseSharedSpaces expected.");
848
849 if (!open_for_read()) {
850 return false;
851 }
852
853 init_from_file(_fd);
854 if (!validate_header()) {
855 return false;
856 }
857
858 SharedReadOnlySize = _header->_space[0]._capacity;
859 SharedReadWriteSize = _header->_space[1]._capacity;
860 SharedMiscDataSize = _header->_space[2]._capacity;
861 SharedMiscCodeSize = _header->_space[3]._capacity;
862 return true;
863 }
864
865 char* FileMapInfo::FileMapHeader::region_addr(int idx) {
866 if (MetaspaceShared::is_string_region(idx)) {
867 return (char*)((void*)oopDesc::decode_heap_oop_not_null(
868 (narrowOop)_space[idx]._addr._offset));
869 } else {
870 return _space[idx]._addr._base;
871 }
872 }
873
874 int FileMapInfo::FileMapHeader::compute_crc() {
875 char* header = data();
876 // start computing from the field after _crc
877 char* buf = (char*)&_crc + sizeof(int);
878 size_t sz = data_size() - (buf - header);
879 int crc = ClassLoader::crc32(0, buf, (jint)sz);
880 return crc;
881 }
882
883 bool FileMapInfo::FileMapHeader::validate() {
884 if (VerifySharedSpaces && compute_crc() != _crc) {
885 fail_continue("Header checksum verification failed.");
886 return false;
887 }
888
889 if (_version != current_version()) {
890 FileMapInfo::fail_continue("The shared archive file is the wrong version.");
891 return false;
892 }
893 if (_magic != (int)0xf00baba2) {
894 FileMapInfo::fail_continue("The shared archive file has a bad magic number.");
895 return false;
896 }
897 char header_version[JVM_IDENT_MAX];
898 get_header_version(header_version);
899 if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) {
900 if (TraceClassPaths) {
901 tty->print_cr("Expected: %s", header_version);
902 tty->print_cr("Actual: %s", _jvm_ident);
903 }
904 FileMapInfo::fail_continue("The shared archive file was created by a different"
905 " version or build of HotSpot");
906 return false;
907 }
908 if (_obj_alignment != ObjectAlignmentInBytes) {
909 FileMapInfo::fail_continue("The shared archive file's ObjectAlignmentInBytes of %d"
910 " does not equal the current ObjectAlignmentInBytes of " INTX_FORMAT ".",
911 _obj_alignment, ObjectAlignmentInBytes);
912 return false;
913 }
914 if (_compact_strings != CompactStrings) {
915 FileMapInfo::fail_continue("The shared archive file's CompactStrings setting (%s)"
916 " does not equal the current CompactStrings setting (%s).",
917 _compact_strings ? "enabled" : "disabled",
918 CompactStrings ? "enabled" : "disabled");
919 return false;
920 }
921
922 return true;
923 }
924
925 bool FileMapInfo::validate_header() {
926 bool status = _header->validate();
927
928 if (status) {
929 if (!ClassLoader::check_shared_paths_misc_info(_paths_misc_info, _header->_paths_misc_info_size)) {
930 if (!PrintSharedArchiveAndExit) {
931 fail_continue("shared class paths mismatch (hint: enable -XX:+TraceClassPaths to diagnose the failure)");
932 status = false;
933 }
934 }
935 }
936
937 if (_paths_misc_info != NULL) {
938 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
939 _paths_misc_info = NULL;
940 }
941 return status;
942 }
943
944 // The following method is provided to see whether a given pointer
945 // falls in the mapped shared space.
946 // Param:
947 // p, The given pointer
948 // Return:
949 // True if the p is within the mapped shared space, otherwise, false.
950 bool FileMapInfo::is_in_shared_space(const void* p) {
951 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
952 char *base;
953 if (MetaspaceShared::is_string_region(i) && _header->_space[i]._used == 0) {
954 continue;
955 }
956 base = _header->region_addr(i);
957 if (p >= base && p < base + _header->_space[i]._used) {
958 return true;
959 }
960 }
961
962 return false;
963 }
964
965 void FileMapInfo::print_shared_spaces() {
966 tty->print_cr("Shared Spaces:");
967 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
968 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
969 char *base = _header->region_addr(i);
970 tty->print(" %s " INTPTR_FORMAT "-" INTPTR_FORMAT,
971 shared_region_name[i],
972 p2i(base), p2i(base + si->_used));
973 }
974 }
975
976 // Unmap mapped regions of shared space.
977 void FileMapInfo::stop_sharing_and_unmap(const char* msg) {
978 FileMapInfo *map_info = FileMapInfo::current_info();
979 if (map_info) {
980 map_info->fail_continue("%s", msg);
981 for (int i = 0; i < MetaspaceShared::num_non_strings; i++) {
982 char *addr = map_info->_header->region_addr(i);
983 if (addr != NULL && !MetaspaceShared::is_string_region(i)) {
984 map_info->unmap_region(i);
985 map_info->_header->_space[i]._addr._base = NULL;
986 }
987 }
988 // Dealloc the string regions only without unmapping. The string regions are part
989 // of the java heap. Unmapping of the heap regions are managed by GC.
990 map_info->dealloc_string_regions();
991 } else if (DumpSharedSpaces) {
992 fail_stop("%s", msg);
993 }
994 }