1 /*
2 * Copyright (c) 2003, 2017, 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 "logging/log.hpp"
36 #include "logging/logStream.hpp"
37 #include "logging/logMessage.hpp"
38 #include "memory/filemap.hpp"
39 #include "memory/metadataFactory.hpp"
40 #include "memory/oopFactory.hpp"
41 #include "oops/objArrayOop.hpp"
42 #include "prims/jvm.h"
43 #include "prims/jvmtiExport.hpp"
44 #include "runtime/arguments.hpp"
45 #include "runtime/java.hpp"
46 #include "runtime/os.hpp"
47 #include "runtime/vm_version.hpp"
48 #include "services/memTracker.hpp"
49 #include "utilities/align.hpp"
50 #include "utilities/defaultStream.hpp"
51
52 # include <sys/stat.h>
53 # include <errno.h>
54
55 #ifndef O_BINARY // if defined (Win32) use binary files.
56 #define O_BINARY 0 // otherwise do nothing.
57 #endif
58
59 extern address JVM_FunctionAtStart();
60 extern address JVM_FunctionAtEnd();
61
62 // Complain and stop. All error conditions occurring during the writing of
63 // an archive file should stop the process. Unrecoverable errors during
64 // the reading of the archive file should stop the process.
65
66 static void fail(const char *msg, va_list ap) {
67 // This occurs very early during initialization: tty is not initialized.
68 jio_fprintf(defaultStream::error_stream(),
69 "An error has occurred while processing the"
70 " shared archive file.\n");
71 jio_vfprintf(defaultStream::error_stream(), msg, ap);
72 jio_fprintf(defaultStream::error_stream(), "\n");
73 // Do not change the text of the below message because some tests check for it.
74 vm_exit_during_initialization("Unable to use shared archive.", NULL);
75 }
76
77
78 void FileMapInfo::fail_stop(const char *msg, ...) {
79 va_list ap;
80 va_start(ap, msg);
81 fail(msg, ap); // Never returns.
82 va_end(ap); // for completeness.
83 }
84
85
86 // Complain and continue. Recoverable errors during the reading of the
87 // archive file may continue (with sharing disabled).
88 //
89 // If we continue, then disable shared spaces and close the file.
90
91 void FileMapInfo::fail_continue(const char *msg, ...) {
92 va_list ap;
93 va_start(ap, msg);
94 MetaspaceShared::set_archive_loading_failed();
95 if (PrintSharedArchiveAndExit && _validating_classpath_entry_table) {
96 // If we are doing PrintSharedArchiveAndExit and some of the classpath entries
97 // do not validate, we can still continue "limping" to validate the remaining
98 // entries. No need to quit.
99 tty->print("[");
100 tty->vprint(msg, ap);
101 tty->print_cr("]");
102 } else {
103 if (RequireSharedSpaces) {
104 fail(msg, ap);
105 } else {
106 if (log_is_enabled(Info, cds)) {
107 ResourceMark rm;
108 LogStream ls(Log(cds)::info());
109 ls.print("UseSharedSpaces: ");
110 ls.vprint_cr(msg, ap);
111 }
112 }
113 UseSharedSpaces = false;
114 assert(current_info() != NULL, "singleton must be registered");
115 current_info()->close();
116 }
117 va_end(ap);
118 }
119
120 // Fill in the fileMapInfo structure with data about this VM instance.
121
122 // This method copies the vm version info into header_version. If the version is too
123 // long then a truncated version, which has a hash code appended to it, is copied.
124 //
125 // Using a template enables this method to verify that header_version is an array of
126 // length JVM_IDENT_MAX. This ensures that the code that writes to the CDS file and
127 // the code that reads the CDS file will both use the same size buffer. Hence, will
128 // use identical truncation. This is necessary for matching of truncated versions.
129 template <int N> static void get_header_version(char (&header_version) [N]) {
130 assert(N == JVM_IDENT_MAX, "Bad header_version size");
131
132 const char *vm_version = VM_Version::internal_vm_info_string();
133 const int version_len = (int)strlen(vm_version);
134
135 if (version_len < (JVM_IDENT_MAX-1)) {
136 strcpy(header_version, vm_version);
137
138 } else {
139 // Get the hash value. Use a static seed because the hash needs to return the same
140 // value over multiple jvm invocations.
141 unsigned int hash = AltHashing::murmur3_32(8191, (const jbyte*)vm_version, version_len);
142
143 // Truncate the ident, saving room for the 8 hex character hash value.
144 strncpy(header_version, vm_version, JVM_IDENT_MAX-9);
145
146 // Append the hash code as eight hex digits.
147 sprintf(&header_version[JVM_IDENT_MAX-9], "%08x", hash);
148 header_version[JVM_IDENT_MAX-1] = 0; // Null terminate.
149 }
150 }
151
152 FileMapInfo::FileMapInfo() {
153 assert(_current_info == NULL, "must be singleton"); // not thread safe
154 _current_info = this;
155 memset((void*)this, 0, sizeof(FileMapInfo));
156 _file_offset = 0;
157 _file_open = false;
158 _header = SharedClassUtil::allocate_file_map_header();
159 _header->_version = _invalid_version;
160 }
161
162 FileMapInfo::~FileMapInfo() {
163 assert(_current_info == this, "must be singleton"); // not thread safe
164 _current_info = NULL;
165 }
166
167 void FileMapInfo::populate_header(size_t alignment) {
168 _header->populate(this, alignment);
169 }
170
171 size_t FileMapInfo::FileMapHeader::data_size() {
172 return SharedClassUtil::file_map_header_size() - sizeof(FileMapInfo::FileMapHeaderBase);
173 }
174
175 void FileMapInfo::FileMapHeader::populate(FileMapInfo* mapinfo, size_t alignment) {
176 _magic = 0xf00baba2;
177 _version = _current_version;
178 _alignment = alignment;
179 _obj_alignment = ObjectAlignmentInBytes;
180 _compact_strings = CompactStrings;
181 _narrow_oop_mode = Universe::narrow_oop_mode();
182 _narrow_oop_shift = Universe::narrow_oop_shift();
183 _max_heap_size = MaxHeapSize;
184 _narrow_klass_base = Universe::narrow_klass_base();
185 _narrow_klass_shift = Universe::narrow_klass_shift();
186 _classpath_entry_table_size = mapinfo->_classpath_entry_table_size;
187 _classpath_entry_table = mapinfo->_classpath_entry_table;
188 _classpath_entry_size = mapinfo->_classpath_entry_size;
189
190 // The following fields are for sanity checks for whether this archive
191 // will function correctly with this JVM and the bootclasspath it's
192 // invoked with.
193
194 // JVM version string ... changes on each build.
195 get_header_version(_jvm_ident);
196 }
197
198 void FileMapInfo::allocate_classpath_entry_table() {
199 int bytes = 0;
200 int count = 0;
201 char* strptr = NULL;
202 char* strptr_max = NULL;
203 Thread* THREAD = Thread::current();
204
205 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
206 size_t entry_size = SharedClassUtil::shared_class_path_entry_size();
207
208 for (int pass=0; pass<2; pass++) {
209
210 // Process the modular java runtime image first
211 ClassPathEntry* jrt_entry = ClassLoader::get_jrt_entry();
212 assert(jrt_entry != NULL,
213 "No modular java runtime image present when allocating the CDS classpath entry table");
214 const char *name = jrt_entry->name();
215 int name_bytes = (int)(strlen(name) + 1);
216 if (pass == 0) {
217 count++;
218 bytes += (int)entry_size;
219 bytes += name_bytes;
220 log_info(class, path)("add main shared path for modular java runtime image %s", name);
221 } else {
222 // The java runtime image is always in slot 0 on the shared class path.
223 SharedClassPathEntry* ent = shared_classpath(0);
224 struct stat st;
225 if (os::stat(name, &st) == 0) {
226 ent->_timestamp = st.st_mtime;
227 ent->_filesize = st.st_size;
228 }
229 if (ent->_filesize == 0) {
230 // unknown
231 ent->_filesize = -2;
232 }
233 ent->_name = strptr;
234 assert(strptr + name_bytes <= strptr_max, "miscalculated buffer size");
235 strncpy(strptr, name, (size_t)name_bytes); // name_bytes includes trailing 0.
236 strptr += name_bytes;
237 }
238
239 // Walk the appended entries, which includes the entries added for the classpath.
240 ClassPathEntry *cpe = ClassLoader::classpath_entry(1);
241
242 // Since the java runtime image is always in slot 0 on the shared class path, the
243 // appended entries are started at slot 1 immediately after.
244 for (int cur_entry = 1 ; cpe != NULL; cpe = cpe->next(), cur_entry++) {
245 const char *name = cpe->name();
246 int name_bytes = (int)(strlen(name) + 1);
247 assert(!cpe->is_jrt(), "A modular java runtime image is present on the list of appended entries");
248
249 if (pass == 0) {
250 count ++;
251 bytes += (int)entry_size;
252 bytes += name_bytes;
253 log_info(class, path)("add main shared path (%s) %s", (cpe->is_jar_file() ? "jar" : "dir"), name);
254 } else {
255 SharedClassPathEntry* ent = shared_classpath(cur_entry);
256 if (cpe->is_jar_file()) {
257 struct stat st;
258 if (os::stat(name, &st) != 0) {
259 // The file/dir must exist, or it would not have been added
260 // into ClassLoader::classpath_entry().
261 //
262 // If we can't access a jar file in the boot path, then we can't
263 // make assumptions about where classes get loaded from.
264 FileMapInfo::fail_stop("Unable to open jar file %s.", name);
265 }
266
267 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error.
268 SharedClassUtil::update_shared_classpath(cpe, ent, st.st_mtime, st.st_size, THREAD);
269 } else {
270 struct stat st;
271 if (os::stat(name, &st) == 0) {
272 if ((st.st_mode & S_IFMT) == S_IFDIR) {
273 if (!os::dir_is_empty(name)) {
274 ClassLoader::exit_with_path_failure(
275 "Cannot have non-empty directory in archived classpaths", name);
276 }
277 ent->_filesize = -1;
278 }
279 }
280 if (ent->_filesize == 0) {
281 // unknown
282 ent->_filesize = -2;
283 }
284 }
285 ent->_name = strptr;
286 if (strptr + name_bytes <= strptr_max) {
287 strncpy(strptr, name, (size_t)name_bytes); // name_bytes includes trailing 0.
288 strptr += name_bytes;
289 } else {
290 assert(0, "miscalculated buffer size");
291 }
292 }
293 }
294
295 if (pass == 0) {
296 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error.
297 Array<u8>* arr = MetadataFactory::new_array<u8>(loader_data, (bytes + 7)/8, THREAD);
298 strptr = (char*)(arr->data());
299 strptr_max = strptr + bytes;
300 SharedClassPathEntry* table = (SharedClassPathEntry*)strptr;
301 strptr += entry_size * count;
302
303 _classpath_entry_table_size = count;
304 _classpath_entry_table = table;
305 _classpath_entry_size = entry_size;
306 }
307 }
308 }
309
310 bool FileMapInfo::validate_classpath_entry_table() {
311 _validating_classpath_entry_table = true;
312
313 int count = _header->_classpath_entry_table_size;
314
315 _classpath_entry_table = _header->_classpath_entry_table;
316 _classpath_entry_size = _header->_classpath_entry_size;
317
318 for (int i=0; i<count; i++) {
319 SharedClassPathEntry* ent = shared_classpath(i);
320 struct stat st;
321 const char* name = ent->_name;
322 bool ok = true;
323 log_info(class, path)("checking shared classpath entry: %s", name);
324 if (os::stat(name, &st) != 0) {
325 fail_continue("Required classpath entry does not exist: %s", name);
326 ok = false;
327 } else if (ent->is_dir()) {
328 if (!os::dir_is_empty(name)) {
329 fail_continue("directory is not empty: %s", name);
330 ok = false;
331 }
332 } else if (ent->is_jar_or_bootimage()) {
333 if (ent->_timestamp != st.st_mtime ||
334 ent->_filesize != st.st_size) {
335 ok = false;
336 if (PrintSharedArchiveAndExit) {
337 fail_continue(ent->_timestamp != st.st_mtime ?
338 "Timestamp mismatch" :
339 "File size mismatch");
340 } else {
341 fail_continue("A jar/jimage file is not the one used while building"
342 " the shared archive file: %s", name);
343 }
344 }
345 }
346 if (ok) {
347 log_info(class, path)("ok");
348 } else if (!PrintSharedArchiveAndExit) {
349 _validating_classpath_entry_table = false;
350 return false;
351 }
352 }
353
354 _classpath_entry_table_size = _header->_classpath_entry_table_size;
355 _validating_classpath_entry_table = false;
356 return true;
357 }
358
359
360 // Read the FileMapInfo information from the file.
361
362 bool FileMapInfo::init_from_file(int fd) {
363 size_t sz = _header->data_size();
364 char* addr = _header->data();
365 size_t n = os::read(fd, addr, (unsigned int)sz);
366 if (n != sz) {
367 fail_continue("Unable to read the file header.");
368 return false;
369 }
370 if (_header->_version != current_version()) {
371 fail_continue("The shared archive file has the wrong version.");
372 return false;
373 }
374 _file_offset = (long)n;
375
376 size_t info_size = _header->_paths_misc_info_size;
377 _paths_misc_info = NEW_C_HEAP_ARRAY_RETURN_NULL(char, info_size, mtClass);
378 if (_paths_misc_info == NULL) {
379 fail_continue("Unable to read the file header.");
380 return false;
381 }
382 n = os::read(fd, _paths_misc_info, (unsigned int)info_size);
383 if (n != info_size) {
384 fail_continue("Unable to read the shared path info header.");
385 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
386 _paths_misc_info = NULL;
387 return false;
388 }
389
390 size_t len = lseek(fd, 0, SEEK_END);
391 struct FileMapInfo::FileMapHeader::space_info* si =
392 &_header->_space[MetaspaceShared::mc];
393 if (si->_file_offset >= len || len - si->_file_offset < si->_used) {
394 fail_continue("The shared archive file has been truncated.");
395 return false;
396 }
397
398 _file_offset += (long)n;
399 return true;
400 }
401
402
403 // Read the FileMapInfo information from the file.
404 bool FileMapInfo::open_for_read() {
405 _full_path = Arguments::GetSharedArchivePath();
406 int fd = open(_full_path, O_RDONLY | O_BINARY, 0);
407 if (fd < 0) {
408 if (errno == ENOENT) {
409 // Not locating the shared archive is ok.
410 fail_continue("Specified shared archive not found.");
411 } else {
412 fail_continue("Failed to open shared archive file (%s).",
413 os::strerror(errno));
414 }
415 return false;
416 }
417
418 _fd = fd;
419 _file_open = true;
420 return true;
421 }
422
423
424 // Write the FileMapInfo information to the file.
425
426 void FileMapInfo::open_for_write() {
427 _full_path = Arguments::GetSharedArchivePath();
428 if (log_is_enabled(Info, cds)) {
429 ResourceMark rm;
430 LogMessage(cds) msg;
431 stringStream info_stream;
432 info_stream.print_cr("Dumping shared data to file: ");
433 info_stream.print_cr(" %s", _full_path);
434 msg.info("%s", info_stream.as_string());
435 }
436
437 #ifdef _WINDOWS // On Windows, need WRITE permission to remove the file.
438 chmod(_full_path, _S_IREAD | _S_IWRITE);
439 #endif
440
441 // Use remove() to delete the existing file because, on Unix, this will
442 // allow processes that have it open continued access to the file.
443 remove(_full_path);
444 int fd = open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444);
445 if (fd < 0) {
446 fail_stop("Unable to create shared archive file %s: (%s).", _full_path,
447 os::strerror(errno));
448 }
449 _fd = fd;
450 _file_offset = 0;
451 _file_open = true;
452 }
453
454
455 // Write the header to the file, seek to the next allocation boundary.
456
457 void FileMapInfo::write_header() {
458 int info_size = ClassLoader::get_shared_paths_misc_info_size();
459
460 _header->_paths_misc_info_size = info_size;
461
462 align_file_position();
463 size_t sz = _header->data_size();
464 char* addr = _header->data();
465 write_bytes(addr, (int)sz); // skip the C++ vtable
466 write_bytes(ClassLoader::get_shared_paths_misc_info(), info_size);
467 align_file_position();
468 }
469
470
471 // Dump shared spaces to file.
472
473 void FileMapInfo::write_space(int i, Metaspace* space, bool read_only) {
474 align_file_position();
475 size_t used = space->used_bytes_slow(Metaspace::NonClassType);
476 size_t capacity = space->capacity_bytes_slow(Metaspace::NonClassType);
477 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
478 write_region(i, (char*)space->bottom(), used, capacity, read_only, false);
479 }
480
481
482 // Dump region to file.
483
484 void FileMapInfo::write_region(int region, char* base, size_t size,
485 size_t capacity, bool read_only,
486 bool allow_exec) {
487 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[region];
488
489 if (_file_open) {
490 guarantee(si->_file_offset == _file_offset, "file offset mismatch.");
491 log_info(cds)("Shared file region %d: " SIZE_FORMAT_HEX_W(6)
492 " bytes, addr " INTPTR_FORMAT " file offset " SIZE_FORMAT_HEX_W(6),
493 region, size, p2i(base), _file_offset);
494 } else {
495 si->_file_offset = _file_offset;
496 }
497 if (MetaspaceShared::is_string_region(region)) {
498 assert((base - (char*)Universe::narrow_oop_base()) % HeapWordSize == 0, "Sanity");
499 if (base != NULL) {
500 si->_addr._offset = (intx)oopDesc::encode_heap_oop_not_null((oop)base);
501 } else {
502 si->_addr._offset = 0;
503 }
504 } else {
505 si->_addr._base = base;
506 }
507 si->_used = size;
508 si->_capacity = capacity;
509 si->_read_only = read_only;
510 si->_allow_exec = allow_exec;
511 si->_crc = ClassLoader::crc32(0, base, (jint)size);
512 write_bytes_aligned(base, (int)size);
513 }
514
515 // Write the string space. The string space contains one or multiple GC(G1) regions.
516 // When the total string space size is smaller than one GC region of the dump time,
517 // only one string region is used for shared strings.
518 //
519 // If the total string space size is bigger than one GC region, there would be more
520 // than one GC regions allocated for shared strings. The first/bottom GC region might
521 // be a partial GC region with the empty portion at the higher address within that region.
522 // The non-empty portion of the first region is written into the archive as one string
523 // region. The rest are consecutive full GC regions if they exist, which can be written
524 // out in one chunk as another string region.
525 void FileMapInfo::write_string_regions(GrowableArray<MemRegion> *regions) {
526 for (int i = MetaspaceShared::first_string;
527 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
528 char* start = NULL;
529 size_t size = 0;
530 if (regions->is_nonempty()) {
531 if (i == MetaspaceShared::first_string) {
532 MemRegion first = regions->first();
533 start = (char*)first.start();
534 size = first.byte_size();
535 } else {
536 int len = regions->length();
537 if (len > 1) {
538 start = (char*)regions->at(1).start();
539 size = (char*)regions->at(len - 1).end() - start;
540 }
541 }
542 }
543 write_region(i, start, size, size, false, false);
544 }
545 }
546
547
548 // Dump bytes to file -- at the current file position.
549
550 void FileMapInfo::write_bytes(const void* buffer, int nbytes) {
551 if (_file_open) {
552 int n = ::write(_fd, buffer, nbytes);
553 if (n != nbytes) {
554 // It is dangerous to leave the corrupted shared archive file around,
555 // close and remove the file. See bug 6372906.
556 close();
557 remove(_full_path);
558 fail_stop("Unable to write to shared archive file.");
559 }
560 }
561 _file_offset += nbytes;
562 }
563
564
565 // Align file position to an allocation unit boundary.
566
567 void FileMapInfo::align_file_position() {
568 size_t new_file_offset = align_up(_file_offset,
569 os::vm_allocation_granularity());
570 if (new_file_offset != _file_offset) {
571 _file_offset = new_file_offset;
572 if (_file_open) {
573 // Seek one byte back from the target and write a byte to insure
574 // that the written file is the correct length.
575 _file_offset -= 1;
576 if (lseek(_fd, (long)_file_offset, SEEK_SET) < 0) {
577 fail_stop("Unable to seek.");
578 }
579 char zero = 0;
580 write_bytes(&zero, 1);
581 }
582 }
583 }
584
585
586 // Dump bytes to file -- at the current file position.
587
588 void FileMapInfo::write_bytes_aligned(const void* buffer, int nbytes) {
589 align_file_position();
590 write_bytes(buffer, nbytes);
591 align_file_position();
592 }
593
594
595 // Close the shared archive file. This does NOT unmap mapped regions.
596
597 void FileMapInfo::close() {
598 if (_file_open) {
599 if (::close(_fd) < 0) {
600 fail_stop("Unable to close the shared archive file.");
601 }
602 _file_open = false;
603 _fd = -1;
604 }
605 }
606
607
608 // JVM/TI RedefineClasses() support:
609 // Remap the shared readonly space to shared readwrite, private.
610 bool FileMapInfo::remap_shared_readonly_as_readwrite() {
611 int idx = 0;
612 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[idx];
613 if (!si->_read_only) {
614 // the space is already readwrite so we are done
615 return true;
616 }
617 size_t used = si->_used;
618 size_t size = align_up(used, os::vm_allocation_granularity());
619 if (!open_for_read()) {
620 return false;
621 }
622 char *addr = _header->region_addr(idx);
623 char *base = os::remap_memory(_fd, _full_path, si->_file_offset,
624 addr, size, false /* !read_only */,
625 si->_allow_exec);
626 close();
627 if (base == NULL) {
628 fail_continue("Unable to remap shared readonly space (errno=%d).", errno);
629 return false;
630 }
631 if (base != addr) {
632 fail_continue("Unable to remap shared readonly space at required address.");
633 return false;
634 }
635 si->_read_only = false;
636 return true;
637 }
638
639 // Map the whole region at once, assumed to be allocated contiguously.
640 ReservedSpace FileMapInfo::reserve_shared_memory() {
641 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[0];
642 char* requested_addr = _header->region_addr(0);
643
644 size_t size = FileMapInfo::shared_spaces_size();
645
646 // Reserve the space first, then map otherwise map will go right over some
647 // other reserved memory (like the code cache).
648 ReservedSpace rs(size, os::vm_allocation_granularity(), false, requested_addr);
649 if (!rs.is_reserved()) {
650 fail_continue("Unable to reserve shared space at required address "
651 INTPTR_FORMAT, p2i(requested_addr));
652 return rs;
653 }
654 // the reserved virtual memory is for mapping class data sharing archive
655 MemTracker::record_virtual_memory_type((address)rs.base(), mtClassShared);
656
657 return rs;
658 }
659
660 // Memory map a region in the address space.
661 static const char* shared_region_name[] = { "ReadOnly", "ReadWrite", "MiscData", "MiscCode",
662 "String1", "String2", "OptionalData" };
663
664 char* FileMapInfo::map_region(int i) {
665 assert(!MetaspaceShared::is_string_region(i), "sanity");
666 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
667 size_t used = si->_used;
668 size_t alignment = os::vm_allocation_granularity();
669 size_t size = align_up(used, alignment);
670 char *requested_addr = _header->region_addr(i);
671
672 // If a tool agent is in use (debugging enabled), we must map the address space RW
673 if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space()) {
674 si->_read_only = false;
675 }
676
677 // map the contents of the CDS archive in this memory
678 char *base = os::map_memory(_fd, _full_path, si->_file_offset,
679 requested_addr, size, si->_read_only,
680 si->_allow_exec);
681 if (base == NULL || base != requested_addr) {
682 fail_continue("Unable to map %s shared space at required address.", shared_region_name[i]);
683 return NULL;
684 }
685 #ifdef _WINDOWS
686 // This call is Windows-only because the memory_type gets recorded for the other platforms
687 // in method FileMapInfo::reserve_shared_memory(), which is not called on Windows.
688 MemTracker::record_virtual_memory_type((address)base, mtClassShared);
689 #endif
690
691 return base;
692 }
693
694 static MemRegion *string_ranges = NULL;
695 static int num_ranges = 0;
696 bool FileMapInfo::map_string_regions() {
697 #if INCLUDE_ALL_GCS
698 if (UseG1GC && UseCompressedOops && UseCompressedClassPointers) {
699 // Check that all the narrow oop and klass encodings match the archive
700 if (narrow_oop_mode() != Universe::narrow_oop_mode() ||
701 narrow_oop_shift() != Universe::narrow_oop_shift() ||
702 narrow_klass_base() != Universe::narrow_klass_base() ||
703 narrow_klass_shift() != Universe::narrow_klass_shift()) {
704 if (log_is_enabled(Info, cds) && _header->_space[MetaspaceShared::first_string]._used > 0) {
705 log_info(cds)("Shared string data from the CDS archive is being ignored. "
706 "The current CompressedOops/CompressedClassPointers encoding differs from "
707 "that archived due to heap size change. The archive was dumped using max heap "
708 "size " UINTX_FORMAT "M.", max_heap_size()/M);
709 }
710 } else {
711 string_ranges = new MemRegion[MetaspaceShared::max_strings];
712 struct FileMapInfo::FileMapHeader::space_info* si;
713
714 for (int i = MetaspaceShared::first_string;
715 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
716 si = &_header->_space[i];
717 size_t used = si->_used;
718 if (used > 0) {
719 size_t size = used;
720 char* requested_addr = (char*)((void*)oopDesc::decode_heap_oop_not_null(
721 (narrowOop)si->_addr._offset));
722 string_ranges[num_ranges] = MemRegion((HeapWord*)requested_addr, size / HeapWordSize);
723 num_ranges ++;
724 }
725 }
726
727 if (num_ranges == 0) {
728 StringTable::ignore_shared_strings(true);
729 return true; // no shared string data
730 }
731
732 // Check that ranges are within the java heap
733 if (!G1CollectedHeap::heap()->check_archive_addresses(string_ranges, num_ranges)) {
734 fail_continue("Unable to allocate shared string space: range is not "
735 "within java heap.");
736 return false;
737 }
738
739 // allocate from java heap
740 if (!G1CollectedHeap::heap()->alloc_archive_regions(string_ranges, num_ranges)) {
741 fail_continue("Unable to allocate shared string space: range is "
742 "already in use.");
743 return false;
744 }
745
746 // Map the string data. No need to call MemTracker::record_virtual_memory_type()
747 // for mapped string regions as they are part of the reserved java heap, which
748 // is already recorded.
749 for (int i = 0; i < num_ranges; i++) {
750 si = &_header->_space[MetaspaceShared::first_string + i];
751 char* addr = (char*)string_ranges[i].start();
752 char* base = os::map_memory(_fd, _full_path, si->_file_offset,
753 addr, string_ranges[i].byte_size(), si->_read_only,
754 si->_allow_exec);
755 if (base == NULL || base != addr) {
756 // dealloc the string regions from java heap
757 dealloc_string_regions();
758 fail_continue("Unable to map shared string space at required address.");
759 return false;
760 }
761 }
762
763 if (!verify_string_regions()) {
764 // dealloc the string regions from java heap
765 dealloc_string_regions();
766 fail_continue("Shared string regions are corrupt");
767 return false;
768 }
769
770 // the shared string data is mapped successfully
771 return true;
772 }
773 } else {
774 if (log_is_enabled(Info, cds) && _header->_space[MetaspaceShared::first_string]._used > 0) {
775 log_info(cds)("Shared string data from the CDS archive is being ignored. UseG1GC, "
776 "UseCompressedOops and UseCompressedClassPointers are required.");
777 }
778 }
779
780 // if we get here, the shared string data is not mapped
781 assert(string_ranges == NULL && num_ranges == 0, "sanity");
782 StringTable::ignore_shared_strings(true);
783 #endif
784 return true;
785 }
786
787 bool FileMapInfo::verify_string_regions() {
788 for (int i = MetaspaceShared::first_string;
789 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
790 if (!verify_region_checksum(i)) {
791 return false;
792 }
793 }
794 return true;
795 }
796
797 void FileMapInfo::fixup_string_regions() {
798 #if INCLUDE_ALL_GCS
799 // If any string regions were found, call the fill routine to make them parseable.
800 // Note that string_ranges may be non-NULL even if no ranges were found.
801 if (num_ranges != 0) {
802 assert(string_ranges != NULL, "Null string_ranges array with non-zero count");
803 G1CollectedHeap::heap()->fill_archive_regions(string_ranges, num_ranges);
804 }
805 #endif
806 }
807
808 bool FileMapInfo::verify_region_checksum(int i) {
809 if (!VerifySharedSpaces) {
810 return true;
811 }
812
813 size_t sz = _header->_space[i]._used;
814
815 if (sz == 0) {
816 return true; // no data
817 }
818 if (MetaspaceShared::is_string_region(i) && StringTable::shared_string_ignored()) {
819 return true; // shared string data are not mapped
820 }
821 const char* buf = _header->region_addr(i);
822 int crc = ClassLoader::crc32(0, buf, (jint)sz);
823 if (crc != _header->_space[i]._crc) {
824 fail_continue("Checksum verification failed.");
825 return false;
826 }
827 return true;
828 }
829
830 // Unmap a memory region in the address space.
831
832 void FileMapInfo::unmap_region(int i) {
833 assert(!MetaspaceShared::is_string_region(i), "sanity");
834 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
835 size_t used = si->_used;
836 size_t size = align_up(used, os::vm_allocation_granularity());
837
838 if (used == 0) {
839 return;
840 }
841
842 char* addr = _header->region_addr(i);
843 if (!os::unmap_memory(addr, size)) {
844 fail_stop("Unable to unmap shared space.");
845 }
846 }
847
848 // dealloc the archived string region from java heap
849 void FileMapInfo::dealloc_string_regions() {
850 #if INCLUDE_ALL_GCS
851 if (num_ranges > 0) {
852 assert(string_ranges != NULL, "Null string_ranges array with non-zero count");
853 G1CollectedHeap::heap()->dealloc_archive_regions(string_ranges, num_ranges);
854 }
855 #endif
856 }
857
858 void FileMapInfo::assert_mark(bool check) {
859 if (!check) {
860 fail_stop("Mark mismatch while restoring from shared file.");
861 }
862 }
863
864
865 FileMapInfo* FileMapInfo::_current_info = NULL;
866 SharedClassPathEntry* FileMapInfo::_classpath_entry_table = NULL;
867 int FileMapInfo::_classpath_entry_table_size = 0;
868 size_t FileMapInfo::_classpath_entry_size = 0x1234baad;
869 bool FileMapInfo::_validating_classpath_entry_table = false;
870
871 // Open the shared archive file, read and validate the header
872 // information (version, boot classpath, etc.). If initialization
873 // fails, shared spaces are disabled and the file is closed. [See
874 // fail_continue.]
875 //
876 // Validation of the archive is done in two steps:
877 //
878 // [1] validate_header() - done here. This checks the header, including _paths_misc_info.
879 // [2] validate_classpath_entry_table - this is done later, because the table is in the RW
880 // region of the archive, which is not mapped yet.
881 bool FileMapInfo::initialize() {
882 assert(UseSharedSpaces, "UseSharedSpaces expected.");
883
884 if (!open_for_read()) {
885 return false;
886 }
887
888 init_from_file(_fd);
889 if (!validate_header()) {
890 return false;
891 }
892
893 SharedReadOnlySize = _header->_space[0]._capacity;
894 SharedReadWriteSize = _header->_space[1]._capacity;
895 SharedMiscDataSize = _header->_space[2]._capacity;
896 SharedMiscCodeSize = _header->_space[3]._capacity;
897 return true;
898 }
899
900 char* FileMapInfo::FileMapHeader::region_addr(int idx) {
901 if (MetaspaceShared::is_string_region(idx)) {
902 return (char*)((void*)oopDesc::decode_heap_oop_not_null(
903 (narrowOop)_space[idx]._addr._offset));
904 } else {
905 return _space[idx]._addr._base;
906 }
907 }
908
909 int FileMapInfo::FileMapHeader::compute_crc() {
910 char* header = data();
911 // start computing from the field after _crc
912 char* buf = (char*)&_crc + sizeof(int);
913 size_t sz = data_size() - (buf - header);
914 int crc = ClassLoader::crc32(0, buf, (jint)sz);
915 return crc;
916 }
917
918 bool FileMapInfo::FileMapHeader::validate() {
919 if (VerifySharedSpaces && compute_crc() != _crc) {
920 fail_continue("Header checksum verification failed.");
921 return false;
922 }
923
924 if (!Arguments::has_jimage()) {
925 FileMapInfo::fail_continue("The shared archive file cannot be used with an exploded module build.");
926 return false;
927 }
928
929 if (_version != current_version()) {
930 FileMapInfo::fail_continue("The shared archive file is the wrong version.");
931 return false;
932 }
933 if (_magic != (int)0xf00baba2) {
934 FileMapInfo::fail_continue("The shared archive file has a bad magic number.");
935 return false;
936 }
937 char header_version[JVM_IDENT_MAX];
938 get_header_version(header_version);
939 if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) {
940 log_info(class, path)("expected: %s", header_version);
941 log_info(class, path)("actual: %s", _jvm_ident);
942 FileMapInfo::fail_continue("The shared archive file was created by a different"
943 " version or build of HotSpot");
944 return false;
945 }
946 if (_obj_alignment != ObjectAlignmentInBytes) {
947 FileMapInfo::fail_continue("The shared archive file's ObjectAlignmentInBytes of %d"
948 " does not equal the current ObjectAlignmentInBytes of " INTX_FORMAT ".",
949 _obj_alignment, ObjectAlignmentInBytes);
950 return false;
951 }
952 if (_compact_strings != CompactStrings) {
953 FileMapInfo::fail_continue("The shared archive file's CompactStrings setting (%s)"
954 " does not equal the current CompactStrings setting (%s).",
955 _compact_strings ? "enabled" : "disabled",
956 CompactStrings ? "enabled" : "disabled");
957 return false;
958 }
959
960 return true;
961 }
962
963 bool FileMapInfo::validate_header() {
964 bool status = _header->validate();
965
966 if (status) {
967 if (!ClassLoader::check_shared_paths_misc_info(_paths_misc_info, _header->_paths_misc_info_size)) {
968 if (!PrintSharedArchiveAndExit) {
969 fail_continue("shared class paths mismatch (hint: enable -Xlog:class+path=info to diagnose the failure)");
970 status = false;
971 }
972 }
973 }
974
975 if (_paths_misc_info != NULL) {
976 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
977 _paths_misc_info = NULL;
978 }
979 return status;
980 }
981
982 // The following method is provided to see whether a given pointer
983 // falls in the mapped shared space.
984 // Param:
985 // p, The given pointer
986 // Return:
987 // True if the p is within the mapped shared space, otherwise, false.
988 bool FileMapInfo::is_in_shared_space(const void* p) {
989 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
990 char *base;
991 if (MetaspaceShared::is_string_region(i) && _header->_space[i]._used == 0) {
992 continue;
993 }
994 base = _header->region_addr(i);
995 if (p >= base && p < base + _header->_space[i]._used) {
996 return true;
997 }
998 }
999
1000 return false;
1001 }
1002
1003 // Check if a given address is within one of the shared regions (ro, rw, md, mc)
1004 bool FileMapInfo::is_in_shared_region(const void* p, int idx) {
1005 assert((idx >= MetaspaceShared::ro) && (idx <= MetaspaceShared::mc), "invalid region index");
1006 char* base = _header->region_addr(idx);
1007 if (p >= base && p < base + _header->_space[idx]._used) {
1008 return true;
1009 }
1010 return false;
1011 }
1012
1013 void FileMapInfo::print_shared_spaces() {
1014 tty->print_cr("Shared Spaces:");
1015 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
1016 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
1017 char *base = _header->region_addr(i);
1018 tty->print(" %s " INTPTR_FORMAT "-" INTPTR_FORMAT,
1019 shared_region_name[i],
1020 p2i(base), p2i(base + si->_used));
1021 }
1022 }
1023
1024 // Unmap mapped regions of shared space.
1025 void FileMapInfo::stop_sharing_and_unmap(const char* msg) {
1026 FileMapInfo *map_info = FileMapInfo::current_info();
1027 if (map_info) {
1028 map_info->fail_continue("%s", msg);
1029 for (int i = 0; i < MetaspaceShared::num_non_strings; i++) {
1030 char *addr = map_info->_header->region_addr(i);
1031 if (addr != NULL && !MetaspaceShared::is_string_region(i)) {
1032 map_info->unmap_region(i);
1033 map_info->_header->_space[i]._addr._base = NULL;
1034 }
1035 }
1036 // Dealloc the string regions only without unmapping. The string regions are part
1037 // of the java heap. Unmapping of the heap regions are managed by GC.
1038 map_info->dealloc_string_regions();
1039 } else if (DumpSharedSpaces) {
1040 fail_stop("%s", msg);
1041 }
1042 }