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