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/stringTable.hpp"
30 #include "classfile/symbolTable.hpp"
31 #include "classfile/systemDictionaryShared.hpp"
32 #include "classfile/altHashing.hpp"
33 #if INCLUDE_ALL_GCS
34 #include "gc/g1/g1CollectedHeap.hpp"
35 #endif
36 #include "logging/log.hpp"
37 #include "logging/logStream.hpp"
38 #include "logging/logMessage.hpp"
39 #include "memory/filemap.hpp"
40 #include "memory/metadataFactory.hpp"
41 #include "memory/metaspaceClosure.hpp"
42 #include "memory/metaspaceShared.hpp"
43 #include "memory/oopFactory.hpp"
44 #include "oops/objArrayOop.hpp"
45 #include "prims/jvm.h"
46 #include "prims/jvmtiExport.hpp"
47 #include "runtime/arguments.hpp"
48 #include "runtime/java.hpp"
49 #include "runtime/os.hpp"
50 #include "runtime/vm_version.hpp"
51 #include "services/memTracker.hpp"
52 #include "utilities/align.hpp"
53 #include "utilities/defaultStream.hpp"
54
55 # include <sys/stat.h>
56 # include <errno.h>
57
58 #ifndef O_BINARY // if defined (Win32) use binary files.
59 #define O_BINARY 0 // otherwise do nothing.
60 #endif
61
62 extern address JVM_FunctionAtStart();
63 extern address JVM_FunctionAtEnd();
64
65 // Complain and stop. All error conditions occurring during the writing of
66 // an archive file should stop the process. Unrecoverable errors during
67 // the reading of the archive file should stop the process.
68
69 static void fail(const char *msg, va_list ap) {
70 // This occurs very early during initialization: tty is not initialized.
71 jio_fprintf(defaultStream::error_stream(),
72 "An error has occurred while processing the"
73 " shared archive file.\n");
74 jio_vfprintf(defaultStream::error_stream(), msg, ap);
75 jio_fprintf(defaultStream::error_stream(), "\n");
76 // Do not change the text of the below message because some tests check for it.
77 vm_exit_during_initialization("Unable to use shared archive.", NULL);
78 }
79
80
81 void FileMapInfo::fail_stop(const char *msg, ...) {
82 va_list ap;
83 va_start(ap, msg);
84 fail(msg, ap); // Never returns.
85 va_end(ap); // for completeness.
86 }
87
88
89 // Complain and continue. Recoverable errors during the reading of the
90 // archive file may continue (with sharing disabled).
91 //
92 // If we continue, then disable shared spaces and close the file.
93
94 void FileMapInfo::fail_continue(const char *msg, ...) {
95 va_list ap;
96 va_start(ap, msg);
97 MetaspaceShared::set_archive_loading_failed();
98 if (PrintSharedArchiveAndExit && _validating_classpath_entry_table) {
99 // If we are doing PrintSharedArchiveAndExit and some of the classpath entries
100 // do not validate, we can still continue "limping" to validate the remaining
101 // entries. No need to quit.
102 tty->print("[");
103 tty->vprint(msg, ap);
104 tty->print_cr("]");
105 } else {
106 if (RequireSharedSpaces) {
107 fail(msg, ap);
108 } else {
109 if (log_is_enabled(Info, cds)) {
110 ResourceMark rm;
111 LogStream ls(Log(cds)::info());
112 ls.print("UseSharedSpaces: ");
113 ls.vprint_cr(msg, ap);
114 }
115 }
116 UseSharedSpaces = false;
117 assert(current_info() != NULL, "singleton must be registered");
118 current_info()->close();
119 }
120 va_end(ap);
121 }
122
123 // Fill in the fileMapInfo structure with data about this VM instance.
124
125 // This method copies the vm version info into header_version. If the version is too
126 // long then a truncated version, which has a hash code appended to it, is copied.
127 //
128 // Using a template enables this method to verify that header_version is an array of
129 // length JVM_IDENT_MAX. This ensures that the code that writes to the CDS file and
130 // the code that reads the CDS file will both use the same size buffer. Hence, will
131 // use identical truncation. This is necessary for matching of truncated versions.
132 template <int N> static void get_header_version(char (&header_version) [N]) {
133 assert(N == JVM_IDENT_MAX, "Bad header_version size");
134
135 const char *vm_version = VM_Version::internal_vm_info_string();
136 const int version_len = (int)strlen(vm_version);
137
138 if (version_len < (JVM_IDENT_MAX-1)) {
139 strcpy(header_version, vm_version);
140
141 } else {
142 // Get the hash value. Use a static seed because the hash needs to return the same
143 // value over multiple jvm invocations.
144 unsigned int hash = AltHashing::murmur3_32(8191, (const jbyte*)vm_version, version_len);
145
146 // Truncate the ident, saving room for the 8 hex character hash value.
147 strncpy(header_version, vm_version, JVM_IDENT_MAX-9);
148
149 // Append the hash code as eight hex digits.
150 sprintf(&header_version[JVM_IDENT_MAX-9], "%08x", hash);
151 header_version[JVM_IDENT_MAX-1] = 0; // Null terminate.
152 }
153 }
154
155 FileMapInfo::FileMapInfo() {
156 assert(_current_info == NULL, "must be singleton"); // not thread safe
157 _current_info = this;
158 memset((void*)this, 0, sizeof(FileMapInfo));
159 _file_offset = 0;
160 _file_open = false;
161 _header = SharedClassUtil::allocate_file_map_header();
162 _header->_version = _invalid_version;
163 }
164
165 FileMapInfo::~FileMapInfo() {
166 assert(_current_info == this, "must be singleton"); // not thread safe
167 _current_info = NULL;
168 }
169
170 void FileMapInfo::populate_header(size_t alignment) {
171 _header->populate(this, alignment);
172 }
173
174 size_t FileMapInfo::FileMapHeader::data_size() {
175 return SharedClassUtil::file_map_header_size() - sizeof(FileMapInfo::FileMapHeaderBase);
176 }
177
178 void FileMapInfo::FileMapHeader::populate(FileMapInfo* mapinfo, size_t alignment) {
179 _magic = 0xf00baba2;
180 _version = _current_version;
181 _alignment = alignment;
182 _obj_alignment = ObjectAlignmentInBytes;
183 _compact_strings = CompactStrings;
184 _narrow_oop_mode = Universe::narrow_oop_mode();
185 _narrow_oop_shift = Universe::narrow_oop_shift();
186 _max_heap_size = MaxHeapSize;
187 _narrow_klass_base = Universe::narrow_klass_base();
188 _narrow_klass_shift = Universe::narrow_klass_shift();
189 _classpath_entry_table_size = mapinfo->_classpath_entry_table_size;
190 _classpath_entry_table = mapinfo->_classpath_entry_table;
191 _classpath_entry_size = mapinfo->_classpath_entry_size;
192
193 // The following fields are for sanity checks for whether this archive
194 // will function correctly with this JVM and the bootclasspath it's
195 // invoked with.
196
197 // JVM version string ... changes on each build.
198 get_header_version(_jvm_ident);
199 }
200
201 void SharedClassPathEntry::init(const char* name, TRAPS) {
202 _timestamp = 0;
203 _filesize = 0;
204
205 struct stat st;
206 if (os::stat(name, &st) == 0) {
207 if ((st.st_mode & S_IFMT) == S_IFDIR) {
208 if (!os::dir_is_empty(name)) {
209 ClassLoader::exit_with_path_failure(
210 "Cannot have non-empty directory in archived classpaths", name);
211 }
212 _is_dir = true;
213 } else {
214 _is_dir = false;
215 _timestamp = st.st_mtime;
216 _filesize = st.st_size;
217 }
218 } else {
219 // The file/dir must exist, or it would not have been added
220 // into ClassLoader::classpath_entry().
221 //
222 // If we can't access a jar file in the boot path, then we can't
223 // make assumptions about where classes get loaded from.
224 FileMapInfo::fail_stop("Unable to open file %s.", name);
225 }
226
227 size_t len = strlen(name) + 1;
228 _name = MetadataFactory::new_array<char>(ClassLoaderData::the_null_class_loader_data(), (int)len, THREAD);
229 strcpy(_name->data(), name);
230 }
231
232 bool SharedClassPathEntry::validate() {
233 struct stat st;
234 const char* name = this->name();
235 bool ok = true;
236 log_info(class, path)("checking shared classpath entry: %s", name);
237 if (os::stat(name, &st) != 0) {
238 FileMapInfo::fail_continue("Required classpath entry does not exist: %s", name);
239 ok = false;
240 } else if (is_dir()) {
241 if (!os::dir_is_empty(name)) {
242 FileMapInfo::fail_continue("directory is not empty: %s", name);
243 ok = false;
244 }
245 } else if (is_jar_or_bootimage()) {
246 if (_timestamp != st.st_mtime ||
247 _filesize != st.st_size) {
248 ok = false;
249 if (PrintSharedArchiveAndExit) {
250 FileMapInfo::fail_continue(_timestamp != st.st_mtime ?
251 "Timestamp mismatch" :
252 "File size mismatch");
253 } else {
254 FileMapInfo::fail_continue("A jar/jimage file is not the one used while building"
255 " the shared archive file: %s", name);
256 }
257 }
258 }
259 return ok;
260 }
261
262 void SharedClassPathEntry::metaspace_pointers_do(MetaspaceClosure* it) {
263 it->push(&_name);
264 it->push(&_manifest);
265 }
266
267 void FileMapInfo::allocate_classpath_entry_table() {
268 Thread* THREAD = Thread::current();
269 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
270 size_t entry_size = SharedClassUtil::shared_class_path_entry_size(); // assert ( should be 8 byte aligned??)
271 int num_entries = ClassLoader::number_of_classpath_entries();
272 size_t bytes = entry_size * num_entries;
273
274 _classpath_entry_table = MetadataFactory::new_array<u8>(loader_data, (int)(bytes + 7 / 8), THREAD);
275 _classpath_entry_table_size = num_entries;
276 _classpath_entry_size = entry_size;
277
278 assert(ClassLoader::get_jrt_entry() != NULL,
279 "No modular java runtime image present when allocating the CDS classpath entry table");
280
281 for (int i=0; i<num_entries; i++) {
282 ClassPathEntry *cpe = ClassLoader::classpath_entry(i);
283 const char* type = ((i == 0) ? "jrt" : (cpe->is_jar_file() ? "jar" : "dir"));
284
285 log_info(class, path)("add main shared path (%s) %s", type, cpe->name());
286 SharedClassPathEntry* ent = shared_classpath(i);
287 ent->init(cpe->name(), THREAD);
288
289 if (i > 0) { // No need to do jimage.
290 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error.
291 SharedClassUtil::update_shared_classpath(cpe, ent, THREAD);
292 }
293 }
294 }
295
296 bool FileMapInfo::validate_classpath_entry_table() {
297 _validating_classpath_entry_table = true;
298
299 int count = _header->_classpath_entry_table_size;
300
301 _classpath_entry_table = _header->_classpath_entry_table;
302 _classpath_entry_size = _header->_classpath_entry_size;
303 _classpath_entry_table_size = _header->_classpath_entry_table_size;
304
305 for (int i=0; i<count; i++) {
306 if (shared_classpath(i)->validate()) {
307 log_info(class, path)("ok");
308 } else if (!PrintSharedArchiveAndExit) {
309 _validating_classpath_entry_table = false;
310 _classpath_entry_table = NULL;
311 _classpath_entry_table_size = 0;
312 return false;
313 }
314 }
315
316 _validating_classpath_entry_table = false;
317 return true;
318 }
319
320
321 // Read the FileMapInfo information from the file.
322
323 bool FileMapInfo::init_from_file(int fd) {
324 size_t sz = _header->data_size();
325 char* addr = _header->data();
326 size_t n = os::read(fd, addr, (unsigned int)sz);
327 if (n != sz) {
328 fail_continue("Unable to read the file header.");
329 return false;
330 }
331 if (_header->_version != current_version()) {
332 fail_continue("The shared archive file has the wrong version.");
333 return false;
334 }
335 _file_offset = (long)n;
336
337 size_t info_size = _header->_paths_misc_info_size;
338 _paths_misc_info = NEW_C_HEAP_ARRAY_RETURN_NULL(char, info_size, mtClass);
339 if (_paths_misc_info == NULL) {
340 fail_continue("Unable to read the file header.");
341 return false;
342 }
343 n = os::read(fd, _paths_misc_info, (unsigned int)info_size);
344 if (n != info_size) {
345 fail_continue("Unable to read the shared path info header.");
346 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
347 _paths_misc_info = NULL;
348 return false;
349 }
350
351 size_t len = lseek(fd, 0, SEEK_END);
352 struct FileMapInfo::FileMapHeader::space_info* si =
353 &_header->_space[MetaspaceShared::last_valid_region];
354 // The last space might be empty
355 if (si->_file_offset > len || len - si->_file_offset < si->_used) {
356 fail_continue("The shared archive file has been truncated.");
357 return false;
358 }
359
360 _file_offset += (long)n;
361 return true;
362 }
363
364
365 // Read the FileMapInfo information from the file.
366 bool FileMapInfo::open_for_read() {
367 _full_path = Arguments::GetSharedArchivePath();
368 int fd = open(_full_path, O_RDONLY | O_BINARY, 0);
369 if (fd < 0) {
370 if (errno == ENOENT) {
371 // Not locating the shared archive is ok.
372 fail_continue("Specified shared archive not found.");
373 } else {
374 fail_continue("Failed to open shared archive file (%s).",
375 os::strerror(errno));
376 }
377 return false;
378 }
379
380 _fd = fd;
381 _file_open = true;
382 return true;
383 }
384
385
386 // Write the FileMapInfo information to the file.
387
388 void FileMapInfo::open_for_write() {
389 _full_path = Arguments::GetSharedArchivePath();
390 if (log_is_enabled(Info, cds)) {
391 ResourceMark rm;
392 LogMessage(cds) msg;
393 stringStream info_stream;
394 info_stream.print_cr("Dumping shared data to file: ");
395 info_stream.print_cr(" %s", _full_path);
396 msg.info("%s", info_stream.as_string());
397 }
398
399 #ifdef _WINDOWS // On Windows, need WRITE permission to remove the file.
400 chmod(_full_path, _S_IREAD | _S_IWRITE);
401 #endif
402
403 // Use remove() to delete the existing file because, on Unix, this will
404 // allow processes that have it open continued access to the file.
405 remove(_full_path);
406 int fd = open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444);
407 if (fd < 0) {
408 fail_stop("Unable to create shared archive file %s: (%s).", _full_path,
409 os::strerror(errno));
410 }
411 _fd = fd;
412 _file_offset = 0;
413 _file_open = true;
414 }
415
416
417 // Write the header to the file, seek to the next allocation boundary.
418
419 void FileMapInfo::write_header() {
420 int info_size = ClassLoader::get_shared_paths_misc_info_size();
421
422 _header->_paths_misc_info_size = info_size;
423
424 align_file_position();
425 size_t sz = _header->data_size();
426 char* addr = _header->data();
427 write_bytes(addr, (int)sz); // skip the C++ vtable
428 write_bytes(ClassLoader::get_shared_paths_misc_info(), info_size);
429 align_file_position();
430 }
431
432
433 // Dump region to file.
434
435 void FileMapInfo::write_region(int region, char* base, size_t size,
436 bool read_only, bool allow_exec) {
437 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[region];
438
439 if (_file_open) {
440 guarantee(si->_file_offset == _file_offset, "file offset mismatch.");
441 log_info(cds)("Shared file region %d: " SIZE_FORMAT_HEX_W(08)
442 " bytes, addr " INTPTR_FORMAT " file offset " SIZE_FORMAT_HEX_W(08),
443 region, size, p2i(base), _file_offset);
444 } else {
445 si->_file_offset = _file_offset;
446 }
447 if (MetaspaceShared::is_heap_region(region)) {
448 assert((base - (char*)Universe::narrow_oop_base()) % HeapWordSize == 0, "Sanity");
449 if (base != NULL) {
450 si->_addr._offset = (intx)oopDesc::encode_heap_oop_not_null((oop)base);
451 } else {
452 si->_addr._offset = 0;
453 }
454 } else {
455 si->_addr._base = base;
456 }
457 si->_used = size;
458 si->_read_only = read_only;
459 si->_allow_exec = allow_exec;
460 si->_crc = ClassLoader::crc32(0, base, (jint)size);
461 write_bytes_aligned(base, (int)size);
462 }
463
464 // Write out the given archive heap memory regions. GC code combines multiple
465 // consequetive archive GC regions into one MemRegion whenever possible and
466 // produces the 'heap_mem' array.
467 //
468 // If the archive heap memory size is smaller than a single dump time GC region
469 // size, there is only one MemRegion in the array.
470 //
471 // If the archive heap memory size is bigger than one dump time GC region size,
472 // the 'heap_mem' array may contain more than one consolidated MemRegions. When
473 // the first/bottom archive GC region is a partial GC region(with the empty
474 // portion at the higher address within the region), one MemRegion is used for
475 // the bottom partial archive GC region. The rest of the consqusective archive
476 // GC regions are combined into another MemRegion.
477 //
478 // Here's the mapping from (archive heap GC regions) -> (GrowableArray<MemRegion> *regions).
479 // + We have 1 or more archive heap regions: ah0, ah1, ah2 ..... ahn
480 // + We have 1 or 2 consolidated heap memory regions: r0 and r1
481 //
482 // If there's a single archive GC region (ah0), then r0 == ah0, and r1 is empty.
483 // Otherwise:
484 //
485 // "X" represented space that's occupied by heap objects.
486 // "_" represented unused spaced in the heap region.
487 //
488 //
489 // |ah0 | ah1 | ah2| ...... | ahn |
490 // |XXXXXX|__ |XXXXX|XXXX|XXXXXXXX|XXXX|
491 // |<-r0->| |<- r1 ----------------->|
492 // ^^^
493 // |
494 // +-- gap
495 size_t FileMapInfo::write_archive_heap_regions(GrowableArray<MemRegion> *heap_mem,
496 int first_region_id, int max_num_regions) {
497 assert(max_num_regions <= 2, "Only support maximum 2 memory regions");
498
499 int arr_len = heap_mem == NULL ? 0 : heap_mem->length();
500 if(arr_len > max_num_regions) {
501 fail_stop("Unable to write archive heap memory regions: "
502 "number of memory regions exceeds maximum due to fragmentation");
503 }
504
505 size_t total_size = 0;
506 for (int i = first_region_id, arr_idx = 0;
507 i < first_region_id + max_num_regions;
508 i++, arr_idx++) {
509 char* start = NULL;
510 size_t size = 0;
511 if (arr_idx < arr_len) {
512 start = (char*)heap_mem->at(arr_idx).start();
513 size = heap_mem->at(arr_idx).byte_size();
514 total_size += size;
515 }
516
517 log_info(cds)("Archive heap region %d " INTPTR_FORMAT " - " INTPTR_FORMAT " = " SIZE_FORMAT_W(8) " bytes",
518 i, p2i(start), p2i(start + size), size);
519 write_region(i, start, size, false, false);
520 }
521 return total_size;
522 }
523
524 // Dump bytes to file -- at the current file position.
525
526 void FileMapInfo::write_bytes(const void* buffer, int nbytes) {
527 if (_file_open) {
528 int n = ::write(_fd, buffer, nbytes);
529 if (n != nbytes) {
530 // It is dangerous to leave the corrupted shared archive file around,
531 // close and remove the file. See bug 6372906.
532 close();
533 remove(_full_path);
534 fail_stop("Unable to write to shared archive file.");
535 }
536 }
537 _file_offset += nbytes;
538 }
539
540
541 // Align file position to an allocation unit boundary.
542
543 void FileMapInfo::align_file_position() {
544 size_t new_file_offset = align_up(_file_offset,
545 os::vm_allocation_granularity());
546 if (new_file_offset != _file_offset) {
547 _file_offset = new_file_offset;
548 if (_file_open) {
549 // Seek one byte back from the target and write a byte to insure
550 // that the written file is the correct length.
551 _file_offset -= 1;
552 if (lseek(_fd, (long)_file_offset, SEEK_SET) < 0) {
553 fail_stop("Unable to seek.");
554 }
555 char zero = 0;
556 write_bytes(&zero, 1);
557 }
558 }
559 }
560
561
562 // Dump bytes to file -- at the current file position.
563
564 void FileMapInfo::write_bytes_aligned(const void* buffer, int nbytes) {
565 align_file_position();
566 write_bytes(buffer, nbytes);
567 align_file_position();
568 }
569
570
571 // Close the shared archive file. This does NOT unmap mapped regions.
572
573 void FileMapInfo::close() {
574 if (_file_open) {
575 if (::close(_fd) < 0) {
576 fail_stop("Unable to close the shared archive file.");
577 }
578 _file_open = false;
579 _fd = -1;
580 }
581 }
582
583
584 // JVM/TI RedefineClasses() support:
585 // Remap the shared readonly space to shared readwrite, private.
586 bool FileMapInfo::remap_shared_readonly_as_readwrite() {
587 int idx = MetaspaceShared::ro;
588 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[idx];
589 if (!si->_read_only) {
590 // the space is already readwrite so we are done
591 return true;
592 }
593 size_t used = si->_used;
594 size_t size = align_up(used, os::vm_allocation_granularity());
595 if (!open_for_read()) {
596 return false;
597 }
598 char *addr = _header->region_addr(idx);
599 char *base = os::remap_memory(_fd, _full_path, si->_file_offset,
600 addr, size, false /* !read_only */,
601 si->_allow_exec);
602 close();
603 if (base == NULL) {
604 fail_continue("Unable to remap shared readonly space (errno=%d).", errno);
605 return false;
606 }
607 if (base != addr) {
608 fail_continue("Unable to remap shared readonly space at required address.");
609 return false;
610 }
611 si->_read_only = false;
612 return true;
613 }
614
615 // Map the whole region at once, assumed to be allocated contiguously.
616 ReservedSpace FileMapInfo::reserve_shared_memory() {
617 char* requested_addr = _header->region_addr(0);
618 size_t size = FileMapInfo::core_spaces_size();
619
620 // Reserve the space first, then map otherwise map will go right over some
621 // other reserved memory (like the code cache).
622 ReservedSpace rs(size, os::vm_allocation_granularity(), false, requested_addr);
623 if (!rs.is_reserved()) {
624 fail_continue("Unable to reserve shared space at required address "
625 INTPTR_FORMAT, p2i(requested_addr));
626 return rs;
627 }
628 // the reserved virtual memory is for mapping class data sharing archive
629 MemTracker::record_virtual_memory_type((address)rs.base(), mtClassShared);
630
631 return rs;
632 }
633
634 // Memory map a region in the address space.
635 static const char* shared_region_name[] = { "MiscData", "ReadWrite", "ReadOnly", "MiscCode", "OptionalData",
636 "String1", "String2", "OpenArchive1", "OpenArchive2" };
637
638 char* FileMapInfo::map_region(int i) {
639 assert(!MetaspaceShared::is_heap_region(i), "sanity");
640 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
641 size_t used = si->_used;
642 size_t alignment = os::vm_allocation_granularity();
643 size_t size = align_up(used, alignment);
644 char *requested_addr = _header->region_addr(i);
645
646 // If a tool agent is in use (debugging enabled), we must map the address space RW
647 if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space()) {
648 si->_read_only = false;
649 }
650
651 // map the contents of the CDS archive in this memory
652 char *base = os::map_memory(_fd, _full_path, si->_file_offset,
653 requested_addr, size, si->_read_only,
654 si->_allow_exec);
655 if (base == NULL || base != requested_addr) {
656 fail_continue("Unable to map %s shared space at required address.", shared_region_name[i]);
657 return NULL;
658 }
659 #ifdef _WINDOWS
660 // This call is Windows-only because the memory_type gets recorded for the other platforms
661 // in method FileMapInfo::reserve_shared_memory(), which is not called on Windows.
662 MemTracker::record_virtual_memory_type((address)base, mtClassShared);
663 #endif
664
665 return base;
666 }
667
668 static MemRegion *string_ranges = NULL;
669 static MemRegion *open_archive_heap_ranges = NULL;
670 static int num_string_ranges = 0;
671 static int num_open_archive_heap_ranges = 0;
672
673 #if INCLUDE_CDS_JAVA_HEAP
674 //
675 // Map the string regions and open archive heap regions to the runtime java
676 // heap.
677 //
678 // The archive string regions are mapped near the runtime java heap top. The
679 // mapped string regions contain no out-going references to any other java heap
680 // regions. GC does not write into the string regions.
681 //
682 // The open archive heap regions are mapped below the string regions in
683 // the runtime java heap. The mapped open archive heap regions may contain
684 // out-going references to the string regions or other java heap regions.
685 // Objects inside the open archive heap regions may be marked by GC and
686 // the references are updated by GC.
687 //
688 void FileMapInfo::map_heap_regions() {
689 if (MetaspaceShared::is_heap_object_archiving_allowed()) {
690 // Check that all the narrow oop and klass encodings match the archive
691 if (narrow_oop_mode() != Universe::narrow_oop_mode() ||
692 narrow_oop_shift() != Universe::narrow_oop_shift() ||
693 narrow_klass_base() != Universe::narrow_klass_base() ||
694 narrow_klass_shift() != Universe::narrow_klass_shift()) {
695 if (log_is_enabled(Info, cds) && _header->_space[MetaspaceShared::first_string]._used > 0) {
696 log_info(cds)("Cached heap data from the CDS archive is being ignored. "
697 "The current CompressedOops/CompressedClassPointers encoding differs from "
698 "that archived due to heap size change. The archive was dumped using max heap "
699 "size " UINTX_FORMAT "M.", max_heap_size()/M);
700 }
701 } else {
702 // First, map string regions as closed archive heap regions.
703 // GC does not write into the regions.
704 if (map_heap_data(&string_ranges,
705 MetaspaceShared::first_string,
706 MetaspaceShared::max_strings,
707 &num_string_ranges)) {
708 StringTable::set_shared_string_mapped();
709
710 // Now, map open_archive heap regions, GC can write into the regions.
711 if (map_heap_data(&open_archive_heap_ranges,
712 MetaspaceShared::first_open_archive_heap_region,
713 MetaspaceShared::max_open_archive_heap_region,
714 &num_open_archive_heap_ranges,
715 true /* open */)) {
716 MetaspaceShared::set_open_archive_heap_region_mapped();
717 }
718 }
719 }
720 } else {
721 if (log_is_enabled(Info, cds) && _header->_space[MetaspaceShared::first_string]._used > 0) {
722 log_info(cds)("Cached heap data from the CDS archive is being ignored. UseG1GC, "
723 "UseCompressedOops and UseCompressedClassPointers are required.");
724 }
725 }
726
727 if (!StringTable::shared_string_mapped()) {
728 assert(string_ranges == NULL && num_string_ranges == 0, "sanity");
729 }
730
731 if (!MetaspaceShared::open_archive_heap_region_mapped()) {
732 assert(open_archive_heap_ranges == NULL && num_open_archive_heap_ranges == 0, "sanity");
733 }
734 }
735
736 bool FileMapInfo::map_heap_data(MemRegion **heap_mem, int first,
737 int max, int* num, bool is_open_archive) {
738 MemRegion * regions = new MemRegion[max];
739 struct FileMapInfo::FileMapHeader::space_info* si;
740 int region_num = 0;
741
742 for (int i = first;
743 i < first + max; i++) {
744 si = &_header->_space[i];
745 size_t used = si->_used;
746 if (used > 0) {
747 size_t size = used;
748 char* requested_addr = (char*)((void*)oopDesc::decode_heap_oop_not_null(
749 (narrowOop)si->_addr._offset));
750 regions[region_num] = MemRegion((HeapWord*)requested_addr, size / HeapWordSize);
751 region_num ++;
752 }
753 }
754
755 if (region_num == 0) {
756 return false; // no archived java heap data
757 }
758
759 // Check that ranges are within the java heap
760 if (!G1CollectedHeap::heap()->check_archive_addresses(regions, region_num)) {
761 if (log_is_enabled(Info, cds)) {
762 log_info(cds)("UseSharedSpaces: Unable to allocate region, "
763 "range is not within java heap.");
764 }
765 return false;
766 }
767
768 // allocate from java heap
769 if (!G1CollectedHeap::heap()->alloc_archive_regions(
770 regions, region_num, is_open_archive)) {
771 if (log_is_enabled(Info, cds)) {
772 log_info(cds)("UseSharedSpaces: Unable to allocate region, "
773 "java heap range is already in use.");
774 }
775 return false;
776 }
777
778 // Map the archived heap data. No need to call MemTracker::record_virtual_memory_type()
779 // for mapped regions as they are part of the reserved java heap, which is
780 // already recorded.
781 for (int i = 0; i < region_num; i++) {
782 si = &_header->_space[first + i];
783 char* addr = (char*)regions[i].start();
784 char* base = os::map_memory(_fd, _full_path, si->_file_offset,
785 addr, regions[i].byte_size(), si->_read_only,
786 si->_allow_exec);
787 if (base == NULL || base != addr) {
788 // dealloc the regions from java heap
789 dealloc_archive_heap_regions(regions, region_num);
790 if (log_is_enabled(Info, cds)) {
791 log_info(cds)("UseSharedSpaces: Unable to map at required address in java heap.");
792 }
793 return false;
794 }
795 }
796
797 if (!verify_mapped_heap_regions(first, region_num)) {
798 // dealloc the regions from java heap
799 dealloc_archive_heap_regions(regions, region_num);
800 if (log_is_enabled(Info, cds)) {
801 log_info(cds)("UseSharedSpaces: mapped heap regions are corrupt");
802 }
803 return false;
804 }
805
806 // the shared heap data is mapped successfully
807 *heap_mem = regions;
808 *num = region_num;
809 return true;
810 }
811
812 bool FileMapInfo::verify_mapped_heap_regions(int first, int num) {
813 for (int i = first;
814 i <= first + num; i++) {
815 if (!verify_region_checksum(i)) {
816 return false;
817 }
818 }
819 return true;
820 }
821
822 void FileMapInfo::fixup_mapped_heap_regions() {
823 // If any string regions were found, call the fill routine to make them parseable.
824 // Note that string_ranges may be non-NULL even if no ranges were found.
825 if (num_string_ranges != 0) {
826 assert(string_ranges != NULL, "Null string_ranges array with non-zero count");
827 G1CollectedHeap::heap()->fill_archive_regions(string_ranges, num_string_ranges);
828 }
829
830 // do the same for mapped open archive heap regions
831 if (num_open_archive_heap_ranges != 0) {
832 assert(open_archive_heap_ranges != NULL, "NULL open_archive_heap_ranges array with non-zero count");
833 G1CollectedHeap::heap()->fill_archive_regions(open_archive_heap_ranges,
834 num_open_archive_heap_ranges);
835 }
836 }
837
838 // dealloc the archive regions from java heap
839 void FileMapInfo::dealloc_archive_heap_regions(MemRegion* regions, int num) {
840 if (num > 0) {
841 assert(regions != NULL, "Null archive ranges array with non-zero count");
842 G1CollectedHeap::heap()->dealloc_archive_regions(regions, num);
843 }
844 }
845 #endif // INCLUDE_CDS_JAVA_HEAP
846
847 bool FileMapInfo::verify_region_checksum(int i) {
848 if (!VerifySharedSpaces) {
849 return true;
850 }
851
852 size_t sz = _header->_space[i]._used;
853
854 if (sz == 0) {
855 return true; // no data
856 }
857 if ((MetaspaceShared::is_string_region(i) &&
858 !StringTable::shared_string_mapped()) ||
859 (MetaspaceShared::is_open_archive_heap_region(i) &&
860 !MetaspaceShared::open_archive_heap_region_mapped())) {
861 return true; // archived heap data is not mapped
862 }
863 const char* buf = _header->region_addr(i);
864 int crc = ClassLoader::crc32(0, buf, (jint)sz);
865 if (crc != _header->_space[i]._crc) {
866 fail_continue("Checksum verification failed.");
867 return false;
868 }
869 return true;
870 }
871
872 // Unmap a memory region in the address space.
873
874 void FileMapInfo::unmap_region(int i) {
875 assert(!MetaspaceShared::is_heap_region(i), "sanity");
876 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
877 size_t used = si->_used;
878 size_t size = align_up(used, os::vm_allocation_granularity());
879
880 if (used == 0) {
881 return;
882 }
883
884 char* addr = _header->region_addr(i);
885 if (!os::unmap_memory(addr, size)) {
886 fail_stop("Unable to unmap shared space.");
887 }
888 }
889
890 void FileMapInfo::assert_mark(bool check) {
891 if (!check) {
892 fail_stop("Mark mismatch while restoring from shared file.");
893 }
894 }
895
896 void FileMapInfo::metaspace_pointers_do(MetaspaceClosure* it) {
897 it->push(&_classpath_entry_table);
898 for (int i=0; i<_classpath_entry_table_size; i++) {
899 shared_classpath(i)->metaspace_pointers_do(it);
900 }
901 }
902
903
904 FileMapInfo* FileMapInfo::_current_info = NULL;
905 Array<u8>* FileMapInfo::_classpath_entry_table = NULL;
906 int FileMapInfo::_classpath_entry_table_size = 0;
907 size_t FileMapInfo::_classpath_entry_size = 0x1234baad;
908 bool FileMapInfo::_validating_classpath_entry_table = false;
909
910 // Open the shared archive file, read and validate the header
911 // information (version, boot classpath, etc.). If initialization
912 // fails, shared spaces are disabled and the file is closed. [See
913 // fail_continue.]
914 //
915 // Validation of the archive is done in two steps:
916 //
917 // [1] validate_header() - done here. This checks the header, including _paths_misc_info.
918 // [2] validate_classpath_entry_table - this is done later, because the table is in the RW
919 // region of the archive, which is not mapped yet.
920 bool FileMapInfo::initialize() {
921 assert(UseSharedSpaces, "UseSharedSpaces expected.");
922
923 if (!open_for_read()) {
924 return false;
925 }
926
927 init_from_file(_fd);
928 if (!validate_header()) {
929 return false;
930 }
931 return true;
932 }
933
934 char* FileMapInfo::FileMapHeader::region_addr(int idx) {
935 if (MetaspaceShared::is_heap_region(idx)) {
936 return _space[idx]._used > 0 ?
937 (char*)((void*)oopDesc::decode_heap_oop_not_null((narrowOop)_space[idx]._addr._offset)) : NULL;
938 } else {
939 return _space[idx]._addr._base;
940 }
941 }
942
943 int FileMapInfo::FileMapHeader::compute_crc() {
944 char* header = data();
945 // start computing from the field after _crc
946 char* buf = (char*)&_crc + sizeof(int);
947 size_t sz = data_size() - (buf - header);
948 int crc = ClassLoader::crc32(0, buf, (jint)sz);
949 return crc;
950 }
951
952 bool FileMapInfo::FileMapHeader::validate() {
953 if (VerifySharedSpaces && compute_crc() != _crc) {
954 fail_continue("Header checksum verification failed.");
955 return false;
956 }
957
958 if (!Arguments::has_jimage()) {
959 FileMapInfo::fail_continue("The shared archive file cannot be used with an exploded module build.");
960 return false;
961 }
962
963 if (_version != current_version()) {
964 FileMapInfo::fail_continue("The shared archive file is the wrong version.");
965 return false;
966 }
967 if (_magic != (int)0xf00baba2) {
968 FileMapInfo::fail_continue("The shared archive file has a bad magic number.");
969 return false;
970 }
971 char header_version[JVM_IDENT_MAX];
972 get_header_version(header_version);
973 if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) {
974 log_info(class, path)("expected: %s", header_version);
975 log_info(class, path)("actual: %s", _jvm_ident);
976 FileMapInfo::fail_continue("The shared archive file was created by a different"
977 " version or build of HotSpot");
978 return false;
979 }
980 if (_obj_alignment != ObjectAlignmentInBytes) {
981 FileMapInfo::fail_continue("The shared archive file's ObjectAlignmentInBytes of %d"
982 " does not equal the current ObjectAlignmentInBytes of " INTX_FORMAT ".",
983 _obj_alignment, ObjectAlignmentInBytes);
984 return false;
985 }
986 if (_compact_strings != CompactStrings) {
987 FileMapInfo::fail_continue("The shared archive file's CompactStrings setting (%s)"
988 " does not equal the current CompactStrings setting (%s).",
989 _compact_strings ? "enabled" : "disabled",
990 CompactStrings ? "enabled" : "disabled");
991 return false;
992 }
993
994 return true;
995 }
996
997 bool FileMapInfo::validate_header() {
998 bool status = _header->validate();
999
1000 if (status) {
1001 if (!ClassLoader::check_shared_paths_misc_info(_paths_misc_info, _header->_paths_misc_info_size)) {
1002 if (!PrintSharedArchiveAndExit) {
1003 fail_continue("shared class paths mismatch (hint: enable -Xlog:class+path=info to diagnose the failure)");
1004 status = false;
1005 }
1006 }
1007 }
1008
1009 if (_paths_misc_info != NULL) {
1010 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
1011 _paths_misc_info = NULL;
1012 }
1013 return status;
1014 }
1015
1016 // The following method is provided to see whether a given pointer
1017 // falls in the mapped shared metadata space.
1018 // Param:
1019 // p, The given pointer
1020 // Return:
1021 // True if the p is within the mapped shared space, otherwise, false.
1022 bool FileMapInfo::is_in_shared_space(const void* p) {
1023 for (int i = 0; i < MetaspaceShared::num_non_heap_spaces; i++) {
1024 char *base;
1025 if (_header->_space[i]._used == 0) {
1026 continue;
1027 }
1028 base = _header->region_addr(i);
1029 if (p >= base && p < base + _header->_space[i]._used) {
1030 return true;
1031 }
1032 }
1033
1034 return false;
1035 }
1036
1037 // Check if a given address is within one of the shared regions
1038 bool FileMapInfo::is_in_shared_region(const void* p, int idx) {
1039 assert(idx == MetaspaceShared::ro ||
1040 idx == MetaspaceShared::rw ||
1041 idx == MetaspaceShared::mc ||
1042 idx == MetaspaceShared::md, "invalid region index");
1043 char* base = _header->region_addr(idx);
1044 if (p >= base && p < base + _header->_space[idx]._used) {
1045 return true;
1046 }
1047 return false;
1048 }
1049
1050 void FileMapInfo::print_shared_spaces() {
1051 tty->print_cr("Shared Spaces:");
1052 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
1053 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
1054 char *base = _header->region_addr(i);
1055 tty->print(" %s " INTPTR_FORMAT "-" INTPTR_FORMAT,
1056 shared_region_name[i],
1057 p2i(base), p2i(base + si->_used));
1058 }
1059 }
1060
1061 // Unmap mapped regions of shared space.
1062 void FileMapInfo::stop_sharing_and_unmap(const char* msg) {
1063 FileMapInfo *map_info = FileMapInfo::current_info();
1064 if (map_info) {
1065 map_info->fail_continue("%s", msg);
1066 for (int i = 0; i < MetaspaceShared::num_non_heap_spaces; i++) {
1067 char *addr = map_info->_header->region_addr(i);
1068 if (addr != NULL && !MetaspaceShared::is_heap_region(i)) {
1069 map_info->unmap_region(i);
1070 map_info->_header->_space[i]._addr._base = NULL;
1071 }
1072 }
1073 // Dealloc the archive heap regions only without unmapping. The regions are part
1074 // of the java heap. Unmapping of the heap regions are managed by GC.
1075 map_info->dealloc_archive_heap_regions(open_archive_heap_ranges,
1076 num_open_archive_heap_ranges);
1077 map_info->dealloc_archive_heap_regions(string_ranges, num_string_ranges);
1078 } else if (DumpSharedSpaces) {
1079 fail_stop("%s", msg);
1080 }
1081 }