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 if (si->_file_offset >= len || len - si->_file_offset < si->_used) {
355 fail_continue("The shared archive file has been truncated.");
356 return false;
357 }
358
359 _file_offset += (long)n;
360 return true;
361 }
362
363
364 // Read the FileMapInfo information from the file.
365 bool FileMapInfo::open_for_read() {
366 _full_path = Arguments::GetSharedArchivePath();
367 int fd = open(_full_path, O_RDONLY | O_BINARY, 0);
368 if (fd < 0) {
369 if (errno == ENOENT) {
370 // Not locating the shared archive is ok.
371 fail_continue("Specified shared archive not found.");
372 } else {
373 fail_continue("Failed to open shared archive file (%s).",
374 os::strerror(errno));
375 }
376 return false;
377 }
378
379 _fd = fd;
380 _file_open = true;
381 return true;
382 }
383
384
385 // Write the FileMapInfo information to the file.
386
387 void FileMapInfo::open_for_write() {
388 _full_path = Arguments::GetSharedArchivePath();
389 if (log_is_enabled(Info, cds)) {
390 ResourceMark rm;
391 LogMessage(cds) msg;
392 stringStream info_stream;
393 info_stream.print_cr("Dumping shared data to file: ");
394 info_stream.print_cr(" %s", _full_path);
395 msg.info("%s", info_stream.as_string());
396 }
397
398 #ifdef _WINDOWS // On Windows, need WRITE permission to remove the file.
399 chmod(_full_path, _S_IREAD | _S_IWRITE);
400 #endif
401
402 // Use remove() to delete the existing file because, on Unix, this will
403 // allow processes that have it open continued access to the file.
404 remove(_full_path);
405 int fd = open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444);
406 if (fd < 0) {
407 fail_stop("Unable to create shared archive file %s: (%s).", _full_path,
408 os::strerror(errno));
409 }
410 _fd = fd;
411 _file_offset = 0;
412 _file_open = true;
413 }
414
415
416 // Write the header to the file, seek to the next allocation boundary.
417
418 void FileMapInfo::write_header() {
419 int info_size = ClassLoader::get_shared_paths_misc_info_size();
420
421 _header->_paths_misc_info_size = info_size;
422
423 align_file_position();
424 size_t sz = _header->data_size();
425 char* addr = _header->data();
426 write_bytes(addr, (int)sz); // skip the C++ vtable
427 write_bytes(ClassLoader::get_shared_paths_misc_info(), info_size);
428 align_file_position();
429 }
430
431
432 // Dump region to file.
433
434 void FileMapInfo::write_region(int region, char* base, size_t size,
435 bool read_only, bool allow_exec) {
436 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[region];
437
438 if (_file_open) {
439 guarantee(si->_file_offset == _file_offset, "file offset mismatch.");
440 log_info(cds)("Shared file region %d: " SIZE_FORMAT_HEX_W(08)
441 " bytes, addr " INTPTR_FORMAT " file offset " SIZE_FORMAT_HEX_W(08),
442 region, size, p2i(base), _file_offset);
443 } else {
444 si->_file_offset = _file_offset;
445 }
446 if (MetaspaceShared::is_string_region(region)) {
447 assert((base - (char*)Universe::narrow_oop_base()) % HeapWordSize == 0, "Sanity");
448 if (base != NULL) {
449 si->_addr._offset = (intx)oopDesc::encode_heap_oop_not_null((oop)base);
450 } else {
451 si->_addr._offset = 0;
452 }
453 } else {
454 si->_addr._base = base;
455 }
456 si->_used = size;
457 si->_read_only = read_only;
458 si->_allow_exec = allow_exec;
459 si->_crc = ClassLoader::crc32(0, base, (jint)size);
460 write_bytes_aligned(base, (int)size);
461 }
462
463 // Write the string space. The string space contains one or multiple GC(G1) regions.
464 // When the total string space size is smaller than one GC region of the dump time,
465 // only one string region is used for shared strings.
466 //
467 // If the total string space size is bigger than one GC region, there would be more
468 // than one GC regions allocated for shared strings. The first/bottom GC region might
469 // be a partial GC region with the empty portion at the higher address within that region.
470 // The non-empty portion of the first region is written into the archive as one string
471 // region. The rest are consecutive full GC regions if they exist, which can be written
472 // out in one chunk as another string region.
473 //
474 // Here's the mapping from (GrowableArray<MemRegion> *regions) -> (metaspace string regions).
475 // + We have 1 or more heap regions: r0, r1, r2 ..... rn
476 // + We have 2 metaspace string regions: s0 and s1
477 //
478 // If there's a single heap region (r0), then s0 == r0, and s1 is empty.
479 // Otherwise:
480 //
481 // "X" represented space that's occupied by heap objects.
482 // "_" represented unused spaced in the heap region.
483 //
484 //
485 // |r0 | r1 | r2 | ...... | rn |
486 // |XXXXXX|__ |XXXXX|XXXX|XXXXXXXX|XXXX|
487 // |<-s0->| |<- s1 ----------------->|
488 // ^^^
489 // |
490 // +-- unmapped space
491 void FileMapInfo::write_string_regions(GrowableArray<MemRegion> *regions,
492 char** st0_start, char** st0_top, char** st0_end,
493 char** st1_start, char** st1_top, char** st1_end) {
494 *st0_start = *st0_top = *st0_end = NULL;
495 *st1_start = *st1_top = *st1_end = NULL;
496
497 assert(MetaspaceShared::max_strings == 2, "this loop doesn't work for any other value");
498 for (int i = MetaspaceShared::first_string;
499 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
500 char* start = NULL;
501 size_t size = 0;
502 int len = regions->length();
503 if (len > 0) {
504 if (i == MetaspaceShared::first_string) {
505 MemRegion first = regions->first();
506 start = (char*)first.start();
507 size = first.byte_size();
508 *st0_start = start;
509 *st0_top = start + size;
510 if (len > 1) {
511 *st0_end = (char*)regions->at(1).start();
512 } else {
513 *st0_end = start + size;
514 }
515 } else {
516 assert(i == MetaspaceShared::first_string + 1, "must be");
517 if (len > 1) {
518 start = (char*)regions->at(1).start();
519 size = (char*)regions->at(len - 1).end() - start;
520 *st1_start = start;
521 *st1_top = start + size;
522 *st1_end = start + size;
523 }
524 }
525 }
526 log_info(cds)("String region %d " INTPTR_FORMAT " - " INTPTR_FORMAT " = " SIZE_FORMAT_W(8) " bytes",
527 i, p2i(start), p2i(start + size), size);
528 write_region(i, start, size, false, false);
529 }
530 }
531
532
533 // Dump bytes to file -- at the current file position.
534
535 void FileMapInfo::write_bytes(const void* buffer, int nbytes) {
536 if (_file_open) {
537 int n = ::write(_fd, buffer, nbytes);
538 if (n != nbytes) {
539 // It is dangerous to leave the corrupted shared archive file around,
540 // close and remove the file. See bug 6372906.
541 close();
542 remove(_full_path);
543 fail_stop("Unable to write to shared archive file.");
544 }
545 }
546 _file_offset += nbytes;
547 }
548
549
550 // Align file position to an allocation unit boundary.
551
552 void FileMapInfo::align_file_position() {
553 size_t new_file_offset = align_up(_file_offset,
554 os::vm_allocation_granularity());
555 if (new_file_offset != _file_offset) {
556 _file_offset = new_file_offset;
557 if (_file_open) {
558 // Seek one byte back from the target and write a byte to insure
559 // that the written file is the correct length.
560 _file_offset -= 1;
561 if (lseek(_fd, (long)_file_offset, SEEK_SET) < 0) {
562 fail_stop("Unable to seek.");
563 }
564 char zero = 0;
565 write_bytes(&zero, 1);
566 }
567 }
568 }
569
570
571 // Dump bytes to file -- at the current file position.
572
573 void FileMapInfo::write_bytes_aligned(const void* buffer, int nbytes) {
574 align_file_position();
575 write_bytes(buffer, nbytes);
576 align_file_position();
577 }
578
579
580 // Close the shared archive file. This does NOT unmap mapped regions.
581
582 void FileMapInfo::close() {
583 if (_file_open) {
584 if (::close(_fd) < 0) {
585 fail_stop("Unable to close the shared archive file.");
586 }
587 _file_open = false;
588 _fd = -1;
589 }
590 }
591
592
593 // JVM/TI RedefineClasses() support:
594 // Remap the shared readonly space to shared readwrite, private.
595 bool FileMapInfo::remap_shared_readonly_as_readwrite() {
596 int idx = MetaspaceShared::ro;
597 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[idx];
598 if (!si->_read_only) {
599 // the space is already readwrite so we are done
600 return true;
601 }
602 size_t used = si->_used;
603 size_t size = align_up(used, os::vm_allocation_granularity());
604 if (!open_for_read()) {
605 return false;
606 }
607 char *addr = _header->region_addr(idx);
608 char *base = os::remap_memory(_fd, _full_path, si->_file_offset,
609 addr, size, false /* !read_only */,
610 si->_allow_exec);
611 close();
612 if (base == NULL) {
613 fail_continue("Unable to remap shared readonly space (errno=%d).", errno);
614 return false;
615 }
616 if (base != addr) {
617 fail_continue("Unable to remap shared readonly space at required address.");
618 return false;
619 }
620 si->_read_only = false;
621 return true;
622 }
623
624 // Map the whole region at once, assumed to be allocated contiguously.
625 ReservedSpace FileMapInfo::reserve_shared_memory() {
626 char* requested_addr = _header->region_addr(0);
627 size_t size = FileMapInfo::core_spaces_size();
628
629 // Reserve the space first, then map otherwise map will go right over some
630 // other reserved memory (like the code cache).
631 ReservedSpace rs(size, os::vm_allocation_granularity(), false, requested_addr);
632 if (!rs.is_reserved()) {
633 fail_continue("Unable to reserve shared space at required address "
634 INTPTR_FORMAT, p2i(requested_addr));
635 return rs;
636 }
637 // the reserved virtual memory is for mapping class data sharing archive
638 MemTracker::record_virtual_memory_type((address)rs.base(), mtClassShared);
639
640 return rs;
641 }
642
643 // Memory map a region in the address space.
644 static const char* shared_region_name[] = { "ReadOnly", "ReadWrite", "MiscData", "MiscCode",
645 "String1", "String2", "OptionalData" };
646
647 char* FileMapInfo::map_region(int i) {
648 assert(!MetaspaceShared::is_string_region(i), "sanity");
649 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
650 size_t used = si->_used;
651 size_t alignment = os::vm_allocation_granularity();
652 size_t size = align_up(used, alignment);
653 char *requested_addr = _header->region_addr(i);
654
655 // If a tool agent is in use (debugging enabled), we must map the address space RW
656 if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space()) {
657 si->_read_only = false;
658 }
659
660 // map the contents of the CDS archive in this memory
661 char *base = os::map_memory(_fd, _full_path, si->_file_offset,
662 requested_addr, size, si->_read_only,
663 si->_allow_exec);
664 if (base == NULL || base != requested_addr) {
665 fail_continue("Unable to map %s shared space at required address.", shared_region_name[i]);
666 return NULL;
667 }
668 #ifdef _WINDOWS
669 // This call is Windows-only because the memory_type gets recorded for the other platforms
670 // in method FileMapInfo::reserve_shared_memory(), which is not called on Windows.
671 MemTracker::record_virtual_memory_type((address)base, mtClassShared);
672 #endif
673
674 return base;
675 }
676
677 static MemRegion *string_ranges = NULL;
678 static int num_ranges = 0;
679 bool FileMapInfo::map_string_regions() {
680 #if INCLUDE_ALL_GCS
681 if (UseG1GC && UseCompressedOops && UseCompressedClassPointers) {
682 // Check that all the narrow oop and klass encodings match the archive
683 if (narrow_oop_mode() != Universe::narrow_oop_mode() ||
684 narrow_oop_shift() != Universe::narrow_oop_shift() ||
685 narrow_klass_base() != Universe::narrow_klass_base() ||
686 narrow_klass_shift() != Universe::narrow_klass_shift()) {
687 if (log_is_enabled(Info, cds) && _header->_space[MetaspaceShared::first_string]._used > 0) {
688 log_info(cds)("Shared string data from the CDS archive is being ignored. "
689 "The current CompressedOops/CompressedClassPointers encoding differs from "
690 "that archived due to heap size change. The archive was dumped using max heap "
691 "size " UINTX_FORMAT "M.", max_heap_size()/M);
692 }
693 } else {
694 string_ranges = new MemRegion[MetaspaceShared::max_strings];
695 struct FileMapInfo::FileMapHeader::space_info* si;
696
697 for (int i = MetaspaceShared::first_string;
698 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
699 si = &_header->_space[i];
700 size_t used = si->_used;
701 if (used > 0) {
702 size_t size = used;
703 char* requested_addr = (char*)((void*)oopDesc::decode_heap_oop_not_null(
704 (narrowOop)si->_addr._offset));
705 string_ranges[num_ranges] = MemRegion((HeapWord*)requested_addr, size / HeapWordSize);
706 num_ranges ++;
707 }
708 }
709
710 if (num_ranges == 0) {
711 StringTable::ignore_shared_strings(true);
712 return true; // no shared string data
713 }
714
715 // Check that ranges are within the java heap
716 if (!G1CollectedHeap::heap()->check_archive_addresses(string_ranges, num_ranges)) {
717 fail_continue("Unable to allocate shared string space: range is not "
718 "within java heap.");
719 return false;
720 }
721
722 // allocate from java heap
723 if (!G1CollectedHeap::heap()->alloc_archive_regions(string_ranges, num_ranges)) {
724 fail_continue("Unable to allocate shared string space: range is "
725 "already in use.");
726 return false;
727 }
728
729 // Map the string data. No need to call MemTracker::record_virtual_memory_type()
730 // for mapped string regions as they are part of the reserved java heap, which
731 // is already recorded.
732 for (int i = 0; i < num_ranges; i++) {
733 si = &_header->_space[MetaspaceShared::first_string + i];
734 char* addr = (char*)string_ranges[i].start();
735 char* base = os::map_memory(_fd, _full_path, si->_file_offset,
736 addr, string_ranges[i].byte_size(), si->_read_only,
737 si->_allow_exec);
738 if (base == NULL || base != addr) {
739 // dealloc the string regions from java heap
740 dealloc_string_regions();
741 fail_continue("Unable to map shared string space at required address.");
742 return false;
743 }
744 }
745
746 if (!verify_string_regions()) {
747 // dealloc the string regions from java heap
748 dealloc_string_regions();
749 fail_continue("Shared string regions are corrupt");
750 return false;
751 }
752
753 // the shared string data is mapped successfully
754 return true;
755 }
756 } else {
757 if (log_is_enabled(Info, cds) && _header->_space[MetaspaceShared::first_string]._used > 0) {
758 log_info(cds)("Shared string data from the CDS archive is being ignored. UseG1GC, "
759 "UseCompressedOops and UseCompressedClassPointers are required.");
760 }
761 }
762
763 // if we get here, the shared string data is not mapped
764 assert(string_ranges == NULL && num_ranges == 0, "sanity");
765 StringTable::ignore_shared_strings(true);
766 #endif
767 return true;
768 }
769
770 bool FileMapInfo::verify_string_regions() {
771 for (int i = MetaspaceShared::first_string;
772 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
773 if (!verify_region_checksum(i)) {
774 return false;
775 }
776 }
777 return true;
778 }
779
780 void FileMapInfo::fixup_string_regions() {
781 #if INCLUDE_ALL_GCS
782 // If any string regions were found, call the fill routine to make them parseable.
783 // Note that string_ranges may be non-NULL even if no ranges were found.
784 if (num_ranges != 0) {
785 assert(string_ranges != NULL, "Null string_ranges array with non-zero count");
786 G1CollectedHeap::heap()->fill_archive_regions(string_ranges, num_ranges);
787 }
788 #endif
789 }
790
791 bool FileMapInfo::verify_region_checksum(int i) {
792 if (!VerifySharedSpaces) {
793 return true;
794 }
795
796 size_t sz = _header->_space[i]._used;
797
798 if (sz == 0) {
799 return true; // no data
800 }
801 if (MetaspaceShared::is_string_region(i) && StringTable::shared_string_ignored()) {
802 return true; // shared string data are not mapped
803 }
804 const char* buf = _header->region_addr(i);
805 int crc = ClassLoader::crc32(0, buf, (jint)sz);
806 if (crc != _header->_space[i]._crc) {
807 fail_continue("Checksum verification failed.");
808 return false;
809 }
810 return true;
811 }
812
813 // Unmap a memory region in the address space.
814
815 void FileMapInfo::unmap_region(int i) {
816 assert(!MetaspaceShared::is_string_region(i), "sanity");
817 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
818 size_t used = si->_used;
819 size_t size = align_up(used, os::vm_allocation_granularity());
820
821 if (used == 0) {
822 return;
823 }
824
825 char* addr = _header->region_addr(i);
826 if (!os::unmap_memory(addr, size)) {
827 fail_stop("Unable to unmap shared space.");
828 }
829 }
830
831 // dealloc the archived string region from java heap
832 void FileMapInfo::dealloc_string_regions() {
833 #if INCLUDE_ALL_GCS
834 if (num_ranges > 0) {
835 assert(string_ranges != NULL, "Null string_ranges array with non-zero count");
836 G1CollectedHeap::heap()->dealloc_archive_regions(string_ranges, num_ranges);
837 }
838 #endif
839 }
840
841 void FileMapInfo::assert_mark(bool check) {
842 if (!check) {
843 fail_stop("Mark mismatch while restoring from shared file.");
844 }
845 }
846
847 void FileMapInfo::metaspace_pointers_do(MetaspaceClosure* it) {
848 it->push(&_classpath_entry_table);
849 for (int i=0; i<_classpath_entry_table_size; i++) {
850 shared_classpath(i)->metaspace_pointers_do(it);
851 }
852 }
853
854
855 FileMapInfo* FileMapInfo::_current_info = NULL;
856 Array<u8>* FileMapInfo::_classpath_entry_table = NULL;
857 int FileMapInfo::_classpath_entry_table_size = 0;
858 size_t FileMapInfo::_classpath_entry_size = 0x1234baad;
859 bool FileMapInfo::_validating_classpath_entry_table = false;
860
861 // Open the shared archive file, read and validate the header
862 // information (version, boot classpath, etc.). If initialization
863 // fails, shared spaces are disabled and the file is closed. [See
864 // fail_continue.]
865 //
866 // Validation of the archive is done in two steps:
867 //
868 // [1] validate_header() - done here. This checks the header, including _paths_misc_info.
869 // [2] validate_classpath_entry_table - this is done later, because the table is in the RW
870 // region of the archive, which is not mapped yet.
871 bool FileMapInfo::initialize() {
872 assert(UseSharedSpaces, "UseSharedSpaces expected.");
873
874 if (!open_for_read()) {
875 return false;
876 }
877
878 init_from_file(_fd);
879 if (!validate_header()) {
880 return false;
881 }
882 return true;
883 }
884
885 char* FileMapInfo::FileMapHeader::region_addr(int idx) {
886 if (MetaspaceShared::is_string_region(idx)) {
887 return (char*)((void*)oopDesc::decode_heap_oop_not_null(
888 (narrowOop)_space[idx]._addr._offset));
889 } else {
890 return _space[idx]._addr._base;
891 }
892 }
893
894 int FileMapInfo::FileMapHeader::compute_crc() {
895 char* header = data();
896 // start computing from the field after _crc
897 char* buf = (char*)&_crc + sizeof(int);
898 size_t sz = data_size() - (buf - header);
899 int crc = ClassLoader::crc32(0, buf, (jint)sz);
900 return crc;
901 }
902
903 bool FileMapInfo::FileMapHeader::validate() {
904 if (VerifySharedSpaces && compute_crc() != _crc) {
905 fail_continue("Header checksum verification failed.");
906 return false;
907 }
908
909 if (!Arguments::has_jimage()) {
910 FileMapInfo::fail_continue("The shared archive file cannot be used with an exploded module build.");
911 return false;
912 }
913
914 if (_version != current_version()) {
915 FileMapInfo::fail_continue("The shared archive file is the wrong version.");
916 return false;
917 }
918 if (_magic != (int)0xf00baba2) {
919 FileMapInfo::fail_continue("The shared archive file has a bad magic number.");
920 return false;
921 }
922 char header_version[JVM_IDENT_MAX];
923 get_header_version(header_version);
924 if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) {
925 log_info(class, path)("expected: %s", header_version);
926 log_info(class, path)("actual: %s", _jvm_ident);
927 FileMapInfo::fail_continue("The shared archive file was created by a different"
928 " version or build of HotSpot");
929 return false;
930 }
931 if (_obj_alignment != ObjectAlignmentInBytes) {
932 FileMapInfo::fail_continue("The shared archive file's ObjectAlignmentInBytes of %d"
933 " does not equal the current ObjectAlignmentInBytes of " INTX_FORMAT ".",
934 _obj_alignment, ObjectAlignmentInBytes);
935 return false;
936 }
937 if (_compact_strings != CompactStrings) {
938 FileMapInfo::fail_continue("The shared archive file's CompactStrings setting (%s)"
939 " does not equal the current CompactStrings setting (%s).",
940 _compact_strings ? "enabled" : "disabled",
941 CompactStrings ? "enabled" : "disabled");
942 return false;
943 }
944
945 return true;
946 }
947
948 bool FileMapInfo::validate_header() {
949 bool status = _header->validate();
950
951 if (status) {
952 if (!ClassLoader::check_shared_paths_misc_info(_paths_misc_info, _header->_paths_misc_info_size)) {
953 if (!PrintSharedArchiveAndExit) {
954 fail_continue("shared class paths mismatch (hint: enable -Xlog:class+path=info to diagnose the failure)");
955 status = false;
956 }
957 }
958 }
959
960 if (_paths_misc_info != NULL) {
961 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
962 _paths_misc_info = NULL;
963 }
964 return status;
965 }
966
967 // The following method is provided to see whether a given pointer
968 // falls in the mapped shared space.
969 // Param:
970 // p, The given pointer
971 // Return:
972 // True if the p is within the mapped shared space, otherwise, false.
973 bool FileMapInfo::is_in_shared_space(const void* p) {
974 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
975 char *base;
976 if (MetaspaceShared::is_string_region(i) && _header->_space[i]._used == 0) {
977 continue;
978 }
979 base = _header->region_addr(i);
980 if (p >= base && p < base + _header->_space[i]._used) {
981 return true;
982 }
983 }
984
985 return false;
986 }
987
988 // Check if a given address is within one of the shared regions ( ro, rw, mc or md)
989 bool FileMapInfo::is_in_shared_region(const void* p, int idx) {
990 assert(idx == MetaspaceShared::ro ||
991 idx == MetaspaceShared::rw ||
992 idx == MetaspaceShared::mc ||
993 idx == MetaspaceShared::md, "invalid region index");
994 char* base = _header->region_addr(idx);
995 if (p >= base && p < base + _header->_space[idx]._used) {
996 return true;
997 }
998 return false;
999 }
1000
1001 void FileMapInfo::print_shared_spaces() {
1002 tty->print_cr("Shared Spaces:");
1003 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
1004 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
1005 char *base = _header->region_addr(i);
1006 tty->print(" %s " INTPTR_FORMAT "-" INTPTR_FORMAT,
1007 shared_region_name[i],
1008 p2i(base), p2i(base + si->_used));
1009 }
1010 }
1011
1012 // Unmap mapped regions of shared space.
1013 void FileMapInfo::stop_sharing_and_unmap(const char* msg) {
1014 FileMapInfo *map_info = FileMapInfo::current_info();
1015 if (map_info) {
1016 map_info->fail_continue("%s", msg);
1017 for (int i = 0; i < MetaspaceShared::num_non_strings; i++) {
1018 char *addr = map_info->_header->region_addr(i);
1019 if (addr != NULL && !MetaspaceShared::is_string_region(i)) {
1020 map_info->unmap_region(i);
1021 map_info->_header->_space[i]._addr._base = NULL;
1022 }
1023 }
1024 // Dealloc the string regions only without unmapping. The string regions are part
1025 // of the java heap. Unmapping of the heap regions are managed by GC.
1026 map_info->dealloc_string_regions();
1027 } else if (DumpSharedSpaces) {
1028 fail_stop("%s", msg);
1029 }
1030 }