1 /*
2 * Copyright (c) 2003, 2017, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/classLoader.hpp"
27 #include "classfile/compactHashtable.inline.hpp"
28 #include "classfile/sharedClassUtil.hpp"
29 #include "classfile/symbolTable.hpp"
30 #include "classfile/systemDictionaryShared.hpp"
31 #include "classfile/altHashing.hpp"
32 #if INCLUDE_ALL_GCS
33 #include "gc/g1/g1CollectedHeap.hpp"
34 #endif
35 #include "logging/log.hpp"
36 #include "logging/logStream.hpp"
37 #include "logging/logMessage.hpp"
38 #include "memory/filemap.hpp"
39 #include "memory/metadataFactory.hpp"
40 #include "memory/metaspaceClosure.hpp"
41 #include "memory/metaspaceShared.hpp"
42 #include "memory/oopFactory.hpp"
43 #include "oops/objArrayOop.hpp"
44 #include "prims/jvm.h"
45 #include "prims/jvmtiExport.hpp"
46 #include "runtime/arguments.hpp"
47 #include "runtime/java.hpp"
48 #include "runtime/os.hpp"
49 #include "runtime/vm_version.hpp"
50 #include "services/memTracker.hpp"
51 #include "utilities/align.hpp"
52 #include "utilities/defaultStream.hpp"
53
54 # include <sys/stat.h>
55 # include <errno.h>
56
57 #ifndef O_BINARY // if defined (Win32) use binary files.
58 #define O_BINARY 0 // otherwise do nothing.
59 #endif
60
61 extern address JVM_FunctionAtStart();
62 extern address JVM_FunctionAtEnd();
63
64 // Complain and stop. All error conditions occurring during the writing of
65 // an archive file should stop the process. Unrecoverable errors during
66 // the reading of the archive file should stop the process.
67
68 static void fail(const char *msg, va_list ap) {
69 // This occurs very early during initialization: tty is not initialized.
70 jio_fprintf(defaultStream::error_stream(),
71 "An error has occurred while processing the"
72 " shared archive file.\n");
73 jio_vfprintf(defaultStream::error_stream(), msg, ap);
74 jio_fprintf(defaultStream::error_stream(), "\n");
75 // Do not change the text of the below message because some tests check for it.
76 vm_exit_during_initialization("Unable to use shared archive.", NULL);
77 }
78
79
80 void FileMapInfo::fail_stop(const char *msg, ...) {
81 va_list ap;
82 va_start(ap, msg);
83 fail(msg, ap); // Never returns.
84 va_end(ap); // for completeness.
85 }
86
87
88 // Complain and continue. Recoverable errors during the reading of the
89 // archive file may continue (with sharing disabled).
90 //
91 // If we continue, then disable shared spaces and close the file.
92
93 void FileMapInfo::fail_continue(const char *msg, ...) {
94 va_list ap;
95 va_start(ap, msg);
96 MetaspaceShared::set_archive_loading_failed();
97 if (PrintSharedArchiveAndExit && _validating_classpath_entry_table) {
98 // If we are doing PrintSharedArchiveAndExit and some of the classpath entries
99 // do not validate, we can still continue "limping" to validate the remaining
100 // entries. No need to quit.
101 tty->print("[");
102 tty->vprint(msg, ap);
103 tty->print_cr("]");
104 } else {
105 if (RequireSharedSpaces) {
106 fail(msg, ap);
107 } else {
108 if (log_is_enabled(Info, cds)) {
109 ResourceMark rm;
110 LogStream ls(Log(cds)::info());
111 ls.print("UseSharedSpaces: ");
112 ls.vprint_cr(msg, ap);
113 }
114 }
115 UseSharedSpaces = false;
116 assert(current_info() != NULL, "singleton must be registered");
117 current_info()->close();
118 }
119 va_end(ap);
120 }
121
122 // Fill in the fileMapInfo structure with data about this VM instance.
123
124 // This method copies the vm version info into header_version. If the version is too
125 // long then a truncated version, which has a hash code appended to it, is copied.
126 //
127 // Using a template enables this method to verify that header_version is an array of
128 // length JVM_IDENT_MAX. This ensures that the code that writes to the CDS file and
129 // the code that reads the CDS file will both use the same size buffer. Hence, will
130 // use identical truncation. This is necessary for matching of truncated versions.
131 template <int N> static void get_header_version(char (&header_version) [N]) {
132 assert(N == JVM_IDENT_MAX, "Bad header_version size");
133
134 const char *vm_version = VM_Version::internal_vm_info_string();
135 const int version_len = (int)strlen(vm_version);
136
137 if (version_len < (JVM_IDENT_MAX-1)) {
138 strcpy(header_version, vm_version);
139
140 } else {
141 // Get the hash value. Use a static seed because the hash needs to return the same
142 // value over multiple jvm invocations.
143 unsigned int hash = AltHashing::murmur3_32(8191, (const jbyte*)vm_version, version_len);
144
145 // Truncate the ident, saving room for the 8 hex character hash value.
146 strncpy(header_version, vm_version, JVM_IDENT_MAX-9);
147
148 // Append the hash code as eight hex digits.
149 sprintf(&header_version[JVM_IDENT_MAX-9], "%08x", hash);
150 header_version[JVM_IDENT_MAX-1] = 0; // Null terminate.
151 }
152 }
153
154 FileMapInfo::FileMapInfo() {
155 assert(_current_info == NULL, "must be singleton"); // not thread safe
156 _current_info = this;
157 memset((void*)this, 0, sizeof(FileMapInfo));
158 _file_offset = 0;
159 _file_open = false;
160 _header = SharedClassUtil::allocate_file_map_header();
161 _header->_version = _invalid_version;
162 }
163
164 FileMapInfo::~FileMapInfo() {
165 assert(_current_info == this, "must be singleton"); // not thread safe
166 _current_info = NULL;
167 }
168
169 void FileMapInfo::populate_header(size_t alignment) {
170 _header->populate(this, alignment);
171 }
172
173 size_t FileMapInfo::FileMapHeader::data_size() {
174 return SharedClassUtil::file_map_header_size() - sizeof(FileMapInfo::FileMapHeaderBase);
175 }
176
177 void FileMapInfo::FileMapHeader::populate(FileMapInfo* mapinfo, size_t alignment) {
178 _magic = 0xf00baba2;
179 _version = _current_version;
180 _alignment = alignment;
181 _obj_alignment = ObjectAlignmentInBytes;
182 _compact_strings = CompactStrings;
183 _narrow_oop_mode = Universe::narrow_oop_mode();
184 _narrow_oop_shift = Universe::narrow_oop_shift();
185 _max_heap_size = MaxHeapSize;
186 _narrow_klass_base = Universe::narrow_klass_base();
187 _narrow_klass_shift = Universe::narrow_klass_shift();
188 _classpath_entry_table_size = mapinfo->_classpath_entry_table_size;
189 _classpath_entry_table = mapinfo->_classpath_entry_table;
190 _classpath_entry_size = mapinfo->_classpath_entry_size;
191
192 // The following fields are for sanity checks for whether this archive
193 // will function correctly with this JVM and the bootclasspath it's
194 // invoked with.
195
196 // JVM version string ... changes on each build.
197 get_header_version(_jvm_ident);
198 }
199
200 void SharedClassPathEntry::init(const char* name, TRAPS) {
201 _timestamp = 0;
202 _filesize = 0;
203
204 struct stat st;
205 if (os::stat(name, &st) == 0) {
206 if ((st.st_mode & S_IFMT) == S_IFDIR) {
207 if (!os::dir_is_empty(name)) {
208 ClassLoader::exit_with_path_failure(
209 "Cannot have non-empty directory in archived classpaths", name);
210 }
211 _is_dir = true;
212 } else {
213 _is_dir = false;
214 _timestamp = st.st_mtime;
215 _filesize = st.st_size;
216 }
217 } else {
218 // The file/dir must exist, or it would not have been added
219 // into ClassLoader::classpath_entry().
220 //
221 // If we can't access a jar file in the boot path, then we can't
222 // make assumptions about where classes get loaded from.
223 FileMapInfo::fail_stop("Unable to open file %s.", name);
224 }
225
226 size_t len = strlen(name) + 1;
227 _name = MetadataFactory::new_array<char>(ClassLoaderData::the_null_class_loader_data(), (int)len, THREAD);
228 strcpy(_name->data(), name);
229 }
230
231 bool SharedClassPathEntry::validate() {
232 struct stat st;
233 const char* name = this->name();
234 bool ok = true;
235 log_info(class, path)("checking shared classpath entry: %s", name);
236 if (os::stat(name, &st) != 0) {
237 FileMapInfo::fail_continue("Required classpath entry does not exist: %s", name);
238 ok = false;
239 } else if (is_dir()) {
240 if (!os::dir_is_empty(name)) {
241 FileMapInfo::fail_continue("directory is not empty: %s", name);
242 ok = false;
243 }
244 } else if (is_jar_or_bootimage()) {
245 if (_timestamp != st.st_mtime ||
246 _filesize != st.st_size) {
247 ok = false;
248 if (PrintSharedArchiveAndExit) {
249 FileMapInfo::fail_continue(_timestamp != st.st_mtime ?
250 "Timestamp mismatch" :
251 "File size mismatch");
252 } else {
253 FileMapInfo::fail_continue("A jar/jimage file is not the one used while building"
254 " the shared archive file: %s", name);
255 }
256 }
257 }
258 return ok;
259 }
260
261 void SharedClassPathEntry::metaspace_pointers_do(MetaspaceClosure* it) {
262 it->push(&_name);
263 it->push(&_manifest);
264 }
265
266 void FileMapInfo::allocate_classpath_entry_table() {
267 Thread* THREAD = Thread::current();
268 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
269 size_t entry_size = SharedClassUtil::shared_class_path_entry_size(); // assert ( should be 8 byte aligned??)
270 int num_entries = ClassLoader::number_of_classpath_entries();
271 size_t bytes = entry_size * num_entries;
272
273 _classpath_entry_table = MetadataFactory::new_array<u8>(loader_data, (int)(bytes + 7 / 8), THREAD);
274 _classpath_entry_table_size = num_entries;
275 _classpath_entry_size = entry_size;
276
277 assert(ClassLoader::get_jrt_entry() != NULL,
278 "No modular java runtime image present when allocating the CDS classpath entry table");
279
280 for (int i=0; i<num_entries; i++) {
281 ClassPathEntry *cpe = ClassLoader::classpath_entry(i);
282 const char* type = ((i == 0) ? "jrt" : (cpe->is_jar_file() ? "jar" : "dir"));
283
284 log_info(class, path)("add main shared path (%s) %s", type, cpe->name());
285 SharedClassPathEntry* ent = shared_classpath(i);
286 ent->init(cpe->name(), THREAD);
287
288 if (i > 0) { // No need to do jimage.
289 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error.
290 SharedClassUtil::update_shared_classpath(cpe, ent, THREAD);
291 }
292 }
293 }
294
295 bool FileMapInfo::validate_classpath_entry_table() {
296 _validating_classpath_entry_table = true;
297
298 int count = _header->_classpath_entry_table_size;
299
300 _classpath_entry_table = _header->_classpath_entry_table;
301 _classpath_entry_size = _header->_classpath_entry_size;
302 _classpath_entry_table_size = _header->_classpath_entry_table_size;
303
304 for (int i=0; i<count; i++) {
305 if (shared_classpath(i)->validate()) {
306 log_info(class, path)("ok");
307 } else if (!PrintSharedArchiveAndExit) {
308 _validating_classpath_entry_table = false;
309 _classpath_entry_table = NULL;
310 _classpath_entry_table_size = 0;
311 return false;
312 }
313 }
314
315 _validating_classpath_entry_table = false;
316 return true;
317 }
318
319
320 // Read the FileMapInfo information from the file.
321
322 bool FileMapInfo::init_from_file(int fd) {
323 size_t sz = _header->data_size();
324 char* addr = _header->data();
325 size_t n = os::read(fd, addr, (unsigned int)sz);
326 if (n != sz) {
327 fail_continue("Unable to read the file header.");
328 return false;
329 }
330 if (_header->_version != current_version()) {
331 fail_continue("The shared archive file has the wrong version.");
332 return false;
333 }
334 _file_offset = (long)n;
335
336 size_t info_size = _header->_paths_misc_info_size;
337 _paths_misc_info = NEW_C_HEAP_ARRAY_RETURN_NULL(char, info_size, mtClass);
338 if (_paths_misc_info == NULL) {
339 fail_continue("Unable to read the file header.");
340 return false;
341 }
342 n = os::read(fd, _paths_misc_info, (unsigned int)info_size);
343 if (n != info_size) {
344 fail_continue("Unable to read the shared path info header.");
345 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
346 _paths_misc_info = NULL;
347 return false;
348 }
349
350 size_t len = lseek(fd, 0, SEEK_END);
351 struct FileMapInfo::FileMapHeader::space_info* si =
352 &_header->_space[MetaspaceShared::last_valid_region];
353 if (si->_file_offset >= len || len - si->_file_offset < si->_used) {
354 fail_continue("The shared archive file has been truncated.");
355 return false;
356 }
357
358 _file_offset += (long)n;
359 return true;
360 }
361
362
363 // Read the FileMapInfo information from the file.
364 bool FileMapInfo::open_for_read() {
365 _full_path = Arguments::GetSharedArchivePath();
366 int fd = open(_full_path, O_RDONLY | O_BINARY, 0);
367 if (fd < 0) {
368 if (errno == ENOENT) {
369 // Not locating the shared archive is ok.
370 fail_continue("Specified shared archive not found.");
371 } else {
372 fail_continue("Failed to open shared archive file (%s).",
373 os::strerror(errno));
374 }
375 return false;
376 }
377
378 _fd = fd;
379 _file_open = true;
380 return true;
381 }
382
383
384 // Write the FileMapInfo information to the file.
385
386 void FileMapInfo::open_for_write() {
387 _full_path = Arguments::GetSharedArchivePath();
388 if (log_is_enabled(Info, cds)) {
389 ResourceMark rm;
390 LogMessage(cds) msg;
391 stringStream info_stream;
392 info_stream.print_cr("Dumping shared data to file: ");
393 info_stream.print_cr(" %s", _full_path);
394 msg.info("%s", info_stream.as_string());
395 }
396
397 #ifdef _WINDOWS // On Windows, need WRITE permission to remove the file.
398 chmod(_full_path, _S_IREAD | _S_IWRITE);
399 #endif
400
401 // Use remove() to delete the existing file because, on Unix, this will
402 // allow processes that have it open continued access to the file.
403 remove(_full_path);
404 int fd = open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444);
405 if (fd < 0) {
406 fail_stop("Unable to create shared archive file %s: (%s).", _full_path,
407 os::strerror(errno));
408 }
409 _fd = fd;
410 _file_offset = 0;
411 _file_open = true;
412 }
413
414
415 // Write the header to the file, seek to the next allocation boundary.
416
417 void FileMapInfo::write_header() {
418 int info_size = ClassLoader::get_shared_paths_misc_info_size();
419
420 _header->_paths_misc_info_size = info_size;
421
422 align_file_position();
423 size_t sz = _header->data_size();
424 char* addr = _header->data();
425 write_bytes(addr, (int)sz); // skip the C++ vtable
426 write_bytes(ClassLoader::get_shared_paths_misc_info(), info_size);
427 align_file_position();
428 }
429
430
431 // Dump region to file.
432
433 void FileMapInfo::write_region(int region, char* base, size_t size,
434 bool read_only, bool allow_exec) {
435 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[region];
436
437 if (_file_open) {
438 guarantee(si->_file_offset == _file_offset, "file offset mismatch.");
439 log_info(cds)("Shared file region %d: " SIZE_FORMAT_HEX_W(08)
440 " bytes, addr " INTPTR_FORMAT " file offset " SIZE_FORMAT_HEX_W(08),
441 region, size, p2i(base), _file_offset);
442 } else {
443 si->_file_offset = _file_offset;
444 }
445 if (MetaspaceShared::is_string_region(region)) {
446 assert((base - (char*)Universe::narrow_oop_base()) % HeapWordSize == 0, "Sanity");
447 if (base != NULL) {
448 si->_addr._offset = (intx)oopDesc::encode_heap_oop_not_null((oop)base);
449 } else {
450 si->_addr._offset = 0;
451 }
452 } else {
453 si->_addr._base = base;
454 }
455 si->_used = size;
456 si->_read_only = read_only;
457 si->_allow_exec = allow_exec;
458 si->_crc = ClassLoader::crc32(0, base, (jint)size);
459 write_bytes_aligned(base, (int)size);
460 }
461
462 // Write the string space. The string space contains one or multiple GC(G1) regions.
463 // When the total string space size is smaller than one GC region of the dump time,
464 // only one string region is used for shared strings.
465 //
466 // If the total string space size is bigger than one GC region, there would be more
467 // than one GC regions allocated for shared strings. The first/bottom GC region might
468 // be a partial GC region with the empty portion at the higher address within that region.
469 // The non-empty portion of the first region is written into the archive as one string
470 // region. The rest are consecutive full GC regions if they exist, which can be written
471 // out in one chunk as another string region.
472 //
473 // Here's the mapping from (GrowableArray<MemRegion> *regions) -> (metaspace string regions).
474 // + We have 1 or more heap regions: r0, r1, r2 ..... rn
475 // + We have 2 metaspace string regions: s0 and s1
476 //
477 // If there's a single heap region (r0), then s0 == r0, and s1 is empty.
478 // Otherwise:
479 //
480 // "X" represented space that's occupied by heap objects.
481 // "_" represented unused spaced in the heap region.
482 //
483 //
484 // |r0 | r1 | r2 | ...... | rn |
485 // |XXXXXX|__ |XXXXX|XXXX|XXXXXXXX|XXXX|
486 // |<-s0->| |<- s1 ----------------->|
487 // ^^^
488 // |
489 // +-- unmapped space
490 void FileMapInfo::write_string_regions(GrowableArray<MemRegion> *regions,
491 char** st0_start, char** st0_top, char** st0_end,
492 char** st1_start, char** st1_top, char** st1_end) {
493 *st0_start = *st0_top = *st0_end = NULL;
494 *st1_start = *st1_top = *st1_end = NULL;
495
496 assert(MetaspaceShared::max_strings == 2, "this loop doesn't work for any other value");
497 for (int i = MetaspaceShared::first_string;
498 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
499 char* start = NULL;
500 size_t size = 0;
501 int len = regions->length();
502 if (len > 0) {
503 if (i == MetaspaceShared::first_string) {
504 MemRegion first = regions->first();
505 start = (char*)first.start();
506 size = first.byte_size();
507 *st0_start = start;
508 *st0_top = start + size;
509 if (len > 1) {
510 *st0_end = (char*)regions->at(1).start();
511 } else {
512 *st0_end = start + size;
513 }
514 } else {
515 assert(i == MetaspaceShared::first_string + 1, "must be");
516 if (len > 1) {
517 start = (char*)regions->at(1).start();
518 size = (char*)regions->at(len - 1).end() - start;
519 *st1_start = start;
520 *st1_top = start + size;
521 *st1_end = start + size;
522 }
523 }
524 }
525 log_info(cds)("String region %d " INTPTR_FORMAT " - " INTPTR_FORMAT " = " SIZE_FORMAT_W(8) " bytes",
526 i, p2i(start), p2i(start + size), size);
527 write_region(i, start, size, false, false);
528 }
529 }
530
531
532 // Dump bytes to file -- at the current file position.
533
534 void FileMapInfo::write_bytes(const void* buffer, int nbytes) {
535 if (_file_open) {
536 int n = ::write(_fd, buffer, nbytes);
537 if (n != nbytes) {
538 // It is dangerous to leave the corrupted shared archive file around,
539 // close and remove the file. See bug 6372906.
540 close();
541 remove(_full_path);
542 fail_stop("Unable to write to shared archive file.");
543 }
544 }
545 _file_offset += nbytes;
546 }
547
548
549 // Align file position to an allocation unit boundary.
550
551 void FileMapInfo::align_file_position() {
552 size_t new_file_offset = align_up(_file_offset,
553 os::vm_allocation_granularity());
554 if (new_file_offset != _file_offset) {
555 _file_offset = new_file_offset;
556 if (_file_open) {
557 // Seek one byte back from the target and write a byte to insure
558 // that the written file is the correct length.
559 _file_offset -= 1;
560 if (lseek(_fd, (long)_file_offset, SEEK_SET) < 0) {
561 fail_stop("Unable to seek.");
562 }
563 char zero = 0;
564 write_bytes(&zero, 1);
565 }
566 }
567 }
568
569
570 // Dump bytes to file -- at the current file position.
571
572 void FileMapInfo::write_bytes_aligned(const void* buffer, int nbytes) {
573 align_file_position();
574 write_bytes(buffer, nbytes);
575 align_file_position();
576 }
577
578
579 // Close the shared archive file. This does NOT unmap mapped regions.
580
581 void FileMapInfo::close() {
582 if (_file_open) {
583 if (::close(_fd) < 0) {
584 fail_stop("Unable to close the shared archive file.");
585 }
586 _file_open = false;
587 _fd = -1;
588 }
589 }
590
591
592 // JVM/TI RedefineClasses() support:
593 // Remap the shared readonly space to shared readwrite, private.
594 bool FileMapInfo::remap_shared_readonly_as_readwrite() {
595 int idx = MetaspaceShared::ro;
596 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[idx];
597 if (!si->_read_only) {
598 // the space is already readwrite so we are done
599 return true;
600 }
601 size_t used = si->_used;
602 size_t size = align_up(used, os::vm_allocation_granularity());
603 if (!open_for_read()) {
604 return false;
605 }
606 char *addr = _header->region_addr(idx);
607 char *base = os::remap_memory(_fd, _full_path, si->_file_offset,
608 addr, size, false /* !read_only */,
609 si->_allow_exec);
610 close();
611 if (base == NULL) {
612 fail_continue("Unable to remap shared readonly space (errno=%d).", errno);
613 return false;
614 }
615 if (base != addr) {
616 fail_continue("Unable to remap shared readonly space at required address.");
617 return false;
618 }
619 si->_read_only = false;
620 return true;
621 }
622
623 // Map the whole region at once, assumed to be allocated contiguously.
624 ReservedSpace FileMapInfo::reserve_shared_memory() {
625 char* requested_addr = _header->region_addr(0);
626 size_t size = FileMapInfo::core_spaces_size();
627
628 // Reserve the space first, then map otherwise map will go right over some
629 // other reserved memory (like the code cache).
630 ReservedSpace rs(size, os::vm_allocation_granularity(), false, requested_addr);
631 if (!rs.is_reserved()) {
632 fail_continue("Unable to reserve shared space at required address "
633 INTPTR_FORMAT, p2i(requested_addr));
634 return rs;
635 }
636 // the reserved virtual memory is for mapping class data sharing archive
637 MemTracker::record_virtual_memory_type((address)rs.base(), mtClassShared);
638
639 return rs;
640 }
641
642 // Memory map a region in the address space.
643 static const char* shared_region_name[] = { "ReadOnly", "ReadWrite", "MiscData", "MiscCode",
644 "String1", "String2", "OptionalData" };
645
646 char* FileMapInfo::map_region(int i) {
647 assert(!MetaspaceShared::is_string_region(i), "sanity");
648 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
649 size_t used = si->_used;
650 size_t alignment = os::vm_allocation_granularity();
651 size_t size = align_up(used, alignment);
652 char *requested_addr = _header->region_addr(i);
653
654 // If a tool agent is in use (debugging enabled), we must map the address space RW
655 if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space()) {
656 si->_read_only = false;
657 }
658
659 // map the contents of the CDS archive in this memory
660 char *base = os::map_memory(_fd, _full_path, si->_file_offset,
661 requested_addr, size, si->_read_only,
662 si->_allow_exec);
663 if (base == NULL || base != requested_addr) {
664 fail_continue("Unable to map %s shared space at required address.", shared_region_name[i]);
665 return NULL;
666 }
667 #ifdef _WINDOWS
668 // This call is Windows-only because the memory_type gets recorded for the other platforms
669 // in method FileMapInfo::reserve_shared_memory(), which is not called on Windows.
670 MemTracker::record_virtual_memory_type((address)base, mtClassShared);
671 #endif
672
673 return base;
674 }
675
676 static MemRegion *string_ranges = NULL;
677 static int num_ranges = 0;
678 bool FileMapInfo::map_string_regions() {
679 #if INCLUDE_ALL_GCS
680 if (UseG1GC && UseCompressedOops && UseCompressedClassPointers) {
681 // Check that all the narrow oop and klass encodings match the archive
682 if (narrow_oop_mode() != Universe::narrow_oop_mode() ||
683 narrow_oop_shift() != Universe::narrow_oop_shift() ||
684 narrow_klass_base() != Universe::narrow_klass_base() ||
685 narrow_klass_shift() != Universe::narrow_klass_shift()) {
686 if (log_is_enabled(Info, cds) && _header->_space[MetaspaceShared::first_string]._used > 0) {
687 log_info(cds)("Shared string data from the CDS archive is being ignored. "
688 "The current CompressedOops/CompressedClassPointers encoding differs from "
689 "that archived due to heap size change. The archive was dumped using max heap "
690 "size " UINTX_FORMAT "M.", max_heap_size()/M);
691 }
692 } else {
693 string_ranges = new MemRegion[MetaspaceShared::max_strings];
694 struct FileMapInfo::FileMapHeader::space_info* si;
695
696 for (int i = MetaspaceShared::first_string;
697 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
698 si = &_header->_space[i];
699 size_t used = si->_used;
700 if (used > 0) {
701 size_t size = used;
702 char* requested_addr = (char*)((void*)oopDesc::decode_heap_oop_not_null(
703 (narrowOop)si->_addr._offset));
704 string_ranges[num_ranges] = MemRegion((HeapWord*)requested_addr, size / HeapWordSize);
705 num_ranges ++;
706 }
707 }
708
709 if (num_ranges == 0) {
710 StringTable::ignore_shared_strings(true);
711 return true; // no shared string data
712 }
713
714 // Check that ranges are within the java heap
715 if (!G1CollectedHeap::heap()->check_archive_addresses(string_ranges, num_ranges)) {
716 fail_continue("Unable to allocate shared string space: range is not "
717 "within java heap.");
718 return false;
719 }
720
721 // allocate from java heap
722 if (!G1CollectedHeap::heap()->alloc_archive_regions(string_ranges, num_ranges)) {
723 fail_continue("Unable to allocate shared string space: range is "
724 "already in use.");
725 return false;
726 }
727
728 // Map the string data. No need to call MemTracker::record_virtual_memory_type()
729 // for mapped string regions as they are part of the reserved java heap, which
730 // is already recorded.
731 for (int i = 0; i < num_ranges; i++) {
732 si = &_header->_space[MetaspaceShared::first_string + i];
733 char* addr = (char*)string_ranges[i].start();
734 char* base = os::map_memory(_fd, _full_path, si->_file_offset,
735 addr, string_ranges[i].byte_size(), si->_read_only,
736 si->_allow_exec);
737 if (base == NULL || base != addr) {
738 // dealloc the string regions from java heap
739 dealloc_string_regions();
740 fail_continue("Unable to map shared string space at required address.");
741 return false;
742 }
743 }
744
745 if (!verify_string_regions()) {
746 // dealloc the string regions from java heap
747 dealloc_string_regions();
748 fail_continue("Shared string regions are corrupt");
749 return false;
750 }
751
752 // the shared string data is mapped successfully
753 return true;
754 }
755 } else {
756 if (log_is_enabled(Info, cds) && _header->_space[MetaspaceShared::first_string]._used > 0) {
757 log_info(cds)("Shared string data from the CDS archive is being ignored. UseG1GC, "
758 "UseCompressedOops and UseCompressedClassPointers are required.");
759 }
760 }
761
762 // if we get here, the shared string data is not mapped
763 assert(string_ranges == NULL && num_ranges == 0, "sanity");
764 StringTable::ignore_shared_strings(true);
765 #endif
766 return true;
767 }
768
769 bool FileMapInfo::verify_string_regions() {
770 for (int i = MetaspaceShared::first_string;
771 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
772 if (!verify_region_checksum(i)) {
773 return false;
774 }
775 }
776 return true;
777 }
778
779 void FileMapInfo::fixup_string_regions() {
780 #if INCLUDE_ALL_GCS
781 // If any string regions were found, call the fill routine to make them parseable.
782 // Note that string_ranges may be non-NULL even if no ranges were found.
783 if (num_ranges != 0) {
784 assert(string_ranges != NULL, "Null string_ranges array with non-zero count");
785 G1CollectedHeap::heap()->fill_archive_regions(string_ranges, num_ranges);
786 }
787 #endif
788 }
789
790 bool FileMapInfo::verify_region_checksum(int i) {
791 if (!VerifySharedSpaces) {
792 return true;
793 }
794
795 size_t sz = _header->_space[i]._used;
796
797 if (sz == 0) {
798 return true; // no data
799 }
800 if (MetaspaceShared::is_string_region(i) && StringTable::shared_string_ignored()) {
801 return true; // shared string data are not mapped
802 }
803 const char* buf = _header->region_addr(i);
804 int crc = ClassLoader::crc32(0, buf, (jint)sz);
805 if (crc != _header->_space[i]._crc) {
806 fail_continue("Checksum verification failed.");
807 return false;
808 }
809 return true;
810 }
811
812 // Unmap a memory region in the address space.
813
814 void FileMapInfo::unmap_region(int i) {
815 assert(!MetaspaceShared::is_string_region(i), "sanity");
816 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
817 size_t used = si->_used;
818 size_t size = align_up(used, os::vm_allocation_granularity());
819
820 if (used == 0) {
821 return;
822 }
823
824 char* addr = _header->region_addr(i);
825 if (!os::unmap_memory(addr, size)) {
826 fail_stop("Unable to unmap shared space.");
827 }
828 }
829
830 // dealloc the archived string region from java heap
831 void FileMapInfo::dealloc_string_regions() {
832 #if INCLUDE_ALL_GCS
833 if (num_ranges > 0) {
834 assert(string_ranges != NULL, "Null string_ranges array with non-zero count");
835 G1CollectedHeap::heap()->dealloc_archive_regions(string_ranges, num_ranges);
836 }
837 #endif
838 }
839
840 void FileMapInfo::assert_mark(bool check) {
841 if (!check) {
842 fail_stop("Mark mismatch while restoring from shared file.");
843 }
844 }
845
846 void FileMapInfo::metaspace_pointers_do(MetaspaceClosure* it) {
847 it->push(&_classpath_entry_table);
848 for (int i=0; i<_classpath_entry_table_size; i++) {
849 shared_classpath(i)->metaspace_pointers_do(it);
850 }
851 }
852
853
854 FileMapInfo* FileMapInfo::_current_info = NULL;
855 Array<u8>* FileMapInfo::_classpath_entry_table = NULL;
856 int FileMapInfo::_classpath_entry_table_size = 0;
857 size_t FileMapInfo::_classpath_entry_size = 0x1234baad;
858 bool FileMapInfo::_validating_classpath_entry_table = false;
859
860 // Open the shared archive file, read and validate the header
861 // information (version, boot classpath, etc.). If initialization
862 // fails, shared spaces are disabled and the file is closed. [See
863 // fail_continue.]
864 //
865 // Validation of the archive is done in two steps:
866 //
867 // [1] validate_header() - done here. This checks the header, including _paths_misc_info.
868 // [2] validate_classpath_entry_table - this is done later, because the table is in the RW
869 // region of the archive, which is not mapped yet.
870 bool FileMapInfo::initialize() {
871 assert(UseSharedSpaces, "UseSharedSpaces expected.");
872
873 if (!open_for_read()) {
874 return false;
875 }
876
877 init_from_file(_fd);
878 if (!validate_header()) {
879 return false;
880 }
881 return true;
882 }
883
884 char* FileMapInfo::FileMapHeader::region_addr(int idx) {
885 if (MetaspaceShared::is_string_region(idx)) {
886 return (char*)((void*)oopDesc::decode_heap_oop_not_null(
887 (narrowOop)_space[idx]._addr._offset));
888 } else {
889 return _space[idx]._addr._base;
890 }
891 }
892
893 int FileMapInfo::FileMapHeader::compute_crc() {
894 char* header = data();
895 // start computing from the field after _crc
896 char* buf = (char*)&_crc + sizeof(int);
897 size_t sz = data_size() - (buf - header);
898 int crc = ClassLoader::crc32(0, buf, (jint)sz);
899 return crc;
900 }
901
902 bool FileMapInfo::FileMapHeader::validate() {
903 if (VerifySharedSpaces && compute_crc() != _crc) {
904 fail_continue("Header checksum verification failed.");
905 return false;
906 }
907
908 if (!Arguments::has_jimage()) {
909 FileMapInfo::fail_continue("The shared archive file cannot be used with an exploded module build.");
910 return false;
911 }
912
913 if (_version != current_version()) {
914 FileMapInfo::fail_continue("The shared archive file is the wrong version.");
915 return false;
916 }
917 if (_magic != (int)0xf00baba2) {
918 FileMapInfo::fail_continue("The shared archive file has a bad magic number.");
919 return false;
920 }
921 char header_version[JVM_IDENT_MAX];
922 get_header_version(header_version);
923 if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) {
924 log_info(class, path)("expected: %s", header_version);
925 log_info(class, path)("actual: %s", _jvm_ident);
926 FileMapInfo::fail_continue("The shared archive file was created by a different"
927 " version or build of HotSpot");
928 return false;
929 }
930 if (_obj_alignment != ObjectAlignmentInBytes) {
931 FileMapInfo::fail_continue("The shared archive file's ObjectAlignmentInBytes of %d"
932 " does not equal the current ObjectAlignmentInBytes of " INTX_FORMAT ".",
933 _obj_alignment, ObjectAlignmentInBytes);
934 return false;
935 }
936 if (_compact_strings != CompactStrings) {
937 FileMapInfo::fail_continue("The shared archive file's CompactStrings setting (%s)"
938 " does not equal the current CompactStrings setting (%s).",
939 _compact_strings ? "enabled" : "disabled",
940 CompactStrings ? "enabled" : "disabled");
941 return false;
942 }
943
944 return true;
945 }
946
947 bool FileMapInfo::validate_header() {
948 bool status = _header->validate();
949
950 if (status) {
951 if (!ClassLoader::check_shared_paths_misc_info(_paths_misc_info, _header->_paths_misc_info_size)) {
952 if (!PrintSharedArchiveAndExit) {
953 fail_continue("shared class paths mismatch (hint: enable -Xlog:class+path=info to diagnose the failure)");
954 status = false;
955 }
956 }
957 }
958
959 if (_paths_misc_info != NULL) {
960 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
961 _paths_misc_info = NULL;
962 }
963 return status;
964 }
965
966 // The following method is provided to see whether a given pointer
967 // falls in the mapped shared space.
968 // Param:
969 // p, The given pointer
970 // Return:
971 // True if the p is within the mapped shared space, otherwise, false.
972 bool FileMapInfo::is_in_shared_space(const void* p) {
973 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
974 char *base;
975 if (MetaspaceShared::is_string_region(i) && _header->_space[i]._used == 0) {
976 continue;
977 }
978 base = _header->region_addr(i);
979 if (p >= base && p < base + _header->_space[i]._used) {
980 return true;
981 }
982 }
983
984 return false;
985 }
986
987 // Check if a given address is within one of the shared regions ( ro, rw, mc or md)
988 bool FileMapInfo::is_in_shared_region(const void* p, int idx) {
989 assert(idx == MetaspaceShared::ro ||
990 idx == MetaspaceShared::rw ||
991 idx == MetaspaceShared::mc ||
992 idx == MetaspaceShared::md, "invalid region index");
993 char* base = _header->region_addr(idx);
994 if (p >= base && p < base + _header->_space[idx]._used) {
995 return true;
996 }
997 return false;
998 }
999
1000 void FileMapInfo::print_shared_spaces() {
1001 tty->print_cr("Shared Spaces:");
1002 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
1003 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
1004 char *base = _header->region_addr(i);
1005 tty->print(" %s " INTPTR_FORMAT "-" INTPTR_FORMAT,
1006 shared_region_name[i],
1007 p2i(base), p2i(base + si->_used));
1008 }
1009 }
1010
1011 // Unmap mapped regions of shared space.
1012 void FileMapInfo::stop_sharing_and_unmap(const char* msg) {
1013 FileMapInfo *map_info = FileMapInfo::current_info();
1014 if (map_info) {
1015 map_info->fail_continue("%s", msg);
1016 for (int i = 0; i < MetaspaceShared::num_non_strings; i++) {
1017 char *addr = map_info->_header->region_addr(i);
1018 if (addr != NULL && !MetaspaceShared::is_string_region(i)) {
1019 map_info->unmap_region(i);
1020 map_info->_header->_space[i]._addr._base = NULL;
1021 }
1022 }
1023 // Dealloc the string regions only without unmapping. The string regions are part
1024 // of the java heap. Unmapping of the heap regions are managed by GC.
1025 map_info->dealloc_string_regions();
1026 } else if (DumpSharedSpaces) {
1027 fail_stop("%s", msg);
1028 }
1029 }