1 /*
2 * Copyright (c) 2003, 2016, 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 "memory/filemap.hpp"
36 #include "memory/metadataFactory.hpp"
37 #include "memory/oopFactory.hpp"
38 #include "oops/objArrayOop.hpp"
39 #include "prims/jvmtiExport.hpp"
40 #include "runtime/arguments.hpp"
41 #include "runtime/java.hpp"
42 #include "runtime/os.hpp"
43 #include "runtime/vm_version.hpp"
44 #include "services/memTracker.hpp"
45 #include "utilities/defaultStream.hpp"
46
47 # include <sys/stat.h>
48 # include <errno.h>
49
50 #ifndef O_BINARY // if defined (Win32) use binary files.
51 #define O_BINARY 0 // otherwise do nothing.
52 #endif
53
54 extern address JVM_FunctionAtStart();
55 extern address JVM_FunctionAtEnd();
56
57 // Complain and stop. All error conditions occurring during the writing of
58 // an archive file should stop the process. Unrecoverable errors during
59 // the reading of the archive file should stop the process.
60
61 static void fail(const char *msg, va_list ap) {
62 // This occurs very early during initialization: tty is not initialized.
63 jio_fprintf(defaultStream::error_stream(),
64 "An error has occurred while processing the"
65 " shared archive file.\n");
66 jio_vfprintf(defaultStream::error_stream(), msg, ap);
67 jio_fprintf(defaultStream::error_stream(), "\n");
68 // Do not change the text of the below message because some tests check for it.
69 vm_exit_during_initialization("Unable to use shared archive.", NULL);
70 }
71
72
73 void FileMapInfo::fail_stop(const char *msg, ...) {
74 va_list ap;
75 va_start(ap, msg);
76 fail(msg, ap); // Never returns.
77 va_end(ap); // for completeness.
78 }
79
80
81 // Complain and continue. Recoverable errors during the reading of the
82 // archive file may continue (with sharing disabled).
83 //
84 // If we continue, then disable shared spaces and close the file.
85
86 void FileMapInfo::fail_continue(const char *msg, ...) {
87 va_list ap;
88 va_start(ap, msg);
89 MetaspaceShared::set_archive_loading_failed();
90 if (PrintSharedArchiveAndExit && _validating_classpath_entry_table) {
91 // If we are doing PrintSharedArchiveAndExit and some of the classpath entries
92 // do not validate, we can still continue "limping" to validate the remaining
93 // entries. No need to quit.
94 tty->print("[");
95 tty->vprint(msg, ap);
96 tty->print_cr("]");
97 } else {
98 if (RequireSharedSpaces) {
99 fail(msg, ap);
100 } else {
101 if (PrintSharedSpaces) {
102 tty->print("UseSharedSpaces: ");
103 tty->vprint_cr(msg, ap);
104 }
105 }
106 UseSharedSpaces = false;
107 assert(current_info() != NULL, "singleton must be registered");
108 current_info()->close();
109 }
110 va_end(ap);
111 }
112
113 // Fill in the fileMapInfo structure with data about this VM instance.
114
115 // This method copies the vm version info into header_version. If the version is too
116 // long then a truncated version, which has a hash code appended to it, is copied.
117 //
118 // Using a template enables this method to verify that header_version is an array of
119 // length JVM_IDENT_MAX. This ensures that the code that writes to the CDS file and
120 // the code that reads the CDS file will both use the same size buffer. Hence, will
121 // use identical truncation. This is necessary for matching of truncated versions.
122 template <int N> static void get_header_version(char (&header_version) [N]) {
123 assert(N == JVM_IDENT_MAX, "Bad header_version size");
124
125 const char *vm_version = VM_Version::internal_vm_info_string();
126 const int version_len = (int)strlen(vm_version);
127
128 if (version_len < (JVM_IDENT_MAX-1)) {
129 strcpy(header_version, vm_version);
130
131 } else {
132 // Get the hash value. Use a static seed because the hash needs to return the same
133 // value over multiple jvm invocations.
134 unsigned int hash = AltHashing::murmur3_32(8191, (const jbyte*)vm_version, version_len);
135
136 // Truncate the ident, saving room for the 8 hex character hash value.
137 strncpy(header_version, vm_version, JVM_IDENT_MAX-9);
138
139 // Append the hash code as eight hex digits.
140 sprintf(&header_version[JVM_IDENT_MAX-9], "%08x", hash);
141 header_version[JVM_IDENT_MAX-1] = 0; // Null terminate.
142 }
143 }
144
145 FileMapInfo::FileMapInfo() {
146 assert(_current_info == NULL, "must be singleton"); // not thread safe
147 _current_info = this;
148 memset(this, 0, sizeof(FileMapInfo));
149 _file_offset = 0;
150 _file_open = false;
151 _header = SharedClassUtil::allocate_file_map_header();
152 _header->_version = _invalid_version;
153 }
154
155 FileMapInfo::~FileMapInfo() {
156 assert(_current_info == this, "must be singleton"); // not thread safe
157 _current_info = NULL;
158 }
159
160 void FileMapInfo::populate_header(size_t alignment) {
161 _header->populate(this, alignment);
162 }
163
164 size_t FileMapInfo::FileMapHeader::data_size() {
165 return SharedClassUtil::file_map_header_size() - sizeof(FileMapInfo::FileMapHeaderBase);
166 }
167
168 void FileMapInfo::FileMapHeader::populate(FileMapInfo* mapinfo, size_t alignment) {
169 _magic = 0xf00baba2;
170 _version = _current_version;
171 _alignment = alignment;
172 _obj_alignment = ObjectAlignmentInBytes;
173 _compact_strings = CompactStrings;
174 _narrow_oop_mode = Universe::narrow_oop_mode();
175 _narrow_oop_shift = Universe::narrow_oop_shift();
176 _max_heap_size = MaxHeapSize;
177 _narrow_klass_base = Universe::narrow_klass_base();
178 _narrow_klass_shift = Universe::narrow_klass_shift();
179 _classpath_entry_table_size = mapinfo->_classpath_entry_table_size;
180 _classpath_entry_table = mapinfo->_classpath_entry_table;
181 _classpath_entry_size = mapinfo->_classpath_entry_size;
182
183 // The following fields are for sanity checks for whether this archive
184 // will function correctly with this JVM and the bootclasspath it's
185 // invoked with.
186
187 // JVM version string ... changes on each build.
188 get_header_version(_jvm_ident);
189 }
190
191 void FileMapInfo::allocate_classpath_entry_table() {
192 int bytes = 0;
193 int count = 0;
194 char* strptr = NULL;
195 char* strptr_max = NULL;
196 Thread* THREAD = Thread::current();
197
198 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
199 size_t entry_size = SharedClassUtil::shared_class_path_entry_size();
200
201 for (int pass=0; pass<2; pass++) {
202 ClassPathEntry *cpe = ClassLoader::classpath_entry(0);
203
204 for (int cur_entry = 0 ; cpe != NULL; cpe = cpe->next(), cur_entry++) {
205 const char *name = cpe->name();
206 int name_bytes = (int)(strlen(name) + 1);
207
208 if (pass == 0) {
209 count ++;
210 bytes += (int)entry_size;
211 bytes += name_bytes;
212 log_info(class, path)("add main shared path (%s) %s", (cpe->is_jar_file() ? "jar" : "dir"), name);
213 } else {
214 SharedClassPathEntry* ent = shared_classpath(cur_entry);
215 if (cpe->is_jar_file()) {
216 struct stat st;
217 if (os::stat(name, &st) != 0) {
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 jar file %s.", name);
224 }
225
226 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error.
227 SharedClassUtil::update_shared_classpath(cpe, ent, st.st_mtime, st.st_size, THREAD);
228 } else {
229 struct stat st;
230 if (os::stat(name, &st) == 0) {
231 if (cpe->is_jrt()) {
232 // it's the "modules" jimage
233 ent->_timestamp = st.st_mtime;
234 ent->_filesize = st.st_size;
235 } else if ((st.st_mode & S_IFDIR) == S_IFDIR) {
236 if (!os::dir_is_empty(name)) {
237 ClassLoader::exit_with_path_failure(
238 "Cannot have non-empty directory in archived classpaths", name);
239 }
240 ent->_filesize = -1;
241 }
242 }
243 if (ent->_filesize == 0) {
244 // unknown
245 ent->_filesize = -2;
246 }
247 }
248 ent->_name = strptr;
249 if (strptr + name_bytes <= strptr_max) {
250 strncpy(strptr, name, (size_t)name_bytes); // name_bytes includes trailing 0.
251 strptr += name_bytes;
252 } else {
253 assert(0, "miscalculated buffer size");
254 }
255 }
256 }
257
258 if (pass == 0) {
259 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error.
260 Array<u8>* arr = MetadataFactory::new_array<u8>(loader_data, (bytes + 7)/8, THREAD);
261 strptr = (char*)(arr->data());
262 strptr_max = strptr + bytes;
263 SharedClassPathEntry* table = (SharedClassPathEntry*)strptr;
264 strptr += entry_size * count;
265
266 _classpath_entry_table_size = count;
267 _classpath_entry_table = table;
268 _classpath_entry_size = entry_size;
269 }
270 }
271 }
272
273 bool FileMapInfo::validate_classpath_entry_table() {
274 _validating_classpath_entry_table = true;
275
276 int count = _header->_classpath_entry_table_size;
277
278 _classpath_entry_table = _header->_classpath_entry_table;
279 _classpath_entry_size = _header->_classpath_entry_size;
280
281 for (int i=0; i<count; i++) {
282 SharedClassPathEntry* ent = shared_classpath(i);
283 struct stat st;
284 const char* name = ent->_name;
285 bool ok = true;
286 log_info(class, path)("checking shared classpath entry: %s", name);
287 if (os::stat(name, &st) != 0) {
288 fail_continue("Required classpath entry does not exist: %s", name);
289 ok = false;
290 } else if (ent->is_dir()) {
291 if (!os::dir_is_empty(name)) {
292 fail_continue("directory is not empty: %s", name);
293 ok = false;
294 }
295 } else if (ent->is_jar_or_bootimage()) {
296 if (ent->_timestamp != st.st_mtime ||
297 ent->_filesize != st.st_size) {
298 ok = false;
299 if (PrintSharedArchiveAndExit) {
300 fail_continue(ent->_timestamp != st.st_mtime ?
301 "Timestamp mismatch" :
302 "File size mismatch");
303 } else {
304 fail_continue("A jar/jimage file is not the one used while building"
305 " the shared archive file: %s", name);
306 }
307 }
308 }
309 if (ok) {
310 log_info(class, path)("ok");
311 } else if (!PrintSharedArchiveAndExit) {
312 _validating_classpath_entry_table = false;
313 return false;
314 }
315 }
316
317 _classpath_entry_table_size = _header->_classpath_entry_table_size;
318 _validating_classpath_entry_table = false;
319 return true;
320 }
321
322
323 // Read the FileMapInfo information from the file.
324
325 bool FileMapInfo::init_from_file(int fd) {
326 size_t sz = _header->data_size();
327 char* addr = _header->data();
328 size_t n = os::read(fd, addr, (unsigned int)sz);
329 if (n != sz) {
330 fail_continue("Unable to read the file header.");
331 return false;
332 }
333 if (_header->_version != current_version()) {
334 fail_continue("The shared archive file has the wrong version.");
335 return false;
336 }
337 _file_offset = (long)n;
338
339 size_t info_size = _header->_paths_misc_info_size;
340 _paths_misc_info = NEW_C_HEAP_ARRAY_RETURN_NULL(char, info_size, mtClass);
341 if (_paths_misc_info == NULL) {
342 fail_continue("Unable to read the file header.");
343 return false;
344 }
345 n = os::read(fd, _paths_misc_info, (unsigned int)info_size);
346 if (n != info_size) {
347 fail_continue("Unable to read the shared path info header.");
348 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
349 _paths_misc_info = NULL;
350 return false;
351 }
352
353 size_t len = lseek(fd, 0, SEEK_END);
354 struct FileMapInfo::FileMapHeader::space_info* si =
355 &_header->_space[MetaspaceShared::mc];
356 if (si->_file_offset >= len || len - si->_file_offset < si->_used) {
357 fail_continue("The shared archive file has been truncated.");
358 return false;
359 }
360
361 _file_offset += (long)n;
362 return true;
363 }
364
365
366 // Read the FileMapInfo information from the file.
367 bool FileMapInfo::open_for_read() {
368 _full_path = Arguments::GetSharedArchivePath();
369 int fd = open(_full_path, O_RDONLY | O_BINARY, 0);
370 if (fd < 0) {
371 if (errno == ENOENT) {
372 // Not locating the shared archive is ok.
373 fail_continue("Specified shared archive not found.");
374 } else {
375 fail_continue("Failed to open shared archive file (%s).",
376 os::strerror(errno));
377 }
378 return false;
379 }
380
381 _fd = fd;
382 _file_open = true;
383 return true;
384 }
385
386
387 // Write the FileMapInfo information to the file.
388
389 void FileMapInfo::open_for_write() {
390 _full_path = Arguments::GetSharedArchivePath();
391 if (PrintSharedSpaces) {
392 tty->print_cr("Dumping shared data to file: ");
393 tty->print_cr(" %s", _full_path);
394 }
395
396 #ifdef _WINDOWS // On Windows, need WRITE permission to remove the file.
397 chmod(_full_path, _S_IREAD | _S_IWRITE);
398 #endif
399
400 // Use remove() to delete the existing file because, on Unix, this will
401 // allow processes that have it open continued access to the file.
402 remove(_full_path);
403 int fd = open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444);
404 if (fd < 0) {
405 fail_stop("Unable to create shared archive file %s: (%s).", _full_path,
406 os::strerror(errno));
407 }
408 _fd = fd;
409 _file_offset = 0;
410 _file_open = true;
411 }
412
413
414 // Write the header to the file, seek to the next allocation boundary.
415
416 void FileMapInfo::write_header() {
417 int info_size = ClassLoader::get_shared_paths_misc_info_size();
418
419 _header->_paths_misc_info_size = info_size;
420
421 align_file_position();
422 size_t sz = _header->data_size();
423 char* addr = _header->data();
424 write_bytes(addr, (int)sz); // skip the C++ vtable
425 write_bytes(ClassLoader::get_shared_paths_misc_info(), info_size);
426 align_file_position();
427 }
428
429
430 // Dump shared spaces to file.
431
432 void FileMapInfo::write_space(int i, Metaspace* space, bool read_only) {
433 align_file_position();
434 size_t used = space->used_bytes_slow(Metaspace::NonClassType);
435 size_t capacity = space->capacity_bytes_slow(Metaspace::NonClassType);
436 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
437 write_region(i, (char*)space->bottom(), used, capacity, read_only, false);
438 }
439
440
441 // Dump region to file.
442
443 void FileMapInfo::write_region(int region, char* base, size_t size,
444 size_t capacity, bool read_only,
445 bool allow_exec) {
446 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[region];
447
448 if (_file_open) {
449 guarantee(si->_file_offset == _file_offset, "file offset mismatch.");
450 if (PrintSharedSpaces) {
451 tty->print_cr("Shared file region %d: " SIZE_FORMAT_HEX_W(6) " bytes, addr " INTPTR_FORMAT
452 " file offset " SIZE_FORMAT_HEX_W(6), region, size, p2i(base), _file_offset);
453 }
454 } else {
455 si->_file_offset = _file_offset;
456 }
457 if (MetaspaceShared::is_string_region(region)) {
458 assert((base - (char*)Universe::narrow_oop_base()) % HeapWordSize == 0, "Sanity");
459 if (base != NULL) {
460 si->_addr._offset = (intx)oopDesc::encode_heap_oop_not_null((oop)base);
461 } else {
462 si->_addr._offset = 0;
463 }
464 } else {
465 si->_addr._base = base;
466 }
467 si->_used = size;
468 si->_capacity = capacity;
469 si->_read_only = read_only;
470 si->_allow_exec = allow_exec;
471 si->_crc = ClassLoader::crc32(0, base, (jint)size);
472 write_bytes_aligned(base, (int)size);
473 }
474
475 // Write the string space. The string space contains one or multiple GC(G1) regions.
476 // When the total string space size is smaller than one GC region of the dump time,
477 // only one string region is used for shared strings.
478 //
479 // If the total string space size is bigger than one GC region, there would be more
480 // than one GC regions allocated for shared strings. The first/bottom GC region might
481 // be a partial GC region with the empty portion at the higher address within that region.
482 // The non-empty portion of the first region is written into the archive as one string
483 // region. The rest are consecutive full GC regions if they exist, which can be written
484 // out in one chunk as another string region.
485 void FileMapInfo::write_string_regions(GrowableArray<MemRegion> *regions) {
486 for (int i = MetaspaceShared::first_string;
487 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
488 char* start = NULL;
489 size_t size = 0;
490 if (regions->is_nonempty()) {
491 if (i == MetaspaceShared::first_string) {
492 MemRegion first = regions->first();
493 start = (char*)first.start();
494 size = first.byte_size();
495 } else {
496 int len = regions->length();
497 if (len > 1) {
498 start = (char*)regions->at(1).start();
499 size = (char*)regions->at(len - 1).end() - start;
500 }
501 }
502 }
503 write_region(i, start, size, size, false, false);
504 }
505 }
506
507
508 // Dump bytes to file -- at the current file position.
509
510 void FileMapInfo::write_bytes(const void* buffer, int nbytes) {
511 if (_file_open) {
512 int n = ::write(_fd, buffer, nbytes);
513 if (n != nbytes) {
514 // It is dangerous to leave the corrupted shared archive file around,
515 // close and remove the file. See bug 6372906.
516 close();
517 remove(_full_path);
518 fail_stop("Unable to write to shared archive file.");
519 }
520 }
521 _file_offset += nbytes;
522 }
523
524
525 // Align file position to an allocation unit boundary.
526
527 void FileMapInfo::align_file_position() {
528 size_t new_file_offset = align_size_up(_file_offset,
529 os::vm_allocation_granularity());
530 if (new_file_offset != _file_offset) {
531 _file_offset = new_file_offset;
532 if (_file_open) {
533 // Seek one byte back from the target and write a byte to insure
534 // that the written file is the correct length.
535 _file_offset -= 1;
536 if (lseek(_fd, (long)_file_offset, SEEK_SET) < 0) {
537 fail_stop("Unable to seek.");
538 }
539 char zero = 0;
540 write_bytes(&zero, 1);
541 }
542 }
543 }
544
545
546 // Dump bytes to file -- at the current file position.
547
548 void FileMapInfo::write_bytes_aligned(const void* buffer, int nbytes) {
549 align_file_position();
550 write_bytes(buffer, nbytes);
551 align_file_position();
552 }
553
554
555 // Close the shared archive file. This does NOT unmap mapped regions.
556
557 void FileMapInfo::close() {
558 if (_file_open) {
559 if (::close(_fd) < 0) {
560 fail_stop("Unable to close the shared archive file.");
561 }
562 _file_open = false;
563 _fd = -1;
564 }
565 }
566
567
568 // JVM/TI RedefineClasses() support:
569 // Remap the shared readonly space to shared readwrite, private.
570 bool FileMapInfo::remap_shared_readonly_as_readwrite() {
571 int idx = 0;
572 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[idx];
573 if (!si->_read_only) {
574 // the space is already readwrite so we are done
575 return true;
576 }
577 size_t used = si->_used;
578 size_t size = align_size_up(used, os::vm_allocation_granularity());
579 if (!open_for_read()) {
580 return false;
581 }
582 char *addr = _header->region_addr(idx);
583 char *base = os::remap_memory(_fd, _full_path, si->_file_offset,
584 addr, size, false /* !read_only */,
585 si->_allow_exec);
586 close();
587 if (base == NULL) {
588 fail_continue("Unable to remap shared readonly space (errno=%d).", errno);
589 return false;
590 }
591 if (base != addr) {
592 fail_continue("Unable to remap shared readonly space at required address.");
593 return false;
594 }
595 si->_read_only = false;
596 return true;
597 }
598
599 // Map the whole region at once, assumed to be allocated contiguously.
600 ReservedSpace FileMapInfo::reserve_shared_memory() {
601 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[0];
602 char* requested_addr = _header->region_addr(0);
603
604 size_t size = FileMapInfo::shared_spaces_size();
605
606 // Reserve the space first, then map otherwise map will go right over some
607 // other reserved memory (like the code cache).
608 ReservedSpace rs(size, os::vm_allocation_granularity(), false, requested_addr);
609 if (!rs.is_reserved()) {
610 fail_continue("Unable to reserve shared space at required address "
611 INTPTR_FORMAT, p2i(requested_addr));
612 return rs;
613 }
614 // the reserved virtual memory is for mapping class data sharing archive
615 MemTracker::record_virtual_memory_type((address)rs.base(), mtClassShared);
616
617 return rs;
618 }
619
620 // Memory map a region in the address space.
621 static const char* shared_region_name[] = { "ReadOnly", "ReadWrite", "MiscData", "MiscCode",
622 "String1", "String2" };
623
624 char* FileMapInfo::map_region(int i) {
625 assert(!MetaspaceShared::is_string_region(i), "sanity");
626 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
627 size_t used = si->_used;
628 size_t alignment = os::vm_allocation_granularity();
629 size_t size = align_size_up(used, alignment);
630 char *requested_addr = _header->region_addr(i);
631
632 // If a tool agent is in use (debugging enabled), we must map the address space RW
633 if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space()) {
634 si->_read_only = false;
635 }
636
637 // map the contents of the CDS archive in this memory
638 char *base = os::map_memory(_fd, _full_path, si->_file_offset,
639 requested_addr, size, si->_read_only,
640 si->_allow_exec);
641 if (base == NULL || base != requested_addr) {
642 fail_continue("Unable to map %s shared space at required address.", shared_region_name[i]);
643 return NULL;
644 }
645 #ifdef _WINDOWS
646 // This call is Windows-only because the memory_type gets recorded for the other platforms
647 // in method FileMapInfo::reserve_shared_memory(), which is not called on Windows.
648 MemTracker::record_virtual_memory_type((address)base, mtClassShared);
649 #endif
650
651 return base;
652 }
653
654 static MemRegion *string_ranges = NULL;
655 static int num_ranges = 0;
656 bool FileMapInfo::map_string_regions() {
657 #if INCLUDE_ALL_GCS
658 if (UseG1GC && UseCompressedOops && UseCompressedClassPointers) {
659 // Check that all the narrow oop and klass encodings match the archive
660 if (narrow_oop_mode() != Universe::narrow_oop_mode() ||
661 narrow_oop_shift() != Universe::narrow_oop_shift() ||
662 narrow_klass_base() != Universe::narrow_klass_base() ||
663 narrow_klass_shift() != Universe::narrow_klass_shift()) {
664 if (PrintSharedSpaces && _header->_space[MetaspaceShared::first_string]._used > 0) {
665 tty->print_cr("Shared string data from the CDS archive is being ignored. "
666 "The current CompressedOops/CompressedClassPointers encoding differs from "
667 "that archived due to heap size change. The archive was dumped using max heap "
668 "size " UINTX_FORMAT "M.", max_heap_size()/M);
669 }
670 } else {
671 string_ranges = new MemRegion[MetaspaceShared::max_strings];
672 struct FileMapInfo::FileMapHeader::space_info* si;
673
674 for (int i = MetaspaceShared::first_string;
675 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
676 si = &_header->_space[i];
677 size_t used = si->_used;
678 if (used > 0) {
679 size_t size = used;
680 char* requested_addr = (char*)((void*)oopDesc::decode_heap_oop_not_null(
681 (narrowOop)si->_addr._offset));
682 string_ranges[num_ranges] = MemRegion((HeapWord*)requested_addr, size / HeapWordSize);
683 num_ranges ++;
684 }
685 }
686
687 if (num_ranges == 0) {
688 StringTable::ignore_shared_strings(true);
689 return true; // no shared string data
690 }
691
692 // Check that ranges are within the java heap
693 if (!G1CollectedHeap::heap()->check_archive_addresses(string_ranges, num_ranges)) {
694 fail_continue("Unable to allocate shared string space: range is not "
695 "within java heap.");
696 return false;
697 }
698
699 // allocate from java heap
700 if (!G1CollectedHeap::heap()->alloc_archive_regions(string_ranges, num_ranges)) {
701 fail_continue("Unable to allocate shared string space: range is "
702 "already in use.");
703 return false;
704 }
705
706 // Map the string data. No need to call MemTracker::record_virtual_memory_type()
707 // for mapped string regions as they are part of the reserved java heap, which
708 // is already recorded.
709 for (int i = 0; i < num_ranges; i++) {
710 si = &_header->_space[MetaspaceShared::first_string + i];
711 char* addr = (char*)string_ranges[i].start();
712 char* base = os::map_memory(_fd, _full_path, si->_file_offset,
713 addr, string_ranges[i].byte_size(), si->_read_only,
714 si->_allow_exec);
715 if (base == NULL || base != addr) {
716 // dealloc the string regions from java heap
717 dealloc_string_regions();
718 fail_continue("Unable to map shared string space at required address.");
719 return false;
720 }
721 }
722
723 if (!verify_string_regions()) {
724 // dealloc the string regions from java heap
725 dealloc_string_regions();
726 fail_continue("Shared string regions are corrupt");
727 return false;
728 }
729
730 // the shared string data is mapped successfully
731 return true;
732 }
733 } else {
734 if (PrintSharedSpaces && _header->_space[MetaspaceShared::first_string]._used > 0) {
735 tty->print_cr("Shared string data from the CDS archive is being ignored. UseG1GC, "
736 "UseCompressedOops and UseCompressedClassPointers are required.");
737 }
738 }
739
740 // if we get here, the shared string data is not mapped
741 assert(string_ranges == NULL && num_ranges == 0, "sanity");
742 StringTable::ignore_shared_strings(true);
743 #endif
744 return true;
745 }
746
747 bool FileMapInfo::verify_string_regions() {
748 for (int i = MetaspaceShared::first_string;
749 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
750 if (!verify_region_checksum(i)) {
751 return false;
752 }
753 }
754 return true;
755 }
756
757 void FileMapInfo::fixup_string_regions() {
758 #if INCLUDE_ALL_GCS
759 // If any string regions were found, call the fill routine to make them parseable.
760 // Note that string_ranges may be non-NULL even if no ranges were found.
761 if (num_ranges != 0) {
762 assert(string_ranges != NULL, "Null string_ranges array with non-zero count");
763 G1CollectedHeap::heap()->fill_archive_regions(string_ranges, num_ranges);
764 }
765 #endif
766 }
767
768 bool FileMapInfo::verify_region_checksum(int i) {
769 if (!VerifySharedSpaces) {
770 return true;
771 }
772
773 size_t sz = _header->_space[i]._used;
774
775 if (sz == 0) {
776 return true; // no data
777 }
778 if (MetaspaceShared::is_string_region(i) && StringTable::shared_string_ignored()) {
779 return true; // shared string data are not mapped
780 }
781 const char* buf = _header->region_addr(i);
782 int crc = ClassLoader::crc32(0, buf, (jint)sz);
783 if (crc != _header->_space[i]._crc) {
784 fail_continue("Checksum verification failed.");
785 return false;
786 }
787 return true;
788 }
789
790 // Unmap a memory region in the address space.
791
792 void FileMapInfo::unmap_region(int i) {
793 assert(!MetaspaceShared::is_string_region(i), "sanity");
794 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
795 size_t used = si->_used;
796 size_t size = align_size_up(used, os::vm_allocation_granularity());
797
798 if (used == 0) {
799 return;
800 }
801
802 char* addr = _header->region_addr(i);
803 if (!os::unmap_memory(addr, size)) {
804 fail_stop("Unable to unmap shared space.");
805 }
806 }
807
808 // dealloc the archived string region from java heap
809 void FileMapInfo::dealloc_string_regions() {
810 #if INCLUDE_ALL_GCS
811 if (num_ranges > 0) {
812 assert(string_ranges != NULL, "Null string_ranges array with non-zero count");
813 G1CollectedHeap::heap()->dealloc_archive_regions(string_ranges, num_ranges);
814 }
815 #endif
816 }
817
818 void FileMapInfo::assert_mark(bool check) {
819 if (!check) {
820 fail_stop("Mark mismatch while restoring from shared file.");
821 }
822 }
823
824
825 FileMapInfo* FileMapInfo::_current_info = NULL;
826 SharedClassPathEntry* FileMapInfo::_classpath_entry_table = NULL;
827 int FileMapInfo::_classpath_entry_table_size = 0;
828 size_t FileMapInfo::_classpath_entry_size = 0x1234baad;
829 bool FileMapInfo::_validating_classpath_entry_table = false;
830
831 // Open the shared archive file, read and validate the header
832 // information (version, boot classpath, etc.). If initialization
833 // fails, shared spaces are disabled and the file is closed. [See
834 // fail_continue.]
835 //
836 // Validation of the archive is done in two steps:
837 //
838 // [1] validate_header() - done here. This checks the header, including _paths_misc_info.
839 // [2] validate_classpath_entry_table - this is done later, because the table is in the RW
840 // region of the archive, which is not mapped yet.
841 bool FileMapInfo::initialize() {
842 assert(UseSharedSpaces, "UseSharedSpaces expected.");
843
844 if (!open_for_read()) {
845 return false;
846 }
847
848 init_from_file(_fd);
849 if (!validate_header()) {
850 return false;
851 }
852
853 SharedReadOnlySize = _header->_space[0]._capacity;
854 SharedReadWriteSize = _header->_space[1]._capacity;
855 SharedMiscDataSize = _header->_space[2]._capacity;
856 SharedMiscCodeSize = _header->_space[3]._capacity;
857 return true;
858 }
859
860 char* FileMapInfo::FileMapHeader::region_addr(int idx) {
861 if (MetaspaceShared::is_string_region(idx)) {
862 return (char*)((void*)oopDesc::decode_heap_oop_not_null(
863 (narrowOop)_space[idx]._addr._offset));
864 } else {
865 return _space[idx]._addr._base;
866 }
867 }
868
869 int FileMapInfo::FileMapHeader::compute_crc() {
870 char* header = data();
871 // start computing from the field after _crc
872 char* buf = (char*)&_crc + sizeof(int);
873 size_t sz = data_size() - (buf - header);
874 int crc = ClassLoader::crc32(0, buf, (jint)sz);
875 return crc;
876 }
877
878 bool FileMapInfo::FileMapHeader::validate() {
879 if (VerifySharedSpaces && compute_crc() != _crc) {
880 fail_continue("Header checksum verification failed.");
881 return false;
882 }
883
884 if (Arguments::get_xpatchprefix() != NULL) {
885 FileMapInfo::fail_continue("The shared archive file cannot be used with -Xpatch.");
886 return false;
887 }
888
889 if (_version != current_version()) {
890 FileMapInfo::fail_continue("The shared archive file is the wrong version.");
891 return false;
892 }
893 if (_magic != (int)0xf00baba2) {
894 FileMapInfo::fail_continue("The shared archive file has a bad magic number.");
895 return false;
896 }
897 char header_version[JVM_IDENT_MAX];
898 get_header_version(header_version);
899 if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) {
900 log_info(class, path)("expected: %s", header_version);
901 log_info(class, path)("actual: %s", _jvm_ident);
902 FileMapInfo::fail_continue("The shared archive file was created by a different"
903 " version or build of HotSpot");
904 return false;
905 }
906 if (_obj_alignment != ObjectAlignmentInBytes) {
907 FileMapInfo::fail_continue("The shared archive file's ObjectAlignmentInBytes of %d"
908 " does not equal the current ObjectAlignmentInBytes of " INTX_FORMAT ".",
909 _obj_alignment, ObjectAlignmentInBytes);
910 return false;
911 }
912 if (_compact_strings != CompactStrings) {
913 FileMapInfo::fail_continue("The shared archive file's CompactStrings setting (%s)"
914 " does not equal the current CompactStrings setting (%s).",
915 _compact_strings ? "enabled" : "disabled",
916 CompactStrings ? "enabled" : "disabled");
917 return false;
918 }
919
920 return true;
921 }
922
923 bool FileMapInfo::validate_header() {
924 bool status = _header->validate();
925
926 if (status) {
927 if (!ClassLoader::check_shared_paths_misc_info(_paths_misc_info, _header->_paths_misc_info_size)) {
928 if (!PrintSharedArchiveAndExit) {
929 fail_continue("shared class paths mismatch (hint: enable -Xlog:class+path=info to diagnose the failure)");
930 status = false;
931 }
932 }
933 }
934
935 if (_paths_misc_info != NULL) {
936 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
937 _paths_misc_info = NULL;
938 }
939 return status;
940 }
941
942 // The following method is provided to see whether a given pointer
943 // falls in the mapped shared space.
944 // Param:
945 // p, The given pointer
946 // Return:
947 // True if the p is within the mapped shared space, otherwise, false.
948 bool FileMapInfo::is_in_shared_space(const void* p) {
949 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
950 char *base;
951 if (MetaspaceShared::is_string_region(i) && _header->_space[i]._used == 0) {
952 continue;
953 }
954 base = _header->region_addr(i);
955 if (p >= base && p < base + _header->_space[i]._used) {
956 return true;
957 }
958 }
959
960 return false;
961 }
962
963 // Check if a given address is within one of the shared regions (ro, rw, md, mc)
964 bool FileMapInfo::is_in_shared_region(const void* p, int idx) {
965 assert((idx >= MetaspaceShared::ro) && (idx <= MetaspaceShared::mc), "invalid region index");
966 char* base = _header->region_addr(idx);
967 if (p >= base && p < base + _header->_space[idx]._used) {
968 return true;
969 }
970 return false;
971 }
972
973 void FileMapInfo::print_shared_spaces() {
974 tty->print_cr("Shared Spaces:");
975 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
976 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
977 char *base = _header->region_addr(i);
978 tty->print(" %s " INTPTR_FORMAT "-" INTPTR_FORMAT,
979 shared_region_name[i],
980 p2i(base), p2i(base + si->_used));
981 }
982 }
983
984 // Unmap mapped regions of shared space.
985 void FileMapInfo::stop_sharing_and_unmap(const char* msg) {
986 FileMapInfo *map_info = FileMapInfo::current_info();
987 if (map_info) {
988 map_info->fail_continue("%s", msg);
989 for (int i = 0; i < MetaspaceShared::num_non_strings; i++) {
990 char *addr = map_info->_header->region_addr(i);
991 if (addr != NULL && !MetaspaceShared::is_string_region(i)) {
992 map_info->unmap_region(i);
993 map_info->_header->_space[i]._addr._base = NULL;
994 }
995 }
996 // Dealloc the string regions only without unmapping. The string regions are part
997 // of the java heap. Unmapping of the heap regions are managed by GC.
998 map_info->dealloc_string_regions();
999 } else if (DumpSharedSpaces) {
1000 fail_stop("%s", msg);
1001 }
1002 }