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
203 // Process the modular java runtime image first
204 ClassPathEntry* jrt_entry = ClassLoader::get_jrt_entry();
205 assert(jrt_entry != NULL,
206 "No modular java runtime image present when allocating the CDS classpath entry table");
207 const char *name = jrt_entry->name();
208 int name_bytes = (int)(strlen(name) + 1);
209 if (pass == 0) {
210 count++;
211 bytes += (int)entry_size;
212 bytes += name_bytes;
213 log_info(class, path)("add main shared path for modular java runtime image %s", name);
214 } else {
215 // The java runtime image is always in slot 0 on the shared class path.
216 SharedClassPathEntry* ent = shared_classpath(0);
217 struct stat st;
218 if (os::stat(name, &st) == 0) {
219 ent->_timestamp = st.st_mtime;
220 ent->_filesize = st.st_size;
221 }
222 if (ent->_filesize == 0) {
223 // unknown
224 ent->_filesize = -2;
225 }
226 ent->_name = strptr;
227 assert(strptr + name_bytes <= strptr_max, "miscalculated buffer size");
228 strncpy(strptr, name, (size_t)name_bytes); // name_bytes includes trailing 0.
229 strptr += name_bytes;
230 }
231
232 // Walk the appended entries, which includes the entries added for the classpath.
233 ClassPathEntry *cpe = ClassLoader::classpath_entry(1);
234
235 // Since the java runtime image is always in slot 0 on the shared class path, the
236 // appended entries are started at slot 1 immediately after.
237 for (int cur_entry = 1 ; cpe != NULL; cpe = cpe->next(), cur_entry++) {
238 const char *name = cpe->name();
239 int name_bytes = (int)(strlen(name) + 1);
240 assert(!cpe->is_jrt(), "A modular java runtime image is present on the list of appended entries");
241
242 if (pass == 0) {
243 count ++;
244 bytes += (int)entry_size;
245 bytes += name_bytes;
246 log_info(class, path)("add main shared path (%s) %s", (cpe->is_jar_file() ? "jar" : "dir"), name);
247 } else {
248 SharedClassPathEntry* ent = shared_classpath(cur_entry);
249 if (cpe->is_jar_file()) {
250 struct stat st;
251 if (os::stat(name, &st) != 0) {
252 // The file/dir must exist, or it would not have been added
253 // into ClassLoader::classpath_entry().
254 //
255 // If we can't access a jar file in the boot path, then we can't
256 // make assumptions about where classes get loaded from.
257 FileMapInfo::fail_stop("Unable to open jar file %s.", name);
258 }
259
260 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error.
261 SharedClassUtil::update_shared_classpath(cpe, ent, st.st_mtime, st.st_size, THREAD);
262 } else {
263 struct stat st;
264 if (os::stat(name, &st) == 0) {
265 if ((st.st_mode & S_IFDIR) == S_IFDIR) {
266 if (!os::dir_is_empty(name)) {
267 ClassLoader::exit_with_path_failure(
268 "Cannot have non-empty directory in archived classpaths", name);
269 }
270 ent->_filesize = -1;
271 }
272 }
273 if (ent->_filesize == 0) {
274 // unknown
275 ent->_filesize = -2;
276 }
277 }
278 ent->_name = strptr;
279 if (strptr + name_bytes <= strptr_max) {
280 strncpy(strptr, name, (size_t)name_bytes); // name_bytes includes trailing 0.
281 strptr += name_bytes;
282 } else {
283 assert(0, "miscalculated buffer size");
284 }
285 }
286 }
287
288 if (pass == 0) {
289 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error.
290 Array<u8>* arr = MetadataFactory::new_array<u8>(loader_data, (bytes + 7)/8, THREAD);
291 strptr = (char*)(arr->data());
292 strptr_max = strptr + bytes;
293 SharedClassPathEntry* table = (SharedClassPathEntry*)strptr;
294 strptr += entry_size * count;
295
296 _classpath_entry_table_size = count;
297 _classpath_entry_table = table;
298 _classpath_entry_size = entry_size;
299 }
300 }
301 }
302
303 bool FileMapInfo::validate_classpath_entry_table() {
304 _validating_classpath_entry_table = true;
305
306 int count = _header->_classpath_entry_table_size;
307
308 _classpath_entry_table = _header->_classpath_entry_table;
309 _classpath_entry_size = _header->_classpath_entry_size;
310
311 for (int i=0; i<count; i++) {
312 SharedClassPathEntry* ent = shared_classpath(i);
313 struct stat st;
314 const char* name = ent->_name;
315 bool ok = true;
316 log_info(class, path)("checking shared classpath entry: %s", name);
317 if (os::stat(name, &st) != 0) {
318 fail_continue("Required classpath entry does not exist: %s", name);
319 ok = false;
320 } else if (ent->is_dir()) {
321 if (!os::dir_is_empty(name)) {
322 fail_continue("directory is not empty: %s", name);
323 ok = false;
324 }
325 } else if (ent->is_jar_or_bootimage()) {
326 if (ent->_timestamp != st.st_mtime ||
327 ent->_filesize != st.st_size) {
328 ok = false;
329 if (PrintSharedArchiveAndExit) {
330 fail_continue(ent->_timestamp != st.st_mtime ?
331 "Timestamp mismatch" :
332 "File size mismatch");
333 } else {
334 fail_continue("A jar/jimage file is not the one used while building"
335 " the shared archive file: %s", name);
336 }
337 }
338 }
339 if (ok) {
340 log_info(class, path)("ok");
341 } else if (!PrintSharedArchiveAndExit) {
342 _validating_classpath_entry_table = false;
343 return false;
344 }
345 }
346
347 _classpath_entry_table_size = _header->_classpath_entry_table_size;
348 _validating_classpath_entry_table = false;
349 return true;
350 }
351
352
353 // Read the FileMapInfo information from the file.
354
355 bool FileMapInfo::init_from_file(int fd) {
356 size_t sz = _header->data_size();
357 char* addr = _header->data();
358 size_t n = os::read(fd, addr, (unsigned int)sz);
359 if (n != sz) {
360 fail_continue("Unable to read the file header.");
361 return false;
362 }
363 if (_header->_version != current_version()) {
364 fail_continue("The shared archive file has the wrong version.");
365 return false;
366 }
367 _file_offset = (long)n;
368
369 size_t info_size = _header->_paths_misc_info_size;
370 _paths_misc_info = NEW_C_HEAP_ARRAY_RETURN_NULL(char, info_size, mtClass);
371 if (_paths_misc_info == NULL) {
372 fail_continue("Unable to read the file header.");
373 return false;
374 }
375 n = os::read(fd, _paths_misc_info, (unsigned int)info_size);
376 if (n != info_size) {
377 fail_continue("Unable to read the shared path info header.");
378 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
379 _paths_misc_info = NULL;
380 return false;
381 }
382
383 size_t len = lseek(fd, 0, SEEK_END);
384 struct FileMapInfo::FileMapHeader::space_info* si =
385 &_header->_space[MetaspaceShared::mc];
386 if (si->_file_offset >= len || len - si->_file_offset < si->_used) {
387 fail_continue("The shared archive file has been truncated.");
388 return false;
389 }
390
391 _file_offset += (long)n;
392 return true;
393 }
394
395
396 // Read the FileMapInfo information from the file.
397 bool FileMapInfo::open_for_read() {
398 _full_path = Arguments::GetSharedArchivePath();
399 int fd = open(_full_path, O_RDONLY | O_BINARY, 0);
400 if (fd < 0) {
401 if (errno == ENOENT) {
402 // Not locating the shared archive is ok.
403 fail_continue("Specified shared archive not found.");
404 } else {
405 fail_continue("Failed to open shared archive file (%s).",
406 os::strerror(errno));
407 }
408 return false;
409 }
410
411 _fd = fd;
412 _file_open = true;
413 return true;
414 }
415
416
417 // Write the FileMapInfo information to the file.
418
419 void FileMapInfo::open_for_write() {
420 _full_path = Arguments::GetSharedArchivePath();
421 if (PrintSharedSpaces) {
422 tty->print_cr("Dumping shared data to file: ");
423 tty->print_cr(" %s", _full_path);
424 }
425
426 #ifdef _WINDOWS // On Windows, need WRITE permission to remove the file.
427 chmod(_full_path, _S_IREAD | _S_IWRITE);
428 #endif
429
430 // Use remove() to delete the existing file because, on Unix, this will
431 // allow processes that have it open continued access to the file.
432 remove(_full_path);
433 int fd = open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444);
434 if (fd < 0) {
435 fail_stop("Unable to create shared archive file %s: (%s).", _full_path,
436 os::strerror(errno));
437 }
438 _fd = fd;
439 _file_offset = 0;
440 _file_open = true;
441 }
442
443
444 // Write the header to the file, seek to the next allocation boundary.
445
446 void FileMapInfo::write_header() {
447 int info_size = ClassLoader::get_shared_paths_misc_info_size();
448
449 _header->_paths_misc_info_size = info_size;
450
451 align_file_position();
452 size_t sz = _header->data_size();
453 char* addr = _header->data();
454 write_bytes(addr, (int)sz); // skip the C++ vtable
455 write_bytes(ClassLoader::get_shared_paths_misc_info(), info_size);
456 align_file_position();
457 }
458
459
460 // Dump shared spaces to file.
461
462 void FileMapInfo::write_space(int i, Metaspace* space, bool read_only) {
463 align_file_position();
464 size_t used = space->used_bytes_slow(Metaspace::NonClassType);
465 size_t capacity = space->capacity_bytes_slow(Metaspace::NonClassType);
466 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
467 write_region(i, (char*)space->bottom(), used, capacity, read_only, false);
468 }
469
470
471 // Dump region to file.
472
473 void FileMapInfo::write_region(int region, char* base, size_t size,
474 size_t capacity, bool read_only,
475 bool allow_exec) {
476 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[region];
477
478 if (_file_open) {
479 guarantee(si->_file_offset == _file_offset, "file offset mismatch.");
480 if (PrintSharedSpaces) {
481 tty->print_cr("Shared file region %d: " SIZE_FORMAT_HEX_W(6) " bytes, addr " INTPTR_FORMAT
482 " file offset " SIZE_FORMAT_HEX_W(6), region, size, p2i(base), _file_offset);
483 }
484 } else {
485 si->_file_offset = _file_offset;
486 }
487 if (MetaspaceShared::is_string_region(region)) {
488 assert((base - (char*)Universe::narrow_oop_base()) % HeapWordSize == 0, "Sanity");
489 if (base != NULL) {
490 si->_addr._offset = (intx)oopDesc::encode_heap_oop_not_null((oop)base);
491 } else {
492 si->_addr._offset = 0;
493 }
494 } else {
495 si->_addr._base = base;
496 }
497 si->_used = size;
498 si->_capacity = capacity;
499 si->_read_only = read_only;
500 si->_allow_exec = allow_exec;
501 si->_crc = ClassLoader::crc32(0, base, (jint)size);
502 write_bytes_aligned(base, (int)size);
503 }
504
505 // Write the string space. The string space contains one or multiple GC(G1) regions.
506 // When the total string space size is smaller than one GC region of the dump time,
507 // only one string region is used for shared strings.
508 //
509 // If the total string space size is bigger than one GC region, there would be more
510 // than one GC regions allocated for shared strings. The first/bottom GC region might
511 // be a partial GC region with the empty portion at the higher address within that region.
512 // The non-empty portion of the first region is written into the archive as one string
513 // region. The rest are consecutive full GC regions if they exist, which can be written
514 // out in one chunk as another string region.
515 void FileMapInfo::write_string_regions(GrowableArray<MemRegion> *regions) {
516 for (int i = MetaspaceShared::first_string;
517 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
518 char* start = NULL;
519 size_t size = 0;
520 if (regions->is_nonempty()) {
521 if (i == MetaspaceShared::first_string) {
522 MemRegion first = regions->first();
523 start = (char*)first.start();
524 size = first.byte_size();
525 } else {
526 int len = regions->length();
527 if (len > 1) {
528 start = (char*)regions->at(1).start();
529 size = (char*)regions->at(len - 1).end() - start;
530 }
531 }
532 }
533 write_region(i, start, size, size, false, false);
534 }
535 }
536
537
538 // Dump bytes to file -- at the current file position.
539
540 void FileMapInfo::write_bytes(const void* buffer, int nbytes) {
541 if (_file_open) {
542 int n = ::write(_fd, buffer, nbytes);
543 if (n != nbytes) {
544 // It is dangerous to leave the corrupted shared archive file around,
545 // close and remove the file. See bug 6372906.
546 close();
547 remove(_full_path);
548 fail_stop("Unable to write to shared archive file.");
549 }
550 }
551 _file_offset += nbytes;
552 }
553
554
555 // Align file position to an allocation unit boundary.
556
557 void FileMapInfo::align_file_position() {
558 size_t new_file_offset = align_size_up(_file_offset,
559 os::vm_allocation_granularity());
560 if (new_file_offset != _file_offset) {
561 _file_offset = new_file_offset;
562 if (_file_open) {
563 // Seek one byte back from the target and write a byte to insure
564 // that the written file is the correct length.
565 _file_offset -= 1;
566 if (lseek(_fd, (long)_file_offset, SEEK_SET) < 0) {
567 fail_stop("Unable to seek.");
568 }
569 char zero = 0;
570 write_bytes(&zero, 1);
571 }
572 }
573 }
574
575
576 // Dump bytes to file -- at the current file position.
577
578 void FileMapInfo::write_bytes_aligned(const void* buffer, int nbytes) {
579 align_file_position();
580 write_bytes(buffer, nbytes);
581 align_file_position();
582 }
583
584
585 // Close the shared archive file. This does NOT unmap mapped regions.
586
587 void FileMapInfo::close() {
588 if (_file_open) {
589 if (::close(_fd) < 0) {
590 fail_stop("Unable to close the shared archive file.");
591 }
592 _file_open = false;
593 _fd = -1;
594 }
595 }
596
597
598 // JVM/TI RedefineClasses() support:
599 // Remap the shared readonly space to shared readwrite, private.
600 bool FileMapInfo::remap_shared_readonly_as_readwrite() {
601 int idx = 0;
602 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[idx];
603 if (!si->_read_only) {
604 // the space is already readwrite so we are done
605 return true;
606 }
607 size_t used = si->_used;
608 size_t size = align_size_up(used, os::vm_allocation_granularity());
609 if (!open_for_read()) {
610 return false;
611 }
612 char *addr = _header->region_addr(idx);
613 char *base = os::remap_memory(_fd, _full_path, si->_file_offset,
614 addr, size, false /* !read_only */,
615 si->_allow_exec);
616 close();
617 if (base == NULL) {
618 fail_continue("Unable to remap shared readonly space (errno=%d).", errno);
619 return false;
620 }
621 if (base != addr) {
622 fail_continue("Unable to remap shared readonly space at required address.");
623 return false;
624 }
625 si->_read_only = false;
626 return true;
627 }
628
629 // Map the whole region at once, assumed to be allocated contiguously.
630 ReservedSpace FileMapInfo::reserve_shared_memory() {
631 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[0];
632 char* requested_addr = _header->region_addr(0);
633
634 size_t size = FileMapInfo::shared_spaces_size();
635
636 // Reserve the space first, then map otherwise map will go right over some
637 // other reserved memory (like the code cache).
638 ReservedSpace rs(size, os::vm_allocation_granularity(), false, requested_addr);
639 if (!rs.is_reserved()) {
640 fail_continue("Unable to reserve shared space at required address "
641 INTPTR_FORMAT, p2i(requested_addr));
642 return rs;
643 }
644 // the reserved virtual memory is for mapping class data sharing archive
645 MemTracker::record_virtual_memory_type((address)rs.base(), mtClassShared);
646
647 return rs;
648 }
649
650 // Memory map a region in the address space.
651 static const char* shared_region_name[] = { "ReadOnly", "ReadWrite", "MiscData", "MiscCode",
652 "String1", "String2" };
653
654 char* FileMapInfo::map_region(int i) {
655 assert(!MetaspaceShared::is_string_region(i), "sanity");
656 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
657 size_t used = si->_used;
658 size_t alignment = os::vm_allocation_granularity();
659 size_t size = align_size_up(used, alignment);
660 char *requested_addr = _header->region_addr(i);
661
662 // If a tool agent is in use (debugging enabled), we must map the address space RW
663 if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space()) {
664 si->_read_only = false;
665 }
666
667 // map the contents of the CDS archive in this memory
668 char *base = os::map_memory(_fd, _full_path, si->_file_offset,
669 requested_addr, size, si->_read_only,
670 si->_allow_exec);
671 if (base == NULL || base != requested_addr) {
672 fail_continue("Unable to map %s shared space at required address.", shared_region_name[i]);
673 return NULL;
674 }
675 #ifdef _WINDOWS
676 // This call is Windows-only because the memory_type gets recorded for the other platforms
677 // in method FileMapInfo::reserve_shared_memory(), which is not called on Windows.
678 MemTracker::record_virtual_memory_type((address)base, mtClassShared);
679 #endif
680
681 return base;
682 }
683
684 static MemRegion *string_ranges = NULL;
685 static int num_ranges = 0;
686 bool FileMapInfo::map_string_regions() {
687 #if INCLUDE_ALL_GCS
688 if (UseG1GC && UseCompressedOops && UseCompressedClassPointers) {
689 // Check that all the narrow oop and klass encodings match the archive
690 if (narrow_oop_mode() != Universe::narrow_oop_mode() ||
691 narrow_oop_shift() != Universe::narrow_oop_shift() ||
692 narrow_klass_base() != Universe::narrow_klass_base() ||
693 narrow_klass_shift() != Universe::narrow_klass_shift()) {
694 if (PrintSharedSpaces && _header->_space[MetaspaceShared::first_string]._used > 0) {
695 tty->print_cr("Shared string data from the CDS archive is being ignored. "
696 "The current CompressedOops/CompressedClassPointers encoding differs from "
697 "that archived due to heap size change. The archive was dumped using max heap "
698 "size " UINTX_FORMAT "M.", max_heap_size()/M);
699 }
700 } else {
701 string_ranges = new MemRegion[MetaspaceShared::max_strings];
702 struct FileMapInfo::FileMapHeader::space_info* si;
703
704 for (int i = MetaspaceShared::first_string;
705 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
706 si = &_header->_space[i];
707 size_t used = si->_used;
708 if (used > 0) {
709 size_t size = used;
710 char* requested_addr = (char*)((void*)oopDesc::decode_heap_oop_not_null(
711 (narrowOop)si->_addr._offset));
712 string_ranges[num_ranges] = MemRegion((HeapWord*)requested_addr, size / HeapWordSize);
713 num_ranges ++;
714 }
715 }
716
717 if (num_ranges == 0) {
718 StringTable::ignore_shared_strings(true);
719 return true; // no shared string data
720 }
721
722 // Check that ranges are within the java heap
723 if (!G1CollectedHeap::heap()->check_archive_addresses(string_ranges, num_ranges)) {
724 fail_continue("Unable to allocate shared string space: range is not "
725 "within java heap.");
726 return false;
727 }
728
729 // allocate from java heap
730 if (!G1CollectedHeap::heap()->alloc_archive_regions(string_ranges, num_ranges)) {
731 fail_continue("Unable to allocate shared string space: range is "
732 "already in use.");
733 return false;
734 }
735
736 // Map the string data. No need to call MemTracker::record_virtual_memory_type()
737 // for mapped string regions as they are part of the reserved java heap, which
738 // is already recorded.
739 for (int i = 0; i < num_ranges; i++) {
740 si = &_header->_space[MetaspaceShared::first_string + i];
741 char* addr = (char*)string_ranges[i].start();
742 char* base = os::map_memory(_fd, _full_path, si->_file_offset,
743 addr, string_ranges[i].byte_size(), si->_read_only,
744 si->_allow_exec);
745 if (base == NULL || base != addr) {
746 // dealloc the string regions from java heap
747 dealloc_string_regions();
748 fail_continue("Unable to map shared string space at required address.");
749 return false;
750 }
751 }
752
753 if (!verify_string_regions()) {
754 // dealloc the string regions from java heap
755 dealloc_string_regions();
756 fail_continue("Shared string regions are corrupt");
757 return false;
758 }
759
760 // the shared string data is mapped successfully
761 return true;
762 }
763 } else {
764 if (PrintSharedSpaces && _header->_space[MetaspaceShared::first_string]._used > 0) {
765 tty->print_cr("Shared string data from the CDS archive is being ignored. UseG1GC, "
766 "UseCompressedOops and UseCompressedClassPointers are required.");
767 }
768 }
769
770 // if we get here, the shared string data is not mapped
771 assert(string_ranges == NULL && num_ranges == 0, "sanity");
772 StringTable::ignore_shared_strings(true);
773 #endif
774 return true;
775 }
776
777 bool FileMapInfo::verify_string_regions() {
778 for (int i = MetaspaceShared::first_string;
779 i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
780 if (!verify_region_checksum(i)) {
781 return false;
782 }
783 }
784 return true;
785 }
786
787 void FileMapInfo::fixup_string_regions() {
788 #if INCLUDE_ALL_GCS
789 // If any string regions were found, call the fill routine to make them parseable.
790 // Note that string_ranges may be non-NULL even if no ranges were found.
791 if (num_ranges != 0) {
792 assert(string_ranges != NULL, "Null string_ranges array with non-zero count");
793 G1CollectedHeap::heap()->fill_archive_regions(string_ranges, num_ranges);
794 }
795 #endif
796 }
797
798 bool FileMapInfo::verify_region_checksum(int i) {
799 if (!VerifySharedSpaces) {
800 return true;
801 }
802
803 size_t sz = _header->_space[i]._used;
804
805 if (sz == 0) {
806 return true; // no data
807 }
808 if (MetaspaceShared::is_string_region(i) && StringTable::shared_string_ignored()) {
809 return true; // shared string data are not mapped
810 }
811 const char* buf = _header->region_addr(i);
812 int crc = ClassLoader::crc32(0, buf, (jint)sz);
813 if (crc != _header->_space[i]._crc) {
814 fail_continue("Checksum verification failed.");
815 return false;
816 }
817 return true;
818 }
819
820 // Unmap a memory region in the address space.
821
822 void FileMapInfo::unmap_region(int i) {
823 assert(!MetaspaceShared::is_string_region(i), "sanity");
824 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
825 size_t used = si->_used;
826 size_t size = align_size_up(used, os::vm_allocation_granularity());
827
828 if (used == 0) {
829 return;
830 }
831
832 char* addr = _header->region_addr(i);
833 if (!os::unmap_memory(addr, size)) {
834 fail_stop("Unable to unmap shared space.");
835 }
836 }
837
838 // dealloc the archived string region from java heap
839 void FileMapInfo::dealloc_string_regions() {
840 #if INCLUDE_ALL_GCS
841 if (num_ranges > 0) {
842 assert(string_ranges != NULL, "Null string_ranges array with non-zero count");
843 G1CollectedHeap::heap()->dealloc_archive_regions(string_ranges, num_ranges);
844 }
845 #endif
846 }
847
848 void FileMapInfo::assert_mark(bool check) {
849 if (!check) {
850 fail_stop("Mark mismatch while restoring from shared file.");
851 }
852 }
853
854
855 FileMapInfo* FileMapInfo::_current_info = NULL;
856 SharedClassPathEntry* 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
883 SharedReadOnlySize = _header->_space[0]._capacity;
884 SharedReadWriteSize = _header->_space[1]._capacity;
885 SharedMiscDataSize = _header->_space[2]._capacity;
886 SharedMiscCodeSize = _header->_space[3]._capacity;
887 return true;
888 }
889
890 char* FileMapInfo::FileMapHeader::region_addr(int idx) {
891 if (MetaspaceShared::is_string_region(idx)) {
892 return (char*)((void*)oopDesc::decode_heap_oop_not_null(
893 (narrowOop)_space[idx]._addr._offset));
894 } else {
895 return _space[idx]._addr._base;
896 }
897 }
898
899 int FileMapInfo::FileMapHeader::compute_crc() {
900 char* header = data();
901 // start computing from the field after _crc
902 char* buf = (char*)&_crc + sizeof(int);
903 size_t sz = data_size() - (buf - header);
904 int crc = ClassLoader::crc32(0, buf, (jint)sz);
905 return crc;
906 }
907
908 bool FileMapInfo::FileMapHeader::validate() {
909 if (VerifySharedSpaces && compute_crc() != _crc) {
910 fail_continue("Header checksum verification failed.");
911 return false;
912 }
913
914 if (Arguments::get_patch_mod_prefix() != NULL) {
915 FileMapInfo::fail_continue("The shared archive file cannot be used with --patch-module.");
916 return false;
917 }
918
919 if (!Arguments::has_jimage()) {
920 FileMapInfo::fail_continue("The shared archive file cannot be used with an exploded module build.");
921 return false;
922 }
923
924 if (_version != current_version()) {
925 FileMapInfo::fail_continue("The shared archive file is the wrong version.");
926 return false;
927 }
928 if (_magic != (int)0xf00baba2) {
929 FileMapInfo::fail_continue("The shared archive file has a bad magic number.");
930 return false;
931 }
932 char header_version[JVM_IDENT_MAX];
933 get_header_version(header_version);
934 if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) {
935 log_info(class, path)("expected: %s", header_version);
936 log_info(class, path)("actual: %s", _jvm_ident);
937 FileMapInfo::fail_continue("The shared archive file was created by a different"
938 " version or build of HotSpot");
939 return false;
940 }
941 if (_obj_alignment != ObjectAlignmentInBytes) {
942 FileMapInfo::fail_continue("The shared archive file's ObjectAlignmentInBytes of %d"
943 " does not equal the current ObjectAlignmentInBytes of " INTX_FORMAT ".",
944 _obj_alignment, ObjectAlignmentInBytes);
945 return false;
946 }
947 if (_compact_strings != CompactStrings) {
948 FileMapInfo::fail_continue("The shared archive file's CompactStrings setting (%s)"
949 " does not equal the current CompactStrings setting (%s).",
950 _compact_strings ? "enabled" : "disabled",
951 CompactStrings ? "enabled" : "disabled");
952 return false;
953 }
954
955 return true;
956 }
957
958 bool FileMapInfo::validate_header() {
959 bool status = _header->validate();
960
961 if (status) {
962 if (!ClassLoader::check_shared_paths_misc_info(_paths_misc_info, _header->_paths_misc_info_size)) {
963 if (!PrintSharedArchiveAndExit) {
964 fail_continue("shared class paths mismatch (hint: enable -Xlog:class+path=info to diagnose the failure)");
965 status = false;
966 }
967 }
968 }
969
970 if (_paths_misc_info != NULL) {
971 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
972 _paths_misc_info = NULL;
973 }
974 return status;
975 }
976
977 // The following method is provided to see whether a given pointer
978 // falls in the mapped shared space.
979 // Param:
980 // p, The given pointer
981 // Return:
982 // True if the p is within the mapped shared space, otherwise, false.
983 bool FileMapInfo::is_in_shared_space(const void* p) {
984 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
985 char *base;
986 if (MetaspaceShared::is_string_region(i) && _header->_space[i]._used == 0) {
987 continue;
988 }
989 base = _header->region_addr(i);
990 if (p >= base && p < base + _header->_space[i]._used) {
991 return true;
992 }
993 }
994
995 return false;
996 }
997
998 // Check if a given address is within one of the shared regions (ro, rw, md, mc)
999 bool FileMapInfo::is_in_shared_region(const void* p, int idx) {
1000 assert((idx >= MetaspaceShared::ro) && (idx <= MetaspaceShared::mc), "invalid region index");
1001 char* base = _header->region_addr(idx);
1002 if (p >= base && p < base + _header->_space[idx]._used) {
1003 return true;
1004 }
1005 return false;
1006 }
1007
1008 void FileMapInfo::print_shared_spaces() {
1009 tty->print_cr("Shared Spaces:");
1010 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
1011 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
1012 char *base = _header->region_addr(i);
1013 tty->print(" %s " INTPTR_FORMAT "-" INTPTR_FORMAT,
1014 shared_region_name[i],
1015 p2i(base), p2i(base + si->_used));
1016 }
1017 }
1018
1019 // Unmap mapped regions of shared space.
1020 void FileMapInfo::stop_sharing_and_unmap(const char* msg) {
1021 FileMapInfo *map_info = FileMapInfo::current_info();
1022 if (map_info) {
1023 map_info->fail_continue("%s", msg);
1024 for (int i = 0; i < MetaspaceShared::num_non_strings; i++) {
1025 char *addr = map_info->_header->region_addr(i);
1026 if (addr != NULL && !MetaspaceShared::is_string_region(i)) {
1027 map_info->unmap_region(i);
1028 map_info->_header->_space[i]._addr._base = NULL;
1029 }
1030 }
1031 // Dealloc the string regions only without unmapping. The string regions are part
1032 // of the java heap. Unmapping of the heap regions are managed by GC.
1033 map_info->dealloc_string_regions();
1034 } else if (DumpSharedSpaces) {
1035 fail_stop("%s", msg);
1036 }
1037 }