1 /*
2 * Copyright (c) 2003, 2018, 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 "jvm.h"
27 #include "classfile/classLoader.inline.hpp"
28 #include "classfile/classLoaderExt.hpp"
29 #include "classfile/compactHashtable.inline.hpp"
30 #include "classfile/stringTable.hpp"
31 #include "classfile/symbolTable.hpp"
32 #include "classfile/systemDictionaryShared.hpp"
33 #include "classfile/altHashing.hpp"
34 #include "logging/log.hpp"
35 #include "logging/logStream.hpp"
36 #include "logging/logMessage.hpp"
37 #include "memory/filemap.hpp"
38 #include "memory/metadataFactory.hpp"
39 #include "memory/metaspaceClosure.hpp"
40 #include "memory/metaspaceShared.hpp"
41 #include "memory/oopFactory.hpp"
42 #include "oops/compressedOops.inline.hpp"
43 #include "oops/objArrayOop.hpp"
44 #include "prims/jvmtiExport.hpp"
45 #include "runtime/arguments.hpp"
46 #include "runtime/java.hpp"
47 #include "runtime/os.hpp"
48 #include "runtime/vm_version.hpp"
49 #include "services/memTracker.hpp"
50 #include "utilities/align.hpp"
51 #include "utilities/defaultStream.hpp"
52 #if INCLUDE_G1GC
53 #include "gc/g1/g1CollectedHeap.hpp"
54 #endif
55
56 # include <sys/stat.h>
57 # include <errno.h>
58
59 #ifndef O_BINARY // if defined (Win32) use binary files.
60 #define O_BINARY 0 // otherwise do nothing.
61 #endif
62
63 extern address JVM_FunctionAtStart();
64 extern address JVM_FunctionAtEnd();
65
66 // Complain and stop. All error conditions occurring during the writing of
67 // an archive file should stop the process. Unrecoverable errors during
68 // the reading of the archive file should stop the process.
69
70 static void fail(const char *msg, va_list ap) {
71 // This occurs very early during initialization: tty is not initialized.
72 jio_fprintf(defaultStream::error_stream(),
73 "An error has occurred while processing the"
74 " shared archive file.\n");
75 jio_vfprintf(defaultStream::error_stream(), msg, ap);
76 jio_fprintf(defaultStream::error_stream(), "\n");
77 // Do not change the text of the below message because some tests check for it.
78 vm_exit_during_initialization("Unable to use shared archive.", NULL);
79 }
80
81
82 void FileMapInfo::fail_stop(const char *msg, ...) {
83 va_list ap;
84 va_start(ap, msg);
85 fail(msg, ap); // Never returns.
86 va_end(ap); // for completeness.
87 }
88
89
90 // Complain and continue. Recoverable errors during the reading of the
91 // archive file may continue (with sharing disabled).
92 //
93 // If we continue, then disable shared spaces and close the file.
94
95 void FileMapInfo::fail_continue(const char *msg, ...) {
96 va_list ap;
97 va_start(ap, msg);
98 MetaspaceShared::set_archive_loading_failed();
99 if (PrintSharedArchiveAndExit && _validating_shared_path_table) {
100 // If we are doing PrintSharedArchiveAndExit and some of the classpath entries
101 // do not validate, we can still continue "limping" to validate the remaining
102 // entries. No need to quit.
103 tty->print("[");
104 tty->vprint(msg, ap);
105 tty->print_cr("]");
106 } else {
107 if (RequireSharedSpaces) {
108 fail(msg, ap);
109 } else {
110 if (log_is_enabled(Info, cds)) {
111 ResourceMark rm;
112 LogStream ls(Log(cds)::info());
113 ls.print("UseSharedSpaces: ");
114 ls.vprint_cr(msg, ap);
115 }
116 }
117 UseSharedSpaces = false;
118 assert(current_info() != NULL, "singleton must be registered");
119 current_info()->close();
120 }
121 va_end(ap);
122 }
123
124 // Fill in the fileMapInfo structure with data about this VM instance.
125
126 // This method copies the vm version info into header_version. If the version is too
127 // long then a truncated version, which has a hash code appended to it, is copied.
128 //
129 // Using a template enables this method to verify that header_version is an array of
130 // length JVM_IDENT_MAX. This ensures that the code that writes to the CDS file and
131 // the code that reads the CDS file will both use the same size buffer. Hence, will
132 // use identical truncation. This is necessary for matching of truncated versions.
133 template <int N> static void get_header_version(char (&header_version) [N]) {
134 assert(N == JVM_IDENT_MAX, "Bad header_version size");
135
136 const char *vm_version = VM_Version::internal_vm_info_string();
137 const int version_len = (int)strlen(vm_version);
138
139 if (version_len < (JVM_IDENT_MAX-1)) {
140 strcpy(header_version, vm_version);
141
142 } else {
143 // Get the hash value. Use a static seed because the hash needs to return the same
144 // value over multiple jvm invocations.
145 unsigned int hash = AltHashing::murmur3_32(8191, (const jbyte*)vm_version, version_len);
146
147 // Truncate the ident, saving room for the 8 hex character hash value.
148 strncpy(header_version, vm_version, JVM_IDENT_MAX-9);
149
150 // Append the hash code as eight hex digits.
151 sprintf(&header_version[JVM_IDENT_MAX-9], "%08x", hash);
152 header_version[JVM_IDENT_MAX-1] = 0; // Null terminate.
153 }
154 }
155
156 FileMapInfo::FileMapInfo() {
157 assert(_current_info == NULL, "must be singleton"); // not thread safe
158 _current_info = this;
159 memset((void*)this, 0, sizeof(FileMapInfo));
160 _file_offset = 0;
161 _file_open = false;
162 _header = new FileMapHeader();
163 _header->_version = _invalid_version;
164 _header->_has_platform_or_app_classes = true;
165 }
166
167 FileMapInfo::~FileMapInfo() {
168 assert(_current_info == this, "must be singleton"); // not thread safe
169 _current_info = NULL;
170 }
171
172 void FileMapInfo::populate_header(size_t alignment) {
173 _header->populate(this, alignment);
174 }
175
176 void FileMapInfo::FileMapHeader::populate(FileMapInfo* mapinfo, size_t alignment) {
177 _magic = 0xf00baba2;
178 _version = _current_version;
179 _alignment = alignment;
180 _obj_alignment = ObjectAlignmentInBytes;
181 _compact_strings = CompactStrings;
182 _narrow_oop_mode = Universe::narrow_oop_mode();
183 _narrow_oop_base = Universe::narrow_oop_base();
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 _shared_path_table_size = mapinfo->_shared_path_table_size;
189 _shared_path_table = mapinfo->_shared_path_table;
190 _shared_path_entry_size = mapinfo->_shared_path_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 ClassLoaderExt::finalize_shared_paths_misc_info();
200 _app_class_paths_start_index = ClassLoaderExt::app_class_paths_start_index();
201 _app_module_paths_start_index = ClassLoaderExt::app_module_paths_start_index();
202
203 _verify_local = BytecodeVerificationLocal;
204 _verify_remote = BytecodeVerificationRemote;
205 _has_platform_or_app_classes = ClassLoaderExt::has_platform_or_app_classes();
206 }
207
208 void SharedClassPathEntry::init(const char* name, TRAPS) {
209 _timestamp = 0;
210 _filesize = 0;
211
212 struct stat st;
213 if (os::stat(name, &st) == 0) {
214 if ((st.st_mode & S_IFMT) == S_IFDIR) {
215 _is_dir = true;
216 } else {
217 _is_dir = false;
218 _timestamp = st.st_mtime;
219 _filesize = st.st_size;
220 }
221 } else {
222 // The file/dir must exist, or it would not have been added
223 // into ClassLoader::classpath_entry().
224 //
225 // If we can't access a jar file in the boot path, then we can't
226 // make assumptions about where classes get loaded from.
227 FileMapInfo::fail_stop("Unable to open file %s.", name);
228 }
229
230 size_t len = strlen(name) + 1;
231 _name = MetadataFactory::new_array<char>(ClassLoaderData::the_null_class_loader_data(), (int)len, THREAD);
232 strcpy(_name->data(), name);
233 }
234
235 bool SharedClassPathEntry::validate(bool is_class_path) {
236 assert(UseSharedSpaces, "runtime only");
237
238 struct stat st;
239 const char* name = this->name();
240 bool ok = true;
241 log_info(class, path)("checking shared classpath entry: %s", name);
242 if (os::stat(name, &st) != 0 && is_class_path) {
243 // If the archived module path entry does not exist at runtime, it is not fatal
244 // (no need to invalid the shared archive) because the shared runtime visibility check
245 // filters out any archived module classes that do not have a matching runtime
246 // module path location.
247 FileMapInfo::fail_continue("Required classpath entry does not exist: %s", name);
248 ok = false;
249 } else if (is_dir()) {
250 if (!os::dir_is_empty(name)) {
251 FileMapInfo::fail_continue("directory is not empty: %s", name);
252 ok = false;
253 }
254 } else if (is_jar_or_bootimage()) {
255 if (_timestamp != st.st_mtime ||
256 _filesize != st.st_size) {
257 ok = false;
258 if (PrintSharedArchiveAndExit) {
259 FileMapInfo::fail_continue(_timestamp != st.st_mtime ?
260 "Timestamp mismatch" :
261 "File size mismatch");
262 } else {
263 FileMapInfo::fail_continue("A jar/jimage file is not the one used while building"
264 " the shared archive file: %s", name);
265 }
266 }
267 }
268 return ok;
269 }
270
271 void SharedClassPathEntry::metaspace_pointers_do(MetaspaceClosure* it) {
272 it->push(&_name);
273 it->push(&_manifest);
274 }
275
276 void FileMapInfo::allocate_shared_path_table() {
277 assert(DumpSharedSpaces, "Sanity");
278
279 Thread* THREAD = Thread::current();
280 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
281 ClassPathEntry* jrt = ClassLoader::get_jrt_entry();
282
283 assert(jrt != NULL,
284 "No modular java runtime image present when allocating the CDS classpath entry table");
285
286 size_t entry_size = sizeof(SharedClassPathEntry); // assert ( should be 8 byte aligned??)
287 int num_boot_classpath_entries = ClassLoader::num_boot_classpath_entries();
288 int num_app_classpath_entries = ClassLoader::num_app_classpath_entries();
289 int num_module_path_entries = ClassLoader::num_module_path_entries();
290 int num_entries = num_boot_classpath_entries + num_app_classpath_entries + num_module_path_entries;
291 size_t bytes = entry_size * num_entries;
292
293 _shared_path_table = MetadataFactory::new_array<u8>(loader_data, (int)(bytes + 7 / 8), THREAD);
294 _shared_path_table_size = num_entries;
295 _shared_path_entry_size = entry_size;
296
297 // 1. boot class path
298 int i = 0;
299 ClassPathEntry* cpe = jrt;
300 while (cpe != NULL) {
301 const char* type = ((cpe == jrt) ? "jrt" : (cpe->is_jar_file() ? "jar" : "dir"));
302 log_info(class, path)("add main shared path (%s) %s", type, cpe->name());
303 SharedClassPathEntry* ent = shared_path(i);
304 ent->init(cpe->name(), THREAD);
305 if (cpe != jrt) { // No need to do jimage.
306 EXCEPTION_MARK; // The following call should never throw, but would exit VM on error.
307 update_shared_classpath(cpe, ent, THREAD);
308 }
309 cpe = ClassLoader::get_next_boot_classpath_entry(cpe);
310 i++;
311 }
312 assert(i == num_boot_classpath_entries,
313 "number of boot class path entry mismatch");
314
315 // 2. app class path
316 ClassPathEntry *acpe = ClassLoader::app_classpath_entries();
317 while (acpe != NULL) {
318 log_info(class, path)("add app shared path %s", acpe->name());
319 SharedClassPathEntry* ent = shared_path(i);
320 ent->init(acpe->name(), THREAD);
321 EXCEPTION_MARK;
322 update_shared_classpath(acpe, ent, THREAD);
323 acpe = acpe->next();
324 i++;
325 }
326
327 // 3. module path
328 ClassPathEntry *mpe = ClassLoader::module_path_entries();
329 while (mpe != NULL) {
330 log_info(class, path)("add module path %s",mpe->name());
331 SharedClassPathEntry* ent = shared_path(i);
332 ent->init(mpe->name(), THREAD);
333 EXCEPTION_MARK;
334 update_shared_classpath(mpe, ent, THREAD);
335 mpe = mpe->next();
336 i++;
337 }
338 assert(i == num_entries, "number of shared path entry mismatch");
339 }
340
341 void FileMapInfo::check_nonempty_dir_in_shared_path_table() {
342 assert(DumpSharedSpaces, "dump time only");
343
344 bool has_nonempty_dir = false;
345
346 int end = _shared_path_table_size;
347 if (!ClassLoaderExt::has_platform_or_app_classes()) {
348 // only check the boot path if no app class is loaded
349 end = ClassLoaderExt::app_class_paths_start_index();
350 }
351
352 for (int i = 0; i < end; i++) {
353 SharedClassPathEntry *e = shared_path(i);
354 if (e->is_dir()) {
355 const char* path = e->name();
356 if (!os::dir_is_empty(path)) {
357 tty->print_cr("Error: non-empty directory '%s'", path);
358 has_nonempty_dir = true;
359 }
360 }
361 }
362
363 if (has_nonempty_dir) {
364 ClassLoader::exit_with_path_failure("Cannot have non-empty directory in paths", NULL);
365 }
366 }
367
368 class ManifestStream: public ResourceObj {
369 private:
370 u1* _buffer_start; // Buffer bottom
371 u1* _buffer_end; // Buffer top (one past last element)
372 u1* _current; // Current buffer position
373
374 public:
375 // Constructor
376 ManifestStream(u1* buffer, int length) : _buffer_start(buffer),
377 _current(buffer) {
378 _buffer_end = buffer + length;
379 }
380
381 static bool is_attr(u1* attr, const char* name) {
382 return strncmp((const char*)attr, name, strlen(name)) == 0;
383 }
384
385 static char* copy_attr(u1* value, size_t len) {
386 char* buf = NEW_RESOURCE_ARRAY(char, len + 1);
387 strncpy(buf, (char*)value, len);
388 buf[len] = 0;
389 return buf;
390 }
391
392 // The return value indicates if the JAR is signed or not
393 bool check_is_signed() {
394 u1* attr = _current;
395 bool isSigned = false;
396 while (_current < _buffer_end) {
397 if (*_current == '\n') {
398 *_current = '\0';
399 u1* value = (u1*)strchr((char*)attr, ':');
400 if (value != NULL) {
401 assert(*(value+1) == ' ', "Unrecognized format" );
402 if (strstr((char*)attr, "-Digest") != NULL) {
403 isSigned = true;
404 break;
405 }
406 }
407 *_current = '\n'; // restore
408 attr = _current + 1;
409 }
410 _current ++;
411 }
412 return isSigned;
413 }
414 };
415
416 void FileMapInfo::update_shared_classpath(ClassPathEntry *cpe, SharedClassPathEntry* ent, TRAPS) {
417 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
418 ResourceMark rm(THREAD);
419 jint manifest_size;
420 bool isSigned;
421
422 if (cpe->is_jar_file()) {
423 char* manifest = ClassLoaderExt::read_manifest(cpe, &manifest_size, CHECK);
424 if (manifest != NULL) {
425 ManifestStream* stream = new ManifestStream((u1*)manifest,
426 manifest_size);
427 isSigned = stream->check_is_signed();
428 if (isSigned) {
429 ent->set_is_signed(true);
430 } else {
431 // Copy the manifest into the shared archive
432 manifest = ClassLoaderExt::read_raw_manifest(cpe, &manifest_size, CHECK);
433 Array<u1>* buf = MetadataFactory::new_array<u1>(loader_data,
434 manifest_size,
435 THREAD);
436 char* p = (char*)(buf->data());
437 memcpy(p, manifest, manifest_size);
438 ent->set_manifest(buf);
439 ent->set_is_signed(false);
440 }
441 }
442 }
443 }
444
445
446 bool FileMapInfo::validate_shared_path_table() {
447 assert(UseSharedSpaces, "runtime only");
448
449 _validating_shared_path_table = true;
450 _shared_path_table = _header->_shared_path_table;
451 _shared_path_entry_size = _header->_shared_path_entry_size;
452 _shared_path_table_size = _header->_shared_path_table_size;
453
454 int module_paths_start_index = _header->_app_module_paths_start_index;
455
456 // If the shared archive contain app or platform classes, validate all entries
457 // in the shared path table. Otherwise, only validate the boot path entries (with
458 // entry index < _app_class_paths_start_index).
459 int count = _header->has_platform_or_app_classes() ?
460 _shared_path_table_size : _header->_app_class_paths_start_index;
461
462 for (int i=0; i<count; i++) {
463 if (i < module_paths_start_index) {
464 if (shared_path(i)->validate()) {
465 log_info(class, path)("ok");
466 }
467 } else if (i >= module_paths_start_index) {
468 if (shared_path(i)->validate(false /* not a class path entry */)) {
469 log_info(class, path)("ok");
470 }
471 } else if (!PrintSharedArchiveAndExit) {
472 _validating_shared_path_table = false;
473 _shared_path_table = NULL;
474 _shared_path_table_size = 0;
475 return false;
476 }
477 }
478
479 _validating_shared_path_table = false;
480 return true;
481 }
482
483 // Read the FileMapInfo information from the file.
484
485 bool FileMapInfo::init_from_file(int fd) {
486 size_t sz = _header->data_size();
487 char* addr = _header->data();
488 size_t n = os::read(fd, addr, (unsigned int)sz);
489 if (n != sz) {
490 fail_continue("Unable to read the file header.");
491 return false;
492 }
493 if (_header->_version != current_version()) {
494 fail_continue("The shared archive file has the wrong version.");
495 return false;
496 }
497 _file_offset = (long)n;
498
499 size_t info_size = _header->_paths_misc_info_size;
500 _paths_misc_info = NEW_C_HEAP_ARRAY_RETURN_NULL(char, info_size, mtClass);
501 if (_paths_misc_info == NULL) {
502 fail_continue("Unable to read the file header.");
503 return false;
504 }
505 n = os::read(fd, _paths_misc_info, (unsigned int)info_size);
506 if (n != info_size) {
507 fail_continue("Unable to read the shared path info header.");
508 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
509 _paths_misc_info = NULL;
510 return false;
511 }
512
513 size_t len = lseek(fd, 0, SEEK_END);
514 struct FileMapInfo::FileMapHeader::space_info* si =
515 &_header->_space[MetaspaceShared::last_valid_region];
516 // The last space might be empty
517 if (si->_file_offset > len || len - si->_file_offset < si->_used) {
518 fail_continue("The shared archive file has been truncated.");
519 return false;
520 }
521
522 _file_offset += (long)n;
523 return true;
524 }
525
526
527 // Read the FileMapInfo information from the file.
528 bool FileMapInfo::open_for_read() {
529 _full_path = Arguments::GetSharedArchivePath();
530 int fd = open(_full_path, O_RDONLY | O_BINARY, 0);
531 if (fd < 0) {
532 if (errno == ENOENT) {
533 // Not locating the shared archive is ok.
534 fail_continue("Specified shared archive not found.");
535 } else {
536 fail_continue("Failed to open shared archive file (%s).",
537 os::strerror(errno));
538 }
539 return false;
540 }
541
542 _fd = fd;
543 _file_open = true;
544 return true;
545 }
546
547
548 // Write the FileMapInfo information to the file.
549
550 void FileMapInfo::open_for_write() {
551 _full_path = Arguments::GetSharedArchivePath();
552 LogMessage(cds) msg;
553 if (msg.is_info()) {
554 msg.info("Dumping shared data to file: ");
555 msg.info(" %s", _full_path);
556 }
557
558 #ifdef _WINDOWS // On Windows, need WRITE permission to remove the file.
559 chmod(_full_path, _S_IREAD | _S_IWRITE);
560 #endif
561
562 // Use remove() to delete the existing file because, on Unix, this will
563 // allow processes that have it open continued access to the file.
564 remove(_full_path);
565 int fd = open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444);
566 if (fd < 0) {
567 fail_stop("Unable to create shared archive file %s: (%s).", _full_path,
568 os::strerror(errno));
569 }
570 _fd = fd;
571 _file_offset = 0;
572 _file_open = true;
573 }
574
575
576 // Write the header to the file, seek to the next allocation boundary.
577
578 void FileMapInfo::write_header() {
579 int info_size = ClassLoader::get_shared_paths_misc_info_size();
580
581 _header->_paths_misc_info_size = info_size;
582
583 align_file_position();
584 size_t sz = _header->data_size();
585 char* addr = _header->data();
586 write_bytes(addr, (int)sz); // skip the C++ vtable
587 write_bytes(ClassLoader::get_shared_paths_misc_info(), info_size);
588 align_file_position();
589 }
590
591
592 // Dump region to file.
593
594 void FileMapInfo::write_region(int region, char* base, size_t size,
595 bool read_only, bool allow_exec) {
596 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[region];
597
598 if (_file_open) {
599 guarantee(si->_file_offset == _file_offset, "file offset mismatch.");
600 log_info(cds)("Shared file region %d: " SIZE_FORMAT_HEX_W(08)
601 " bytes, addr " INTPTR_FORMAT " file offset " SIZE_FORMAT_HEX_W(08),
602 region, size, p2i(base), _file_offset);
603 } else {
604 si->_file_offset = _file_offset;
605 }
606 if (MetaspaceShared::is_heap_region(region)) {
607 assert((base - (char*)Universe::narrow_oop_base()) % HeapWordSize == 0, "Sanity");
608 if (base != NULL) {
609 si->_addr._offset = (intx)CompressedOops::encode_not_null((oop)base);
610 } else {
611 si->_addr._offset = 0;
612 }
613 } else {
614 si->_addr._base = base;
615 }
616 si->_used = size;
617 si->_read_only = read_only;
618 si->_allow_exec = allow_exec;
619 si->_crc = ClassLoader::crc32(0, base, (jint)size);
620 write_bytes_aligned(base, (int)size);
621 }
622
623 // Write out the given archive heap memory regions. GC code combines multiple
624 // consecutive archive GC regions into one MemRegion whenever possible and
625 // produces the 'heap_mem' array.
626 //
627 // If the archive heap memory size is smaller than a single dump time GC region
628 // size, there is only one MemRegion in the array.
629 //
630 // If the archive heap memory size is bigger than one dump time GC region size,
631 // the 'heap_mem' array may contain more than one consolidated MemRegions. When
632 // the first/bottom archive GC region is a partial GC region (with the empty
633 // portion at the higher address within the region), one MemRegion is used for
634 // the bottom partial archive GC region. The rest of the consecutive archive
635 // GC regions are combined into another MemRegion.
636 //
637 // Here's the mapping from (archive heap GC regions) -> (GrowableArray<MemRegion> *regions).
638 // + We have 1 or more archive heap regions: ah0, ah1, ah2 ..... ahn
639 // + We have 1 or 2 consolidated heap memory regions: r0 and r1
640 //
641 // If there's a single archive GC region (ah0), then r0 == ah0, and r1 is empty.
642 // Otherwise:
643 //
644 // "X" represented space that's occupied by heap objects.
645 // "_" represented unused spaced in the heap region.
646 //
647 //
648 // |ah0 | ah1 | ah2| ...... | ahn |
649 // |XXXXXX|__ |XXXXX|XXXX|XXXXXXXX|XXXX|
650 // |<-r0->| |<- r1 ----------------->|
651 // ^^^
652 // |
653 // +-- gap
654 size_t FileMapInfo::write_archive_heap_regions(GrowableArray<MemRegion> *heap_mem,
655 int first_region_id, int max_num_regions) {
656 assert(max_num_regions <= 2, "Only support maximum 2 memory regions");
657
658 int arr_len = heap_mem == NULL ? 0 : heap_mem->length();
659 if(arr_len > max_num_regions) {
660 fail_stop("Unable to write archive heap memory regions: "
661 "number of memory regions exceeds maximum due to fragmentation");
662 }
663
664 size_t total_size = 0;
665 for (int i = first_region_id, arr_idx = 0;
666 i < first_region_id + max_num_regions;
667 i++, arr_idx++) {
668 char* start = NULL;
669 size_t size = 0;
670 if (arr_idx < arr_len) {
671 start = (char*)heap_mem->at(arr_idx).start();
672 size = heap_mem->at(arr_idx).byte_size();
673 total_size += size;
674 }
675
676 log_info(cds)("Archive heap region %d " INTPTR_FORMAT " - " INTPTR_FORMAT " = " SIZE_FORMAT_W(8) " bytes",
677 i, p2i(start), p2i(start + size), size);
678 write_region(i, start, size, false, false);
679 }
680 return total_size;
681 }
682
683 // Dump bytes to file -- at the current file position.
684
685 void FileMapInfo::write_bytes(const void* buffer, int nbytes) {
686 if (_file_open) {
687 int n = ::write(_fd, buffer, nbytes);
688 if (n != nbytes) {
689 // It is dangerous to leave the corrupted shared archive file around,
690 // close and remove the file. See bug 6372906.
691 close();
692 remove(_full_path);
693 fail_stop("Unable to write to shared archive file.");
694 }
695 }
696 _file_offset += nbytes;
697 }
698
699
700 // Align file position to an allocation unit boundary.
701
702 void FileMapInfo::align_file_position() {
703 size_t new_file_offset = align_up(_file_offset,
704 os::vm_allocation_granularity());
705 if (new_file_offset != _file_offset) {
706 _file_offset = new_file_offset;
707 if (_file_open) {
708 // Seek one byte back from the target and write a byte to insure
709 // that the written file is the correct length.
710 _file_offset -= 1;
711 if (lseek(_fd, (long)_file_offset, SEEK_SET) < 0) {
712 fail_stop("Unable to seek.");
713 }
714 char zero = 0;
715 write_bytes(&zero, 1);
716 }
717 }
718 }
719
720
721 // Dump bytes to file -- at the current file position.
722
723 void FileMapInfo::write_bytes_aligned(const void* buffer, int nbytes) {
724 align_file_position();
725 write_bytes(buffer, nbytes);
726 align_file_position();
727 }
728
729
730 // Close the shared archive file. This does NOT unmap mapped regions.
731
732 void FileMapInfo::close() {
733 if (_file_open) {
734 if (::close(_fd) < 0) {
735 fail_stop("Unable to close the shared archive file.");
736 }
737 _file_open = false;
738 _fd = -1;
739 }
740 }
741
742
743 // JVM/TI RedefineClasses() support:
744 // Remap the shared readonly space to shared readwrite, private.
745 bool FileMapInfo::remap_shared_readonly_as_readwrite() {
746 int idx = MetaspaceShared::ro;
747 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[idx];
748 if (!si->_read_only) {
749 // the space is already readwrite so we are done
750 return true;
751 }
752 size_t used = si->_used;
753 size_t size = align_up(used, os::vm_allocation_granularity());
754 if (!open_for_read()) {
755 return false;
756 }
757 char *addr = _header->region_addr(idx);
758 char *base = os::remap_memory(_fd, _full_path, si->_file_offset,
759 addr, size, false /* !read_only */,
760 si->_allow_exec);
761 close();
762 if (base == NULL) {
763 fail_continue("Unable to remap shared readonly space (errno=%d).", errno);
764 return false;
765 }
766 if (base != addr) {
767 fail_continue("Unable to remap shared readonly space at required address.");
768 return false;
769 }
770 si->_read_only = false;
771 return true;
772 }
773
774 // Map the whole region at once, assumed to be allocated contiguously.
775 ReservedSpace FileMapInfo::reserve_shared_memory() {
776 char* requested_addr = _header->region_addr(0);
777 size_t size = FileMapInfo::core_spaces_size();
778
779 // Reserve the space first, then map otherwise map will go right over some
780 // other reserved memory (like the code cache).
781 ReservedSpace rs(size, os::vm_allocation_granularity(), false, requested_addr);
782 if (!rs.is_reserved()) {
783 fail_continue("Unable to reserve shared space at required address "
784 INTPTR_FORMAT, p2i(requested_addr));
785 return rs;
786 }
787 // the reserved virtual memory is for mapping class data sharing archive
788 MemTracker::record_virtual_memory_type((address)rs.base(), mtClassShared);
789
790 return rs;
791 }
792
793 // Memory map a region in the address space.
794 static const char* shared_region_name[] = { "MiscData", "ReadWrite", "ReadOnly", "MiscCode", "OptionalData",
795 "String1", "String2", "OpenArchive1", "OpenArchive2" };
796
797 char* FileMapInfo::map_region(int i, char** top_ret) {
798 assert(!MetaspaceShared::is_heap_region(i), "sanity");
799 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
800 size_t used = si->_used;
801 size_t alignment = os::vm_allocation_granularity();
802 size_t size = align_up(used, alignment);
803 char *requested_addr = _header->region_addr(i);
804
805 // If a tool agent is in use (debugging enabled), we must map the address space RW
806 if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space()) {
807 si->_read_only = false;
808 }
809
810 // map the contents of the CDS archive in this memory
811 char *base = os::map_memory(_fd, _full_path, si->_file_offset,
812 requested_addr, size, si->_read_only,
813 si->_allow_exec);
814 if (base == NULL || base != requested_addr) {
815 fail_continue("Unable to map %s shared space at required address.", shared_region_name[i]);
816 return NULL;
817 }
818 #ifdef _WINDOWS
819 // This call is Windows-only because the memory_type gets recorded for the other platforms
820 // in method FileMapInfo::reserve_shared_memory(), which is not called on Windows.
821 MemTracker::record_virtual_memory_type((address)base, mtClassShared);
822 #endif
823
824
825 if (!verify_region_checksum(i)) {
826 return NULL;
827 }
828
829 *top_ret = base + size;
830 return base;
831 }
832
833 static MemRegion *string_ranges = NULL;
834 static MemRegion *open_archive_heap_ranges = NULL;
835 static int num_string_ranges = 0;
836 static int num_open_archive_heap_ranges = 0;
837
838 #if INCLUDE_CDS_JAVA_HEAP
839 //
840 // Map the shared string objects and open archive heap objects to the runtime
841 // java heap.
842 //
843 // The shared strings are mapped near the runtime java heap top. The
844 // mapped strings contain no out-going references to any other java heap
845 // regions. GC does not write into the mapped shared strings.
846 //
847 // The open archive heap objects are mapped below the shared strings in
848 // the runtime java heap. The mapped open archive heap data only contain
849 // references to the shared strings and open archive objects initially.
850 // During runtime execution, out-going references to any other java heap
851 // regions may be added. GC may mark and update references in the mapped
852 // open archive objects.
853 void FileMapInfo::map_heap_regions() {
854 if (MetaspaceShared::is_heap_object_archiving_allowed()) {
855 log_info(cds)("Archived narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d",
856 narrow_oop_mode(), p2i(narrow_oop_base()), narrow_oop_shift());
857 log_info(cds)("Archived narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
858 p2i(narrow_klass_base()), narrow_klass_shift());
859
860 // Check that all the narrow oop and klass encodings match the archive
861 if (narrow_oop_mode() != Universe::narrow_oop_mode() ||
862 narrow_oop_base() != Universe::narrow_oop_base() ||
863 narrow_oop_shift() != Universe::narrow_oop_shift() ||
864 narrow_klass_base() != Universe::narrow_klass_base() ||
865 narrow_klass_shift() != Universe::narrow_klass_shift()) {
866 if (log_is_enabled(Info, cds) && _header->_space[MetaspaceShared::first_string]._used > 0) {
867 log_info(cds)("Cached heap data from the CDS archive is being ignored. "
868 "The current CompressedOops/CompressedClassPointers encoding differs from "
869 "that archived due to heap size change. The archive was dumped using max heap "
870 "size " UINTX_FORMAT "M.", max_heap_size()/M);
871 log_info(cds)("Current narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d",
872 Universe::narrow_oop_mode(), p2i(Universe::narrow_oop_base()),
873 Universe::narrow_oop_shift());
874 log_info(cds)("Current narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
875 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift());
876 }
877 } else {
878 // First, map string regions as closed archive heap regions.
879 // GC does not write into the regions.
880 if (map_heap_data(&string_ranges,
881 MetaspaceShared::first_string,
882 MetaspaceShared::max_strings,
883 &num_string_ranges)) {
884 StringTable::set_shared_string_mapped();
885
886 // Now, map open_archive heap regions, GC can write into the regions.
887 if (map_heap_data(&open_archive_heap_ranges,
888 MetaspaceShared::first_open_archive_heap_region,
889 MetaspaceShared::max_open_archive_heap_region,
890 &num_open_archive_heap_ranges,
891 true /* open */)) {
892 MetaspaceShared::set_open_archive_heap_region_mapped();
893 }
894 }
895 }
896 } else {
897 if (log_is_enabled(Info, cds) && _header->_space[MetaspaceShared::first_string]._used > 0) {
898 log_info(cds)("Cached heap data from the CDS archive is being ignored. UseG1GC, "
899 "UseCompressedOops and UseCompressedClassPointers are required.");
900 }
901 }
902
903 if (!StringTable::shared_string_mapped()) {
904 assert(string_ranges == NULL && num_string_ranges == 0, "sanity");
905 }
906
907 if (!MetaspaceShared::open_archive_heap_region_mapped()) {
908 assert(open_archive_heap_ranges == NULL && num_open_archive_heap_ranges == 0, "sanity");
909 }
910 }
911
912 bool FileMapInfo::map_heap_data(MemRegion **heap_mem, int first,
913 int max, int* num, bool is_open_archive) {
914 MemRegion * regions = new MemRegion[max];
915 struct FileMapInfo::FileMapHeader::space_info* si;
916 int region_num = 0;
917
918 for (int i = first;
919 i < first + max; i++) {
920 si = &_header->_space[i];
921 size_t used = si->_used;
922 if (used > 0) {
923 size_t size = used;
924 char* requested_addr = (char*)((void*)CompressedOops::decode_not_null(
925 (narrowOop)si->_addr._offset));
926 regions[region_num] = MemRegion((HeapWord*)requested_addr, size / HeapWordSize);
927 region_num ++;
928 }
929 }
930
931 if (region_num == 0) {
932 return false; // no archived java heap data
933 }
934
935 // Check that ranges are within the java heap
936 if (!G1CollectedHeap::heap()->check_archive_addresses(regions, region_num)) {
937 log_info(cds)("UseSharedSpaces: Unable to allocate region, "
938 "range is not within java heap.");
939 return false;
940 }
941
942 // allocate from java heap
943 if (!G1CollectedHeap::heap()->alloc_archive_regions(
944 regions, region_num, is_open_archive)) {
945 log_info(cds)("UseSharedSpaces: Unable to allocate region, "
946 "java heap range is already in use.");
947 return false;
948 }
949
950 // Map the archived heap data. No need to call MemTracker::record_virtual_memory_type()
951 // for mapped regions as they are part of the reserved java heap, which is
952 // already recorded.
953 for (int i = 0; i < region_num; i++) {
954 si = &_header->_space[first + i];
955 char* addr = (char*)regions[i].start();
956 char* base = os::map_memory(_fd, _full_path, si->_file_offset,
957 addr, regions[i].byte_size(), si->_read_only,
958 si->_allow_exec);
959 if (base == NULL || base != addr) {
960 // dealloc the regions from java heap
961 dealloc_archive_heap_regions(regions, region_num);
962 log_info(cds)("UseSharedSpaces: Unable to map at required address in java heap.");
963 return false;
964 }
965 }
966
967 if (!verify_mapped_heap_regions(first, region_num)) {
968 // dealloc the regions from java heap
969 dealloc_archive_heap_regions(regions, region_num);
970 log_info(cds)("UseSharedSpaces: mapped heap regions are corrupt");
971 return false;
972 }
973
974 // the shared heap data is mapped successfully
975 *heap_mem = regions;
976 *num = region_num;
977 return true;
978 }
979
980 bool FileMapInfo::verify_mapped_heap_regions(int first, int num) {
981 for (int i = first;
982 i <= first + num; i++) {
983 if (!verify_region_checksum(i)) {
984 return false;
985 }
986 }
987 return true;
988 }
989
990 void FileMapInfo::fixup_mapped_heap_regions() {
991 // If any string regions were found, call the fill routine to make them parseable.
992 // Note that string_ranges may be non-NULL even if no ranges were found.
993 if (num_string_ranges != 0) {
994 assert(string_ranges != NULL, "Null string_ranges array with non-zero count");
995 G1CollectedHeap::heap()->fill_archive_regions(string_ranges, num_string_ranges);
996 }
997
998 // do the same for mapped open archive heap regions
999 if (num_open_archive_heap_ranges != 0) {
1000 assert(open_archive_heap_ranges != NULL, "NULL open_archive_heap_ranges array with non-zero count");
1001 G1CollectedHeap::heap()->fill_archive_regions(open_archive_heap_ranges,
1002 num_open_archive_heap_ranges);
1003 }
1004 }
1005
1006 // dealloc the archive regions from java heap
1007 void FileMapInfo::dealloc_archive_heap_regions(MemRegion* regions, int num) {
1008 if (num > 0) {
1009 assert(regions != NULL, "Null archive ranges array with non-zero count");
1010 G1CollectedHeap::heap()->dealloc_archive_regions(regions, num);
1011 }
1012 }
1013 #endif // INCLUDE_CDS_JAVA_HEAP
1014
1015 bool FileMapInfo::verify_region_checksum(int i) {
1016 if (!VerifySharedSpaces) {
1017 return true;
1018 }
1019
1020 size_t sz = _header->_space[i]._used;
1021
1022 if (sz == 0) {
1023 return true; // no data
1024 }
1025 if ((MetaspaceShared::is_string_region(i) &&
1026 !StringTable::shared_string_mapped()) ||
1027 (MetaspaceShared::is_open_archive_heap_region(i) &&
1028 !MetaspaceShared::open_archive_heap_region_mapped())) {
1029 return true; // archived heap data is not mapped
1030 }
1031 const char* buf = _header->region_addr(i);
1032 int crc = ClassLoader::crc32(0, buf, (jint)sz);
1033 if (crc != _header->_space[i]._crc) {
1034 fail_continue("Checksum verification failed.");
1035 return false;
1036 }
1037 return true;
1038 }
1039
1040 // Unmap a memory region in the address space.
1041
1042 void FileMapInfo::unmap_region(int i) {
1043 assert(!MetaspaceShared::is_heap_region(i), "sanity");
1044 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
1045 size_t used = si->_used;
1046 size_t size = align_up(used, os::vm_allocation_granularity());
1047
1048 if (used == 0) {
1049 return;
1050 }
1051
1052 char* addr = _header->region_addr(i);
1053 if (!os::unmap_memory(addr, size)) {
1054 fail_stop("Unable to unmap shared space.");
1055 }
1056 }
1057
1058 void FileMapInfo::assert_mark(bool check) {
1059 if (!check) {
1060 fail_stop("Mark mismatch while restoring from shared file.");
1061 }
1062 }
1063
1064 void FileMapInfo::metaspace_pointers_do(MetaspaceClosure* it) {
1065 it->push(&_shared_path_table);
1066 for (int i=0; i<_shared_path_table_size; i++) {
1067 shared_path(i)->metaspace_pointers_do(it);
1068 }
1069 }
1070
1071
1072 FileMapInfo* FileMapInfo::_current_info = NULL;
1073 Array<u8>* FileMapInfo::_shared_path_table = NULL;
1074 int FileMapInfo::_shared_path_table_size = 0;
1075 size_t FileMapInfo::_shared_path_entry_size = 0x1234baad;
1076 bool FileMapInfo::_validating_shared_path_table = false;
1077
1078 // Open the shared archive file, read and validate the header
1079 // information (version, boot classpath, etc.). If initialization
1080 // fails, shared spaces are disabled and the file is closed. [See
1081 // fail_continue.]
1082 //
1083 // Validation of the archive is done in two steps:
1084 //
1085 // [1] validate_header() - done here. This checks the header, including _paths_misc_info.
1086 // [2] validate_shared_path_table - this is done later, because the table is in the RW
1087 // region of the archive, which is not mapped yet.
1088 bool FileMapInfo::initialize() {
1089 assert(UseSharedSpaces, "UseSharedSpaces expected.");
1090
1091 if (!open_for_read()) {
1092 return false;
1093 }
1094
1095 init_from_file(_fd);
1096 if (!validate_header()) {
1097 return false;
1098 }
1099 return true;
1100 }
1101
1102 char* FileMapInfo::FileMapHeader::region_addr(int idx) {
1103 if (MetaspaceShared::is_heap_region(idx)) {
1104 return _space[idx]._used > 0 ?
1105 (char*)((void*)CompressedOops::decode_not_null((narrowOop)_space[idx]._addr._offset)) : NULL;
1106 } else {
1107 return _space[idx]._addr._base;
1108 }
1109 }
1110
1111 int FileMapInfo::FileMapHeader::compute_crc() {
1112 char* header = data();
1113 // start computing from the field after _crc
1114 char* buf = (char*)&_crc + sizeof(int);
1115 size_t sz = data_size() - (buf - header);
1116 int crc = ClassLoader::crc32(0, buf, (jint)sz);
1117 return crc;
1118 }
1119
1120 // This function should only be called during run time with UseSharedSpaces enabled.
1121 bool FileMapInfo::FileMapHeader::validate() {
1122 if (VerifySharedSpaces && compute_crc() != _crc) {
1123 fail_continue("Header checksum verification failed.");
1124 return false;
1125 }
1126
1127 if (!Arguments::has_jimage()) {
1128 FileMapInfo::fail_continue("The shared archive file cannot be used with an exploded module build.");
1129 return false;
1130 }
1131
1132 if (_version != current_version()) {
1133 FileMapInfo::fail_continue("The shared archive file is the wrong version.");
1134 return false;
1135 }
1136 if (_magic != (int)0xf00baba2) {
1137 FileMapInfo::fail_continue("The shared archive file has a bad magic number.");
1138 return false;
1139 }
1140 char header_version[JVM_IDENT_MAX];
1141 get_header_version(header_version);
1142 if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) {
1143 log_info(class, path)("expected: %s", header_version);
1144 log_info(class, path)("actual: %s", _jvm_ident);
1145 FileMapInfo::fail_continue("The shared archive file was created by a different"
1146 " version or build of HotSpot");
1147 return false;
1148 }
1149 if (_obj_alignment != ObjectAlignmentInBytes) {
1150 FileMapInfo::fail_continue("The shared archive file's ObjectAlignmentInBytes of %d"
1151 " does not equal the current ObjectAlignmentInBytes of " INTX_FORMAT ".",
1152 _obj_alignment, ObjectAlignmentInBytes);
1153 return false;
1154 }
1155 if (_compact_strings != CompactStrings) {
1156 FileMapInfo::fail_continue("The shared archive file's CompactStrings setting (%s)"
1157 " does not equal the current CompactStrings setting (%s).",
1158 _compact_strings ? "enabled" : "disabled",
1159 CompactStrings ? "enabled" : "disabled");
1160 return false;
1161 }
1162
1163 // This must be done after header validation because it might change the
1164 // header data
1165 const char* prop = Arguments::get_property("java.system.class.loader");
1166 if (prop != NULL) {
1167 warning("Archived non-system classes are disabled because the "
1168 "java.system.class.loader property is specified (value = \"%s\"). "
1169 "To use archived non-system classes, this property must be not be set", prop);
1170 _has_platform_or_app_classes = false;
1171 }
1172
1173 // For backwards compatibility, we don't check the verification setting
1174 // if the archive only contains system classes.
1175 if (_has_platform_or_app_classes &&
1176 ((!_verify_local && BytecodeVerificationLocal) ||
1177 (!_verify_remote && BytecodeVerificationRemote))) {
1178 FileMapInfo::fail_continue("The shared archive file was created with less restrictive "
1179 "verification setting than the current setting.");
1180 return false;
1181 }
1182
1183 return true;
1184 }
1185
1186 bool FileMapInfo::validate_header() {
1187 bool status = _header->validate();
1188
1189 if (status) {
1190 if (!ClassLoader::check_shared_paths_misc_info(_paths_misc_info, _header->_paths_misc_info_size)) {
1191 if (!PrintSharedArchiveAndExit) {
1192 fail_continue("shared class paths mismatch (hint: enable -Xlog:class+path=info to diagnose the failure)");
1193 status = false;
1194 }
1195 }
1196 }
1197
1198 if (_paths_misc_info != NULL) {
1199 FREE_C_HEAP_ARRAY(char, _paths_misc_info);
1200 _paths_misc_info = NULL;
1201 }
1202 return status;
1203 }
1204
1205 // Check if a given address is within one of the shared regions
1206 bool FileMapInfo::is_in_shared_region(const void* p, int idx) {
1207 assert(idx == MetaspaceShared::ro ||
1208 idx == MetaspaceShared::rw ||
1209 idx == MetaspaceShared::mc ||
1210 idx == MetaspaceShared::md, "invalid region index");
1211 char* base = _header->region_addr(idx);
1212 if (p >= base && p < base + _header->_space[idx]._used) {
1213 return true;
1214 }
1215 return false;
1216 }
1217
1218 void FileMapInfo::print_shared_spaces() {
1219 tty->print_cr("Shared Spaces:");
1220 for (int i = 0; i < MetaspaceShared::n_regions; i++) {
1221 struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
1222 char *base = _header->region_addr(i);
1223 tty->print(" %s " INTPTR_FORMAT "-" INTPTR_FORMAT,
1224 shared_region_name[i],
1225 p2i(base), p2i(base + si->_used));
1226 }
1227 }
1228
1229 // Unmap mapped regions of shared space.
1230 void FileMapInfo::stop_sharing_and_unmap(const char* msg) {
1231 FileMapInfo *map_info = FileMapInfo::current_info();
1232 if (map_info) {
1233 map_info->fail_continue("%s", msg);
1234 for (int i = 0; i < MetaspaceShared::num_non_heap_spaces; i++) {
1235 char *addr = map_info->_header->region_addr(i);
1236 if (addr != NULL && !MetaspaceShared::is_heap_region(i)) {
1237 map_info->unmap_region(i);
1238 map_info->_header->_space[i]._addr._base = NULL;
1239 }
1240 }
1241 // Dealloc the archive heap regions only without unmapping. The regions are part
1242 // of the java heap. Unmapping of the heap regions are managed by GC.
1243 map_info->dealloc_archive_heap_regions(open_archive_heap_ranges,
1244 num_open_archive_heap_ranges);
1245 map_info->dealloc_archive_heap_regions(string_ranges, num_string_ranges);
1246 } else if (DumpSharedSpaces) {
1247 fail_stop("%s", msg);
1248 }
1249 }