/*
* Copyright (c) 2003, 2019, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#include "precompiled.hpp"
#include "jvm.h"
#include "classfile/classFileStream.hpp"
#include "classfile/classLoader.inline.hpp"
#include "classfile/classLoaderData.inline.hpp"
#include "classfile/classLoaderExt.hpp"
#include "classfile/symbolTable.hpp"
#include "classfile/systemDictionaryShared.hpp"
#include "classfile/altHashing.hpp"
#include "logging/log.hpp"
#include "logging/logStream.hpp"
#include "logging/logMessage.hpp"
#include "memory/dynamicArchive.hpp"
#include "memory/filemap.hpp"
#include "memory/heapShared.inline.hpp"
#include "memory/iterator.inline.hpp"
#include "memory/metadataFactory.hpp"
#include "memory/metaspaceClosure.hpp"
#include "memory/metaspaceShared.hpp"
#include "memory/oopFactory.hpp"
#include "memory/universe.hpp"
#include "oops/compressedOops.hpp"
#include "oops/compressedOops.inline.hpp"
#include "oops/objArrayOop.hpp"
#include "oops/oop.inline.hpp"
#include "prims/jvmtiExport.hpp"
#include "runtime/arguments.hpp"
#include "runtime/java.hpp"
#include "runtime/mutexLocker.hpp"
#include "runtime/os.inline.hpp"
#include "runtime/vm_version.hpp"
#include "services/memTracker.hpp"
#include "utilities/align.hpp"
#include "utilities/defaultStream.hpp"
#if INCLUDE_G1GC
#include "gc/g1/g1CollectedHeap.hpp"
#include "gc/g1/heapRegion.hpp"
#endif
# include <sys/stat.h>
# include <errno.h>
#ifndef O_BINARY // if defined (Win32) use binary files.
#define O_BINARY 0 // otherwise do nothing.
#endif
extern address JVM_FunctionAtStart();
extern address JVM_FunctionAtEnd();
// Complain and stop. All error conditions occurring during the writing of
// an archive file should stop the process. Unrecoverable errors during
// the reading of the archive file should stop the process.
static void fail_exit(const char *msg, va_list ap) {
// This occurs very early during initialization: tty is not initialized.
jio_fprintf(defaultStream::error_stream(),
"An error has occurred while processing the"
" shared archive file.\n");
jio_vfprintf(defaultStream::error_stream(), msg, ap);
jio_fprintf(defaultStream::error_stream(), "\n");
// Do not change the text of the below message because some tests check for it.
vm_exit_during_initialization("Unable to use shared archive.", NULL);
}
void FileMapInfo::fail_stop(const char *msg, ...) {
va_list ap;
va_start(ap, msg);
fail_exit(msg, ap); // Never returns.
va_end(ap); // for completeness.
}
// Complain and continue. Recoverable errors during the reading of the
// archive file may continue (with sharing disabled).
//
// If we continue, then disable shared spaces and close the file.
void FileMapInfo::fail_continue(const char *msg, ...) {
va_list ap;
va_start(ap, msg);
if (_dynamic_archive_info == NULL) {
MetaspaceShared::set_archive_loading_failed();
} else {
// _dynamic_archive_info has been setup after mapping the base archive
DynamicArchive::disable();
}
if (PrintSharedArchiveAndExit && _validating_shared_path_table) {
// If we are doing PrintSharedArchiveAndExit and some of the classpath entries
// do not validate, we can still continue "limping" to validate the remaining
// entries. No need to quit.
tty->print("[");
tty->vprint(msg, ap);
tty->print_cr("]");
} else {
if (RequireSharedSpaces) {
fail_exit(msg, ap);
} else {
if (log_is_enabled(Info, cds)) {
ResourceMark rm;
LogStream ls(Log(cds)::info());
ls.print("UseSharedSpaces: ");
ls.vprint_cr(msg, ap);
}
}
if (_dynamic_archive_info == NULL) {
UseSharedSpaces = false;
assert(current_info() != NULL, "singleton must be registered");
current_info()->close();
} else {
// We are failing when loading the top archive, but the base archive should
// continue to work.
log_warning(cds, dynamic)("Unable to use shared archive. The top archive failed to load: %s", _dynamic_archive_info->_full_path);
}
}
va_end(ap);
}
// Fill in the fileMapInfo structure with data about this VM instance.
// This method copies the vm version info into header_version. If the version is too
// long then a truncated version, which has a hash code appended to it, is copied.
//
// Using a template enables this method to verify that header_version is an array of
// length JVM_IDENT_MAX. This ensures that the code that writes to the CDS file and
// the code that reads the CDS file will both use the same size buffer. Hence, will
// use identical truncation. This is necessary for matching of truncated versions.
template <int N> static void get_header_version(char (&header_version) [N]) {
assert(N == JVM_IDENT_MAX, "Bad header_version size");
const char *vm_version = VM_Version::internal_vm_info_string();
const int version_len = (int)strlen(vm_version);
memset(header_version, 0, JVM_IDENT_MAX);
if (version_len < (JVM_IDENT_MAX-1)) {
strcpy(header_version, vm_version);
} else {
// Get the hash value. Use a static seed because the hash needs to return the same
// value over multiple jvm invocations.
unsigned int hash = AltHashing::murmur3_32(8191, (const jbyte*)vm_version, version_len);
// Truncate the ident, saving room for the 8 hex character hash value.
strncpy(header_version, vm_version, JVM_IDENT_MAX-9);
// Append the hash code as eight hex digits.
sprintf(&header_version[JVM_IDENT_MAX-9], "%08x", hash);
header_version[JVM_IDENT_MAX-1] = 0; // Null terminate.
}
assert(header_version[JVM_IDENT_MAX-1] == 0, "must be");
}
FileMapInfo::FileMapInfo(bool is_static) {
memset((void*)this, 0, sizeof(FileMapInfo));
_is_static = is_static;
size_t header_size;
if (is_static) {
assert(_current_info == NULL, "must be singleton"); // not thread safe
_current_info = this;
header_size = sizeof(FileMapHeader);
} else {
assert(_dynamic_archive_info == NULL, "must be singleton"); // not thread safe
_dynamic_archive_info = this;
header_size = sizeof(DynamicArchiveHeader);
}
_header = (FileMapHeader*)os::malloc(header_size, mtInternal);
memset((void*)_header, 0, header_size);
_header->_header_size = header_size;
_header->_version = INVALID_CDS_ARCHIVE_VERSION;
_header->_has_platform_or_app_classes = true;
_file_offset = 0;
_file_open = false;
}
FileMapInfo::~FileMapInfo() {
if (_is_static) {
assert(_current_info == this, "must be singleton"); // not thread safe
_current_info = NULL;
} else {
assert(_dynamic_archive_info == this, "must be singleton"); // not thread safe
_dynamic_archive_info = NULL;
}
}
void FileMapInfo::populate_header(size_t alignment) {
_header->populate(this, alignment);
}
void FileMapHeader::populate(FileMapInfo* mapinfo, size_t alignment) {
if (DynamicDumpSharedSpaces) {
_magic = CDS_DYNAMIC_ARCHIVE_MAGIC;
} else {
_magic = CDS_ARCHIVE_MAGIC;
}
_version = CURRENT_CDS_ARCHIVE_VERSION;
_alignment = alignment;
_obj_alignment = ObjectAlignmentInBytes;
_compact_strings = CompactStrings;
_narrow_oop_mode = CompressedOops::mode();
_narrow_oop_base = CompressedOops::base();
_narrow_oop_shift = CompressedOops::shift();
_max_heap_size = MaxHeapSize;
_narrow_klass_base = CompressedKlassPointers::base();
_narrow_klass_shift = CompressedKlassPointers::shift();
_shared_path_table = mapinfo->_shared_path_table;
if (HeapShared::is_heap_object_archiving_allowed()) {
_heap_reserved = Universe::heap()->reserved_region();
}
// The following fields are for sanity checks for whether this archive
// will function correctly with this JVM and the bootclasspath it's
// invoked with.
// JVM version string ... changes on each build.
get_header_version(_jvm_ident);
ClassLoaderExt::finalize_shared_paths_misc_info();
_app_class_paths_start_index = ClassLoaderExt::app_class_paths_start_index();
_app_module_paths_start_index = ClassLoaderExt::app_module_paths_start_index();
_num_module_paths = ClassLoader::num_module_path_entries();
_max_used_path_index = ClassLoaderExt::max_used_path_index();
_verify_local = BytecodeVerificationLocal;
_verify_remote = BytecodeVerificationRemote;
_has_platform_or_app_classes = ClassLoaderExt::has_platform_or_app_classes();
_shared_base_address = SharedBaseAddress;
_allow_archiving_with_java_agent = AllowArchivingWithJavaAgent;
// the following 2 fields will be set in write_header for dynamic archive header
_base_archive_name_size = 0;
_base_archive_is_default = false;
}
void SharedClassPathEntry::init(bool is_modules_image,
ClassPathEntry* cpe, TRAPS) {
assert(DumpSharedSpaces || DynamicDumpSharedSpaces, "dump time only");
_timestamp = 0;
_filesize = 0;
_from_class_path_attr = false;
struct stat st;
if (os::stat(cpe->name(), &st) == 0) {
if ((st.st_mode & S_IFMT) == S_IFDIR) {
_type = dir_entry;
} else {
// The timestamp of the modules_image is not checked at runtime.
if (is_modules_image) {
_type = modules_image_entry;
} else {
_type = jar_entry;
_timestamp = st.st_mtime;
_from_class_path_attr = cpe->from_class_path_attr();
}
_filesize = st.st_size;
}
} else {
// The file/dir must exist, or it would not have been added
// into ClassLoader::classpath_entry().
//
// If we can't access a jar file in the boot path, then we can't
// make assumptions about where classes get loaded from.
FileMapInfo::fail_stop("Unable to open file %s.", cpe->name());
}
size_t len = strlen(cpe->name()) + 1;
_name = MetadataFactory::new_array<char>(ClassLoaderData::the_null_class_loader_data(), (int)len, THREAD);
strcpy(_name->data(), cpe->name());
}
bool SharedClassPathEntry::validate(bool is_class_path) {
assert(UseSharedSpaces, "runtime only");
struct stat st;
const char* name;
// In order to validate the runtime modules image file size against the archived
// size information, we need to obtain the runtime modules image path. The recorded
// dump time modules image path in the archive may be different from the runtime path
// if the JDK image has beed moved after generating the archive.
if (is_modules_image()) {
name = ClassLoader::get_jrt_entry()->name();
} else {
name = this->name();
}
bool ok = true;
log_info(class, path)("checking shared classpath entry: %s", name);
if (os::stat(name, &st) != 0 && is_class_path) {
// If the archived module path entry does not exist at runtime, it is not fatal
// (no need to invalid the shared archive) because the shared runtime visibility check
// filters out any archived module classes that do not have a matching runtime
// module path location.
FileMapInfo::fail_continue("Required classpath entry does not exist: %s", name);
ok = false;
} else if (is_dir()) {
if (!os::dir_is_empty(name)) {
FileMapInfo::fail_continue("directory is not empty: %s", name);
ok = false;
}
} else if ((has_timestamp() && _timestamp != st.st_mtime) ||
_filesize != st.st_size) {
ok = false;
if (PrintSharedArchiveAndExit) {
FileMapInfo::fail_continue(_timestamp != st.st_mtime ?
"Timestamp mismatch" :
"File size mismatch");
} else {
FileMapInfo::fail_continue("A jar file is not the one used while building"
" the shared archive file: %s", name);
}
}
if (PrintSharedArchiveAndExit && !ok) {
// If PrintSharedArchiveAndExit is enabled, don't report failure to the
// caller. Please see above comments for more details.
ok = true;
MetaspaceShared::set_archive_loading_failed();
}
return ok;
}
void SharedClassPathEntry::metaspace_pointers_do(MetaspaceClosure* it) {
it->push(&_name);
it->push(&_manifest);
}
void SharedPathTable::metaspace_pointers_do(MetaspaceClosure* it) {
it->push(&_table);
for (int i=0; i<_size; i++) {
path_at(i)->metaspace_pointers_do(it);
}
}
void SharedPathTable::dumptime_init(ClassLoaderData* loader_data, Thread* THREAD) {
size_t entry_size = sizeof(SharedClassPathEntry);
int num_boot_classpath_entries = ClassLoader::num_boot_classpath_entries();
int num_app_classpath_entries = ClassLoader::num_app_classpath_entries();
int num_module_path_entries = ClassLoader::num_module_path_entries();
int num_entries = num_boot_classpath_entries + num_app_classpath_entries + num_module_path_entries;
size_t bytes = entry_size * num_entries;
_table = MetadataFactory::new_array<u8>(loader_data, (int)(bytes + 7 / 8), THREAD);
_size = num_entries;
}
void FileMapInfo::allocate_shared_path_table() {
assert(DumpSharedSpaces || DynamicDumpSharedSpaces, "Sanity");
Thread* THREAD = Thread::current();
ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
ClassPathEntry* jrt = ClassLoader::get_jrt_entry();
assert(jrt != NULL,
"No modular java runtime image present when allocating the CDS classpath entry table");
_shared_path_table.dumptime_init(loader_data, THREAD);
// 1. boot class path
int i = 0;
ClassPathEntry* cpe = jrt;
while (cpe != NULL) {
bool is_jrt = (cpe == jrt);
const char* type = (is_jrt ? "jrt" : (cpe->is_jar_file() ? "jar" : "dir"));
log_info(class, path)("add main shared path (%s) %s", type, cpe->name());
SharedClassPathEntry* ent = shared_path(i);
ent->init(is_jrt, cpe, THREAD);
if (!is_jrt) { // No need to do the modules image.
EXCEPTION_MARK; // The following call should never throw, but would exit VM on error.
update_shared_classpath(cpe, ent, THREAD);
}
cpe = ClassLoader::get_next_boot_classpath_entry(cpe);
i++;
}
assert(i == ClassLoader::num_boot_classpath_entries(),
"number of boot class path entry mismatch");
// 2. app class path
ClassPathEntry *acpe = ClassLoader::app_classpath_entries();
while (acpe != NULL) {
log_info(class, path)("add app shared path %s", acpe->name());
SharedClassPathEntry* ent = shared_path(i);
ent->init(false, acpe, THREAD);
EXCEPTION_MARK;
update_shared_classpath(acpe, ent, THREAD);
acpe = acpe->next();
i++;
}
// 3. module path
ClassPathEntry *mpe = ClassLoader::module_path_entries();
while (mpe != NULL) {
log_info(class, path)("add module path %s",mpe->name());
SharedClassPathEntry* ent = shared_path(i);
ent->init(false, mpe, THREAD);
EXCEPTION_MARK;
update_shared_classpath(mpe, ent, THREAD);
mpe = mpe->next();
i++;
}
assert(i == _shared_path_table.size(), "number of shared path entry mismatch");
}
void FileMapInfo::check_nonempty_dir_in_shared_path_table() {
assert(DumpSharedSpaces || DynamicDumpSharedSpaces, "dump time only");
bool has_nonempty_dir = false;
int last = _shared_path_table.size() - 1;
if (last > ClassLoaderExt::max_used_path_index()) {
// no need to check any path beyond max_used_path_index
last = ClassLoaderExt::max_used_path_index();
}
for (int i = 0; i <= last; i++) {
SharedClassPathEntry *e = shared_path(i);
if (e->is_dir()) {
const char* path = e->name();
if (!os::dir_is_empty(path)) {
tty->print_cr("Error: non-empty directory '%s'", path);
has_nonempty_dir = true;
}
}
}
if (has_nonempty_dir) {
ClassLoader::exit_with_path_failure("Cannot have non-empty directory in paths", NULL);
}
}
class ManifestStream: public ResourceObj {
private:
u1* _buffer_start; // Buffer bottom
u1* _buffer_end; // Buffer top (one past last element)
u1* _current; // Current buffer position
public:
// Constructor
ManifestStream(u1* buffer, int length) : _buffer_start(buffer),
_current(buffer) {
_buffer_end = buffer + length;
}
static bool is_attr(u1* attr, const char* name) {
return strncmp((const char*)attr, name, strlen(name)) == 0;
}
static char* copy_attr(u1* value, size_t len) {
char* buf = NEW_RESOURCE_ARRAY(char, len + 1);
strncpy(buf, (char*)value, len);
buf[len] = 0;
return buf;
}
// The return value indicates if the JAR is signed or not
bool check_is_signed() {
u1* attr = _current;
bool isSigned = false;
while (_current < _buffer_end) {
if (*_current == '\n') {
*_current = '\0';
u1* value = (u1*)strchr((char*)attr, ':');
if (value != NULL) {
assert(*(value+1) == ' ', "Unrecognized format" );
if (strstr((char*)attr, "-Digest") != NULL) {
isSigned = true;
break;
}
}
*_current = '\n'; // restore
attr = _current + 1;
}
_current ++;
}
return isSigned;
}
};
void FileMapInfo::update_shared_classpath(ClassPathEntry *cpe, SharedClassPathEntry* ent, TRAPS) {
ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
ResourceMark rm(THREAD);
jint manifest_size;
if (cpe->is_jar_file()) {
assert(ent->is_jar(), "the shared class path entry is not a JAR file");
char* manifest = ClassLoaderExt::read_manifest(cpe, &manifest_size, CHECK);
if (manifest != NULL) {
ManifestStream* stream = new ManifestStream((u1*)manifest,
manifest_size);
if (stream->check_is_signed()) {
ent->set_is_signed();
} else {
// Copy the manifest into the shared archive
manifest = ClassLoaderExt::read_raw_manifest(cpe, &manifest_size, CHECK);
Array<u1>* buf = MetadataFactory::new_array<u1>(loader_data,
manifest_size,
THREAD);
char* p = (char*)(buf->data());
memcpy(p, manifest, manifest_size);
ent->set_manifest(buf);
}
}
}
}
char* FileMapInfo::skip_first_path_entry(const char* path) {
size_t path_sep_len = strlen(os::path_separator());
char* p = strstr((char*)path, os::path_separator());
if (p != NULL) {
debug_only( {
size_t image_name_len = strlen(MODULES_IMAGE_NAME);
assert(strncmp(p - image_name_len, MODULES_IMAGE_NAME, image_name_len) == 0,
"first entry must be the modules image");
} );
p += path_sep_len;
} else {
debug_only( {
assert(ClassLoader::string_ends_with(path, MODULES_IMAGE_NAME),
"first entry must be the modules image");
} );
}
return p;
}
int FileMapInfo::num_paths(const char* path) {
if (path == NULL) {
return 0;
}
int npaths = 1;
char* p = (char*)path;
while (p != NULL) {
char* prev = p;
p = strstr((char*)p, os::path_separator());
if (p != NULL) {
p++;
// don't count empty path
if ((p - prev) > 1) {
npaths++;
}
}
}
return npaths;
}
GrowableArray<char*>* FileMapInfo::create_path_array(const char* path) {
GrowableArray<char*>* path_array = new(ResourceObj::RESOURCE_AREA, mtInternal)
GrowableArray<char*>(10);
char* begin_ptr = (char*)path;
char* end_ptr = strchr((char*)path, os::path_separator()[0]);
if (end_ptr == NULL) {
end_ptr = strchr((char*)path, '\0');
}
while (end_ptr != NULL) {
if ((end_ptr - begin_ptr) > 1) {
struct stat st;
char* temp_name = NEW_RESOURCE_ARRAY(char, (size_t)(end_ptr - begin_ptr + 1));
strncpy(temp_name, begin_ptr, end_ptr - begin_ptr);
temp_name[end_ptr - begin_ptr] = '\0';
if (os::stat(temp_name, &st) == 0) {
path_array->append(temp_name);
}
}
if (end_ptr < (path + strlen(path))) {
begin_ptr = ++end_ptr;
end_ptr = strchr(begin_ptr, os::path_separator()[0]);
if (end_ptr == NULL) {
end_ptr = strchr(begin_ptr, '\0');
}
} else {
break;
}
}
return path_array;
}
bool FileMapInfo::fail(const char* msg, const char* name) {
ClassLoader::trace_class_path(msg, name);
MetaspaceShared::set_archive_loading_failed();
return false;
}
bool FileMapInfo::check_paths(int shared_path_start_idx, int num_paths, GrowableArray<char*>* rp_array) {
int i = 0;
int j = shared_path_start_idx;
bool mismatch = false;
while (i < num_paths && !mismatch) {
while (shared_path(j)->from_class_path_attr()) {
// shared_path(j) was expanded from the JAR file attribute "Class-Path:"
// during dump time. It's not included in the -classpath VM argument.
j++;
}
if (!os::same_files(shared_path(j)->name(), rp_array->at(i))) {
mismatch = true;
}
i++;
j++;
}
return mismatch;
}
bool FileMapInfo::validate_boot_class_paths() {
//
// - Archive contains boot classes only - relaxed boot path check:
// Extra path elements appended to the boot path at runtime are allowed.
//
// - Archive contains application or platform classes - strict boot path check:
// Validate the entire runtime boot path, which must be compatible
// with the dump time boot path. Appending boot path at runtime is not
// allowed.
//
// The first entry in boot path is the modules_image (guaranteed by
// ClassLoader::setup_boot_search_path()). Skip the first entry. The
// path of the runtime modules_image may be different from the dump
// time path (e.g. the JDK image is copied to a different location
// after generating the shared archive), which is acceptable. For most
// common cases, the dump time boot path might contain modules_image only.
char* runtime_boot_path = Arguments::get_sysclasspath();
char* rp = skip_first_path_entry(runtime_boot_path);
assert(shared_path(0)->is_modules_image(), "first shared_path must be the modules image");
int dp_len = _header->_app_class_paths_start_index - 1; // ignore the first path to the module image
bool mismatch = false;
bool relaxed_check = !header()->has_platform_or_app_classes();
if (dp_len == 0 && rp == NULL) {
return true; // ok, both runtime and dump time boot paths have modules_images only
} else if (dp_len == 0 && rp != NULL) {
if (relaxed_check) {
return true; // ok, relaxed check, runtime has extra boot append path entries
} else {
mismatch = true;
}
} else if (dp_len > 0 && rp != NULL) {
int num;
ResourceMark rm;
GrowableArray<char*>* rp_array = create_path_array(rp);
int rp_len = rp_array->length();
if (rp_len >= dp_len) {
if (relaxed_check) {
// only check the leading entries in the runtime boot path, up to
// the length of the dump time boot path
num = dp_len;
} else {
// check the full runtime boot path, must match with dump time
num = rp_len;
}
mismatch = check_paths(1, num, rp_array);
}
}
if (mismatch) {
// The paths are different
return fail("[BOOT classpath mismatch, actual =", runtime_boot_path);
}
return true;
}
bool FileMapInfo::validate_app_class_paths(int shared_app_paths_len) {
const char *appcp = Arguments::get_appclasspath();
assert(appcp != NULL, "NULL app classpath");
int rp_len = num_paths(appcp);
bool mismatch = false;
if (rp_len < shared_app_paths_len) {
return fail("Run time APP classpath is shorter than the one at dump time: ", appcp);
}
if (shared_app_paths_len != 0 && rp_len != 0) {
// Prefix is OK: E.g., dump with -cp foo.jar, but run with -cp foo.jar:bar.jar.
ResourceMark rm;
GrowableArray<char*>* rp_array = create_path_array(appcp);
if (rp_array->length() == 0) {
// None of the jar file specified in the runtime -cp exists.
return fail("None of the jar file specified in the runtime -cp exists: -Djava.class.path=", appcp);
}
int j = _header->_app_class_paths_start_index;
mismatch = check_paths(j, shared_app_paths_len, rp_array);
if (mismatch) {
return fail("[APP classpath mismatch, actual: -Djava.class.path=", appcp);
}
}
return true;
}
bool FileMapInfo::validate_shared_path_table() {
assert(UseSharedSpaces, "runtime only");
_validating_shared_path_table = true;
// Load the shared path table info from the archive header
_shared_path_table = _header->_shared_path_table;
if (DynamicDumpSharedSpaces) {
// Only support dynamic dumping with the usage of the default CDS archive
// or a simple base archive.
// If the base layer archive contains additional path component besides
// the runtime image and the -cp, dynamic dumping is disabled.
//
// When dynamic archiving is enabled, the _shared_path_table is overwritten
// to include the application path and stored in the top layer archive.
assert(shared_path(0)->is_modules_image(), "first shared_path must be the modules image");
if (_header->_app_class_paths_start_index > 1) {
DynamicDumpSharedSpaces = false;
warning(
"Dynamic archiving is disabled because base layer archive has appended boot classpath");
}
if (_header->_num_module_paths > 0) {
DynamicDumpSharedSpaces = false;
warning(
"Dynamic archiving is disabled because base layer archive has module path");
}
}
int module_paths_start_index = _header->_app_module_paths_start_index;
int shared_app_paths_len = 0;
// validate the path entries up to the _max_used_path_index
for (int i=0; i < _header->_max_used_path_index + 1; i++) {
if (i < module_paths_start_index) {
if (shared_path(i)->validate()) {
// Only count the app class paths not from the "Class-path" attribute of a jar manifest.
if (!shared_path(i)->from_class_path_attr() && i >= _header->_app_class_paths_start_index) {
shared_app_paths_len++;
}
log_info(class, path)("ok");
} else {
if (_dynamic_archive_info != NULL && _dynamic_archive_info->_is_static) {
assert(!UseSharedSpaces, "UseSharedSpaces should be disabled");
}
return false;
}
} else if (i >= module_paths_start_index) {
if (shared_path(i)->validate(false /* not a class path entry */)) {
log_info(class, path)("ok");
} else {
if (_dynamic_archive_info != NULL && _dynamic_archive_info->_is_static) {
assert(!UseSharedSpaces, "UseSharedSpaces should be disabled");
}
return false;
}
}
}
if (_header->_max_used_path_index == 0) {
// default archive only contains the module image in the bootclasspath
assert(shared_path(0)->is_modules_image(), "first shared_path must be the modules image");
} else {
if (!validate_boot_class_paths() || !validate_app_class_paths(shared_app_paths_len)) {
fail_continue("shared class paths mismatch (hint: enable -Xlog:class+path=info to diagnose the failure)");
return false;
}
}
_validating_shared_path_table = false;
#if INCLUDE_JVMTI
if (_classpath_entries_for_jvmti != NULL) {
os::free(_classpath_entries_for_jvmti);
}
size_t sz = sizeof(ClassPathEntry*) * get_number_of_shared_paths();
_classpath_entries_for_jvmti = (ClassPathEntry**)os::malloc(sz, mtClass);
memset((void*)_classpath_entries_for_jvmti, 0, sz);
#endif
return true;
}
bool FileMapInfo::check_archive(const char* archive_name, bool is_static) {
int fd = os::open(archive_name, O_RDONLY | O_BINARY, 0);
if (fd < 0) {
// do not vm_exit_during_initialization here because Arguments::init_shared_archive_paths()
// requires a shared archive name. The open_for_read() function will log a message regarding
// failure in opening a shared archive.
return false;
}
size_t sz = is_static ? sizeof(FileMapHeader) : sizeof(DynamicArchiveHeader);
void* header = os::malloc(sz, mtInternal);
memset(header, 0, sz);
size_t n = os::read(fd, header, (unsigned int)sz);
if (n != sz) {
os::free(header);
os::close(fd);
vm_exit_during_initialization("Unable to read header from shared archive", archive_name);
return false;
}
if (is_static) {
FileMapHeader* static_header = (FileMapHeader*)header;
if (static_header->_magic != CDS_ARCHIVE_MAGIC) {
os::free(header);
os::close(fd);
vm_exit_during_initialization("Not a base shared archive", archive_name);
return false;
}
} else {
DynamicArchiveHeader* dynamic_header = (DynamicArchiveHeader*)header;
if (dynamic_header->_magic != CDS_DYNAMIC_ARCHIVE_MAGIC) {
os::free(header);
os::close(fd);
vm_exit_during_initialization("Not a top shared archive", archive_name);
return false;
}
}
os::free(header);
os::close(fd);
return true;
}
bool FileMapInfo::get_base_archive_name_from_header(const char* archive_name,
int* size, char** base_archive_name) {
int fd = os::open(archive_name, O_RDONLY | O_BINARY, 0);
if (fd < 0) {
*size = 0;
return false;
}
// read the header as a dynamic archive header
size_t sz = sizeof(DynamicArchiveHeader);
DynamicArchiveHeader* dynamic_header = (DynamicArchiveHeader*)os::malloc(sz, mtInternal);
size_t n = os::read(fd, dynamic_header, (unsigned int)sz);
if (n != sz) {
fail_continue("Unable to read the file header.");
os::free(dynamic_header);
os::close(fd);
return false;
}
if (dynamic_header->_magic != CDS_DYNAMIC_ARCHIVE_MAGIC) {
// Not a dynamic header, no need to proceed further.
*size = 0;
os::free(dynamic_header);
os::close(fd);
return false;
}
if (dynamic_header->_base_archive_is_default) {
*base_archive_name = Arguments::get_default_shared_archive_path();
} else {
// skip over the _paths_misc_info
sz = dynamic_header->_paths_misc_info_size;
lseek(fd, (long)sz, SEEK_CUR);
// read the base archive name
size_t name_size = dynamic_header->_base_archive_name_size;
if (name_size == 0) {
os::free(dynamic_header);
os::close(fd);
return false;
}
*base_archive_name = NEW_C_HEAP_ARRAY(char, name_size, mtInternal);
n = os::read(fd, *base_archive_name, (unsigned int)name_size);
if (n != name_size) {
fail_continue("Unable to read the base archive name from the header.");
FREE_C_HEAP_ARRAY(char, *base_archive_name);
*base_archive_name = NULL;
os::free(dynamic_header);
os::close(fd);
return false;
}
}
os::free(dynamic_header);
os::close(fd);
return true;
}
void FileMapInfo::restore_shared_path_table() {
_shared_path_table = _current_info->_header->_shared_path_table;
}
// Read the FileMapInfo information from the file.
bool FileMapInfo::init_from_file(int fd, bool is_static) {
size_t sz = is_static ? sizeof(FileMapHeader) : sizeof(DynamicArchiveHeader);
size_t n = os::read(fd, _header, (unsigned int)sz);
if (n != sz) {
fail_continue("Unable to read the file header.");
return false;
}
if (!Arguments::has_jimage()) {
FileMapInfo::fail_continue("The shared archive file cannot be used with an exploded module build.");
return false;
}
unsigned int expected_magic = is_static ? CDS_ARCHIVE_MAGIC : CDS_DYNAMIC_ARCHIVE_MAGIC;
if (_header->_magic != expected_magic) {
log_info(cds)("_magic expected: 0x%08x", expected_magic);
log_info(cds)(" actual: 0x%08x", _header->_magic);
FileMapInfo::fail_continue("The shared archive file has a bad magic number.");
return false;
}
if (_header->_version != CURRENT_CDS_ARCHIVE_VERSION) {
log_info(cds)("_version expected: %d", CURRENT_CDS_ARCHIVE_VERSION);
log_info(cds)(" actual: %d", _header->_version);
fail_continue("The shared archive file has the wrong version.");
return false;
}
if (_header->_header_size != sz) {
log_info(cds)("_header_size expected: " SIZE_FORMAT, sz);
log_info(cds)(" actual: " SIZE_FORMAT, _header->_header_size);
FileMapInfo::fail_continue("The shared archive file has an incorrect header size.");
return false;
}
if (_header->_jvm_ident[JVM_IDENT_MAX-1] != 0) {
FileMapInfo::fail_continue("JVM version identifier is corrupted.");
return false;
}
char header_version[JVM_IDENT_MAX];
get_header_version(header_version);
if (strncmp(_header->_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) {
log_info(cds)("_jvm_ident expected: %s", header_version);
log_info(cds)(" actual: %s", _header->_jvm_ident);
FileMapInfo::fail_continue("The shared archive file was created by a different"
" version or build of HotSpot");
return false;
}
if (VerifySharedSpaces) {
int expected_crc = _header->compute_crc();
if (expected_crc != _header->_crc) {
log_info(cds)("_crc expected: %d", expected_crc);
log_info(cds)(" actual: %d", _header->_crc);
FileMapInfo::fail_continue("Header checksum verification failed.");
return false;
}
}
_file_offset = n;
size_t info_size = _header->_paths_misc_info_size;
_paths_misc_info = NEW_C_HEAP_ARRAY(char, info_size, mtClass);
n = os::read(fd, _paths_misc_info, (unsigned int)info_size);
if (n != info_size) {
fail_continue("Unable to read the shared path info header.");
FREE_C_HEAP_ARRAY(char, _paths_misc_info);
_paths_misc_info = NULL;
return false;
}
_file_offset += n + _header->_base_archive_name_size; // accounts for the size of _base_archive_name
if (is_static) {
// just checking the last region is sufficient since the archive is written
// in sequential order
size_t len = lseek(fd, 0, SEEK_END);
CDSFileMapRegion* si = space_at(MetaspaceShared::last_valid_region);
// The last space might be empty
if (si->_file_offset > len || len - si->_file_offset < si->_used) {
fail_continue("The shared archive file has been truncated.");
return false;
}
SharedBaseAddress = _header->_shared_base_address;
}
return true;
}
// Read the FileMapInfo information from the file.
bool FileMapInfo::open_for_read(const char* path) {
if (_file_open) {
return true;
}
if (path == NULL) {
_full_path = Arguments::GetSharedArchivePath();
} else {
_full_path = path;
}
int fd = os::open(_full_path, O_RDONLY | O_BINARY, 0);
if (fd < 0) {
if (errno == ENOENT) {
// Not locating the shared archive is ok.
fail_continue("Specified shared archive not found (%s).", _full_path);
} else {
fail_continue("Failed to open shared archive file (%s).",
os::strerror(errno));
}
return false;
}
_fd = fd;
_file_open = true;
return true;
}
// Write the FileMapInfo information to the file.
void FileMapInfo::open_for_write(const char* path) {
if (path == NULL) {
_full_path = Arguments::GetSharedArchivePath();
} else {
_full_path = path;
}
LogMessage(cds) msg;
if (msg.is_info()) {
msg.info("Dumping shared data to file: ");
msg.info(" %s", _full_path);
}
#ifdef _WINDOWS // On Windows, need WRITE permission to remove the file.
chmod(_full_path, _S_IREAD | _S_IWRITE);
#endif
// Use remove() to delete the existing file because, on Unix, this will
// allow processes that have it open continued access to the file.
remove(_full_path);
int fd = os::open(_full_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0444);
if (fd < 0) {
fail_stop("Unable to create shared archive file %s: (%s).", _full_path,
os::strerror(errno));
}
_fd = fd;
_file_offset = 0;
_file_open = true;
}
// Write the header to the file, seek to the next allocation boundary.
void FileMapInfo::write_header() {
int info_size = ClassLoader::get_shared_paths_misc_info_size();
_header->_paths_misc_info_size = info_size;
char* base_archive_name = NULL;
if (_header->_magic == CDS_DYNAMIC_ARCHIVE_MAGIC) {
base_archive_name = (char*)Arguments::GetSharedArchivePath();
_header->_base_archive_name_size = (int)strlen(base_archive_name) + 1;
_header->_base_archive_is_default = FLAG_IS_DEFAULT(SharedArchiveFile);
}
assert(is_file_position_aligned(), "must be");
write_bytes(_header, _header->_header_size);
write_bytes(ClassLoader::get_shared_paths_misc_info(), (size_t)info_size);
if (base_archive_name != NULL) {
write_bytes(base_archive_name, (size_t)_header->_base_archive_name_size);
}
align_file_position();
}
// Dump region to file.
// This is called twice for each region during archiving, once before
// the archive file is open (_file_open is false) and once after.
void FileMapInfo::write_region(int region, char* base, size_t size,
bool read_only, bool allow_exec) {
assert(DumpSharedSpaces || DynamicDumpSharedSpaces, "Dump time only");
CDSFileMapRegion* si = space_at(region);
char* target_base = base;
if (DynamicDumpSharedSpaces) {
target_base = DynamicArchive::buffer_to_target(base);
}
if (_file_open) {
guarantee(si->_file_offset == _file_offset, "file offset mismatch.");
log_info(cds)("Shared file region %d: " SIZE_FORMAT_HEX_W(08)
" bytes, addr " INTPTR_FORMAT " file offset " SIZE_FORMAT_HEX_W(08),
region, size, p2i(target_base), _file_offset);
} else {
si->_file_offset = _file_offset;
}
if (HeapShared::is_heap_region(region)) {
assert((target_base - (char*)CompressedKlassPointers::base()) % HeapWordSize == 0, "Sanity");
if (target_base != NULL) {
si->_addr._offset = (intx)CompressedOops::encode_not_null((oop)target_base);
} else {
si->_addr._offset = 0;
}
} else {
si->_addr._base = target_base;
}
si->_used = size;
si->_read_only = read_only;
si->_allow_exec = allow_exec;
// Use the current 'base' when computing the CRC value and writing out data
si->_crc = ClassLoader::crc32(0, base, (jint)size);
if (base != NULL) {
write_bytes_aligned(base, size);
}
}
// Write out the given archive heap memory regions. GC code combines multiple
// consecutive archive GC regions into one MemRegion whenever possible and
// produces the 'heap_mem' array.
//
// If the archive heap memory size is smaller than a single dump time GC region
// size, there is only one MemRegion in the array.
//
// If the archive heap memory size is bigger than one dump time GC region size,
// the 'heap_mem' array may contain more than one consolidated MemRegions. When
// the first/bottom archive GC region is a partial GC region (with the empty
// portion at the higher address within the region), one MemRegion is used for
// the bottom partial archive GC region. The rest of the consecutive archive
// GC regions are combined into another MemRegion.
//
// Here's the mapping from (archive heap GC regions) -> (GrowableArray<MemRegion> *regions).
// + We have 1 or more archive heap regions: ah0, ah1, ah2 ..... ahn
// + We have 1 or 2 consolidated heap memory regions: r0 and r1
//
// If there's a single archive GC region (ah0), then r0 == ah0, and r1 is empty.
// Otherwise:
//
// "X" represented space that's occupied by heap objects.
// "_" represented unused spaced in the heap region.
//
//
// |ah0 | ah1 | ah2| ...... | ahn|
// |XXXXXX|__ |XXXXX|XXXX|XXXXXXXX|XXXX|
// |<-r0->| |<- r1 ----------------->|
// ^^^
// |
// +-- gap
size_t FileMapInfo::write_archive_heap_regions(GrowableArray<MemRegion> *heap_mem,
GrowableArray<ArchiveHeapOopmapInfo> *oopmaps,
int first_region_id, int max_num_regions,
bool print_log) {
assert(max_num_regions <= 2, "Only support maximum 2 memory regions");
int arr_len = heap_mem == NULL ? 0 : heap_mem->length();
if(arr_len > max_num_regions) {
fail_stop("Unable to write archive heap memory regions: "
"number of memory regions exceeds maximum due to fragmentation. "
"Please increase java heap size "
"(current MaxHeapSize is " SIZE_FORMAT ", InitialHeapSize is " SIZE_FORMAT ").",
MaxHeapSize, InitialHeapSize);
}
size_t total_size = 0;
for (int i = first_region_id, arr_idx = 0;
i < first_region_id + max_num_regions;
i++, arr_idx++) {
char* start = NULL;
size_t size = 0;
if (arr_idx < arr_len) {
start = (char*)heap_mem->at(arr_idx).start();
size = heap_mem->at(arr_idx).byte_size();
total_size += size;
}
if (print_log) {
log_info(cds)("Archive heap region %d " INTPTR_FORMAT " - " INTPTR_FORMAT " = " SIZE_FORMAT_W(8) " bytes",
i, p2i(start), p2i(start + size), size);
}
write_region(i, start, size, false, false);
if (size > 0) {
space_at(i)->_oopmap = oopmaps->at(arr_idx)._oopmap;
space_at(i)->_oopmap_size_in_bits = oopmaps->at(arr_idx)._oopmap_size_in_bits;
}
}
return total_size;
}
// Dump bytes to file -- at the current file position.
void FileMapInfo::write_bytes(const void* buffer, size_t nbytes) {
if (_file_open) {
size_t n = os::write(_fd, buffer, (unsigned int)nbytes);
if (n != nbytes) {
// If the shared archive is corrupted, close it and remove it.
close();
remove(_full_path);
fail_stop("Unable to write to shared archive file.");
}
}
_file_offset += nbytes;
}
bool FileMapInfo::is_file_position_aligned() const {
return _file_offset == align_up(_file_offset,
os::vm_allocation_granularity());
}
// Align file position to an allocation unit boundary.
void FileMapInfo::align_file_position() {
size_t new_file_offset = align_up(_file_offset,
os::vm_allocation_granularity());
if (new_file_offset != _file_offset) {
_file_offset = new_file_offset;
if (_file_open) {
// Seek one byte back from the target and write a byte to insure
// that the written file is the correct length.
_file_offset -= 1;
if (lseek(_fd, (long)_file_offset, SEEK_SET) < 0) {
fail_stop("Unable to seek.");
}
char zero = 0;
write_bytes(&zero, 1);
}
}
}
// Dump bytes to file -- at the current file position.
void FileMapInfo::write_bytes_aligned(const void* buffer, size_t nbytes) {
align_file_position();
write_bytes(buffer, nbytes);
align_file_position();
}
// Close the shared archive file. This does NOT unmap mapped regions.
void FileMapInfo::close() {
if (_file_open) {
if (::close(_fd) < 0) {
fail_stop("Unable to close the shared archive file.");
}
_file_open = false;
_fd = -1;
}
}
// JVM/TI RedefineClasses() support:
// Remap the shared readonly space to shared readwrite, private.
bool FileMapInfo::remap_shared_readonly_as_readwrite() {
int idx = MetaspaceShared::ro;
CDSFileMapRegion* si = space_at(idx);
if (!si->_read_only) {
// the space is already readwrite so we are done
return true;
}
size_t used = si->_used;
size_t size = align_up(used, os::vm_allocation_granularity());
if (!open_for_read()) {
return false;
}
char *addr = region_addr(idx);
char *base = os::remap_memory(_fd, _full_path, si->_file_offset,
addr, size, false /* !read_only */,
si->_allow_exec);
close();
// These have to be errors because the shared region is now unmapped.
if (base == NULL) {
log_error(cds)("Unable to remap shared readonly space (errno=%d).", errno);
vm_exit(1);
}
if (base != addr) {
log_error(cds)("Unable to remap shared readonly space (errno=%d).", errno);
vm_exit(1);
}
si->_read_only = false;
return true;
}
// Map the whole region at once, assumed to be allocated contiguously.
ReservedSpace FileMapInfo::reserve_shared_memory() {
char* requested_addr = region_addr(0);
size_t size = FileMapInfo::core_spaces_size();
// Reserve the space first, then map otherwise map will go right over some
// other reserved memory (like the code cache).
ReservedSpace rs(size, os::vm_allocation_granularity(), false, requested_addr);
if (!rs.is_reserved()) {
fail_continue("Unable to reserve shared space at required address "
INTPTR_FORMAT, p2i(requested_addr));
return rs;
}
// the reserved virtual memory is for mapping class data sharing archive
MemTracker::record_virtual_memory_type((address)rs.base(), mtClassShared);
return rs;
}
// Memory map a region in the address space.
static const char* shared_region_name[] = { "MiscData", "ReadWrite", "ReadOnly", "MiscCode",
"String1", "String2", "OpenArchive1", "OpenArchive2" };
char* FileMapInfo::map_regions(int regions[], char* saved_base[], size_t len) {
char* prev_top = NULL;
char* curr_base;
char* curr_top;
int i = 0;
for (i = 0; i < (int)len; i++) {
curr_base = map_region(regions[i], &curr_top);
if (curr_base == NULL) {
return NULL;
}
if (i > 0) {
// We require that mc->rw->ro->md to be laid out consecutively, with no
// gaps between them. That way, we can ensure that the OS won't be able to
// allocate any new memory spaces inside _shared_metaspace_{base,top}, which
// would mess up the simple comparision in MetaspaceShared::is_in_shared_metaspace().
assert(curr_base == prev_top, "must be");
}
log_info(cds)("Mapped region #%d at base %p top %p", regions[i], curr_base, curr_top);
saved_base[i] = curr_base;
prev_top = curr_top;
}
return curr_top;
}
char* FileMapInfo::map_region(int i, char** top_ret) {
assert(!HeapShared::is_heap_region(i), "sanity");
CDSFileMapRegion* si = space_at(i);
size_t used = si->_used;
size_t alignment = os::vm_allocation_granularity();
size_t size = align_up(used, alignment);
char *requested_addr = region_addr(i);
#ifdef _WINDOWS
// Windows cannot remap read-only shared memory to read-write when required for
// RedefineClasses, which is also used by JFR. Always map windows regions as RW.
si->_read_only = false;
#else
// If a tool agent is in use (debugging enabled), or JFR, we must map the address space RW
if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space() ||
Arguments::has_jfr_option()) {
si->_read_only = false;
}
#endif // _WINDOWS
// map the contents of the CDS archive in this memory
char *base = os::map_memory(_fd, _full_path, si->_file_offset,
requested_addr, size, si->_read_only,
si->_allow_exec);
if (base == NULL || base != requested_addr) {
fail_continue("Unable to map %s shared space at required address.", shared_region_name[i]);
_memory_mapping_failed = true;
return NULL;
}
#ifdef _WINDOWS
// This call is Windows-only because the memory_type gets recorded for the other platforms
// in method FileMapInfo::reserve_shared_memory(), which is not called on Windows.
MemTracker::record_virtual_memory_type((address)base, mtClassShared);
#endif
if (VerifySharedSpaces && !verify_region_checksum(i)) {
return NULL;
}
*top_ret = base + size;
return base;
}
size_t FileMapInfo::read_bytes(void* buffer, size_t count) {
assert(_file_open, "Archive file is not open");
size_t n = os::read(_fd, buffer, (unsigned int)count);
if (n != count) {
// Close the file if there's a problem reading it.
close();
return 0;
}
_file_offset += count;
return count;
}
address FileMapInfo::decode_start_address(CDSFileMapRegion* spc, bool with_current_oop_encoding_mode) {
if (with_current_oop_encoding_mode) {
return (address)CompressedOops::decode_not_null(offset_of_space(spc));
} else {
return (address)HeapShared::decode_from_archive(offset_of_space(spc));
}
}
static MemRegion *closed_archive_heap_ranges = NULL;
static MemRegion *open_archive_heap_ranges = NULL;
static int num_closed_archive_heap_ranges = 0;
static int num_open_archive_heap_ranges = 0;
#if INCLUDE_CDS_JAVA_HEAP
bool FileMapInfo::has_heap_regions() {
return (_header->_space[MetaspaceShared::first_closed_archive_heap_region]._used > 0);
}
// Returns the address range of the archived heap regions computed using the
// current oop encoding mode. This range may be different than the one seen at
// dump time due to encoding mode differences. The result is used in determining
// if/how these regions should be relocated at run time.
MemRegion FileMapInfo::get_heap_regions_range_with_current_oop_encoding_mode() {
address start = (address) max_uintx;
address end = NULL;
for (int i = MetaspaceShared::first_closed_archive_heap_region;
i <= MetaspaceShared::last_valid_region;
i++) {
CDSFileMapRegion* si = space_at(i);
size_t size = si->_used;
if (size > 0) {
address s = start_address_as_decoded_with_current_oop_encoding_mode(si);
address e = s + size;
if (start > s) {
start = s;
}
if (end < e) {
end = e;
}
}
}
assert(end != NULL, "must have at least one used heap region");
return MemRegion((HeapWord*)start, (HeapWord*)end);
}
//
// Map the closed and open archive heap objects to the runtime java heap.
//
// The shared objects are mapped at (or close to ) the java heap top in
// closed archive regions. The mapped objects contain no out-going
// references to any other java heap regions. GC does not write into the
// mapped closed archive heap region.
//
// The open archive heap objects are mapped below the shared objects in
// the runtime java heap. The mapped open archive heap data only contains
// references to the shared objects and open archive objects initially.
// During runtime execution, out-going references to any other java heap
// regions may be added. GC may mark and update references in the mapped
// open archive objects.
void FileMapInfo::map_heap_regions_impl() {
if (!HeapShared::is_heap_object_archiving_allowed()) {
log_info(cds)("CDS heap data is being ignored. UseG1GC, "
"UseCompressedOops and UseCompressedClassPointers are required.");
return;
}
if (JvmtiExport::should_post_class_file_load_hook() && JvmtiExport::has_early_class_hook_env()) {
ShouldNotReachHere(); // CDS should have been disabled.
// The archived objects are mapped at JVM start-up, but we don't know if
// j.l.String or j.l.Class might be replaced by the ClassFileLoadHook,
// which would make the archived String or mirror objects invalid. Let's be safe and not
// use the archived objects. These 2 classes are loaded during the JVMTI "early" stage.
//
// If JvmtiExport::has_early_class_hook_env() is false, the classes of some objects
// in the archived subgraphs may be replaced by the ClassFileLoadHook. But that's OK
// because we won't install an archived object subgraph if the klass of any of the
// referenced objects are replaced. See HeapShared::initialize_from_archived_subgraph().
}
MemRegion heap_reserved = Universe::heap()->reserved_region();
log_info(cds)("CDS archive was created with max heap size = " SIZE_FORMAT "M, and the following configuration:",
max_heap_size()/M);
log_info(cds)(" narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
p2i(narrow_klass_base()), narrow_klass_shift());
log_info(cds)(" narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d",
narrow_oop_mode(), p2i(narrow_oop_base()), narrow_oop_shift());
log_info(cds)("The current max heap size = " SIZE_FORMAT "M, HeapRegion::GrainBytes = " SIZE_FORMAT,
heap_reserved.byte_size()/M, HeapRegion::GrainBytes);
log_info(cds)(" narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
p2i(CompressedKlassPointers::base()), CompressedKlassPointers::shift());
log_info(cds)(" narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d",
CompressedOops::mode(), p2i(CompressedOops::base()), CompressedOops::shift());
if (narrow_klass_base() != CompressedKlassPointers::base() ||
narrow_klass_shift() != CompressedKlassPointers::shift()) {
log_info(cds)("CDS heap data cannot be used because the archive was created with an incompatible narrow klass encoding mode.");
return;
}
if (narrow_oop_mode() != CompressedOops::mode() ||
narrow_oop_base() != CompressedOops::base() ||
narrow_oop_shift() != CompressedOops::shift()) {
log_info(cds)("CDS heap data need to be relocated because the archive was created with an incompatible oop encoding mode.");
_heap_pointers_need_patching = true;
} else {
MemRegion range = get_heap_regions_range_with_current_oop_encoding_mode();
if (!heap_reserved.contains(range)) {
log_info(cds)("CDS heap data need to be relocated because");
log_info(cds)("the desired range " PTR_FORMAT " - " PTR_FORMAT, p2i(range.start()), p2i(range.end()));
log_info(cds)("is outside of the heap " PTR_FORMAT " - " PTR_FORMAT, p2i(heap_reserved.start()), p2i(heap_reserved.end()));
_heap_pointers_need_patching = true;
}
}
ptrdiff_t delta = 0;
if (_heap_pointers_need_patching) {
// dumptime heap end ------------v
// [ |archived heap regions| ] runtime heap end ------v
// [ |archived heap regions| ]
// |<-----delta-------------------->|
//
// At dump time, the archived heap regions were near the top of the heap.
// At run time, they may not be inside the heap, so we move them so
// that they are now near the top of the runtime time. This can be done by
// the simple math of adding the delta as shown above.
address dumptime_heap_end = (address)_header->_heap_reserved.end();
address runtime_heap_end = (address)heap_reserved.end();
delta = runtime_heap_end - dumptime_heap_end;
}
log_info(cds)("CDS heap data relocation delta = " INTX_FORMAT " bytes", delta);
HeapShared::init_narrow_oop_decoding(narrow_oop_base() + delta, narrow_oop_shift());
CDSFileMapRegion* si = space_at(MetaspaceShared::first_closed_archive_heap_region);
address relocated_closed_heap_region_bottom = start_address_as_decoded_from_archive(si);
if (!is_aligned(relocated_closed_heap_region_bottom, HeapRegion::GrainBytes)) {
// Align the bottom of the closed archive heap regions at G1 region boundary.
// This will avoid the situation where the highest open region and the lowest
// closed region sharing the same G1 region. Otherwise we will fail to map the
// open regions.
size_t align = size_t(relocated_closed_heap_region_bottom) % HeapRegion::GrainBytes;
delta -= align;
log_info(cds)("CDS heap data need to be relocated lower by a further " SIZE_FORMAT
" bytes to " INTX_FORMAT " to be aligned with HeapRegion::GrainBytes",
align, delta);
HeapShared::init_narrow_oop_decoding(narrow_oop_base() + delta, narrow_oop_shift());
_heap_pointers_need_patching = true;
relocated_closed_heap_region_bottom = start_address_as_decoded_from_archive(si);
}
assert(is_aligned(relocated_closed_heap_region_bottom, HeapRegion::GrainBytes),
"must be");
// Map the closed_archive_heap regions, GC does not write into the regions.
if (map_heap_data(&closed_archive_heap_ranges,
MetaspaceShared::first_closed_archive_heap_region,
MetaspaceShared::max_closed_archive_heap_region,
&num_closed_archive_heap_ranges)) {
HeapShared::set_closed_archive_heap_region_mapped();
// Now, map open_archive heap regions, GC can write into the regions.
if (map_heap_data(&open_archive_heap_ranges,
MetaspaceShared::first_open_archive_heap_region,
MetaspaceShared::max_open_archive_heap_region,
&num_open_archive_heap_ranges,
true /* open */)) {
HeapShared::set_open_archive_heap_region_mapped();
}
}
}
void FileMapInfo::map_heap_regions() {
if (has_heap_regions()) {
map_heap_regions_impl();
}
if (!HeapShared::closed_archive_heap_region_mapped()) {
assert(closed_archive_heap_ranges == NULL &&
num_closed_archive_heap_ranges == 0, "sanity");
}
if (!HeapShared::open_archive_heap_region_mapped()) {
assert(open_archive_heap_ranges == NULL && num_open_archive_heap_ranges == 0, "sanity");
}
}
bool FileMapInfo::map_heap_data(MemRegion **heap_mem, int first,
int max, int* num, bool is_open_archive) {
MemRegion * regions = new MemRegion[max];
CDSFileMapRegion* si;
int region_num = 0;
for (int i = first;
i < first + max; i++) {
si = space_at(i);
size_t size = si->_used;
if (size > 0) {
HeapWord* start = (HeapWord*)start_address_as_decoded_from_archive(si);
regions[region_num] = MemRegion(start, size / HeapWordSize);
region_num ++;
log_info(cds)("Trying to map heap data: region[%d] at " INTPTR_FORMAT ", size = " SIZE_FORMAT_W(8) " bytes",
i, p2i(start), size);
}
}
if (region_num == 0) {
return false; // no archived java heap data
}
// Check that ranges are within the java heap
if (!G1CollectedHeap::heap()->check_archive_addresses(regions, region_num)) {
log_info(cds)("UseSharedSpaces: Unable to allocate region, range is not within java heap.");
return false;
}
// allocate from java heap
if (!G1CollectedHeap::heap()->alloc_archive_regions(
regions, region_num, is_open_archive)) {
log_info(cds)("UseSharedSpaces: Unable to allocate region, java heap range is already in use.");
return false;
}
// Map the archived heap data. No need to call MemTracker::record_virtual_memory_type()
// for mapped regions as they are part of the reserved java heap, which is
// already recorded.
for (int i = 0; i < region_num; i++) {
si = space_at(first + i);
char* addr = (char*)regions[i].start();
char* base = os::map_memory(_fd, _full_path, si->_file_offset,
addr, regions[i].byte_size(), si->_read_only,
si->_allow_exec);
if (base == NULL || base != addr) {
// dealloc the regions from java heap
dealloc_archive_heap_regions(regions, region_num, is_open_archive);
log_info(cds)("UseSharedSpaces: Unable to map at required address in java heap. "
INTPTR_FORMAT ", size = " SIZE_FORMAT " bytes",
p2i(addr), regions[i].byte_size());
return false;
}
if (VerifySharedSpaces && !region_crc_check(addr, regions[i].byte_size(), si->_crc)) {
// dealloc the regions from java heap
dealloc_archive_heap_regions(regions, region_num, is_open_archive);
log_info(cds)("UseSharedSpaces: mapped heap regions are corrupt");
return false;
}
}
// the shared heap data is mapped successfully
*heap_mem = regions;
*num = region_num;
return true;
}
void FileMapInfo::patch_archived_heap_embedded_pointers() {
if (!_heap_pointers_need_patching) {
return;
}
patch_archived_heap_embedded_pointers(closed_archive_heap_ranges,
num_closed_archive_heap_ranges,
MetaspaceShared::first_closed_archive_heap_region);
patch_archived_heap_embedded_pointers(open_archive_heap_ranges,
num_open_archive_heap_ranges,
MetaspaceShared::first_open_archive_heap_region);
}
void FileMapInfo::patch_archived_heap_embedded_pointers(MemRegion* ranges, int num_ranges,
int first_region_idx) {
for (int i=0; i<num_ranges; i++) {
CDSFileMapRegion* si = space_at(i + first_region_idx);
HeapShared::patch_archived_heap_embedded_pointers(ranges[i], (address)si->_oopmap,
si->_oopmap_size_in_bits);
}
}
// This internally allocates objects using SystemDictionary::Object_klass(), so it
// must be called after the well-known classes are resolved.
void FileMapInfo::fixup_mapped_heap_regions() {
// If any closed regions were found, call the fill routine to make them parseable.
// Note that closed_archive_heap_ranges may be non-NULL even if no ranges were found.
if (num_closed_archive_heap_ranges != 0) {
assert(closed_archive_heap_ranges != NULL,
"Null closed_archive_heap_ranges array with non-zero count");
G1CollectedHeap::heap()->fill_archive_regions(closed_archive_heap_ranges,
num_closed_archive_heap_ranges);
}
// do the same for mapped open archive heap regions
if (num_open_archive_heap_ranges != 0) {
assert(open_archive_heap_ranges != NULL, "NULL open_archive_heap_ranges array with non-zero count");
G1CollectedHeap::heap()->fill_archive_regions(open_archive_heap_ranges,
num_open_archive_heap_ranges);
}
}
// dealloc the archive regions from java heap
void FileMapInfo::dealloc_archive_heap_regions(MemRegion* regions, int num, bool is_open) {
if (num > 0) {
assert(regions != NULL, "Null archive ranges array with non-zero count");
G1CollectedHeap::heap()->dealloc_archive_regions(regions, num, is_open);
}
}
#endif // INCLUDE_CDS_JAVA_HEAP
bool FileMapInfo::region_crc_check(char* buf, size_t size, int expected_crc) {
int crc = ClassLoader::crc32(0, buf, (jint)size);
if (crc != expected_crc) {
fail_continue("Checksum verification failed.");
return false;
}
return true;
}
bool FileMapInfo::verify_region_checksum(int i) {
assert(VerifySharedSpaces, "sanity");
size_t sz = space_at(i)->_used;
if (sz == 0) {
return true; // no data
}
return region_crc_check(region_addr(i), sz, space_at(i)->_crc);
}
void FileMapInfo::unmap_regions(int regions[], char* saved_base[], size_t len) {
for (int i = 0; i < (int)len; i++) {
if (saved_base[i] != NULL) {
unmap_region(regions[i]);
}
}
}
// Unmap a memory region in the address space.
void FileMapInfo::unmap_region(int i) {
assert(!HeapShared::is_heap_region(i), "sanity");
CDSFileMapRegion* si = space_at(i);
size_t used = si->_used;
size_t size = align_up(used, os::vm_allocation_granularity());
if (used == 0) {
return;
}
char* addr = region_addr(i);
if (!os::unmap_memory(addr, size)) {
fail_stop("Unable to unmap shared space.");
}
}
void FileMapInfo::assert_mark(bool check) {
if (!check) {
fail_stop("Mark mismatch while restoring from shared file.");
}
}
void FileMapInfo::metaspace_pointers_do(MetaspaceClosure* it) {
_shared_path_table.metaspace_pointers_do(it);
}
FileMapInfo* FileMapInfo::_current_info = NULL;
FileMapInfo* FileMapInfo::_dynamic_archive_info = NULL;
bool FileMapInfo::_heap_pointers_need_patching = false;
SharedPathTable FileMapInfo::_shared_path_table;
bool FileMapInfo::_validating_shared_path_table = false;
bool FileMapInfo::_memory_mapping_failed = false;
// Open the shared archive file, read and validate the header
// information (version, boot classpath, etc.). If initialization
// fails, shared spaces are disabled and the file is closed. [See
// fail_continue.]
//
// Validation of the archive is done in two steps:
//
// [1] validate_header() - done here. This checks the header, including _paths_misc_info.
// [2] validate_shared_path_table - this is done later, because the table is in the RW
// region of the archive, which is not mapped yet.
bool FileMapInfo::initialize(bool is_static) {
assert(UseSharedSpaces, "UseSharedSpaces expected.");
if (JvmtiExport::should_post_class_file_load_hook() && JvmtiExport::has_early_class_hook_env()) {
// CDS assumes that no classes resolved in SystemDictionary::resolve_well_known_classes
// are replaced at runtime by JVMTI ClassFileLoadHook. All of those classes are resolved
// during the JVMTI "early" stage, so we can still use CDS if
// JvmtiExport::has_early_class_hook_env() is false.
FileMapInfo::fail_continue("CDS is disabled because early JVMTI ClassFileLoadHook is in use.");
return false;
}
if (!open_for_read()) {
return false;
}
init_from_file(_fd, is_static);
// UseSharedSpaces could be disabled if the checking of some of the header fields in
// init_from_file has failed.
if (!UseSharedSpaces || !validate_header(is_static)) {
return false;
}
return true;
}
char* FileMapInfo::region_addr(int idx) {
CDSFileMapRegion* si = space_at(idx);
if (HeapShared::is_heap_region(idx)) {
assert(DumpSharedSpaces, "The following doesn't work at runtime");
return si->_used > 0 ?
(char*)start_address_as_decoded_with_current_oop_encoding_mode(si) : NULL;
} else {
return si->_addr._base;
}
}
int FileMapHeader::compute_crc() {
char* start = (char*)this;
// start computing from the field after _crc
char* buf = (char*)&_crc + sizeof(_crc);
size_t sz = _header_size - (buf - start);
int crc = ClassLoader::crc32(0, buf, (jint)sz);
return crc;
}
// This function should only be called during run time with UseSharedSpaces enabled.
bool FileMapHeader::validate() {
if (_obj_alignment != ObjectAlignmentInBytes) {
FileMapInfo::fail_continue("The shared archive file's ObjectAlignmentInBytes of %d"
" does not equal the current ObjectAlignmentInBytes of " INTX_FORMAT ".",
_obj_alignment, ObjectAlignmentInBytes);
return false;
}
if (_compact_strings != CompactStrings) {
FileMapInfo::fail_continue("The shared archive file's CompactStrings setting (%s)"
" does not equal the current CompactStrings setting (%s).",
_compact_strings ? "enabled" : "disabled",
CompactStrings ? "enabled" : "disabled");
return false;
}
// This must be done after header validation because it might change the
// header data
const char* prop = Arguments::get_property("java.system.class.loader");
if (prop != NULL) {
warning("Archived non-system classes are disabled because the "
"java.system.class.loader property is specified (value = \"%s\"). "
"To use archived non-system classes, this property must not be set", prop);
_has_platform_or_app_classes = false;
}
// For backwards compatibility, we don't check the verification setting
// if the archive only contains system classes.
if (_has_platform_or_app_classes &&
((!_verify_local && BytecodeVerificationLocal) ||
(!_verify_remote && BytecodeVerificationRemote))) {
FileMapInfo::fail_continue("The shared archive file was created with less restrictive "
"verification setting than the current setting.");
return false;
}
// Java agents are allowed during run time. Therefore, the following condition is not
// checked: (!_allow_archiving_with_java_agent && AllowArchivingWithJavaAgent)
// Note: _allow_archiving_with_java_agent is set in the shared archive during dump time
// while AllowArchivingWithJavaAgent is set during the current run.
if (_allow_archiving_with_java_agent && !AllowArchivingWithJavaAgent) {
FileMapInfo::fail_continue("The setting of the AllowArchivingWithJavaAgent is different "
"from the setting in the shared archive.");
return false;
}
if (_allow_archiving_with_java_agent) {
warning("This archive was created with AllowArchivingWithJavaAgent. It should be used "
"for testing purposes only and should not be used in a production environment");
}
return true;
}
bool FileMapInfo::validate_header(bool is_static) {
bool status = _header->validate();
if (status) {
if (!ClassLoader::check_shared_paths_misc_info(_paths_misc_info, _header->_paths_misc_info_size, is_static)) {
if (!PrintSharedArchiveAndExit) {
fail_continue("shared class paths mismatch (hint: enable -Xlog:class+path=info to diagnose the failure)");
status = false;
}
}
}
if (_paths_misc_info != NULL) {
FREE_C_HEAP_ARRAY(char, _paths_misc_info);
_paths_misc_info = NULL;
}
return status;
}
// Check if a given address is within one of the shared regions
bool FileMapInfo::is_in_shared_region(const void* p, int idx) {
assert(idx == MetaspaceShared::ro ||
idx == MetaspaceShared::rw ||
idx == MetaspaceShared::mc ||
idx == MetaspaceShared::md, "invalid region index");
char* base = region_addr(idx);
if (p >= base && p < base + space_at(idx)->_used) {
return true;
}
return false;
}
// Unmap mapped regions of shared space.
void FileMapInfo::stop_sharing_and_unmap(const char* msg) {
MetaspaceShared::set_shared_metaspace_range(NULL, NULL);
FileMapInfo *map_info = FileMapInfo::current_info();
if (map_info) {
map_info->fail_continue("%s", msg);
for (int i = 0; i < MetaspaceShared::num_non_heap_spaces; i++) {
if (!HeapShared::is_heap_region(i)) {
char *addr = map_info->region_addr(i);
if (addr != NULL) {
map_info->unmap_region(i);
map_info->space_at(i)->_addr._base = NULL;
}
}
}
// Dealloc the archive heap regions only without unmapping. The regions are part
// of the java heap. Unmapping of the heap regions are managed by GC.
map_info->dealloc_archive_heap_regions(open_archive_heap_ranges,
num_open_archive_heap_ranges,
true);
map_info->dealloc_archive_heap_regions(closed_archive_heap_ranges,
num_closed_archive_heap_ranges,
false);
} else if (DumpSharedSpaces) {
fail_stop("%s", msg);
}
}
#if INCLUDE_JVMTI
ClassPathEntry** FileMapInfo::_classpath_entries_for_jvmti = NULL;
ClassPathEntry* FileMapInfo::get_classpath_entry_for_jvmti(int i, TRAPS) {
ClassPathEntry* ent = _classpath_entries_for_jvmti[i];
if (ent == NULL) {
if (i == 0) {
ent = ClassLoader:: get_jrt_entry();
assert(ent != NULL, "must be");
} else {
SharedClassPathEntry* scpe = shared_path(i);
assert(scpe->is_jar(), "must be"); // other types of scpe will not produce archived classes
const char* path = scpe->name();
struct stat st;
if (os::stat(path, &st) != 0) {
char *msg = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, strlen(path) + 128); ;
jio_snprintf(msg, strlen(path) + 127, "error in opening JAR file %s", path);
THROW_MSG_(vmSymbols::java_io_IOException(), msg, NULL);
} else {
ent = ClassLoader::create_class_path_entry(path, &st, /*throw_exception=*/true, false, false, CHECK_NULL);
}
}
MutexLocker mu(CDSClassFileStream_lock, THREAD);
if (_classpath_entries_for_jvmti[i] == NULL) {
_classpath_entries_for_jvmti[i] = ent;
} else {
// Another thread has beat me to creating this entry
delete ent;
ent = _classpath_entries_for_jvmti[i];
}
}
return ent;
}
ClassFileStream* FileMapInfo::open_stream_for_jvmti(InstanceKlass* ik, Handle class_loader, TRAPS) {
int path_index = ik->shared_classpath_index();
assert(path_index >= 0, "should be called for shared built-in classes only");
assert(path_index < (int)get_number_of_shared_paths(), "sanity");
ClassPathEntry* cpe = get_classpath_entry_for_jvmti(path_index, CHECK_NULL);
assert(cpe != NULL, "must be");
Symbol* name = ik->name();
const char* const class_name = name->as_C_string();
const char* const file_name = ClassLoader::file_name_for_class_name(class_name,
name->utf8_length());
ClassLoaderData* loader_data = ClassLoaderData::class_loader_data(class_loader());
ClassFileStream* cfs = cpe->open_stream_for_loader(file_name, loader_data, THREAD);
assert(cfs != NULL, "must be able to read the classfile data of shared classes for built-in loaders.");
log_debug(cds, jvmti)("classfile data for %s [%d: %s] = %d bytes", class_name, path_index,
cfs->source(), cfs->length());
return cfs;
}
#endif