JDK14/Java14源码在线阅读
/*
* 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/archiveUtils.inline.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/bitMap.inline.hpp"
#include "utilities/classpathStream.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
// 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 (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);
}
}
}
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->set_header_size(header_size);
_header->set_version(INVALID_CDS_ARCHIVE_VERSION);
_header->set_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_shift = CompressedKlassPointers::shift();
if (HeapShared::is_heap_object_archiving_allowed()) {
_heap_end = CompressedOops::end();
}
// 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);
_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();
_requested_base_address = (char*)SharedBaseAddress;
_mapped_base_address = (char*)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;
if (!DynamicDumpSharedSpaces) {
set_shared_path_table(mapinfo->_shared_path_table);
}
}
void SharedClassPathEntry::init_as_non_existent(const char* path, TRAPS) {
_type = non_existent_entry;
set_name(path, THREAD);
}
void SharedClassPathEntry::init(bool is_modules_image,
ClassPathEntry* cpe, TRAPS) {
Arguments::assert_is_dumping_archive();
_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());
}
// No need to save the name of the module file, as it will be computed at run time
// to allow relocation of the JDK directory.
const char* name = is_modules_image ? "" : cpe->name();
set_name(name, THREAD);
}
void SharedClassPathEntry::set_name(const char* name, TRAPS) {
size_t len = strlen(name) + 1;
_name = MetadataFactory::new_array<char>(ClassLoaderData::the_null_class_loader_data(), (int)len, THREAD);
strcpy(_name->data(), name);
}
const char* SharedClassPathEntry::name() const {
if (UseSharedSpaces && is_modules_image()) {
// 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.
return ClassLoader::get_jrt_entry()->name();
} else {
return _name->data();
}
}
bool SharedClassPathEntry::validate(bool is_class_path) const {
assert(UseSharedSpaces, "runtime only");
struct stat st;
const char* 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;
}
bool SharedClassPathEntry::check_non_existent() const {
assert(_type == non_existent_entry, "must be");
log_info(class, path)("should be non-existent: %s", name());
struct stat st;
if (os::stat(name(), &st) != 0) {
log_info(class, path)("ok");
return true; // file doesn't exist
} else {
return false;
}
}
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_entries = 0;
num_entries += ClassLoader::num_boot_classpath_entries();
num_entries += ClassLoader::num_app_classpath_entries();
num_entries += ClassLoader::num_module_path_entries();
num_entries += FileMapInfo::num_non_existent_class_paths();
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() {
Arguments::assert_is_dumping_archive();
EXCEPTION_MARK; // The following calls should never throw, but would exit VM on error.
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;
i = add_shared_classpaths(i, "boot", jrt, THREAD);
i = add_shared_classpaths(i, "app", ClassLoader::app_classpath_entries(), THREAD);
i = add_shared_classpaths(i, "module", ClassLoader::module_path_entries(), THREAD);
for (int x = 0; x < num_non_existent_class_paths(); x++, i++) {
const char* path = _non_existent_class_paths->at(x);
shared_path(i)->init_as_non_existent(path, THREAD);
}
assert(i == _shared_path_table.size(), "number of shared path entry mismatch");
}
int FileMapInfo::add_shared_classpaths(int i, const char* which, ClassPathEntry *cpe, TRAPS) {
while (cpe != NULL) {
bool is_jrt = (cpe == ClassLoader::get_jrt_entry());
const char* type = (is_jrt ? "jrt" : (cpe->is_jar_file() ? "jar" : "dir"));
log_info(class, path)("add %s shared path (%s) %s", which, type, cpe->name());
SharedClassPathEntry* ent = shared_path(i);
ent->init(is_jrt, cpe, THREAD);
if (cpe->is_jar_file()) {
update_jar_manifest(cpe, ent, THREAD);
}
if (is_jrt) {
cpe = ClassLoader::get_next_boot_classpath_entry(cpe);
} else {
cpe = cpe->next();
}
i++;
}
return i;
}
void FileMapInfo::check_nonempty_dir_in_shared_path_table() {
Arguments::assert_is_dumping_archive();
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)) {
log_error(cds)("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);
}
}
void FileMapInfo::record_non_existent_class_path_entry(const char* path) {
Arguments::assert_is_dumping_archive();
log_info(class, path)("non-existent Class-Path entry %s", path);
if (_non_existent_class_paths == NULL) {
_non_existent_class_paths = new (ResourceObj::C_HEAP, mtInternal)GrowableArray<const char*>(10, true);
}
_non_existent_class_paths->append(os::strdup(path));
}
int FileMapInfo::num_non_existent_class_paths() {
Arguments::assert_is_dumping_archive();
if (_non_existent_class_paths != NULL) {
return _non_existent_class_paths->length();
} else {
return 0;
}
}
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_jar_manifest(ClassPathEntry *cpe, SharedClassPathEntry* ent, TRAPS) {
ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
ResourceMark rm(THREAD);
jint manifest_size;
assert(cpe->is_jar_file() && 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<const char*>* FileMapInfo::create_path_array(const char* paths) {
GrowableArray<const char*>* path_array = new(ResourceObj::RESOURCE_AREA, mtInternal)
GrowableArray<const char*>(10);
ClasspathStream cp_stream(paths);
while (cp_stream.has_next()) {
const char* path = cp_stream.get_next();
struct stat st;
if (os::stat(path, &st) == 0) {
path_array->append(path);
}
}
return path_array;
}
bool FileMapInfo::classpath_failure(const char* msg, const char* name) {
ClassLoader::trace_class_path(msg, name);
if (PrintSharedArchiveAndExit) {
MetaspaceShared::set_archive_loading_failed();
}
return false;
}
bool FileMapInfo::check_paths(int shared_path_start_idx, int num_paths, GrowableArray<const 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<const 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 classpath_failure("[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 classpath_failure("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<const char*>* rp_array = create_path_array(appcp);
if (rp_array->length() == 0) {
// None of the jar file specified in the runtime -cp exists.
return classpath_failure("None of the jar file specified in the runtime -cp exists: -Djava.class.path=", appcp);
}
// Handling of non-existent entries in the classpath: we eliminate all the non-existent
// entries from both the dump time classpath (ClassLoader::update_class_path_entry_list)
// and the runtime classpath (FileMapInfo::create_path_array), and check the remaining
// entries. E.g.:
//
// dump : -cp a.jar:NE1:NE2:b.jar -> a.jar:b.jar -> recorded in archive.
// run 1: -cp NE3:a.jar:NE4:b.jar -> a.jar:b.jar -> matched
// run 2: -cp x.jar:NE4:b.jar -> x.jar:b.jar -> mismatched
int j = header()->app_class_paths_start_index();
mismatch = check_paths(j, shared_app_paths_len, rp_array);
if (mismatch) {
return classpath_failure("[APP classpath mismatch, actual: -Djava.class.path=", appcp);
}
}
return true;
}
void FileMapInfo::log_paths(const char* msg, int start_idx, int end_idx) {
LogTarget(Info, class, path) lt;
if (lt.is_enabled()) {
LogStream ls(lt);
ls.print("%s", msg);
const char* prefix = "";
for (int i = start_idx; i < end_idx; i++) {
ls.print("%s%s", prefix, shared_path(i)->name());
prefix = os::path_separator();
}
ls.cr();
}
}
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");
}
}
log_paths("Expecting BOOT path=", 0, header()->app_class_paths_start_index());
log_paths("Expecting -Djava.class.path=", header()->app_class_paths_start_index(), header()->app_module_paths_start_index());
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;
}
}
validate_non_existent_class_paths();
_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;
}
void FileMapInfo::validate_non_existent_class_paths() {
// All of the recorded non-existent paths came from the Class-Path: attribute from the JAR
// files on the app classpath. If any of these are found to exist during runtime,
// it will change how classes are loading for the app loader. For safety, disable
// loading of archived platform/app classes (currently there's no way to disable just the
// app classes).
assert(UseSharedSpaces, "runtime only");
for (int i = header()->app_module_paths_start_index() + header()->num_module_paths();
i < get_number_of_shared_paths();
i++) {
SharedClassPathEntry* ent = shared_path(i);
if (!ent->check_non_existent()) {
warning("Archived non-system classes are disabled because the "
"file %s exists", ent->name());
header()->set_has_platform_or_app_classes(false);
}
}
}
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 {
// 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) {
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;
}
const char* actual_ident = header()->jvm_ident();
if (actual_ident[JVM_IDENT_MAX-1] != 0) {
FileMapInfo::fail_continue("JVM version identifier is corrupted.");
return false;
}
char expected_ident[JVM_IDENT_MAX];
get_header_version(expected_ident);
if (strncmp(actual_ident, expected_ident, JVM_IDENT_MAX-1) != 0) {
log_info(cds)("_jvm_ident expected: %s", expected_ident);
log_info(cds)(" actual: %s", actual_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 + 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);
FileMapRegion* 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;
}
}
return true;
}
void FileMapInfo::seek_to_position(size_t pos) {
if (lseek(_fd, (long)pos, SEEK_SET) < 0) {
fail_stop("Unable to seek to position " SIZE_FORMAT, pos);
}
}
// Read the FileMapInfo information from the file.
bool FileMapInfo::open_for_read() {
if (_file_open) {
return true;
}
if (is_static()) {
_full_path = Arguments::GetSharedArchivePath();
} else {
_full_path = Arguments::GetSharedDynamicArchivePath();
}
int fd = os::open(_full_path, O_RDONLY | O_BINARY, 0);
if (fd < 0) {
if (errno == ENOENT) {
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_open = true;
// Seek past the header. We will write the header after all regions are written
// and their CRCs computed.
size_t header_bytes = header()->header_size();
if (header()->magic() == CDS_DYNAMIC_ARCHIVE_MAGIC) {
header_bytes += strlen(Arguments::GetSharedArchivePath()) + 1;
}
header_bytes = align_up(header_bytes, os::vm_allocation_granularity());
_file_offset = header_bytes;
seek_to_position(_file_offset);
}
// Write the header to the file, seek to the next allocation boundary.
void FileMapInfo::write_header() {
_file_offset = 0;
seek_to_position(_file_offset);
char* base_archive_name = NULL;
if (header()->magic() == CDS_DYNAMIC_ARCHIVE_MAGIC) {
base_archive_name = (char*)Arguments::GetSharedArchivePath();
header()->set_base_archive_name_size(strlen(base_archive_name) + 1);
header()->set_base_archive_is_default(FLAG_IS_DEFAULT(SharedArchiveFile));
}
assert(is_file_position_aligned(), "must be");
write_bytes(header(), header()->header_size());
if (base_archive_name != NULL) {
write_bytes(base_archive_name, header()->base_archive_name_size());
}
}
size_t FileMapRegion::used_aligned() const {
return align_up(used(), os::vm_allocation_granularity());
}
void FileMapRegion::init(int region_index, char* base, size_t size, bool read_only,
bool allow_exec, int crc) {
_is_heap_region = HeapShared::is_heap_region(region_index);
_is_bitmap_region = (region_index == MetaspaceShared::bm);
_mapping_offset = 0;
if (_is_heap_region) {
assert(!DynamicDumpSharedSpaces, "must be");
assert((base - (char*)CompressedKlassPointers::base()) % HeapWordSize == 0, "Sanity");
if (base != NULL) {
_mapping_offset = (size_t)CompressedOops::encode_not_null((oop)base);
assert(_mapping_offset == (size_t)(uint32_t)_mapping_offset, "must be 32-bit only");
}
} else {
if (base != NULL) {
assert(base >= (char*)SharedBaseAddress, "must be");
_mapping_offset = base - (char*)SharedBaseAddress;
}
}
_used = size;
_read_only = read_only;
_allow_exec = allow_exec;
_crc = crc;
_mapped_from_file = false;
_mapped_base = NULL;
}
void FileMapInfo::write_region(int region, char* base, size_t size,
bool read_only, bool allow_exec) {
Arguments::assert_is_dumping_archive();
FileMapRegion* si = space_at(region);
char* target_base;
if (region == MetaspaceShared::bm) {
target_base = NULL; // always NULL for bm region.
} else {
if (DynamicDumpSharedSpaces) {
assert(!HeapShared::is_heap_region(region), "dynamic archive doesn't support heap regions");
target_base = DynamicArchive::buffer_to_target(base);
} else {
target_base = base;
}
}
si->set_file_offset(_file_offset);
char* requested_base = (target_base == NULL) ? NULL : target_base + MetaspaceShared::final_delta();
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(requested_base), _file_offset);
int crc = ClassLoader::crc32(0, base, (jint)size);
si->init(region, target_base, size, read_only, allow_exec, crc);
if (base != NULL) {
write_bytes_aligned(base, size);
}
}
void FileMapInfo::write_bitmap_region(const CHeapBitMap* ptrmap) {
ResourceMark rm;
size_t size_in_bits = ptrmap->size();
size_t size_in_bytes = ptrmap->size_in_bytes();
uintptr_t* buffer = (uintptr_t*)NEW_RESOURCE_ARRAY(char, size_in_bytes);
ptrmap->write_to(buffer, size_in_bytes);
header()->set_ptrmap_size_in_bits(size_in_bits);
log_info(cds)("ptrmap = " INTPTR_FORMAT " (" SIZE_FORMAT " bytes)",
p2i(buffer), size_in_bytes);
write_region(MetaspaceShared::bm, (char*)buffer, size_in_bytes, /*read_only=*/true, /*allow_exec=*/false);
}
// 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) {
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;
}
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) {
address oopmap = oopmaps->at(arr_idx)._oopmap;
assert(oopmap >= (address)SharedBaseAddress, "must be");
space_at(i)->init_oopmap(oopmap - (address)SharedBaseAddress,
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) {
assert(_file_open, "must be");
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() {
assert(_file_open, "must be");
size_t new_file_offset = align_up(_file_offset,
os::vm_allocation_granularity());
if (new_file_offset != _file_offset) {
_file_offset = new_file_offset;
// Seek one byte back from the target and write a byte to insure
// that the written file is the correct length.
_file_offset -= 1;
seek_to_position(_file_offset);
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();
}
void FileMapInfo::set_final_requested_base(char* b) {
header()->set_final_requested_base(b);
}
// 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;
FileMapRegion* 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->set_read_only(false);
return true;
}
// Memory map a region in the address space.
static const char* shared_region_name[] = { "MiscData", "ReadWrite", "ReadOnly", "MiscCode", "Bitmap",
"String1", "String2", "OpenArchive1", "OpenArchive2" };
MapArchiveResult FileMapInfo::map_regions(int regions[], int num_regions, char* mapped_base_address, ReservedSpace rs) {
DEBUG_ONLY(FileMapRegion* last_region = NULL);
intx addr_delta = mapped_base_address - header()->requested_base_address();
// Make sure we don't attempt to use header()->mapped_base_address() unless
// it's been successfully mapped.
DEBUG_ONLY(header()->set_mapped_base_address((char*)(uintptr_t)0xdeadbeef);)
for (int r = 0; r < num_regions; r++) {
int idx = regions[r];
MapArchiveResult result = map_region(idx, addr_delta, mapped_base_address, rs);
if (result != MAP_ARCHIVE_SUCCESS) {
return result;
}
FileMapRegion* si = space_at(idx);
DEBUG_ONLY(if (last_region != NULL) {
// Ensure that the OS won't be able to allocate new memory spaces between any mapped
// regions, or else it would mess up the simple comparision in MetaspaceObj::is_shared().
assert(si->mapped_base() == last_region->mapped_end(), "must have no gaps");
}
last_region = si;)
log_info(cds)("Mapped %s region #%d at base " INTPTR_FORMAT " top " INTPTR_FORMAT " (%s)", is_static() ? "static " : "dynamic",
idx, p2i(si->mapped_base()), p2i(si->mapped_end()),
shared_region_name[idx]);
}
header()->set_mapped_base_address(header()->requested_base_address() + addr_delta);
if (addr_delta != 0 && !relocate_pointers(addr_delta)) {
return MAP_ARCHIVE_OTHER_FAILURE;
}
return MAP_ARCHIVE_SUCCESS;
}
bool FileMapInfo::read_region(int i, char* base, size_t size) {
assert(MetaspaceShared::use_windows_memory_mapping(), "used by windows only");
FileMapRegion* si = space_at(i);
log_info(cds)("Commit %s region #%d at base " INTPTR_FORMAT " top " INTPTR_FORMAT " (%s)%s",
is_static() ? "static " : "dynamic", i, p2i(base), p2i(base + size),
shared_region_name[i], si->allow_exec() ? " exec" : "");
if (!os::commit_memory(base, size, si->allow_exec())) {
log_error(cds)("Failed to commit %s region #%d (%s)", is_static() ? "static " : "dynamic",
i, shared_region_name[i]);
return false;
}
if (lseek(_fd, (long)si->file_offset(), SEEK_SET) != (int)si->file_offset() ||
read_bytes(base, size) != size) {
return false;
}
return true;
}
MapArchiveResult FileMapInfo::map_region(int i, intx addr_delta, char* mapped_base_address, ReservedSpace rs) {
assert(!HeapShared::is_heap_region(i), "sanity");
FileMapRegion* si = space_at(i);
size_t size = si->used_aligned();
char *requested_addr = mapped_base_address + si->mapping_offset();
assert(si->mapped_base() == NULL, "must be not mapped yet");
assert(requested_addr != NULL, "must be specified");
si->set_mapped_from_file(false);
if (MetaspaceShared::use_windows_memory_mapping()) {
// 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->set_read_only(false);
} else if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space() ||
Arguments::has_jfr_option()) {
// If a tool agent is in use (debugging enabled), or JFR, we must map the address space RW
si->set_read_only(false);
} else if (addr_delta != 0) {
si->set_read_only(false); // Need to patch the pointers
}
if (rs.is_reserved()) {
assert(rs.contains(requested_addr) && rs.contains(requested_addr + size - 1), "must be");
MemTracker::record_virtual_memory_type((address)requested_addr, mtClassShared);
}
if (MetaspaceShared::use_windows_memory_mapping() && rs.is_reserved()) {
// This is the second time we try to map the archive(s). We have already created a ReservedSpace
// that covers all the FileMapRegions to ensure all regions can be mapped. However, Windows
// can't mmap into a ReservedSpace, so we just os::read() the data. We're going to patch all the
// regions anyway, so there's no benefit for mmap anyway.
if (!read_region(i, requested_addr, size)) {
log_info(cds)("Failed to read %s shared space into reserved space at " INTPTR_FORMAT,
shared_region_name[i], p2i(requested_addr));
return MAP_ARCHIVE_OTHER_FAILURE; // oom or I/O error.
}
} else {
char* base = os::map_memory(_fd, _full_path, si->file_offset(),
requested_addr, size, si->read_only(),
si->allow_exec());
if (base != requested_addr) {
log_info(cds)("Unable to map %s shared space at " INTPTR_FORMAT,
shared_region_name[i], p2i(requested_addr));
_memory_mapping_failed = true;
return MAP_ARCHIVE_MMAP_FAILURE;
}
si->set_mapped_from_file(true);
}
si->set_mapped_base(requested_addr);
if (!rs.is_reserved()) {
// When mapping on Windows for the first attempt, we don't reserve the address space for the regions
// (Windows can't mmap into a ReservedSpace). In this case, NMT requires we call it after
// os::map_memory has succeeded.
assert(MetaspaceShared::use_windows_memory_mapping(), "Windows memory mapping only");
MemTracker::record_virtual_memory_type((address)requested_addr, mtClassShared);
}
if (VerifySharedSpaces && !verify_region_checksum(i)) {
return MAP_ARCHIVE_OTHER_FAILURE;
}
return MAP_ARCHIVE_SUCCESS;
}
char* FileMapInfo::map_relocation_bitmap(size_t& bitmap_size) {
FileMapRegion* si = space_at(MetaspaceShared::bm);
bitmap_size = si->used_aligned();
bool read_only = true, allow_exec = false;
char* requested_addr = NULL; // allow OS to pick any location
char* bitmap_base = os::map_memory(_fd, _full_path, si->file_offset(),
requested_addr, bitmap_size, read_only, allow_exec);
if (bitmap_base == NULL) {
log_error(cds)("failed to map relocation bitmap");
return NULL;
}
if (VerifySharedSpaces && !region_crc_check(bitmap_base, bitmap_size, si->crc())) {
log_error(cds)("relocation bitmap CRC error");
if (!os::unmap_memory(bitmap_base, bitmap_size)) {
fatal("os::unmap_memory of relocation bitmap failed");
}
return NULL;
}
return bitmap_base;
}
bool FileMapInfo::relocate_pointers(intx addr_delta) {
log_debug(cds, reloc)("runtime archive relocation start");
size_t bitmap_size;
char* bitmap_base = map_relocation_bitmap(bitmap_size);
if (bitmap_base == NULL) {
return false;
} else {
size_t ptrmap_size_in_bits = header()->ptrmap_size_in_bits();
log_debug(cds, reloc)("mapped relocation bitmap @ " INTPTR_FORMAT " (" SIZE_FORMAT
" bytes = " SIZE_FORMAT " bits)",
p2i(bitmap_base), bitmap_size, ptrmap_size_in_bits);
BitMapView ptrmap((BitMap::bm_word_t*)bitmap_base, ptrmap_size_in_bits);
// Patch all pointers in the the mapped region that are marked by ptrmap.
address patch_base = (address)mapped_base();
address patch_end = (address)mapped_end();
// the current value of the pointers to be patched must be within this
// range (i.e., must be between the requesed base address, and the of the current archive).
// Note: top archive may point to objects in the base archive, but not the other way around.
address valid_old_base = (address)header()->requested_base_address();
address valid_old_end = valid_old_base + mapping_end_offset();
// after patching, the pointers must point inside this range
// (the requested location of the archive, as mapped at runtime).
address valid_new_base = (address)header()->mapped_base_address();
address valid_new_end = (address)mapped_end();
SharedDataRelocator<false> patcher((address*)patch_base, (address*)patch_end, valid_old_base, valid_old_end,
valid_new_base, valid_new_end, addr_delta);
ptrmap.iterate(&patcher);
if (!os::unmap_memory(bitmap_base, bitmap_size)) {
fatal("os::unmap_memory of relocation bitmap failed");
}
log_debug(cds, reloc)("runtime archive relocation done");
return true;
}
}
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(FileMapRegion* spc, bool with_current_oop_encoding_mode) {
size_t offset = spc->mapping_offset();
assert(offset == (size_t)(uint32_t)offset, "must be 32-bit only");
uint n = (uint)offset;
if (with_current_oop_encoding_mode) {
return (address)CompressedOops::decode_not_null(n);
} else {
return (address)HeapShared::decode_from_archive(n);
}
}
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 (space_at(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++) {
FileMapRegion* 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().
}
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,
MaxHeapSize/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 (!CompressedOops::is_in(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(CompressedOops::begin()), p2i(CompressedOops::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 = header()->heap_end();
address runtime_heap_end = (address)CompressedOops::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());
FileMapRegion* 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];
FileMapRegion* 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++) {
FileMapRegion* si = space_at(i + first_region_idx);
HeapShared::patch_archived_heap_embedded_pointers(ranges[i], (address)(SharedBaseAddress + si->oopmap_offset()),
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
} else {
return region_crc_check(region_addr(i), sz, space_at(i)->crc());
}
}
void FileMapInfo::unmap_regions(int regions[], int num_regions) {
for (int r = 0; r < num_regions; r++) {
int idx = regions[r];
unmap_region(idx);
}
}
// Unmap a memory region in the address space.
void FileMapInfo::unmap_region(int i) {
assert(!HeapShared::is_heap_region(i), "sanity");
FileMapRegion* si = space_at(i);
char* mapped_base = si->mapped_base();
size_t used = si->used();
size_t size = align_up(used, os::vm_allocation_granularity());
if (mapped_base != NULL && size > 0 && si->mapped_from_file()) {
log_info(cds)("Unmapping region #%d at base " INTPTR_FORMAT " (%s)", i, p2i(mapped_base),
shared_region_name[i]);
if (!os::unmap_memory(mapped_base, size)) {
fatal("os::unmap_memory failed");
}
si->set_mapped_base(NULL);
}
}
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;
GrowableArray<const char*>* FileMapInfo::_non_existent_class_paths = NULL;
// 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.
// [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() {
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