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/*
* Copyright (c) 2003, 2018, 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/classLoader.inline.hpp"
#include "classfile/classLoaderExt.hpp"
#include "classfile/compactHashtable.inline.hpp"
#include "classfile/stringTable.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/filemap.hpp"
#include "memory/metadataFactory.hpp"
#include "memory/metaspaceClosure.hpp"
#include "memory/metaspaceShared.hpp"
#include "memory/oopFactory.hpp"
#include "oops/compressedOops.inline.hpp"
#include "oops/objArrayOop.hpp"
#include "prims/jvmtiExport.hpp"
#include "runtime/arguments.hpp"
#include "runtime/java.hpp"
#include "runtime/os.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"
#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(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(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);
MetaspaceShared::set_archive_loading_failed();
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(msg, ap);
} else {
if (log_is_enabled(Info, cds)) {
ResourceMark rm;
LogStream ls(Log(cds)::info());
ls.print("UseSharedSpaces: ");
ls.vprint_cr(msg, ap);
}
}
UseSharedSpaces = false;
assert(current_info() != NULL, "singleton must be registered");
current_info()->close();
}
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);
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.
}
}
FileMapInfo::FileMapInfo() {
assert(_current_info == NULL, "must be singleton"); // not thread safe
_current_info = this;
memset((void*)this, 0, sizeof(FileMapInfo));
_file_offset = 0;
_file_open = false;
_header = new FileMapHeader();
_header->_version = _invalid_version;
_header->_has_platform_or_app_classes = true;
}
FileMapInfo::~FileMapInfo() {
assert(_current_info == this, "must be singleton"); // not thread safe
_current_info = NULL;
}
void FileMapInfo::populate_header(size_t alignment) {
_header->populate(this, alignment);
}
void FileMapInfo::FileMapHeader::populate(FileMapInfo* mapinfo, size_t alignment) {
_magic = 0xf00baba2;
_version = _current_version;
_alignment = alignment;
_obj_alignment = ObjectAlignmentInBytes;
_compact_strings = CompactStrings;
_narrow_oop_mode = Universe::narrow_oop_mode();
_narrow_oop_base = Universe::narrow_oop_base();
_narrow_oop_shift = Universe::narrow_oop_shift();
_max_heap_size = MaxHeapSize;
_narrow_klass_base = Universe::narrow_klass_base();
_narrow_klass_shift = Universe::narrow_klass_shift();
_shared_path_table_size = mapinfo->_shared_path_table_size;
_shared_path_table = mapinfo->_shared_path_table;
_shared_path_entry_size = mapinfo->_shared_path_entry_size;
// 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();
_verify_local = BytecodeVerificationLocal;
_verify_remote = BytecodeVerificationRemote;
_has_platform_or_app_classes = ClassLoaderExt::has_platform_or_app_classes();
}
void SharedClassPathEntry::init(const char* name, bool is_modules_image, TRAPS) {
assert(DumpSharedSpaces, "dump time only");
_timestamp = 0;
_filesize = 0;
struct stat st;
if (os::stat(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;
}
_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.", name);
}
size_t len = strlen(name) + 1;
_name = MetadataFactory::new_array<char>(ClassLoaderData::the_null_class_loader_data(), (int)len, THREAD);
strcpy(_name->data(), 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);
}
}
return ok;
}
void SharedClassPathEntry::metaspace_pointers_do(MetaspaceClosure* it) {
it->push(&_name);
it->push(&_manifest);
}
void FileMapInfo::allocate_shared_path_table() {
assert(DumpSharedSpaces, "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");
size_t entry_size = sizeof(SharedClassPathEntry); // assert ( should be 8 byte aligned??)
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;
_shared_path_table = MetadataFactory::new_array<u8>(loader_data, (int)(bytes + 7 / 8), THREAD);
_shared_path_table_size = num_entries;
_shared_path_entry_size = entry_size;
// 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(cpe->name(), is_jrt, 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 == 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(acpe->name(), false, 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(mpe->name(), false, THREAD);
EXCEPTION_MARK;
update_shared_classpath(mpe, ent, THREAD);
mpe = mpe->next();
i++;
}
assert(i == num_entries, "number of shared path entry mismatch");
}
void FileMapInfo::check_nonempty_dir_in_shared_path_table() {
assert(DumpSharedSpaces, "dump time only");
bool has_nonempty_dir = false;
int end = _shared_path_table_size;
if (!ClassLoaderExt::has_platform_or_app_classes()) {
// only check the boot path if no app class is loaded
end = ClassLoaderExt::app_class_paths_start_index();
}
for (int i = 0; i < end; 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);
}
}
}
}
bool FileMapInfo::validate_shared_path_table() {
assert(UseSharedSpaces, "runtime only");
_validating_shared_path_table = true;
_shared_path_table = _header->_shared_path_table;
_shared_path_entry_size = _header->_shared_path_entry_size;
_shared_path_table_size = _header->_shared_path_table_size;
int module_paths_start_index = _header->_app_module_paths_start_index;
// If the shared archive contain app or platform classes, validate all entries
// in the shared path table. Otherwise, only validate the boot path entries (with
// entry index < _app_class_paths_start_index).
int count = _header->has_platform_or_app_classes() ?
_shared_path_table_size : _header->_app_class_paths_start_index;
for (int i=0; i<count; i++) {
if (i < module_paths_start_index) {
if (shared_path(i)->validate()) {
log_info(class, path)("ok");
}
} 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 (!PrintSharedArchiveAndExit) {
_validating_shared_path_table = false;
_shared_path_table = NULL;
_shared_path_table_size = 0;
return false;
}
}
_validating_shared_path_table = false;
return true;
}
// Read the FileMapInfo information from the file.
bool FileMapInfo::init_from_file(int fd) {
size_t sz = _header->data_size();
char* addr = _header->data();
size_t n = os::read(fd, addr, (unsigned int)sz);
if (n != sz) {
fail_continue("Unable to read the file header.");
return false;
}
if (_header->_version != current_version()) {
fail_continue("The shared archive file has the wrong version.");
return false;
}
_file_offset = (long)n;
size_t info_size = _header->_paths_misc_info_size;
_paths_misc_info = NEW_C_HEAP_ARRAY_RETURN_NULL(char, info_size, mtClass);
if (_paths_misc_info == NULL) {
fail_continue("Unable to read the file header.");
return false;
}
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;
}
size_t len = lseek(fd, 0, SEEK_END);
struct FileMapInfo::FileMapHeader::space_info* si =
&_header->_space[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;
}
_file_offset += (long)n;
return true;
}
// Read the FileMapInfo information from the file.
bool FileMapInfo::open_for_read() {
_full_path = Arguments::GetSharedArchivePath();
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.");
} 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() {
_full_path = Arguments::GetSharedArchivePath();
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;
align_file_position();
size_t sz = _header->data_size();
char* addr = _header->data();
write_bytes(addr, (int)sz); // skip the C++ vtable
write_bytes(ClassLoader::get_shared_paths_misc_info(), info_size);
align_file_position();
}
// Dump region to file.
void FileMapInfo::write_region(int region, char* base, size_t size,
bool read_only, bool allow_exec) {
struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[region];
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(base), _file_offset);
} else {
si->_file_offset = _file_offset;
}
if (MetaspaceShared::is_heap_region(region)) {
assert((base - (char*)Universe::narrow_oop_base()) % HeapWordSize == 0, "Sanity");
if (base != NULL) {
si->_addr._offset = (intx)CompressedOops::encode_not_null((oop)base);
} else {
si->_addr._offset = 0;
}
} else {
si->_addr._base = base;
}
si->_used = size;
si->_read_only = read_only;
si->_allow_exec = allow_exec;
si->_crc = ClassLoader::crc32(0, base, (jint)size);
if (base != NULL) {
write_bytes_aligned(base, (int)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,
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");
}
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);
}
return total_size;
}
// Dump bytes to file -- at the current file position.
void FileMapInfo::write_bytes(const void* buffer, int nbytes) {
if (_file_open) {
int n = ::write(_fd, buffer, nbytes);
if (n != nbytes) {
// It is dangerous to leave the corrupted shared archive file around,
// close and remove the file. See bug 6372906.
close();
remove(_full_path);
fail_stop("Unable to write to shared archive file.");
}
}
_file_offset += nbytes;
}
// 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, int 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;
struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[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 = _header->region_addr(idx);
char *base = os::remap_memory(_fd, _full_path, si->_file_offset,
addr, size, false /* !read_only */,
si->_allow_exec);
close();
if (base == NULL) {
fail_continue("Unable to remap shared readonly space (errno=%d).", errno);
return false;
}
if (base != addr) {
fail_continue("Unable to remap shared readonly space at required address.");
return false;
}
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 = _header->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", "OptionalData",
"String1", "String2", "OpenArchive1", "OpenArchive2" };
char* FileMapInfo::map_region(int i, char** top_ret) {
assert(!MetaspaceShared::is_heap_region(i), "sanity");
struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
size_t used = si->_used;
size_t alignment = os::vm_allocation_granularity();
size_t size = align_up(used, alignment);
char *requested_addr = _header->region_addr(i);
// If a tool agent is in use (debugging enabled), we must map the address space RW
if (JvmtiExport::can_modify_any_class() || JvmtiExport::can_walk_any_space()) {
si->_read_only = false;
}
// 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]);
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 (!verify_region_checksum(i)) {
return NULL;
}
*top_ret = base + size;
return base;
}
static MemRegion *string_ranges = NULL;
static MemRegion *open_archive_heap_ranges = NULL;
static int num_string_ranges = 0;
static int num_open_archive_heap_ranges = 0;
#if INCLUDE_CDS_JAVA_HEAP
//
// Map the shared string objects and open archive heap objects to the runtime
// java heap.
//
// The shared strings are mapped near the runtime java heap top. The
// mapped strings contain no out-going references to any other java heap
// regions. GC does not write into the mapped shared strings.
//
// The open archive heap objects are mapped below the shared strings in
// the runtime java heap. The mapped open archive heap data only contain
// references to the shared strings 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() {
if (MetaspaceShared::is_heap_object_archiving_allowed()) {
log_info(cds)("Archived 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)("Archived narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
p2i(narrow_klass_base()), narrow_klass_shift());
// Check that all the narrow oop and klass encodings match the archive
if (narrow_oop_mode() != Universe::narrow_oop_mode() ||
narrow_oop_base() != Universe::narrow_oop_base() ||
narrow_oop_shift() != Universe::narrow_oop_shift() ||
narrow_klass_base() != Universe::narrow_klass_base() ||
narrow_klass_shift() != Universe::narrow_klass_shift()) {
if (log_is_enabled(Info, cds) && _header->_space[MetaspaceShared::first_string]._used > 0) {
log_info(cds)("Cached heap data from the CDS archive is being ignored. "
"The current CompressedOops/CompressedClassPointers encoding differs from "
"that archived due to heap size change. The archive was dumped using max heap "
"size " UINTX_FORMAT "M.", max_heap_size()/M);
log_info(cds)("Current narrow_oop_mode = %d, narrow_oop_base = " PTR_FORMAT ", narrow_oop_shift = %d",
Universe::narrow_oop_mode(), p2i(Universe::narrow_oop_base()),
Universe::narrow_oop_shift());
log_info(cds)("Current narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",
p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift());
}
} else {
// First, map string regions as closed archive heap regions.
// GC does not write into the regions.
if (map_heap_data(&string_ranges,
MetaspaceShared::first_string,
MetaspaceShared::max_strings,
&num_string_ranges)) {
StringTable::set_shared_string_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 */)) {
MetaspaceShared::set_open_archive_heap_region_mapped();
}
}
}
} else {
if (log_is_enabled(Info, cds) && _header->_space[MetaspaceShared::first_string]._used > 0) {
log_info(cds)("Cached heap data from the CDS archive is being ignored. UseG1GC, "
"UseCompressedOops and UseCompressedClassPointers are required.");
}
}
if (!StringTable::shared_string_mapped()) {
assert(string_ranges == NULL && num_string_ranges == 0, "sanity");
}
if (!MetaspaceShared::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];
struct FileMapInfo::FileMapHeader::space_info* si;
int region_num = 0;
for (int i = first;
i < first + max; i++) {
si = &_header->_space[i];
size_t used = si->_used;
if (used > 0) {
size_t size = used;
char* requested_addr = (char*)((void*)CompressedOops::decode_not_null(
(narrowOop)si->_addr._offset));
regions[region_num] = MemRegion((HeapWord*)requested_addr, size / HeapWordSize);
region_num ++;
}
}
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 = &_header->_space[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.");
return false;
}
}
if (!verify_mapped_heap_regions(first, region_num)) {
// 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;
}
bool FileMapInfo::verify_mapped_heap_regions(int first, int num) {
assert(num > 0, "sanity");
for (int i = first; i < first + num; i++) {
if (!verify_region_checksum(i)) {
return false;
}
}
return true;
}
void FileMapInfo::fixup_mapped_heap_regions() {
// If any string regions were found, call the fill routine to make them parseable.
// Note that string_ranges may be non-NULL even if no ranges were found.
if (num_string_ranges != 0) {
assert(string_ranges != NULL, "Null string_ranges array with non-zero count");
G1CollectedHeap::heap()->fill_archive_regions(string_ranges, num_string_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::verify_region_checksum(int i) {
assert(i >= 0 && i < MetaspaceShared::n_regions, "invalid region");
if (!VerifySharedSpaces) {
return true;
}
size_t sz = _header->_space[i]._used;
if (sz == 0) {
return true; // no data
}
if ((MetaspaceShared::is_string_region(i) &&
!StringTable::shared_string_mapped()) ||
(MetaspaceShared::is_open_archive_heap_region(i) &&
!MetaspaceShared::open_archive_heap_region_mapped())) {
return true; // archived heap data is not mapped
}
const char* buf = _header->region_addr(i);
int crc = ClassLoader::crc32(0, buf, (jint)sz);
if (crc != _header->_space[i]._crc) {
fail_continue("Checksum verification failed.");
return false;
}
return true;
}
// Unmap a memory region in the address space.
void FileMapInfo::unmap_region(int i) {
assert(!MetaspaceShared::is_heap_region(i), "sanity");
struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
size_t used = si->_used;
size_t size = align_up(used, os::vm_allocation_granularity());
if (used == 0) {
return;
}
char* addr = _header->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) {
it->push(&_shared_path_table);
for (int i=0; i<_shared_path_table_size; i++) {
shared_path(i)->metaspace_pointers_do(it);
}
}
FileMapInfo* FileMapInfo::_current_info = NULL;
Array<u8>* FileMapInfo::_shared_path_table = NULL;
int FileMapInfo::_shared_path_table_size = 0;
size_t FileMapInfo::_shared_path_entry_size = 0x1234baad;
bool FileMapInfo::_validating_shared_path_table = 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() {
assert(UseSharedSpaces, "UseSharedSpaces expected.");
if (!open_for_read()) {
return false;
}
init_from_file(_fd);
if (!validate_header()) {
return false;
}
return true;
}
char* FileMapInfo::FileMapHeader::region_addr(int idx) {
if (MetaspaceShared::is_heap_region(idx)) {
return _space[idx]._used > 0 ?
(char*)((void*)CompressedOops::decode_not_null((narrowOop)_space[idx]._addr._offset)) : NULL;
} else {
return _space[idx]._addr._base;
}
}
int FileMapInfo::FileMapHeader::compute_crc() {
char* header = data();
// start computing from the field after _crc
char* buf = (char*)&_crc + sizeof(int);
size_t sz = data_size() - (buf - header);
int crc = ClassLoader::crc32(0, buf, (jint)sz);
return crc;
}
// This function should only be called during run time with UseSharedSpaces enabled.
bool FileMapInfo::FileMapHeader::validate() {
if (VerifySharedSpaces && compute_crc() != _crc) {
fail_continue("Header checksum verification failed.");
return false;
}
if (!Arguments::has_jimage()) {
FileMapInfo::fail_continue("The shared archive file cannot be used with an exploded module build.");
return false;
}
if (_version != current_version()) {
FileMapInfo::fail_continue("The shared archive file is the wrong version.");
return false;
}
if (_magic != (int)0xf00baba2) {
FileMapInfo::fail_continue("The shared archive file has a bad magic number.");
return false;
}
char header_version[JVM_IDENT_MAX];
get_header_version(header_version);
if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) {
log_info(class, path)("expected: %s", header_version);
log_info(class, path)("actual: %s", _jvm_ident);
FileMapInfo::fail_continue("The shared archive file was created by a different"
" version or build of HotSpot");
return false;
}
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 be 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;
}
return true;
}
bool FileMapInfo::validate_header() {
bool status = _header->validate();
if (status) {
if (!ClassLoader::check_shared_paths_misc_info(_paths_misc_info, _header->_paths_misc_info_size)) {
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 = _header->region_addr(idx);
if (p >= base && p < base + _header->_space[idx]._used) {
return true;
}
return false;
}
void FileMapInfo::print_shared_spaces() {
tty->print_cr("Shared Spaces:");
for (int i = 0; i < MetaspaceShared::n_regions; i++) {
struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
char *base = _header->region_addr(i);
tty->print(" %s " INTPTR_FORMAT "-" INTPTR_FORMAT,
shared_region_name[i],
p2i(base), p2i(base + si->_used));
}
}
// Unmap mapped regions of shared space.
void FileMapInfo::stop_sharing_and_unmap(const char* msg) {
MetaspaceObj::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++) {
char *addr = map_info->_header->region_addr(i);
if (addr != NULL && !MetaspaceShared::is_heap_region(i)) {
map_info->unmap_region(i);
map_info->_header->_space[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(string_ranges,
num_string_ranges,
false);
} else if (DumpSharedSpaces) {
fail_stop("%s", msg);
}
}