/*
* Copyright (c) 2003, 2016, 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 "classfile/classLoader.hpp"
#include "classfile/compactHashtable.inline.hpp"
#include "classfile/sharedClassUtil.hpp"
#include "classfile/symbolTable.hpp"
#include "classfile/systemDictionaryShared.hpp"
#include "classfile/altHashing.hpp"
#if INCLUDE_ALL_GCS
#include "gc/g1/g1CollectedHeap.hpp"
#endif
#include "memory/filemap.hpp"
#include "memory/metadataFactory.hpp"
#include "memory/oopFactory.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/defaultStream.hpp"
# 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_classpath_entry_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 (PrintSharedSpaces) {
tty->print_cr("UseSharedSpaces: %s", msg);
}
}
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(this, 0, sizeof(FileMapInfo));
_file_offset = 0;
_file_open = false;
_header = SharedClassUtil::allocate_file_map_header();
_header->_version = _invalid_version;
}
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);
}
size_t FileMapInfo::FileMapHeader::data_size() {
return SharedClassUtil::file_map_header_size() - sizeof(FileMapInfo::FileMapHeaderBase);
}
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_shift = Universe::narrow_oop_shift();
_max_heap_size = MaxHeapSize;
_narrow_klass_base = Universe::narrow_klass_base();
_narrow_klass_shift = Universe::narrow_klass_shift();
_classpath_entry_table_size = mapinfo->_classpath_entry_table_size;
_classpath_entry_table = mapinfo->_classpath_entry_table;
_classpath_entry_size = mapinfo->_classpath_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);
}
void FileMapInfo::allocate_classpath_entry_table() {
int bytes = 0;
int count = 0;
char* strptr = NULL;
char* strptr_max = NULL;
Thread* THREAD = Thread::current();
ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
size_t entry_size = SharedClassUtil::shared_class_path_entry_size();
for (int pass=0; pass<2; pass++) {
ClassPathEntry *cpe = ClassLoader::classpath_entry(0);
for (int cur_entry = 0 ; cpe != NULL; cpe = cpe->next(), cur_entry++) {
const char *name = cpe->name();
int name_bytes = (int)(strlen(name) + 1);
if (pass == 0) {
count ++;
bytes += (int)entry_size;
bytes += name_bytes;
log_info(classpath)("add main shared path (%s) %s", (cpe->is_jar_file() ? "jar" : "dir"), name);
} else {
SharedClassPathEntry* ent = shared_classpath(cur_entry);
if (cpe->is_jar_file()) {
struct stat st;
if (os::stat(name, &st) != 0) {
// 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 jar file %s.", name);
}
EXCEPTION_MARK; // The following call should never throw, but would exit VM on error.
SharedClassUtil::update_shared_classpath(cpe, ent, st.st_mtime, st.st_size, THREAD);
} else {
struct stat st;
if (os::stat(name, &st) == 0) {
if (cpe->is_jrt()) {
// it's the "modules" jimage
ent->_timestamp = st.st_mtime;
ent->_filesize = st.st_size;
} else if ((st.st_mode & S_IFDIR) == S_IFDIR) {
if (!os::dir_is_empty(name)) {
ClassLoader::exit_with_path_failure(
"Cannot have non-empty directory in archived classpaths", name);
}
ent->_filesize = -1;
}
}
if (ent->_filesize == 0) {
// unknown
ent->_filesize = -2;
}
}
ent->_name = strptr;
if (strptr + name_bytes <= strptr_max) {
strncpy(strptr, name, (size_t)name_bytes); // name_bytes includes trailing 0.
strptr += name_bytes;
} else {
assert(0, "miscalculated buffer size");
}
}
}
if (pass == 0) {
EXCEPTION_MARK; // The following call should never throw, but would exit VM on error.
Array<u8>* arr = MetadataFactory::new_array<u8>(loader_data, (bytes + 7)/8, THREAD);
strptr = (char*)(arr->data());
strptr_max = strptr + bytes;
SharedClassPathEntry* table = (SharedClassPathEntry*)strptr;
strptr += entry_size * count;
_classpath_entry_table_size = count;
_classpath_entry_table = table;
_classpath_entry_size = entry_size;
}
}
}
bool FileMapInfo::validate_classpath_entry_table() {
_validating_classpath_entry_table = true;
int count = _header->_classpath_entry_table_size;
_classpath_entry_table = _header->_classpath_entry_table;
_classpath_entry_size = _header->_classpath_entry_size;
for (int i=0; i<count; i++) {
SharedClassPathEntry* ent = shared_classpath(i);
struct stat st;
const char* name = ent->_name;
bool ok = true;
log_info(classpath)("checking shared classpath entry: %s", name);
if (os::stat(name, &st) != 0) {
fail_continue("Required classpath entry does not exist: %s", name);
ok = false;
} else if (ent->is_dir()) {
if (!os::dir_is_empty(name)) {
fail_continue("directory is not empty: %s", name);
ok = false;
}
} else if (ent->is_jar_or_bootimage()) {
if (ent->_timestamp != st.st_mtime ||
ent->_filesize != st.st_size) {
ok = false;
if (PrintSharedArchiveAndExit) {
fail_continue(ent->_timestamp != st.st_mtime ?
"Timestamp mismatch" :
"File size mismatch");
} else {
fail_continue("A jar/jimage file is not the one used while building"
" the shared archive file: %s", name);
}
}
}
if (ok) {
log_info(classpath)("ok");
} else if (!PrintSharedArchiveAndExit) {
_validating_classpath_entry_table = false;
return false;
}
}
_classpath_entry_table_size = _header->_classpath_entry_table_size;
_validating_classpath_entry_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::mc];
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 = 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();
if (PrintSharedSpaces) {
tty->print_cr("Dumping shared data to file: ");
tty->print_cr(" %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 = 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 shared spaces to file.
void FileMapInfo::write_space(int i, Metaspace* space, bool read_only) {
align_file_position();
size_t used = space->used_bytes_slow(Metaspace::NonClassType);
size_t capacity = space->capacity_bytes_slow(Metaspace::NonClassType);
struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
write_region(i, (char*)space->bottom(), used, capacity, read_only, false);
}
// Dump region to file.
void FileMapInfo::write_region(int region, char* base, size_t size,
size_t capacity, 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.");
if (PrintSharedSpaces) {
tty->print_cr("Shared file region %d: " SIZE_FORMAT_HEX_W(6) " bytes, addr " INTPTR_FORMAT
" file offset " SIZE_FORMAT_HEX_W(6), region, size, p2i(base), _file_offset);
}
} else {
si->_file_offset = _file_offset;
}
if (MetaspaceShared::is_string_region(region)) {
assert((base - (char*)Universe::narrow_oop_base()) % HeapWordSize == 0, "Sanity");
if (base != NULL) {
si->_addr._offset = (intx)oopDesc::encode_heap_oop_not_null((oop)base);
} else {
si->_addr._offset = 0;
}
} else {
si->_addr._base = base;
}
si->_used = size;
si->_capacity = capacity;
si->_read_only = read_only;
si->_allow_exec = allow_exec;
si->_crc = ClassLoader::crc32(0, base, (jint)size);
write_bytes_aligned(base, (int)size);
}
// Write the string space. The string space contains one or multiple GC(G1) regions.
// When the total string space size is smaller than one GC region of the dump time,
// only one string region is used for shared strings.
//
// If the total string space size is bigger than one GC region, there would be more
// than one GC regions allocated for shared strings. The first/bottom GC region might
// be a partial GC region with the empty portion at the higher address within that region.
// The non-empty portion of the first region is written into the archive as one string
// region. The rest are consecutive full GC regions if they exist, which can be written
// out in one chunk as another string region.
void FileMapInfo::write_string_regions(GrowableArray<MemRegion> *regions) {
for (int i = MetaspaceShared::first_string;
i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
char* start = NULL;
size_t size = 0;
if (regions->is_nonempty()) {
if (i == MetaspaceShared::first_string) {
MemRegion first = regions->first();
start = (char*)first.start();
size = first.byte_size();
} else {
int len = regions->length();
if (len > 1) {
start = (char*)regions->at(1).start();
size = (char*)regions->at(len - 1).end() - start;
}
}
}
write_region(i, start, size, size, false, false);
}
}
// 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_size_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 = 0;
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_size_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() {
struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[0];
char* requested_addr = _header->region_addr(0);
size_t size = FileMapInfo::shared_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[] = { "ReadOnly", "ReadWrite", "MiscData", "MiscCode",
"String1", "String2" };
char* FileMapInfo::map_region(int i) {
assert(!MetaspaceShared::is_string_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_size_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
return base;
}
static MemRegion *string_ranges = NULL;
static int num_ranges = 0;
bool FileMapInfo::map_string_regions() {
#if INCLUDE_ALL_GCS
if (UseG1GC && UseCompressedOops && UseCompressedClassPointers) {
// Check that all the narrow oop and klass encodings match the archive
if (narrow_oop_mode() != Universe::narrow_oop_mode() ||
narrow_oop_shift() != Universe::narrow_oop_shift() ||
narrow_klass_base() != Universe::narrow_klass_base() ||
narrow_klass_shift() != Universe::narrow_klass_shift()) {
if (PrintSharedSpaces && _header->_space[MetaspaceShared::first_string]._used > 0) {
tty->print_cr("Shared string 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);
}
} else {
string_ranges = new MemRegion[MetaspaceShared::max_strings];
struct FileMapInfo::FileMapHeader::space_info* si;
for (int i = MetaspaceShared::first_string;
i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
si = &_header->_space[i];
size_t used = si->_used;
if (used > 0) {
size_t size = used;
char* requested_addr = (char*)((void*)oopDesc::decode_heap_oop_not_null(
(narrowOop)si->_addr._offset));
string_ranges[num_ranges] = MemRegion((HeapWord*)requested_addr, size / HeapWordSize);
num_ranges ++;
}
}
if (num_ranges == 0) {
StringTable::ignore_shared_strings(true);
return true; // no shared string data
}
// Check that ranges are within the java heap
if (!G1CollectedHeap::heap()->check_archive_addresses(string_ranges, num_ranges)) {
fail_continue("Unable to allocate shared string space: range is not "
"within java heap.");
return false;
}
// allocate from java heap
if (!G1CollectedHeap::heap()->alloc_archive_regions(string_ranges, num_ranges)) {
fail_continue("Unable to allocate shared string space: range is "
"already in use.");
return false;
}
// Map the string data. No need to call MemTracker::record_virtual_memory_type()
// for mapped string regions as they are part of the reserved java heap, which
// is already recorded.
for (int i = 0; i < num_ranges; i++) {
si = &_header->_space[MetaspaceShared::first_string + i];
char* addr = (char*)string_ranges[i].start();
char* base = os::map_memory(_fd, _full_path, si->_file_offset,
addr, string_ranges[i].byte_size(), si->_read_only,
si->_allow_exec);
if (base == NULL || base != addr) {
// dealloc the string regions from java heap
dealloc_string_regions();
fail_continue("Unable to map shared string space at required address.");
return false;
}
}
if (!verify_string_regions()) {
// dealloc the string regions from java heap
dealloc_string_regions();
fail_continue("Shared string regions are corrupt");
return false;
}
// the shared string data is mapped successfully
return true;
}
} else {
if (PrintSharedSpaces && _header->_space[MetaspaceShared::first_string]._used > 0) {
tty->print_cr("Shared string data from the CDS archive is being ignored. UseG1GC, "
"UseCompressedOops and UseCompressedClassPointers are required.");
}
}
// if we get here, the shared string data is not mapped
assert(string_ranges == NULL && num_ranges == 0, "sanity");
StringTable::ignore_shared_strings(true);
#endif
return true;
}
bool FileMapInfo::verify_string_regions() {
for (int i = MetaspaceShared::first_string;
i < MetaspaceShared::first_string + MetaspaceShared::max_strings; i++) {
if (!verify_region_checksum(i)) {
return false;
}
}
return true;
}
void FileMapInfo::fixup_string_regions() {
#if INCLUDE_ALL_GCS
// 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_ranges != 0) {
assert(string_ranges != NULL, "Null string_ranges array with non-zero count");
G1CollectedHeap::heap()->fill_archive_regions(string_ranges, num_ranges);
}
#endif
}
bool FileMapInfo::verify_region_checksum(int i) {
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_ignored()) {
return true; // shared string data are 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_string_region(i), "sanity");
struct FileMapInfo::FileMapHeader::space_info* si = &_header->_space[i];
size_t used = si->_used;
size_t size = align_size_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.");
}
}
// dealloc the archived string region from java heap
void FileMapInfo::dealloc_string_regions() {
#if INCLUDE_ALL_GCS
if (num_ranges > 0) {
assert(string_ranges != NULL, "Null string_ranges array with non-zero count");
G1CollectedHeap::heap()->dealloc_archive_regions(string_ranges, num_ranges);
}
#endif
}
void FileMapInfo::assert_mark(bool check) {
if (!check) {
fail_stop("Mark mismatch while restoring from shared file.");
}
}
FileMapInfo* FileMapInfo::_current_info = NULL;
SharedClassPathEntry* FileMapInfo::_classpath_entry_table = NULL;
int FileMapInfo::_classpath_entry_table_size = 0;
size_t FileMapInfo::_classpath_entry_size = 0x1234baad;
bool FileMapInfo::_validating_classpath_entry_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_classpath_entry_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;
}
SharedReadOnlySize = _header->_space[0]._capacity;
SharedReadWriteSize = _header->_space[1]._capacity;
SharedMiscDataSize = _header->_space[2]._capacity;
SharedMiscCodeSize = _header->_space[3]._capacity;
return true;
}
char* FileMapInfo::FileMapHeader::region_addr(int idx) {
if (MetaspaceShared::is_string_region(idx)) {
return (char*)((void*)oopDesc::decode_heap_oop_not_null(
(narrowOop)_space[idx]._addr._offset));
} 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;
}
bool FileMapInfo::FileMapHeader::validate() {
if (VerifySharedSpaces && compute_crc() != _crc) {
fail_continue("Header checksum verification failed.");
return false;
}
if (Arguments::patch_dirs() != NULL) {
FileMapInfo::fail_continue("The shared archive file cannot be used with -Xpatch.");
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(classpath)("expected: %s", header_version);
log_info(classpath)("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;
}
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:classpath=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;
}
// The following method is provided to see whether a given pointer
// falls in the mapped shared space.
// Param:
// p, The given pointer
// Return:
// True if the p is within the mapped shared space, otherwise, false.
bool FileMapInfo::is_in_shared_space(const void* p) {
for (int i = 0; i < MetaspaceShared::n_regions; i++) {
char *base;
if (MetaspaceShared::is_string_region(i) && _header->_space[i]._used == 0) {
continue;
}
base = _header->region_addr(i);
if (p >= base && p < base + _header->_space[i]._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) {
FileMapInfo *map_info = FileMapInfo::current_info();
if (map_info) {
map_info->fail_continue("%s", msg);
for (int i = 0; i < MetaspaceShared::num_non_strings; i++) {
char *addr = map_info->_header->region_addr(i);
if (addr != NULL && !MetaspaceShared::is_string_region(i)) {
map_info->unmap_region(i);
map_info->_header->_space[i]._addr._base = NULL;
}
}
// Dealloc the string regions only without unmapping. The string regions are part
// of the java heap. Unmapping of the heap regions are managed by GC.
map_info->dealloc_string_regions();
} else if (DumpSharedSpaces) {
fail_stop("%s", msg);
}
}