/* * 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/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 "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/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 # include #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 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; if (MetaspaceShared::is_heap_object_archiving_allowed()) { _g1_reserved = G1CollectedHeap::heap()->g1_reserved(); } // 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(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(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* buf = MetadataFactory::new_array(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; ivalidate()) { 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); 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 = 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 = 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) { 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 *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 *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; 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"); 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 bool FileMapInfo::has_heap_regions() { return (_header->_space[MetaspaceShared::first_string]._used > 0); } // // 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_impl() { if (!MetaspaceShared::is_heap_object_archiving_allowed()) { log_info(cds)("Cached heap data from the CDS archive is being ignored. UseG1GC, " "UseCompressedOops and UseCompressedClassPointers are required."); return; } if (narrow_klass_base() != Universe::narrow_klass_base() || narrow_klass_shift() != Universe::narrow_klass_shift()) { log_info(cds)("Cached heap data from the CDS archive need to be relocated because"); log_info(cds)("the CDS archive was created with an incompatible heap size: " UINTX_FORMAT "M.", max_heap_size()/M); log_info(cds)("Current narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d", p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift()); return; } 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()); ptrdiff_t delta = 0; if (narrow_oop_mode() != Universe::narrow_oop_mode() || narrow_oop_base() != Universe::narrow_oop_base() || narrow_oop_shift() != Universe::narrow_oop_shift()) { log_info(cds)("Cached heap data from the CDS archive need to be relocated because"); log_info(cds)("the CDS archive was created with an incompatible 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()); _heap_pointers_need_relocation = true; // dumptime heap end ------------v // [ |archived heap regions| ] runtime heap end ------v // [ |archived heap regions| ] // |<-----delta-------------------->| // // At dump time, the archived heap region were near the top of the heap. // At run time, that region may not be inside the heap, so we move it so // that it's now near the top of teh runtime time. This can be done by // the simple math of adding the delta as shown above. address dumptime_heap_end = (address)_header->_g1_reserved.end(); address runtime_heap_end = (address)G1CollectedHeap::heap()->g1_reserved().end(); delta = runtime_heap_end - dumptime_heap_end; } HeapShared::init_narrow_oop_decoding(narrow_oop_base() + delta, narrow_oop_shift()); // 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(); } } } void FileMapInfo::map_heap_regions() { if (has_heap_regions()) { map_heap_regions_impl(); } 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]; FileMapHeader::space_info* si; int region_num = 0; for (int i = first; i < first + max; i++) { si = &_header->_space[i]; size_t size = si->_used; if (size > 0) { char* requested_addr = (char*)((void*)HeapShared::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); 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); 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) { for (int i = first; i <= first + num; i++) { if (!verify_region_checksum(i)) { return false; } } return true; } void FileMapInfo::relocate_archived_heap_embedded_pointers() { if (!_heap_pointers_need_relocation) { return; } relocate_archived_heap_embedded_pointers_impl(string_ranges, num_string_ranges); relocate_archived_heap_embedded_pointers_impl(open_archive_heap_ranges, num_open_archive_heap_ranges); } class RelocateInternalPointers: public BasicOopIterateClosure { public: virtual bool should_verify_oops(void) { return false; } virtual void do_oop(narrowOop *p) { narrowOop v = *p; if (!CompressedOops::is_null(v)) { oop o = HeapShared::decode_not_null(v); RawAccess::oop_store(p, o); } } virtual void do_oop(oop *p) { ShouldNotReachHere(); } }; void FileMapInfo::relocate_archived_heap_embedded_pointers_impl(MemRegion *heap_mem, int num) { RelocateInternalPointers relocator; for (int i=0; ioop_iterate(&relocator); p += o->size(); } } } // 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 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) { if (num > 0) { assert(regions != NULL, "Null archive ranges array with non-zero count"); G1CollectedHeap::heap()->dealloc_archive_regions(regions, num); } } #endif // INCLUDE_CDS_JAVA_HEAP 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_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"); 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; bool FileMapInfo::_heap_pointers_need_relocation = false; Array* 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) { 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); map_info->dealloc_archive_heap_regions(string_ranges, num_string_ranges); } else if (DumpSharedSpaces) { fail_stop("%s", msg); } }