filemap.hpp revision 6872:16286b7d7c6e
169783Smsmith/* 269783Smsmith * Copyright (c) 2003, 2014, Oracle and/or its affiliates. All rights reserved. 369783Smsmith * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 469783Smsmith * 569783Smsmith * This code is free software; you can redistribute it and/or modify it 669783Smsmith * under the terms of the GNU General Public License version 2 only, as 769783Smsmith * published by the Free Software Foundation. 869783Smsmith * 969783Smsmith * This code is distributed in the hope that it will be useful, but WITHOUT 1069783Smsmith * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 1169783Smsmith * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 1269783Smsmith * version 2 for more details (a copy is included in the LICENSE file that 1369783Smsmith * accompanied this code). 1469783Smsmith * 1569783Smsmith * You should have received a copy of the GNU General Public License version 1669783Smsmith * 2 along with this work; if not, write to the Free Software Foundation, 1769783Smsmith * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 1869783Smsmith * 1969783Smsmith * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 2069783Smsmith * or visit www.oracle.com if you need additional information or have any 2169783Smsmith * questions. 2269783Smsmith * 2369783Smsmith */ 2469783Smsmith 2569783Smsmith#ifndef SHARE_VM_MEMORY_FILEMAP_HPP 2669783Smsmith#define SHARE_VM_MEMORY_FILEMAP_HPP 2769783Smsmith 2869783Smsmith#include "memory/metaspaceShared.hpp" 2969783Smsmith#include "memory/metaspace.hpp" 3069783Smsmith 3169783Smsmith// Layout of the file: 3269783Smsmith// header: dump of archive instance plus versioning info, datestamp, etc. 3369783Smsmith// [magic # = 0xF00BABA2] 3469783Smsmith// ... padding to align on page-boundary 3569783Smsmith// read-write space 3669783Smsmith// read-only space 3769783Smsmith// misc data (block offset table, string table, symbols, dictionary, etc.) 3869783Smsmith// tag(666) 3969783Smsmith 4069783Smsmithstatic const int JVM_IDENT_MAX = 256; 4169783Smsmith 4269783Smsmithclass Metaspace; 4369783Smsmith 4469783Smsmithclass SharedClassPathEntry VALUE_OBJ_CLASS_SPEC { 4569783Smsmithpublic: 4669783Smsmith const char *_name; 4769783Smsmith time_t _timestamp; // jar timestamp, 0 if is directory 4869783Smsmith long _filesize; // jar file size, -1 if is directory 4969783Smsmith bool is_dir() { 5069783Smsmith return _filesize == -1; 5169783Smsmith } 5269783Smsmith}; 5369783Smsmith 5469783Smsmithclass FileMapInfo : public CHeapObj<mtInternal> { 5569783Smsmithprivate: 5669783Smsmith friend class ManifestStream; 5769783Smsmith enum { 5869783Smsmith _invalid_version = -1, 5969783Smsmith _current_version = 2 6069783Smsmith }; 6169783Smsmith 6269783Smsmith bool _file_open; 6369783Smsmith int _fd; 6469783Smsmith long _file_offset; 6569783Smsmith 6669783Smsmithprivate: 6769783Smsmith static SharedClassPathEntry* _classpath_entry_table; 6869783Smsmith static int _classpath_entry_table_size; 6969783Smsmith static size_t _classpath_entry_size; 7069783Smsmith static bool _validating_classpath_entry_table; 7169783Smsmith 7269783Smsmith // FileMapHeader describes the shared space data in the file to be 7369783Smsmith // mapped. This structure gets written to a file. It is not a class, so 7469783Smsmith // that the compilers don't add any compiler-private data to it. 7569783Smsmith 7669783Smsmithpublic: 7769783Smsmith struct FileMapHeaderBase : public CHeapObj<mtClass> { 7869783Smsmith virtual bool validate() = 0; 7969783Smsmith virtual void populate(FileMapInfo* info, size_t alignment) = 0; 8069783Smsmith }; 8169783Smsmith struct FileMapHeader : FileMapHeaderBase { 8269783Smsmith // Use data() and data_size() to memcopy to/from the FileMapHeader. We need to 8369783Smsmith // avoid read/writing the C++ vtable pointer. 8469783Smsmith static size_t data_size(); 8569783Smsmith char* data() { 8669783Smsmith return ((char*)this) + sizeof(FileMapHeaderBase); 8769783Smsmith } 8869783Smsmith 8969783Smsmith int _magic; // identify file type. 9069783Smsmith int _version; // (from enum, above.) 9169783Smsmith size_t _alignment; // how shared archive should be aligned 9269783Smsmith int _obj_alignment; // value of ObjectAlignmentInBytes 9369783Smsmith 9469783Smsmith struct space_info { 9569783Smsmith int _file_offset; // sizeof(this) rounded to vm page size 9669783Smsmith char* _base; // copy-on-write base address 9769783Smsmith size_t _capacity; // for validity checking 9869783Smsmith size_t _used; // for setting space top on read 9969783Smsmith bool _read_only; // read only space? 10069783Smsmith bool _allow_exec; // executable code in space? 10169783Smsmith } _space[MetaspaceShared::n_regions]; 10269783Smsmith 10369783Smsmith // The following fields are all sanity checks for whether this archive 10469783Smsmith // will function correctly with this JVM and the bootclasspath it's 10569783Smsmith // invoked with. 10669783Smsmith char _jvm_ident[JVM_IDENT_MAX]; // identifier for jvm 10769783Smsmith 10869783Smsmith // The _paths_misc_info is a variable-size structure that records "miscellaneous" 10969783Smsmith // information during dumping. It is generated and validated by the 11069783Smsmith // SharedPathsMiscInfo class. See SharedPathsMiscInfo.hpp and sharedClassUtil.hpp for 11169783Smsmith // detailed description. 11269783Smsmith // 11369783Smsmith // The _paths_misc_info data is stored as a byte array in the archive file header, 11469783Smsmith // immediately after the _header field. This information is used only when 11569783Smsmith // checking the validity of the archive and is deallocated after the archive is loaded. 11669783Smsmith // 11769783Smsmith // Note that the _paths_misc_info does NOT include information for JAR files 11869783Smsmith // that existed during dump time. Their information is stored in _classpath_entry_table. 11969783Smsmith int _paths_misc_info_size; 12069783Smsmith 12169783Smsmith // The following is a table of all the class path entries that were used 12269783Smsmith // during dumping. At run time, we require these files to exist and have the same 12369783Smsmith // size/modification time, or else the archive will refuse to load. 12469783Smsmith // 12569783Smsmith // All of these entries must be JAR files. The dumping process would fail if a non-empty 12669783Smsmith // directory was specified in the classpaths. If an empty directory was specified 12769783Smsmith // it is checked by the _paths_misc_info as described above. 12869783Smsmith // 12969783Smsmith // FIXME -- if JAR files in the tail of the list were specified but not used during dumping, 13069783Smsmith // they should be removed from this table, to save space and to avoid spurious 13169783Smsmith // loading failures during runtime. 13269783Smsmith int _classpath_entry_table_size; 13369783Smsmith size_t _classpath_entry_size; 13469783Smsmith SharedClassPathEntry* _classpath_entry_table; 13569908Smsmith 13669908Smsmith virtual bool validate(); 13769783Smsmith virtual void populate(FileMapInfo* info, size_t alignment); 13869783Smsmith }; 13969783Smsmith 14069783Smsmith FileMapHeader * _header; 14169908Smsmith 14269908Smsmith const char* _full_path; 14369908Smsmith char* _paths_misc_info; 14469908Smsmith 14569908Smsmith static FileMapInfo* _current_info; 14669908Smsmith 14769908Smsmith bool init_from_file(int fd); 14869908Smsmith void align_file_position(); 14969783Smsmith bool validate_header_impl(); 15069908Smsmith 15169908Smsmithpublic: 15269908Smsmith FileMapInfo(); 15369908Smsmith ~FileMapInfo(); 15469908Smsmith 15569908Smsmith static int current_version() { return _current_version; } 15669908Smsmith void populate_header(size_t alignment); 15769908Smsmith bool validate_header(); 15869908Smsmith void invalidate(); 15969908Smsmith int version() { return _header->_version; } 16069908Smsmith size_t alignment() { return _header->_alignment; } 16169908Smsmith size_t space_capacity(int i) { return _header->_space[i]._capacity; } 16269908Smsmith char* region_base(int i) { return _header->_space[i]._base; } 16369908Smsmith struct FileMapHeader* header() { return _header; } 16469908Smsmith 16569908Smsmith static FileMapInfo* current_info() { 16669908Smsmith CDS_ONLY(return _current_info;) 16769908Smsmith NOT_CDS(return NULL;) 16869908Smsmith } 16969908Smsmith 17069908Smsmith static void assert_mark(bool check); 17169908Smsmith 17269908Smsmith // File manipulation. 17369908Smsmith bool initialize() NOT_CDS_RETURN_(false); 17469908Smsmith bool open_for_read(); 17569908Smsmith void open_for_write(); 17669908Smsmith void write_header(); 17769908Smsmith void write_space(int i, Metaspace* space, bool read_only); 17869908Smsmith void write_region(int region, char* base, size_t size, 17969908Smsmith size_t capacity, bool read_only, bool allow_exec); 18069908Smsmith void write_bytes(const void* buffer, int count); 18169908Smsmith void write_bytes_aligned(const void* buffer, int count); 18269908Smsmith char* map_region(int i); 18369908Smsmith void unmap_region(int i); 18469908Smsmith void close(); 18569908Smsmith bool is_open() { return _file_open; } 18669908Smsmith ReservedSpace reserve_shared_memory(); 18769908Smsmith 18869908Smsmith // JVM/TI RedefineClasses() support: 18969908Smsmith // Remap the shared readonly space to shared readwrite, private. 19069908Smsmith bool remap_shared_readonly_as_readwrite(); 19169908Smsmith 19269908Smsmith // Errors. 19369908Smsmith static void fail_stop(const char *msg, ...); 19469908Smsmith static void fail_continue(const char *msg, ...); 19569908Smsmith 19669908Smsmith // Return true if given address is in the mapped shared space. 19769783Smsmith bool is_in_shared_space(const void* p) NOT_CDS_RETURN_(false); 19869783Smsmith void print_shared_spaces() NOT_CDS_RETURN; 19969783Smsmith 20069783Smsmith static size_t shared_spaces_size() { 20169783Smsmith return align_size_up(SharedReadOnlySize + SharedReadWriteSize + 20269783Smsmith SharedMiscDataSize + SharedMiscCodeSize, 20369783Smsmith os::vm_allocation_granularity()); 20469783Smsmith } 20569783Smsmith 20669783Smsmith // Stop CDS sharing and unmap CDS regions. 20769783Smsmith static void stop_sharing_and_unmap(const char* msg); 20869783Smsmith 20969783Smsmith static void allocate_classpath_entry_table(); 21069783Smsmith bool validate_classpath_entry_table(); 21169783Smsmith 21269783Smsmith static SharedClassPathEntry* shared_classpath(int index) { 21369783Smsmith char* p = (char*)_classpath_entry_table; 21469783Smsmith p += _classpath_entry_size * index; 21569783Smsmith return (SharedClassPathEntry*)p; 21669783Smsmith } 21769783Smsmith static const char* shared_classpath_name(int index) { 21869783Smsmith return shared_classpath(index)->_name; 21969783Smsmith } 22069783Smsmith 22169783Smsmith static int get_number_of_share_classpaths() { 22269783Smsmith return _classpath_entry_table_size; 22369783Smsmith } 22469783Smsmith}; 22569783Smsmith 22669783Smsmith#endif // SHARE_VM_MEMORY_FILEMAP_HPP 22769783Smsmith