1 /* 2 * Copyright (c) 2003, 2018, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #ifndef SHARE_VM_MEMORY_FILEMAP_HPP 26 #define SHARE_VM_MEMORY_FILEMAP_HPP 27 28 #include "classfile/classLoader.hpp" 29 #include "memory/metaspaceShared.hpp" 30 #include "memory/metaspace.hpp" 31 #include "memory/universe.hpp" 32 #include "utilities/align.hpp" 33 34 // Layout of the file: 35 // header: dump of archive instance plus versioning info, datestamp, etc. 36 // [magic # = 0xF00BABA2] 37 // ... padding to align on page-boundary 38 // read-write space 39 // read-only space 40 // misc data (block offset table, string table, symbols, dictionary, etc.) 41 // tag(666) 42 43 static const int JVM_IDENT_MAX = 256; 44 45 class SharedClassPathEntry { 46 enum { 47 modules_image_entry, 48 jar_entry, 49 signed_jar_entry, 50 dir_entry, 51 unknown_entry 52 }; 53 protected: 54 u1 _type; 55 time_t _timestamp; // jar timestamp, 0 if is directory, modules image or other 56 long _filesize; // jar/jimage file size, -1 if is directory, -2 if other 57 Array<char>* _name; 58 Array<u1>* _manifest; 59 60 public: 61 void init(const char* name, bool is_modules_image, TRAPS); 62 void metaspace_pointers_do(MetaspaceClosure* it); 63 bool validate(bool is_class_path = true); 64 65 // The _timestamp only gets set for jar files. 66 bool has_timestamp() { 67 return _timestamp != 0; 68 } 69 bool is_dir() { return _type == dir_entry; } 70 bool is_modules_image() { return _type == modules_image_entry; } 71 bool is_jar() { return _type == jar_entry; } 72 bool is_signed() { return _type == signed_jar_entry; } 73 void set_is_signed() { 74 _type = signed_jar_entry; 75 } 76 time_t timestamp() const { return _timestamp; } 77 long filesize() const { return _filesize; } 78 const char* name() const { return _name->data(); } 79 const char* manifest() const { 80 return (_manifest == NULL) ? NULL : (const char*)_manifest->data(); 81 } 82 int manifest_size() const { 83 return (_manifest == NULL) ? 0 : _manifest->length(); 84 } 85 void set_manifest(Array<u1>* manifest) { 86 _manifest = manifest; 87 } 88 }; 89 90 class FileMapInfo : public CHeapObj<mtInternal> { 91 private: 92 friend class ManifestStream; 93 friend class VMStructs; 94 enum { 95 _invalid_version = -1, 96 _current_version = 3 97 }; 98 99 bool _file_open; 100 int _fd; 101 size_t _file_offset; 102 103 private: 104 static Array<u8>* _shared_path_table; 105 static int _shared_path_table_size; 106 static size_t _shared_path_entry_size; 107 static bool _validating_shared_path_table; 108 109 // FileMapHeader describes the shared space data in the file to be 110 // mapped. This structure gets written to a file. It is not a class, so 111 // that the compilers don't add any compiler-private data to it. 112 113 public: 114 struct FileMapHeaderBase : public CHeapObj<mtClass> { 115 // Need to put something here. Otherwise, in product build, because CHeapObj has no virtual 116 // methods, we would get sizeof(FileMapHeaderBase) == 1 with gcc. 117 intx _dummy; 118 }; 119 struct FileMapHeader : FileMapHeaderBase { 120 // Use data() and data_size() to memcopy to/from the FileMapHeader. We need to 121 // avoid read/writing the C++ vtable pointer. 122 static size_t data_size() { 123 return sizeof(FileMapHeader) - sizeof(FileMapInfo::FileMapHeaderBase); 124 } 125 char* data() { 126 return ((char*)this) + sizeof(FileMapHeaderBase); 127 } 128 129 int _magic; // identify file type. 130 int _crc; // header crc checksum. 131 int _version; // (from enum, above.) 132 size_t _alignment; // how shared archive should be aligned 133 int _obj_alignment; // value of ObjectAlignmentInBytes 134 address _narrow_oop_base; // compressed oop encoding base 135 int _narrow_oop_shift; // compressed oop encoding shift 136 bool _compact_strings; // value of CompactStrings 137 uintx _max_heap_size; // java max heap size during dumping 138 Universe::NARROW_OOP_MODE _narrow_oop_mode; // compressed oop encoding mode 139 int _narrow_klass_shift; // save narrow klass base and shift 140 address _narrow_klass_base; 141 char* _misc_data_patching_start; 142 char* _read_only_tables_start; 143 address _cds_i2i_entry_code_buffers; 144 size_t _cds_i2i_entry_code_buffers_size; 145 size_t _core_spaces_size; // number of bytes allocated by the core spaces 146 // (mc, md, ro, rw and od). 147 struct space_info { 148 int _crc; // crc checksum of the current space 149 size_t _file_offset; // sizeof(this) rounded to vm page size 150 union { 151 char* _base; // copy-on-write base address 152 intx _offset; // offset from the compressed oop encoding base, only used 153 // by archive heap space 154 } _addr; 155 size_t _used; // for setting space top on read 156 bool _read_only; // read only space? 157 bool _allow_exec; // executable code in space? 158 } _space[MetaspaceShared::n_regions]; 159 160 // The following fields are all sanity checks for whether this archive 161 // will function correctly with this JVM and the bootclasspath it's 162 // invoked with. 163 char _jvm_ident[JVM_IDENT_MAX]; // identifier for jvm 164 165 // The _paths_misc_info is a variable-size structure that records "miscellaneous" 166 // information during dumping. It is generated and validated by the 167 // SharedPathsMiscInfo class. See SharedPathsMiscInfo.hpp for 168 // detailed description. 169 // 170 // The _paths_misc_info data is stored as a byte array in the archive file header, 171 // immediately after the _header field. This information is used only when 172 // checking the validity of the archive and is deallocated after the archive is loaded. 173 // 174 // Note that the _paths_misc_info does NOT include information for JAR files 175 // that existed during dump time. Their information is stored in _shared_path_table. 176 int _paths_misc_info_size; 177 178 // The following is a table of all the class path entries that were used 179 // during dumping. At run time, we require these files to exist and have the same 180 // size/modification time, or else the archive will refuse to load. 181 // 182 // All of these entries must be JAR files. The dumping process would fail if a non-empty 183 // directory was specified in the classpaths. If an empty directory was specified 184 // it is checked by the _paths_misc_info as described above. 185 // 186 // FIXME -- if JAR files in the tail of the list were specified but not used during dumping, 187 // they should be removed from this table, to save space and to avoid spurious 188 // loading failures during runtime. 189 int _shared_path_table_size; 190 size_t _shared_path_entry_size; 191 Array<u8>* _shared_path_table; 192 193 jshort _app_class_paths_start_index; // Index of first app classpath entry 194 jshort _app_module_paths_start_index; // Index of first module path entry 195 bool _verify_local; // BytecodeVerificationLocal setting 196 bool _verify_remote; // BytecodeVerificationRemote setting 197 bool _has_platform_or_app_classes; // Archive contains app classes 198 199 void set_has_platform_or_app_classes(bool v) { 200 _has_platform_or_app_classes = v; 201 } 202 bool has_platform_or_app_classes() { return _has_platform_or_app_classes; } 203 204 char* region_addr(int idx); 205 206 bool validate(); 207 void populate(FileMapInfo* info, size_t alignment); 208 int compute_crc(); 209 }; 210 211 FileMapHeader * _header; 212 213 const char* _full_path; 214 char* _paths_misc_info; 215 216 static FileMapInfo* _current_info; 217 218 bool init_from_file(int fd); 219 void align_file_position(); 220 bool validate_header_impl(); 221 static void metaspace_pointers_do(MetaspaceClosure* it); 222 223 public: 224 FileMapInfo(); 225 ~FileMapInfo(); 226 227 static int current_version() { return _current_version; } 228 int compute_header_crc() { return _header->compute_crc(); } 229 void set_header_crc(int crc) { _header->_crc = crc; } 230 void populate_header(size_t alignment); 231 bool validate_header(); 232 void invalidate(); 233 int version() { return _header->_version; } 234 size_t alignment() { return _header->_alignment; } 235 Universe::NARROW_OOP_MODE narrow_oop_mode() { return _header->_narrow_oop_mode; } 236 address narrow_oop_base() const { return _header->_narrow_oop_base; } 237 int narrow_oop_shift() const { return _header->_narrow_oop_shift; } 238 uintx max_heap_size() const { return _header->_max_heap_size; } 239 address narrow_klass_base() const { return _header->_narrow_klass_base; } 240 int narrow_klass_shift() const { return _header->_narrow_klass_shift; } 241 struct FileMapHeader* header() { return _header; } 242 char* misc_data_patching_start() { return _header->_misc_data_patching_start; } 243 void set_misc_data_patching_start(char* p) { _header->_misc_data_patching_start = p; } 244 char* read_only_tables_start() { return _header->_read_only_tables_start; } 245 void set_read_only_tables_start(char* p) { _header->_read_only_tables_start = p; } 246 247 address cds_i2i_entry_code_buffers() { 248 return _header->_cds_i2i_entry_code_buffers; 249 } 250 void set_cds_i2i_entry_code_buffers(address addr) { 251 _header->_cds_i2i_entry_code_buffers = addr; 252 } 253 size_t cds_i2i_entry_code_buffers_size() { 254 return _header->_cds_i2i_entry_code_buffers_size; 255 } 256 void set_cds_i2i_entry_code_buffers_size(size_t s) { 257 _header->_cds_i2i_entry_code_buffers_size = s; 258 } 259 void set_core_spaces_size(size_t s) { _header->_core_spaces_size = s; } 260 size_t core_spaces_size() { return _header->_core_spaces_size; } 261 262 static FileMapInfo* current_info() { 263 CDS_ONLY(return _current_info;) 264 NOT_CDS(return NULL;) 265 } 266 267 static void assert_mark(bool check); 268 269 // File manipulation. 270 bool initialize() NOT_CDS_RETURN_(false); 271 bool open_for_read(); 272 void open_for_write(); 273 void write_header(); 274 void write_region(int region, char* base, size_t size, 275 bool read_only, bool allow_exec); 276 size_t write_archive_heap_regions(GrowableArray<MemRegion> *heap_mem, 277 int first_region_id, int max_num_regions); 278 void write_bytes(const void* buffer, int count); 279 void write_bytes_aligned(const void* buffer, int count); 280 char* map_region(int i, char** top_ret); 281 void map_heap_regions() NOT_CDS_JAVA_HEAP_RETURN; 282 void fixup_mapped_heap_regions() NOT_CDS_JAVA_HEAP_RETURN; 283 void unmap_region(int i); 284 bool verify_region_checksum(int i); 285 void close(); 286 bool is_open() { return _file_open; } 287 ReservedSpace reserve_shared_memory(); 288 289 // JVM/TI RedefineClasses() support: 290 // Remap the shared readonly space to shared readwrite, private. 291 bool remap_shared_readonly_as_readwrite(); 292 293 // Errors. 294 static void fail_stop(const char *msg, ...) ATTRIBUTE_PRINTF(1, 2); 295 static void fail_continue(const char *msg, ...) ATTRIBUTE_PRINTF(1, 2); 296 297 bool is_in_shared_region(const void* p, int idx) NOT_CDS_RETURN_(false); 298 void print_shared_spaces() NOT_CDS_RETURN; 299 300 // Stop CDS sharing and unmap CDS regions. 301 static void stop_sharing_and_unmap(const char* msg); 302 303 static void allocate_shared_path_table(); 304 static void check_nonempty_dir_in_shared_path_table(); 305 bool validate_shared_path_table(); 306 static void update_shared_classpath(ClassPathEntry *cpe, SharedClassPathEntry* ent, TRAPS); 307 308 static SharedClassPathEntry* shared_path(int index) { 309 if (index < 0) { 310 return NULL; 311 } 312 assert(index < _shared_path_table_size, "sanity"); 313 char* p = (char*)_shared_path_table->data(); 314 p += _shared_path_entry_size * index; 315 return (SharedClassPathEntry*)p; 316 } 317 318 static const char* shared_path_name(int index) { 319 assert(index >= 0, "Sanity"); 320 return shared_path(index)->name(); 321 } 322 323 static int get_number_of_shared_paths() { 324 return _shared_path_table_size; 325 } 326 327 private: 328 bool map_heap_data(MemRegion **heap_mem, int first, int max, int* num, 329 bool is_open = false) NOT_CDS_JAVA_HEAP_RETURN_(false); 330 bool verify_mapped_heap_regions(int first, int num) NOT_CDS_JAVA_HEAP_RETURN_(false); 331 void dealloc_archive_heap_regions(MemRegion* regions, int num) NOT_CDS_JAVA_HEAP_RETURN; 332 }; 333 334 #endif // SHARE_VM_MEMORY_FILEMAP_HPP