| /* |
| * Copyright (c) 2018, 2023, 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. |
| * |
| */ |
| |
| #ifndef SHARE_INCLUDE_CDS_H |
| #define SHARE_INCLUDE_CDS_H |
| |
| #include <stddef.h> |
| |
| // This file declares the CDS data structures that are used by the HotSpot Serviceability Agent |
| // (see C sources inside src/jdk.hotspot.agent). |
| // |
| // We should use only standard C types. Do not use custom types such as bool, intx, |
| // etc, to avoid introducing unnecessary dependencies to other HotSpot type declarations. |
| // |
| // Also, this is a C header file. Do not use C++ here. |
| |
| #define NUM_CDS_REGIONS 4 // this must be the same as MetaspaceShared::n_regions |
| #define CDS_ARCHIVE_MAGIC 0xf00baba2 |
| #define CDS_DYNAMIC_ARCHIVE_MAGIC 0xf00baba8 |
| #define CDS_GENERIC_HEADER_SUPPORTED_MIN_VERSION 13 |
| #define CURRENT_CDS_ARCHIVE_VERSION 18 |
| |
| typedef struct CDSFileMapRegion { |
| int _crc; // CRC checksum of this region. |
| int _read_only; // read only region? |
| int _allow_exec; // executable code in this region? |
| int _is_heap_region; // Used by SA and debug build. |
| int _is_bitmap_region; // Relocation bitmap for RO/RW regions (used by SA and debug build). |
| int _mapped_from_file; // Is this region mapped from a file? |
| // If false, this region was initialized using ::read(). |
| size_t _file_offset; // Data for this region starts at this offset in the archive file. |
| size_t _mapping_offset; // This encodes the requested address for this region to be mapped at runtime. |
| // However, the JVM may choose to map at an alternative location (e.g., for ASLR, |
| // or to adapt to the available ranges in the Java heap range). |
| // - For an RO/RW region, the requested address is: |
| // FileMapHeader::requested_base_address() + _mapping_offset |
| // - For a heap region, the requested address is: |
| // +UseCompressedOops: /*runtime*/ CompressedOops::base() + _mapping_offset |
| // -UseCompressedOops: FileMapHeader::heap_begin() + _mapping_offset |
| // See FileMapInfo::heap_region_requested_address(). |
| // - For bitmap regions, the _mapping_offset is always zero. The runtime address |
| // is picked by the OS. |
| size_t _used; // Number of bytes actually used by this region (excluding padding bytes added |
| // for alignment purposed. |
| size_t _oopmap_offset; // Bitmap for relocating oop fields in archived heap objects. |
| // (The base address is the bottom of the BM region) |
| size_t _oopmap_size_in_bits; |
| size_t _ptrmap_offset; // Bitmap for relocating native pointer fields in archived heap objects. |
| // (The base address is the bottom of the BM region). |
| size_t _ptrmap_size_in_bits; |
| char* _mapped_base; // Actually mapped address (NULL if this region is not mapped). |
| } CDSFileMapRegion; |
| |
| // This portion of the archive file header must remain unchanged for |
| // _version >= CDS_GENERIC_HEADER_SUPPORTED_MIN_VERSION (13). |
| // This makes it possible to read important information from a CDS archive created by |
| // a different version of HotSpot, so that we can automatically regenerate the archive as necessary. |
| typedef struct GenericCDSFileMapHeader { |
| unsigned int _magic; // identification of file type |
| int _crc; // header crc checksum, start from _base_archive_name_offset |
| int _version; // CURRENT_CDS_ARCHIVE_VERSION of the jdk that dumped the this archive |
| unsigned int _header_size; // total size of the header, in bytes |
| unsigned int _base_archive_name_offset; // offset where the base archive name is stored |
| // static archive: 0 |
| // dynamic archive: |
| // 0 for default base archive |
| // non-zero for non-default base archive |
| // (char*)this + _base_archive_name_offset |
| // points to a 0-terminated string for the base archive name |
| unsigned int _base_archive_name_size; // size of base archive name including ending '\0' |
| // static: 0 |
| // dynamic: |
| // 0 for default base archive |
| // non-zero for non-default base archive |
| |
| } GenericCDSFileMapHeader; |
| |
| // This type is used by the Serviceability Agent to access the contents of |
| // a memory-mapped CDS archive. |
| typedef struct CDSFileMapHeaderBase { |
| // We cannot inherit from GenericCDSFileMapHeader as this type may be used |
| // by both C and C++ code. |
| GenericCDSFileMapHeader _generic_header; |
| CDSFileMapRegion _regions[NUM_CDS_REGIONS]; |
| } CDSFileMapHeaderBase; |
| |
| #endif // SHARE_INCLUDE_CDS_H |
