1 /*
  2  * Copyright (c) 2012, 2024, 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_CDS_METASPACESHARED_HPP
 26 #define SHARE_CDS_METASPACESHARED_HPP
 27 
 28 #include "memory/allocation.hpp"
 29 #include "memory/memRegion.hpp"
 30 #include "memory/virtualspace.hpp"
 31 #include "oops/oop.hpp"
 32 #include "utilities/macros.hpp"
 33 
 34 class ArchiveBuilder;
 35 class ArchiveHeapInfo;
 36 class FileMapInfo;
 37 class Method;
 38 class outputStream;
 39 class SerializeClosure;
 40 
 41 template<class E> class Array;
 42 template<class E> class GrowableArray;
 43 
 44 enum MapArchiveResult {
 45   MAP_ARCHIVE_SUCCESS,
 46   MAP_ARCHIVE_MMAP_FAILURE,
 47   MAP_ARCHIVE_OTHER_FAILURE
 48 };
 49 
 50 class StaticArchiveBuilder;
 51 
 52 // Class Data Sharing Support
 53 class MetaspaceShared : AllStatic {
 54   static ReservedSpace _symbol_rs;  // used only during -Xshare:dump
 55   static VirtualSpace _symbol_vs;   // used only during -Xshare:dump
 56   static bool _archive_loading_failed;
 57   static bool _remapped_readwrite;
 58   static void* _shared_metaspace_static_top;
 59   static intx _relocation_delta;
 60   static char* _requested_base_address;
 61   static Array<Method*>* _archived_method_handle_intrinsics;
 62   static bool _use_optimized_module_handling;
 63 
 64  public:
 65   enum {
 66     // core archive spaces
 67     rw = 0,  // read-write shared space
 68     ro = 1,  // read-only shared space
 69     bm = 2,  // relocation bitmaps (freed after file mapping is finished)
 70     hp = 3,  // heap region
 71     cc = 4,  // cached code
 72     num_core_region = 2,       // rw and ro
 73     n_regions = 5              // total number of regions
 74   };
 75 
 76   static void prepare_for_dumping() NOT_CDS_RETURN;
 77   static void preload_and_dump() NOT_CDS_RETURN;
 78 #ifdef _LP64
 79   static void adjust_heap_sizes_for_dumping() NOT_CDS_JAVA_HEAP_RETURN;
 80 #endif
 81 
 82 private:
 83   static void preload_and_dump_impl(StaticArchiveBuilder& builder, TRAPS) NOT_CDS_RETURN;
 84   static void preload_classes(TRAPS) NOT_CDS_RETURN;
 85 
 86 public:
 87   static Symbol* symbol_rs_base() {
 88     return (Symbol*)_symbol_rs.base();
 89   }
 90 
 91   static void initialize_for_static_dump() NOT_CDS_RETURN;
 92   static void open_static_archive() NOT_CDS_RETURN;
 93   static void initialize_runtime_shared_and_meta_spaces() NOT_CDS_RETURN;
 94   static void post_initialize(TRAPS) NOT_CDS_RETURN;
 95 
 96   static void print_on(outputStream* st);
 97 
 98   static void set_archive_loading_failed() {
 99     _archive_loading_failed = true;
100   }
101 
102   static void initialize_shared_spaces() NOT_CDS_RETURN;
103 
104   // Return true if given address is in the shared metaspace regions (i.e., excluding the
105   // mapped heap region.)
106   static bool is_in_shared_metaspace(const void* p) {
107     return MetaspaceObj::is_shared((const MetaspaceObj*)p);
108   }
109 
110   static void set_shared_metaspace_range(void* base, void *static_top, void* top) NOT_CDS_RETURN;
111 
112   static bool is_shared_dynamic(void* p) NOT_CDS_RETURN_(false);
113   static bool is_shared_static(void* p) NOT_CDS_RETURN_(false);
114 
115   static void unrecoverable_loading_error(const char* message = nullptr);
116   static void unrecoverable_writing_error(const char* message = nullptr);
117 
118   static void make_method_handle_intrinsics_shareable() NOT_CDS_RETURN;
119   static void write_method_handle_intrinsics() NOT_CDS_RETURN;
120   static Array<Method*>* archived_method_handle_intrinsics() { return _archived_method_handle_intrinsics; }
121   static void serialize(SerializeClosure* sc) NOT_CDS_RETURN;
122 
123   // JVM/TI RedefineClasses() support:
124   // Remap the shared readonly space to shared readwrite, private if
125   // sharing is enabled. Simply returns true if sharing is not enabled
126   // or if the remapping has already been done by a prior call.
127   static bool remap_shared_readonly_as_readwrite() NOT_CDS_RETURN_(true);
128   static bool remapped_readwrite() {
129     CDS_ONLY(return _remapped_readwrite);
130     NOT_CDS(return false);
131   }
132 
133   static bool try_link_class(JavaThread* current, InstanceKlass* ik);
134   static void link_shared_classes(bool jcmd_request, TRAPS) NOT_CDS_RETURN;
135   static bool may_be_eagerly_linked(InstanceKlass* ik) NOT_CDS_RETURN_(false);
136 
137 #if INCLUDE_CDS
138   // Alignment for the 2 core CDS regions (RW/RO) only.
139   // (Heap region alignments are decided by GC).
140   static size_t core_region_alignment();
141   static void rewrite_nofast_bytecodes_and_calculate_fingerprints(Thread* thread, InstanceKlass* ik);
142   // print loaded classes names to file.
143   static void dump_loaded_classes(const char* file_name, TRAPS);
144 #endif
145 
146   // Allocate a block of memory from the temporary "symbol" region.
147   static char* symbol_space_alloc(size_t num_bytes);
148 
149   // This is the base address as specified by -XX:SharedBaseAddress during -Xshare:dump.
150   // Both the base/top archives are written using this as their base address.
151   //
152   // During static dump: _requested_base_address == SharedBaseAddress.
153   //
154   // During dynamic dump: _requested_base_address is not always the same as SharedBaseAddress:
155   // - SharedBaseAddress is used for *reading the base archive*. I.e., CompactHashtable uses
156   //   it to convert offsets to pointers to Symbols in the base archive.
157   //   The base archive may be mapped to an OS-selected address due to ASLR. E.g.,
158   //   you may have SharedBaseAddress == 0x00ff123400000000.
159   // - _requested_base_address is used for *writing the output archive*. It's usually
160   //   0x800000000 (unless it was set by -XX:SharedBaseAddress during -Xshare:dump).
161   static char* requested_base_address() {
162     return _requested_base_address;
163   }
164 
165   // Non-zero if the archive(s) need to be mapped a non-default location due to ASLR.
166   static intx relocation_delta() { return _relocation_delta; }
167 
168   static bool use_windows_memory_mapping() {
169     const bool is_windows = (NOT_WINDOWS(false) WINDOWS_ONLY(true));
170     //const bool is_windows = true; // enable this to allow testing the windows mmap semantics on Linux, etc.
171     return is_windows;
172   }
173 
174   // Can we skip some expensive operations related to modules?
175   static bool use_optimized_module_handling() { return NOT_CDS(false) CDS_ONLY(_use_optimized_module_handling); }
176   static void disable_optimized_module_handling() { _use_optimized_module_handling = false; }
177 
178 private:
179   static void read_extra_data(JavaThread* current, const char* filename) NOT_CDS_RETURN;
180   static void write_static_archive(ArchiveBuilder* builder, FileMapInfo *mapinfo, ArchiveHeapInfo* heap_info);
181   static void fork_and_dump_final_static_archive();
182   static FileMapInfo* open_dynamic_archive();
183   // use_requested_addr: If true (default), attempt to map at the address the
184   static MapArchiveResult map_archives(FileMapInfo* static_mapinfo, FileMapInfo* dynamic_mapinfo,
185                                        bool use_requested_addr);
186   static char* reserve_address_space_for_archives(FileMapInfo* static_mapinfo,
187                                                   FileMapInfo* dynamic_mapinfo,
188                                                   bool use_archive_base_addr,
189                                                   ReservedSpace& total_space_rs,
190                                                   ReservedSpace& archive_space_rs,
191                                                   ReservedSpace& class_space_rs);
192  static void release_reserved_spaces(ReservedSpace& total_space_rs,
193                                      ReservedSpace& archive_space_rs,
194                                      ReservedSpace& class_space_rs);
195   static MapArchiveResult map_archive(FileMapInfo* mapinfo, char* mapped_base_address, ReservedSpace rs);
196   static void unmap_archive(FileMapInfo* mapinfo);
197   static void get_default_classlist(char* default_classlist, const size_t buf_size);
198 };
199 #endif // SHARE_CDS_METASPACESHARED_HPP