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.
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 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 class StaticArchiveBuilder;
 41 
 42 template<class E> class Array;
 43 template<class E> class GrowableArray;
 44 
 45 enum MapArchiveResult {
 46   MAP_ARCHIVE_SUCCESS,
 47   MAP_ARCHIVE_MMAP_FAILURE,
 48   MAP_ARCHIVE_OTHER_FAILURE
 49 };
 50 
 51 class StaticArchiveBuilder;
 52 
 53 // Class Data Sharing Support
 54 class MetaspaceShared : AllStatic {
 55   static ReservedSpace _symbol_rs;  // used only during -Xshare:dump
 56   static VirtualSpace _symbol_vs;   // used only during -Xshare:dump
 57   static bool _archive_loading_failed;
 58   static bool _remapped_readwrite;
 59   static void* _shared_metaspace_static_top;
 60   static intx _relocation_delta;
 61   static char* _requested_base_address;
 62   static Array<Method*>* _archived_method_handle_intrinsics;
 63   static bool _use_optimized_module_handling;
 64 
 65  public:
 66   enum {
 67     // core archive spaces
 68     rw = 0,  // read-write shared space
 69     ro = 1,  // read-only shared space
 70     bm = 2,  // relocation bitmaps (freed after file mapping is finished)
 71     hp = 3,  // heap region
 72     cc = 4,  // cached code
 73     num_core_region = 2,       // rw and ro
 74     n_regions = 5              // total number of regions
 75   };
 76 
 77   static void prepare_for_dumping() NOT_CDS_RETURN;
 78   static void preload_and_dump(TRAPS) NOT_CDS_RETURN;
 79 #ifdef _LP64
 80   static void adjust_heap_sizes_for_dumping() NOT_CDS_JAVA_HEAP_RETURN;
 81 #endif
 82 
 83 private:
 84   static void preload_and_dump_impl(StaticArchiveBuilder& builder, TRAPS) NOT_CDS_RETURN;
 85   static void preload_classes(TRAPS) NOT_CDS_RETURN;
 86 
 87 public:
 88   static Symbol* symbol_rs_base() {
 89     return (Symbol*)_symbol_rs.base();
 90   }
 91 
 92   static void initialize_for_static_dump() NOT_CDS_RETURN;
 93   static void open_static_archive() NOT_CDS_RETURN;
 94   static void initialize_runtime_shared_and_meta_spaces() NOT_CDS_RETURN;
 95   static void post_initialize(TRAPS) NOT_CDS_RETURN;
 96 
 97   static void print_on(outputStream* st);
 98 
 99   static void set_archive_loading_failed() {
100     _archive_loading_failed = true;
101   }
102 
103   static void initialize_shared_spaces() NOT_CDS_RETURN;
104 
105   // Return true if given address is in the shared metaspace regions (i.e., excluding the
106   // mapped heap region.)
107   static bool is_in_shared_metaspace(const void* p) {
108     return MetaspaceObj::is_shared((const MetaspaceObj*)p);
109   }
110 
111   static void set_shared_metaspace_range(void* base, void *static_top, void* top) NOT_CDS_RETURN;
112 
113   static bool is_shared_dynamic(void* p) NOT_CDS_RETURN_(false);
114   static bool is_shared_static(void* p) NOT_CDS_RETURN_(false);
115 
116   static void unrecoverable_loading_error(const char* message = nullptr);
117   static void unrecoverable_writing_error(const char* message = nullptr);
118   static void writing_error(const char* message = nullptr);
119 
120   static void make_method_handle_intrinsics_shareable() NOT_CDS_RETURN;
121   static void write_method_handle_intrinsics() NOT_CDS_RETURN;
122   static Array<Method*>* archived_method_handle_intrinsics() { return _archived_method_handle_intrinsics; }
123   static void serialize(SerializeClosure* sc) NOT_CDS_RETURN;
124 
125   // JVM/TI RedefineClasses() support:
126   // Remap the shared readonly space to shared readwrite, private if
127   // sharing is enabled. Simply returns true if sharing is not enabled
128   // or if the remapping has already been done by a prior call.
129   static bool remap_shared_readonly_as_readwrite() NOT_CDS_RETURN_(true);
130   static bool remapped_readwrite() {
131     CDS_ONLY(return _remapped_readwrite);
132     NOT_CDS(return false);
133   }
134 
135   static bool try_link_class(JavaThread* current, InstanceKlass* ik);
136   static void link_shared_classes(bool jcmd_request, TRAPS) NOT_CDS_RETURN;

137   static bool may_be_eagerly_linked(InstanceKlass* ik) NOT_CDS_RETURN_(false);
138 
139 #if INCLUDE_CDS
140   // Alignment for the 2 core CDS regions (RW/RO) only.
141   // (Heap region alignments are decided by GC).
142   static size_t core_region_alignment();
143   static void rewrite_nofast_bytecodes_and_calculate_fingerprints(Thread* thread, InstanceKlass* ik);
144   // print loaded classes names to file.
145   static void dump_loaded_classes(const char* file_name, TRAPS);
146 #endif
147 
148   // Allocate a block of memory from the temporary "symbol" region.
149   static char* symbol_space_alloc(size_t num_bytes);
150 
151   // This is the base address as specified by -XX:SharedBaseAddress during -Xshare:dump.
152   // Both the base/top archives are written using this as their base address.
153   //
154   // During static dump: _requested_base_address == SharedBaseAddress.
155   //
156   // During dynamic dump: _requested_base_address is not always the same as SharedBaseAddress:
157   // - SharedBaseAddress is used for *reading the base archive*. I.e., CompactHashtable uses
158   //   it to convert offsets to pointers to Symbols in the base archive.
159   //   The base archive may be mapped to an OS-selected address due to ASLR. E.g.,
160   //   you may have SharedBaseAddress == 0x00ff123400000000.
161   // - _requested_base_address is used for *writing the output archive*. It's usually
162   //   0x800000000 (unless it was set by -XX:SharedBaseAddress during -Xshare:dump).
163   static char* requested_base_address() {
164     return _requested_base_address;
165   }
166 
167   // Non-zero if the archive(s) need to be mapped a non-default location due to ASLR.
168   static intx relocation_delta() { return _relocation_delta; }
169 
170   static bool use_windows_memory_mapping() {
171     const bool is_windows = (NOT_WINDOWS(false) WINDOWS_ONLY(true));
172     //const bool is_windows = true; // enable this to allow testing the windows mmap semantics on Linux, etc.
173     return is_windows;
174   }
175 
176   // Can we skip some expensive operations related to modules?
177   static bool use_optimized_module_handling() { return NOT_CDS(false) CDS_ONLY(_use_optimized_module_handling); }
178   static void disable_optimized_module_handling() { _use_optimized_module_handling = false; }
179 
180 private:
181   static void read_extra_data(JavaThread* current, const char* filename) NOT_CDS_RETURN;
182   static void fork_and_dump_final_static_archive();
183   static bool write_static_archive(ArchiveBuilder* builder, FileMapInfo* map_info, ArchiveHeapInfo* heap_info);

184   static FileMapInfo* open_dynamic_archive();
185   // use_requested_addr: If true (default), attempt to map at the address the
186   static MapArchiveResult map_archives(FileMapInfo* static_mapinfo, FileMapInfo* dynamic_mapinfo,
187                                        bool use_requested_addr);
188   static char* reserve_address_space_for_archives(FileMapInfo* static_mapinfo,
189                                                   FileMapInfo* dynamic_mapinfo,
190                                                   bool use_archive_base_addr,
191                                                   ReservedSpace& total_space_rs,
192                                                   ReservedSpace& archive_space_rs,
193                                                   ReservedSpace& class_space_rs);
194  static void release_reserved_spaces(ReservedSpace& total_space_rs,
195                                      ReservedSpace& archive_space_rs,
196                                      ReservedSpace& class_space_rs);
197   static MapArchiveResult map_archive(FileMapInfo* mapinfo, char* mapped_base_address, ReservedSpace rs);
198   static void unmap_archive(FileMapInfo* mapinfo);
199   static void get_default_classlist(char* default_classlist, const size_t buf_size);
200 };
201 #endif // SHARE_CDS_METASPACESHARED_HPP
--- EOF ---