/*

 * Copyright (c) 2012, 2018, 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.

 *

 */

#include "precompiled.hpp"

#include "jvm.h"

#include "classfile/classLoaderDataGraph.hpp"

#include "classfile/classListParser.hpp"

#include "classfile/classLoaderExt.hpp"

#include "classfile/dictionary.hpp"

#include "classfile/loaderConstraints.hpp"

#include "classfile/javaClasses.inline.hpp"

#include "classfile/placeholders.hpp"

#include "classfile/symbolTable.hpp"

#include "classfile/stringTable.hpp"

#include "classfile/systemDictionary.hpp"

#include "classfile/systemDictionaryShared.hpp"

#include "code/codeCache.hpp"

#include "interpreter/bytecodeStream.hpp"

#include "interpreter/bytecodes.hpp"

#include "logging/log.hpp"

#include "logging/logMessage.hpp"

#include "memory/filemap.hpp"

#include "memory/heapShared.inline.hpp"

#include "memory/metaspace.hpp"

#include "memory/metaspaceClosure.hpp"

#include "memory/metaspaceShared.hpp"

#include "memory/resourceArea.hpp"

#include "oops/compressedOops.inline.hpp"

#include "oops/instanceClassLoaderKlass.hpp"

#include "oops/instanceMirrorKlass.hpp"

#include "oops/instanceRefKlass.hpp"

#include "oops/objArrayKlass.hpp"

#include "oops/objArrayOop.hpp"

#include "oops/oop.inline.hpp"

#include "oops/typeArrayKlass.hpp"

#include "prims/jvmtiRedefineClasses.hpp"

#include "runtime/handles.inline.hpp"

#include "runtime/os.hpp"

#include "runtime/safepointVerifiers.hpp"

#include "runtime/signature.hpp"

#include "runtime/timerTrace.hpp"

#include "runtime/vmThread.hpp"

#include "utilities/align.hpp"

#include "utilities/bitMap.hpp"

#include "utilities/defaultStream.hpp"

#include "utilities/hashtable.inline.hpp"

#if INCLUDE_G1GC

#include "gc/g1/g1CollectedHeap.hpp"

#endif

ReservedSpace MetaspaceShared::_shared_rs;

VirtualSpace MetaspaceShared::_shared_vs;

MetaspaceSharedStats MetaspaceShared::_stats;

bool MetaspaceShared::_has_error_classes;

bool MetaspaceShared::_archive_loading_failed = false;

bool MetaspaceShared::_remapped_readwrite = false;

address MetaspaceShared::_cds_i2i_entry_code_buffers = NULL;

size_t MetaspaceShared::_cds_i2i_entry_code_buffers_size = 0;

size_t MetaspaceShared::_core_spaces_size = 0;

// The CDS archive is divided into the following regions:

//     mc  - misc code (the method entry trampolines)

//     rw  - read-write metadata

//     ro  - read-only metadata and read-only tables

//     md  - misc data (the c++ vtables)

//     od  - optional data (original class files)

//

//     ca0 - closed archive heap space #0

//     ca1 - closed archive heap space #1 (may be empty)

//     oa0 - open archive heap space #0

//     oa1 - open archive heap space #1 (may be empty)

//

// The mc, rw, ro, md and od regions are linearly allocated, starting from

// SharedBaseAddress, in the order of mc->rw->ro->md->od. The size of these 5 regions

// are page-aligned, and there's no gap between any consecutive regions.

//

// These 5 regions are populated in the following steps:

// [1] All classes are loaded in MetaspaceShared::preload_classes(). All metadata are

//     temporarily allocated outside of the shared regions. Only the method entry

//     trampolines are written into the mc region.

// [2] ArchiveCompactor copies RW metadata into the rw region.

// [3] ArchiveCompactor copies RO metadata into the ro region.

// [4] SymbolTable, StringTable, SystemDictionary, and a few other read-only data

//     are copied into the ro region as read-only tables.

// [5] C++ vtables are copied into the md region.

// [6] Original class files are copied into the od region.

//

// The s0/s1 and oa0/oa1 regions are populated inside HeapShared::archive_java_heap_objects.

// Their layout is independent of the other 5 regions.

class DumpRegion {

private:

  const char* _name;

  char* _base;

  char* _top;

  char* _end;

  bool _is_packed;

  char* expand_top_to(char* newtop) {

    assert(is_allocatable(), "must be initialized and not packed");

    assert(newtop >= _top, "must not grow backwards");

    if (newtop > _end) {

      MetaspaceShared::report_out_of_space(_name, newtop - _top);

      ShouldNotReachHere();

    }

    uintx delta = MetaspaceShared::object_delta_uintx(newtop);

    if (delta > MAX_SHARED_DELTA) {

      // This is just a sanity check and should not appear in any real world usage. This

      // happens only if you allocate more than 2GB of shared objects and would require

      // millions of shared classes.

      vm_exit_during_initialization("Out of memory in the CDS archive",

                                    "Please reduce the number of shared classes.");

    }

    MetaspaceShared::commit_shared_space_to(newtop);

    _top = newtop;

    return _top;

  }

public:

  DumpRegion(const char* name) : _name(name), _base(NULL), _top(NULL), _end(NULL), _is_packed(false) {}

  char* allocate(size_t num_bytes, size_t alignment=BytesPerWord) {

    char* p = (char*)align_up(_top, alignment);

    char* newtop = p + align_up(num_bytes, alignment);

    expand_top_to(newtop);

    memset(p, 0, newtop - p);

    return p;

  }

  void append_intptr_t(intptr_t n) {

    assert(is_aligned(_top, sizeof(intptr_t)), "bad alignment");

    intptr_t *p = (intptr_t*)_top;

    char* newtop = _top + sizeof(intptr_t);

    expand_top_to(newtop);

    *p = n;

  }

  char* base()      const { return _base;        }

  char* top()       const { return _top;         }

  char* end()       const { return _end;         }

  size_t reserved() const { return _end - _base; }

  size_t used()     const { return _top - _base; }

  bool is_packed()  const { return _is_packed;   }

  bool is_allocatable() const {

    return !is_packed() && _base != NULL;

  }

  void print(size_t total_bytes) const {

    tty->print_cr("%-3s space: " SIZE_FORMAT_W(9) " [ %4.1f%% of total] out of " SIZE_FORMAT_W(9) " bytes [%5.1f%% used] at " INTPTR_FORMAT,

                  _name, used(), percent_of(used(), total_bytes), reserved(), percent_of(used(), reserved()), p2i(_base));

  }

  void print_out_of_space_msg(const char* failing_region, size_t needed_bytes) {

    tty->print("[%-8s] " PTR_FORMAT " - " PTR_FORMAT " capacity =%9d, allocated =%9d",

               _name, p2i(_base), p2i(_top), int(_end - _base), int(_top - _base));

    if (strcmp(_name, failing_region) == 0) {

      tty->print_cr(" required = %d", int(needed_bytes));

    } else {

      tty->cr();

    }

  }

  void init(const ReservedSpace* rs) {

    _base = _top = rs->base();

    _end = rs->end();

  }

  void init(char* b, char* t, char* e) {

    _base = b;

    _top = t;

    _end = e;

  }

  void pack(DumpRegion* next = NULL) {

    assert(!is_packed(), "sanity");

    _end = (char*)align_up(_top, Metaspace::reserve_alignment());

    _is_packed = true;

    if (next != NULL) {

      next->_base = next->_top = this->_end;

      next->_end = MetaspaceShared::shared_rs()->end();

    }

  }

  bool contains(char* p) {

    return base() <= p && p < top();

  }

};

DumpRegion _mc_region("mc"), _ro_region("ro"), _rw_region("rw"), _md_region("md"), _od_region("od");

size_t _total_closed_archive_region_size = 0, _total_open_archive_region_size = 0;

char* MetaspaceShared::misc_code_space_alloc(size_t num_bytes) {

  return _mc_region.allocate(num_bytes);

}

char* MetaspaceShared::read_only_space_alloc(size_t num_bytes) {

  return _ro_region.allocate(num_bytes);

}

char* MetaspaceShared::read_only_space_top() {

  return _ro_region.top();

}

void MetaspaceShared::initialize_runtime_shared_and_meta_spaces() {

  assert(UseSharedSpaces, "Must be called when UseSharedSpaces is enabled");

  // If using shared space, open the file that contains the shared space

  // and map in the memory before initializing the rest of metaspace (so

  // the addresses don't conflict)

  address cds_address = NULL;

  FileMapInfo* mapinfo = new FileMapInfo();

  // Open the shared archive file, read and validate the header. If

  // initialization fails, shared spaces [UseSharedSpaces] are

  // disabled and the file is closed.

  // Map in spaces now also

  if (mapinfo->initialize() && map_shared_spaces(mapinfo)) {

    size_t cds_total = core_spaces_size();

    cds_address = (address)mapinfo->region_addr(0);

#ifdef _LP64

    if (Metaspace::using_class_space()) {

      char* cds_end = (char*)(cds_address + cds_total);

      cds_end = (char *)align_up(cds_end, Metaspace::reserve_alignment());

      // If UseCompressedClassPointers is set then allocate the metaspace area

      // above the heap and above the CDS area (if it exists).

      Metaspace::allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address);

      // map_heap_regions() compares the current narrow oop and klass encodings

      // with the archived ones, so it must be done after all encodings are determined.

      mapinfo->map_heap_regions();

    }

    Universe::set_narrow_klass_range(CompressedClassSpaceSize);

#endif // _LP64

  } else {

    assert(!mapinfo->is_open() && !UseSharedSpaces,

           "archive file not closed or shared spaces not disabled.");

  }

}

void MetaspaceShared::initialize_dumptime_shared_and_meta_spaces() {

  assert(DumpSharedSpaces, "should be called for dump time only");

  const size_t reserve_alignment = Metaspace::reserve_alignment();

  bool large_pages = false; // No large pages when dumping the CDS archive.

  char* shared_base = (char*)align_up((char*)SharedBaseAddress, reserve_alignment);

#ifdef _LP64

  // On 64-bit VM, the heap and class space layout will be the same as if

  // you're running in -Xshare:on mode:

  //

  //                              +-- SharedBaseAddress (default = 0x800000000)

  //                              v

  // +-..---------+---------+ ... +----+----+----+----+----+---------------+

  // |    Heap    | Archive |     | MC | RW | RO | MD | OD | class space   |

  // +-..---------+---------+ ... +----+----+----+----+----+---------------+

  // |<--   MaxHeapSize  -->|     |<-- UnscaledClassSpaceMax = 4GB ------->|

  //

  const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);

  const size_t cds_total = align_down(UnscaledClassSpaceMax, reserve_alignment);

#else

  // We don't support archives larger than 256MB on 32-bit due to limited virtual address space.

  size_t cds_total = align_down(256*M, reserve_alignment);

#endif

  // First try to reserve the space at the specified SharedBaseAddress.

  _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages, shared_base);

  if (_shared_rs.is_reserved()) {

    assert(shared_base == 0 || _shared_rs.base() == shared_base, "should match");

  } else {

    // Get a mmap region anywhere if the SharedBaseAddress fails.

    _shared_rs = ReservedSpace(cds_total, reserve_alignment, large_pages);

  }

  if (!_shared_rs.is_reserved()) {

    vm_exit_during_initialization("Unable to reserve memory for shared space",

                                  err_msg(SIZE_FORMAT " bytes.", cds_total));

  }

#ifdef _LP64

  // During dump time, we allocate 4GB (UnscaledClassSpaceMax) of space and split it up:

  // + The upper 1 GB is used as the "temporary compressed class space" -- preload_classes()

  //   will store Klasses into this space.

  // + The lower 3 GB is used for the archive -- when preload_classes() is done,

  //   ArchiveCompactor will copy the class metadata into this space, first the RW parts,

  //   then the RO parts.

  assert(UseCompressedOops && UseCompressedClassPointers,

      "UseCompressedOops and UseCompressedClassPointers must be set");

  size_t max_archive_size = align_down(cds_total * 3 / 4, reserve_alignment);

  ReservedSpace tmp_class_space = _shared_rs.last_part(max_archive_size);

  CompressedClassSpaceSize = align_down(tmp_class_space.size(), reserve_alignment);

  _shared_rs = _shared_rs.first_part(max_archive_size);

  // Set up compress class pointers.

  Universe::set_narrow_klass_base((address)_shared_rs.base());

  // Set narrow_klass_shift to be LogKlassAlignmentInBytes. This is consistent

  // with AOT.

  Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes);

  // Set the range of klass addresses to 4GB.

  Universe::set_narrow_klass_range(cds_total);

  Metaspace::initialize_class_space(tmp_class_space);

  log_info(cds)("narrow_klass_base = " PTR_FORMAT ", narrow_klass_shift = %d",

                p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift());

  log_info(cds)("Allocated temporary class space: " SIZE_FORMAT " bytes at " PTR_FORMAT,

                CompressedClassSpaceSize, p2i(tmp_class_space.base()));

#endif

  // Start with 0 committed bytes. The memory will be committed as needed by

  // MetaspaceShared::commit_shared_space_to().

  if (!_shared_vs.initialize(_shared_rs, 0)) {

    vm_exit_during_initialization("Unable to allocate memory for shared space");

  }

  _mc_region.init(&_shared_rs);

  SharedBaseAddress = (size_t)_shared_rs.base();

  tty->print_cr("Allocated shared space: " SIZE_FORMAT " bytes at " PTR_FORMAT,

                _shared_rs.size(), p2i(_shared_rs.base()));

}

// Called by universe_post_init()

void MetaspaceShared::post_initialize(TRAPS) {

  if (UseSharedSpaces) {

    int size = FileMapInfo::get_number_of_shared_paths();

    if (size > 0) {

      SystemDictionaryShared::allocate_shared_data_arrays(size, THREAD);

      FileMapHeader* header = FileMapInfo::current_info()->header();

      ClassLoaderExt::init_paths_start_index(header->_app_class_paths_start_index);

      ClassLoaderExt::init_app_module_paths_start_index(header->_app_module_paths_start_index);

    }

  }

}

static GrowableArray<Handle>* _extra_interned_strings = NULL;

void MetaspaceShared::read_extra_data(const char* filename, TRAPS) {

  _extra_interned_strings = new (ResourceObj::C_HEAP, mtInternal)GrowableArray<Handle>(10000, true);

  HashtableTextDump reader(filename);

  reader.check_version("VERSION: 1.0");

  while (reader.remain() > 0) {

    int utf8_length;

    int prefix_type = reader.scan_prefix(&utf8_length);

    ResourceMark rm(THREAD);

    if (utf8_length == 0x7fffffff) {

      // buf_len will overflown 32-bit value.

      vm_exit_during_initialization(err_msg("string length too large: %d", utf8_length));

    }

    int buf_len = utf8_length+1;

    char* utf8_buffer = NEW_RESOURCE_ARRAY(char, buf_len);

    reader.get_utf8(utf8_buffer, utf8_length);

    utf8_buffer[utf8_length] = '\0';

    if (prefix_type == HashtableTextDump::SymbolPrefix) {

      SymbolTable::new_permanent_symbol(utf8_buffer, THREAD);

    } else{

      assert(prefix_type == HashtableTextDump::StringPrefix, "Sanity");

      oop s = StringTable::intern(utf8_buffer, THREAD);

      if (HAS_PENDING_EXCEPTION) {

        log_warning(cds, heap)("[line %d] extra interned string allocation failed; size too large: %d",

                               reader.last_line_no(), utf8_length);

        CLEAR_PENDING_EXCEPTION;

      } else {

#if INCLUDE_G1GC

        if (UseG1GC) {

          typeArrayOop body = java_lang_String::value(s);

          const HeapRegion* hr = G1CollectedHeap::heap()->heap_region_containing(body);

          if (hr->is_humongous()) {

            // Don't keep it alive, so it will be GC'ed before we dump the strings, in order

            // to maximize free heap space and minimize fragmentation.

            log_warning(cds, heap)("[line %d] extra interned string ignored; size too large: %d",

                                reader.last_line_no(), utf8_length);

            continue;

          }

        }

#endif

        // Interned strings are GC'ed if there are no references to it, so let's

        // add a reference to keep this string alive.

        assert(s != NULL, "must succeed");

        Handle h(THREAD, s);

        _extra_interned_strings->append(h);

      }

    }

  }

}

void MetaspaceShared::commit_shared_space_to(char* newtop) {

  assert(DumpSharedSpaces, "dump-time only");

  char* base = _shared_rs.base();

  size_t need_committed_size = newtop - base;

  size_t has_committed_size = _shared_vs.committed_size();

  if (need_committed_size < has_committed_size) {

    return;

  }

  size_t min_bytes = need_committed_size - has_committed_size;

  size_t preferred_bytes = 1 * M;

  size_t uncommitted = _shared_vs.reserved_size() - has_committed_size;

  size_t commit = MAX2(min_bytes, preferred_bytes);

  assert(commit <= uncommitted, "sanity");

  bool result = _shared_vs.expand_by(commit, false);

  if (!result) {

    vm_exit_during_initialization(err_msg("Failed to expand shared space to " SIZE_FORMAT " bytes",

                                          need_committed_size));

  }

  log_info(cds)("Expanding shared spaces by " SIZE_FORMAT_W(7) " bytes [total " SIZE_FORMAT_W(9)  " bytes ending at %p]",

                commit, _shared_vs.actual_committed_size(), _shared_vs.high());

}

// Read/write a data stream for restoring/preserving metadata pointers and

// miscellaneous data from/to the shared archive file.

void MetaspaceShared::serialize(SerializeClosure* soc) {

  int tag = 0;

  soc->do_tag(--tag);

  // Verify the sizes of various metadata in the system.

  soc->do_tag(sizeof(Method));

  soc->do_tag(sizeof(ConstMethod));

  soc->do_tag(arrayOopDesc::base_offset_in_bytes(T_BYTE));

  soc->do_tag(sizeof(ConstantPool));

  soc->do_tag(sizeof(ConstantPoolCache));

  soc->do_tag(objArrayOopDesc::base_offset_in_bytes());

  soc->do_tag(typeArrayOopDesc::base_offset_in_bytes(T_BYTE));

  soc->do_tag(sizeof(Symbol));

  // Dump/restore miscellaneous metadata.

  Universe::serialize(soc);

  soc->do_tag(--tag);

  // Dump/restore references to commonly used names and signatures.

  vmSymbols::serialize(soc);

  soc->do_tag(--tag);

  // Dump/restore the symbol/string/subgraph_info tables

  SymbolTable::serialize_shared_table_header(soc);

  StringTable::serialize_shared_table_header(soc);

  HeapShared::serialize_subgraph_info_table_header(soc);

  SystemDictionaryShared::serialize_dictionary_headers(soc);

  JavaClasses::serialize_offsets(soc);

  InstanceMirrorKlass::serialize_offsets(soc);

  soc->do_tag(--tag);

  soc->do_tag(666);

}

address MetaspaceShared::cds_i2i_entry_code_buffers(size_t total_size) {

  if (DumpSharedSpaces) {

    if (_cds_i2i_entry_code_buffers == NULL) {

      _cds_i2i_entry_code_buffers = (address)misc_code_space_alloc(total_size);

      _cds_i2i_entry_code_buffers_size = total_size;

    }

  } else if (UseSharedSpaces) {

    assert(_cds_i2i_entry_code_buffers != NULL, "must already been initialized");

  } else {

    return NULL;

  }

  assert(_cds_i2i_entry_code_buffers_size == total_size, "must not change");

  return _cds_i2i_entry_code_buffers;

}

// Global object for holding classes that have been loaded.  Since this

// is run at a safepoint just before exit, this is the entire set of classes.

static GrowableArray<Klass*>* _global_klass_objects;