/*

 * Copyright (c) 2012, 2019, 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_MEMORY_METASPACESHARED_HPP

#define SHARE_MEMORY_METASPACESHARED_HPP

#include "classfile/compactHashtable.hpp"

#include "memory/allocation.hpp"

#include "memory/memRegion.hpp"

#include "memory/virtualspace.hpp"

#include "oops/oop.hpp"

#include "utilities/exceptions.hpp"

#include "utilities/macros.hpp"

#include "utilities/resourceHash.hpp"

#define MAX_SHARED_DELTA                (0x7FFFFFFF)

class FileMapInfo;

class MetaspaceSharedStats {

public:

  MetaspaceSharedStats() {

    memset(this, 0, sizeof(*this));

  }

  CompactHashtableStats symbol;

  CompactHashtableStats string;

};

#if INCLUDE_CDS

class DumpRegion {

private:

  const char* _name;

  char* _base;

  char* _top;

  char* _end;

  bool _is_packed;

public:

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

  char* expand_top_to(char* newtop);

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

  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;

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

  void init(const ReservedSpace* rs, char* base) {

    if (base == NULL) {

      base = rs->base();

    }

    assert(rs->contains(base), "must be");

    _base = _top = base;

    _end = rs->end();

  }

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

    _base = b;

    _top = t;

    _end = e;

  }

  void pack(DumpRegion* next = NULL);

  bool contains(char* p) {

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

  }

};

// Closure for serializing initialization data out to a data area to be

// written to the shared file.

class WriteClosure : public SerializeClosure {

private:

  DumpRegion* _dump_region;

public:

  WriteClosure(DumpRegion* r) {

    _dump_region = r;

  }

  void do_ptr(void** p) {

    _dump_region->append_intptr_t((intptr_t)*p);

  }

  void do_u4(u4* p) {

    void* ptr = (void*)(uintx(*p));

    do_ptr(&ptr);

  }

  void do_bool(bool *p) {

    void* ptr = (void*)(uintx(*p));

    do_ptr(&ptr);

  }

  void do_tag(int tag) {

    _dump_region->append_intptr_t((intptr_t)tag);

  }

  void do_oop(oop* o);

  void do_region(u_char* start, size_t size);

  bool reading() const { return false; }

};

// Closure for serializing initialization data in from a data area

// (ptr_array) read from the shared file.

class ReadClosure : public SerializeClosure {

private:

  intptr_t** _ptr_array;

  inline intptr_t nextPtr() {

    return *(*_ptr_array)++;

  }

public:

  ReadClosure(intptr_t** ptr_array) { _ptr_array = ptr_array; }

  void do_ptr(void** p);

  void do_u4(u4* p);

  void do_bool(bool *p);

  void do_tag(int tag);

  void do_oop(oop *p);

  void do_region(u_char* start, size_t size);

  bool reading() const { return true; }

};

#endif

// Class Data Sharing Support

class MetaspaceShared : AllStatic {

  // CDS support

  static ReservedSpace _shared_rs;

  static VirtualSpace _shared_vs;

  static int _max_alignment;

  static MetaspaceSharedStats _stats;

  static bool _has_error_classes;

  static bool _archive_loading_failed;

  static bool _remapped_readwrite;

  static address _i2i_entry_code_buffers;

  static size_t  _i2i_entry_code_buffers_size;

  static size_t  _core_spaces_size;

  static void* _shared_metaspace_static_top;

 public:

  enum {

    // core archive spaces

    mc = 0,  // miscellaneous code for method trampolines

    rw = 1,  // read-write shared space in the heap

    ro = 2,  // read-only shared space in the heap

    md = 3,  // miscellaneous data for initializing tables, etc.

    num_core_spaces = 4, // number of non-string regions

    num_non_heap_spaces = 4,

    // mapped java heap regions

    first_closed_archive_heap_region = md + 1,

    max_closed_archive_heap_region = 2,

    last_closed_archive_heap_region = first_closed_archive_heap_region + max_closed_archive_heap_region - 1,

    first_open_archive_heap_region = last_closed_archive_heap_region + 1,

    max_open_archive_heap_region = 2,

    last_open_archive_heap_region = first_open_archive_heap_region + max_open_archive_heap_region - 1,

    last_valid_region = last_open_archive_heap_region,

    n_regions =  last_valid_region + 1 // total number of regions

  };

  static void prepare_for_dumping() NOT_CDS_RETURN;

  static void preload_and_dump(TRAPS) NOT_CDS_RETURN;

  static int preload_classes(const char * class_list_path,

                             TRAPS) NOT_CDS_RETURN_(0);

  static GrowableArray<Klass*>* collected_klasses();

  static ReservedSpace* shared_rs() {

    CDS_ONLY(return &_shared_rs);

    NOT_CDS(return NULL);

  }

  static void commit_shared_space_to(char* newtop) NOT_CDS_RETURN;

  static size_t core_spaces_size() {

    assert(DumpSharedSpaces || UseSharedSpaces, "sanity");

    assert(_core_spaces_size != 0, "sanity");

    return _core_spaces_size;

  }

  static void initialize_dumptime_shared_and_meta_spaces() NOT_CDS_RETURN;

  static void initialize_runtime_shared_and_meta_spaces() NOT_CDS_RETURN;

  static char* initialize_dynamic_runtime_shared_spaces(

                     char* static_start, char* static_end) NOT_CDS_RETURN_(NULL);

  static void post_initialize(TRAPS) NOT_CDS_RETURN;

  // Delta of this object from SharedBaseAddress

  static uintx object_delta_uintx(void* obj);

  static u4 object_delta_u4(void* obj) {

    // offset is guaranteed to be less than MAX_SHARED_DELTA in DumpRegion::expand_top_to()

    uintx deltax = object_delta_uintx(obj);

    guarantee(deltax <= MAX_SHARED_DELTA, "must be 32-bit offset");

    return (u4)deltax;

  }

  static void set_archive_loading_failed() {

    _archive_loading_failed = true;

  }

  static bool map_shared_spaces(FileMapInfo* mapinfo) NOT_CDS_RETURN_(false);

  static void initialize_shared_spaces() NOT_CDS_RETURN;

  // Return true if given address is in the shared metaspace regions (i.e., excluding any

  // mapped shared heap regions.)

  static bool is_in_shared_metaspace(const void* p) {

    // If no shared metaspace regions are mapped, MetaspceObj::_shared_metaspace_{base,top} will

    // both be NULL and all values of p will be rejected quickly.

    return (p < MetaspaceObj::shared_metaspace_top() && p >= MetaspaceObj::shared_metaspace_base());

  }

  static address shared_metaspace_top() {

    return (address)MetaspaceObj::shared_metaspace_top();

  }

  static void set_shared_metaspace_range(void* base, void* top) NOT_CDS_RETURN;

  // Return true if given address is in the shared region corresponding to the idx

  static bool is_in_shared_region(const void* p, int idx) NOT_CDS_RETURN_(false);

  static bool is_in_trampoline_frame(address addr) NOT_CDS_RETURN_(false);

  static bool is_shared_dynamic(void* p) NOT_CDS_RETURN_(false);

  static void allocate_cpp_vtable_clones();

  static intptr_t* clone_cpp_vtables(intptr_t* p);

  static void zero_cpp_vtable_clones_for_writing();

  static void patch_cpp_vtable_pointers();

  static void serialize_cloned_cpp_vtptrs(SerializeClosure* sc);

  static bool is_valid_shared_method(const Method* m) NOT_CDS_RETURN_(false);

  static void serialize(SerializeClosure* sc) NOT_CDS_RETURN;

  static MetaspaceSharedStats* stats() {

    return &_stats;

  }

  static void report_out_of_space(const char* name, size_t needed_bytes);

  // JVM/TI RedefineClasses() support:

  // Remap the shared readonly space to shared readwrite, private if

  // sharing is enabled. Simply returns true if sharing is not enabled

  // or if the remapping has already been done by a prior call.

  static bool remap_shared_readonly_as_readwrite() NOT_CDS_RETURN_(true);

  static bool remapped_readwrite() {

    CDS_ONLY(return _remapped_readwrite);

    NOT_CDS(return false);

  }

  static bool try_link_class(InstanceKlass* ik, TRAPS);

  static void link_and_cleanup_shared_classes(TRAPS);

#if INCLUDE_CDS

  static ReservedSpace* reserve_shared_rs(size_t size, size_t alignment,

                                          bool large, char* requested_address);

  static void init_shared_dump_space(DumpRegion* first_space, address first_space_bottom = NULL);

  static DumpRegion* misc_code_dump_space();

  static DumpRegion* read_write_dump_space();

  static DumpRegion* read_only_dump_space();

  static void pack_dump_space(DumpRegion* current, DumpRegion* next,

                              ReservedSpace* rs);

#endif

  // Allocate a block of memory from the "mc", "ro", or "rw" regions.

  static char* misc_code_space_alloc(size_t num_bytes);

  static char* read_only_space_alloc(size_t num_bytes);

  template <typename T>

  static Array<T>* new_ro_array(int length) {

#if INCLUDE_CDS

    size_t byte_size = Array<T>::byte_sizeof(length, sizeof(T));

    Array<T>* array = (Array<T>*)read_only_space_alloc(byte_size);

    array->initialize(length);

    return array;

#else

    return NULL;

#endif

  }

  template <typename T>

  static size_t ro_array_bytesize(int length) {

    size_t byte_size = Array<T>::byte_sizeof(length, sizeof(T));

    return align_up(byte_size, BytesPerWord);

  }

  static address i2i_entry_code_buffers(size_t total_size);

  static address i2i_entry_code_buffers() {

    return _i2i_entry_code_buffers;

  }

  static size_t i2i_entry_code_buffers_size() {

    return _i2i_entry_code_buffers_size;

  }

  static void relocate_klass_ptr(oop o);

  static Klass* get_relocated_klass(Klass *k);

  static intptr_t* fix_cpp_vtable_for_dynamic_archive(MetaspaceObj::Type msotype, address obj);

private:

  static void read_extra_data(const char* filename, TRAPS) NOT_CDS_RETURN;

};

#endif // SHARE_MEMORY_METASPACESHARED_HPP