1/*
2 * Copyright (c) 1997, 2017, 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 OS_WINDOWS_VM_OS_WINDOWS_HPP
26#define OS_WINDOWS_VM_OS_WINDOWS_HPP
27// Win32_OS defines the interface to windows operating systems
28
29// Information about the protection of the page at address '0' on this os.
30static bool zero_page_read_protected() { return true; }
31
32// File conventions
33static const char* file_separator() { return "\\"; }
34static const char* line_separator() { return "\r\n"; }
35static const char* path_separator() { return ";"; }
36
37class win32 {
38  friend class os;
39  friend unsigned __stdcall thread_native_entry(class Thread*);
40
41 protected:
42  static int    _vm_page_size;
43  static int    _vm_allocation_granularity;
44  static int    _processor_type;
45  static int    _processor_level;
46  static julong _physical_memory;
47  static size_t _default_stack_size;
48  static bool   _is_windows_server;
49  static bool   _has_exit_bug;
50
51  static void print_windows_version(outputStream* st);
52
53 public:
54  // Windows-specific interface:
55  static void   initialize_system_info();
56  static void   setmode_streams();
57
58  // Processor info as provided by NT
59  static int processor_type()  { return _processor_type;  }
60  static int processor_level() {
61    return _processor_level;
62  }
63  static julong available_memory();
64  static julong physical_memory() { return _physical_memory; }
65
66  // load dll from Windows system directory or Windows directory
67  static HINSTANCE load_Windows_dll(const char* name, char *ebuf, int ebuflen);
68
69 private:
70  enum Ept { EPT_THREAD, EPT_PROCESS, EPT_PROCESS_DIE };
71  // Wrapper around _endthreadex(), exit() and _exit()
72  static int exit_process_or_thread(Ept what, int exit_code);
73
74  static void initialize_performance_counter();
75
76 public:
77  // Generic interface:
78
79  // Trace number of created threads
80  static          intx  _os_thread_limit;
81  static volatile intx  _os_thread_count;
82
83  // Tells whether this is a server version of Windows
84  static bool is_windows_server() { return _is_windows_server; }
85
86  // Tells whether there can be the race bug during process exit on this platform
87  static bool has_exit_bug() { return _has_exit_bug; }
88
89  // Returns the byte size of a virtual memory page
90  static int vm_page_size() { return _vm_page_size; }
91
92  // Returns the size in bytes of memory blocks which can be allocated.
93  static int vm_allocation_granularity() { return _vm_allocation_granularity; }
94
95  // Read the headers for the executable that started the current process into
96  // the structure passed in (see winnt.h).
97  static void read_executable_headers(PIMAGE_NT_HEADERS);
98
99  // Default stack size for the current process.
100  static size_t default_stack_size() { return _default_stack_size; }
101
102  static bool get_frame_at_stack_banging_point(JavaThread* thread,
103                          struct _EXCEPTION_POINTERS* exceptionInfo,
104                          address pc, frame* fr);
105
106#ifndef _WIN64
107  // A wrapper to install a structured exception handler for fast JNI accesors.
108  static address fast_jni_accessor_wrapper(BasicType);
109#endif
110
111  // filter function to ignore faults on serializations page
112  static LONG WINAPI serialize_fault_filter(struct _EXCEPTION_POINTERS* e);
113
114  // Fast access to current thread
115protected:
116  static int _thread_ptr_offset;
117private:
118  static void initialize_thread_ptr_offset();
119public:
120  static inline void set_thread_ptr_offset(int offset) {
121    _thread_ptr_offset = offset;
122  }
123  static inline int get_thread_ptr_offset() { return _thread_ptr_offset; }
124};
125
126static void write_memory_serialize_page_with_handler(JavaThread* thread) {
127  // Due to chained nature of SEH handlers we have to be sure
128  // that our handler is always last handler before an attempt to write
129  // into serialization page - it can fault if we access this page
130  // right in the middle of protect/unprotect sequence by remote
131  // membar logic.
132  // __try/__except are very lightweight operations (only several
133  // instructions not affecting control flow directly on x86)
134  // so we can use it here, on very time critical path
135  __try {
136    write_memory_serialize_page(thread);
137  } __except (win32::serialize_fault_filter((_EXCEPTION_POINTERS*)_exception_info()))
138    {}
139}
140
141/*
142 * Crash protection for the watcher thread. Wrap the callback
143 * with a __try { call() }
144 * To be able to use this - don't take locks, don't rely on destructors,
145 * don't make OS library calls, don't allocate memory, don't print,
146 * don't call code that could leave the heap / memory in an inconsistent state,
147 * or anything else where we are not in control if we suddenly jump out.
148 */
149class ThreadCrashProtection : public StackObj {
150public:
151  static bool is_crash_protected(Thread* thr) {
152    return _crash_protection != NULL && _protected_thread == thr;
153  }
154
155  ThreadCrashProtection();
156  bool call(os::CrashProtectionCallback& cb);
157private:
158  static Thread* _protected_thread;
159  static ThreadCrashProtection* _crash_protection;
160  static volatile intptr_t _crash_mux;
161};
162
163class PlatformEvent : public CHeapObj<mtInternal> {
164  private:
165    double CachePad [4] ;   // increase odds that _Event is sole occupant of cache line
166    volatile int _Event ;
167    HANDLE _ParkHandle ;
168
169  public:       // TODO-FIXME: make dtor private
170    ~PlatformEvent() { guarantee (0, "invariant") ; }
171
172  public:
173    PlatformEvent() {
174      _Event   = 0 ;
175      _ParkHandle = CreateEvent (NULL, false, false, NULL) ;
176      guarantee (_ParkHandle != NULL, "invariant") ;
177    }
178
179    // Exercise caution using reset() and fired() - they may require MEMBARs
180    void reset() { _Event = 0 ; }
181    int  fired() { return _Event; }
182    void park () ;
183    void unpark () ;
184    int  park (jlong millis) ;
185} ;
186
187
188
189class PlatformParker : public CHeapObj<mtInternal> {
190  protected:
191    HANDLE _ParkEvent ;
192
193  public:
194    ~PlatformParker () { guarantee (0, "invariant") ; }
195    PlatformParker  () {
196      _ParkEvent = CreateEvent (NULL, true, false, NULL) ;
197      guarantee (_ParkEvent != NULL, "invariant") ;
198    }
199
200} ;
201
202#endif // OS_WINDOWS_VM_OS_WINDOWS_HPP
203