1/*
2 * Copyright (c) 2003, 2016, Oracle and/or its affiliates. All rights reserved.
3 * Copyright 2007, 2008, 2009, 2010 Red Hat, Inc.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26#if !defined(__APPLE__) && !defined(__NetBSD__)
27#include <pthread.h>
28# include <pthread_np.h> /* For pthread_attr_get_np */
29#endif
30
31// no precompiled headers
32#include "assembler_zero.inline.hpp"
33#include "classfile/classLoader.hpp"
34#include "classfile/systemDictionary.hpp"
35#include "classfile/vmSymbols.hpp"
36#include "code/icBuffer.hpp"
37#include "code/vtableStubs.hpp"
38#include "interpreter/interpreter.hpp"
39#include "jvm_bsd.h"
40#include "memory/allocation.inline.hpp"
41#include "nativeInst_zero.hpp"
42#include "os_share_bsd.hpp"
43#include "prims/jniFastGetField.hpp"
44#include "prims/jvm.h"
45#include "prims/jvm_misc.hpp"
46#include "runtime/arguments.hpp"
47#include "runtime/extendedPC.hpp"
48#include "runtime/frame.inline.hpp"
49#include "runtime/interfaceSupport.hpp"
50#include "runtime/java.hpp"
51#include "runtime/javaCalls.hpp"
52#include "runtime/mutexLocker.hpp"
53#include "runtime/osThread.hpp"
54#include "runtime/sharedRuntime.hpp"
55#include "runtime/stubRoutines.hpp"
56#include "runtime/thread.inline.hpp"
57#include "runtime/timer.hpp"
58#include "utilities/events.hpp"
59#include "utilities/vmError.hpp"
60
61// See stubGenerator_zero.cpp
62#include <setjmp.h>
63extern sigjmp_buf* get_jmp_buf_for_continuation();
64
65address os::current_stack_pointer() {
66  address dummy = (address) &dummy;
67  return dummy;
68}
69
70frame os::get_sender_for_C_frame(frame* fr) {
71  ShouldNotCallThis();
72  return frame();
73}
74
75frame os::current_frame() {
76  // The only thing that calls this is the stack printing code in
77  // VMError::report:
78  //   - Step 110 (printing stack bounds) uses the sp in the frame
79  //     to determine the amount of free space on the stack.  We
80  //     set the sp to a close approximation of the real value in
81  //     order to allow this step to complete.
82  //   - Step 120 (printing native stack) tries to walk the stack.
83  //     The frame we create has a NULL pc, which is ignored as an
84  //     invalid frame.
85  frame dummy = frame();
86  dummy.set_sp((intptr_t *) current_stack_pointer());
87  return dummy;
88}
89
90char* os::non_memory_address_word() {
91  // Must never look like an address returned by reserve_memory,
92  // even in its subfields (as defined by the CPU immediate fields,
93  // if the CPU splits constants across multiple instructions).
94#ifdef SPARC
95  // On SPARC, 0 != %hi(any real address), because there is no
96  // allocation in the first 1Kb of the virtual address space.
97  return (char *) 0;
98#else
99  // This is the value for x86; works pretty well for PPC too.
100  return (char *) -1;
101#endif // SPARC
102}
103
104void os::initialize_thread(Thread* thr) {
105  // Nothing to do.
106}
107
108address os::Bsd::ucontext_get_pc(const ucontext_t* uc) {
109  ShouldNotCallThis();
110  return NULL;
111}
112
113void os::Bsd::ucontext_set_pc(ucontext_t * uc, address pc) {
114  ShouldNotCallThis();
115}
116
117ExtendedPC os::fetch_frame_from_context(const void* ucVoid,
118                                        intptr_t** ret_sp,
119                                        intptr_t** ret_fp) {
120  ShouldNotCallThis();
121  return ExtendedPC();
122}
123
124frame os::fetch_frame_from_context(const void* ucVoid) {
125  ShouldNotCallThis();
126  return frame();
127}
128
129extern "C" JNIEXPORT int
130JVM_handle_bsd_signal(int sig,
131                        siginfo_t* info,
132                        void* ucVoid,
133                        int abort_if_unrecognized) {
134  ucontext_t* uc = (ucontext_t*) ucVoid;
135
136  Thread* t = Thread::current_or_null_safe();
137
138  SignalHandlerMark shm(t);
139
140  // handle SafeFetch faults
141  if (sig == SIGSEGV || sig == SIGBUS) {
142    sigjmp_buf* const pjb = get_jmp_buf_for_continuation();
143    if (pjb) {
144      siglongjmp(*pjb, 1);
145    }
146  }
147
148  // Note: it's not uncommon that JNI code uses signal/sigset to
149  // install then restore certain signal handler (e.g. to temporarily
150  // block SIGPIPE, or have a SIGILL handler when detecting CPU
151  // type). When that happens, JVM_handle_bsd_signal() might be
152  // invoked with junk info/ucVoid. To avoid unnecessary crash when
153  // libjsig is not preloaded, try handle signals that do not require
154  // siginfo/ucontext first.
155
156  if (sig == SIGPIPE || sig == SIGXFSZ) {
157    // allow chained handler to go first
158    if (os::Bsd::chained_handler(sig, info, ucVoid)) {
159      return true;
160    } else {
161      // Ignoring SIGPIPE/SIGXFSZ - see bugs 4229104 or 6499219
162      return true;
163    }
164  }
165
166  JavaThread* thread = NULL;
167  VMThread* vmthread = NULL;
168  if (os::Bsd::signal_handlers_are_installed) {
169    if (t != NULL ){
170      if(t->is_Java_thread()) {
171        thread = (JavaThread*)t;
172      }
173      else if(t->is_VM_thread()){
174        vmthread = (VMThread *)t;
175      }
176    }
177  }
178
179  if (info != NULL && thread != NULL) {
180    // Handle ALL stack overflow variations here
181    if (sig == SIGSEGV || sig == SIGBUS) {
182      address addr = (address) info->si_addr;
183
184      // check if fault address is within thread stack
185      if (thread->on_local_stack(addr)) {
186        // stack overflow
187        if (thread->in_stack_yellow_reserved_zone(addr)) {
188          thread->disable_stack_yellow_reserved_zone();
189          ShouldNotCallThis();
190        }
191        else if (thread->in_stack_red_zone(addr)) {
192          thread->disable_stack_red_zone();
193          ShouldNotCallThis();
194        }
195      }
196    }
197
198    /*if (thread->thread_state() == _thread_in_Java) {
199      ShouldNotCallThis();
200    }
201    else*/ if (thread->thread_state() == _thread_in_vm &&
202               sig == SIGBUS && thread->doing_unsafe_access()) {
203      ShouldNotCallThis();
204    }
205
206    // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC
207    // kicks in and the heap gets shrunk before the field access.
208    /*if (sig == SIGSEGV || sig == SIGBUS) {
209      address addr = JNI_FastGetField::find_slowcase_pc(pc);
210      if (addr != (address)-1) {
211        stub = addr;
212      }
213    }*/
214
215    // Check to see if we caught the safepoint code in the process
216    // of write protecting the memory serialization page.  It write
217    // enables the page immediately after protecting it so we can
218    // just return to retry the write.
219    if ((sig == SIGSEGV || sig == SIGBUS) &&
220        os::is_memory_serialize_page(thread, (address) info->si_addr)) {
221      // Block current thread until permission is restored.
222      os::block_on_serialize_page_trap();
223      return true;
224    }
225  }
226
227  // signal-chaining
228  if (os::Bsd::chained_handler(sig, info, ucVoid)) {
229     return true;
230  }
231
232  if (!abort_if_unrecognized) {
233    // caller wants another chance, so give it to him
234    return false;
235  }
236
237#ifndef PRODUCT
238  if (sig == SIGSEGV) {
239    fatal("\n#"
240          "\n#    /--------------------\\"
241          "\n#    | segmentation fault |"
242          "\n#    \\---\\ /--------------/"
243          "\n#        /"
244          "\n#    [-]        |\\_/|    "
245          "\n#    (+)=C      |o o|__  "
246          "\n#    | |        =-*-=__\\ "
247          "\n#    OOO        c_c_(___)");
248  }
249#endif // !PRODUCT
250
251  const char *fmt =
252      "caught unhandled signal " INT32_FORMAT " at address " PTR_FORMAT;
253  char buf[128];
254
255  sprintf(buf, fmt, sig, info->si_addr);
256  fatal(buf);
257  return false;
258}
259
260void os::Bsd::init_thread_fpu_state(void) {
261  // Nothing to do
262}
263
264bool os::is_allocatable(size_t bytes) {
265#ifdef _LP64
266  return true;
267#else
268  if (bytes < 2 * G) {
269    return true;
270  }
271
272  char* addr = reserve_memory(bytes, NULL);
273
274  if (addr != NULL) {
275    release_memory(addr, bytes);
276  }
277
278  return addr != NULL;
279#endif // _LP64
280}
281
282///////////////////////////////////////////////////////////////////////////////
283// thread stack
284
285size_t os::Posix::_compiler_thread_min_stack_allowed = 64 * K;
286size_t os::Posix::_java_thread_min_stack_allowed = 64 * K;
287size_t os::Posix::_vm_internal_thread_min_stack_allowed = 64 * K;
288
289size_t os::Posix::default_stack_size(os::ThreadType thr_type) {
290#ifdef _LP64
291  size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
292#else
293  size_t s = (thr_type == os::compiler_thread ? 2 * M : 512 * K);
294#endif // _LP64
295  return s;
296}
297
298static void current_stack_region(address *bottom, size_t *size) {
299  address stack_bottom;
300  address stack_top;
301  size_t stack_bytes;
302
303#ifdef __APPLE__
304  pthread_t self = pthread_self();
305  stack_top = (address) pthread_get_stackaddr_np(self);
306  stack_bytes = pthread_get_stacksize_np(self);
307  stack_bottom = stack_top - stack_bytes;
308#elif defined(__OpenBSD__)
309  stack_t ss;
310  int rslt = pthread_stackseg_np(pthread_self(), &ss);
311
312  if (rslt != 0)
313    fatal("pthread_stackseg_np failed with error = " INT32_FORMAT, rslt);
314
315  stack_top = (address) ss.ss_sp;
316  stack_bytes  = ss.ss_size;
317  stack_bottom = stack_top - stack_bytes;
318#else
319  pthread_attr_t attr;
320
321  int rslt = pthread_attr_init(&attr);
322
323  // JVM needs to know exact stack location, abort if it fails
324  if (rslt != 0)
325    fatal("pthread_attr_init failed with error = " INT32_FORMAT, rslt);
326
327  rslt = pthread_attr_get_np(pthread_self(), &attr);
328
329  if (rslt != 0)
330    fatal("pthread_attr_get_np failed with error = " INT32_FORMAT, rslt);
331
332  if (pthread_attr_getstackaddr(&attr, (void **) &stack_bottom) != 0 ||
333      pthread_attr_getstacksize(&attr, &stack_bytes) != 0) {
334    fatal("Can not locate current stack attributes!");
335  }
336
337  pthread_attr_destroy(&attr);
338
339  stack_top = stack_bottom + stack_bytes;
340#endif
341
342  assert(os::current_stack_pointer() >= stack_bottom, "should do");
343  assert(os::current_stack_pointer() < stack_top, "should do");
344
345  *bottom = stack_bottom;
346  *size = stack_top - stack_bottom;
347}
348
349address os::current_stack_base() {
350  address bottom;
351  size_t size;
352  current_stack_region(&bottom, &size);
353  return bottom + size;
354}
355
356size_t os::current_stack_size() {
357  // stack size includes normal stack and HotSpot guard pages
358  address bottom;
359  size_t size;
360  current_stack_region(&bottom, &size);
361  return size;
362}
363
364/////////////////////////////////////////////////////////////////////////////
365// helper functions for fatal error handler
366
367void os::print_context(outputStream* st, const void* context) {
368  ShouldNotCallThis();
369}
370
371void os::print_register_info(outputStream *st, const void *context) {
372  ShouldNotCallThis();
373}
374
375/////////////////////////////////////////////////////////////////////////////
376// Stubs for things that would be in bsd_zero.s if it existed.
377// You probably want to disassemble these monkeys to check they're ok.
378
379extern "C" {
380  int SpinPause() {
381    return 1;
382  }
383
384  void _Copy_conjoint_jshorts_atomic(jshort* from, jshort* to, size_t count) {
385    if (from > to) {
386      jshort *end = from + count;
387      while (from < end)
388        *(to++) = *(from++);
389    }
390    else if (from < to) {
391      jshort *end = from;
392      from += count - 1;
393      to   += count - 1;
394      while (from >= end)
395        *(to--) = *(from--);
396    }
397  }
398  void _Copy_conjoint_jints_atomic(jint* from, jint* to, size_t count) {
399    if (from > to) {
400      jint *end = from + count;
401      while (from < end)
402        *(to++) = *(from++);
403    }
404    else if (from < to) {
405      jint *end = from;
406      from += count - 1;
407      to   += count - 1;
408      while (from >= end)
409        *(to--) = *(from--);
410    }
411  }
412  void _Copy_conjoint_jlongs_atomic(jlong* from, jlong* to, size_t count) {
413    if (from > to) {
414      jlong *end = from + count;
415      while (from < end)
416        os::atomic_copy64(from++, to++);
417    }
418    else if (from < to) {
419      jlong *end = from;
420      from += count - 1;
421      to   += count - 1;
422      while (from >= end)
423        os::atomic_copy64(from--, to--);
424    }
425  }
426
427  void _Copy_arrayof_conjoint_bytes(HeapWord* from,
428                                    HeapWord* to,
429                                    size_t    count) {
430    memmove(to, from, count);
431  }
432  void _Copy_arrayof_conjoint_jshorts(HeapWord* from,
433                                      HeapWord* to,
434                                      size_t    count) {
435    memmove(to, from, count * 2);
436  }
437  void _Copy_arrayof_conjoint_jints(HeapWord* from,
438                                    HeapWord* to,
439                                    size_t    count) {
440    memmove(to, from, count * 4);
441  }
442  void _Copy_arrayof_conjoint_jlongs(HeapWord* from,
443                                     HeapWord* to,
444                                     size_t    count) {
445    memmove(to, from, count * 8);
446  }
447};
448
449/////////////////////////////////////////////////////////////////////////////
450// Implementations of atomic operations not supported by processors.
451//  -- http://gcc.gnu.org/onlinedocs/gcc-4.2.1/gcc/Atomic-Builtins.html
452
453#ifndef _LP64
454extern "C" {
455  long long unsigned int __sync_val_compare_and_swap_8(
456    volatile void *ptr,
457    long long unsigned int oldval,
458    long long unsigned int newval) {
459    ShouldNotCallThis();
460  }
461};
462#endif // !_LP64
463
464#ifndef PRODUCT
465void os::verify_stack_alignment() {
466}
467#endif
468
469int os::extra_bang_size_in_bytes() {
470  // Zero does not require an additional stack bang.
471  return 0;
472}
473