1 /*
2 * Copyright (c) 2003, 2015, 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 "mutex_bsd.inline.hpp"
42 #include "nativeInst_zero.hpp"
43 #include "os_share_bsd.hpp"
44 #include "prims/jniFastGetField.hpp"
45 #include "prims/jvm.h"
46 #include "prims/jvm_misc.hpp"
47 #include "runtime/arguments.hpp"
48 #include "runtime/extendedPC.hpp"
49 #include "runtime/frame.inline.hpp"
50 #include "runtime/interfaceSupport.hpp"
51 #include "runtime/java.hpp"
52 #include "runtime/javaCalls.hpp"
53 #include "runtime/mutexLocker.hpp"
54 #include "runtime/osThread.hpp"
55 #include "runtime/sharedRuntime.hpp"
56 #include "runtime/stubRoutines.hpp"
57 #include "runtime/thread.inline.hpp"
58 #include "runtime/timer.hpp"
59 #include "utilities/events.hpp"
60 #include "utilities/vmError.hpp"
61
62 // See stubGenerator_zero.cpp
63 #include <setjmp.h>
64 extern sigjmp_buf* get_jmp_buf_for_continuation();
65
66 address os::current_stack_pointer() {
67 address dummy = (address) &dummy;
68 return dummy;
69 }
70
71 frame os::get_sender_for_C_frame(frame* fr) {
72 ShouldNotCallThis();
73 return frame();
74 }
75
76 frame os::current_frame() {
77 // The only thing that calls this is the stack printing code in
78 // VMError::report:
79 // - Step 110 (printing stack bounds) uses the sp in the frame
80 // to determine the amount of free space on the stack. We
81 // set the sp to a close approximation of the real value in
82 // order to allow this step to complete.
83 // - Step 120 (printing native stack) tries to walk the stack.
84 // The frame we create has a NULL pc, which is ignored as an
85 // invalid frame.
86 frame dummy = frame();
87 dummy.set_sp((intptr_t *) current_stack_pointer());
88 return dummy;
89 }
90
91 char* os::non_memory_address_word() {
92 // Must never look like an address returned by reserve_memory,
93 // even in its subfields (as defined by the CPU immediate fields,
94 // if the CPU splits constants across multiple instructions).
95 #ifdef SPARC
96 // On SPARC, 0 != %hi(any real address), because there is no
97 // allocation in the first 1Kb of the virtual address space.
98 return (char *) 0;
99 #else
100 // This is the value for x86; works pretty well for PPC too.
101 return (char *) -1;
102 #endif // SPARC
103 }
104
105 void os::initialize_thread(Thread* thr) {
106 // Nothing to do.
107 }
108
109 address os::Bsd::ucontext_get_pc(ucontext_t* uc) {
110 ShouldNotCallThis();
111 return NULL;
112 }
113
114 void os::Bsd::ucontext_set_pc(ucontext_t * uc, address pc) {
115 ShouldNotCallThis();
116 }
117
118 ExtendedPC os::fetch_frame_from_context(void* ucVoid,
119 intptr_t** ret_sp,
120 intptr_t** ret_fp) {
121 ShouldNotCallThis();
122 return ExtendedPC();
123 }
124
125 frame os::fetch_frame_from_context(void* ucVoid) {
126 ShouldNotCallThis();
127 return frame();
128 }
129
130 extern "C" JNIEXPORT int
131 JVM_handle_bsd_signal(int sig,
132 siginfo_t* info,
133 void* ucVoid,
134 int abort_if_unrecognized) {
135 ucontext_t* uc = (ucontext_t*) ucVoid;
136
137 Thread* t = Thread::current_or_null_safe();
138
139 SignalHandlerMark shm(t);
140
141 // handle SafeFetch faults
142 if (sig == SIGSEGV || sig == SIGBUS) {
143 sigjmp_buf* const pjb = get_jmp_buf_for_continuation();
144 if (pjb) {
145 siglongjmp(*pjb, 1);
146 }
147 }
148
149 // Note: it's not uncommon that JNI code uses signal/sigset to
150 // install then restore certain signal handler (e.g. to temporarily
151 // block SIGPIPE, or have a SIGILL handler when detecting CPU
152 // type). When that happens, JVM_handle_bsd_signal() might be
153 // invoked with junk info/ucVoid. To avoid unnecessary crash when
154 // libjsig is not preloaded, try handle signals that do not require
155 // siginfo/ucontext first.
156
157 if (sig == SIGPIPE || sig == SIGXFSZ) {
158 // allow chained handler to go first
159 if (os::Bsd::chained_handler(sig, info, ucVoid)) {
160 return true;
161 } else {
162 if (PrintMiscellaneous && (WizardMode || Verbose)) {
163 char buf[64];
164 warning("Ignoring %s - see bugs 4229104 or 646499219",
165 os::exception_name(sig, buf, sizeof(buf)));
166 }
167 return true;
168 }
169 }
170
171 JavaThread* thread = NULL;
172 VMThread* vmthread = NULL;
173 if (os::Bsd::signal_handlers_are_installed) {
174 if (t != NULL ){
175 if(t->is_Java_thread()) {
176 thread = (JavaThread*)t;
177 }
178 else if(t->is_VM_thread()){
179 vmthread = (VMThread *)t;
180 }
181 }
182 }
183
184 if (info != NULL && thread != NULL) {
185 // Handle ALL stack overflow variations here
186 if (sig == SIGSEGV || sig == SIGBUS) {
187 address addr = (address) info->si_addr;
188
189 // check if fault address is within thread stack
190 if (addr < thread->stack_base() &&
191 addr >= thread->stack_base() - thread->stack_size()) {
192 // stack overflow
193 if (thread->in_stack_yellow_zone(addr)) {
194 thread->disable_stack_yellow_zone();
195 ShouldNotCallThis();
196 }
197 else if (thread->in_stack_red_zone(addr)) {
198 thread->disable_stack_red_zone();
199 ShouldNotCallThis();
200 }
201 }
202 }
203
204 /*if (thread->thread_state() == _thread_in_Java) {
205 ShouldNotCallThis();
206 }
207 else*/ if (thread->thread_state() == _thread_in_vm &&
208 sig == SIGBUS && thread->doing_unsafe_access()) {
209 ShouldNotCallThis();
210 }
211
212 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC
213 // kicks in and the heap gets shrunk before the field access.
214 /*if (sig == SIGSEGV || sig == SIGBUS) {
215 address addr = JNI_FastGetField::find_slowcase_pc(pc);
216 if (addr != (address)-1) {
217 stub = addr;
218 }
219 }*/
220
221 // Check to see if we caught the safepoint code in the process
222 // of write protecting the memory serialization page. It write
223 // enables the page immediately after protecting it so we can
224 // just return to retry the write.
225 if ((sig == SIGSEGV || sig == SIGBUS) &&
226 os::is_memory_serialize_page(thread, (address) info->si_addr)) {
227 // Block current thread until permission is restored.
228 os::block_on_serialize_page_trap();
229 return true;
230 }
231 }
232
233 // signal-chaining
234 if (os::Bsd::chained_handler(sig, info, ucVoid)) {
235 return true;
236 }
237
238 if (!abort_if_unrecognized) {
239 // caller wants another chance, so give it to him
240 return false;
241 }
242
243 #ifndef PRODUCT
244 if (sig == SIGSEGV) {
245 fatal("\n#"
246 "\n# /--------------------\\"
247 "\n# | segmentation fault |"
248 "\n# \\---\\ /--------------/"
249 "\n# /"
250 "\n# [-] |\\_/| "
251 "\n# (+)=C |o o|__ "
252 "\n# | | =-*-=__\\ "
253 "\n# OOO c_c_(___)");
254 }
255 #endif // !PRODUCT
256
257 const char *fmt =
258 "caught unhandled signal " INT32_FORMAT " at address " PTR_FORMAT;
259 char buf[128];
260
261 sprintf(buf, fmt, sig, info->si_addr);
262 fatal(buf);
263 return false;
264 }
265
266 void os::Bsd::init_thread_fpu_state(void) {
267 // Nothing to do
268 }
269
270 bool os::is_allocatable(size_t bytes) {
271 #ifdef _LP64
272 return true;
273 #else
274 if (bytes < 2 * G) {
275 return true;
276 }
277
278 char* addr = reserve_memory(bytes, NULL);
279
280 if (addr != NULL) {
281 release_memory(addr, bytes);
282 }
283
284 return addr != NULL;
285 #endif // _LP64
286 }
287
288 ///////////////////////////////////////////////////////////////////////////////
289 // thread stack
290
291 size_t os::Bsd::min_stack_allowed = 64 * K;
292
293 size_t os::Bsd::default_stack_size(os::ThreadType thr_type) {
294 #ifdef _LP64
295 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
296 #else
297 size_t s = (thr_type == os::compiler_thread ? 2 * M : 512 * K);
298 #endif // _LP64
299 return s;
300 }
301
302 size_t os::Bsd::default_guard_size(os::ThreadType thr_type) {
303 // Only enable glibc guard pages for non-Java threads
304 // (Java threads have HotSpot guard pages)
305 return (thr_type == java_thread ? 0 : page_size());
306 }
307
308 static void current_stack_region(address *bottom, size_t *size) {
309 address stack_bottom;
310 address stack_top;
311 size_t stack_bytes;
312
313 #ifdef __APPLE__
314 pthread_t self = pthread_self();
315 stack_top = (address) pthread_get_stackaddr_np(self);
316 stack_bytes = pthread_get_stacksize_np(self);
317 stack_bottom = stack_top - stack_bytes;
318 #elif defined(__OpenBSD__)
319 stack_t ss;
320 int rslt = pthread_stackseg_np(pthread_self(), &ss);
321
322 if (rslt != 0)
323 fatal("pthread_stackseg_np failed with err = " INT32_FORMAT, rslt);
324
325 stack_top = (address) ss.ss_sp;
326 stack_bytes = ss.ss_size;
327 stack_bottom = stack_top - stack_bytes;
328 #else
329 pthread_attr_t attr;
330
331 int rslt = pthread_attr_init(&attr);
332
333 // JVM needs to know exact stack location, abort if it fails
334 if (rslt != 0)
335 fatal("pthread_attr_init failed with err = " INT32_FORMAT, rslt);
336
337 rslt = pthread_attr_get_np(pthread_self(), &attr);
338
339 if (rslt != 0)
340 fatal("pthread_attr_get_np failed with err = " INT32_FORMAT, rslt);
341
342 if (pthread_attr_getstackaddr(&attr, (void **) &stack_bottom) != 0 ||
343 pthread_attr_getstacksize(&attr, &stack_bytes) != 0) {
344 fatal("Can not locate current stack attributes!");
345 }
346
347 pthread_attr_destroy(&attr);
348
349 stack_top = stack_bottom + stack_bytes;
350 #endif
351
352 assert(os::current_stack_pointer() >= stack_bottom, "should do");
353 assert(os::current_stack_pointer() < stack_top, "should do");
354
355 *bottom = stack_bottom;
356 *size = stack_top - stack_bottom;
357 }
358
359 address os::current_stack_base() {
360 address bottom;
361 size_t size;
362 current_stack_region(&bottom, &size);
363 return bottom + size;
364 }
365
366 size_t os::current_stack_size() {
367 // stack size includes normal stack and HotSpot guard pages
368 address bottom;
369 size_t size;
370 current_stack_region(&bottom, &size);
371 return size;
372 }
373
374 /////////////////////////////////////////////////////////////////////////////
375 // helper functions for fatal error handler
376
377 void os::print_context(outputStream* st, void* context) {
378 ShouldNotCallThis();
379 }
380
381 void os::print_register_info(outputStream *st, void *context) {
382 ShouldNotCallThis();
383 }
384
385 /////////////////////////////////////////////////////////////////////////////
386 // Stubs for things that would be in bsd_zero.s if it existed.
387 // You probably want to disassemble these monkeys to check they're ok.
388
389 extern "C" {
390 int SpinPause() {
391 return 1;
392 }
393
394 void _Copy_conjoint_jshorts_atomic(jshort* from, jshort* to, size_t count) {
395 if (from > to) {
396 jshort *end = from + count;
397 while (from < end)
398 *(to++) = *(from++);
399 }
400 else if (from < to) {
401 jshort *end = from;
402 from += count - 1;
403 to += count - 1;
404 while (from >= end)
405 *(to--) = *(from--);
406 }
407 }
408 void _Copy_conjoint_jints_atomic(jint* from, jint* to, size_t count) {
409 if (from > to) {
410 jint *end = from + count;
411 while (from < end)
412 *(to++) = *(from++);
413 }
414 else if (from < to) {
415 jint *end = from;
416 from += count - 1;
417 to += count - 1;
418 while (from >= end)
419 *(to--) = *(from--);
420 }
421 }
422 void _Copy_conjoint_jlongs_atomic(jlong* from, jlong* to, size_t count) {
423 if (from > to) {
424 jlong *end = from + count;
425 while (from < end)
426 os::atomic_copy64(from++, to++);
427 }
428 else if (from < to) {
429 jlong *end = from;
430 from += count - 1;
431 to += count - 1;
432 while (from >= end)
433 os::atomic_copy64(from--, to--);
434 }
435 }
436
437 void _Copy_arrayof_conjoint_bytes(HeapWord* from,
438 HeapWord* to,
439 size_t count) {
440 memmove(to, from, count);
441 }
442 void _Copy_arrayof_conjoint_jshorts(HeapWord* from,
443 HeapWord* to,
444 size_t count) {
445 memmove(to, from, count * 2);
446 }
447 void _Copy_arrayof_conjoint_jints(HeapWord* from,
448 HeapWord* to,
449 size_t count) {
450 memmove(to, from, count * 4);
451 }
452 void _Copy_arrayof_conjoint_jlongs(HeapWord* from,
453 HeapWord* to,
454 size_t count) {
455 memmove(to, from, count * 8);
456 }
457 };
458
459 /////////////////////////////////////////////////////////////////////////////
460 // Implementations of atomic operations not supported by processors.
461 // -- http://gcc.gnu.org/onlinedocs/gcc-4.2.1/gcc/Atomic-Builtins.html
462
463 #ifndef _LP64
464 extern "C" {
465 long long unsigned int __sync_val_compare_and_swap_8(
466 volatile void *ptr,
467 long long unsigned int oldval,
468 long long unsigned int newval) {
469 ShouldNotCallThis();
470 }
471 };
472 #endif // !_LP64
473
474 #ifndef PRODUCT
475 void os::verify_stack_alignment() {
476 }
477 #endif
478
479 int os::extra_bang_size_in_bytes() {
480 // Zero does not require an additional stack bang.
481 return 0;
482 }