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>
63 extern sigjmp_buf* get_jmp_buf_for_continuation();
64
65 address os::current_stack_pointer() {
66 address dummy = (address) &dummy;
67 return dummy;
68 }
69
70 frame os::get_sender_for_C_frame(frame* fr) {
71 ShouldNotCallThis();
72 return frame();
73 }
74
75 frame 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
90 char* 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
104 void os::initialize_thread(Thread* thr) {
105 // Nothing to do.
106 }
107
108 address os::Bsd::ucontext_get_pc(const ucontext_t* uc) {
109 ShouldNotCallThis();
110 return NULL;
111 }
112
113 void os::Bsd::ucontext_set_pc(ucontext_t * uc, address pc) {
114 ShouldNotCallThis();
115 }
116
117 ExtendedPC 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
124 frame os::fetch_frame_from_context(const void* ucVoid) {
125 ShouldNotCallThis();
126 return frame();
127 }
128
129 extern "C" JNIEXPORT int
130 JVM_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
260 void os::Bsd::init_thread_fpu_state(void) {
261 // Nothing to do
262 }
263
264 bool 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
285 size_t os::Bsd::min_stack_allowed = 64 * K;
286
287 size_t os::Bsd::default_stack_size(os::ThreadType thr_type) {
288 #ifdef _LP64
289 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
290 #else
291 size_t s = (thr_type == os::compiler_thread ? 2 * M : 512 * K);
292 #endif // _LP64
293 return s;
294 }
295
296 size_t os::Bsd::default_guard_size(os::ThreadType thr_type) {
297 // Only enable glibc guard pages for non-Java threads
298 // (Java threads have HotSpot guard pages)
299 return (thr_type == java_thread ? 0 : page_size());
300 }
301
302 static void current_stack_region(address *bottom, size_t *size) {
303 address stack_bottom;
304 address stack_top;
305 size_t stack_bytes;
306
307 #ifdef __APPLE__
308 pthread_t self = pthread_self();
309 stack_top = (address) pthread_get_stackaddr_np(self);
310 stack_bytes = pthread_get_stacksize_np(self);
311 stack_bottom = stack_top - stack_bytes;
312 #elif defined(__OpenBSD__)
313 stack_t ss;
314 int rslt = pthread_stackseg_np(pthread_self(), &ss);
315
316 if (rslt != 0)
317 fatal("pthread_stackseg_np failed with err = " INT32_FORMAT, rslt);
318
319 stack_top = (address) ss.ss_sp;
320 stack_bytes = ss.ss_size;
321 stack_bottom = stack_top - stack_bytes;
322 #else
323 pthread_attr_t attr;
324
325 int rslt = pthread_attr_init(&attr);
326
327 // JVM needs to know exact stack location, abort if it fails
328 if (rslt != 0)
329 fatal("pthread_attr_init failed with err = " INT32_FORMAT, rslt);
330
331 rslt = pthread_attr_get_np(pthread_self(), &attr);
332
333 if (rslt != 0)
334 fatal("pthread_attr_get_np failed with err = " INT32_FORMAT, rslt);
335
336 if (pthread_attr_getstackaddr(&attr, (void **) &stack_bottom) != 0 ||
337 pthread_attr_getstacksize(&attr, &stack_bytes) != 0) {
338 fatal("Can not locate current stack attributes!");
339 }
340
341 pthread_attr_destroy(&attr);
342
343 stack_top = stack_bottom + stack_bytes;
344 #endif
345
346 assert(os::current_stack_pointer() >= stack_bottom, "should do");
347 assert(os::current_stack_pointer() < stack_top, "should do");
348
349 *bottom = stack_bottom;
350 *size = stack_top - stack_bottom;
351 }
352
353 address os::current_stack_base() {
354 address bottom;
355 size_t size;
356 current_stack_region(&bottom, &size);
357 return bottom + size;
358 }
359
360 size_t os::current_stack_size() {
361 // stack size includes normal stack and HotSpot guard pages
362 address bottom;
363 size_t size;
364 current_stack_region(&bottom, &size);
365 return size;
366 }
367
368 /////////////////////////////////////////////////////////////////////////////
369 // helper functions for fatal error handler
370
371 void os::print_context(outputStream* st, const void* context) {
372 ShouldNotCallThis();
373 }
374
375 void os::print_register_info(outputStream *st, const void *context) {
376 ShouldNotCallThis();
377 }
378
379 /////////////////////////////////////////////////////////////////////////////
380 // Stubs for things that would be in bsd_zero.s if it existed.
381 // You probably want to disassemble these monkeys to check they're ok.
382
383 extern "C" {
384 int SpinPause() {
385 return 1;
386 }
387
388 void _Copy_conjoint_jshorts_atomic(jshort* from, jshort* to, size_t count) {
389 if (from > to) {
390 jshort *end = from + count;
391 while (from < end)
392 *(to++) = *(from++);
393 }
394 else if (from < to) {
395 jshort *end = from;
396 from += count - 1;
397 to += count - 1;
398 while (from >= end)
399 *(to--) = *(from--);
400 }
401 }
402 void _Copy_conjoint_jints_atomic(jint* from, jint* to, size_t count) {
403 if (from > to) {
404 jint *end = from + count;
405 while (from < end)
406 *(to++) = *(from++);
407 }
408 else if (from < to) {
409 jint *end = from;
410 from += count - 1;
411 to += count - 1;
412 while (from >= end)
413 *(to--) = *(from--);
414 }
415 }
416 void _Copy_conjoint_jlongs_atomic(jlong* from, jlong* to, size_t count) {
417 if (from > to) {
418 jlong *end = from + count;
419 while (from < end)
420 os::atomic_copy64(from++, to++);
421 }
422 else if (from < to) {
423 jlong *end = from;
424 from += count - 1;
425 to += count - 1;
426 while (from >= end)
427 os::atomic_copy64(from--, to--);
428 }
429 }
430
431 void _Copy_arrayof_conjoint_bytes(HeapWord* from,
432 HeapWord* to,
433 size_t count) {
434 memmove(to, from, count);
435 }
436 void _Copy_arrayof_conjoint_jshorts(HeapWord* from,
437 HeapWord* to,
438 size_t count) {
439 memmove(to, from, count * 2);
440 }
441 void _Copy_arrayof_conjoint_jints(HeapWord* from,
442 HeapWord* to,
443 size_t count) {
444 memmove(to, from, count * 4);
445 }
446 void _Copy_arrayof_conjoint_jlongs(HeapWord* from,
447 HeapWord* to,
448 size_t count) {
449 memmove(to, from, count * 8);
450 }
451 };
452
453 /////////////////////////////////////////////////////////////////////////////
454 // Implementations of atomic operations not supported by processors.
455 // -- http://gcc.gnu.org/onlinedocs/gcc-4.2.1/gcc/Atomic-Builtins.html
456
457 #ifndef _LP64
458 extern "C" {
459 long long unsigned int __sync_val_compare_and_swap_8(
460 volatile void *ptr,
461 long long unsigned int oldval,
462 long long unsigned int newval) {
463 ShouldNotCallThis();
464 }
465 };
466 #endif // !_LP64
467
468 #ifndef PRODUCT
469 void os::verify_stack_alignment() {
470 }
471 #endif
472
473 int os::extra_bang_size_in_bytes() {
474 // Zero does not require an additional stack bang.
475 return 0;
476 }