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 = ThreadLocalStorage::get_thread_slow();
 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 }
--- EOF ---