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::Posix::_compiler_thread_min_stack_allowed = 64 * K;

   286 size_t os::Posix::_java_thread_min_stack_allowed = 64 * K;

   287 size_t os::Posix::_vm_internal_thread_min_stack_allowed = 64 * K;

   288 

   289 size_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 

   298 static 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 

   349 address os::current_stack_base() {

   350   address bottom;

   351   size_t size;

   352   current_stack_region(&bottom, &size);

   353   return bottom + size;

   354 }

   355 

   356 size_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 

   367 void os::print_context(outputStream* st, const void* context) {

   368   ShouldNotCallThis();

   369 }

   370 

   371 void 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 

   379 extern "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

   454 extern "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

   465 void os::verify_stack_alignment() {

   466 }

   467 #endif

   468 

   469 int os::extra_bang_size_in_bytes() {

   470   // Zero does not require an additional stack bang.

   471   return 0;

   472 }