src/solaris/native/sun/nio/ch/FileDispatcherImpl.c

*** 1,7 ****
  /*
!  * Copyright (c) 2000, 2012, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
--- 1,7 ----
  /*
!  * Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
*** 21,30 ****
--- 21,34 ----
   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   * or visit www.oracle.com if you need additional information or have any
   * questions.
   */
  
+ #if defined(__linux__)
+ #define _FILE_OFFSET_BITS 64
+ #endif
+ 
  #include "jni.h"
  #include "jni_util.h"
  #include "jvm.h"
  #include "jlong.h"
  #include "sun_nio_ch_FileDispatcherImpl.h"
*** 176,185 ****
--- 180,213 ----
      return handle(env,
                    ftruncate64(fdval(env, fdo), size),
                    "Truncation failed");
  }
  
+ JNIEXPORT jint JNICALL
+ Java_sun_nio_ch_FileDispatcherImpl_allocate0(JNIEnv *env, jobject this,
+                                              jobject fdo, jlong size)
+ {
+ #if defined(__linux__)
+     /*
+      * On Linux, if the file size is being increased, then ftruncate64()
+      * will modify the metadata value of the size without actually allocating
+      * any blocks which can cause a SIGBUS error if the file is subsequently
+      * memory-mapped.
+      */
+     // Return on success or if errno is neither EOPNOTSUPP nor ENOSYS
+     int result = posix_fallocate(fdval(env, fdo), 0, size);
+     if (result == 0) {
+         return 0;
+     } else if (errno != EOPNOTSUPP && errno != ENOSYS) {
+         return handle(env, result, "Allocation failed");
+     }
+ #endif
+     return handle(env,
+                   ftruncate64(fdval(env, fdo), size),
+                   "Truncation failed");
+ }
+ 
  JNIEXPORT jlong JNICALL
  Java_sun_nio_ch_FileDispatcherImpl_size0(JNIEnv *env, jobject this, jobject fdo)
  {
      jint fd = fdval(env, fdo);
      struct stat64 fbuf;