1 /*
2 * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 #include "jni.h"
27 #include "jni_util.h"
28 #include "jvm.h"
29 #include "jlong.h"
30 #include <sys/mman.h>
31 #include <stddef.h>
32 #include <stdlib.h>
33
34 #include "JNIHelp.h"
35
36 #define NATIVE_METHOD(className, functionName, signature) \
37 { #functionName, signature, (void*)(Java_java_nio_ ## className ## _ ## functionName) }
38
39 JNIEXPORT jboolean JNICALL
Java_java_nio_MappedByteBuffer_isLoaded0(JNIEnv * env,jobject obj,jlong address,jlong len,jint numPages)40 Java_java_nio_MappedByteBuffer_isLoaded0(JNIEnv *env, jobject obj, jlong address,
41 jlong len, jint numPages)
42 {
43 jboolean loaded = JNI_TRUE;
44 int result = 0;
45 int i = 0;
46 void *a = (void *) jlong_to_ptr(address);
47 #ifdef __linux__
48 unsigned char *vec = (unsigned char *)malloc(numPages * sizeof(char));
49 #else
50 char *vec = (char *)malloc(numPages * sizeof(char));
51 #endif
52
53 if (vec == NULL) {
54 JNU_ThrowOutOfMemoryError(env, NULL);
55 return JNI_FALSE;
56 }
57
58 result = mincore(a, (size_t)len, vec);
59 if (result == -1) {
60 JNU_ThrowIOExceptionWithLastError(env, "mincore failed");
61 free(vec);
62 return JNI_FALSE;
63 }
64
65 for (i=0; i<numPages; i++) {
66 if (vec[i] == 0) {
67 loaded = JNI_FALSE;
68 break;
69 }
70 }
71 free(vec);
72 return loaded;
73 }
74
75
76 JNIEXPORT void JNICALL
Java_java_nio_MappedByteBuffer_load0(JNIEnv * env,jobject obj,jlong address,jlong len)77 Java_java_nio_MappedByteBuffer_load0(JNIEnv *env, jobject obj, jlong address,
78 jlong len)
79 {
80 char *a = (char *)jlong_to_ptr(address);
81 int result = madvise((caddr_t)a, (size_t)len, MADV_WILLNEED);
82 if (result == -1) {
83 JNU_ThrowIOExceptionWithLastError(env, "madvise failed");
84 }
85 }
86
87
88 JNIEXPORT void JNICALL
Java_java_nio_MappedByteBuffer_force0(JNIEnv * env,jobject obj,jobject fdo,jlong address,jlong len)89 Java_java_nio_MappedByteBuffer_force0(JNIEnv *env, jobject obj, jobject fdo,
90 jlong address, jlong len)
91 {
92 void* a = (void *)jlong_to_ptr(address);
93 int result = msync(a, (size_t)len, MS_SYNC);
94 if (result == -1) {
95 JNU_ThrowIOExceptionWithLastError(env, "msync failed");
96 }
97 }
98
99
100 static JNINativeMethod gMethods[] = {
101 NATIVE_METHOD(MappedByteBuffer, isLoaded0, "(JJI)Z"),
102 NATIVE_METHOD(MappedByteBuffer, load0, "(JJ)V"),
103 NATIVE_METHOD(MappedByteBuffer, force0, "(Ljava/io/FileDescriptor;JJ)V"),
104 };
105
register_java_nio_MappedByteBuffer(JNIEnv * env)106 void register_java_nio_MappedByteBuffer(JNIEnv* env) {
107 jniRegisterNativeMethods(env, "java/nio/MappedByteBuffer", gMethods, NELEM(gMethods));
108 }
109