Skip to content

Commit

Permalink
8309475: Test java/foreign/TestByteBuffer.java fails: a problem with …
Browse files Browse the repository at this point in the history
…msync (aix)

Backport-of: 395fc78880a91eeb06a08c1abf6905d580a650c0
  • Loading branch information
Tyler Steele authored and TheRealMDoerr committed Aug 28, 2023
1 parent 1f5ba7a commit 2408df2
Show file tree
Hide file tree
Showing 3 changed files with 210 additions and 25 deletions.
210 changes: 210 additions & 0 deletions src/java.base/aix/native/libnio/MappedMemoryUtils.c
Original file line number Diff line number Diff line change
@@ -0,0 +1,210 @@
/*
* Copyright (c) 2001, 2023, 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
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* 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.
*/

#include "jni.h"
#include "jni_util.h"
#include "jvm.h"
#include "jlong.h"
#include "java_nio_MappedMemoryUtils.h"
#include <assert.h>
#include <sys/mman.h>
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <sys/procfs.h>
#include <unistd.h>

typedef char mincore_vec_t;

static long calculate_number_of_pages_in_range(void* address, size_t len, size_t pagesize) {
uintptr_t address_unaligned = (uintptr_t) address;
uintptr_t address_aligned = address_unaligned & (~(pagesize - 1));
size_t len2 = len + (address_unaligned - address_aligned);
long numPages = (len2 + pagesize - 1) / pagesize;
return numPages;
}

JNIEXPORT jboolean JNICALL
Java_java_nio_MappedMemoryUtils_isLoaded0(JNIEnv *env, jobject obj, jlong address,
jlong len, jlong numPages)
{
jboolean loaded = JNI_TRUE;
int result = 0;
long i = 0;
void *a = (void *) jlong_to_ptr(address);
mincore_vec_t* vec = NULL;

/* See JDK-8186665 */
size_t pagesize = (size_t)sysconf(_SC_PAGESIZE);
if ((long)pagesize == -1) {
return JNI_FALSE;
}
numPages = (jlong) calculate_number_of_pages_in_range(a, len, pagesize);

/* Include space for one sentinel byte at the end of the buffer
* to catch overflows. */
vec = (mincore_vec_t*) malloc(numPages + 1);

if (vec == NULL) {
JNU_ThrowOutOfMemoryError(env, NULL);
return JNI_FALSE;
}

vec[numPages] = '\x7f'; /* Write sentinel. */
result = mincore(a, (size_t)len, vec);
assert(vec[numPages] == '\x7f'); /* Check sentinel. */

if (result == -1) {
JNU_ThrowIOExceptionWithLastError(env, "mincore failed");
free(vec);
return JNI_FALSE;
}

for (i=0; i<numPages; i++) {
if (vec[i] == 0) {
loaded = JNI_FALSE;
break;
}
}
free(vec);
return loaded;
}


JNIEXPORT void JNICALL
Java_java_nio_MappedMemoryUtils_load0(JNIEnv *env, jobject obj, jlong address,
jlong len)
{
char *a = (char *)jlong_to_ptr(address);
int result = madvise((caddr_t)a, (size_t)len, MADV_WILLNEED);
if (result == -1) {
JNU_ThrowIOExceptionWithMessageAndLastError(env, "madvise with advise MADV_WILLNEED failed");
}
}

JNIEXPORT void JNICALL
Java_java_nio_MappedMemoryUtils_unload0(JNIEnv *env, jobject obj, jlong address,
jlong len)
{
char *a = (char *)jlong_to_ptr(address);
int result = madvise((caddr_t)a, (size_t)len, MADV_DONTNEED);
if (result == -1) {
JNU_ThrowIOExceptionWithMessageAndLastError(env, "madvise with advise MADV_DONTNEED failed");
}
}

static void set_error_if_shared(JNIEnv* env, prmap_t* map_entry)
{
if (map_entry->pr_mflags & MA_SHARED) {
// MA_SHARED => MAP_SHARED => !MAP_PRIVATE. This error is valid and should be thrown.
JNU_ThrowIOExceptionWithMessageAndLastError(env, "msync with parameter MS_SYNC failed (MAP_SHARED)");
return;
} else {
// O.W. MAP_PRIVATE or no flag was specified and EINVAL is the expected behaviour.
return;
}
}

static void check_proc_map_array(JNIEnv* env, FILE* proc_file, prmap_t* map_entry, void* end_address)
{
while (!feof(proc_file)) {
memset(map_entry, '\0', sizeof(prmap_t));
fread((char*)map_entry, sizeof(prmap_t), 1, proc_file);
if (ferror(proc_file)) {
JNU_ThrowIOExceptionWithMessageAndLastError(env,
"msync with parameter MS_SYNC failed (could not read /proc/<pid>/map)");
return;
} else if (map_entry->pr_vaddr <= end_address &&
(uint64_t)end_address <= (uint64_t)map_entry->pr_vaddr + map_entry->pr_size) {
set_error_if_shared(env, map_entry);
return;
}
}
JNU_ThrowIOExceptionWithMessageAndLastError(env,
"msync with parameter MS_SYNC failed (address not found)");
}

// '/proc/' + <pid> + '/map' + '\0'
#define PFNAME_LEN 32
static void check_aix_einval(JNIEnv* env, void* end_address)
{
// If EINVAL is set for a mmap address on AIX, additional validation is required.
// AIX will set EINVAL when msync is called on a mmap address that didn't receive MAP_SHARED
// as a flag (since MAP_PRIVATE is the default).
// https://www.ibm.com/docs/en/aix/7.2?topic=m-msync-subroutine

FILE* proc_file;
{
char* fname = (char*) malloc(sizeof(char) * PFNAME_LEN);
pid_t the_pid = getpid();
jio_snprintf(fname, PFNAME_LEN, "/proc/%d/map", the_pid);
proc_file = fopen(fname, "r");
free(fname);
}
if (!proc_file) {
JNU_ThrowIOExceptionWithMessageAndLastError(env,
"msync with parameter MS_SYNC failed (could not open /proc/<pid>/map)");
return;
}
{
prmap_t* map_entry = (prmap_t*) malloc(sizeof(prmap_t));
check_proc_map_array(env, proc_file, map_entry, end_address);
free(map_entry);
}
fclose(proc_file);
}

// Normally we would just let msync handle this, but since we'll be (potentially) ignoring
// the error code returned by msync, we check the args before the call instead.
static int validate_msync_address(size_t address)
{
size_t pagesize = (size_t)sysconf(_SC_PAGESIZE);
if (address % pagesize != 0) {
errno = EINVAL;
return -1;
}
return 0;
}

JNIEXPORT void JNICALL
Java_java_nio_MappedMemoryUtils_force0(JNIEnv *env, jobject obj, jobject fdo,
jlong address, jlong len)
{
void* a = (void *)jlong_to_ptr(address);
if (validate_msync_address((size_t)a) > 0) {
JNU_ThrowIOExceptionWithMessageAndLastError(env,
"msync with parameter MS_SYNC failed (arguments invalid)");
return;
}
int result = msync(a, (size_t)len, MS_SYNC);
if (result == -1) {
void* end_address = (void*)jlong_to_ptr(address + len);
if (errno == EINVAL) {
check_aix_einval(env, end_address);
return;
}
JNU_ThrowIOExceptionWithMessageAndLastError(env, "msync with parameter MS_SYNC failed");
}
}
23 changes: 0 additions & 23 deletions src/java.base/unix/native/libnio/MappedMemoryUtils.c
Original file line number Diff line number Diff line change
Expand Up @@ -33,27 +33,13 @@
#include <stddef.h>
#include <stdlib.h>

#ifdef _AIX
#include <unistd.h>
#endif

/* Output type for mincore(2) */
#ifdef __linux__
typedef unsigned char mincore_vec_t;
#else
typedef char mincore_vec_t;
#endif

#ifdef _AIX
static long calculate_number_of_pages_in_range(void* address, size_t len, size_t pagesize) {
uintptr_t address_unaligned = (uintptr_t) address;
uintptr_t address_aligned = address_unaligned & (~(pagesize - 1));
size_t len2 = len + (address_unaligned - address_aligned);
long numPages = (len2 + pagesize - 1) / pagesize;
return numPages;
}
#endif

JNIEXPORT jboolean JNICALL
Java_java_nio_MappedMemoryUtils_isLoaded0(JNIEnv *env, jobject obj, jlong address,
jlong len, jlong numPages)
Expand All @@ -64,15 +50,6 @@ Java_java_nio_MappedMemoryUtils_isLoaded0(JNIEnv *env, jobject obj, jlong addres
void *a = (void *) jlong_to_ptr(address);
mincore_vec_t* vec = NULL;

#ifdef _AIX
/* See JDK-8186665 */
size_t pagesize = (size_t)sysconf(_SC_PAGESIZE);
if ((long)pagesize == -1) {
return JNI_FALSE;
}
numPages = (jlong) calculate_number_of_pages_in_range(a, len, pagesize);
#endif

/* Include space for one sentinel byte at the end of the buffer
* to catch overflows. */
vec = (mincore_vec_t*) malloc(numPages + 1);
Expand Down
2 changes: 0 additions & 2 deletions test/jdk/ProblemList.txt
Original file line number Diff line number Diff line change
Expand Up @@ -765,8 +765,6 @@ jdk/jfr/tool/TestView.java 8309238 macosx-x

# jdk_foreign

java/foreign/TestByteBuffer.java 8309475 aix-ppc64

############################################################################
# Client manual tests

Expand Down

1 comment on commit 2408df2

@openjdk-notifier
Copy link

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Please sign in to comment.