src/java.base/windows/classes/sun/nio/fs/WindowsFileStore.java

@@ -123,32 +123,46 @@
     public boolean isReadOnly() {
         return ((volInfo.flags() & FILE_READ_ONLY_VOLUME) != 0);
     }
 
     // read the free space info
-    private DiskFreeSpace readDiskFreeSpace() throws IOException {
+    private DiskFreeSpace readDiskFreeSpaceEx() throws IOException {
         try {
             return GetDiskFreeSpaceEx(root);
         } catch (WindowsException x) {
             x.rethrowAsIOException(root);
             return null;
         }
     }
 
+    private DiskFreeSpace readDiskFreeSpace() throws IOException {
+        try {
+            return GetDiskFreeSpace(root);
+        } catch (WindowsException x) {
+            x.rethrowAsIOException(root);
+            return null;
+        }
+    }
+
     @Override
     public long getTotalSpace() throws IOException {
-        return readDiskFreeSpace().totalNumberOfBytes();
+        return readDiskFreeSpaceEx().totalNumberOfBytes();
     }
 
     @Override
     public long getUsableSpace() throws IOException {
-        return readDiskFreeSpace().freeBytesAvailable();
+        return readDiskFreeSpaceEx().freeBytesAvailable();
+    }
+
+    @Override
+    public int getBlockSize() throws IOException {
+        return (int)readDiskFreeSpace().bytesPerSector();
     }
 
     @Override
     public long getUnallocatedSpace() throws IOException {
-        return readDiskFreeSpace().freeBytesAvailable();
+        return readDiskFreeSpaceEx().freeBytesAvailable();
     }
 
     @Override
     public <V extends FileStoreAttributeView> V getFileStoreAttributeView(Class<V> type) {
         if (type == null)

@@ -163,10 +177,12 @@
             return getTotalSpace();
         if (attribute.equals("usableSpace"))
             return getUsableSpace();
         if (attribute.equals("unallocatedSpace"))
             return getUnallocatedSpace();
+        if (attribute.equals("bytesPerSector"))
+            return getBlockSize();
         // windows specific for testing purposes
         if (attribute.equals("volume:vsn"))
             return volInfo.volumeSerialNumber();
         if (attribute.equals("volume:isRemovable"))
             return volType == DRIVE_REMOVABLE;