synchronized (controller) {
testDiskChange();
BlockDeviceAPIHelper.checkBounds(this, devOffset, length);
final int sectorLength = SECTOR_LENGTH[currentSectorSize];
testAlignment(sectorLength, devOffset, length);
CHS chs = fp.getGeometry().getCHS(devOffset / sectorLength);
FloppyDeviceFactory factory;
try {
factory = FloppyDriverUtils.getFloppyDeviceFactory();
} catch (NamingException ex) {
throw (IOException) new IOException().initCause(ex);