def cancelAll(self):
cancel = self.cancel<EOL>result = []<EOL>for block, _ in self._submitted.itervalues():<EOL><INDENT>try:<EOL><INDENT>result.append(cancel(block))<EOL><DEDENT>except OSError as exc:<EOL><INDENT>if exc.errno != errno.EINVAL:<EOL><INDENT>raise<EOL><DEDENT><DEDENT><DEDENT>return result<EOL>
Cancel all submitted IO blocks.

Blocks until all submitted transfers have been finalised.
Submitting more transfers or processing completion events while this
method is running produces undefined behaviour.
Returns the list of values returned by individual cancellations.
See "cancel" documentation.