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Writing a read-only direct ByteBuffer to channel fails with native transport

See original GitHub issue

Expected behavior

I can take a direct ByteBuffer where isReadOnly() is true, such as the return value of asReadOnlyBuffer() or a MappedBuffer with MapMode.READ_ONLY, pass it to Unpooled.wrappedBuffer(ByteBuffer), and write it to the channel.

Actual behavior

Works with NIO transport. When using kqueue or epoll native transport, writing to the channel fails due to UnsupportedOperationException produced by ReadOnlyByteBufferBuf.memoryAddress().

Minimal yet complete reproducer code

Bootstrap bootstrap = new Bootstrap();
bootstrap.group(new KQueueEventLoopGroup());
bootstrap.channel(KQueueSocketChannel.class);
bootstrap.handler(new ChannelInitializer<SocketChannel>() {
    @Override
    protected void initChannel(SocketChannel ch) throws Exception {
        ch.pipeline().addLast("HttpResponseDecoder", new HttpResponseDecoder());
        ch.pipeline().addLast("HttpRequestEncoder", new HttpRequestEncoder());
    }
});

final Path path = Paths.get("src/test/resources/upload.txt");
final FileChannel fileChannel = FileChannel.open(path, StandardOpenOption.READ);

final ByteBuffer dst = ByteBuffer.allocateDirect((int) fileChannel.size());
fileChannel.read(dst, 0);
dst.flip();

bootstrap.connect("httpbin.org", 80).addListener(new ChannelFutureListener() {
    @Override
    public void operationComplete(ChannelFuture future) throws Exception {
        final Channel channel = future.channel();
        DefaultHttpHeaders headers = new DefaultHttpHeaders();
        headers.add("Content-Length", fileChannel.size());
        DefaultHttpRequest req = new DefaultHttpRequest(HttpVersion.HTTP_1_1, HttpMethod.POST, "/post", headers);
        channel.write(req);
        channel.write(Unpooled.wrappedBuffer(dst.asReadOnlyBuffer()));
        channel.writeAndFlush(DefaultLastHttpContent.EMPTY_LAST_CONTENT).addListener(new GenericFutureListener<Future<? super Void>>() {
            @Override
            public void operationComplete(Future<? super Void> future) throws Exception {
                if (!future.isSuccess()) {
                    future.cause().printStackTrace();
                }
            }
        });
    }
});

The above code prints this stack trace when run:

io.netty.channel.socket.ChannelOutputShutdownException: Channel output shutdown
	at io.netty.channel.AbstractChannel$AbstractUnsafe.shutdownOutput(AbstractChannel.java:641)
	at io.netty.channel.AbstractChannel$AbstractUnsafe.flush0(AbstractChannel.java:948)
	at io.netty.channel.AbstractChannel$AbstractUnsafe.flush(AbstractChannel.java:901)
	at io.netty.channel.DefaultChannelPipeline$HeadContext.flush(DefaultChannelPipeline.java:1374)
	at io.netty.channel.AbstractChannelHandlerContext.invokeFlush0(AbstractChannelHandlerContext.java:776)
	at io.netty.channel.AbstractChannelHandlerContext.invokeFlush(AbstractChannelHandlerContext.java:768)
	at io.netty.channel.AbstractChannelHandlerContext.flush(AbstractChannelHandlerContext.java:749)
	at io.netty.channel.ChannelOutboundHandlerAdapter.flush(ChannelOutboundHandlerAdapter.java:115)
	at io.netty.channel.AbstractChannelHandlerContext.invokeFlush0(AbstractChannelHandlerContext.java:776)
	at io.netty.channel.AbstractChannelHandlerContext.invokeWriteAndFlush(AbstractChannelHandlerContext.java:802)
	at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:814)
	at io.netty.channel.AbstractChannelHandlerContext.writeAndFlush(AbstractChannelHandlerContext.java:794)
	at io.netty.channel.AbstractChannelHandlerContext.writeAndFlush(AbstractChannelHandlerContext.java:831)
	at io.netty.channel.DefaultChannelPipeline.writeAndFlush(DefaultChannelPipeline.java:1049)
	at io.netty.channel.AbstractChannel.writeAndFlush(AbstractChannel.java:300)
	at test.operationComplete(test)
	at test.operationComplete(test)
	at io.netty.util.concurrent.DefaultPromise.notifyListener0(DefaultPromise.java:507)
	at io.netty.util.concurrent.DefaultPromise.notifyListeners0(DefaultPromise.java:500)
	at io.netty.util.concurrent.DefaultPromise.notifyListenersNow(DefaultPromise.java:479)
	at io.netty.util.concurrent.DefaultPromise.notifyListeners(DefaultPromise.java:420)
	at io.netty.util.concurrent.DefaultPromise.trySuccess(DefaultPromise.java:104)
	at io.netty.channel.DefaultChannelPromise.trySuccess(DefaultChannelPromise.java:84)
	at io.netty.channel.kqueue.AbstractKQueueChannel$AbstractKQueueUnsafe.fulfillConnectPromise(AbstractKQueueChannel.java:593)
	at io.netty.channel.kqueue.AbstractKQueueChannel$AbstractKQueueUnsafe.finishConnect(AbstractKQueueChannel.java:631)
	at io.netty.channel.kqueue.AbstractKQueueChannel$AbstractKQueueUnsafe.writeReady(AbstractKQueueChannel.java:434)
	at io.netty.channel.kqueue.KQueueEventLoop.processReady(KQueueEventLoop.java:192)
	at io.netty.channel.kqueue.KQueueEventLoop.run(KQueueEventLoop.java:269)
	at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:886)
	at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
	at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.UnsupportedOperationException
	at io.netty.buffer.ReadOnlyByteBufferBuf.memoryAddress(ReadOnlyByteBufferBuf.java:467)
	at io.netty.channel.unix.IovArray.add(IovArray.java:96)
	at io.netty.channel.unix.IovArray.processMessage(IovArray.java:191)
	at io.netty.channel.ChannelOutboundBuffer.forEachFlushedMessage(ChannelOutboundBuffer.java:762)
	at io.netty.channel.kqueue.AbstractKQueueStreamChannel.doWriteMultiple(AbstractKQueueStreamChannel.java:343)
	at io.netty.channel.kqueue.AbstractKQueueStreamChannel.doWrite(AbstractKQueueStreamChannel.java:270)
	at io.netty.channel.AbstractChannel$AbstractUnsafe.flush0(AbstractChannel.java:934)
	... 29 more