Replace frame number with bool value

src/linux/virtio.rs

@@ -406,10 +406,8 @@ impl VirtioNetPciDevice {
 				);
 
 				match write_packet(&poll_rx_queue, &mut frame_queue, &mmap) {
-					Ok(sent) => {
-						// TODO: replace Ok(usize) with bool (if needs notification)
-						// trace!("wrote {}/{} received frames to guest memory", sent, l);
-						if sent > 0 && poll_rx_queue.lock().needs_notification(&mmap).unwrap() {
+					Ok(data_sent) => {
+						if data_sent && poll_rx_queue.lock().needs_notification(&mmap).unwrap() {
 							_delay = time::Instant::now();
 							alert.store(true, Ordering::Release);
 							irq_evtfd.write(1).unwrap();
@@ -609,7 +607,7 @@ fn write_packet(
 	rx_queue: &Arc<Mutex<Queue>>,
 	frame_queue: &mut Vec<([u8; UHYVE_NET_MTU], usize)>,
 	mmap: &GuestMemoryMmap,
-) -> Result<usize, VirtIOError> {
+) -> Result<bool, VirtIOError> {
 	let mut queue = rx_queue.lock();
 
 	if !queue.is_valid(mmap) {
@@ -662,7 +660,7 @@ fn write_packet(
 	});
 	queue.enable_notification(mmap)?;
 
-	Ok(l - frame_queue.len())
+	Ok(l - frame_queue.len() > 0)
 }
 
 fn send_available_packets(