drivers/net/virtio_net.c

Source file repositories/reference/linux-study-clean/drivers/net/virtio_net.c

File Facts

System
Linux kernel
Corpus path
drivers/net/virtio_net.c
Extension
.c
Size
194142 bytes
Lines
7302
Domain
Driver Families
Bucket
drivers/net
Inferred role
Driver Families: operation-table or driver-model contract
Status
pattern implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

static const struct net_device_ops virtnet_netdev = {
	.ndo_open            = virtnet_open,
	.ndo_stop   	     = virtnet_close,
	.ndo_start_xmit      = start_xmit,
	.ndo_validate_addr   = eth_validate_addr,
	.ndo_set_mac_address = virtnet_set_mac_address,
	.ndo_set_rx_mode     = virtnet_set_rx_mode,
	.ndo_get_stats64     = virtnet_stats,
	.ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
	.ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
	.ndo_bpf		= virtnet_xdp,
	.ndo_xdp_xmit		= virtnet_xdp_xmit,
	.ndo_xsk_wakeup         = virtnet_xsk_wakeup,
	.ndo_features_check	= virtnet_features_check,
	.ndo_get_phys_port_name	= virtnet_get_phys_port_name,
	.ndo_set_features	= virtnet_set_features,
	.ndo_tx_timeout		= virtnet_tx_timeout,
};

static void virtnet_config_changed_work(struct work_struct *work)
{
	struct virtnet_info *vi =
		container_of(work, struct virtnet_info, config_work);
	u16 v;

	if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS,
				 struct virtio_net_config, status, &v) < 0)
		return;

	if (v & VIRTIO_NET_S_ANNOUNCE) {
		netdev_notify_peers(vi->dev);
		virtnet_ack_link_announce(vi);
	}

	/* Ignore unknown (future) status bits */
	v &= VIRTIO_NET_S_LINK_UP;

	if (vi->status == v)
		return;

	vi->status = v;

	if (vi->status & VIRTIO_NET_S_LINK_UP) {
		virtnet_update_settings(vi);
		netif_carrier_on(vi->dev);
		netif_tx_wake_all_queues(vi->dev);
	} else {
		netif_carrier_off(vi->dev);
		netif_tx_stop_all_queues(vi->dev);
	}
}

static void virtnet_config_changed(struct virtio_device *vdev)
{
	struct virtnet_info *vi = vdev->priv;

	schedule_work(&vi->config_work);
}

static void virtnet_free_queues(struct virtnet_info *vi)
{
	int i;

	for (i = 0; i < vi->max_queue_pairs; i++) {
		__netif_napi_del(&vi->rq[i].napi);
		__netif_napi_del(&vi->sq[i].napi);
	}

	/* We called __netif_napi_del(),
	 * we need to respect an RCU grace period before freeing vi->rq
	 */
	synchronize_net();

	kfree(vi->rq);
	kfree(vi->sq);
	kfree(vi->ctrl);
}

static void _free_receive_bufs(struct virtnet_info *vi)
{
	struct bpf_prog *old_prog;
	int i;

	for (i = 0; i < vi->max_queue_pairs; i++) {
		while (vi->rq[i].pages)
			__free_pages(get_a_page(&vi->rq[i], GFP_KERNEL), 0);

		old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
		RCU_INIT_POINTER(vi->rq[i].xdp_prog, NULL);
		if (old_prog)

Annotation

Implementation Notes