// SPDX-License-Identifier: GPL-2.0-only#include <linux/etherdevice.h>#include "ipvlan.h"#include <linux/if_vlan.h>#include <linux/if_tap.h>#include <linux/interrupt.h>#include <linux/nsproxy.h>#include <linux/compat.h>#include <linux/if_tun.h>#include <linux/module.h>#include <linux/skbuff.h>#include <linux/cache.h>#include <linux/sched.h>#include <linux/types.h>#include <linux/slab.h>#include <linux/wait.h>#include <linux/cdev.h>#include <linux/idr.h>#include <linux/fs.h>#include <linux/uio.h> #include <net/net_namespace.h>#include <net/rtnetlink.h>#include <net/sock.h>#include <linux/virtio_net.h> #define TUN_OFFLOADS (NETIF_F_HW_CSUM | NETIF_F_TSO_ECN | NETIF_F_TSO | \		      NETIF_F_TSO6) static dev_t ipvtap_major;static struct cdev ipvtap_cdev; static const struct ns_common *ipvtap_net_namespace(const struct device *d){	const struct net_device *dev = to_net_dev(d->parent); 	return to_ns_common(dev_net(dev));} static struct class ipvtap_class = {	 .name = "ipvtap",	 .ns_type = &net_ns_type_operations,	 .namespace = ipvtap_net_namespace,}; struct ipvtap_dev {	struct ipvl_dev vlan;	struct tap_dev	  tap;}; static void ipvtap_count_tx_dropped(struct tap_dev *tap){	struct ipvtap_dev *vlantap = container_of(tap, struct ipvtap_dev, tap);	struct ipvl_dev *vlan = &vlantap->vlan; 	this_cpu_inc(vlan->pcpu_stats->tx_drps);} static void ipvtap_count_rx_dropped(struct tap_dev *tap){	struct ipvtap_dev *vlantap = container_of(tap, struct ipvtap_dev, tap);	struct ipvl_dev *vlan = &vlantap->vlan; 	ipvlan_count_rx(vlan, 0, 0, 0);} static void ipvtap_update_features(struct tap_dev *tap,				   netdev_features_t features){	struct ipvtap_dev *vlantap = container_of(tap, struct ipvtap_dev, tap);	struct ipvl_dev *vlan = &vlantap->vlan; 	vlan->sfeatures = features;	netdev_update_features(vlan->dev);} static int ipvtap_newlink(struct net_device *dev,			  struct rtnl_newlink_params *params,			  struct netlink_ext_ack *extack){	struct ipvtap_dev *vlantap = netdev_priv(dev);	int err; 	INIT_LIST_HEAD(&vlantap->tap.queue_list); 	/* Since macvlan supports all offloads by default, make	 * tap support all offloads also.	 */	vlantap->tap.tap_features = TUN_OFFLOADS;	vlantap->tap.count_tx_dropped = ipvtap_count_tx_dropped;	vlantap->tap.update_features =	ipvtap_update_features;	vlantap->tap.count_rx_dropped = ipvtap_count_rx_dropped; 	err = netdev_rx_handler_register(dev, tap_handle_frame, &vlantap->tap);	if (err)		return err; 	/* Don't put anything that may fail after macvlan_common_newlink	 * because we can't undo what it does.	 */	err = ipvlan_link_new(dev, params, extack);	if (err) {		netdev_rx_handler_unregister(dev);		return err;	} 	vlantap->tap.dev = vlantap->vlan.dev; 	return err;} static void __ipvtap_dellink(struct net *net, struct net_device *dev,			     struct list_head *head){	struct ipvtap_dev *vlantap = netdev_priv(dev); 	netdev_rx_handler_unregister(dev);	tap_del_queues(&vlantap->tap);	__ipvlan_link_delete(net, dev, head);} static void ipvtap_dellink(struct net_device *dev,			   struct list_head *head){	struct ipvtap_dev *vlantap = netdev_priv(dev);	struct ipvl_port *port = vlantap->vlan.port; 	mutex_lock(&port->pnodes_lock);	if (!vlantap->vlan.dying)		__ipvtap_dellink(dev_net(dev), dev, head);	mutex_unlock(&port->pnodes_lock);} static void ipvtap_setup(struct net_device *dev){	ipvlan_link_setup(dev);	dev->tx_queue_len = TUN_READQ_SIZE;	dev->priv_flags &= ~IFF_NO_QUEUE;} static struct rtnl_link_ops ipvtap_link_ops __read_mostly = {	.kind		= "ipvtap",	.setup		= ipvtap_setup,	.newlink	= ipvtap_newlink,	.dellink	= ipvtap_dellink,	.priv_size	= sizeof(struct ipvtap_dev),}; static int ipvtap_device_event(struct notifier_block *unused,			       unsigned long event, void *ptr){	struct net_device *dev = netdev_notifier_info_to_dev(ptr);	struct ipvtap_dev *vlantap;	struct device *classdev;	dev_t devt;	int err;	char tap_name[IFNAMSIZ]; 	if (dev->rtnl_link_ops != &ipvtap_link_ops)		return NOTIFY_DONE; 	snprintf(tap_name, IFNAMSIZ, "tap%d", dev->ifindex);	vlantap = netdev_priv(dev); 	switch (event) {	case NETDEV_REGISTER:		/* Create the device node here after the network device has		 * been registered but before register_netdevice has		 * finished running.		 */		err = tap_get_minor(ipvtap_major, &vlantap->tap);		if (err)			return notifier_from_errno(err); 		devt = MKDEV(MAJOR(ipvtap_major), vlantap->tap.minor);		classdev = device_create(&ipvtap_class, &dev->dev, devt,					 dev, "%s", tap_name);		if (IS_ERR(classdev)) {			tap_free_minor(ipvtap_major, &vlantap->tap);			return notifier_from_errno(PTR_ERR(classdev));		}		err = sysfs_create_link(&dev->dev.kobj, &classdev->kobj,					tap_name);		if (err)			return notifier_from_errno(err);		break;	case NETDEV_UNREGISTER:		/* vlan->minor == 0 if NETDEV_REGISTER above failed */		if (vlantap->tap.minor == 0)			break;		sysfs_remove_link(&dev->dev.kobj, tap_name);		devt = MKDEV(MAJOR(ipvtap_major), vlantap->tap.minor);		device_destroy(&ipvtap_class, devt);		tap_free_minor(ipvtap_major, &vlantap->tap);		break;	case NETDEV_CHANGE_TX_QUEUE_LEN:		if (tap_queue_resize(&vlantap->tap))			return NOTIFY_BAD;		break;	} 	return NOTIFY_DONE;} static struct notifier_block ipvtap_notifier_block __read_mostly = {	.notifier_call	= ipvtap_device_event,}; static int __init ipvtap_init(void){	int err; 	__ipvtap_dellink_ptr = __ipvtap_dellink; 	err = tap_create_cdev(&ipvtap_cdev, &ipvtap_major, "ipvtap",			      THIS_MODULE);	if (err)		goto out1; 	err = class_register(&ipvtap_class);	if (err)		goto out2; 	err = register_netdevice_notifier(&ipvtap_notifier_block);	if (err)		goto out3; 	err = ipvlan_link_register(&ipvtap_link_ops);	if (err)		goto out4; 	return 0; out4:	unregister_netdevice_notifier(&ipvtap_notifier_block);out3:	class_unregister(&ipvtap_class);out2:	tap_destroy_cdev(ipvtap_major, &ipvtap_cdev);out1:	__ipvtap_dellink_ptr = NULL; 	return err;}module_init(ipvtap_init); static void __exit ipvtap_exit(void){	rtnl_link_unregister(&ipvtap_link_ops);	unregister_netdevice_notifier(&ipvtap_notifier_block);	class_unregister(&ipvtap_class);	tap_destroy_cdev(ipvtap_major, &ipvtap_cdev);	__ipvtap_dellink_ptr = NULL;}module_exit(ipvtap_exit);MODULE_ALIAS_RTNL_LINK("ipvtap");MODULE_AUTHOR("Sainath Grandhi <sainath.grandhi@intel.com>");MODULE_DESCRIPTION("IP-VLAN based tap driver");MODULE_LICENSE("GPL");