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-rw-r--r--drivers/net/macvtap.c255
1 files changed, 255 insertions, 0 deletions
diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c
new file mode 100644
index 000000000..d1f435788
--- /dev/null
+++ b/drivers/net/macvtap.c
@@ -0,0 +1,255 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/etherdevice.h>
+#include <linux/if_macvlan.h>
+#include <linux/if_tap.h>
+#include <linux/if_vlan.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/signal.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>
+#include <linux/skb_array.h>
+
+struct macvtap_dev {
+ struct macvlan_dev vlan;
+ struct tap_dev tap;
+};
+
+/*
+ * Variables for dealing with macvtaps device numbers.
+ */
+static dev_t macvtap_major;
+
+static const void *macvtap_net_namespace(struct device *d)
+{
+ struct net_device *dev = to_net_dev(d->parent);
+ return dev_net(dev);
+}
+
+static struct class macvtap_class = {
+ .name = "macvtap",
+ .owner = THIS_MODULE,
+ .ns_type = &net_ns_type_operations,
+ .namespace = macvtap_net_namespace,
+};
+static struct cdev macvtap_cdev;
+
+#define TUN_OFFLOADS (NETIF_F_HW_CSUM | NETIF_F_TSO_ECN | NETIF_F_TSO | \
+ NETIF_F_TSO6)
+
+static void macvtap_count_tx_dropped(struct tap_dev *tap)
+{
+ struct macvtap_dev *vlantap = container_of(tap, struct macvtap_dev, tap);
+ struct macvlan_dev *vlan = &vlantap->vlan;
+
+ this_cpu_inc(vlan->pcpu_stats->tx_dropped);
+}
+
+static void macvtap_count_rx_dropped(struct tap_dev *tap)
+{
+ struct macvtap_dev *vlantap = container_of(tap, struct macvtap_dev, tap);
+ struct macvlan_dev *vlan = &vlantap->vlan;
+
+ macvlan_count_rx(vlan, 0, 0, 0);
+}
+
+static void macvtap_update_features(struct tap_dev *tap,
+ netdev_features_t features)
+{
+ struct macvtap_dev *vlantap = container_of(tap, struct macvtap_dev, tap);
+ struct macvlan_dev *vlan = &vlantap->vlan;
+
+ vlan->set_features = features;
+ netdev_update_features(vlan->dev);
+}
+
+static int macvtap_newlink(struct net *src_net, struct net_device *dev,
+ struct nlattr *tb[], struct nlattr *data[],
+ struct netlink_ext_ack *extack)
+{
+ struct macvtap_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;
+
+ /* Register callbacks for rx/tx drops accounting and updating
+ * net_device features
+ */
+ vlantap->tap.count_tx_dropped = macvtap_count_tx_dropped;
+ vlantap->tap.count_rx_dropped = macvtap_count_rx_dropped;
+ vlantap->tap.update_features = macvtap_update_features;
+
+ 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 = macvlan_common_newlink(src_net, dev, tb, data, extack);
+ if (err) {
+ netdev_rx_handler_unregister(dev);
+ return err;
+ }
+
+ vlantap->tap.dev = vlantap->vlan.dev;
+
+ return 0;
+}
+
+static void macvtap_dellink(struct net_device *dev,
+ struct list_head *head)
+{
+ struct macvtap_dev *vlantap = netdev_priv(dev);
+
+ netdev_rx_handler_unregister(dev);
+ tap_del_queues(&vlantap->tap);
+ macvlan_dellink(dev, head);
+}
+
+static void macvtap_setup(struct net_device *dev)
+{
+ macvlan_common_setup(dev);
+ dev->tx_queue_len = TUN_READQ_SIZE;
+}
+
+static struct net *macvtap_link_net(const struct net_device *dev)
+{
+ return dev_net(macvlan_dev_real_dev(dev));
+}
+
+static struct rtnl_link_ops macvtap_link_ops __read_mostly = {
+ .kind = "macvtap",
+ .setup = macvtap_setup,
+ .newlink = macvtap_newlink,
+ .dellink = macvtap_dellink,
+ .get_link_net = macvtap_link_net,
+ .priv_size = sizeof(struct macvtap_dev),
+};
+
+static int macvtap_device_event(struct notifier_block *unused,
+ unsigned long event, void *ptr)
+{
+ struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+ struct macvtap_dev *vlantap;
+ struct device *classdev;
+ dev_t devt;
+ int err;
+ char tap_name[IFNAMSIZ];
+
+ if (dev->rtnl_link_ops != &macvtap_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(macvtap_major, &vlantap->tap);
+ if (err)
+ return notifier_from_errno(err);
+
+ devt = MKDEV(MAJOR(macvtap_major), vlantap->tap.minor);
+ classdev = device_create(&macvtap_class, &dev->dev, devt,
+ dev, "%s", tap_name);
+ if (IS_ERR(classdev)) {
+ tap_free_minor(macvtap_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(macvtap_major), vlantap->tap.minor);
+ device_destroy(&macvtap_class, devt);
+ tap_free_minor(macvtap_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 macvtap_notifier_block __read_mostly = {
+ .notifier_call = macvtap_device_event,
+};
+
+static int __init macvtap_init(void)
+{
+ int err;
+
+ err = tap_create_cdev(&macvtap_cdev, &macvtap_major, "macvtap",
+ THIS_MODULE);
+ if (err)
+ goto out1;
+
+ err = class_register(&macvtap_class);
+ if (err)
+ goto out2;
+
+ err = register_netdevice_notifier(&macvtap_notifier_block);
+ if (err)
+ goto out3;
+
+ err = macvlan_link_register(&macvtap_link_ops);
+ if (err)
+ goto out4;
+
+ return 0;
+
+out4:
+ unregister_netdevice_notifier(&macvtap_notifier_block);
+out3:
+ class_unregister(&macvtap_class);
+out2:
+ tap_destroy_cdev(macvtap_major, &macvtap_cdev);
+out1:
+ return err;
+}
+module_init(macvtap_init);
+
+static void __exit macvtap_exit(void)
+{
+ rtnl_link_unregister(&macvtap_link_ops);
+ unregister_netdevice_notifier(&macvtap_notifier_block);
+ class_unregister(&macvtap_class);
+ tap_destroy_cdev(macvtap_major, &macvtap_cdev);
+}
+module_exit(macvtap_exit);
+
+MODULE_ALIAS_RTNL_LINK("macvtap");
+MODULE_AUTHOR("Arnd Bergmann <arnd@arndb.de>");
+MODULE_LICENSE("GPL");