1 // SPDX-License-Identifier: GPL-2.0-only 2 #include <linux/etherdevice.h> 3 #include "ipvlan.h" 4 #include <linux/if_vlan.h> 5 #include <linux/if_tap.h> 6 #include <linux/interrupt.h> 7 #include <linux/nsproxy.h> 8 #include <linux/compat.h> 9 #include <linux/if_tun.h> 10 #include <linux/module.h> 11 #include <linux/skbuff.h> 12 #include <linux/cache.h> 13 #include <linux/sched.h> 14 #include <linux/types.h> 15 #include <linux/slab.h> 16 #include <linux/wait.h> 17 #include <linux/cdev.h> 18 #include <linux/idr.h> 19 #include <linux/fs.h> 20 #include <linux/uio.h> 21 22 #include <net/net_namespace.h> 23 #include <net/rtnetlink.h> 24 #include <net/sock.h> 25 #include <linux/virtio_net.h> 26 27 #define TUN_OFFLOADS (NETIF_F_HW_CSUM | NETIF_F_TSO_ECN | NETIF_F_TSO | \ 28 NETIF_F_TSO6) 29 30 static dev_t ipvtap_major; 31 static struct cdev ipvtap_cdev; 32 33 static const void *ipvtap_net_namespace(const struct device *d) 34 { 35 const struct net_device *dev = to_net_dev(d->parent); 36 return dev_net(dev); 37 } 38 39 static struct class ipvtap_class = { 40 .name = "ipvtap", 41 .ns_type = &net_ns_type_operations, 42 .namespace = ipvtap_net_namespace, 43 }; 44 45 struct ipvtap_dev { 46 struct ipvl_dev vlan; 47 struct tap_dev tap; 48 }; 49 50 static void ipvtap_count_tx_dropped(struct tap_dev *tap) 51 { 52 struct ipvtap_dev *vlantap = container_of(tap, struct ipvtap_dev, tap); 53 struct ipvl_dev *vlan = &vlantap->vlan; 54 55 this_cpu_inc(vlan->pcpu_stats->tx_drps); 56 } 57 58 static void ipvtap_count_rx_dropped(struct tap_dev *tap) 59 { 60 struct ipvtap_dev *vlantap = container_of(tap, struct ipvtap_dev, tap); 61 struct ipvl_dev *vlan = &vlantap->vlan; 62 63 ipvlan_count_rx(vlan, 0, 0, 0); 64 } 65 66 static void ipvtap_update_features(struct tap_dev *tap, 67 netdev_features_t features) 68 { 69 struct ipvtap_dev *vlantap = container_of(tap, struct ipvtap_dev, tap); 70 struct ipvl_dev *vlan = &vlantap->vlan; 71 72 vlan->sfeatures = features; 73 netdev_update_features(vlan->dev); 74 } 75 76 static int ipvtap_newlink(struct net *src_net, struct net_device *dev, 77 struct nlattr *tb[], struct nlattr *data[], 78 struct netlink_ext_ack *extack) 79 { 80 struct ipvtap_dev *vlantap = netdev_priv(dev); 81 int err; 82 83 INIT_LIST_HEAD(&vlantap->tap.queue_list); 84 85 /* Since macvlan supports all offloads by default, make 86 * tap support all offloads also. 87 */ 88 vlantap->tap.tap_features = TUN_OFFLOADS; 89 vlantap->tap.count_tx_dropped = ipvtap_count_tx_dropped; 90 vlantap->tap.update_features = ipvtap_update_features; 91 vlantap->tap.count_rx_dropped = ipvtap_count_rx_dropped; 92 93 err = netdev_rx_handler_register(dev, tap_handle_frame, &vlantap->tap); 94 if (err) 95 return err; 96 97 /* Don't put anything that may fail after macvlan_common_newlink 98 * because we can't undo what it does. 99 */ 100 err = ipvlan_link_new(src_net, dev, tb, data, extack); 101 if (err) { 102 netdev_rx_handler_unregister(dev); 103 return err; 104 } 105 106 vlantap->tap.dev = vlantap->vlan.dev; 107 108 return err; 109 } 110 111 static void ipvtap_dellink(struct net_device *dev, 112 struct list_head *head) 113 { 114 struct ipvtap_dev *vlan = netdev_priv(dev); 115 116 netdev_rx_handler_unregister(dev); 117 tap_del_queues(&vlan->tap); 118 ipvlan_link_delete(dev, head); 119 } 120 121 static void ipvtap_setup(struct net_device *dev) 122 { 123 ipvlan_link_setup(dev); 124 dev->tx_queue_len = TUN_READQ_SIZE; 125 dev->priv_flags &= ~IFF_NO_QUEUE; 126 } 127 128 static struct rtnl_link_ops ipvtap_link_ops __read_mostly = { 129 .kind = "ipvtap", 130 .setup = ipvtap_setup, 131 .newlink = ipvtap_newlink, 132 .dellink = ipvtap_dellink, 133 .priv_size = sizeof(struct ipvtap_dev), 134 }; 135 136 static int ipvtap_device_event(struct notifier_block *unused, 137 unsigned long event, void *ptr) 138 { 139 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 140 struct ipvtap_dev *vlantap; 141 struct device *classdev; 142 dev_t devt; 143 int err; 144 char tap_name[IFNAMSIZ]; 145 146 if (dev->rtnl_link_ops != &ipvtap_link_ops) 147 return NOTIFY_DONE; 148 149 snprintf(tap_name, IFNAMSIZ, "tap%d", dev->ifindex); 150 vlantap = netdev_priv(dev); 151 152 switch (event) { 153 case NETDEV_REGISTER: 154 /* Create the device node here after the network device has 155 * been registered but before register_netdevice has 156 * finished running. 157 */ 158 err = tap_get_minor(ipvtap_major, &vlantap->tap); 159 if (err) 160 return notifier_from_errno(err); 161 162 devt = MKDEV(MAJOR(ipvtap_major), vlantap->tap.minor); 163 classdev = device_create(&ipvtap_class, &dev->dev, devt, 164 dev, "%s", tap_name); 165 if (IS_ERR(classdev)) { 166 tap_free_minor(ipvtap_major, &vlantap->tap); 167 return notifier_from_errno(PTR_ERR(classdev)); 168 } 169 err = sysfs_create_link(&dev->dev.kobj, &classdev->kobj, 170 tap_name); 171 if (err) 172 return notifier_from_errno(err); 173 break; 174 case NETDEV_UNREGISTER: 175 /* vlan->minor == 0 if NETDEV_REGISTER above failed */ 176 if (vlantap->tap.minor == 0) 177 break; 178 sysfs_remove_link(&dev->dev.kobj, tap_name); 179 devt = MKDEV(MAJOR(ipvtap_major), vlantap->tap.minor); 180 device_destroy(&ipvtap_class, devt); 181 tap_free_minor(ipvtap_major, &vlantap->tap); 182 break; 183 case NETDEV_CHANGE_TX_QUEUE_LEN: 184 if (tap_queue_resize(&vlantap->tap)) 185 return NOTIFY_BAD; 186 break; 187 } 188 189 return NOTIFY_DONE; 190 } 191 192 static struct notifier_block ipvtap_notifier_block __read_mostly = { 193 .notifier_call = ipvtap_device_event, 194 }; 195 196 static int __init ipvtap_init(void) 197 { 198 int err; 199 200 err = tap_create_cdev(&ipvtap_cdev, &ipvtap_major, "ipvtap", 201 THIS_MODULE); 202 if (err) 203 goto out1; 204 205 err = class_register(&ipvtap_class); 206 if (err) 207 goto out2; 208 209 err = register_netdevice_notifier(&ipvtap_notifier_block); 210 if (err) 211 goto out3; 212 213 err = ipvlan_link_register(&ipvtap_link_ops); 214 if (err) 215 goto out4; 216 217 return 0; 218 219 out4: 220 unregister_netdevice_notifier(&ipvtap_notifier_block); 221 out3: 222 class_unregister(&ipvtap_class); 223 out2: 224 tap_destroy_cdev(ipvtap_major, &ipvtap_cdev); 225 out1: 226 return err; 227 } 228 module_init(ipvtap_init); 229 230 static void __exit ipvtap_exit(void) 231 { 232 rtnl_link_unregister(&ipvtap_link_ops); 233 unregister_netdevice_notifier(&ipvtap_notifier_block); 234 class_unregister(&ipvtap_class); 235 tap_destroy_cdev(ipvtap_major, &ipvtap_cdev); 236 } 237 module_exit(ipvtap_exit); 238 MODULE_ALIAS_RTNL_LINK("ipvtap"); 239 MODULE_AUTHOR("Sainath Grandhi <sainath.grandhi@intel.com>"); 240 MODULE_DESCRIPTION("IP-VLAN based tap driver"); 241 MODULE_LICENSE("GPL"); 242