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

source code of linux/drivers/net/ipvlan/ipvtap.c