1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2007-2012 Nicira, Inc.
4 */
5
6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7
8 #include <linux/if_arp.h>
9 #include <linux/if_bridge.h>
10 #include <linux/if_vlan.h>
11 #include <linux/kernel.h>
12 #include <linux/llc.h>
13 #include <linux/rtnetlink.h>
14 #include <linux/skbuff.h>
15 #include <linux/openvswitch.h>
16 #include <linux/export.h>
17
18 #include <net/ip_tunnels.h>
19 #include <net/rtnetlink.h>
20
21 #include "datapath.h"
22 #include "vport.h"
23 #include "vport-internal_dev.h"
24 #include "vport-netdev.h"
25
26 static struct vport_ops ovs_netdev_vport_ops;
27
28 /* Must be called with rcu_read_lock. */
netdev_port_receive(struct sk_buff * skb)29 static void netdev_port_receive(struct sk_buff *skb)
30 {
31 struct vport *vport;
32
33 vport = ovs_netdev_get_vport(skb->dev);
34 if (unlikely(!vport))
35 goto error;
36
37 if (unlikely(skb_warn_if_lro(skb)))
38 goto error;
39
40 /* Make our own copy of the packet. Otherwise we will mangle the
41 * packet for anyone who came before us (e.g. tcpdump via AF_PACKET).
42 */
43 skb = skb_share_check(skb, GFP_ATOMIC);
44 if (unlikely(!skb))
45 return;
46
47 if (skb->dev->type == ARPHRD_ETHER)
48 skb_push_rcsum(skb, ETH_HLEN);
49
50 ovs_vport_receive(vport, skb, skb_tunnel_info(skb));
51 return;
52 error:
53 kfree_skb(skb);
54 }
55
56 /* Called with rcu_read_lock and bottom-halves disabled. */
netdev_frame_hook(struct sk_buff ** pskb)57 static rx_handler_result_t netdev_frame_hook(struct sk_buff **pskb)
58 {
59 struct sk_buff *skb = *pskb;
60
61 if (unlikely(skb->pkt_type == PACKET_LOOPBACK))
62 return RX_HANDLER_PASS;
63
64 netdev_port_receive(skb);
65 return RX_HANDLER_CONSUMED;
66 }
67
get_dpdev(const struct datapath * dp)68 static struct net_device *get_dpdev(const struct datapath *dp)
69 {
70 struct vport *local;
71
72 local = ovs_vport_ovsl(dp, OVSP_LOCAL);
73 return local->dev;
74 }
75
ovs_netdev_link(struct vport * vport,bool tunnel)76 struct vport *ovs_netdev_link(struct vport *vport, bool tunnel)
77 {
78 int err;
79
80 if (WARN_ON_ONCE(!vport->dev)) {
81 err = -ENODEV;
82 goto error_free_vport;
83 }
84
85 rtnl_lock();
86 /* Do not link devices that are not registered to avoid a potential
87 * race with the NETDEV_UNREGISTER notification in dp_device_event().
88 */
89 if (vport->dev->reg_state != NETREG_REGISTERED) {
90 err = -ENODEV;
91 goto error_put_unlock;
92 }
93
94 err = netdev_master_upper_dev_link(vport->dev,
95 get_dpdev(vport->dp),
96 NULL, NULL, NULL);
97 if (err)
98 goto error_put_unlock;
99
100 err = netdev_rx_handler_register(vport->dev, netdev_frame_hook,
101 vport);
102 if (err)
103 goto error_master_upper_dev_unlink;
104
105 dev_disable_lro(vport->dev);
106 dev_set_promiscuity(vport->dev, 1);
107 vport->dev->priv_flags |= IFF_OVS_DATAPATH;
108 rtnl_unlock();
109
110 return vport;
111
112 error_master_upper_dev_unlink:
113 netdev_upper_dev_unlink(vport->dev, get_dpdev(vport->dp));
114 error_put_unlock:
115 if (tunnel && vport->dev->reg_state == NETREG_REGISTERED)
116 rtnl_delete_link(vport->dev, 0, NULL);
117 netdev_put(vport->dev, &vport->dev_tracker);
118 rtnl_unlock();
119 error_free_vport:
120 ovs_vport_free(vport);
121 return ERR_PTR(err);
122 }
123 EXPORT_SYMBOL_GPL(ovs_netdev_link);
124
netdev_create(const struct vport_parms * parms)125 static struct vport *netdev_create(const struct vport_parms *parms)
126 {
127 struct vport *vport;
128 int err;
129
130 vport = ovs_vport_alloc(0, &ovs_netdev_vport_ops, parms);
131 if (IS_ERR(vport))
132 return vport;
133
134 vport->dev = dev_get_by_name(ovs_dp_get_net(vport->dp), parms->name);
135 if (!vport->dev) {
136 err = -ENODEV;
137 goto error_free_vport;
138 }
139 netdev_tracker_alloc(vport->dev, &vport->dev_tracker, GFP_KERNEL);
140
141 /* Ensure that the provided name is not an alias. */
142 if (strcmp(parms->name, ovs_vport_name(vport))) {
143 err = -ENODEV;
144 goto error_put;
145 }
146
147 if (vport->dev->flags & IFF_LOOPBACK ||
148 (vport->dev->type != ARPHRD_ETHER &&
149 vport->dev->type != ARPHRD_NONE) ||
150 ovs_is_internal_dev(vport->dev)) {
151 err = -EINVAL;
152 goto error_put;
153 }
154
155 return ovs_netdev_link(vport, false);
156 error_put:
157 netdev_put(vport->dev, &vport->dev_tracker);
158 error_free_vport:
159 ovs_vport_free(vport);
160 return ERR_PTR(err);
161 }
162
vport_netdev_free(struct rcu_head * rcu)163 static void vport_netdev_free(struct rcu_head *rcu)
164 {
165 struct vport *vport = container_of(rcu, struct vport, rcu);
166
167 netdev_put(vport->dev, &vport->dev_tracker);
168 ovs_vport_free(vport);
169 }
170
ovs_netdev_detach_dev(struct vport * vport)171 void ovs_netdev_detach_dev(struct vport *vport)
172 {
173 ASSERT_RTNL();
174 netdev_rx_handler_unregister(vport->dev);
175 netdev_upper_dev_unlink(vport->dev,
176 netdev_master_upper_dev_get(vport->dev));
177 dev_set_promiscuity(vport->dev, -1);
178
179 /* paired with smp_mb() in netdev_destroy() */
180 smp_wmb();
181
182 vport->dev->priv_flags &= ~IFF_OVS_DATAPATH;
183 }
184
netdev_destroy(struct vport * vport)185 static void netdev_destroy(struct vport *vport)
186 {
187 /* When called from ovs_db_notify_wq() after a dp_device_event(), the
188 * port has already been detached, so we can avoid taking the RTNL by
189 * checking this first.
190 */
191 if (netif_is_ovs_port(vport->dev)) {
192 rtnl_lock();
193 /* Check again while holding the lock to ensure we don't race
194 * with the netdev notifier and detach twice.
195 */
196 if (netif_is_ovs_port(vport->dev))
197 ovs_netdev_detach_dev(vport);
198 rtnl_unlock();
199 }
200
201 /* paired with smp_wmb() in ovs_netdev_detach_dev() */
202 smp_mb();
203
204 call_rcu(&vport->rcu, vport_netdev_free);
205 }
206
ovs_netdev_tunnel_destroy(struct vport * vport)207 void ovs_netdev_tunnel_destroy(struct vport *vport)
208 {
209 rtnl_lock();
210 if (netif_is_ovs_port(vport->dev))
211 ovs_netdev_detach_dev(vport);
212
213 /* We can be invoked by both explicit vport deletion and
214 * underlying netdev deregistration; delete the link only
215 * if it's not already shutting down.
216 */
217 if (vport->dev->reg_state == NETREG_REGISTERED)
218 rtnl_delete_link(vport->dev, 0, NULL);
219
220 /* We can't put the device reference yet, since it can still be in
221 * use, but rtnl_unlock()->netdev_run_todo() will block until all
222 * the references are released, so the RCU call must be before it.
223 */
224 call_rcu(&vport->rcu, vport_netdev_free);
225 rtnl_unlock();
226 }
227 EXPORT_SYMBOL_GPL(ovs_netdev_tunnel_destroy);
228
229 /* Returns null if this device is not attached to a datapath. */
ovs_netdev_get_vport(struct net_device * dev)230 struct vport *ovs_netdev_get_vport(struct net_device *dev)
231 {
232 if (likely(netif_is_ovs_port(dev)))
233 return (struct vport *)
234 rcu_dereference_rtnl(dev->rx_handler_data);
235 else
236 return NULL;
237 }
238
239 static struct vport_ops ovs_netdev_vport_ops = {
240 .type = OVS_VPORT_TYPE_NETDEV,
241 .create = netdev_create,
242 .destroy = netdev_destroy,
243 .send = dev_queue_xmit,
244 };
245
ovs_netdev_init(void)246 int __init ovs_netdev_init(void)
247 {
248 return ovs_vport_ops_register(&ovs_netdev_vport_ops);
249 }
250
ovs_netdev_exit(void)251 void ovs_netdev_exit(void)
252 {
253 ovs_vport_ops_unregister(&ovs_netdev_vport_ops);
254 }
255