xref: /linux/net/openvswitch/vport-netdev.c (revision 23710925928310ec481fc0909a4d44ef89f4241a)
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. */
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. */
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 
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 
76 struct vport *ovs_netdev_link(struct vport *vport, const char *name)
77 {
78 	int err;
79 
80 	vport->dev = dev_get_by_name(ovs_dp_get_net(vport->dp), name);
81 	/* Ensure that the device exists and that the provided
82 	 * name is not one of its aliases.
83 	 */
84 	if (!vport->dev || strcmp(name, ovs_vport_name(vport))) {
85 		err = -ENODEV;
86 		goto error_free_vport;
87 	}
88 	netdev_tracker_alloc(vport->dev, &vport->dev_tracker, GFP_KERNEL);
89 	if (vport->dev->flags & IFF_LOOPBACK ||
90 	    (vport->dev->type != ARPHRD_ETHER &&
91 	     vport->dev->type != ARPHRD_NONE) ||
92 	    ovs_is_internal_dev(vport->dev)) {
93 		err = -EINVAL;
94 		goto error_put;
95 	}
96 
97 	rtnl_lock();
98 	err = netdev_master_upper_dev_link(vport->dev,
99 					   get_dpdev(vport->dp),
100 					   NULL, NULL, NULL);
101 	if (err)
102 		goto error_unlock;
103 
104 	err = netdev_rx_handler_register(vport->dev, netdev_frame_hook,
105 					 vport);
106 	if (err)
107 		goto error_master_upper_dev_unlink;
108 
109 	dev_disable_lro(vport->dev);
110 	dev_set_promiscuity(vport->dev, 1);
111 	vport->dev->priv_flags |= IFF_OVS_DATAPATH;
112 	rtnl_unlock();
113 
114 	return vport;
115 
116 error_master_upper_dev_unlink:
117 	netdev_upper_dev_unlink(vport->dev, get_dpdev(vport->dp));
118 error_unlock:
119 	rtnl_unlock();
120 error_put:
121 	netdev_put(vport->dev, &vport->dev_tracker);
122 error_free_vport:
123 	ovs_vport_free(vport);
124 	return ERR_PTR(err);
125 }
126 EXPORT_SYMBOL_GPL(ovs_netdev_link);
127 
128 static struct vport *netdev_create(const struct vport_parms *parms)
129 {
130 	struct vport *vport;
131 
132 	vport = ovs_vport_alloc(0, &ovs_netdev_vport_ops, parms);
133 	if (IS_ERR(vport))
134 		return vport;
135 
136 	return ovs_netdev_link(vport, parms->name);
137 }
138 
139 static void vport_netdev_free(struct rcu_head *rcu)
140 {
141 	struct vport *vport = container_of(rcu, struct vport, rcu);
142 
143 	netdev_put(vport->dev, &vport->dev_tracker);
144 	ovs_vport_free(vport);
145 }
146 
147 void ovs_netdev_detach_dev(struct vport *vport)
148 {
149 	ASSERT_RTNL();
150 	vport->dev->priv_flags &= ~IFF_OVS_DATAPATH;
151 	netdev_rx_handler_unregister(vport->dev);
152 	netdev_upper_dev_unlink(vport->dev,
153 				netdev_master_upper_dev_get(vport->dev));
154 	dev_set_promiscuity(vport->dev, -1);
155 }
156 
157 static void netdev_destroy(struct vport *vport)
158 {
159 	rtnl_lock();
160 	if (netif_is_ovs_port(vport->dev))
161 		ovs_netdev_detach_dev(vport);
162 	rtnl_unlock();
163 
164 	call_rcu(&vport->rcu, vport_netdev_free);
165 }
166 
167 void ovs_netdev_tunnel_destroy(struct vport *vport)
168 {
169 	rtnl_lock();
170 	if (netif_is_ovs_port(vport->dev))
171 		ovs_netdev_detach_dev(vport);
172 
173 	/* We can be invoked by both explicit vport deletion and
174 	 * underlying netdev deregistration; delete the link only
175 	 * if it's not already shutting down.
176 	 */
177 	if (vport->dev->reg_state == NETREG_REGISTERED)
178 		rtnl_delete_link(vport->dev, 0, NULL);
179 	netdev_put(vport->dev, &vport->dev_tracker);
180 	vport->dev = NULL;
181 	rtnl_unlock();
182 
183 	call_rcu(&vport->rcu, vport_netdev_free);
184 }
185 EXPORT_SYMBOL_GPL(ovs_netdev_tunnel_destroy);
186 
187 /* Returns null if this device is not attached to a datapath. */
188 struct vport *ovs_netdev_get_vport(struct net_device *dev)
189 {
190 	if (likely(netif_is_ovs_port(dev)))
191 		return (struct vport *)
192 			rcu_dereference_rtnl(dev->rx_handler_data);
193 	else
194 		return NULL;
195 }
196 
197 static struct vport_ops ovs_netdev_vport_ops = {
198 	.type		= OVS_VPORT_TYPE_NETDEV,
199 	.create		= netdev_create,
200 	.destroy	= netdev_destroy,
201 	.send		= dev_queue_xmit,
202 };
203 
204 int __init ovs_netdev_init(void)
205 {
206 	return ovs_vport_ops_register(&ovs_netdev_vport_ops);
207 }
208 
209 void ovs_netdev_exit(void)
210 {
211 	ovs_vport_ops_unregister(&ovs_netdev_vport_ops);
212 }
213