1 /*
2 * Copyright (c) 2007-2011 Nicira Networks.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of version 2 of the GNU General Public
6 * License as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public License
14 * along with this program; if not, write to the Free Software
15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
16 * 02110-1301, USA
17 */
18
19 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
20
21 #include <linux/if_arp.h>
22 #include <linux/if_bridge.h>
23 #include <linux/if_vlan.h>
24 #include <linux/kernel.h>
25 #include <linux/llc.h>
26 #include <linux/rtnetlink.h>
27 #include <linux/skbuff.h>
28
29 #include <net/llc.h>
30
31 #include "datapath.h"
32 #include "vport-internal_dev.h"
33 #include "vport-netdev.h"
34
35 /* Must be called with rcu_read_lock. */
netdev_port_receive(struct vport * vport,struct sk_buff * skb)36 static void netdev_port_receive(struct vport *vport, struct sk_buff *skb)
37 {
38 if (unlikely(!vport)) {
39 kfree_skb(skb);
40 return;
41 }
42
43 /* Make our own copy of the packet. Otherwise we will mangle the
44 * packet for anyone who came before us (e.g. tcpdump via AF_PACKET).
45 * (No one comes after us, since we tell handle_bridge() that we took
46 * the packet.) */
47 skb = skb_share_check(skb, GFP_ATOMIC);
48 if (unlikely(!skb))
49 return;
50
51 skb_push(skb, ETH_HLEN);
52 ovs_vport_receive(vport, skb);
53 }
54
55 /* Called with rcu_read_lock and bottom-halves disabled. */
netdev_frame_hook(struct sk_buff ** pskb)56 static rx_handler_result_t netdev_frame_hook(struct sk_buff **pskb)
57 {
58 struct sk_buff *skb = *pskb;
59 struct vport *vport;
60
61 if (unlikely(skb->pkt_type == PACKET_LOOPBACK))
62 return RX_HANDLER_PASS;
63
64 vport = ovs_netdev_get_vport(skb->dev);
65
66 netdev_port_receive(vport, skb);
67
68 return RX_HANDLER_CONSUMED;
69 }
70
netdev_create(const struct vport_parms * parms)71 static struct vport *netdev_create(const struct vport_parms *parms)
72 {
73 struct vport *vport;
74 struct netdev_vport *netdev_vport;
75 int err;
76
77 vport = ovs_vport_alloc(sizeof(struct netdev_vport),
78 &ovs_netdev_vport_ops, parms);
79 if (IS_ERR(vport)) {
80 err = PTR_ERR(vport);
81 goto error;
82 }
83
84 netdev_vport = netdev_vport_priv(vport);
85
86 netdev_vport->dev = dev_get_by_name(&init_net, parms->name);
87 if (!netdev_vport->dev) {
88 err = -ENODEV;
89 goto error_free_vport;
90 }
91
92 if (netdev_vport->dev->flags & IFF_LOOPBACK ||
93 netdev_vport->dev->type != ARPHRD_ETHER ||
94 ovs_is_internal_dev(netdev_vport->dev)) {
95 err = -EINVAL;
96 goto error_put;
97 }
98
99 err = netdev_rx_handler_register(netdev_vport->dev, netdev_frame_hook,
100 vport);
101 if (err)
102 goto error_put;
103
104 dev_set_promiscuity(netdev_vport->dev, 1);
105 netdev_vport->dev->priv_flags |= IFF_OVS_DATAPATH;
106
107 return vport;
108
109 error_put:
110 dev_put(netdev_vport->dev);
111 error_free_vport:
112 ovs_vport_free(vport);
113 error:
114 return ERR_PTR(err);
115 }
116
netdev_destroy(struct vport * vport)117 static void netdev_destroy(struct vport *vport)
118 {
119 struct netdev_vport *netdev_vport = netdev_vport_priv(vport);
120
121 netdev_vport->dev->priv_flags &= ~IFF_OVS_DATAPATH;
122 netdev_rx_handler_unregister(netdev_vport->dev);
123 dev_set_promiscuity(netdev_vport->dev, -1);
124
125 synchronize_rcu();
126
127 dev_put(netdev_vport->dev);
128 ovs_vport_free(vport);
129 }
130
ovs_netdev_get_name(const struct vport * vport)131 const char *ovs_netdev_get_name(const struct vport *vport)
132 {
133 const struct netdev_vport *netdev_vport = netdev_vport_priv(vport);
134 return netdev_vport->dev->name;
135 }
136
ovs_netdev_get_ifindex(const struct vport * vport)137 int ovs_netdev_get_ifindex(const struct vport *vport)
138 {
139 const struct netdev_vport *netdev_vport = netdev_vport_priv(vport);
140 return netdev_vport->dev->ifindex;
141 }
142
packet_length(const struct sk_buff * skb)143 static unsigned packet_length(const struct sk_buff *skb)
144 {
145 unsigned length = skb->len - ETH_HLEN;
146
147 if (skb->protocol == htons(ETH_P_8021Q))
148 length -= VLAN_HLEN;
149
150 return length;
151 }
152
netdev_send(struct vport * vport,struct sk_buff * skb)153 static int netdev_send(struct vport *vport, struct sk_buff *skb)
154 {
155 struct netdev_vport *netdev_vport = netdev_vport_priv(vport);
156 int mtu = netdev_vport->dev->mtu;
157 int len;
158
159 if (unlikely(packet_length(skb) > mtu && !skb_is_gso(skb))) {
160 if (net_ratelimit())
161 pr_warn("%s: dropped over-mtu packet: %d > %d\n",
162 ovs_dp_name(vport->dp), packet_length(skb), mtu);
163 goto error;
164 }
165
166 if (unlikely(skb_warn_if_lro(skb)))
167 goto error;
168
169 skb->dev = netdev_vport->dev;
170 len = skb->len;
171 dev_queue_xmit(skb);
172
173 return len;
174
175 error:
176 kfree_skb(skb);
177 ovs_vport_record_error(vport, VPORT_E_TX_DROPPED);
178 return 0;
179 }
180
181 /* Returns null if this device is not attached to a datapath. */
ovs_netdev_get_vport(struct net_device * dev)182 struct vport *ovs_netdev_get_vport(struct net_device *dev)
183 {
184 if (likely(dev->priv_flags & IFF_OVS_DATAPATH))
185 return (struct vport *)
186 rcu_dereference_rtnl(dev->rx_handler_data);
187 else
188 return NULL;
189 }
190
191 const struct vport_ops ovs_netdev_vport_ops = {
192 .type = OVS_VPORT_TYPE_NETDEV,
193 .create = netdev_create,
194 .destroy = netdev_destroy,
195 .get_name = ovs_netdev_get_name,
196 .get_ifindex = ovs_netdev_get_ifindex,
197 .send = netdev_send,
198 };
199