1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30#include <linux/module.h>
31#include <linux/kernel.h>
32#include <linux/netdevice.h>
33#include <linux/etherdevice.h>
34#include <linux/init.h>
35#include <linux/moduleparam.h>
36#include <net/pkt_sched.h>
37#include <net/net_namespace.h>
38
39#define TX_TIMEOUT (2*HZ)
40
41#define TX_Q_LIMIT 32
42struct ifb_private {
43 struct tasklet_struct ifb_tasklet;
44 int tasklet_pending;
45
46 unsigned long st_task_enter;
47 unsigned long st_txq_refl_try;
48 unsigned long st_rxq_enter;
49 unsigned long st_rx2tx_tran;
50 unsigned long st_rxq_notenter;
51 unsigned long st_rx_frm_egr;
52 unsigned long st_rx_frm_ing;
53 unsigned long st_rxq_check;
54 unsigned long st_rxq_rsch;
55 struct sk_buff_head rq;
56 struct sk_buff_head tq;
57};
58
59static int numifbs = 2;
60
61static void ri_tasklet(unsigned long dev);
62static netdev_tx_t ifb_xmit(struct sk_buff *skb, struct net_device *dev);
63static int ifb_open(struct net_device *dev);
64static int ifb_close(struct net_device *dev);
65
66static void ri_tasklet(unsigned long dev)
67{
68
69 struct net_device *_dev = (struct net_device *)dev;
70 struct ifb_private *dp = netdev_priv(_dev);
71 struct net_device_stats *stats = &_dev->stats;
72 struct netdev_queue *txq;
73 struct sk_buff *skb;
74
75 txq = netdev_get_tx_queue(_dev, 0);
76 dp->st_task_enter++;
77 if ((skb = skb_peek(&dp->tq)) == NULL) {
78 dp->st_txq_refl_try++;
79 if (__netif_tx_trylock(txq)) {
80 dp->st_rxq_enter++;
81 while ((skb = skb_dequeue(&dp->rq)) != NULL) {
82 skb_queue_tail(&dp->tq, skb);
83 dp->st_rx2tx_tran++;
84 }
85 __netif_tx_unlock(txq);
86 } else {
87
88 dp->st_rxq_notenter++;
89 goto resched;
90 }
91 }
92
93 while ((skb = skb_dequeue(&dp->tq)) != NULL) {
94 u32 from = G_TC_FROM(skb->tc_verd);
95
96 skb->tc_verd = 0;
97 skb->tc_verd = SET_TC_NCLS(skb->tc_verd);
98 stats->tx_packets++;
99 stats->tx_bytes +=skb->len;
100
101 skb->dev = dev_get_by_index(&init_net, skb->iif);
102 if (!skb->dev) {
103 dev_kfree_skb(skb);
104 stats->tx_dropped++;
105 break;
106 }
107 dev_put(skb->dev);
108 skb->iif = _dev->ifindex;
109
110 if (from & AT_EGRESS) {
111 dp->st_rx_frm_egr++;
112 dev_queue_xmit(skb);
113 } else if (from & AT_INGRESS) {
114 dp->st_rx_frm_ing++;
115 skb_pull(skb, skb->dev->hard_header_len);
116 netif_rx(skb);
117 } else
118 BUG();
119 }
120
121 if (__netif_tx_trylock(txq)) {
122 dp->st_rxq_check++;
123 if ((skb = skb_peek(&dp->rq)) == NULL) {
124 dp->tasklet_pending = 0;
125 if (netif_queue_stopped(_dev))
126 netif_wake_queue(_dev);
127 } else {
128 dp->st_rxq_rsch++;
129 __netif_tx_unlock(txq);
130 goto resched;
131 }
132 __netif_tx_unlock(txq);
133 } else {
134resched:
135 dp->tasklet_pending = 1;
136 tasklet_schedule(&dp->ifb_tasklet);
137 }
138
139}
140
141static const struct net_device_ops ifb_netdev_ops = {
142 .ndo_open = ifb_open,
143 .ndo_stop = ifb_close,
144 .ndo_start_xmit = ifb_xmit,
145 .ndo_validate_addr = eth_validate_addr,
146};
147
148static void ifb_setup(struct net_device *dev)
149{
150
151 dev->destructor = free_netdev;
152 dev->netdev_ops = &ifb_netdev_ops;
153
154
155 ether_setup(dev);
156 dev->tx_queue_len = TX_Q_LIMIT;
157
158 dev->flags |= IFF_NOARP;
159 dev->flags &= ~IFF_MULTICAST;
160 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
161 random_ether_addr(dev->dev_addr);
162}
163
164static netdev_tx_t ifb_xmit(struct sk_buff *skb, struct net_device *dev)
165{
166 struct ifb_private *dp = netdev_priv(dev);
167 struct net_device_stats *stats = &dev->stats;
168 u32 from = G_TC_FROM(skb->tc_verd);
169
170 stats->rx_packets++;
171 stats->rx_bytes+=skb->len;
172
173 if (!(from & (AT_INGRESS|AT_EGRESS)) || !skb->iif) {
174 dev_kfree_skb(skb);
175 stats->rx_dropped++;
176 return NETDEV_TX_OK;
177 }
178
179 if (skb_queue_len(&dp->rq) >= dev->tx_queue_len) {
180 netif_stop_queue(dev);
181 }
182
183 dev->trans_start = jiffies;
184 skb_queue_tail(&dp->rq, skb);
185 if (!dp->tasklet_pending) {
186 dp->tasklet_pending = 1;
187 tasklet_schedule(&dp->ifb_tasklet);
188 }
189
190 return NETDEV_TX_OK;
191}
192
193static int ifb_close(struct net_device *dev)
194{
195 struct ifb_private *dp = netdev_priv(dev);
196
197 tasklet_kill(&dp->ifb_tasklet);
198 netif_stop_queue(dev);
199 skb_queue_purge(&dp->rq);
200 skb_queue_purge(&dp->tq);
201 return 0;
202}
203
204static int ifb_open(struct net_device *dev)
205{
206 struct ifb_private *dp = netdev_priv(dev);
207
208 tasklet_init(&dp->ifb_tasklet, ri_tasklet, (unsigned long)dev);
209 skb_queue_head_init(&dp->rq);
210 skb_queue_head_init(&dp->tq);
211 netif_start_queue(dev);
212
213 return 0;
214}
215
216static int ifb_validate(struct nlattr *tb[], struct nlattr *data[])
217{
218 if (tb[IFLA_ADDRESS]) {
219 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
220 return -EINVAL;
221 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
222 return -EADDRNOTAVAIL;
223 }
224 return 0;
225}
226
227static struct rtnl_link_ops ifb_link_ops __read_mostly = {
228 .kind = "ifb",
229 .priv_size = sizeof(struct ifb_private),
230 .setup = ifb_setup,
231 .validate = ifb_validate,
232};
233
234
235module_param(numifbs, int, 0);
236MODULE_PARM_DESC(numifbs, "Number of ifb devices");
237
238static int __init ifb_init_one(int index)
239{
240 struct net_device *dev_ifb;
241 int err;
242
243 dev_ifb = alloc_netdev(sizeof(struct ifb_private),
244 "ifb%d", ifb_setup);
245
246 if (!dev_ifb)
247 return -ENOMEM;
248
249 err = dev_alloc_name(dev_ifb, dev_ifb->name);
250 if (err < 0)
251 goto err;
252
253 dev_ifb->rtnl_link_ops = &ifb_link_ops;
254 err = register_netdevice(dev_ifb);
255 if (err < 0)
256 goto err;
257
258 return 0;
259
260err:
261 free_netdev(dev_ifb);
262 return err;
263}
264
265static int __init ifb_init_module(void)
266{
267 int i, err;
268
269 rtnl_lock();
270 err = __rtnl_link_register(&ifb_link_ops);
271
272 for (i = 0; i < numifbs && !err; i++)
273 err = ifb_init_one(i);
274 if (err)
275 __rtnl_link_unregister(&ifb_link_ops);
276 rtnl_unlock();
277
278 return err;
279}
280
281static void __exit ifb_cleanup_module(void)
282{
283 rtnl_link_unregister(&ifb_link_ops);
284}
285
286module_init(ifb_init_module);
287module_exit(ifb_cleanup_module);
288MODULE_LICENSE("GPL");
289MODULE_AUTHOR("Jamal Hadi Salim");
290MODULE_ALIAS_RTNL_LINK("ifb");
291
