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1// SPDX-License-Identifier: GPL-2.0-or-later
2/* drivers/net/ifb.c:
3
4 The purpose of this driver is to provide a device that allows
5 for sharing of resources:
6
7 1) qdiscs/policies that are per device as opposed to system wide.
8 ifb allows for a device which can be redirected to thus providing
9 an impression of sharing.
10
11 2) Allows for queueing incoming traffic for shaping instead of
12 dropping.
13
14 The original concept is based on what is known as the IMQ
15 driver initially written by Martin Devera, later rewritten
16 by Patrick McHardy and then maintained by Andre Correa.
17
18 You need the tc action mirror or redirect to feed this device
19 packets.
20
21
22 Authors: Jamal Hadi Salim (2005)
23
24*/
25
26
27#include <linux/module.h>
28#include <linux/kernel.h>
29#include <linux/netdevice.h>
30#include <linux/ethtool.h>
31#include <linux/etherdevice.h>
32#include <linux/init.h>
33#include <linux/interrupt.h>
34#include <linux/moduleparam.h>
35#include <linux/netfilter_netdev.h>
36#include <net/pkt_sched.h>
37#include <net/net_namespace.h>
38
39#define TX_Q_LIMIT 32
40
41struct ifb_q_stats {
42 u64 packets;
43 u64 bytes;
44 struct u64_stats_sync sync;
45};
46
47struct ifb_q_private {
48 struct net_device *dev;
49 struct tasklet_struct ifb_tasklet;
50 int tasklet_pending;
51 int txqnum;
52 struct sk_buff_head rq;
53 struct sk_buff_head tq;
54 struct ifb_q_stats rx_stats;
55 struct ifb_q_stats tx_stats;
56} ____cacheline_aligned_in_smp;
57
58struct ifb_dev_private {
59 struct ifb_q_private *tx_private;
60};
61
62/* For ethtools stats. */
63struct ifb_q_stats_desc {
64 char desc[ETH_GSTRING_LEN];
65 size_t offset;
66};
67
68#define IFB_Q_STAT(m) offsetof(struct ifb_q_stats, m)
69
70static const struct ifb_q_stats_desc ifb_q_stats_desc[] = {
71 { "packets", IFB_Q_STAT(packets) },
72 { "bytes", IFB_Q_STAT(bytes) },
73};
74
75#define IFB_Q_STATS_LEN ARRAY_SIZE(ifb_q_stats_desc)
76
77static netdev_tx_t ifb_xmit(struct sk_buff *skb, struct net_device *dev);
78static int ifb_open(struct net_device *dev);
79static int ifb_close(struct net_device *dev);
80
81static void ifb_update_q_stats(struct ifb_q_stats *stats, int len)
82{
83 u64_stats_update_begin(&stats->sync);
84 stats->packets++;
85 stats->bytes += len;
86 u64_stats_update_end(&stats->sync);
87}
88
89static void ifb_ri_tasklet(struct tasklet_struct *t)
90{
91 struct ifb_q_private *txp = from_tasklet(txp, t, ifb_tasklet);
92 struct netdev_queue *txq;
93 struct sk_buff *skb;
94
95 txq = netdev_get_tx_queue(txp->dev, txp->txqnum);
96 skb = skb_peek(&txp->tq);
97 if (!skb) {
98 if (!__netif_tx_trylock(txq))
99 goto resched;
100 skb_queue_splice_tail_init(&txp->rq, &txp->tq);
101 __netif_tx_unlock(txq);
102 }
103
104 while ((skb = __skb_dequeue(&txp->tq)) != NULL) {
105 /* Skip tc and netfilter to prevent redirection loop. */
106 skb->redirected = 0;
107#ifdef CONFIG_NET_CLS_ACT
108 skb->tc_skip_classify = 1;
109#endif
110 nf_skip_egress(skb, true);
111
112 ifb_update_q_stats(&txp->tx_stats, skb->len);
113
114 rcu_read_lock();
115 skb->dev = dev_get_by_index_rcu(dev_net(txp->dev), skb->skb_iif);
116 if (!skb->dev) {
117 rcu_read_unlock();
118 dev_kfree_skb(skb);
119 txp->dev->stats.tx_dropped++;
120 if (skb_queue_len(&txp->tq) != 0)
121 goto resched;
122 break;
123 }
124 rcu_read_unlock();
125 skb->skb_iif = txp->dev->ifindex;
126
127 if (!skb->from_ingress) {
128 dev_queue_xmit(skb);
129 } else {
130 skb_pull_rcsum(skb, skb->mac_len);
131 netif_receive_skb(skb);
132 }
133 }
134
135 if (__netif_tx_trylock(txq)) {
136 skb = skb_peek(&txp->rq);
137 if (!skb) {
138 txp->tasklet_pending = 0;
139 if (netif_tx_queue_stopped(txq))
140 netif_tx_wake_queue(txq);
141 } else {
142 __netif_tx_unlock(txq);
143 goto resched;
144 }
145 __netif_tx_unlock(txq);
146 } else {
147resched:
148 txp->tasklet_pending = 1;
149 tasklet_schedule(&txp->ifb_tasklet);
150 }
151
152}
153
154static void ifb_stats64(struct net_device *dev,
155 struct rtnl_link_stats64 *stats)
156{
157 struct ifb_dev_private *dp = netdev_priv(dev);
158 struct ifb_q_private *txp = dp->tx_private;
159 unsigned int start;
160 u64 packets, bytes;
161 int i;
162
163 for (i = 0; i < dev->num_tx_queues; i++,txp++) {
164 do {
165 start = u64_stats_fetch_begin(&txp->rx_stats.sync);
166 packets = txp->rx_stats.packets;
167 bytes = txp->rx_stats.bytes;
168 } while (u64_stats_fetch_retry(&txp->rx_stats.sync, start));
169 stats->rx_packets += packets;
170 stats->rx_bytes += bytes;
171
172 do {
173 start = u64_stats_fetch_begin(&txp->tx_stats.sync);
174 packets = txp->tx_stats.packets;
175 bytes = txp->tx_stats.bytes;
176 } while (u64_stats_fetch_retry(&txp->tx_stats.sync, start));
177 stats->tx_packets += packets;
178 stats->tx_bytes += bytes;
179 }
180 stats->rx_dropped = dev->stats.rx_dropped;
181 stats->tx_dropped = dev->stats.tx_dropped;
182}
183
184static int ifb_dev_init(struct net_device *dev)
185{
186 struct ifb_dev_private *dp = netdev_priv(dev);
187 struct ifb_q_private *txp;
188 int i;
189
190 txp = kcalloc(dev->num_tx_queues, sizeof(*txp), GFP_KERNEL);
191 if (!txp)
192 return -ENOMEM;
193 dp->tx_private = txp;
194 for (i = 0; i < dev->num_tx_queues; i++,txp++) {
195 txp->txqnum = i;
196 txp->dev = dev;
197 __skb_queue_head_init(&txp->rq);
198 __skb_queue_head_init(&txp->tq);
199 u64_stats_init(&txp->rx_stats.sync);
200 u64_stats_init(&txp->tx_stats.sync);
201 tasklet_setup(&txp->ifb_tasklet, ifb_ri_tasklet);
202 netif_tx_start_queue(netdev_get_tx_queue(dev, i));
203 }
204 return 0;
205}
206
207static void ifb_get_strings(struct net_device *dev, u32 stringset, u8 *buf)
208{
209 u8 *p = buf;
210 int i, j;
211
212 switch (stringset) {
213 case ETH_SS_STATS:
214 for (i = 0; i < dev->real_num_rx_queues; i++)
215 for (j = 0; j < IFB_Q_STATS_LEN; j++)
216 ethtool_sprintf(&p, "rx_queue_%u_%.18s",
217 i, ifb_q_stats_desc[j].desc);
218
219 for (i = 0; i < dev->real_num_tx_queues; i++)
220 for (j = 0; j < IFB_Q_STATS_LEN; j++)
221 ethtool_sprintf(&p, "tx_queue_%u_%.18s",
222 i, ifb_q_stats_desc[j].desc);
223
224 break;
225 }
226}
227
228static int ifb_get_sset_count(struct net_device *dev, int sset)
229{
230 switch (sset) {
231 case ETH_SS_STATS:
232 return IFB_Q_STATS_LEN * (dev->real_num_rx_queues +
233 dev->real_num_tx_queues);
234 default:
235 return -EOPNOTSUPP;
236 }
237}
238
239static void ifb_fill_stats_data(u64 **data,
240 struct ifb_q_stats *q_stats)
241{
242 void *stats_base = (void *)q_stats;
243 unsigned int start;
244 size_t offset;
245 int j;
246
247 do {
248 start = u64_stats_fetch_begin(&q_stats->sync);
249 for (j = 0; j < IFB_Q_STATS_LEN; j++) {
250 offset = ifb_q_stats_desc[j].offset;
251 (*data)[j] = *(u64 *)(stats_base + offset);
252 }
253 } while (u64_stats_fetch_retry(&q_stats->sync, start));
254
255 *data += IFB_Q_STATS_LEN;
256}
257
258static void ifb_get_ethtool_stats(struct net_device *dev,
259 struct ethtool_stats *stats, u64 *data)
260{
261 struct ifb_dev_private *dp = netdev_priv(dev);
262 struct ifb_q_private *txp;
263 int i;
264
265 for (i = 0; i < dev->real_num_rx_queues; i++) {
266 txp = dp->tx_private + i;
267 ifb_fill_stats_data(&data, &txp->rx_stats);
268 }
269
270 for (i = 0; i < dev->real_num_tx_queues; i++) {
271 txp = dp->tx_private + i;
272 ifb_fill_stats_data(&data, &txp->tx_stats);
273 }
274}
275
276static const struct net_device_ops ifb_netdev_ops = {
277 .ndo_open = ifb_open,
278 .ndo_stop = ifb_close,
279 .ndo_get_stats64 = ifb_stats64,
280 .ndo_start_xmit = ifb_xmit,
281 .ndo_validate_addr = eth_validate_addr,
282 .ndo_init = ifb_dev_init,
283};
284
285static const struct ethtool_ops ifb_ethtool_ops = {
286 .get_strings = ifb_get_strings,
287 .get_sset_count = ifb_get_sset_count,
288 .get_ethtool_stats = ifb_get_ethtool_stats,
289};
290
291#define IFB_FEATURES (NETIF_F_HW_CSUM | NETIF_F_SG | NETIF_F_FRAGLIST | \
292 NETIF_F_GSO_SOFTWARE | NETIF_F_GSO_ENCAP_ALL | \
293 NETIF_F_HIGHDMA | NETIF_F_HW_VLAN_CTAG_TX | \
294 NETIF_F_HW_VLAN_STAG_TX)
295
296static void ifb_dev_free(struct net_device *dev)
297{
298 struct ifb_dev_private *dp = netdev_priv(dev);
299 struct ifb_q_private *txp = dp->tx_private;
300 int i;
301
302 for (i = 0; i < dev->num_tx_queues; i++,txp++) {
303 tasklet_kill(&txp->ifb_tasklet);
304 __skb_queue_purge(&txp->rq);
305 __skb_queue_purge(&txp->tq);
306 }
307 kfree(dp->tx_private);
308}
309
310static void ifb_setup(struct net_device *dev)
311{
312 /* Initialize the device structure. */
313 dev->netdev_ops = &ifb_netdev_ops;
314 dev->ethtool_ops = &ifb_ethtool_ops;
315
316 /* Fill in device structure with ethernet-generic values. */
317 ether_setup(dev);
318 dev->tx_queue_len = TX_Q_LIMIT;
319
320 dev->features |= IFB_FEATURES;
321 dev->hw_features |= dev->features;
322 dev->hw_enc_features |= dev->features;
323 dev->vlan_features |= IFB_FEATURES & ~(NETIF_F_HW_VLAN_CTAG_TX |
324 NETIF_F_HW_VLAN_STAG_TX);
325
326 dev->flags |= IFF_NOARP;
327 dev->flags &= ~IFF_MULTICAST;
328 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
329 netif_keep_dst(dev);
330 eth_hw_addr_random(dev);
331 dev->needs_free_netdev = true;
332 dev->priv_destructor = ifb_dev_free;
333
334 dev->min_mtu = 0;
335 dev->max_mtu = 0;
336}
337
338static netdev_tx_t ifb_xmit(struct sk_buff *skb, struct net_device *dev)
339{
340 struct ifb_dev_private *dp = netdev_priv(dev);
341 struct ifb_q_private *txp = dp->tx_private + skb_get_queue_mapping(skb);
342
343 ifb_update_q_stats(&txp->rx_stats, skb->len);
344
345 if (!skb->redirected || !skb->skb_iif) {
346 dev_kfree_skb(skb);
347 dev->stats.rx_dropped++;
348 return NETDEV_TX_OK;
349 }
350
351 if (skb_queue_len(&txp->rq) >= dev->tx_queue_len)
352 netif_tx_stop_queue(netdev_get_tx_queue(dev, txp->txqnum));
353
354 __skb_queue_tail(&txp->rq, skb);
355 if (!txp->tasklet_pending) {
356 txp->tasklet_pending = 1;
357 tasklet_schedule(&txp->ifb_tasklet);
358 }
359
360 return NETDEV_TX_OK;
361}
362
363static int ifb_close(struct net_device *dev)
364{
365 netif_tx_stop_all_queues(dev);
366 return 0;
367}
368
369static int ifb_open(struct net_device *dev)
370{
371 netif_tx_start_all_queues(dev);
372 return 0;
373}
374
375static int ifb_validate(struct nlattr *tb[], struct nlattr *data[],
376 struct netlink_ext_ack *extack)
377{
378 if (tb[IFLA_ADDRESS]) {
379 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
380 return -EINVAL;
381 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
382 return -EADDRNOTAVAIL;
383 }
384 return 0;
385}
386
387static struct rtnl_link_ops ifb_link_ops __read_mostly = {
388 .kind = "ifb",
389 .priv_size = sizeof(struct ifb_dev_private),
390 .setup = ifb_setup,
391 .validate = ifb_validate,
392};
393
394/* Number of ifb devices to be set up by this module.
395 * Note that these legacy devices have one queue.
396 * Prefer something like : ip link add ifb10 numtxqueues 8 type ifb
397 */
398static int numifbs = 2;
399module_param(numifbs, int, 0);
400MODULE_PARM_DESC(numifbs, "Number of ifb devices");
401
402static int __init ifb_init_one(int index)
403{
404 struct net_device *dev_ifb;
405 int err;
406
407 dev_ifb = alloc_netdev(sizeof(struct ifb_dev_private), "ifb%d",
408 NET_NAME_UNKNOWN, ifb_setup);
409
410 if (!dev_ifb)
411 return -ENOMEM;
412
413 dev_ifb->rtnl_link_ops = &ifb_link_ops;
414 err = register_netdevice(dev_ifb);
415 if (err < 0)
416 goto err;
417
418 return 0;
419
420err:
421 free_netdev(dev_ifb);
422 return err;
423}
424
425static int __init ifb_init_module(void)
426{
427 int i, err;
428
429 down_write(&pernet_ops_rwsem);
430 rtnl_lock();
431 err = __rtnl_link_register(&ifb_link_ops);
432 if (err < 0)
433 goto out;
434
435 for (i = 0; i < numifbs && !err; i++) {
436 err = ifb_init_one(i);
437 cond_resched();
438 }
439 if (err)
440 __rtnl_link_unregister(&ifb_link_ops);
441
442out:
443 rtnl_unlock();
444 up_write(&pernet_ops_rwsem);
445
446 return err;
447}
448
449static void __exit ifb_cleanup_module(void)
450{
451 rtnl_link_unregister(&ifb_link_ops);
452}
453
454module_init(ifb_init_module);
455module_exit(ifb_cleanup_module);
456MODULE_LICENSE("GPL");
457MODULE_DESCRIPTION("Intermediate Functional Block (ifb) netdevice driver for sharing of resources and ingress packet queuing");
458MODULE_AUTHOR("Jamal Hadi Salim");
459MODULE_ALIAS_RTNL_LINK("ifb");
1/* drivers/net/ifb.c:
2
3 The purpose of this driver is to provide a device that allows
4 for sharing of resources:
5
6 1) qdiscs/policies that are per device as opposed to system wide.
7 ifb allows for a device which can be redirected to thus providing
8 an impression of sharing.
9
10 2) Allows for queueing incoming traffic for shaping instead of
11 dropping.
12
13 The original concept is based on what is known as the IMQ
14 driver initially written by Martin Devera, later rewritten
15 by Patrick McHardy and then maintained by Andre Correa.
16
17 You need the tc action mirror or redirect to feed this device
18 packets.
19
20 This program is free software; you can redistribute it and/or
21 modify it under the terms of the GNU General Public License
22 as published by the Free Software Foundation; either version
23 2 of the License, or (at your option) any later version.
24
25 Authors: Jamal Hadi Salim (2005)
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/interrupt.h>
36#include <linux/moduleparam.h>
37#include <net/pkt_sched.h>
38#include <net/net_namespace.h>
39
40#define TX_Q_LIMIT 32
41struct ifb_private {
42 struct tasklet_struct ifb_tasklet;
43 int tasklet_pending;
44
45 struct u64_stats_sync rsync;
46 struct sk_buff_head rq;
47 u64 rx_packets;
48 u64 rx_bytes;
49
50 struct u64_stats_sync tsync;
51 struct sk_buff_head tq;
52 u64 tx_packets;
53 u64 tx_bytes;
54};
55
56static int numifbs = 2;
57
58static void ri_tasklet(unsigned long dev);
59static netdev_tx_t ifb_xmit(struct sk_buff *skb, struct net_device *dev);
60static int ifb_open(struct net_device *dev);
61static int ifb_close(struct net_device *dev);
62
63static void ri_tasklet(unsigned long dev)
64{
65 struct net_device *_dev = (struct net_device *)dev;
66 struct ifb_private *dp = netdev_priv(_dev);
67 struct netdev_queue *txq;
68 struct sk_buff *skb;
69
70 txq = netdev_get_tx_queue(_dev, 0);
71 if ((skb = skb_peek(&dp->tq)) == NULL) {
72 if (__netif_tx_trylock(txq)) {
73 skb_queue_splice_tail_init(&dp->rq, &dp->tq);
74 __netif_tx_unlock(txq);
75 } else {
76 /* reschedule */
77 goto resched;
78 }
79 }
80
81 while ((skb = __skb_dequeue(&dp->tq)) != NULL) {
82 u32 from = G_TC_FROM(skb->tc_verd);
83
84 skb->tc_verd = 0;
85 skb->tc_verd = SET_TC_NCLS(skb->tc_verd);
86
87 u64_stats_update_begin(&dp->tsync);
88 dp->tx_packets++;
89 dp->tx_bytes += skb->len;
90 u64_stats_update_end(&dp->tsync);
91
92 rcu_read_lock();
93 skb->dev = dev_get_by_index_rcu(&init_net, skb->skb_iif);
94 if (!skb->dev) {
95 rcu_read_unlock();
96 dev_kfree_skb(skb);
97 _dev->stats.tx_dropped++;
98 if (skb_queue_len(&dp->tq) != 0)
99 goto resched;
100 break;
101 }
102 rcu_read_unlock();
103 skb->skb_iif = _dev->ifindex;
104
105 if (from & AT_EGRESS) {
106 dev_queue_xmit(skb);
107 } else if (from & AT_INGRESS) {
108 skb_pull(skb, skb->dev->hard_header_len);
109 netif_receive_skb(skb);
110 } else
111 BUG();
112 }
113
114 if (__netif_tx_trylock(txq)) {
115 if ((skb = skb_peek(&dp->rq)) == NULL) {
116 dp->tasklet_pending = 0;
117 if (netif_queue_stopped(_dev))
118 netif_wake_queue(_dev);
119 } else {
120 __netif_tx_unlock(txq);
121 goto resched;
122 }
123 __netif_tx_unlock(txq);
124 } else {
125resched:
126 dp->tasklet_pending = 1;
127 tasklet_schedule(&dp->ifb_tasklet);
128 }
129
130}
131
132static struct rtnl_link_stats64 *ifb_stats64(struct net_device *dev,
133 struct rtnl_link_stats64 *stats)
134{
135 struct ifb_private *dp = netdev_priv(dev);
136 unsigned int start;
137
138 do {
139 start = u64_stats_fetch_begin_bh(&dp->rsync);
140 stats->rx_packets = dp->rx_packets;
141 stats->rx_bytes = dp->rx_bytes;
142 } while (u64_stats_fetch_retry_bh(&dp->rsync, start));
143
144 do {
145 start = u64_stats_fetch_begin_bh(&dp->tsync);
146
147 stats->tx_packets = dp->tx_packets;
148 stats->tx_bytes = dp->tx_bytes;
149
150 } while (u64_stats_fetch_retry_bh(&dp->tsync, start));
151
152 stats->rx_dropped = dev->stats.rx_dropped;
153 stats->tx_dropped = dev->stats.tx_dropped;
154
155 return stats;
156}
157
158
159static const struct net_device_ops ifb_netdev_ops = {
160 .ndo_open = ifb_open,
161 .ndo_stop = ifb_close,
162 .ndo_get_stats64 = ifb_stats64,
163 .ndo_start_xmit = ifb_xmit,
164 .ndo_validate_addr = eth_validate_addr,
165};
166
167#define IFB_FEATURES (NETIF_F_NO_CSUM | NETIF_F_SG | NETIF_F_FRAGLIST | \
168 NETIF_F_TSO_ECN | NETIF_F_TSO | NETIF_F_TSO6 | \
169 NETIF_F_HIGHDMA | NETIF_F_HW_VLAN_TX)
170
171static void ifb_setup(struct net_device *dev)
172{
173 /* Initialize the device structure. */
174 dev->destructor = free_netdev;
175 dev->netdev_ops = &ifb_netdev_ops;
176
177 /* Fill in device structure with ethernet-generic values. */
178 ether_setup(dev);
179 dev->tx_queue_len = TX_Q_LIMIT;
180
181 dev->features |= IFB_FEATURES;
182 dev->vlan_features |= IFB_FEATURES;
183
184 dev->flags |= IFF_NOARP;
185 dev->flags &= ~IFF_MULTICAST;
186 dev->priv_flags &= ~(IFF_XMIT_DST_RELEASE | IFF_TX_SKB_SHARING);
187 random_ether_addr(dev->dev_addr);
188}
189
190static netdev_tx_t ifb_xmit(struct sk_buff *skb, struct net_device *dev)
191{
192 struct ifb_private *dp = netdev_priv(dev);
193 u32 from = G_TC_FROM(skb->tc_verd);
194
195 u64_stats_update_begin(&dp->rsync);
196 dp->rx_packets++;
197 dp->rx_bytes += skb->len;
198 u64_stats_update_end(&dp->rsync);
199
200 if (!(from & (AT_INGRESS|AT_EGRESS)) || !skb->skb_iif) {
201 dev_kfree_skb(skb);
202 dev->stats.rx_dropped++;
203 return NETDEV_TX_OK;
204 }
205
206 if (skb_queue_len(&dp->rq) >= dev->tx_queue_len) {
207 netif_stop_queue(dev);
208 }
209
210 __skb_queue_tail(&dp->rq, skb);
211 if (!dp->tasklet_pending) {
212 dp->tasklet_pending = 1;
213 tasklet_schedule(&dp->ifb_tasklet);
214 }
215
216 return NETDEV_TX_OK;
217}
218
219static int ifb_close(struct net_device *dev)
220{
221 struct ifb_private *dp = netdev_priv(dev);
222
223 tasklet_kill(&dp->ifb_tasklet);
224 netif_stop_queue(dev);
225 __skb_queue_purge(&dp->rq);
226 __skb_queue_purge(&dp->tq);
227 return 0;
228}
229
230static int ifb_open(struct net_device *dev)
231{
232 struct ifb_private *dp = netdev_priv(dev);
233
234 tasklet_init(&dp->ifb_tasklet, ri_tasklet, (unsigned long)dev);
235 __skb_queue_head_init(&dp->rq);
236 __skb_queue_head_init(&dp->tq);
237 netif_start_queue(dev);
238
239 return 0;
240}
241
242static int ifb_validate(struct nlattr *tb[], struct nlattr *data[])
243{
244 if (tb[IFLA_ADDRESS]) {
245 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
246 return -EINVAL;
247 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
248 return -EADDRNOTAVAIL;
249 }
250 return 0;
251}
252
253static struct rtnl_link_ops ifb_link_ops __read_mostly = {
254 .kind = "ifb",
255 .priv_size = sizeof(struct ifb_private),
256 .setup = ifb_setup,
257 .validate = ifb_validate,
258};
259
260/* Number of ifb devices to be set up by this module. */
261module_param(numifbs, int, 0);
262MODULE_PARM_DESC(numifbs, "Number of ifb devices");
263
264static int __init ifb_init_one(int index)
265{
266 struct net_device *dev_ifb;
267 int err;
268
269 dev_ifb = alloc_netdev(sizeof(struct ifb_private),
270 "ifb%d", ifb_setup);
271
272 if (!dev_ifb)
273 return -ENOMEM;
274
275 dev_ifb->rtnl_link_ops = &ifb_link_ops;
276 err = register_netdevice(dev_ifb);
277 if (err < 0)
278 goto err;
279
280 return 0;
281
282err:
283 free_netdev(dev_ifb);
284 return err;
285}
286
287static int __init ifb_init_module(void)
288{
289 int i, err;
290
291 rtnl_lock();
292 err = __rtnl_link_register(&ifb_link_ops);
293
294 for (i = 0; i < numifbs && !err; i++)
295 err = ifb_init_one(i);
296 if (err)
297 __rtnl_link_unregister(&ifb_link_ops);
298 rtnl_unlock();
299
300 return err;
301}
302
303static void __exit ifb_cleanup_module(void)
304{
305 rtnl_link_unregister(&ifb_link_ops);
306}
307
308module_init(ifb_init_module);
309module_exit(ifb_cleanup_module);
310MODULE_LICENSE("GPL");
311MODULE_AUTHOR("Jamal Hadi Salim");
312MODULE_ALIAS_RTNL_LINK("ifb");