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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_q_private {
42 struct net_device *dev;
43 struct tasklet_struct ifb_tasklet;
44 int tasklet_pending;
45 int txqnum;
46 struct sk_buff_head rq;
47 u64 rx_packets;
48 u64 rx_bytes;
49 struct u64_stats_sync rsync;
50
51 struct u64_stats_sync tsync;
52 u64 tx_packets;
53 u64 tx_bytes;
54 struct sk_buff_head tq;
55} ____cacheline_aligned_in_smp;
56
57struct ifb_dev_private {
58 struct ifb_q_private *tx_private;
59};
60
61static netdev_tx_t ifb_xmit(struct sk_buff *skb, struct net_device *dev);
62static int ifb_open(struct net_device *dev);
63static int ifb_close(struct net_device *dev);
64
65static void ifb_ri_tasklet(unsigned long _txp)
66{
67 struct ifb_q_private *txp = (struct ifb_q_private *)_txp;
68 struct netdev_queue *txq;
69 struct sk_buff *skb;
70
71 txq = netdev_get_tx_queue(txp->dev, txp->txqnum);
72 skb = skb_peek(&txp->tq);
73 if (!skb) {
74 if (!__netif_tx_trylock(txq))
75 goto resched;
76 skb_queue_splice_tail_init(&txp->rq, &txp->tq);
77 __netif_tx_unlock(txq);
78 }
79
80 while ((skb = __skb_dequeue(&txp->tq)) != NULL) {
81 u32 from = G_TC_FROM(skb->tc_verd);
82
83 skb->tc_verd = 0;
84 skb->tc_verd = SET_TC_NCLS(skb->tc_verd);
85
86 u64_stats_update_begin(&txp->tsync);
87 txp->tx_packets++;
88 txp->tx_bytes += skb->len;
89 u64_stats_update_end(&txp->tsync);
90
91 rcu_read_lock();
92 skb->dev = dev_get_by_index_rcu(dev_net(txp->dev), skb->skb_iif);
93 if (!skb->dev) {
94 rcu_read_unlock();
95 dev_kfree_skb(skb);
96 txp->dev->stats.tx_dropped++;
97 if (skb_queue_len(&txp->tq) != 0)
98 goto resched;
99 break;
100 }
101 rcu_read_unlock();
102 skb->skb_iif = txp->dev->ifindex;
103
104 if (from & AT_EGRESS) {
105 dev_queue_xmit(skb);
106 } else if (from & AT_INGRESS) {
107 skb_pull(skb, skb->mac_len);
108 netif_receive_skb(skb);
109 } else
110 BUG();
111 }
112
113 if (__netif_tx_trylock(txq)) {
114 skb = skb_peek(&txp->rq);
115 if (!skb) {
116 txp->tasklet_pending = 0;
117 if (netif_tx_queue_stopped(txq))
118 netif_tx_wake_queue(txq);
119 } else {
120 __netif_tx_unlock(txq);
121 goto resched;
122 }
123 __netif_tx_unlock(txq);
124 } else {
125resched:
126 txp->tasklet_pending = 1;
127 tasklet_schedule(&txp->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_dev_private *dp = netdev_priv(dev);
136 struct ifb_q_private *txp = dp->tx_private;
137 unsigned int start;
138 u64 packets, bytes;
139 int i;
140
141 for (i = 0; i < dev->num_tx_queues; i++,txp++) {
142 do {
143 start = u64_stats_fetch_begin_irq(&txp->rsync);
144 packets = txp->rx_packets;
145 bytes = txp->rx_bytes;
146 } while (u64_stats_fetch_retry_irq(&txp->rsync, start));
147 stats->rx_packets += packets;
148 stats->rx_bytes += bytes;
149
150 do {
151 start = u64_stats_fetch_begin_irq(&txp->tsync);
152 packets = txp->tx_packets;
153 bytes = txp->tx_bytes;
154 } while (u64_stats_fetch_retry_irq(&txp->tsync, start));
155 stats->tx_packets += packets;
156 stats->tx_bytes += bytes;
157 }
158 stats->rx_dropped = dev->stats.rx_dropped;
159 stats->tx_dropped = dev->stats.tx_dropped;
160
161 return stats;
162}
163
164static int ifb_dev_init(struct net_device *dev)
165{
166 struct ifb_dev_private *dp = netdev_priv(dev);
167 struct ifb_q_private *txp;
168 int i;
169
170 txp = kcalloc(dev->num_tx_queues, sizeof(*txp), GFP_KERNEL);
171 if (!txp)
172 return -ENOMEM;
173 dp->tx_private = txp;
174 for (i = 0; i < dev->num_tx_queues; i++,txp++) {
175 txp->txqnum = i;
176 txp->dev = dev;
177 __skb_queue_head_init(&txp->rq);
178 __skb_queue_head_init(&txp->tq);
179 u64_stats_init(&txp->rsync);
180 u64_stats_init(&txp->tsync);
181 tasklet_init(&txp->ifb_tasklet, ifb_ri_tasklet,
182 (unsigned long)txp);
183 netif_tx_start_queue(netdev_get_tx_queue(dev, i));
184 }
185 return 0;
186}
187
188static const struct net_device_ops ifb_netdev_ops = {
189 .ndo_open = ifb_open,
190 .ndo_stop = ifb_close,
191 .ndo_get_stats64 = ifb_stats64,
192 .ndo_start_xmit = ifb_xmit,
193 .ndo_validate_addr = eth_validate_addr,
194 .ndo_init = ifb_dev_init,
195};
196
197#define IFB_FEATURES (NETIF_F_HW_CSUM | NETIF_F_SG | NETIF_F_FRAGLIST | \
198 NETIF_F_TSO_ECN | NETIF_F_TSO | NETIF_F_TSO6 | \
199 NETIF_F_GSO_ENCAP_ALL | \
200 NETIF_F_HIGHDMA | NETIF_F_HW_VLAN_CTAG_TX | \
201 NETIF_F_HW_VLAN_STAG_TX)
202
203static void ifb_dev_free(struct net_device *dev)
204{
205 struct ifb_dev_private *dp = netdev_priv(dev);
206 struct ifb_q_private *txp = dp->tx_private;
207 int i;
208
209 for (i = 0; i < dev->num_tx_queues; i++,txp++) {
210 tasklet_kill(&txp->ifb_tasklet);
211 __skb_queue_purge(&txp->rq);
212 __skb_queue_purge(&txp->tq);
213 }
214 kfree(dp->tx_private);
215 free_netdev(dev);
216}
217
218static void ifb_setup(struct net_device *dev)
219{
220 /* Initialize the device structure. */
221 dev->netdev_ops = &ifb_netdev_ops;
222
223 /* Fill in device structure with ethernet-generic values. */
224 ether_setup(dev);
225 dev->tx_queue_len = TX_Q_LIMIT;
226
227 dev->features |= IFB_FEATURES;
228 dev->hw_features |= dev->features;
229 dev->hw_enc_features |= dev->features;
230 dev->vlan_features |= IFB_FEATURES & ~(NETIF_F_HW_VLAN_CTAG_TX |
231 NETIF_F_HW_VLAN_STAG_TX);
232
233 dev->flags |= IFF_NOARP;
234 dev->flags &= ~IFF_MULTICAST;
235 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
236 netif_keep_dst(dev);
237 eth_hw_addr_random(dev);
238 dev->destructor = ifb_dev_free;
239}
240
241static netdev_tx_t ifb_xmit(struct sk_buff *skb, struct net_device *dev)
242{
243 struct ifb_dev_private *dp = netdev_priv(dev);
244 u32 from = G_TC_FROM(skb->tc_verd);
245 struct ifb_q_private *txp = dp->tx_private + skb_get_queue_mapping(skb);
246
247 u64_stats_update_begin(&txp->rsync);
248 txp->rx_packets++;
249 txp->rx_bytes += skb->len;
250 u64_stats_update_end(&txp->rsync);
251
252 if (!(from & (AT_INGRESS|AT_EGRESS)) || !skb->skb_iif) {
253 dev_kfree_skb(skb);
254 dev->stats.rx_dropped++;
255 return NETDEV_TX_OK;
256 }
257
258 if (skb_queue_len(&txp->rq) >= dev->tx_queue_len)
259 netif_tx_stop_queue(netdev_get_tx_queue(dev, txp->txqnum));
260
261 __skb_queue_tail(&txp->rq, skb);
262 if (!txp->tasklet_pending) {
263 txp->tasklet_pending = 1;
264 tasklet_schedule(&txp->ifb_tasklet);
265 }
266
267 return NETDEV_TX_OK;
268}
269
270static int ifb_close(struct net_device *dev)
271{
272 netif_tx_stop_all_queues(dev);
273 return 0;
274}
275
276static int ifb_open(struct net_device *dev)
277{
278 netif_tx_start_all_queues(dev);
279 return 0;
280}
281
282static int ifb_validate(struct nlattr *tb[], struct nlattr *data[])
283{
284 if (tb[IFLA_ADDRESS]) {
285 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
286 return -EINVAL;
287 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
288 return -EADDRNOTAVAIL;
289 }
290 return 0;
291}
292
293static struct rtnl_link_ops ifb_link_ops __read_mostly = {
294 .kind = "ifb",
295 .priv_size = sizeof(struct ifb_dev_private),
296 .setup = ifb_setup,
297 .validate = ifb_validate,
298};
299
300/* Number of ifb devices to be set up by this module.
301 * Note that these legacy devices have one queue.
302 * Prefer something like : ip link add ifb10 numtxqueues 8 type ifb
303 */
304static int numifbs = 2;
305module_param(numifbs, int, 0);
306MODULE_PARM_DESC(numifbs, "Number of ifb devices");
307
308static int __init ifb_init_one(int index)
309{
310 struct net_device *dev_ifb;
311 int err;
312
313 dev_ifb = alloc_netdev(sizeof(struct ifb_dev_private), "ifb%d",
314 NET_NAME_UNKNOWN, ifb_setup);
315
316 if (!dev_ifb)
317 return -ENOMEM;
318
319 dev_ifb->rtnl_link_ops = &ifb_link_ops;
320 err = register_netdevice(dev_ifb);
321 if (err < 0)
322 goto err;
323
324 return 0;
325
326err:
327 free_netdev(dev_ifb);
328 return err;
329}
330
331static int __init ifb_init_module(void)
332{
333 int i, err;
334
335 rtnl_lock();
336 err = __rtnl_link_register(&ifb_link_ops);
337 if (err < 0)
338 goto out;
339
340 for (i = 0; i < numifbs && !err; i++) {
341 err = ifb_init_one(i);
342 cond_resched();
343 }
344 if (err)
345 __rtnl_link_unregister(&ifb_link_ops);
346
347out:
348 rtnl_unlock();
349
350 return err;
351}
352
353static void __exit ifb_cleanup_module(void)
354{
355 rtnl_link_unregister(&ifb_link_ops);
356}
357
358module_init(ifb_init_module);
359module_exit(ifb_cleanup_module);
360MODULE_LICENSE("GPL");
361MODULE_AUTHOR("Jamal Hadi Salim");
362MODULE_ALIAS_RTNL_LINK("ifb");