3 The purpose of this driver is to provide a device that allows
4 for sharing of resources:
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.
10 2) Allows for queueing incoming traffic for shaping instead of
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.
17 You need the tc action mirror or redirect to feed this device
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.
25 Authors: Jamal Hadi Salim (2005)
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>
41 struct ifb_q_private
{
42 struct net_device
*dev
;
43 struct tasklet_struct ifb_tasklet
;
46 struct sk_buff_head rq
;
49 struct u64_stats_sync rsync
;
51 struct u64_stats_sync tsync
;
54 struct sk_buff_head tq
;
55 } ____cacheline_aligned_in_smp
;
57 struct ifb_dev_private
{
58 struct ifb_q_private
*tx_private
;
61 static netdev_tx_t
ifb_xmit(struct sk_buff
*skb
, struct net_device
*dev
);
62 static int ifb_open(struct net_device
*dev
);
63 static int ifb_close(struct net_device
*dev
);
65 static void ifb_ri_tasklet(unsigned long _txp
)
67 struct ifb_q_private
*txp
= (struct ifb_q_private
*)_txp
;
68 struct netdev_queue
*txq
;
71 txq
= netdev_get_tx_queue(txp
->dev
, txp
->txqnum
);
72 skb
= skb_peek(&txp
->tq
);
74 if (!__netif_tx_trylock(txq
))
76 skb_queue_splice_tail_init(&txp
->rq
, &txp
->tq
);
77 __netif_tx_unlock(txq
);
80 while ((skb
= __skb_dequeue(&txp
->tq
)) != NULL
) {
81 u32 from
= G_TC_FROM(skb
->tc_verd
);
84 skb
->tc_verd
= SET_TC_NCLS(skb
->tc_verd
);
86 u64_stats_update_begin(&txp
->tsync
);
88 txp
->tx_bytes
+= skb
->len
;
89 u64_stats_update_end(&txp
->tsync
);
92 skb
->dev
= dev_get_by_index_rcu(dev_net(txp
->dev
), skb
->skb_iif
);
96 txp
->dev
->stats
.tx_dropped
++;
97 if (skb_queue_len(&txp
->tq
) != 0)
102 skb
->skb_iif
= txp
->dev
->ifindex
;
104 if (from
& AT_EGRESS
) {
106 } else if (from
& AT_INGRESS
) {
107 skb_pull(skb
, skb
->mac_len
);
108 netif_receive_skb(skb
);
113 if (__netif_tx_trylock(txq
)) {
114 skb
= skb_peek(&txp
->rq
);
116 txp
->tasklet_pending
= 0;
117 if (netif_tx_queue_stopped(txq
))
118 netif_tx_wake_queue(txq
);
120 __netif_tx_unlock(txq
);
123 __netif_tx_unlock(txq
);
126 txp
->tasklet_pending
= 1;
127 tasklet_schedule(&txp
->ifb_tasklet
);
132 static struct rtnl_link_stats64
*ifb_stats64(struct net_device
*dev
,
133 struct rtnl_link_stats64
*stats
)
135 struct ifb_dev_private
*dp
= netdev_priv(dev
);
136 struct ifb_q_private
*txp
= dp
->tx_private
;
141 for (i
= 0; i
< dev
->num_tx_queues
; i
++,txp
++) {
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
;
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
;
158 stats
->rx_dropped
= dev
->stats
.rx_dropped
;
159 stats
->tx_dropped
= dev
->stats
.tx_dropped
;
164 static int ifb_dev_init(struct net_device
*dev
)
166 struct ifb_dev_private
*dp
= netdev_priv(dev
);
167 struct ifb_q_private
*txp
;
170 txp
= kcalloc(dev
->num_tx_queues
, sizeof(*txp
), GFP_KERNEL
);
173 dp
->tx_private
= txp
;
174 for (i
= 0; i
< dev
->num_tx_queues
; i
++,txp
++) {
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
,
183 netif_tx_start_queue(netdev_get_tx_queue(dev
, i
));
188 static 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
,
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)
203 static void ifb_dev_free(struct net_device
*dev
)
205 struct ifb_dev_private
*dp
= netdev_priv(dev
);
206 struct ifb_q_private
*txp
= dp
->tx_private
;
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
);
214 kfree(dp
->tx_private
);
218 static void ifb_setup(struct net_device
*dev
)
220 /* Initialize the device structure. */
221 dev
->netdev_ops
= &ifb_netdev_ops
;
223 /* Fill in device structure with ethernet-generic values. */
225 dev
->tx_queue_len
= TX_Q_LIMIT
;
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
);
233 dev
->flags
|= IFF_NOARP
;
234 dev
->flags
&= ~IFF_MULTICAST
;
235 dev
->priv_flags
&= ~IFF_TX_SKB_SHARING
;
237 eth_hw_addr_random(dev
);
238 dev
->destructor
= ifb_dev_free
;
241 static netdev_tx_t
ifb_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
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
);
247 u64_stats_update_begin(&txp
->rsync
);
249 txp
->rx_bytes
+= skb
->len
;
250 u64_stats_update_end(&txp
->rsync
);
252 if (!(from
& (AT_INGRESS
|AT_EGRESS
)) || !skb
->skb_iif
) {
254 dev
->stats
.rx_dropped
++;
258 if (skb_queue_len(&txp
->rq
) >= dev
->tx_queue_len
)
259 netif_tx_stop_queue(netdev_get_tx_queue(dev
, txp
->txqnum
));
261 __skb_queue_tail(&txp
->rq
, skb
);
262 if (!txp
->tasklet_pending
) {
263 txp
->tasklet_pending
= 1;
264 tasklet_schedule(&txp
->ifb_tasklet
);
270 static int ifb_close(struct net_device
*dev
)
272 netif_tx_stop_all_queues(dev
);
276 static int ifb_open(struct net_device
*dev
)
278 netif_tx_start_all_queues(dev
);
282 static int ifb_validate(struct nlattr
*tb
[], struct nlattr
*data
[])
284 if (tb
[IFLA_ADDRESS
]) {
285 if (nla_len(tb
[IFLA_ADDRESS
]) != ETH_ALEN
)
287 if (!is_valid_ether_addr(nla_data(tb
[IFLA_ADDRESS
])))
288 return -EADDRNOTAVAIL
;
293 static struct rtnl_link_ops ifb_link_ops __read_mostly
= {
295 .priv_size
= sizeof(struct ifb_dev_private
),
297 .validate
= ifb_validate
,
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
304 static int numifbs
= 2;
305 module_param(numifbs
, int, 0);
306 MODULE_PARM_DESC(numifbs
, "Number of ifb devices");
308 static int __init
ifb_init_one(int index
)
310 struct net_device
*dev_ifb
;
313 dev_ifb
= alloc_netdev(sizeof(struct ifb_dev_private
), "ifb%d",
314 NET_NAME_UNKNOWN
, ifb_setup
);
319 dev_ifb
->rtnl_link_ops
= &ifb_link_ops
;
320 err
= register_netdevice(dev_ifb
);
327 free_netdev(dev_ifb
);
331 static int __init
ifb_init_module(void)
336 err
= __rtnl_link_register(&ifb_link_ops
);
340 for (i
= 0; i
< numifbs
&& !err
; i
++) {
341 err
= ifb_init_one(i
);
345 __rtnl_link_unregister(&ifb_link_ops
);
353 static void __exit
ifb_cleanup_module(void)
355 rtnl_link_unregister(&ifb_link_ops
);
358 module_init(ifb_init_module
);
359 module_exit(ifb_cleanup_module
);
360 MODULE_LICENSE("GPL");
361 MODULE_AUTHOR("Jamal Hadi Salim");
362 MODULE_ALIAS_RTNL_LINK("ifb");