Commit | Line | Data |
---|---|---|
6aa20a22 | 1 | /* drivers/net/ifb.c: |
253af423 JHS |
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 | |
6aa20a22 JG |
11 | dropping. |
12 | ||
253af423 JHS |
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. | |
6aa20a22 | 24 | |
253af423 | 25 | Authors: Jamal Hadi Salim (2005) |
6aa20a22 | 26 | |
253af423 JHS |
27 | */ |
28 | ||
29 | ||
253af423 JHS |
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> | |
6aa20a22 | 36 | #include <net/pkt_sched.h> |
253af423 JHS |
37 | |
38 | #define TX_TIMEOUT (2*HZ) | |
6aa20a22 | 39 | |
253af423 JHS |
40 | #define TX_Q_LIMIT 32 |
41 | struct ifb_private { | |
42 | struct net_device_stats stats; | |
43 | struct tasklet_struct ifb_tasklet; | |
44 | int tasklet_pending; | |
45 | /* mostly debug stats leave in for now */ | |
46 | unsigned long st_task_enter; /* tasklet entered */ | |
47 | unsigned long st_txq_refl_try; /* transmit queue refill attempt */ | |
48 | unsigned long st_rxq_enter; /* receive queue entered */ | |
49 | unsigned long st_rx2tx_tran; /* receive to trasmit transfers */ | |
50 | unsigned long st_rxq_notenter; /*receiveQ not entered, resched */ | |
51 | unsigned long st_rx_frm_egr; /* received from egress path */ | |
52 | unsigned long st_rx_frm_ing; /* received from ingress path */ | |
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 | ||
35eaa31e | 59 | static int numifbs = 2; |
253af423 JHS |
60 | |
61 | static void ri_tasklet(unsigned long dev); | |
62 | static int ifb_xmit(struct sk_buff *skb, struct net_device *dev); | |
63 | static struct net_device_stats *ifb_get_stats(struct net_device *dev); | |
64 | static int ifb_open(struct net_device *dev); | |
65 | static int ifb_close(struct net_device *dev); | |
66 | ||
6aa20a22 | 67 | static void ri_tasklet(unsigned long dev) |
253af423 JHS |
68 | { |
69 | ||
70 | struct net_device *_dev = (struct net_device *)dev; | |
71 | struct ifb_private *dp = netdev_priv(_dev); | |
72 | struct net_device_stats *stats = &dp->stats; | |
73 | struct sk_buff *skb; | |
74 | ||
75 | dp->st_task_enter++; | |
76 | if ((skb = skb_peek(&dp->tq)) == NULL) { | |
77 | dp->st_txq_refl_try++; | |
932ff279 | 78 | if (netif_tx_trylock(_dev)) { |
253af423 JHS |
79 | dp->st_rxq_enter++; |
80 | while ((skb = skb_dequeue(&dp->rq)) != NULL) { | |
81 | skb_queue_tail(&dp->tq, skb); | |
82 | dp->st_rx2tx_tran++; | |
83 | } | |
932ff279 | 84 | netif_tx_unlock(_dev); |
253af423 JHS |
85 | } else { |
86 | /* reschedule */ | |
87 | dp->st_rxq_notenter++; | |
88 | goto resched; | |
89 | } | |
90 | } | |
91 | ||
92 | while ((skb = skb_dequeue(&dp->tq)) != NULL) { | |
93 | u32 from = G_TC_FROM(skb->tc_verd); | |
94 | ||
95 | skb->tc_verd = 0; | |
96 | skb->tc_verd = SET_TC_NCLS(skb->tc_verd); | |
97 | stats->tx_packets++; | |
98 | stats->tx_bytes +=skb->len; | |
c01003c2 PM |
99 | |
100 | skb->dev = __dev_get_by_index(skb->iif); | |
101 | if (!skb->dev) { | |
102 | dev_kfree_skb(skb); | |
103 | stats->tx_dropped++; | |
104 | break; | |
105 | } | |
106 | skb->iif = _dev->ifindex; | |
107 | ||
253af423 JHS |
108 | if (from & AT_EGRESS) { |
109 | dp->st_rx_frm_egr++; | |
110 | dev_queue_xmit(skb); | |
111 | } else if (from & AT_INGRESS) { | |
253af423 | 112 | dp->st_rx_frm_ing++; |
c01003c2 | 113 | skb_pull(skb, skb->dev->hard_header_len); |
253af423 | 114 | netif_rx(skb); |
c01003c2 PM |
115 | } else |
116 | BUG(); | |
253af423 JHS |
117 | } |
118 | ||
932ff279 | 119 | if (netif_tx_trylock(_dev)) { |
253af423 JHS |
120 | dp->st_rxq_check++; |
121 | if ((skb = skb_peek(&dp->rq)) == NULL) { | |
122 | dp->tasklet_pending = 0; | |
123 | if (netif_queue_stopped(_dev)) | |
124 | netif_wake_queue(_dev); | |
125 | } else { | |
126 | dp->st_rxq_rsch++; | |
932ff279 | 127 | netif_tx_unlock(_dev); |
253af423 JHS |
128 | goto resched; |
129 | } | |
932ff279 | 130 | netif_tx_unlock(_dev); |
253af423 JHS |
131 | } else { |
132 | resched: | |
133 | dp->tasklet_pending = 1; | |
134 | tasklet_schedule(&dp->ifb_tasklet); | |
135 | } | |
136 | ||
137 | } | |
138 | ||
139 | static void __init ifb_setup(struct net_device *dev) | |
140 | { | |
141 | /* Initialize the device structure. */ | |
142 | dev->get_stats = ifb_get_stats; | |
143 | dev->hard_start_xmit = ifb_xmit; | |
144 | dev->open = &ifb_open; | |
145 | dev->stop = &ifb_close; | |
146 | ||
147 | /* Fill in device structure with ethernet-generic values. */ | |
148 | ether_setup(dev); | |
149 | dev->tx_queue_len = TX_Q_LIMIT; | |
150 | dev->change_mtu = NULL; | |
151 | dev->flags |= IFF_NOARP; | |
152 | dev->flags &= ~IFF_MULTICAST; | |
153 | SET_MODULE_OWNER(dev); | |
154 | random_ether_addr(dev->dev_addr); | |
155 | } | |
156 | ||
157 | static int ifb_xmit(struct sk_buff *skb, struct net_device *dev) | |
158 | { | |
159 | struct ifb_private *dp = netdev_priv(dev); | |
160 | struct net_device_stats *stats = &dp->stats; | |
161 | int ret = 0; | |
162 | u32 from = G_TC_FROM(skb->tc_verd); | |
163 | ||
3136dcb3 | 164 | stats->rx_packets++; |
165 | stats->rx_bytes+=skb->len; | |
253af423 | 166 | |
c01003c2 | 167 | if (!(from & (AT_INGRESS|AT_EGRESS)) || !skb->iif) { |
253af423 JHS |
168 | dev_kfree_skb(skb); |
169 | stats->rx_dropped++; | |
170 | return ret; | |
253af423 JHS |
171 | } |
172 | ||
173 | if (skb_queue_len(&dp->rq) >= dev->tx_queue_len) { | |
174 | netif_stop_queue(dev); | |
175 | } | |
176 | ||
177 | dev->trans_start = jiffies; | |
178 | skb_queue_tail(&dp->rq, skb); | |
179 | if (!dp->tasklet_pending) { | |
180 | dp->tasklet_pending = 1; | |
181 | tasklet_schedule(&dp->ifb_tasklet); | |
182 | } | |
183 | ||
184 | return ret; | |
185 | } | |
186 | ||
187 | static struct net_device_stats *ifb_get_stats(struct net_device *dev) | |
188 | { | |
189 | struct ifb_private *dp = netdev_priv(dev); | |
190 | struct net_device_stats *stats = &dp->stats; | |
191 | ||
192 | pr_debug("tasklets stats %ld:%ld:%ld:%ld:%ld:%ld:%ld:%ld:%ld \n", | |
6aa20a22 | 193 | dp->st_task_enter, dp->st_txq_refl_try, dp->st_rxq_enter, |
8057de64 ZB |
194 | dp->st_rx2tx_tran, dp->st_rxq_notenter, dp->st_rx_frm_egr, |
195 | dp->st_rx_frm_ing, dp->st_rxq_check, dp->st_rxq_rsch); | |
253af423 JHS |
196 | |
197 | return stats; | |
198 | } | |
199 | ||
200 | static struct net_device **ifbs; | |
201 | ||
202 | /* Number of ifb devices to be set up by this module. */ | |
203 | module_param(numifbs, int, 0); | |
204 | MODULE_PARM_DESC(numifbs, "Number of ifb devices"); | |
205 | ||
206 | static int ifb_close(struct net_device *dev) | |
207 | { | |
208 | struct ifb_private *dp = netdev_priv(dev); | |
209 | ||
210 | tasklet_kill(&dp->ifb_tasklet); | |
211 | netif_stop_queue(dev); | |
212 | skb_queue_purge(&dp->rq); | |
213 | skb_queue_purge(&dp->tq); | |
214 | return 0; | |
215 | } | |
216 | ||
217 | static int ifb_open(struct net_device *dev) | |
218 | { | |
219 | struct ifb_private *dp = netdev_priv(dev); | |
220 | ||
221 | tasklet_init(&dp->ifb_tasklet, ri_tasklet, (unsigned long)dev); | |
222 | skb_queue_head_init(&dp->rq); | |
223 | skb_queue_head_init(&dp->tq); | |
224 | netif_start_queue(dev); | |
225 | ||
226 | return 0; | |
227 | } | |
228 | ||
229 | static int __init ifb_init_one(int index) | |
230 | { | |
231 | struct net_device *dev_ifb; | |
232 | int err; | |
233 | ||
234 | dev_ifb = alloc_netdev(sizeof(struct ifb_private), | |
235 | "ifb%d", ifb_setup); | |
236 | ||
237 | if (!dev_ifb) | |
238 | return -ENOMEM; | |
239 | ||
240 | if ((err = register_netdev(dev_ifb))) { | |
241 | free_netdev(dev_ifb); | |
242 | dev_ifb = NULL; | |
243 | } else { | |
6aa20a22 | 244 | ifbs[index] = dev_ifb; |
253af423 JHS |
245 | } |
246 | ||
247 | return err; | |
248 | } | |
249 | ||
250 | static void ifb_free_one(int index) | |
251 | { | |
252 | unregister_netdev(ifbs[index]); | |
253 | free_netdev(ifbs[index]); | |
6aa20a22 | 254 | } |
253af423 JHS |
255 | |
256 | static int __init ifb_init_module(void) | |
6aa20a22 | 257 | { |
253af423 | 258 | int i, err = 0; |
6aa20a22 | 259 | ifbs = kmalloc(numifbs * sizeof(void *), GFP_KERNEL); |
253af423 | 260 | if (!ifbs) |
6aa20a22 | 261 | return -ENOMEM; |
253af423 | 262 | for (i = 0; i < numifbs && !err; i++) |
6aa20a22 JG |
263 | err = ifb_init_one(i); |
264 | if (err) { | |
bcdddfb6 LT |
265 | i--; |
266 | while (--i >= 0) | |
253af423 JHS |
267 | ifb_free_one(i); |
268 | } | |
269 | ||
270 | return err; | |
6aa20a22 | 271 | } |
253af423 JHS |
272 | |
273 | static void __exit ifb_cleanup_module(void) | |
274 | { | |
275 | int i; | |
276 | ||
6aa20a22 JG |
277 | for (i = 0; i < numifbs; i++) |
278 | ifb_free_one(i); | |
279 | kfree(ifbs); | |
253af423 JHS |
280 | } |
281 | ||
282 | module_init(ifb_init_module); | |
283 | module_exit(ifb_cleanup_module); | |
284 | MODULE_LICENSE("GPL"); | |
285 | MODULE_AUTHOR("Jamal Hadi Salim"); |