Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 1 | /* drivers/net/ifb.c: |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 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 |
Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 11 | dropping. |
| 12 | |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 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. |
Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 24 | |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 25 | Authors: Jamal Hadi Salim (2005) |
Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 26 | |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 27 | */ |
| 28 | |
| 29 | |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 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> |
Patrick McHardy | 62b7ffc | 2007-06-13 12:04:51 -0700 | [diff] [blame^] | 36 | #include <linux/list.h> |
Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 37 | #include <net/pkt_sched.h> |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 38 | |
| 39 | #define TX_TIMEOUT (2*HZ) |
Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 40 | |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 41 | #define TX_Q_LIMIT 32 |
| 42 | struct ifb_private { |
Patrick McHardy | 62b7ffc | 2007-06-13 12:04:51 -0700 | [diff] [blame^] | 43 | struct list_head list; |
| 44 | struct net_device *dev; |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 45 | struct net_device_stats stats; |
| 46 | struct tasklet_struct ifb_tasklet; |
| 47 | int tasklet_pending; |
| 48 | /* mostly debug stats leave in for now */ |
| 49 | unsigned long st_task_enter; /* tasklet entered */ |
| 50 | unsigned long st_txq_refl_try; /* transmit queue refill attempt */ |
| 51 | unsigned long st_rxq_enter; /* receive queue entered */ |
| 52 | unsigned long st_rx2tx_tran; /* receive to trasmit transfers */ |
| 53 | unsigned long st_rxq_notenter; /*receiveQ not entered, resched */ |
| 54 | unsigned long st_rx_frm_egr; /* received from egress path */ |
| 55 | unsigned long st_rx_frm_ing; /* received from ingress path */ |
| 56 | unsigned long st_rxq_check; |
| 57 | unsigned long st_rxq_rsch; |
| 58 | struct sk_buff_head rq; |
| 59 | struct sk_buff_head tq; |
| 60 | }; |
| 61 | |
Richard Lucassen | 35eaa31 | 2006-02-23 16:23:51 -0800 | [diff] [blame] | 62 | static int numifbs = 2; |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 63 | |
| 64 | static void ri_tasklet(unsigned long dev); |
| 65 | static int ifb_xmit(struct sk_buff *skb, struct net_device *dev); |
| 66 | static struct net_device_stats *ifb_get_stats(struct net_device *dev); |
| 67 | static int ifb_open(struct net_device *dev); |
| 68 | static int ifb_close(struct net_device *dev); |
| 69 | |
Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 70 | static void ri_tasklet(unsigned long dev) |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 71 | { |
| 72 | |
| 73 | struct net_device *_dev = (struct net_device *)dev; |
| 74 | struct ifb_private *dp = netdev_priv(_dev); |
| 75 | struct net_device_stats *stats = &dp->stats; |
| 76 | struct sk_buff *skb; |
| 77 | |
| 78 | dp->st_task_enter++; |
| 79 | if ((skb = skb_peek(&dp->tq)) == NULL) { |
| 80 | dp->st_txq_refl_try++; |
Herbert Xu | 932ff27 | 2006-06-09 12:20:56 -0700 | [diff] [blame] | 81 | if (netif_tx_trylock(_dev)) { |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 82 | dp->st_rxq_enter++; |
| 83 | while ((skb = skb_dequeue(&dp->rq)) != NULL) { |
| 84 | skb_queue_tail(&dp->tq, skb); |
| 85 | dp->st_rx2tx_tran++; |
| 86 | } |
Herbert Xu | 932ff27 | 2006-06-09 12:20:56 -0700 | [diff] [blame] | 87 | netif_tx_unlock(_dev); |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 88 | } else { |
| 89 | /* reschedule */ |
| 90 | dp->st_rxq_notenter++; |
| 91 | goto resched; |
| 92 | } |
| 93 | } |
| 94 | |
| 95 | while ((skb = skb_dequeue(&dp->tq)) != NULL) { |
| 96 | u32 from = G_TC_FROM(skb->tc_verd); |
| 97 | |
| 98 | skb->tc_verd = 0; |
| 99 | skb->tc_verd = SET_TC_NCLS(skb->tc_verd); |
| 100 | stats->tx_packets++; |
| 101 | stats->tx_bytes +=skb->len; |
Patrick McHardy | c01003c | 2007-03-29 11:46:52 -0700 | [diff] [blame] | 102 | |
| 103 | skb->dev = __dev_get_by_index(skb->iif); |
| 104 | if (!skb->dev) { |
| 105 | dev_kfree_skb(skb); |
| 106 | stats->tx_dropped++; |
| 107 | break; |
| 108 | } |
| 109 | skb->iif = _dev->ifindex; |
| 110 | |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 111 | if (from & AT_EGRESS) { |
| 112 | dp->st_rx_frm_egr++; |
| 113 | dev_queue_xmit(skb); |
| 114 | } else if (from & AT_INGRESS) { |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 115 | dp->st_rx_frm_ing++; |
Patrick McHardy | c01003c | 2007-03-29 11:46:52 -0700 | [diff] [blame] | 116 | skb_pull(skb, skb->dev->hard_header_len); |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 117 | netif_rx(skb); |
Patrick McHardy | c01003c | 2007-03-29 11:46:52 -0700 | [diff] [blame] | 118 | } else |
| 119 | BUG(); |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 120 | } |
| 121 | |
Herbert Xu | 932ff27 | 2006-06-09 12:20:56 -0700 | [diff] [blame] | 122 | if (netif_tx_trylock(_dev)) { |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 123 | dp->st_rxq_check++; |
| 124 | if ((skb = skb_peek(&dp->rq)) == NULL) { |
| 125 | dp->tasklet_pending = 0; |
| 126 | if (netif_queue_stopped(_dev)) |
| 127 | netif_wake_queue(_dev); |
| 128 | } else { |
| 129 | dp->st_rxq_rsch++; |
Herbert Xu | 932ff27 | 2006-06-09 12:20:56 -0700 | [diff] [blame] | 130 | netif_tx_unlock(_dev); |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 131 | goto resched; |
| 132 | } |
Herbert Xu | 932ff27 | 2006-06-09 12:20:56 -0700 | [diff] [blame] | 133 | netif_tx_unlock(_dev); |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 134 | } else { |
| 135 | resched: |
| 136 | dp->tasklet_pending = 1; |
| 137 | tasklet_schedule(&dp->ifb_tasklet); |
| 138 | } |
| 139 | |
| 140 | } |
| 141 | |
| 142 | static void __init ifb_setup(struct net_device *dev) |
| 143 | { |
| 144 | /* Initialize the device structure. */ |
| 145 | dev->get_stats = ifb_get_stats; |
| 146 | dev->hard_start_xmit = ifb_xmit; |
| 147 | dev->open = &ifb_open; |
| 148 | dev->stop = &ifb_close; |
| 149 | |
| 150 | /* Fill in device structure with ethernet-generic values. */ |
| 151 | ether_setup(dev); |
| 152 | dev->tx_queue_len = TX_Q_LIMIT; |
| 153 | dev->change_mtu = NULL; |
| 154 | dev->flags |= IFF_NOARP; |
| 155 | dev->flags &= ~IFF_MULTICAST; |
| 156 | SET_MODULE_OWNER(dev); |
| 157 | random_ether_addr(dev->dev_addr); |
| 158 | } |
| 159 | |
| 160 | static int ifb_xmit(struct sk_buff *skb, struct net_device *dev) |
| 161 | { |
| 162 | struct ifb_private *dp = netdev_priv(dev); |
| 163 | struct net_device_stats *stats = &dp->stats; |
| 164 | int ret = 0; |
| 165 | u32 from = G_TC_FROM(skb->tc_verd); |
| 166 | |
dean gaudet | 3136dcb | 2007-01-01 19:39:09 -0800 | [diff] [blame] | 167 | stats->rx_packets++; |
| 168 | stats->rx_bytes+=skb->len; |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 169 | |
Patrick McHardy | c01003c | 2007-03-29 11:46:52 -0700 | [diff] [blame] | 170 | if (!(from & (AT_INGRESS|AT_EGRESS)) || !skb->iif) { |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 171 | dev_kfree_skb(skb); |
| 172 | stats->rx_dropped++; |
| 173 | return ret; |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 174 | } |
| 175 | |
| 176 | if (skb_queue_len(&dp->rq) >= dev->tx_queue_len) { |
| 177 | netif_stop_queue(dev); |
| 178 | } |
| 179 | |
| 180 | dev->trans_start = jiffies; |
| 181 | skb_queue_tail(&dp->rq, skb); |
| 182 | if (!dp->tasklet_pending) { |
| 183 | dp->tasklet_pending = 1; |
| 184 | tasklet_schedule(&dp->ifb_tasklet); |
| 185 | } |
| 186 | |
| 187 | return ret; |
| 188 | } |
| 189 | |
| 190 | static struct net_device_stats *ifb_get_stats(struct net_device *dev) |
| 191 | { |
| 192 | struct ifb_private *dp = netdev_priv(dev); |
| 193 | struct net_device_stats *stats = &dp->stats; |
| 194 | |
| 195 | pr_debug("tasklets stats %ld:%ld:%ld:%ld:%ld:%ld:%ld:%ld:%ld \n", |
Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 196 | dp->st_task_enter, dp->st_txq_refl_try, dp->st_rxq_enter, |
Zach Brown | 8057de6 | 2006-10-03 01:16:10 -0700 | [diff] [blame] | 197 | dp->st_rx2tx_tran, dp->st_rxq_notenter, dp->st_rx_frm_egr, |
| 198 | dp->st_rx_frm_ing, dp->st_rxq_check, dp->st_rxq_rsch); |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 199 | |
| 200 | return stats; |
| 201 | } |
| 202 | |
Patrick McHardy | 62b7ffc | 2007-06-13 12:04:51 -0700 | [diff] [blame^] | 203 | static LIST_HEAD(ifbs); |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 204 | |
| 205 | /* Number of ifb devices to be set up by this module. */ |
| 206 | module_param(numifbs, int, 0); |
| 207 | MODULE_PARM_DESC(numifbs, "Number of ifb devices"); |
| 208 | |
| 209 | static int ifb_close(struct net_device *dev) |
| 210 | { |
| 211 | struct ifb_private *dp = netdev_priv(dev); |
| 212 | |
| 213 | tasklet_kill(&dp->ifb_tasklet); |
| 214 | netif_stop_queue(dev); |
| 215 | skb_queue_purge(&dp->rq); |
| 216 | skb_queue_purge(&dp->tq); |
| 217 | return 0; |
| 218 | } |
| 219 | |
| 220 | static int ifb_open(struct net_device *dev) |
| 221 | { |
| 222 | struct ifb_private *dp = netdev_priv(dev); |
| 223 | |
| 224 | tasklet_init(&dp->ifb_tasklet, ri_tasklet, (unsigned long)dev); |
| 225 | skb_queue_head_init(&dp->rq); |
| 226 | skb_queue_head_init(&dp->tq); |
| 227 | netif_start_queue(dev); |
| 228 | |
| 229 | return 0; |
| 230 | } |
| 231 | |
| 232 | static int __init ifb_init_one(int index) |
| 233 | { |
| 234 | struct net_device *dev_ifb; |
Patrick McHardy | 62b7ffc | 2007-06-13 12:04:51 -0700 | [diff] [blame^] | 235 | struct ifb_private *priv; |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 236 | int err; |
| 237 | |
| 238 | dev_ifb = alloc_netdev(sizeof(struct ifb_private), |
| 239 | "ifb%d", ifb_setup); |
| 240 | |
| 241 | if (!dev_ifb) |
| 242 | return -ENOMEM; |
| 243 | |
| 244 | if ((err = register_netdev(dev_ifb))) { |
| 245 | free_netdev(dev_ifb); |
| 246 | dev_ifb = NULL; |
| 247 | } else { |
Patrick McHardy | 62b7ffc | 2007-06-13 12:04:51 -0700 | [diff] [blame^] | 248 | priv = netdev_priv(dev_ifb); |
| 249 | priv->dev = dev_ifb; |
| 250 | list_add_tail(&priv->list, &ifbs); |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 251 | } |
| 252 | |
| 253 | return err; |
| 254 | } |
| 255 | |
Patrick McHardy | 62b7ffc | 2007-06-13 12:04:51 -0700 | [diff] [blame^] | 256 | static void ifb_free_one(struct net_device *dev) |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 257 | { |
Patrick McHardy | 62b7ffc | 2007-06-13 12:04:51 -0700 | [diff] [blame^] | 258 | struct ifb_private *priv = netdev_priv(dev); |
| 259 | |
| 260 | list_del(&priv->list); |
| 261 | unregister_netdev(dev); |
| 262 | free_netdev(dev); |
Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 263 | } |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 264 | |
| 265 | static int __init ifb_init_module(void) |
Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 266 | { |
Patrick McHardy | 62b7ffc | 2007-06-13 12:04:51 -0700 | [diff] [blame^] | 267 | struct ifb_private *priv, *next; |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 268 | int i, err = 0; |
Patrick McHardy | 62b7ffc | 2007-06-13 12:04:51 -0700 | [diff] [blame^] | 269 | |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 270 | for (i = 0; i < numifbs && !err; i++) |
Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 271 | err = ifb_init_one(i); |
| 272 | if (err) { |
Patrick McHardy | 62b7ffc | 2007-06-13 12:04:51 -0700 | [diff] [blame^] | 273 | list_for_each_entry_safe(priv, next, &ifbs, list) |
| 274 | ifb_free_one(priv->dev); |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 275 | } |
| 276 | |
| 277 | return err; |
Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 278 | } |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 279 | |
| 280 | static void __exit ifb_cleanup_module(void) |
| 281 | { |
Patrick McHardy | 62b7ffc | 2007-06-13 12:04:51 -0700 | [diff] [blame^] | 282 | struct ifb_private *priv, *next; |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 283 | |
Patrick McHardy | 62b7ffc | 2007-06-13 12:04:51 -0700 | [diff] [blame^] | 284 | list_for_each_entry_safe(priv, next, &ifbs, list) |
| 285 | ifb_free_one(priv->dev); |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 286 | } |
| 287 | |
| 288 | module_init(ifb_init_module); |
| 289 | module_exit(ifb_cleanup_module); |
| 290 | MODULE_LICENSE("GPL"); |
| 291 | MODULE_AUTHOR("Jamal Hadi Salim"); |