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> |
Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 36 | #include <net/pkt_sched.h> |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 37 | |
| 38 | #define TX_TIMEOUT (2*HZ) |
Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 39 | |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 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 | |
Richard Lucassen | 35eaa31 | 2006-02-23 16:23:51 -0800 | [diff] [blame] | 59 | static int numifbs = 2; |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 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 | |
Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 67 | static void ri_tasklet(unsigned long dev) |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 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++; |
Herbert Xu | 932ff27 | 2006-06-09 12:20:56 -0700 | [diff] [blame] | 78 | if (netif_tx_trylock(_dev)) { |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 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 | } |
Herbert Xu | 932ff27 | 2006-06-09 12:20:56 -0700 | [diff] [blame] | 84 | netif_tx_unlock(_dev); |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 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; |
| 99 | if (from & AT_EGRESS) { |
| 100 | dp->st_rx_frm_egr++; |
| 101 | dev_queue_xmit(skb); |
| 102 | } else if (from & AT_INGRESS) { |
| 103 | |
| 104 | dp->st_rx_frm_ing++; |
| 105 | netif_rx(skb); |
| 106 | } else { |
| 107 | dev_kfree_skb(skb); |
| 108 | stats->tx_dropped++; |
| 109 | } |
| 110 | } |
| 111 | |
Herbert Xu | 932ff27 | 2006-06-09 12:20:56 -0700 | [diff] [blame] | 112 | if (netif_tx_trylock(_dev)) { |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 113 | dp->st_rxq_check++; |
| 114 | if ((skb = skb_peek(&dp->rq)) == NULL) { |
| 115 | dp->tasklet_pending = 0; |
| 116 | if (netif_queue_stopped(_dev)) |
| 117 | netif_wake_queue(_dev); |
| 118 | } else { |
| 119 | dp->st_rxq_rsch++; |
Herbert Xu | 932ff27 | 2006-06-09 12:20:56 -0700 | [diff] [blame] | 120 | netif_tx_unlock(_dev); |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 121 | goto resched; |
| 122 | } |
Herbert Xu | 932ff27 | 2006-06-09 12:20:56 -0700 | [diff] [blame] | 123 | netif_tx_unlock(_dev); |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 124 | } else { |
| 125 | resched: |
| 126 | dp->tasklet_pending = 1; |
| 127 | tasklet_schedule(&dp->ifb_tasklet); |
| 128 | } |
| 129 | |
| 130 | } |
| 131 | |
| 132 | static void __init ifb_setup(struct net_device *dev) |
| 133 | { |
| 134 | /* Initialize the device structure. */ |
| 135 | dev->get_stats = ifb_get_stats; |
| 136 | dev->hard_start_xmit = ifb_xmit; |
| 137 | dev->open = &ifb_open; |
| 138 | dev->stop = &ifb_close; |
| 139 | |
| 140 | /* Fill in device structure with ethernet-generic values. */ |
| 141 | ether_setup(dev); |
| 142 | dev->tx_queue_len = TX_Q_LIMIT; |
| 143 | dev->change_mtu = NULL; |
| 144 | dev->flags |= IFF_NOARP; |
| 145 | dev->flags &= ~IFF_MULTICAST; |
| 146 | SET_MODULE_OWNER(dev); |
| 147 | random_ether_addr(dev->dev_addr); |
| 148 | } |
| 149 | |
| 150 | static int ifb_xmit(struct sk_buff *skb, struct net_device *dev) |
| 151 | { |
| 152 | struct ifb_private *dp = netdev_priv(dev); |
| 153 | struct net_device_stats *stats = &dp->stats; |
| 154 | int ret = 0; |
| 155 | u32 from = G_TC_FROM(skb->tc_verd); |
| 156 | |
dean gaudet | 3136dcb | 2007-01-01 19:39:09 -0800 | [diff] [blame^] | 157 | stats->rx_packets++; |
| 158 | stats->rx_bytes+=skb->len; |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 159 | |
| 160 | if (!from || !skb->input_dev) { |
| 161 | dropped: |
| 162 | dev_kfree_skb(skb); |
| 163 | stats->rx_dropped++; |
| 164 | return ret; |
| 165 | } else { |
Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 166 | /* |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 167 | * note we could be going |
| 168 | * ingress -> egress or |
| 169 | * egress -> ingress |
| 170 | */ |
| 171 | skb->dev = skb->input_dev; |
| 172 | skb->input_dev = dev; |
| 173 | if (from & AT_INGRESS) { |
| 174 | skb_pull(skb, skb->dev->hard_header_len); |
| 175 | } else { |
| 176 | if (!(from & AT_EGRESS)) { |
| 177 | goto dropped; |
| 178 | } |
| 179 | } |
| 180 | } |
| 181 | |
| 182 | if (skb_queue_len(&dp->rq) >= dev->tx_queue_len) { |
| 183 | netif_stop_queue(dev); |
| 184 | } |
| 185 | |
| 186 | dev->trans_start = jiffies; |
| 187 | skb_queue_tail(&dp->rq, skb); |
| 188 | if (!dp->tasklet_pending) { |
| 189 | dp->tasklet_pending = 1; |
| 190 | tasklet_schedule(&dp->ifb_tasklet); |
| 191 | } |
| 192 | |
| 193 | return ret; |
| 194 | } |
| 195 | |
| 196 | static struct net_device_stats *ifb_get_stats(struct net_device *dev) |
| 197 | { |
| 198 | struct ifb_private *dp = netdev_priv(dev); |
| 199 | struct net_device_stats *stats = &dp->stats; |
| 200 | |
| 201 | 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] | 202 | 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] | 203 | dp->st_rx2tx_tran, dp->st_rxq_notenter, dp->st_rx_frm_egr, |
| 204 | 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] | 205 | |
| 206 | return stats; |
| 207 | } |
| 208 | |
| 209 | static struct net_device **ifbs; |
| 210 | |
| 211 | /* Number of ifb devices to be set up by this module. */ |
| 212 | module_param(numifbs, int, 0); |
| 213 | MODULE_PARM_DESC(numifbs, "Number of ifb devices"); |
| 214 | |
| 215 | static int ifb_close(struct net_device *dev) |
| 216 | { |
| 217 | struct ifb_private *dp = netdev_priv(dev); |
| 218 | |
| 219 | tasklet_kill(&dp->ifb_tasklet); |
| 220 | netif_stop_queue(dev); |
| 221 | skb_queue_purge(&dp->rq); |
| 222 | skb_queue_purge(&dp->tq); |
| 223 | return 0; |
| 224 | } |
| 225 | |
| 226 | static int ifb_open(struct net_device *dev) |
| 227 | { |
| 228 | struct ifb_private *dp = netdev_priv(dev); |
| 229 | |
| 230 | tasklet_init(&dp->ifb_tasklet, ri_tasklet, (unsigned long)dev); |
| 231 | skb_queue_head_init(&dp->rq); |
| 232 | skb_queue_head_init(&dp->tq); |
| 233 | netif_start_queue(dev); |
| 234 | |
| 235 | return 0; |
| 236 | } |
| 237 | |
| 238 | static int __init ifb_init_one(int index) |
| 239 | { |
| 240 | struct net_device *dev_ifb; |
| 241 | int err; |
| 242 | |
| 243 | dev_ifb = alloc_netdev(sizeof(struct ifb_private), |
| 244 | "ifb%d", ifb_setup); |
| 245 | |
| 246 | if (!dev_ifb) |
| 247 | return -ENOMEM; |
| 248 | |
| 249 | if ((err = register_netdev(dev_ifb))) { |
| 250 | free_netdev(dev_ifb); |
| 251 | dev_ifb = NULL; |
| 252 | } else { |
Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 253 | ifbs[index] = dev_ifb; |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 254 | } |
| 255 | |
| 256 | return err; |
| 257 | } |
| 258 | |
| 259 | static void ifb_free_one(int index) |
| 260 | { |
| 261 | unregister_netdev(ifbs[index]); |
| 262 | free_netdev(ifbs[index]); |
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 | { |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 267 | int i, err = 0; |
Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 268 | ifbs = kmalloc(numifbs * sizeof(void *), GFP_KERNEL); |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 269 | if (!ifbs) |
Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 270 | return -ENOMEM; |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 271 | for (i = 0; i < numifbs && !err; i++) |
Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 272 | err = ifb_init_one(i); |
| 273 | if (err) { |
Nicolas Dichtel | 4a9c74e | 2006-07-21 14:56:02 -0700 | [diff] [blame] | 274 | i--; |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 275 | while (--i >= 0) |
| 276 | ifb_free_one(i); |
| 277 | } |
| 278 | |
| 279 | return err; |
Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 280 | } |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 281 | |
| 282 | static void __exit ifb_cleanup_module(void) |
| 283 | { |
| 284 | int i; |
| 285 | |
Jeff Garzik | 6aa20a2 | 2006-09-13 13:24:59 -0400 | [diff] [blame] | 286 | for (i = 0; i < numifbs; i++) |
| 287 | ifb_free_one(i); |
| 288 | kfree(ifbs); |
Jamal Hadi Salim | 253af42 | 2006-01-08 22:34:25 -0800 | [diff] [blame] | 289 | } |
| 290 | |
| 291 | module_init(ifb_init_module); |
| 292 | module_exit(ifb_cleanup_module); |
| 293 | MODULE_LICENSE("GPL"); |
| 294 | MODULE_AUTHOR("Jamal Hadi Salim"); |