From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Andr=C3=A9=20Fabian=20Silva=20Delgado?= Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- drivers/net/ifb.c | 326 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 326 insertions(+) create mode 100644 drivers/net/ifb.c (limited to 'drivers/net/ifb.c') diff --git a/drivers/net/ifb.c b/drivers/net/ifb.c new file mode 100644 index 000000000..94570aace --- /dev/null +++ b/drivers/net/ifb.c @@ -0,0 +1,326 @@ +/* drivers/net/ifb.c: + + The purpose of this driver is to provide a device that allows + for sharing of resources: + + 1) qdiscs/policies that are per device as opposed to system wide. + ifb allows for a device which can be redirected to thus providing + an impression of sharing. + + 2) Allows for queueing incoming traffic for shaping instead of + dropping. + + The original concept is based on what is known as the IMQ + driver initially written by Martin Devera, later rewritten + by Patrick McHardy and then maintained by Andre Correa. + + You need the tc action mirror or redirect to feed this device + packets. + + This program is free software; you can redistribute it and/or + modify it under the terms of the GNU General Public License + as published by the Free Software Foundation; either version + 2 of the License, or (at your option) any later version. + + Authors: Jamal Hadi Salim (2005) + +*/ + + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define TX_Q_LIMIT 32 +struct ifb_private { + struct tasklet_struct ifb_tasklet; + int tasklet_pending; + + struct u64_stats_sync rsync; + struct sk_buff_head rq; + u64 rx_packets; + u64 rx_bytes; + + struct u64_stats_sync tsync; + struct sk_buff_head tq; + u64 tx_packets; + u64 tx_bytes; +}; + +static int numifbs = 2; + +static void ri_tasklet(unsigned long dev); +static netdev_tx_t ifb_xmit(struct sk_buff *skb, struct net_device *dev); +static int ifb_open(struct net_device *dev); +static int ifb_close(struct net_device *dev); + +static void ri_tasklet(unsigned long dev) +{ + struct net_device *_dev = (struct net_device *)dev; + struct ifb_private *dp = netdev_priv(_dev); + struct netdev_queue *txq; + struct sk_buff *skb; + + txq = netdev_get_tx_queue(_dev, 0); + if ((skb = skb_peek(&dp->tq)) == NULL) { + if (__netif_tx_trylock(txq)) { + skb_queue_splice_tail_init(&dp->rq, &dp->tq); + __netif_tx_unlock(txq); + } else { + /* reschedule */ + goto resched; + } + } + + while ((skb = __skb_dequeue(&dp->tq)) != NULL) { + u32 from = G_TC_FROM(skb->tc_verd); + + skb->tc_verd = 0; + skb->tc_verd = SET_TC_NCLS(skb->tc_verd); + + u64_stats_update_begin(&dp->tsync); + dp->tx_packets++; + dp->tx_bytes += skb->len; + u64_stats_update_end(&dp->tsync); + + rcu_read_lock(); + skb->dev = dev_get_by_index_rcu(dev_net(_dev), skb->skb_iif); + if (!skb->dev) { + rcu_read_unlock(); + dev_kfree_skb(skb); + _dev->stats.tx_dropped++; + if (skb_queue_len(&dp->tq) != 0) + goto resched; + break; + } + rcu_read_unlock(); + skb->skb_iif = _dev->ifindex; + + if (from & AT_EGRESS) { + dev_queue_xmit(skb); + } else if (from & AT_INGRESS) { + skb_pull(skb, skb->mac_len); + netif_receive_skb(skb); + } else + BUG(); + } + + if (__netif_tx_trylock(txq)) { + if ((skb = skb_peek(&dp->rq)) == NULL) { + dp->tasklet_pending = 0; + if (netif_queue_stopped(_dev)) + netif_wake_queue(_dev); + } else { + __netif_tx_unlock(txq); + goto resched; + } + __netif_tx_unlock(txq); + } else { +resched: + dp->tasklet_pending = 1; + tasklet_schedule(&dp->ifb_tasklet); + } + +} + +static struct rtnl_link_stats64 *ifb_stats64(struct net_device *dev, + struct rtnl_link_stats64 *stats) +{ + struct ifb_private *dp = netdev_priv(dev); + unsigned int start; + + do { + start = u64_stats_fetch_begin_irq(&dp->rsync); + stats->rx_packets = dp->rx_packets; + stats->rx_bytes = dp->rx_bytes; + } while (u64_stats_fetch_retry_irq(&dp->rsync, start)); + + do { + start = u64_stats_fetch_begin_irq(&dp->tsync); + + stats->tx_packets = dp->tx_packets; + stats->tx_bytes = dp->tx_bytes; + + } while (u64_stats_fetch_retry_irq(&dp->tsync, start)); + + stats->rx_dropped = dev->stats.rx_dropped; + stats->tx_dropped = dev->stats.tx_dropped; + + return stats; +} + + +static const struct net_device_ops ifb_netdev_ops = { + .ndo_open = ifb_open, + .ndo_stop = ifb_close, + .ndo_get_stats64 = ifb_stats64, + .ndo_start_xmit = ifb_xmit, + .ndo_validate_addr = eth_validate_addr, +}; + +#define IFB_FEATURES (NETIF_F_HW_CSUM | NETIF_F_SG | NETIF_F_FRAGLIST | \ + NETIF_F_TSO_ECN | NETIF_F_TSO | NETIF_F_TSO6 | \ + NETIF_F_HIGHDMA | NETIF_F_HW_VLAN_CTAG_TX | \ + NETIF_F_HW_VLAN_STAG_TX) + +static void ifb_setup(struct net_device *dev) +{ + /* Initialize the device structure. */ + dev->destructor = free_netdev; + dev->netdev_ops = &ifb_netdev_ops; + + /* Fill in device structure with ethernet-generic values. */ + ether_setup(dev); + dev->tx_queue_len = TX_Q_LIMIT; + + dev->features |= IFB_FEATURES; + dev->vlan_features |= IFB_FEATURES & ~(NETIF_F_HW_VLAN_CTAG_TX | + NETIF_F_HW_VLAN_STAG_TX); + + dev->flags |= IFF_NOARP; + dev->flags &= ~IFF_MULTICAST; + dev->priv_flags &= ~IFF_TX_SKB_SHARING; + netif_keep_dst(dev); + eth_hw_addr_random(dev); +} + +static netdev_tx_t ifb_xmit(struct sk_buff *skb, struct net_device *dev) +{ + struct ifb_private *dp = netdev_priv(dev); + u32 from = G_TC_FROM(skb->tc_verd); + + u64_stats_update_begin(&dp->rsync); + dp->rx_packets++; + dp->rx_bytes += skb->len; + u64_stats_update_end(&dp->rsync); + + if (!(from & (AT_INGRESS|AT_EGRESS)) || !skb->skb_iif) { + dev_kfree_skb(skb); + dev->stats.rx_dropped++; + return NETDEV_TX_OK; + } + + if (skb_queue_len(&dp->rq) >= dev->tx_queue_len) { + netif_stop_queue(dev); + } + + __skb_queue_tail(&dp->rq, skb); + if (!dp->tasklet_pending) { + dp->tasklet_pending = 1; + tasklet_schedule(&dp->ifb_tasklet); + } + + return NETDEV_TX_OK; +} + +static int ifb_close(struct net_device *dev) +{ + struct ifb_private *dp = netdev_priv(dev); + + tasklet_kill(&dp->ifb_tasklet); + netif_stop_queue(dev); + __skb_queue_purge(&dp->rq); + __skb_queue_purge(&dp->tq); + return 0; +} + +static int ifb_open(struct net_device *dev) +{ + struct ifb_private *dp = netdev_priv(dev); + + tasklet_init(&dp->ifb_tasklet, ri_tasklet, (unsigned long)dev); + __skb_queue_head_init(&dp->rq); + __skb_queue_head_init(&dp->tq); + netif_start_queue(dev); + + return 0; +} + +static int ifb_validate(struct nlattr *tb[], struct nlattr *data[]) +{ + if (tb[IFLA_ADDRESS]) { + if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) + return -EINVAL; + if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) + return -EADDRNOTAVAIL; + } + return 0; +} + +static struct rtnl_link_ops ifb_link_ops __read_mostly = { + .kind = "ifb", + .priv_size = sizeof(struct ifb_private), + .setup = ifb_setup, + .validate = ifb_validate, +}; + +/* Number of ifb devices to be set up by this module. */ +module_param(numifbs, int, 0); +MODULE_PARM_DESC(numifbs, "Number of ifb devices"); + +static int __init ifb_init_one(int index) +{ + struct net_device *dev_ifb; + struct ifb_private *dp; + int err; + + dev_ifb = alloc_netdev(sizeof(struct ifb_private), "ifb%d", + NET_NAME_UNKNOWN, ifb_setup); + + if (!dev_ifb) + return -ENOMEM; + + dp = netdev_priv(dev_ifb); + u64_stats_init(&dp->rsync); + u64_stats_init(&dp->tsync); + + dev_ifb->rtnl_link_ops = &ifb_link_ops; + err = register_netdevice(dev_ifb); + if (err < 0) + goto err; + + return 0; + +err: + free_netdev(dev_ifb); + return err; +} + +static int __init ifb_init_module(void) +{ + int i, err; + + rtnl_lock(); + err = __rtnl_link_register(&ifb_link_ops); + if (err < 0) + goto out; + + for (i = 0; i < numifbs && !err; i++) { + err = ifb_init_one(i); + cond_resched(); + } + if (err) + __rtnl_link_unregister(&ifb_link_ops); + +out: + rtnl_unlock(); + + return err; +} + +static void __exit ifb_cleanup_module(void) +{ + rtnl_link_unregister(&ifb_link_ops); +} + +module_init(ifb_init_module); +module_exit(ifb_cleanup_module); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Jamal Hadi Salim"); +MODULE_ALIAS_RTNL_LINK("ifb"); -- cgit v1.2.3