linux/drivers/net/ifb.c
Eric W. Biederman 881d966b48 [NET]: Make the device list and device lookups per namespace.
This patch makes most of the generic device layer network
namespace safe.  This patch makes dev_base_head a
network namespace variable, and then it picks up
a few associated variables.  The functions:
dev_getbyhwaddr
dev_getfirsthwbytype
dev_get_by_flags
dev_get_by_name
__dev_get_by_name
dev_get_by_index
__dev_get_by_index
dev_ioctl
dev_ethtool
dev_load
wireless_process_ioctl

were modified to take a network namespace argument, and
deal with it.

vlan_ioctl_set and brioctl_set were modified so their
hooks will receive a network namespace argument.

So basically anthing in the core of the network stack that was
affected to by the change of dev_base was modified to handle
multiple network namespaces.  The rest of the network stack was
simply modified to explicitly use &init_net the initial network
namespace.  This can be fixed when those components of the network
stack are modified to handle multiple network namespaces.

For now the ifindex generator is left global.

Fundametally ifindex numbers are per namespace, or else
we will have corner case problems with migration when
we get that far.

At the same time there are assumptions in the network stack
that the ifindex of a network device won't change.  Making
the ifindex number global seems a good compromise until
the network stack can cope with ifindex changes when
you change namespaces, and the like.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:49:10 -07:00

299 lines
7.1 KiB
C

/* 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 <linux/module.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/init.h>
#include <linux/moduleparam.h>
#include <net/pkt_sched.h>
#include <net/net_namespace.h>
#define TX_TIMEOUT (2*HZ)
#define TX_Q_LIMIT 32
struct ifb_private {
struct net_device_stats stats;
struct tasklet_struct ifb_tasklet;
int tasklet_pending;
/* mostly debug stats leave in for now */
unsigned long st_task_enter; /* tasklet entered */
unsigned long st_txq_refl_try; /* transmit queue refill attempt */
unsigned long st_rxq_enter; /* receive queue entered */
unsigned long st_rx2tx_tran; /* receive to trasmit transfers */
unsigned long st_rxq_notenter; /*receiveQ not entered, resched */
unsigned long st_rx_frm_egr; /* received from egress path */
unsigned long st_rx_frm_ing; /* received from ingress path */
unsigned long st_rxq_check;
unsigned long st_rxq_rsch;
struct sk_buff_head rq;
struct sk_buff_head tq;
};
static int numifbs = 2;
static void ri_tasklet(unsigned long dev);
static int ifb_xmit(struct sk_buff *skb, struct net_device *dev);
static struct net_device_stats *ifb_get_stats(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 net_device_stats *stats = &dp->stats;
struct sk_buff *skb;
dp->st_task_enter++;
if ((skb = skb_peek(&dp->tq)) == NULL) {
dp->st_txq_refl_try++;
if (netif_tx_trylock(_dev)) {
dp->st_rxq_enter++;
while ((skb = skb_dequeue(&dp->rq)) != NULL) {
skb_queue_tail(&dp->tq, skb);
dp->st_rx2tx_tran++;
}
netif_tx_unlock(_dev);
} else {
/* reschedule */
dp->st_rxq_notenter++;
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);
stats->tx_packets++;
stats->tx_bytes +=skb->len;
skb->dev = __dev_get_by_index(&init_net, skb->iif);
if (!skb->dev) {
dev_kfree_skb(skb);
stats->tx_dropped++;
break;
}
skb->iif = _dev->ifindex;
if (from & AT_EGRESS) {
dp->st_rx_frm_egr++;
dev_queue_xmit(skb);
} else if (from & AT_INGRESS) {
dp->st_rx_frm_ing++;
skb_pull(skb, skb->dev->hard_header_len);
netif_rx(skb);
} else
BUG();
}
if (netif_tx_trylock(_dev)) {
dp->st_rxq_check++;
if ((skb = skb_peek(&dp->rq)) == NULL) {
dp->tasklet_pending = 0;
if (netif_queue_stopped(_dev))
netif_wake_queue(_dev);
} else {
dp->st_rxq_rsch++;
netif_tx_unlock(_dev);
goto resched;
}
netif_tx_unlock(_dev);
} else {
resched:
dp->tasklet_pending = 1;
tasklet_schedule(&dp->ifb_tasklet);
}
}
static void ifb_setup(struct net_device *dev)
{
/* Initialize the device structure. */
dev->get_stats = ifb_get_stats;
dev->hard_start_xmit = ifb_xmit;
dev->open = &ifb_open;
dev->stop = &ifb_close;
dev->destructor = free_netdev;
/* Fill in device structure with ethernet-generic values. */
ether_setup(dev);
dev->tx_queue_len = TX_Q_LIMIT;
dev->change_mtu = NULL;
dev->flags |= IFF_NOARP;
dev->flags &= ~IFF_MULTICAST;
SET_MODULE_OWNER(dev);
random_ether_addr(dev->dev_addr);
}
static int ifb_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct ifb_private *dp = netdev_priv(dev);
struct net_device_stats *stats = &dp->stats;
int ret = 0;
u32 from = G_TC_FROM(skb->tc_verd);
stats->rx_packets++;
stats->rx_bytes+=skb->len;
if (!(from & (AT_INGRESS|AT_EGRESS)) || !skb->iif) {
dev_kfree_skb(skb);
stats->rx_dropped++;
return ret;
}
if (skb_queue_len(&dp->rq) >= dev->tx_queue_len) {
netif_stop_queue(dev);
}
dev->trans_start = jiffies;
skb_queue_tail(&dp->rq, skb);
if (!dp->tasklet_pending) {
dp->tasklet_pending = 1;
tasklet_schedule(&dp->ifb_tasklet);
}
return ret;
}
static struct net_device_stats *ifb_get_stats(struct net_device *dev)
{
struct ifb_private *dp = netdev_priv(dev);
struct net_device_stats *stats = &dp->stats;
pr_debug("tasklets stats %ld:%ld:%ld:%ld:%ld:%ld:%ld:%ld:%ld \n",
dp->st_task_enter, dp->st_txq_refl_try, dp->st_rxq_enter,
dp->st_rx2tx_tran, dp->st_rxq_notenter, dp->st_rx_frm_egr,
dp->st_rx_frm_ing, dp->st_rxq_check, dp->st_rxq_rsch);
return stats;
}
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;
int err;
dev_ifb = alloc_netdev(sizeof(struct ifb_private),
"ifb%d", ifb_setup);
if (!dev_ifb)
return -ENOMEM;
err = dev_alloc_name(dev_ifb, dev_ifb->name);
if (err < 0)
goto err;
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);
for (i = 0; i < numifbs && !err; i++)
err = ifb_init_one(i);
if (err)
__rtnl_link_unregister(&ifb_link_ops);
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");