From 74a3e5a71c9b54c63bff978e9cafbcef67600f0b Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Tue, 20 Jan 2009 10:56:20 +0000 Subject: tun: Remove unnecessary tun_get_by_name Currently the tun driver keeps a private list of tun devices for what appears to be a small gain in performance when reconnecting a file descriptor to an existing tun or tap device. So simplify the code by removing it. Signed-off-by: Eric W. Biederman Signed-off-by: David S. Miller --- drivers/net/tun.c | 74 ++++++++++++++----------------------------------------- 1 file changed, 19 insertions(+), 55 deletions(-) (limited to 'drivers/net') diff --git a/drivers/net/tun.c b/drivers/net/tun.c index d7b81e4fdd5..17923a50853 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -88,7 +88,6 @@ struct tap_filter { }; struct tun_struct { - struct list_head list; unsigned int flags; int attached; uid_t owner; @@ -213,11 +212,6 @@ static int check_filter(struct tap_filter *filter, const struct sk_buff *skb) /* Network device part of the driver */ -static int tun_net_id; -struct tun_net { - struct list_head dev_list; -}; - static const struct ethtool_ops tun_ethtool_ops; /* Net device open. */ @@ -697,30 +691,22 @@ static void tun_setup(struct net_device *dev) dev->features |= NETIF_F_NETNS_LOCAL; } -static struct tun_struct *tun_get_by_name(struct tun_net *tn, const char *name) -{ - struct tun_struct *tun; - - ASSERT_RTNL(); - list_for_each_entry(tun, &tn->dev_list, list) { - if (!strncmp(tun->dev->name, name, IFNAMSIZ)) - return tun; - } - - return NULL; -} - static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) { - struct tun_net *tn; struct tun_struct *tun; struct net_device *dev; const struct cred *cred = current_cred(); int err; - tn = net_generic(net, tun_net_id); - tun = tun_get_by_name(tn, ifr->ifr_name); - if (tun) { + dev = __dev_get_by_name(net, ifr->ifr_name); + if (dev) { + if ((ifr->ifr_flags & IFF_TUN) && dev->netdev_ops == &tun_netdev_ops) + tun = netdev_priv(dev); + else if ((ifr->ifr_flags & IFF_TAP) && dev->netdev_ops == &tap_netdev_ops) + tun = netdev_priv(dev); + else + return -EINVAL; + if (tun->attached) return -EBUSY; @@ -733,8 +719,6 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) return -EPERM; } } - else if (__dev_get_by_name(net, ifr->ifr_name)) - return -EINVAL; else { char *name; unsigned long flags = 0; @@ -782,8 +766,6 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) err = register_netdevice(tun->dev); if (err < 0) goto err_free_dev; - - list_add(&tun->list, &tn->dev_list); } DBG(KERN_INFO "%s: tun_set_iff\n", tun->dev->name); @@ -1095,10 +1077,8 @@ static int tun_chr_close(struct inode *inode, struct file *file) /* Drop read queue */ skb_queue_purge(&tun->readq); - if (!(tun->flags & TUN_PERSIST)) { - list_del(&tun->list); + if (!(tun->flags & TUN_PERSIST)) unregister_netdevice(tun->dev); - } rtnl_unlock(); @@ -1212,37 +1192,21 @@ static const struct ethtool_ops tun_ethtool_ops = { static int tun_init_net(struct net *net) { - struct tun_net *tn; - - tn = kmalloc(sizeof(*tn), GFP_KERNEL); - if (tn == NULL) - return -ENOMEM; - - INIT_LIST_HEAD(&tn->dev_list); - - if (net_assign_generic(net, tun_net_id, tn)) { - kfree(tn); - return -ENOMEM; - } - return 0; } static void tun_exit_net(struct net *net) { - struct tun_net *tn; - struct tun_struct *tun, *nxt; - - tn = net_generic(net, tun_net_id); + struct net_device *dev, *next; rtnl_lock(); - list_for_each_entry_safe(tun, nxt, &tn->dev_list, list) { - DBG(KERN_INFO "%s cleaned up\n", tun->dev->name); - unregister_netdevice(tun->dev); + for_each_netdev_safe(net, dev, next) { + if (dev->ethtool_ops != &tun_ethtool_ops) + continue; + DBG(KERN_INFO "%s cleaned up\n", dev->name); + unregister_netdevice(dev); } rtnl_unlock(); - - kfree(tn); } static struct pernet_operations tun_net_ops = { @@ -1257,7 +1221,7 @@ static int __init tun_init(void) printk(KERN_INFO "tun: %s, %s\n", DRV_DESCRIPTION, DRV_VERSION); printk(KERN_INFO "tun: %s\n", DRV_COPYRIGHT); - ret = register_pernet_gen_device(&tun_net_id, &tun_net_ops); + ret = register_pernet_device(&tun_net_ops); if (ret) { printk(KERN_ERR "tun: Can't register pernet ops\n"); goto err_pernet; @@ -1271,7 +1235,7 @@ static int __init tun_init(void) return 0; err_misc: - unregister_pernet_gen_device(tun_net_id, &tun_net_ops); + unregister_pernet_device(&tun_net_ops); err_pernet: return ret; } @@ -1279,7 +1243,7 @@ err_pernet: static void tun_cleanup(void) { misc_deregister(&tun_miscdev); - unregister_pernet_gen_device(tun_net_id, &tun_net_ops); + unregister_pernet_device(&tun_net_ops); } module_init(tun_init); -- cgit v1.2.3-70-g09d2