#include <linux/virtio_net.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>
+#include <net/rtnetlink.h>
#include <asm/system.h>
#include <asm/uaccess.h>
};
struct tun_file {
+ atomic_t count;
struct tun_struct *tun;
struct net *net;
+ wait_queue_head_t read_wait;
};
struct tun_struct {
uid_t owner;
gid_t group;
- wait_queue_head_t read_wait;
struct sk_buff_head readq;
struct net_device *dev;
err = 0;
tfile->tun = tun;
tun->tfile = tfile;
+ dev_hold(tun->dev);
+ atomic_inc(&tfile->count);
out:
netif_tx_unlock_bh(tun->dev);
/* Drop read queue */
skb_queue_purge(&tun->readq);
+
+ /* Drop the extra count on the net device */
+ dev_put(tun->dev);
+}
+
+static void tun_detach(struct tun_struct *tun)
+{
+ rtnl_lock();
+ __tun_detach(tun);
+ rtnl_unlock();
}
static struct tun_struct *__tun_get(struct tun_file *tfile)
{
- return tfile->tun;
+ struct tun_struct *tun = NULL;
+
+ if (atomic_inc_not_zero(&tfile->count))
+ tun = tfile->tun;
+
+ return tun;
}
static struct tun_struct *tun_get(struct file *file)
static void tun_put(struct tun_struct *tun)
{
- /* Noop for now */
+ struct tun_file *tfile = tun->tfile;
+
+ if (atomic_dec_and_test(&tfile->count))
+ tun_detach(tfile->tun);
}
/* TAP filterting */
static const struct ethtool_ops tun_ethtool_ops;
+/* Net device detach from fd. */
+static void tun_net_uninit(struct net_device *dev)
+{
+ struct tun_struct *tun = netdev_priv(dev);
+ struct tun_file *tfile = tun->tfile;
+
+ /* Inform the methods they need to stop using the dev.
+ */
+ if (tfile) {
+ wake_up_all(&tfile->read_wait);
+ if (atomic_dec_and_test(&tfile->count))
+ __tun_detach(tun);
+ }
+}
+
/* Net device open. */
static int tun_net_open(struct net_device *dev)
{
/* Notify and wake up reader process */
if (tun->flags & TUN_FASYNC)
kill_fasync(&tun->fasync, SIGIO, POLL_IN);
- wake_up_interruptible(&tun->read_wait);
+ wake_up_interruptible(&tun->tfile->read_wait);
return 0;
drop:
}
static const struct net_device_ops tun_netdev_ops = {
+ .ndo_uninit = tun_net_uninit,
.ndo_open = tun_net_open,
.ndo_stop = tun_net_close,
.ndo_start_xmit = tun_net_xmit,
};
static const struct net_device_ops tap_netdev_ops = {
+ .ndo_uninit = tun_net_uninit,
.ndo_open = tun_net_open,
.ndo_stop = tun_net_close,
.ndo_start_xmit = tun_net_xmit,
/* Poll */
static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
{
- struct tun_struct *tun = tun_get(file);
+ struct tun_file *tfile = file->private_data;
+ struct tun_struct *tun = __tun_get(tfile);
unsigned int mask = POLLOUT | POLLWRNORM;
if (!tun)
DBG(KERN_INFO "%s: tun_chr_poll\n", tun->dev->name);
- poll_wait(file, &tun->read_wait, wait);
+ poll_wait(file, &tfile->read_wait, wait);
if (!skb_queue_empty(&tun->readq))
mask |= POLLIN | POLLRDNORM;
+ if (tun->dev->reg_state != NETREG_REGISTERED)
+ mask = POLLERR;
+
tun_put(tun);
return mask;
}
unsigned long count, loff_t pos)
{
struct file *file = iocb->ki_filp;
- struct tun_struct *tun = tun_get(file);
+ struct tun_file *tfile = file->private_data;
+ struct tun_struct *tun = __tun_get(tfile);
DECLARE_WAITQUEUE(wait, current);
struct sk_buff *skb;
ssize_t len, ret = 0;
goto out;
}
- add_wait_queue(&tun->read_wait, &wait);
+ add_wait_queue(&tfile->read_wait, &wait);
while (len) {
current->state = TASK_INTERRUPTIBLE;
ret = -ERESTARTSYS;
break;
}
+ if (tun->dev->reg_state != NETREG_REGISTERED) {
+ ret = -EIO;
+ break;
+ }
/* Nothing to read, let's sleep */
schedule();
}
current->state = TASK_RUNNING;
- remove_wait_queue(&tun->read_wait, &wait);
+ remove_wait_queue(&tfile->read_wait, &wait);
out:
tun_put(tun);
struct tun_struct *tun = netdev_priv(dev);
skb_queue_head_init(&tun->readq);
- init_waitqueue_head(&tun->read_wait);
tun->owner = -1;
tun->group = -1;
dev->ethtool_ops = &tun_ethtool_ops;
dev->destructor = free_netdev;
- dev->features |= NETIF_F_NETNS_LOCAL;
}
+/* Trivial set of netlink ops to allow deleting tun or tap
+ * device with netlink.
+ */
+static int tun_validate(struct nlattr *tb[], struct nlattr *data[])
+{
+ return -EINVAL;
+}
+
+static struct rtnl_link_ops tun_link_ops __read_mostly = {
+ .kind = DRV_NAME,
+ .priv_size = sizeof(struct tun_struct),
+ .setup = tun_setup,
+ .validate = tun_validate,
+};
+
+
static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
{
struct tun_struct *tun;
return -ENOMEM;
dev_net_set(dev, net);
+ dev->rtnl_link_ops = &tun_link_ops;
tun = netdev_priv(dev);
tun->dev = dev;
tfile = kmalloc(sizeof(*tfile), GFP_KERNEL);
if (!tfile)
return -ENOMEM;
+ atomic_set(&tfile->count, 0);
tfile->tun = NULL;
tfile->net = get_net(current->nsproxy->net_ns);
+ init_waitqueue_head(&tfile->read_wait);
file->private_data = tfile;
return 0;
}
.set_rx_csum = tun_set_rx_csum
};
-static int tun_init_net(struct net *net)
-{
- return 0;
-}
-
-static void tun_exit_net(struct net *net)
-{
- struct net_device *dev, *next;
-
- rtnl_lock();
- 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();
-}
-
-static struct pernet_operations tun_net_ops = {
- .init = tun_init_net,
- .exit = tun_exit_net,
-};
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_device(&tun_net_ops);
+ ret = rtnl_link_register(&tun_link_ops);
if (ret) {
- printk(KERN_ERR "tun: Can't register pernet ops\n");
- goto err_pernet;
+ printk(KERN_ERR "tun: Can't register link_ops\n");
+ goto err_linkops;
}
ret = misc_register(&tun_miscdev);
printk(KERN_ERR "tun: Can't register misc device %d\n", TUN_MINOR);
goto err_misc;
}
- return 0;
-
+ return 0;
err_misc:
- unregister_pernet_device(&tun_net_ops);
-err_pernet:
+ rtnl_link_unregister(&tun_link_ops);
+err_linkops:
return ret;
}
static void tun_cleanup(void)
{
misc_deregister(&tun_miscdev);
- unregister_pernet_device(&tun_net_ops);
+ rtnl_link_unregister(&tun_link_ops);
}
module_init(tun_init);
projects / mirror_ubuntu-bionic-kernel.git / blobdiff