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path: root/drivers/net/tun.c
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Diffstat (limited to 'drivers/net/tun.c')
-rw-r--r--drivers/net/tun.c86
1 files changed, 63 insertions, 23 deletions
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 40b426edc9e6..255a9f574869 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -138,6 +138,8 @@ struct tun_file {
/* only used for fasnyc */
unsigned int flags;
u16 queue_index;
+ struct list_head next;
+ struct tun_struct *detached;
};
struct tun_flow_entry {
@@ -182,6 +184,8 @@ struct tun_struct {
struct hlist_head flows[TUN_NUM_FLOW_ENTRIES];
struct timer_list flow_gc_timer;
unsigned long ageing_time;
+ unsigned int numdisabled;
+ struct list_head disabled;
};
static inline u32 tun_hashfn(u32 rxhash)
@@ -385,6 +389,23 @@ static void tun_set_real_num_queues(struct tun_struct *tun)
netif_set_real_num_rx_queues(tun->dev, tun->numqueues);
}
+static void tun_disable_queue(struct tun_struct *tun, struct tun_file *tfile)
+{
+ tfile->detached = tun;
+ list_add_tail(&tfile->next, &tun->disabled);
+ ++tun->numdisabled;
+}
+
+struct tun_struct *tun_enable_queue(struct tun_file *tfile)
+{
+ struct tun_struct *tun = tfile->detached;
+
+ tfile->detached = NULL;
+ list_del_init(&tfile->next);
+ --tun->numdisabled;
+ return tun;
+}
+
static void __tun_detach(struct tun_file *tfile, bool clean)
{
struct tun_file *ntfile;
@@ -406,20 +427,25 @@ static void __tun_detach(struct tun_file *tfile, bool clean)
ntfile->queue_index = index;
--tun->numqueues;
- sock_put(&tfile->sk);
+ if (clean)
+ sock_put(&tfile->sk);
+ else
+ tun_disable_queue(tun, tfile);
synchronize_net();
tun_flow_delete_by_queue(tun, tun->numqueues + 1);
/* Drop read queue */
skb_queue_purge(&tfile->sk.sk_receive_queue);
tun_set_real_num_queues(tun);
-
- if (tun->numqueues == 0 && !(tun->flags & TUN_PERSIST))
- if (dev->reg_state == NETREG_REGISTERED)
- unregister_netdevice(dev);
- }
+ } else if (tfile->detached && clean)
+ tun = tun_enable_queue(tfile);
if (clean) {
+ if (tun && tun->numqueues == 0 && tun->numdisabled == 0 &&
+ !(tun->flags & TUN_PERSIST))
+ if (tun->dev->reg_state == NETREG_REGISTERED)
+ unregister_netdevice(tun->dev);
+
BUG_ON(!test_bit(SOCK_EXTERNALLY_ALLOCATED,
&tfile->socket.flags));
sk_release_kernel(&tfile->sk);
@@ -436,7 +462,7 @@ static void tun_detach(struct tun_file *tfile, bool clean)
static void tun_detach_all(struct net_device *dev)
{
struct tun_struct *tun = netdev_priv(dev);
- struct tun_file *tfile;
+ struct tun_file *tfile, *tmp;
int i, n = tun->numqueues;
for (i = 0; i < n; i++) {
@@ -457,6 +483,12 @@ static void tun_detach_all(struct net_device *dev)
skb_queue_purge(&tfile->sk.sk_receive_queue);
sock_put(&tfile->sk);
}
+ list_for_each_entry_safe(tfile, tmp, &tun->disabled, next) {
+ tun_enable_queue(tfile);
+ skb_queue_purge(&tfile->sk.sk_receive_queue);
+ sock_put(&tfile->sk);
+ }
+ BUG_ON(tun->numdisabled != 0);
}
static int tun_attach(struct tun_struct *tun, struct file *file)
@@ -473,7 +505,8 @@ static int tun_attach(struct tun_struct *tun, struct file *file)
goto out;
err = -E2BIG;
- if (tun->numqueues == MAX_TAP_QUEUES)
+ if (!tfile->detached &&
+ tun->numqueues + tun->numdisabled == MAX_TAP_QUEUES)
goto out;
err = 0;
@@ -487,9 +520,13 @@ static int tun_attach(struct tun_struct *tun, struct file *file)
tfile->queue_index = tun->numqueues;
rcu_assign_pointer(tfile->tun, tun);
rcu_assign_pointer(tun->tfiles[tun->numqueues], tfile);
- sock_hold(&tfile->sk);
tun->numqueues++;
+ if (tfile->detached)
+ tun_enable_queue(tfile);
+ else
+ sock_hold(&tfile->sk);
+
tun_set_real_num_queues(tun);
/* device is allowed to go away first, so no need to hold extra
@@ -1349,6 +1386,7 @@ static void tun_free_netdev(struct net_device *dev)
{
struct tun_struct *tun = netdev_priv(dev);
+ BUG_ON(!(list_empty(&tun->disabled)));
tun_flow_uninit(tun);
free_netdev(dev);
}
@@ -1543,6 +1581,10 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
err = tun_attach(tun, file);
if (err < 0)
return err;
+
+ if (tun->flags & TUN_TAP_MQ &&
+ (tun->numqueues + tun->numdisabled > 1))
+ return err;
}
else {
char *name;
@@ -1601,6 +1643,7 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
TUN_USER_FEATURES;
dev->features = dev->hw_features;
+ INIT_LIST_HEAD(&tun->disabled);
err = tun_attach(tun, file);
if (err < 0)
goto err_free_dev;
@@ -1755,32 +1798,28 @@ static int tun_set_queue(struct file *file, struct ifreq *ifr)
{
struct tun_file *tfile = file->private_data;
struct tun_struct *tun;
- struct net_device *dev;
int ret = 0;
rtnl_lock();
if (ifr->ifr_flags & IFF_ATTACH_QUEUE) {
- dev = __dev_get_by_name(tfile->net, ifr->ifr_name);
- if (!dev) {
- ret = -EINVAL;
- goto unlock;
- }
-
- tun = netdev_priv(dev);
- if (dev->netdev_ops != &tap_netdev_ops &&
- dev->netdev_ops != &tun_netdev_ops)
+ tun = tfile->detached;
+ if (!tun)
ret = -EINVAL;
else if (tun_not_capable(tun))
ret = -EPERM;
else
ret = tun_attach(tun, file);
- } else if (ifr->ifr_flags & IFF_DETACH_QUEUE)
- __tun_detach(tfile, false);
- else
+ } else if (ifr->ifr_flags & IFF_DETACH_QUEUE) {
+ tun = rcu_dereference_protected(tfile->tun,
+ lockdep_rtnl_is_held());
+ if (!tun || !(tun->flags & TUN_TAP_MQ))
+ ret = -EINVAL;
+ else
+ __tun_detach(tfile, false);
+ } else
ret = -EINVAL;
-unlock:
rtnl_unlock();
return ret;
}
@@ -2092,6 +2131,7 @@ static int tun_chr_open(struct inode *inode, struct file * file)
file->private_data = tfile;
set_bit(SOCK_EXTERNALLY_ALLOCATED, &tfile->socket.flags);
+ INIT_LIST_HEAD(&tfile->next);
return 0;
}
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-22 17:21:53 +0300