macvtap: introduce macvtap_get_vlan()

Factor out the device holding logic to a macvtap_get_vlan(), this will be also
used by multiqueue API.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 20 insertions, 7 deletions

diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c
index 8949631c080c..d18130b3fe0d 100644
--- a/drivers/net/macvtap.c
+++ b/drivers/net/macvtap.c
@@ -893,6 +893,24 @@ out:
         return ret;
 }
 
+static struct macvlan_dev *macvtap_get_vlan(struct macvtap_queue *q)
+{
+        struct macvlan_dev *vlan;
+
+        rcu_read_lock_bh();
+        vlan = rcu_dereference_bh(q->vlan);
+        if (vlan)
+                dev_hold(vlan->dev);
+        rcu_read_unlock_bh();
+
+        return vlan;
+}
+
+static void macvtap_put_vlan(struct macvlan_dev *vlan)
+{
+        dev_put(vlan->dev);
+}
+
 /*
  * provide compatibility with generic tun/tap interface
  */
@@ -924,12 +942,7 @@ static long macvtap_ioctl(struct file *file, unsigned int cmd,
                 return ret;
 
         case TUNGETIFF:
-                rcu_read_lock_bh();
-                vlan = rcu_dereference_bh(q->vlan);
-                if (vlan)
-                        dev_hold(vlan->dev);
-                rcu_read_unlock_bh();
-
+                vlan = macvtap_get_vlan(q);
                 if (!vlan)
                         return -ENOLINK;
 
@@ -937,7 +950,7 @@ static long macvtap_ioctl(struct file *file, unsigned int cmd,
                 if (copy_to_user(&ifr->ifr_name, vlan->dev->name, IFNAMSIZ) ||
                     put_user(q->flags, &ifr->ifr_flags))
                         ret = -EFAULT;
-                dev_put(vlan->dev);
+                macvtap_put_vlan(vlan);
                 return ret;
 
         case TUNGETFEATURES: