openvswitch: Simplify datapath locking.

[deliverable/linux.git] / net / openvswitch / vport.c

diff --git a/net/openvswitch/vport.c b/net/openvswitch/vport.c
index f6b8132ce4cb7380a6bca860b4e50a2aa6756772..c90d856d441c26297ae1c768ab82d309f7e11477 100644 (file)
--- a/net/openvswitch/vport.c
+++ b/net/openvswitch/vport.c
@@ -40,7 +40,7 @@ static const struct vport_ops *vport_ops_list[] = {
        &ovs_internal_vport_ops,
 };
 
-/* Protected by RCU read lock for reading, RTNL lock for writing. */
+/* Protected by RCU read lock for reading, ovs_mutex for writing. */
 static struct hlist_head *dev_table;
 #define VPORT_HASH_BUCKETS 1024
 
@@ -80,7 +80,7 @@ static struct hlist_head *hash_bucket(struct net *net, const char *name)
  *
  * @name: name of port to find
  *
- * Must be called with RTNL or RCU read lock.
+ * Must be called with ovs or RCU read lock.
  */
 struct vport *ovs_vport_locate(struct net *net, const char *name)
 {
@@ -161,7 +161,7 @@ void ovs_vport_free(struct vport *vport)
  * @parms: Information about new vport.
  *
  * Creates a new vport with the specified configuration (which is dependent on
- * device type).  RTNL lock must be held.
+ * device type).  ovs_mutex must be held.
  */
 struct vport *ovs_vport_add(const struct vport_parms *parms)
 {
@@ -169,8 +169,6 @@ struct vport *ovs_vport_add(const struct vport_parms *parms)
        int err = 0;
        int i;
 
-       ASSERT_RTNL();
-
        for (i = 0; i < ARRAY_SIZE(vport_ops_list); i++) {
                if (vport_ops_list[i]->type == parms->type) {
                        struct hlist_head *bucket;
@@ -201,12 +199,10 @@ out:
  * @port: New configuration.
  *
  * Modifies an existing device with the specified configuration (which is
- * dependent on device type).  RTNL lock must be held.
+ * dependent on device type).  ovs_mutex must be held.
  */
 int ovs_vport_set_options(struct vport *vport, struct nlattr *options)
 {
-       ASSERT_RTNL();
-
        if (!vport->ops->set_options)
                return -EOPNOTSUPP;
        return vport->ops->set_options(vport, options);
@@ -218,11 +214,11 @@ int ovs_vport_set_options(struct vport *vport, struct nlattr *options)
  * @vport: vport to delete.
  *
  * Detaches @vport from its datapath and destroys it.  It is possible to fail
- * for reasons such as lack of memory.  RTNL lock must be held.
+ * for reasons such as lack of memory.  ovs_mutex must be held.
  */
 void ovs_vport_del(struct vport *vport)
 {
-       ASSERT_RTNL();
+       ASSERT_OVSL();
 
        hlist_del_rcu(&vport->hash_node);
 
@@ -237,7 +233,7 @@ void ovs_vport_del(struct vport *vport)
  *
  * Retrieves transmit, receive, and error stats for the given device.
  *
- * Must be called with RTNL lock or rcu_read_lock.
+ * Must be called with ovs_mutex or rcu_read_lock.
  */
 void ovs_vport_get_stats(struct vport *vport, struct ovs_vport_stats *stats)
 {
@@ -296,22 +292,24 @@ void ovs_vport_get_stats(struct vport *vport, struct ovs_vport_stats *stats)
  * negative error code if a real error occurred.  If an error occurs, @skb is
  * left unmodified.
  *
- * Must be called with RTNL lock or rcu_read_lock.
+ * Must be called with ovs_mutex or rcu_read_lock.
  */
 int ovs_vport_get_options(const struct vport *vport, struct sk_buff *skb)
 {
        struct nlattr *nla;
+       int err;
+
+       if (!vport->ops->get_options)
+               return 0;
 
        nla = nla_nest_start(skb, OVS_VPORT_ATTR_OPTIONS);
        if (!nla)
                return -EMSGSIZE;
 
-       if (vport->ops->get_options) {
-               int err = vport->ops->get_options(vport, skb);
-               if (err) {
-                       nla_nest_cancel(skb, nla);
-                       return err;
-               }
+       err = vport->ops->get_options(vport, skb);
+       if (err) {
+               nla_nest_cancel(skb, nla);
+               return err;
        }
 
        nla_nest_end(skb, nla);
@@ -346,7 +344,7 @@ void ovs_vport_receive(struct vport *vport, struct sk_buff *skb)
  * @vport: vport on which to send the packet
  * @skb: skb to send
  *
- * Sends the given packet and returns the length of data sent.  Either RTNL
+ * Sends the given packet and returns the length of data sent.  Either ovs
  * lock or rcu_read_lock must be held.
  */
 int ovs_vport_send(struct vport *vport, struct sk_buff *skb)