Re: [B.A.T.M.A.N.] [PATCHv5 1/2] batman-adv: add per VLAN interface attribute framework

Re: [B.A.T.M.A.N.] [PATCHv5 1/2] batman-adv: add per VLAN interface attribute framework

[Marek Lindner]

On Thursday, June 13, 2013 02:04:19 Antonio Quartulli wrote:
> --- a/hard-interface.c
> +++ b/hard-interface.c
> @@ -643,6 +643,8 @@ static int batadv_hard_if_event(struct notifier_block
> *this,
> 
>  	if (batadv_softif_is_valid(net_dev) && event == NETDEV_REGISTER) {
>  		batadv_sysfs_add_meshif(net_dev);
> +		bat_priv = netdev_priv(net_dev);
> +		batadv_softif_create_vlan(bat_priv, BATADV_NO_FLAGS);
>  		return NOTIFY_DONE;
>  	}

When is this entry ever removed ? Did you try to rmmod the module with these 
patches enabled ?


> +       /* explicitly remove the associated TT local entry because it is 
marked
> +        * with the NOPURGE flag
> +        */
> +       batadv_tt_local_remove(bat_priv, dev->dev_addr, vid,
> +                              "vlan interface destroyed", false);

Curious. In batadv_interface_add_vid() you force the BATADV_VLAN_HAS_TAG tag 
onto each batadv_tt_local_add() call but on removal we don't have the flag 
set. Are you certain that is correct ?


> @@ -613,6 +632,8 @@ struct batadv_priv {
>  	struct work_struct cleanup_work;
>  	struct batadv_hard_iface __rcu *primary_if;  /* rcu protected pointer */
>  	struct batadv_algo_ops *bat_algo_ops;
> +	struct list_head softif_vlan_list;
> +	spinlock_t softif_vlan_list_lock; /* protects softif_vlan_list */
>  #ifdef CONFIG_BATMAN_ADV_BLA
>  	struct batadv_priv_bla bla;
>  #endif

Why do we need a full blown list ? Isn't hlist sufficient ?

Cheers,
Marek

[B.A.T.M.A.N.] [PATCHv5 1/2] batman-adv: add per VLAN interface attribute framework

[Antonio Quartulli]

From: Antonio Quartulli <antonio@open-mesh.com>

Since batman-adv is now fully VLAN-aware, a proper framework
able to handle per-vlan-interface attributes is needed.

Those attributes will affect the associated VLAN interface
only, rather than the real soft_iface (which would result
in every vlan interface having the same attribute
configuration)

To make the code simpler and easier to extend, attributes
associated to the standalone soft_iface are now treated
like belonging to yet another vlan having a special vid.
This vid is different from the others because it is made up
by all zeros and the VLAN_HAS_TAG bit is not set.

Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
---


v5:
- tt-vlan patchset has been divided in several small patchsets (this is the
  first one)
- change about bat0 being treated like another vlan has been merged in this
  patch
- patch anticipating sysfs creation has been dropped. It could lead to race
  conditions




 compat.c         |   9 ++++
 compat.h         |  24 +++++++++
 hard-interface.c |   2 +
 main.c           |   5 +-
 soft-interface.c | 145 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 soft-interface.h |   1 +
 types.h          |  21 ++++++++
 7 files changed, 204 insertions(+), 3 deletions(-)

diff --git a/compat.c b/compat.c
index da556a4..0a98fb7 100644
--- a/compat.c
+++ b/compat.c
@@ -27,6 +27,15 @@
 
 #if LINUX_VERSION_CODE < KERNEL_VERSION(3, 0, 0)
 
+void batadv_free_rcu_softif_vlan(struct rcu_head *rcu)
+{
+	struct batadv_softif_vlan *vlan;
+
+	vlan = container_of(rcu, struct batadv_softif_vlan, rcu);
+
+	kfree(vlan);
+}
+
 void batadv_free_rcu_tt_global_entry(struct rcu_head *rcu)
 {
 	struct batadv_tt_global_entry *global;
diff --git a/compat.h b/compat.h
index dbf1926..1ee0467 100644
--- a/compat.h
+++ b/compat.h
@@ -182,6 +182,7 @@ static const struct { \
 #define kfree_rcu(ptr, rcu_head) call_rcu(&ptr->rcu_head, batadv_free_rcu_##ptr)
 #define vlan_insert_tag(skb, proto, vid) __vlan_put_tag(skb, vid)
 
+void batadv_free_rcu_softif_vlan(struct rcu_head *rcu);
 void batadv_free_rcu_tt_global_entry(struct rcu_head *rcu);
 void batadv_free_rcu_gw_node(struct rcu_head *rcu);
 void batadv_free_rcu_neigh_node(struct rcu_head *rcu);
@@ -300,6 +301,29 @@ static int __batadv_interface_set_mac_addr(x, y)
 #include <linux/if_vlan.h>
 #define vlan_insert_tag(skb, proto, vid) vlan_insert_tag(skb, vid)
 
+#define NETIF_F_HW_VLAN_CTAG_FILTER NETIF_F_HW_VLAN_FILTER
+
+#define batadv_interface_add_vid(x, y, z) \
+__batadv_interface_add_vid(struct net_device *dev, __be16 proto,\
+			   unsigned short vid);\
+static int batadv_interface_add_vid(struct net_device *dev, unsigned short vid)\
+{\
+	return __batadv_interface_add_vid(dev, htons(ETH_P_8021Q), vid);\
+} \
+static int __batadv_interface_add_vid(struct net_device *dev, __be16 proto,\
+				      unsigned short vid)
+
+#define batadv_interface_kill_vid(x, y, z) \
+__batadv_interface_kill_vid(struct net_device *dev, __be16 proto,\
+			    unsigned short vid);\
+static int batadv_interface_kill_vid(struct net_device *dev,\
+				     unsigned short vid)\
+{\
+	return __batadv_interface_kill_vid(dev, htons(ETH_P_8021Q), vid);\
+} \
+static int __batadv_interface_kill_vid(struct net_device *dev, __be16 proto,\
+				       unsigned short vid)
+
 #endif /* vlan_insert_tag */
 
 #endif /* < KERNEL_VERSION(3, 10, 0) */
diff --git a/hard-interface.c b/hard-interface.c
index d564af2..c5f871f 100644
--- a/hard-interface.c
+++ b/hard-interface.c
@@ -643,6 +643,8 @@ static int batadv_hard_if_event(struct notifier_block *this,
 
 	if (batadv_softif_is_valid(net_dev) && event == NETDEV_REGISTER) {
 		batadv_sysfs_add_meshif(net_dev);
+		bat_priv = netdev_priv(net_dev);
+		batadv_softif_create_vlan(bat_priv, BATADV_NO_FLAGS);
 		return NOTIFY_DONE;
 	}
 
diff --git a/main.c b/main.c
index f2f1137..fd7fac0 100644
--- a/main.c
+++ b/main.c
@@ -109,6 +109,7 @@ int batadv_mesh_init(struct net_device *soft_iface)
 	spin_lock_init(&bat_priv->gw.list_lock);
 	spin_lock_init(&bat_priv->tvlv.container_list_lock);
 	spin_lock_init(&bat_priv->tvlv.handler_list_lock);
+	spin_lock_init(&bat_priv->softif_vlan_list_lock);
 
 	INIT_HLIST_HEAD(&bat_priv->forw_bat_list);
 	INIT_HLIST_HEAD(&bat_priv->forw_bcast_list);
@@ -118,6 +119,7 @@ int batadv_mesh_init(struct net_device *soft_iface)
 	INIT_LIST_HEAD(&bat_priv->tt.roam_list);
 	INIT_HLIST_HEAD(&bat_priv->tvlv.container_list);
 	INIT_HLIST_HEAD(&bat_priv->tvlv.handler_list);
+	INIT_LIST_HEAD(&bat_priv->softif_vlan_list);
 
 	ret = batadv_originator_init(bat_priv);
 	if (ret < 0)
@@ -127,9 +129,6 @@ int batadv_mesh_init(struct net_device *soft_iface)
 	if (ret < 0)
 		goto err;
 
-	batadv_tt_local_add(soft_iface, soft_iface->dev_addr,
-			    BATADV_NULL_IFINDEX, BATADV_NO_FLAGS);
-
 	ret = batadv_bla_init(bat_priv);
 	if (ret < 0)
 		goto err;
diff --git a/soft-interface.c b/soft-interface.c
index d897194..f7552c5 100644
--- a/soft-interface.c
+++ b/soft-interface.c
@@ -384,6 +384,148 @@ out:
 	return;
 }
 
+/**
+ * batadv_softif_vlan_free_ref - decrease the vlan object refcounter and
+ *  possibly free it
+ * @softif_vlan: the vlan object to release
+ */
+static void batadv_softif_vlan_free_ref(struct batadv_softif_vlan *softif_vlan)
+{
+	if (atomic_dec_and_test(&softif_vlan->refcount))
+		kfree_rcu(softif_vlan, rcu);
+}
+
+/**
+ * batadv_softif_vlan_get - get the vlan object for a specific vid
+ * @bat_priv: the bat priv with all the soft interface information
+ * @vid: the identifier of the vlan object to retrieve
+ *
+ * Return the private data of the vlan matching the vid passed as argument or
+ * NULL otherwise. The refcounter of the returned object is incremented by 1.
+ */
+static struct batadv_softif_vlan *
+batadv_softif_vlan_get(struct batadv_priv *bat_priv, unsigned short vid)
+{
+	struct batadv_softif_vlan *vlan, *vlan_tmp = NULL;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(vlan, &bat_priv->softif_vlan_list, list) {
+		if (vlan->vid != vid)
+			continue;
+
+		if (!atomic_inc_not_zero(&vlan->refcount))
+			continue;
+
+		vlan_tmp = vlan;
+		break;
+	}
+	rcu_read_unlock();
+
+	return vlan_tmp;
+}
+
+/**
+ * batadv_create_vlan - allocate the needed resources for a new vlan
+ * @bat_priv: the bat priv with all the soft interface information
+ * @vid: the VLAN identifier
+ *
+ * Return 0 on success, a negative error otherwise.
+ */
+int batadv_softif_create_vlan(struct batadv_priv *bat_priv, unsigned short vid)
+{
+	struct batadv_softif_vlan *vlan;
+
+	vlan = kzalloc(sizeof(*vlan), GFP_ATOMIC);
+	if (!vlan)
+		return -ENOMEM;
+
+	vlan->vid = vid;
+	atomic_set(&vlan->refcount, 1);
+
+	/* add a new TT local entry. This one will be marked with the NOPURGE
+	 * flag
+	 */
+	batadv_tt_local_add(bat_priv->soft_iface,
+			    bat_priv->soft_iface->dev_addr, vid,
+			    BATADV_NULL_IFINDEX);
+
+	spin_lock_bh(&bat_priv->softif_vlan_list_lock);
+	list_add_rcu(&vlan->list, &bat_priv->softif_vlan_list);
+	spin_unlock_bh(&bat_priv->softif_vlan_list_lock);
+
+	return 0;
+}
+
+/**
+ * batadv_interface_add_vid - ndo_add_vid API implementation
+ * @dev: the netdev of the mesh interface
+ * @vid: identifier of the new vlan
+ *
+ * Set up all the internal structures for handling the new vlan on top of the
+ * mesh interface
+ *
+ * Return 0 on success or a negative error code in case of failure
+ */
+static int batadv_interface_add_vid(struct net_device *dev, __be16 proto,
+				    unsigned short vid)
+{
+	struct batadv_priv *bat_priv = netdev_priv(dev);
+
+	/* only 802.1Q vlans are supported.
+	 * batman-adv does not know how to handle other types
+	 */
+	if (proto != htons(ETH_P_8021Q))
+		return -EINVAL;
+
+	vid |= BATADV_VLAN_HAS_TAG;
+
+	return batadv_softif_create_vlan(bat_priv, vid);
+}
+
+/**
+ * batadv_interface_kill_vid - ndo_kill_vid API implementation
+ * @dev: the netdev of the mesh interface
+ * @vid: identifier of the deleted vlan
+ *
+ * Destroy all the internal structures used to handle the vlan identified by vid
+ * on top of the mesh interface
+ *
+ * Return 0 or -EINVAL if the specified prototype is not ETH_P_8021Q
+ */
+static int batadv_interface_kill_vid(struct net_device *dev, __be16 proto,
+				     unsigned short vid)
+{
+	struct batadv_priv *bat_priv = netdev_priv(dev);
+	struct batadv_softif_vlan *vlan;
+
+	/* only 802.1Q vlans are supported. batman-adv does not know how to
+	 * handle other types
+	 */
+	if (proto != htons(ETH_P_8021Q))
+		return -EINVAL;
+
+	vlan = batadv_softif_vlan_get(bat_priv, vid | BATADV_VLAN_HAS_TAG);
+	if (!vlan)
+		return -ENOENT;
+
+	spin_lock_bh(&bat_priv->softif_vlan_list_lock);
+	list_del_rcu(&vlan->list);
+	spin_unlock_bh(&bat_priv->softif_vlan_list_lock);
+
+	/* explicitly remove the associated TT local entry because it is marked
+	 * with the NOPURGE flag
+	 */
+	batadv_tt_local_remove(bat_priv, dev->dev_addr, vid,
+			       "vlan interface destroyed", false);
+
+	/* batadv_softif_vlan_get() increased the refcounter by 1 */
+	batadv_softif_vlan_free_ref(vlan);
+	/* finally free the vlan object */
+	batadv_softif_vlan_free_ref(vlan);
+
+	return 0;
+}
+
 /* batman-adv network devices have devices nesting below it and are a special
  * "super class" of normal network devices; split their locks off into a
  * separate class since they always nest.
@@ -585,6 +727,8 @@ static const struct net_device_ops batadv_netdev_ops = {
 	.ndo_open = batadv_interface_open,
 	.ndo_stop = batadv_interface_release,
 	.ndo_get_stats = batadv_interface_stats,
+	.ndo_vlan_rx_add_vid = batadv_interface_add_vid,
+	.ndo_vlan_rx_kill_vid = batadv_interface_kill_vid,
 	.ndo_set_mac_address = batadv_interface_set_mac_addr,
 	.ndo_change_mtu = batadv_interface_change_mtu,
 	.ndo_set_rx_mode = batadv_interface_set_rx_mode,
@@ -624,6 +768,7 @@ static void batadv_softif_init_early(struct net_device *dev)
 
 	dev->netdev_ops = &batadv_netdev_ops;
 	dev->destructor = batadv_softif_free;
+	dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
 	dev->tx_queue_len = 0;
 
 	/* can't call min_mtu, because the needed variables
diff --git a/soft-interface.h b/soft-interface.h
index 2f2472c..16d9be6 100644
--- a/soft-interface.h
+++ b/soft-interface.h
@@ -28,5 +28,6 @@ struct net_device *batadv_softif_create(const char *name);
 void batadv_softif_destroy_sysfs(struct net_device *soft_iface);
 int batadv_softif_is_valid(const struct net_device *net_dev);
 extern struct rtnl_link_ops batadv_link_ops;
+int batadv_softif_create_vlan(struct batadv_priv *bat_priv, unsigned short vid);
 
 #endif /* _NET_BATMAN_ADV_SOFT_INTERFACE_H_ */
diff --git a/types.h b/types.h
index 20a1bef..9fdf2c2 100644
--- a/types.h
+++ b/types.h
@@ -530,6 +530,22 @@ struct batadv_priv_nc {
 	struct batadv_hashtable *decoding_hash;
 };
 
+/*
+ * struct batadv_softif_vlan - per VLAN attributes set
+ * @vid: VLAN identifier
+ * @kobj: kobject for sysfs vlan subdirectory
+ * @list: list node for bat_priv::softif_vlan_list
+ * @refcount: number of context where this object is currently in use
+ * @rcu: struct used for freeing in a RCU-safe manner
+ */
+struct batadv_softif_vlan {
+	unsigned short vid;
+	struct kobject *kobj;
+	struct list_head list;
+	atomic_t refcount;
+	struct rcu_head rcu;
+};
+
 /**
  * struct batadv_priv - per mesh interface data
  * @mesh_state: current status of the mesh (inactive/active/deactivating)
@@ -566,6 +582,9 @@ struct batadv_priv_nc {
  * @primary_if: one of the hard interfaces assigned to this mesh interface
  *  becomes the primary interface
  * @bat_algo_ops: routing algorithm used by this mesh interface
+ * @softif_vlan_list: a list of softif_vlan structs, one per VLAN created on top
+ *  of the mesh interface represented by this object
+ * @softif_vlan_list_lock: lock protecting softif_vlan_list
  * @bla: bridge loope avoidance data
  * @debug_log: holding debug logging relevant data
  * @gw: gateway data
@@ -613,6 +632,8 @@ struct batadv_priv {
 	struct work_struct cleanup_work;
 	struct batadv_hard_iface __rcu *primary_if;  /* rcu protected pointer */
 	struct batadv_algo_ops *bat_algo_ops;
+	struct list_head softif_vlan_list;
+	spinlock_t softif_vlan_list_lock; /* protects softif_vlan_list */
 #ifdef CONFIG_BATMAN_ADV_BLA
 	struct batadv_priv_bla bla;
 #endif
-- 
1.8.1.5