[B.A.T.M.A.N.] [PATCH 0/8] pull request for net-next: batman-adv 2016-11-19

[B.A.T.M.A.N.] [PATCH 0/8] pull request for net-next: batman-adv 2016-11-19

[Simon Wunderlich]

Hi David,

this should be our last feature pull request for batman-adv in this round.

Please pull or let me know of any problem!

Thank you,
      Simon

The following changes since commit 93bbaab455f30fd43911e0881a02107a17150a62:

  batman-adv: Reject unicast packet with zero/mcast dst address (2016-11-08 19:02:36 +0100)

are available in the git repository at:

  git://git.open-mesh.org/linux-merge.git tags/batadv-next-for-davem-20161119

for you to fetch changes up to 9b4aec647a92a2464337db10507348aecf0f0fd7:

  batman-adv: fix rare race conditions on interface removal (2016-11-08 19:02:39 +0100)

----------------------------------------------------------------
This feature patchset includes the following changes:

 - 6 patches adding functionality to detect a WiFi interface under
   other virtual interfaces, like VLANs. They introduce a cache for
   the detected the WiFi configuration to avoid RTNL locking in
   critical sections. Patches have been prepared by Marek Lindner
   and Sven Eckelmann

 - Enable automatic module loading for genl requests, by Sven Eckelmann

 - Fix a potential race condition on interface removal. This is not
   happening very often in practice, but requires bigger changes to fix,
   so we are sending this to net-next. By Linus Luessing

----------------------------------------------------------------
Linus Lüssing (1):
      batman-adv: fix rare race conditions on interface removal

Marek Lindner (3):
      batman-adv: refactor wifi interface detection
      batman-adv: additional checks for virtual interfaces on top of WiFi
      batman-adv: retrieve B.A.T.M.A.N. V WiFi neighbor stats from real interface

Sven Eckelmann (4):
      batman-adv: Return non-const ptr in batadv_getlink_net
      batman-adv: Cache the type of wifi device for each hardif
      batman-adv: Update wifi flags on upper link change
      batman-adv: Add module alias for batadv netlink family

 net/batman-adv/bat_iv_ogm.c        |  21 +--
 net/batman-adv/bat_v_elp.c         |  41 +++---
 net/batman-adv/hard-interface.c    | 173 +++++++++++++++++++++--
 net/batman-adv/hard-interface.h    |   5 +-
 net/batman-adv/main.c              |   3 +
 net/batman-adv/send.c              | 283 ++++++++++++++++++++++++++++---------
 net/batman-adv/send.h              |   5 +
 net/batman-adv/translation-table.c |  10 +-
 net/batman-adv/types.h             |  19 +++
 9 files changed, 445 insertions(+), 115 deletions(-)

[B.A.T.M.A.N.] [PATCH 1/8] batman-adv: Return non-const ptr in batadv_getlink_net

[Simon Wunderlich]

From: Sven Eckelmann <sven.eckelmann@open-mesh.com>

The returned net_namespace of batadv_getlink_net may be used with functions
that potentially modify the struct. Thus it must return the pointer as
non-const like rtnl_link_ops::get_link_net does.

Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
---
 net/batman-adv/hard-interface.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c
index a7a462e..fdbb47e 100644
--- a/net/batman-adv/hard-interface.c
+++ b/net/batman-adv/hard-interface.c
@@ -92,8 +92,8 @@ batadv_hardif_get_by_netdev(const struct net_device *net_dev)
  *
  * Return: result of rtnl_link_ops->get_link_net or @fallback_net
  */
-static const struct net *batadv_getlink_net(const struct net_device *netdev,
-					    const struct net *fallback_net)
+static struct net *batadv_getlink_net(const struct net_device *netdev,
+				      struct net *fallback_net)
 {
 	if (!netdev->rtnl_link_ops)
 		return fallback_net;
@@ -116,9 +116,9 @@ static const struct net *batadv_getlink_net(const struct net_device *netdev,
  * Return: true if the devices are each others parent, otherwise false
  */
 static bool batadv_mutual_parents(const struct net_device *dev1,
-				  const struct net *net1,
+				  struct net *net1,
 				  const struct net_device *dev2,
-				  const struct net *net2)
+				  struct net *net2)
 {
 	int dev1_parent_iflink = dev_get_iflink(dev1);
 	int dev2_parent_iflink = dev_get_iflink(dev2);
@@ -154,7 +154,7 @@ static bool batadv_is_on_batman_iface(const struct net_device *net_dev)
 {
 	struct net *net = dev_net(net_dev);
 	struct net_device *parent_dev;
-	const struct net *parent_net;
+	struct net *parent_net;
 	bool ret;
 
 	/* check if this is a batman-adv mesh interface */
-- 
2.10.2

[B.A.T.M.A.N.] [PATCH 2/8] batman-adv: refactor wifi interface detection

[Simon Wunderlich]

From: Marek Lindner <mareklindner@neomailbox.ch>

The ELP protocol requires cfg80211 to auto-detect the WiFi througput
to a given neighbor. Use batadv_is_cfg80211_netdev() to determine
whether or not an interface is eligible.

Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
---
 net/batman-adv/bat_v_elp.c      | 29 ++++++++++++++---------------
 net/batman-adv/hard-interface.c | 26 +++++++++++++++++++++-----
 net/batman-adv/hard-interface.h |  1 +
 3 files changed, 36 insertions(+), 20 deletions(-)

diff --git a/net/batman-adv/bat_v_elp.c b/net/batman-adv/bat_v_elp.c
index 54bdd41..e601def 100644
--- a/net/batman-adv/bat_v_elp.c
+++ b/net/batman-adv/bat_v_elp.c
@@ -90,22 +90,21 @@ static u32 batadv_v_elp_get_throughput(struct batadv_hardif_neigh_node *neigh)
 	 * cfg80211 API
 	 */
 	if (batadv_is_wifi_netdev(hard_iface->net_dev)) {
-		if (hard_iface->net_dev->ieee80211_ptr) {
-			ret = cfg80211_get_station(hard_iface->net_dev,
-						   neigh->addr, &sinfo);
-			if (ret == -ENOENT) {
-				/* Node is not associated anymore! It would be
-				 * possible to delete this neighbor. For now set
-				 * the throughput metric to 0.
-				 */
-				return 0;
-			}
-			if (!ret)
-				return sinfo.expected_throughput / 100;
+		if (!batadv_is_cfg80211_netdev(hard_iface->net_dev))
+			/* unsupported WiFi driver version */
+			goto default_throughput;
+
+		ret = cfg80211_get_station(hard_iface->net_dev,
+					   neigh->addr, &sinfo);
+		if (ret == -ENOENT) {
+			/* Node is not associated anymore! It would be
+			 * possible to delete this neighbor. For now set
+			 * the throughput metric to 0.
+			 */
+			return 0;
 		}
-
-		/* unsupported WiFi driver version */
-		goto default_throughput;
+		if (!ret)
+			return sinfo.expected_throughput / 100;
 	}
 
 	/* if not a wifi interface, check if this device provides data via
diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c
index fdbb47e..c3fbc1b 100644
--- a/net/batman-adv/hard-interface.c
+++ b/net/batman-adv/hard-interface.c
@@ -202,6 +202,26 @@ static bool batadv_is_valid_iface(const struct net_device *net_dev)
 }
 
 /**
+ * batadv_is_cfg80211_netdev - check if the given net_device struct is a
+ *  cfg80211 wifi interface
+ * @net_device: the device to check
+ *
+ * Return: true if the net device is a cfg80211 wireless device, false
+ *  otherwise.
+ */
+bool batadv_is_cfg80211_netdev(struct net_device *net_device)
+{
+	if (!net_device)
+		return false;
+
+	/* cfg80211 drivers have to set ieee80211_ptr */
+	if (net_device->ieee80211_ptr)
+		return true;
+
+	return false;
+}
+
+/**
  * batadv_is_wifi_netdev - check if the given net_device struct is a wifi
  *  interface
  * @net_device: the device to check
@@ -221,11 +241,7 @@ bool batadv_is_wifi_netdev(struct net_device *net_device)
 		return true;
 #endif
 
-	/* cfg80211 drivers have to set ieee80211_ptr */
-	if (net_device->ieee80211_ptr)
-		return true;
-
-	return false;
+	return batadv_is_cfg80211_netdev(net_device);
 }
 
 /**
diff --git a/net/batman-adv/hard-interface.h b/net/batman-adv/hard-interface.h
index a043182..7f9acab 100644
--- a/net/batman-adv/hard-interface.h
+++ b/net/batman-adv/hard-interface.h
@@ -65,6 +65,7 @@ enum batadv_hard_if_cleanup {
 
 extern struct notifier_block batadv_hard_if_notifier;
 
+bool batadv_is_cfg80211_netdev(struct net_device *net_device);
 bool batadv_is_wifi_netdev(struct net_device *net_device);
 bool batadv_is_wifi_iface(int ifindex);
 struct batadv_hard_iface*
-- 
2.10.2

[B.A.T.M.A.N.] [PATCH 3/8] batman-adv: Cache the type of wifi device for each hardif

[Simon Wunderlich]

From: Sven Eckelmann <sven.eckelmann@open-mesh.com>

batman-adv is requiring the type of wifi device in different contexts. Some
of them can take the rtnl semaphore and some of them already have the
semaphore taken. But even others don't allow that the semaphore will be
taken.

The data has to be retrieved when the hardif is added to batman-adv because
some of the wifi information for an hardif will only be available with rtnl
lock. It can then be cached in the batadv_hard_iface and the functions
is_wifi_netdev and is_cfg80211_netdev can just compare the correct bits
without imposing extra locking requirements.

Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
---
 net/batman-adv/bat_iv_ogm.c        |  2 +-
 net/batman-adv/bat_v_elp.c         |  8 ++--
 net/batman-adv/hard-interface.c    | 82 +++++++++++++++++++++++++++++++-------
 net/batman-adv/hard-interface.h    |  5 +--
 net/batman-adv/translation-table.c | 10 ++++-
 net/batman-adv/types.h             | 13 ++++++
 6 files changed, 95 insertions(+), 25 deletions(-)

diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c
index bd39247..36d8818 100644
--- a/net/batman-adv/bat_iv_ogm.c
+++ b/net/batman-adv/bat_iv_ogm.c
@@ -1272,7 +1272,7 @@ static bool batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node,
 	 */
 	tq_iface_penalty = BATADV_TQ_MAX_VALUE;
 	if (if_outgoing && (if_incoming == if_outgoing) &&
-	    batadv_is_wifi_netdev(if_outgoing->net_dev))
+	    batadv_is_wifi_hardif(if_outgoing))
 		tq_iface_penalty = batadv_hop_penalty(BATADV_TQ_MAX_VALUE,
 						      bat_priv);
 
diff --git a/net/batman-adv/bat_v_elp.c b/net/batman-adv/bat_v_elp.c
index e601def..0d78689 100644
--- a/net/batman-adv/bat_v_elp.c
+++ b/net/batman-adv/bat_v_elp.c
@@ -89,8 +89,8 @@ static u32 batadv_v_elp_get_throughput(struct batadv_hardif_neigh_node *neigh)
 	/* if this is a wireless device, then ask its throughput through
 	 * cfg80211 API
 	 */
-	if (batadv_is_wifi_netdev(hard_iface->net_dev)) {
-		if (!batadv_is_cfg80211_netdev(hard_iface->net_dev))
+	if (batadv_is_wifi_hardif(hard_iface)) {
+		if (!batadv_is_cfg80211_hardif(hard_iface))
 			/* unsupported WiFi driver version */
 			goto default_throughput;
 
@@ -186,7 +186,7 @@ batadv_v_elp_wifi_neigh_probe(struct batadv_hardif_neigh_node *neigh)
 	int elp_skb_len;
 
 	/* this probing routine is for Wifi neighbours only */
-	if (!batadv_is_wifi_netdev(hard_iface->net_dev))
+	if (!batadv_is_wifi_hardif(hard_iface))
 		return true;
 
 	/* probe the neighbor only if no unicast packets have been sent
@@ -351,7 +351,7 @@ int batadv_v_elp_iface_enable(struct batadv_hard_iface *hard_iface)
 	/* warn the user (again) if there is no throughput data is available */
 	hard_iface->bat_v.flags &= ~BATADV_WARNING_DEFAULT;
 
-	if (batadv_is_wifi_netdev(hard_iface->net_dev))
+	if (batadv_is_wifi_hardif(hard_iface))
 		hard_iface->bat_v.flags &= ~BATADV_FULL_DUPLEX;
 
 	INIT_DELAYED_WORK(&hard_iface->bat_v.elp_wq,
diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c
index c3fbc1b..57e8912 100644
--- a/net/batman-adv/hard-interface.c
+++ b/net/batman-adv/hard-interface.c
@@ -202,6 +202,30 @@ static bool batadv_is_valid_iface(const struct net_device *net_dev)
 }
 
 /**
+ * batadv_is_wext_netdev - check if the given net_device struct is a
+ *  wext wifi interface
+ * @net_device: the device to check
+ *
+ * Return: true if the net device is a wext wireless device, false
+ *  otherwise.
+ */
+static bool batadv_is_wext_netdev(struct net_device *net_device)
+{
+	if (!net_device)
+		return false;
+
+#ifdef CONFIG_WIRELESS_EXT
+	/* pre-cfg80211 drivers have to implement WEXT, so it is possible to
+	 * check for wireless_handlers != NULL
+	 */
+	if (net_device->wireless_handlers)
+		return true;
+#endif
+
+	return false;
+}
+
+/**
  * batadv_is_cfg80211_netdev - check if the given net_device struct is a
  *  cfg80211 wifi interface
  * @net_device: the device to check
@@ -209,7 +233,7 @@ static bool batadv_is_valid_iface(const struct net_device *net_dev)
  * Return: true if the net device is a cfg80211 wireless device, false
  *  otherwise.
  */
-bool batadv_is_cfg80211_netdev(struct net_device *net_device)
+static bool batadv_is_cfg80211_netdev(struct net_device *net_device)
 {
 	if (!net_device)
 		return false;
@@ -222,26 +246,53 @@ bool batadv_is_cfg80211_netdev(struct net_device *net_device)
 }
 
 /**
- * batadv_is_wifi_netdev - check if the given net_device struct is a wifi
- *  interface
+ * batadv_wifi_flags_evaluate - calculate wifi flags for net_device
  * @net_device: the device to check
  *
+ * Return: batadv_hard_iface_wifi_flags flags of the device
+ */
+static u32 batadv_wifi_flags_evaluate(struct net_device *net_device)
+{
+	u32 wifi_flags = 0;
+
+	if (batadv_is_wext_netdev(net_device))
+		wifi_flags |= BATADV_HARDIF_WIFI_WEXT_DIRECT;
+
+	if (batadv_is_cfg80211_netdev(net_device))
+		wifi_flags |= BATADV_HARDIF_WIFI_CFG80211_DIRECT;
+
+	return wifi_flags;
+}
+
+/**
+ * batadv_is_cfg80211_hardif - check if the given hardif is a cfg80211 wifi
+ *  interface
+ * @hard_iface: the device to check
+ *
+ * Return: true if the net device is a cfg80211 wireless device, false
+ *  otherwise.
+ */
+bool batadv_is_cfg80211_hardif(struct batadv_hard_iface *hard_iface)
+{
+	u32 allowed_flags = 0;
+
+	allowed_flags |= BATADV_HARDIF_WIFI_CFG80211_DIRECT;
+
+	return !!(hard_iface->wifi_flags & allowed_flags);
+}
+
+/**
+ * batadv_is_wifi_hardif - check if the given hardif is a wifi interface
+ * @hard_iface: the device to check
+ *
  * Return: true if the net device is a 802.11 wireless device, false otherwise.
  */
-bool batadv_is_wifi_netdev(struct net_device *net_device)
+bool batadv_is_wifi_hardif(struct batadv_hard_iface *hard_iface)
 {
-	if (!net_device)
+	if (!hard_iface)
 		return false;
 
-#ifdef CONFIG_WIRELESS_EXT
-	/* pre-cfg80211 drivers have to implement WEXT, so it is possible to
-	 * check for wireless_handlers != NULL
-	 */
-	if (net_device->wireless_handlers)
-		return true;
-#endif
-
-	return batadv_is_cfg80211_netdev(net_device);
+	return hard_iface->wifi_flags != 0;
 }
 
 /**
@@ -765,7 +816,8 @@ batadv_hardif_add_interface(struct net_device *net_dev)
 	kref_init(&hard_iface->refcount);
 
 	hard_iface->num_bcasts = BATADV_NUM_BCASTS_DEFAULT;
-	if (batadv_is_wifi_netdev(net_dev))
+	hard_iface->wifi_flags = batadv_wifi_flags_evaluate(net_dev);
+	if (batadv_is_wifi_hardif(hard_iface))
 		hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS;
 
 	batadv_v_hardif_init(hard_iface);
diff --git a/net/batman-adv/hard-interface.h b/net/batman-adv/hard-interface.h
index 7f9acab..7281dd2 100644
--- a/net/batman-adv/hard-interface.h
+++ b/net/batman-adv/hard-interface.h
@@ -65,9 +65,8 @@ enum batadv_hard_if_cleanup {
 
 extern struct notifier_block batadv_hard_if_notifier;
 
-bool batadv_is_cfg80211_netdev(struct net_device *net_device);
-bool batadv_is_wifi_netdev(struct net_device *net_device);
-bool batadv_is_wifi_iface(int ifindex);
+bool batadv_is_cfg80211_hardif(struct batadv_hard_iface *hard_iface);
+bool batadv_is_wifi_hardif(struct batadv_hard_iface *hard_iface);
 struct batadv_hard_iface*
 batadv_hardif_get_by_netdev(const struct net_device *net_dev);
 int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface,
diff --git a/net/batman-adv/translation-table.c b/net/batman-adv/translation-table.c
index 3cae8f4f..447f949 100644
--- a/net/batman-adv/translation-table.c
+++ b/net/batman-adv/translation-table.c
@@ -646,6 +646,7 @@ bool batadv_tt_local_add(struct net_device *soft_iface, const u8 *addr,
 	struct net *net = dev_net(soft_iface);
 	struct batadv_softif_vlan *vlan;
 	struct net_device *in_dev = NULL;
+	struct batadv_hard_iface *in_hardif = NULL;
 	struct hlist_head *head;
 	struct batadv_tt_orig_list_entry *orig_entry;
 	int hash_added, table_size, packet_size_max;
@@ -657,6 +658,9 @@ bool batadv_tt_local_add(struct net_device *soft_iface, const u8 *addr,
 	if (ifindex != BATADV_NULL_IFINDEX)
 		in_dev = dev_get_by_index(net, ifindex);
 
+	if (in_dev)
+		in_hardif = batadv_hardif_get_by_netdev(in_dev);
+
 	tt_local = batadv_tt_local_hash_find(bat_priv, addr, vid);
 
 	if (!is_multicast_ether_addr(addr))
@@ -730,7 +734,7 @@ bool batadv_tt_local_add(struct net_device *soft_iface, const u8 *addr,
 	 */
 	tt_local->common.flags = BATADV_TT_CLIENT_NEW;
 	tt_local->common.vid = vid;
-	if (batadv_is_wifi_netdev(in_dev))
+	if (batadv_is_wifi_hardif(in_hardif))
 		tt_local->common.flags |= BATADV_TT_CLIENT_WIFI;
 	kref_init(&tt_local->common.refcount);
 	tt_local->last_seen = jiffies;
@@ -790,7 +794,7 @@ bool batadv_tt_local_add(struct net_device *soft_iface, const u8 *addr,
 	 */
 	remote_flags = tt_local->common.flags & BATADV_TT_REMOTE_MASK;
 
-	if (batadv_is_wifi_netdev(in_dev))
+	if (batadv_is_wifi_hardif(in_hardif))
 		tt_local->common.flags |= BATADV_TT_CLIENT_WIFI;
 	else
 		tt_local->common.flags &= ~BATADV_TT_CLIENT_WIFI;
@@ -814,6 +818,8 @@ bool batadv_tt_local_add(struct net_device *soft_iface, const u8 *addr,
 
 	ret = true;
 out:
+	if (in_hardif)
+		batadv_hardif_put(in_hardif);
 	if (in_dev)
 		dev_put(in_dev);
 	if (tt_local)
diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h
index 98ebac0..1bcce32 100644
--- a/net/batman-adv/types.h
+++ b/net/batman-adv/types.h
@@ -119,11 +119,23 @@ struct batadv_hard_iface_bat_v {
 };
 
 /**
+ * enum batadv_hard_iface_wifi_flags - Flags describing the wifi configuration
+ *  of a batadv_hard_iface
+ * @BATADV_HARDIF_WIFI_WEXT_DIRECT: it is a wext wifi device
+ * @BATADV_HARDIF_WIFI_CFG80211_DIRECT: it is a cfg80211 wifi device
+ */
+enum batadv_hard_iface_wifi_flags {
+	BATADV_HARDIF_WIFI_WEXT_DIRECT = BIT(0),
+	BATADV_HARDIF_WIFI_CFG80211_DIRECT = BIT(1),
+};
+
+/**
  * struct batadv_hard_iface - network device known to batman-adv
  * @list: list node for batadv_hardif_list
  * @if_num: identificator of the interface
  * @if_status: status of the interface for batman-adv
  * @num_bcasts: number of payload re-broadcasts on this interface (ARQ)
+ * @wifi_flags: flags whether this is (directly or indirectly) a wifi interface
  * @net_dev: pointer to the net_device
  * @hardif_obj: kobject of the per interface sysfs "mesh" directory
  * @refcount: number of contexts the object is used
@@ -142,6 +154,7 @@ struct batadv_hard_iface {
 	s16 if_num;
 	char if_status;
 	u8 num_bcasts;
+	u32 wifi_flags;
 	struct net_device *net_dev;
 	struct kobject *hardif_obj;
 	struct kref refcount;
-- 
2.10.2

[B.A.T.M.A.N.] [PATCH 4/8] batman-adv: additional checks for virtual interfaces on top of WiFi

[Simon Wunderlich]

From: Marek Lindner <mareklindner@neomailbox.ch>

In a few situations batman-adv tries to determine whether a given interface
is a WiFi interface to enable specific WiFi optimizations. If the interface
batman-adv has been configured with is a virtual interface (e.g. VLAN) it
would not be properly detected as WiFi interface and thus not benefit from
the special WiFi treatment.
This patch changes that by peeking under the hood whenever a virtual
interface is in play.

Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
[sven.eckelmann@open-mesh.com: integrate in wifi_flags caching, retrieve
 namespace of link interface]
Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
---
 net/batman-adv/hard-interface.c | 58 +++++++++++++++++++++++++++++++++++++++++
 net/batman-adv/types.h          |  4 +++
 2 files changed, 62 insertions(+)

diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c
index 57e8912..df31f2f 100644
--- a/net/batman-adv/hard-interface.c
+++ b/net/batman-adv/hard-interface.c
@@ -202,6 +202,47 @@ static bool batadv_is_valid_iface(const struct net_device *net_dev)
 }
 
 /**
+ * batadv_get_real_netdevice - check if the given netdev struct is a virtual
+ *  interface on top of another 'real' interface
+ * @netdev: the device to check
+ *
+ * Return: the 'real' net device or the original net device and NULL in case
+ *  of an error.
+ */
+static struct net_device *batadv_get_real_netdevice(struct net_device *netdev)
+{
+	struct batadv_hard_iface *hard_iface = NULL;
+	struct net_device *real_netdev = NULL;
+	struct net *real_net;
+	struct net *net;
+	int ifindex;
+
+	ASSERT_RTNL();
+
+	if (!netdev)
+		return NULL;
+
+	if (netdev->ifindex == dev_get_iflink(netdev)) {
+		dev_hold(netdev);
+		return netdev;
+	}
+
+	hard_iface = batadv_hardif_get_by_netdev(netdev);
+	if (!hard_iface || !hard_iface->soft_iface)
+		goto out;
+
+	net = dev_net(hard_iface->soft_iface);
+	ifindex = dev_get_iflink(netdev);
+	real_net = batadv_getlink_net(netdev, net);
+	real_netdev = dev_get_by_index(real_net, ifindex);
+
+out:
+	if (hard_iface)
+		batadv_hardif_put(hard_iface);
+	return real_netdev;
+}
+
+/**
  * batadv_is_wext_netdev - check if the given net_device struct is a
  *  wext wifi interface
  * @net_device: the device to check
@@ -254,6 +295,7 @@ static bool batadv_is_cfg80211_netdev(struct net_device *net_device)
 static u32 batadv_wifi_flags_evaluate(struct net_device *net_device)
 {
 	u32 wifi_flags = 0;
+	struct net_device *real_netdev;
 
 	if (batadv_is_wext_netdev(net_device))
 		wifi_flags |= BATADV_HARDIF_WIFI_WEXT_DIRECT;
@@ -261,6 +303,21 @@ static u32 batadv_wifi_flags_evaluate(struct net_device *net_device)
 	if (batadv_is_cfg80211_netdev(net_device))
 		wifi_flags |= BATADV_HARDIF_WIFI_CFG80211_DIRECT;
 
+	real_netdev = batadv_get_real_netdevice(net_device);
+	if (!real_netdev)
+		return wifi_flags;
+
+	if (real_netdev == net_device)
+		goto out;
+
+	if (batadv_is_wext_netdev(real_netdev))
+		wifi_flags |= BATADV_HARDIF_WIFI_WEXT_INDIRECT;
+
+	if (batadv_is_cfg80211_netdev(real_netdev))
+		wifi_flags |= BATADV_HARDIF_WIFI_CFG80211_INDIRECT;
+
+out:
+	dev_put(real_netdev);
 	return wifi_flags;
 }
 
@@ -277,6 +334,7 @@ bool batadv_is_cfg80211_hardif(struct batadv_hard_iface *hard_iface)
 	u32 allowed_flags = 0;
 
 	allowed_flags |= BATADV_HARDIF_WIFI_CFG80211_DIRECT;
+	allowed_flags |= BATADV_HARDIF_WIFI_CFG80211_INDIRECT;
 
 	return !!(hard_iface->wifi_flags & allowed_flags);
 }
diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h
index 1bcce32..caa00a5 100644
--- a/net/batman-adv/types.h
+++ b/net/batman-adv/types.h
@@ -123,10 +123,14 @@ struct batadv_hard_iface_bat_v {
  *  of a batadv_hard_iface
  * @BATADV_HARDIF_WIFI_WEXT_DIRECT: it is a wext wifi device
  * @BATADV_HARDIF_WIFI_CFG80211_DIRECT: it is a cfg80211 wifi device
+ * @BATADV_HARDIF_WIFI_WEXT_INDIRECT: link device is a wext wifi device
+ * @BATADV_HARDIF_WIFI_CFG80211_INDIRECT: link device is a cfg80211 wifi device
  */
 enum batadv_hard_iface_wifi_flags {
 	BATADV_HARDIF_WIFI_WEXT_DIRECT = BIT(0),
 	BATADV_HARDIF_WIFI_CFG80211_DIRECT = BIT(1),
+	BATADV_HARDIF_WIFI_WEXT_INDIRECT = BIT(2),
+	BATADV_HARDIF_WIFI_CFG80211_INDIRECT = BIT(3),
 };
 
 /**
-- 
2.10.2

[B.A.T.M.A.N.] [PATCH 5/8] batman-adv: retrieve B.A.T.M.A.N. V WiFi neighbor stats from real interface

[Simon Wunderlich]

From: Marek Lindner <mareklindner@neomailbox.ch>

Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
[sven.eckelmann@open-mesh.com: re-add batadv_get_real_netdev to take rtnl
 semaphore for batadv_get_real_netdevice]
Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
---
 net/batman-adv/bat_v_elp.c      | 10 ++++++++--
 net/batman-adv/hard-interface.c | 22 ++++++++++++++++++++++
 net/batman-adv/hard-interface.h |  1 +
 3 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/net/batman-adv/bat_v_elp.c b/net/batman-adv/bat_v_elp.c
index 0d78689..f2fb2f0 100644
--- a/net/batman-adv/bat_v_elp.c
+++ b/net/batman-adv/bat_v_elp.c
@@ -75,6 +75,7 @@ static u32 batadv_v_elp_get_throughput(struct batadv_hardif_neigh_node *neigh)
 {
 	struct batadv_hard_iface *hard_iface = neigh->if_incoming;
 	struct ethtool_link_ksettings link_settings;
+	struct net_device *real_netdev;
 	struct station_info sinfo;
 	u32 throughput;
 	int ret;
@@ -94,8 +95,13 @@ static u32 batadv_v_elp_get_throughput(struct batadv_hardif_neigh_node *neigh)
 			/* unsupported WiFi driver version */
 			goto default_throughput;
 
-		ret = cfg80211_get_station(hard_iface->net_dev,
-					   neigh->addr, &sinfo);
+		real_netdev = batadv_get_real_netdev(hard_iface->net_dev);
+		if (!real_netdev)
+			goto default_throughput;
+
+		ret = cfg80211_get_station(real_netdev, neigh->addr, &sinfo);
+
+		dev_put(real_netdev);
 		if (ret == -ENOENT) {
 			/* Node is not associated anymore! It would be
 			 * possible to delete this neighbor. For now set
diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c
index df31f2f..ca743a5 100644
--- a/net/batman-adv/hard-interface.c
+++ b/net/batman-adv/hard-interface.c
@@ -206,6 +206,9 @@ static bool batadv_is_valid_iface(const struct net_device *net_dev)
  *  interface on top of another 'real' interface
  * @netdev: the device to check
  *
+ * Callers must hold the rtnl semaphore. You may want batadv_get_real_netdev()
+ * instead of this.
+ *
  * Return: the 'real' net device or the original net device and NULL in case
  *  of an error.
  */
@@ -243,6 +246,25 @@ static struct net_device *batadv_get_real_netdevice(struct net_device *netdev)
 }
 
 /**
+ * batadv_get_real_netdev - check if the given net_device struct is a virtual
+ *  interface on top of another 'real' interface
+ * @net_device: the device to check
+ *
+ * Return: the 'real' net device or the original net device and NULL in case
+ *  of an error.
+ */
+struct net_device *batadv_get_real_netdev(struct net_device *net_device)
+{
+	struct net_device *real_netdev;
+
+	rtnl_lock();
+	real_netdev = batadv_get_real_netdevice(net_device);
+	rtnl_unlock();
+
+	return real_netdev;
+}
+
+/**
  * batadv_is_wext_netdev - check if the given net_device struct is a
  *  wext wifi interface
  * @net_device: the device to check
diff --git a/net/batman-adv/hard-interface.h b/net/batman-adv/hard-interface.h
index 7281dd2..d6309a4 100644
--- a/net/batman-adv/hard-interface.h
+++ b/net/batman-adv/hard-interface.h
@@ -65,6 +65,7 @@ enum batadv_hard_if_cleanup {
 
 extern struct notifier_block batadv_hard_if_notifier;
 
+struct net_device *batadv_get_real_netdev(struct net_device *net_device);
 bool batadv_is_cfg80211_hardif(struct batadv_hard_iface *hard_iface);
 bool batadv_is_wifi_hardif(struct batadv_hard_iface *hard_iface);
 struct batadv_hard_iface*
-- 
2.10.2

[B.A.T.M.A.N.] [PATCH 6/8] batman-adv: Update wifi flags on upper link change

[Simon Wunderlich]

From: Sven Eckelmann <sven.eckelmann@open-mesh.com>

Things like VLANs don't have their link set when they are created. Thus
the wifi flags have to be evaluated later to fix their contents for the
link interface.

Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
---
 net/batman-adv/hard-interface.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c
index ca743a5..61a431a 100644
--- a/net/batman-adv/hard-interface.c
+++ b/net/batman-adv/hard-interface.c
@@ -1006,6 +1006,11 @@ static int batadv_hard_if_event(struct notifier_block *this,
 		if (hard_iface == primary_if)
 			batadv_primary_if_update_addr(bat_priv, NULL);
 		break;
+	case NETDEV_CHANGEUPPER:
+		hard_iface->wifi_flags = batadv_wifi_flags_evaluate(net_dev);
+		if (batadv_is_wifi_hardif(hard_iface))
+			hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS;
+		break;
 	default:
 		break;
 	}
-- 
2.10.2

[B.A.T.M.A.N.] [PATCH 7/8] batman-adv: Add module alias for batadv netlink family

[Simon Wunderlich]

From: Sven Eckelmann <sven@narfation.org>

The batman-adv module has to be loaded to fulfill genl request by the
userspace. When it is not loaded then requests will fail. It is therefore
useful to get the module automatically loaded when such a request is made.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
---
 net/batman-adv/main.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/batman-adv/main.c b/net/batman-adv/main.c
index 6b5dae6..d46415e 100644
--- a/net/batman-adv/main.c
+++ b/net/batman-adv/main.c
@@ -23,6 +23,7 @@
 #include <linux/crc32c.h>
 #include <linux/errno.h>
 #include <linux/fs.h>
+#include <linux/genetlink.h>
 #include <linux/if_ether.h>
 #include <linux/if_vlan.h>
 #include <linux/init.h>
@@ -44,6 +45,7 @@
 #include <linux/workqueue.h>
 #include <net/dsfield.h>
 #include <net/rtnetlink.h>
+#include <uapi/linux/batman_adv.h>
 
 #include "bat_algo.h"
 #include "bat_iv_ogm.h"
@@ -648,3 +650,4 @@ MODULE_DESCRIPTION(BATADV_DRIVER_DESC);
 MODULE_SUPPORTED_DEVICE(BATADV_DRIVER_DEVICE);
 MODULE_VERSION(BATADV_SOURCE_VERSION);
 MODULE_ALIAS_RTNL_LINK("batadv");
+MODULE_ALIAS_GENL_FAMILY(BATADV_NL_NAME);
-- 
2.10.2

[B.A.T.M.A.N.] [PATCH 8/8] batman-adv: fix rare race conditions on interface removal

[Simon Wunderlich]

From: Linus Lüssing <linus.luessing@c0d3.blue>

In rare cases during shutdown the following general protection fault can
happen:

  general protection fault: 0000 [#1] SMP
  Modules linked in: batman_adv(O-) [...]
  CPU: 3 PID: 1714 Comm: rmmod Tainted: G           O    4.6.0-rc6+ #1
  [...]
  Call Trace:
   [<ffffffffa0363294>] batadv_hardif_disable_interface+0x29a/0x3a6 [batman_adv]
   [<ffffffffa0373db4>] batadv_softif_destroy_netlink+0x4b/0xa4 [batman_adv]
   [<ffffffff813b52f3>] __rtnl_link_unregister+0x48/0x92
   [<ffffffff813b9240>] rtnl_link_unregister+0xc1/0xdb
   [<ffffffff8108547c>] ? bit_waitqueue+0x87/0x87
   [<ffffffffa03850d2>] batadv_exit+0x1a/0xf48 [batman_adv]
   [<ffffffff810c26f9>] SyS_delete_module+0x136/0x1b0
   [<ffffffff8144dc65>] entry_SYSCALL_64_fastpath+0x18/0xa8
   [<ffffffff8108aaca>] ? trace_hardirqs_off_caller+0x37/0xa6
  Code: 89 f7 e8 21 bd 0d e1 4d 85 e4 75 0e 31 f6 48 c7 c7 50 d7 3b a0 e8 50 16 f2 e0 49 8b 9c 24 28 01 00 00 48 85 db 0f 84 b2 00 00 00 <48> 8b 03 4d 85 ed 48 89 45 c8 74 09 4c 39 ab f8 00 00 00 75 1c
  RIP  [<ffffffffa0371852>] batadv_purge_outstanding_packets+0x1c8/0x291 [batman_adv]
   RSP <ffff88001da5fd78>
  ---[ end trace 803b9bdc6a4a952b ]---
  Kernel panic - not syncing: Fatal exception in interrupt
  Kernel Offset: disabled
  ---[ end Kernel panic - not syncing: Fatal exception in interrupt

It does not happen often, but may potentially happen when frequently
shutting down and reinitializing an interface. With some carefully
placed msleep()s/mdelay()s it can be reproduced easily.

The issue is, that on interface removal, any still running worker thread
of a forwarding packet will race with the interface purging routine to
free a forwarding packet. Temporarily giving up a spin-lock to be able
to sleep in the purging routine is not safe.

Furthermore, there is a potential general protection fault not just for
the purging side shown above, but also on the worker side: Temporarily
removing a forw_packet from the according forw_{bcast,bat}_list will make
it impossible for the purging routine to catch and cancel it.

 # How this patch tries to fix it:

With this patch we split the queue purging into three steps: Step 1),
removing forward packets from the queue of an interface and by that
claim it as our responsibility to free.

Step 2), we are either lucky to cancel a pending worker before it starts
to run. Or if it is already running, we wait and let it do its thing,
except two things:

Through the claiming in step 1) we prevent workers from a) re-arming
themselves. And b) prevent workers from freeing packets which we still
hold in the interface purging routine.

Finally, step 3, we are sure that no forwarding packets are pending or
even running anymore on the interface to remove. We can then safely free
the claimed forwarding packets.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
---
 net/batman-adv/bat_iv_ogm.c |  19 +--
 net/batman-adv/send.c       | 283 +++++++++++++++++++++++++++++++++-----------
 net/batman-adv/send.h       |   5 +
 net/batman-adv/types.h      |   2 +
 4 files changed, 227 insertions(+), 82 deletions(-)

diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c
index 36d8818..f00f666 100644
--- a/net/batman-adv/bat_iv_ogm.c
+++ b/net/batman-adv/bat_iv_ogm.c
@@ -717,17 +717,10 @@ static void batadv_iv_ogm_aggregate_new(const unsigned char *packet_buff,
 	if (direct_link)
 		forw_packet_aggr->direct_link_flags |= 1;
 
-	/* add new packet to packet list */
-	spin_lock_bh(&bat_priv->forw_bat_list_lock);
-	hlist_add_head(&forw_packet_aggr->list, &bat_priv->forw_bat_list);
-	spin_unlock_bh(&bat_priv->forw_bat_list_lock);
-
-	/* start timer for this packet */
 	INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work,
 			  batadv_iv_send_outstanding_bat_ogm_packet);
-	queue_delayed_work(batadv_event_workqueue,
-			   &forw_packet_aggr->delayed_work,
-			   send_time - jiffies);
+
+	batadv_forw_packet_ogmv1_queue(bat_priv, forw_packet_aggr, send_time);
 }
 
 /* aggregate a new packet into the existing ogm packet */
@@ -1789,9 +1782,6 @@ static void batadv_iv_send_outstanding_bat_ogm_packet(struct work_struct *work)
 	forw_packet = container_of(delayed_work, struct batadv_forw_packet,
 				   delayed_work);
 	bat_priv = netdev_priv(forw_packet->if_incoming->soft_iface);
-	spin_lock_bh(&bat_priv->forw_bat_list_lock);
-	hlist_del(&forw_packet->list);
-	spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 
 	if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING) {
 		dropped = true;
@@ -1813,7 +1803,10 @@ static void batadv_iv_send_outstanding_bat_ogm_packet(struct work_struct *work)
 		batadv_iv_ogm_schedule(forw_packet->if_incoming);
 
 out:
-	batadv_forw_packet_free(forw_packet, dropped);
+	/* do we get something for free()? */
+	if (batadv_forw_packet_steal(forw_packet,
+				     &bat_priv->forw_bat_list_lock))
+		batadv_forw_packet_free(forw_packet, dropped);
 }
 
 static int batadv_iv_ogm_receive(struct sk_buff *skb,
diff --git a/net/batman-adv/send.c b/net/batman-adv/send.c
index 9ea272e..49021b7 100644
--- a/net/batman-adv/send.c
+++ b/net/batman-adv/send.c
@@ -19,6 +19,7 @@
 #include "main.h"
 
 #include <linux/atomic.h>
+#include <linux/bug.h>
 #include <linux/byteorder/generic.h>
 #include <linux/errno.h>
 #include <linux/etherdevice.h>
@@ -520,6 +521,8 @@ batadv_forw_packet_alloc(struct batadv_hard_iface *if_incoming,
 	if (if_outgoing)
 		kref_get(&if_outgoing->refcount);
 
+	INIT_HLIST_NODE(&forw_packet->list);
+	INIT_HLIST_NODE(&forw_packet->cleanup_list);
 	forw_packet->skb = NULL;
 	forw_packet->queue_left = queue_left;
 	forw_packet->if_incoming = if_incoming;
@@ -535,19 +538,191 @@ batadv_forw_packet_alloc(struct batadv_hard_iface *if_incoming,
 	return NULL;
 }
 
+/**
+ * batadv_forw_packet_was_stolen - check whether someone stole this packet
+ * @forw_packet: the forwarding packet to check
+ *
+ * This function checks whether the given forwarding packet was claimed by
+ * someone else for free().
+ *
+ * Return: True if someone stole it, false otherwise.
+ */
+static bool
+batadv_forw_packet_was_stolen(struct batadv_forw_packet *forw_packet)
+{
+	return !hlist_unhashed(&forw_packet->cleanup_list);
+}
+
+/**
+ * batadv_forw_packet_steal - claim a forw_packet for free()
+ * @forw_packet: the forwarding packet to steal
+ * @lock: a key to the store to steal from (e.g. forw_{bat,bcast}_list_lock)
+ *
+ * This function tries to steal a specific forw_packet from global
+ * visibility for the purpose of getting it for free(). That means
+ * the caller is *not* allowed to requeue it afterwards.
+ *
+ * Return: True if stealing was successful. False if someone else stole it
+ * before us.
+ */
+bool batadv_forw_packet_steal(struct batadv_forw_packet *forw_packet,
+			      spinlock_t *lock)
+{
+	/* did purging routine steal it earlier? */
+	spin_lock_bh(lock);
+	if (batadv_forw_packet_was_stolen(forw_packet)) {
+		spin_unlock_bh(lock);
+		return false;
+	}
+
+	hlist_del_init(&forw_packet->list);
+
+	/* Just to spot misuse of this function */
+	hlist_add_fake(&forw_packet->cleanup_list);
+
+	spin_unlock_bh(lock);
+	return true;
+}
+
+/**
+ * batadv_forw_packet_list_steal - claim a list of forward packets for free()
+ * @forw_list: the to be stolen forward packets
+ * @cleanup_list: a backup pointer, to be able to dispose the packet later
+ * @hard_iface: the interface to steal forward packets from
+ *
+ * This function claims responsibility to free any forw_packet queued on the
+ * given hard_iface. If hard_iface is NULL forwarding packets on all hard
+ * interfaces will be claimed.
+ *
+ * The packets are being moved from the forw_list to the cleanup_list and
+ * by that allows already running threads to notice the claiming.
+ */
 static void
-_batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv,
-				 struct batadv_forw_packet *forw_packet,
-				 unsigned long send_time)
+batadv_forw_packet_list_steal(struct hlist_head *forw_list,
+			      struct hlist_head *cleanup_list,
+			      const struct batadv_hard_iface *hard_iface)
 {
-	/* add new packet to packet list */
-	spin_lock_bh(&bat_priv->forw_bcast_list_lock);
-	hlist_add_head(&forw_packet->list, &bat_priv->forw_bcast_list);
-	spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
+	struct batadv_forw_packet *forw_packet;
+	struct hlist_node *safe_tmp_node;
+
+	hlist_for_each_entry_safe(forw_packet, safe_tmp_node,
+				  forw_list, list) {
+		/* if purge_outstanding_packets() was called with an argument
+		 * we delete only packets belonging to the given interface
+		 */
+		if (hard_iface &&
+		    (forw_packet->if_incoming != hard_iface) &&
+		    (forw_packet->if_outgoing != hard_iface))
+			continue;
+
+		hlist_del(&forw_packet->list);
+		hlist_add_head(&forw_packet->cleanup_list, cleanup_list);
+	}
+}
+
+/**
+ * batadv_forw_packet_list_free - free a list of forward packets
+ * @head: a list of to be freed forw_packets
+ *
+ * This function cancels the scheduling of any packet in the provided list,
+ * waits for any possibly running packet forwarding thread to finish and
+ * finally, safely frees this forward packet.
+ *
+ * This function might sleep.
+ */
+static void batadv_forw_packet_list_free(struct hlist_head *head)
+{
+	struct batadv_forw_packet *forw_packet;
+	struct hlist_node *safe_tmp_node;
+
+	hlist_for_each_entry_safe(forw_packet, safe_tmp_node, head,
+				  cleanup_list) {
+		cancel_delayed_work_sync(&forw_packet->delayed_work);
 
-	/* start timer for this packet */
-	queue_delayed_work(batadv_event_workqueue, &forw_packet->delayed_work,
-			   send_time);
+		hlist_del(&forw_packet->cleanup_list);
+		batadv_forw_packet_free(forw_packet, true);
+	}
+}
+
+/**
+ * batadv_forw_packet_queue - try to queue a forwarding packet
+ * @forw_packet: the forwarding packet to queue
+ * @lock: a key to the store (e.g. forw_{bat,bcast}_list_lock)
+ * @head: the shelve to queue it on (e.g. forw_{bat,bcast}_list)
+ * @send_time: timestamp (jiffies) when the packet is to be sent
+ *
+ * This function tries to (re)queue a forwarding packet. Requeuing
+ * is prevented if the according interface is shutting down
+ * (e.g. if batadv_forw_packet_list_steal() was called for this
+ * packet earlier).
+ *
+ * Calling batadv_forw_packet_queue() after a call to
+ * batadv_forw_packet_steal() is forbidden!
+ *
+ * Caller needs to ensure that forw_packet->delayed_work was initialized.
+ */
+static void batadv_forw_packet_queue(struct batadv_forw_packet *forw_packet,
+				     spinlock_t *lock, struct hlist_head *head,
+				     unsigned long send_time)
+{
+	spin_lock_bh(lock);
+
+	/* did purging routine steal it from us? */
+	if (batadv_forw_packet_was_stolen(forw_packet)) {
+		/* If you got it for free() without trouble, then
+		 * don't get back into the queue after stealing...
+		 */
+		WARN_ONCE(hlist_fake(&forw_packet->cleanup_list),
+			  "Requeuing after batadv_forw_packet_steal() not allowed!\n");
+
+		spin_unlock_bh(lock);
+		return;
+	}
+
+	hlist_del_init(&forw_packet->list);
+	hlist_add_head(&forw_packet->list, head);
+
+	queue_delayed_work(batadv_event_workqueue,
+			   &forw_packet->delayed_work,
+			   send_time - jiffies);
+	spin_unlock_bh(lock);
+}
+
+/**
+ * batadv_forw_packet_bcast_queue - try to queue a broadcast packet
+ * @bat_priv: the bat priv with all the soft interface information
+ * @forw_packet: the forwarding packet to queue
+ * @send_time: timestamp (jiffies) when the packet is to be sent
+ *
+ * This function tries to (re)queue a broadcast packet.
+ *
+ * Caller needs to ensure that forw_packet->delayed_work was initialized.
+ */
+static void
+batadv_forw_packet_bcast_queue(struct batadv_priv *bat_priv,
+			       struct batadv_forw_packet *forw_packet,
+			       unsigned long send_time)
+{
+	batadv_forw_packet_queue(forw_packet, &bat_priv->forw_bcast_list_lock,
+				 &bat_priv->forw_bcast_list, send_time);
+}
+
+/**
+ * batadv_forw_packet_ogmv1_queue - try to queue an OGMv1 packet
+ * @bat_priv: the bat priv with all the soft interface information
+ * @forw_packet: the forwarding packet to queue
+ * @send_time: timestamp (jiffies) when the packet is to be sent
+ *
+ * This function tries to (re)queue an OGMv1 packet.
+ *
+ * Caller needs to ensure that forw_packet->delayed_work was initialized.
+ */
+void batadv_forw_packet_ogmv1_queue(struct batadv_priv *bat_priv,
+				    struct batadv_forw_packet *forw_packet,
+				    unsigned long send_time)
+{
+	batadv_forw_packet_queue(forw_packet, &bat_priv->forw_bat_list_lock,
+				 &bat_priv->forw_bat_list, send_time);
 }
 
 /**
@@ -600,7 +775,7 @@ int batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv,
 	INIT_DELAYED_WORK(&forw_packet->delayed_work,
 			  batadv_send_outstanding_bcast_packet);
 
-	_batadv_add_bcast_packet_to_list(bat_priv, forw_packet, delay);
+	batadv_forw_packet_bcast_queue(bat_priv, forw_packet, jiffies + delay);
 	return NETDEV_TX_OK;
 
 err_packet_free:
@@ -619,6 +794,7 @@ static void batadv_send_outstanding_bcast_packet(struct work_struct *work)
 	struct sk_buff *skb1;
 	struct net_device *soft_iface;
 	struct batadv_priv *bat_priv;
+	unsigned long send_time = jiffies + msecs_to_jiffies(5);
 	bool dropped = false;
 	u8 *neigh_addr;
 	u8 *orig_neigh;
@@ -630,10 +806,6 @@ static void batadv_send_outstanding_bcast_packet(struct work_struct *work)
 	soft_iface = forw_packet->if_incoming->soft_iface;
 	bat_priv = netdev_priv(soft_iface);
 
-	spin_lock_bh(&bat_priv->forw_bcast_list_lock);
-	hlist_del(&forw_packet->list);
-	spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
-
 	if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING) {
 		dropped = true;
 		goto out;
@@ -714,22 +886,34 @@ static void batadv_send_outstanding_bcast_packet(struct work_struct *work)
 
 	/* if we still have some more bcasts to send */
 	if (forw_packet->num_packets < BATADV_NUM_BCASTS_MAX) {
-		_batadv_add_bcast_packet_to_list(bat_priv, forw_packet,
-						 msecs_to_jiffies(5));
+		batadv_forw_packet_bcast_queue(bat_priv, forw_packet,
+					       send_time);
 		return;
 	}
 
 out:
-	batadv_forw_packet_free(forw_packet, dropped);
+	/* do we get something for free()? */
+	if (batadv_forw_packet_steal(forw_packet,
+				     &bat_priv->forw_bcast_list_lock))
+		batadv_forw_packet_free(forw_packet, dropped);
 }
 
+/**
+ * batadv_purge_outstanding_packets - stop/purge scheduled bcast/OGMv1 packets
+ * @bat_priv: the bat priv with all the soft interface information
+ * @hard_iface: the hard interface to cancel and purge bcast/ogm packets on
+ *
+ * This method cancels and purges any broadcast and OGMv1 packet on the given
+ * hard_iface. If hard_iface is NULL, broadcast and OGMv1 packets on all hard
+ * interfaces will be canceled and purged.
+ *
+ * This function might sleep.
+ */
 void
 batadv_purge_outstanding_packets(struct batadv_priv *bat_priv,
 				 const struct batadv_hard_iface *hard_iface)
 {
-	struct batadv_forw_packet *forw_packet;
-	struct hlist_node *safe_tmp_node;
-	bool pending;
+	struct hlist_head head = HLIST_HEAD_INIT;
 
 	if (hard_iface)
 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
@@ -739,57 +923,18 @@ batadv_purge_outstanding_packets(struct batadv_priv *bat_priv,
 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 			   "purge_outstanding_packets()\n");
 
-	/* free bcast list */
+	/* claim bcast list for free() */
 	spin_lock_bh(&bat_priv->forw_bcast_list_lock);
-	hlist_for_each_entry_safe(forw_packet, safe_tmp_node,
-				  &bat_priv->forw_bcast_list, list) {
-		/* if purge_outstanding_packets() was called with an argument
-		 * we delete only packets belonging to the given interface
-		 */
-		if ((hard_iface) &&
-		    (forw_packet->if_incoming != hard_iface) &&
-		    (forw_packet->if_outgoing != hard_iface))
-			continue;
-
-		spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
-
-		/* batadv_send_outstanding_bcast_packet() will lock the list to
-		 * delete the item from the list
-		 */
-		pending = cancel_delayed_work_sync(&forw_packet->delayed_work);
-		spin_lock_bh(&bat_priv->forw_bcast_list_lock);
-
-		if (pending) {
-			hlist_del(&forw_packet->list);
-			batadv_forw_packet_free(forw_packet, true);
-		}
-	}
+	batadv_forw_packet_list_steal(&bat_priv->forw_bcast_list, &head,
+				      hard_iface);
 	spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
 
-	/* free batman packet list */
+	/* claim batman packet list for free() */
 	spin_lock_bh(&bat_priv->forw_bat_list_lock);
-	hlist_for_each_entry_safe(forw_packet, safe_tmp_node,
-				  &bat_priv->forw_bat_list, list) {
-		/* if purge_outstanding_packets() was called with an argument
-		 * we delete only packets belonging to the given interface
-		 */
-		if ((hard_iface) &&
-		    (forw_packet->if_incoming != hard_iface) &&
-		    (forw_packet->if_outgoing != hard_iface))
-			continue;
-
-		spin_unlock_bh(&bat_priv->forw_bat_list_lock);
-
-		/* send_outstanding_bat_packet() will lock the list to
-		 * delete the item from the list
-		 */
-		pending = cancel_delayed_work_sync(&forw_packet->delayed_work);
-		spin_lock_bh(&bat_priv->forw_bat_list_lock);
-
-		if (pending) {
-			hlist_del(&forw_packet->list);
-			batadv_forw_packet_free(forw_packet, true);
-		}
-	}
+	batadv_forw_packet_list_steal(&bat_priv->forw_bat_list, &head,
+				      hard_iface);
 	spin_unlock_bh(&bat_priv->forw_bat_list_lock);
+
+	/* then cancel or wait for packet workers to finish and free */
+	batadv_forw_packet_list_free(&head);
 }
diff --git a/net/batman-adv/send.h b/net/batman-adv/send.h
index c580194..a94e1e8 100644
--- a/net/batman-adv/send.h
+++ b/net/batman-adv/send.h
@@ -21,6 +21,7 @@
 #include "main.h"
 
 #include <linux/compiler.h>
+#include <linux/spinlock.h>
 #include <linux/types.h>
 
 #include "packet.h"
@@ -34,6 +35,10 @@ batadv_forw_packet_alloc(struct batadv_hard_iface *if_incoming,
 			 struct batadv_hard_iface *if_outgoing,
 			 atomic_t *queue_left,
 			 struct batadv_priv *bat_priv);
+bool batadv_forw_packet_steal(struct batadv_forw_packet *packet, spinlock_t *l);
+void batadv_forw_packet_ogmv1_queue(struct batadv_priv *bat_priv,
+				    struct batadv_forw_packet *forw_packet,
+				    unsigned long send_time);
 
 int batadv_send_skb_to_orig(struct sk_buff *skb,
 			    struct batadv_orig_node *orig_node,
diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h
index caa00a5..e913aee 100644
--- a/net/batman-adv/types.h
+++ b/net/batman-adv/types.h
@@ -1385,6 +1385,7 @@ struct batadv_skb_cb {
 /**
  * struct batadv_forw_packet - structure for bcast packets to be sent/forwarded
  * @list: list node for batadv_priv::forw_{bat,bcast}_list
+ * @cleanup_list: list node for purging functions
  * @send_time: execution time for delayed_work (packet sending)
  * @own: bool for locally generated packets (local OGMs are re-scheduled after
  *  sending)
@@ -1401,6 +1402,7 @@ struct batadv_skb_cb {
  */
 struct batadv_forw_packet {
 	struct hlist_node list;
+	struct hlist_node cleanup_list;
 	unsigned long send_time;
 	u8 own;
 	struct sk_buff *skb;
-- 
2.10.2

Re: [B.A.T.M.A.N.] [PATCH 0/8] pull request for net-next: batman-adv 2016-11-19

[David Miller]

From: Simon Wunderlich <sw@simonwunderlich.de>
Date: Sat, 19 Nov 2016 14:35:20 +0100

> this should be our last feature pull request for batman-adv in this round.
> 
> Please pull or let me know of any problem!

Also pulled, thanks.