cfg80211/mac80211: add mesh join/leave commands

Instead of tying mesh activity to interface up,
add join and leave commands for mesh. Since we
must be backward compatible, let cfg80211 handle
joining a mesh if a mesh ID was pre-configured
when the device goes up.

Note that this therefore must modify mac80211 as
well since mac80211 needs to lose the logic to
start the mesh on interface up.

We now allow querying mesh parameters before the
mesh is connected, which simply returns defaults.
Setting them (internally renamed to "update") is
only allowed while connected. Specify them with
the new mesh join command instead where needed.

In mac80211, beaconing must now also follow the
mesh enabled/not enabled state, which is done
by testing the mesh ID.
Signed-off-by: Javier Cardona <javier@cozybit.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

include/linux/nl80211.h

@@ -394,6 +394,11 @@
  *
  * @NL80211_CMD_SET_WDS_PEER: Set the MAC address of the peer on a WDS interface.
  *
+ * @NL80211_CMD_JOIN_MESH: Join a mesh. The mesh ID must be given, and initial
+ *	mesh config parameters may be given.
+ * @NL80211_CMD_LEAVE_MESH: Leave the mesh network -- no special arguments, the
+ *	network is determined by the network interface.
+ *
  * @NL80211_CMD_MAX: highest used command number
  * @__NL80211_CMD_AFTER_LAST: internal use
  */
@@ -500,6 +505,9 @@ enum nl80211_commands {
 
 	NL80211_CMD_FRAME_WAIT_CANCEL,
 
+	NL80211_CMD_JOIN_MESH,
+	NL80211_CMD_LEAVE_MESH,
+
 	/* add new commands above here */
 
 	/* used to define NL80211_CMD_MAX below */

include/net/cfg80211.h

@@ -258,13 +258,9 @@ struct ieee80211_supported_band {
 
 /**
  * struct vif_params - describes virtual interface parameters
- * @mesh_id: mesh ID to use
- * @mesh_id_len: length of the mesh ID
  * @use_4addr: use 4-address frames
  */
 struct vif_params {
-       u8 *mesh_id;
-       int mesh_id_len;
        int use_4addr;
 };
 
@@ -615,6 +611,11 @@ struct bss_parameters {
 	int ap_isolate;
 };
 
+/*
+ * struct mesh_config - 802.11s mesh configuration
+ *
+ * These parameters can be changed while the mesh is active.
+ */
 struct mesh_config {
 	/* Timeouts in ms */
 	/* Mesh plink management parameters */
@@ -637,6 +638,18 @@ struct mesh_config {
 	u8  dot11MeshHWMPRootMode;
 };
 
+/**
+ * struct mesh_setup - 802.11s mesh setup configuration
+ * @mesh_id: the mesh ID
+ * @mesh_id_len: length of the mesh ID, at least 1 and at most 32 bytes
+ *
+ * These parameters are fixed when the mesh is created.
+ */
+struct mesh_setup {
+	const u8 *mesh_id;
+	u8 mesh_id_len;
+};
+
 /**
  * struct ieee80211_txq_params - TX queue parameters
  * @queue: TX queue identifier (NL80211_TXQ_Q_*)
@@ -1078,7 +1091,7 @@ struct cfg80211_pmksa {
  *
  * @get_mesh_params: Put the current mesh parameters into *params
  *
- * @set_mesh_params: Set mesh parameters.
+ * @update_mesh_params: Update mesh parameters on a running mesh.
  *	The mask is a bitfield which tells us which parameters to
  *	set, and which to leave alone.
  *
@@ -1229,9 +1242,14 @@ struct cfg80211_ops {
 	int	(*get_mesh_params)(struct wiphy *wiphy,
 				struct net_device *dev,
 				struct mesh_config *conf);
-	int	(*set_mesh_params)(struct wiphy *wiphy,
-				struct net_device *dev,
-				const struct mesh_config *nconf, u32 mask);
+	int	(*update_mesh_params)(struct wiphy *wiphy,
+				      struct net_device *dev, u32 mask,
+				      const struct mesh_config *nconf);
+	int	(*join_mesh)(struct wiphy *wiphy, struct net_device *dev,
+			     const struct mesh_config *conf,
+			     const struct mesh_setup *setup);
+	int	(*leave_mesh)(struct wiphy *wiphy, struct net_device *dev);
+
 	int	(*change_bss)(struct wiphy *wiphy, struct net_device *dev,
 			      struct bss_parameters *params);
 
@@ -1647,6 +1665,8 @@ struct cfg80211_cached_keys;
  * @bssid: (private) Used by the internal configuration code
  * @ssid: (private) Used by the internal configuration code
  * @ssid_len: (private) Used by the internal configuration code
+ * @mesh_id_len: (private) Used by the internal configuration code
+ * @mesh_id_up_len: (private) Used by the internal configuration code
  * @wext: (private) Used by the internal wireless extensions compat code
  * @use_4addr: indicates 4addr mode is used on this interface, must be
  *	set by driver (if supported) on add_interface BEFORE registering the
@@ -1676,7 +1696,7 @@ struct wireless_dev {
 
 	/* currently used for IBSS and SME - might be rearranged later */
 	u8 ssid[IEEE80211_MAX_SSID_LEN];
-	u8 ssid_len;
+	u8 ssid_len, mesh_id_len, mesh_id_up_len;
 	enum {
 		CFG80211_SME_IDLE,
 		CFG80211_SME_CONNECTING,

net/mac80211/cfg.c

@@ -60,11 +60,6 @@ static int ieee80211_change_iface(struct wiphy *wiphy,
 	if (ret)
 		return ret;
 
-	if (ieee80211_vif_is_mesh(&sdata->vif) && params->mesh_id_len)
-		ieee80211_sdata_set_mesh_id(sdata,
-					    params->mesh_id_len,
-					    params->mesh_id);
-
 	if (type == NL80211_IFTYPE_AP_VLAN &&
 	    params && params->use_4addr == 0)
 		rcu_assign_pointer(sdata->u.vlan.sta, NULL);
@@ -1003,9 +998,9 @@ static inline bool _chg_mesh_attr(enum nl80211_meshconf_params parm, u32 mask)
 	return (mask >> (parm-1)) & 0x1;
 }
 
-static int ieee80211_set_mesh_params(struct wiphy *wiphy,
-				struct net_device *dev,
-				const struct mesh_config *nconf, u32 mask)
+static int ieee80211_update_mesh_params(struct wiphy *wiphy,
+					struct net_device *dev, u32 mask,
+					const struct mesh_config *nconf)
 {
 	struct mesh_config *conf;
 	struct ieee80211_sub_if_data *sdata;
@@ -1056,6 +1051,30 @@ static int ieee80211_set_mesh_params(struct wiphy *wiphy,
 	return 0;
 }
 
+static int ieee80211_join_mesh(struct wiphy *wiphy, struct net_device *dev,
+			       const struct mesh_config *conf,
+			       const struct mesh_setup *setup)
+{
+	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+
+	memcpy(&sdata->u.mesh.mshcfg, conf, sizeof(struct mesh_config));
+	ifmsh->mesh_id_len = setup->mesh_id_len;
+	memcpy(ifmsh->mesh_id, setup->mesh_id, ifmsh->mesh_id_len);
+
+	ieee80211_start_mesh(sdata);
+
+	return 0;
+}
+
+static int ieee80211_leave_mesh(struct wiphy *wiphy, struct net_device *dev)
+{
+	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+
+	ieee80211_stop_mesh(sdata);
+
+	return 0;
+}
 #endif
 
 static int ieee80211_change_bss(struct wiphy *wiphy,
@@ -1760,8 +1779,10 @@ struct cfg80211_ops mac80211_config_ops = {
 	.change_mpath = ieee80211_change_mpath,
 	.get_mpath = ieee80211_get_mpath,
 	.dump_mpath = ieee80211_dump_mpath,
-	.set_mesh_params = ieee80211_set_mesh_params,
+	.update_mesh_params = ieee80211_update_mesh_params,
 	.get_mesh_params = ieee80211_get_mesh_params,
+	.join_mesh = ieee80211_join_mesh,
+	.leave_mesh = ieee80211_leave_mesh,
 #endif
 	.change_bss = ieee80211_change_bss,
 	.set_txq_params = ieee80211_set_txq_params,

net/mac80211/ieee80211_i.h

@@ -609,19 +609,6 @@ struct ieee80211_sub_if_data *vif_to_sdata(struct ieee80211_vif *p)
 	return container_of(p, struct ieee80211_sub_if_data, vif);
 }
 
-static inline void
-ieee80211_sdata_set_mesh_id(struct ieee80211_sub_if_data *sdata,
-			    u8 mesh_id_len, u8 *mesh_id)
-{
-#ifdef CONFIG_MAC80211_MESH
-	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
-	ifmsh->mesh_id_len = mesh_id_len;
-	memcpy(ifmsh->mesh_id, mesh_id, mesh_id_len);
-#else
-	WARN_ON(1);
-#endif
-}
-
 enum sdata_queue_type {
 	IEEE80211_SDATA_QUEUE_TYPE_FRAME	= 0,
 	IEEE80211_SDATA_QUEUE_AGG_START		= 1,

net/mac80211/iface.c

@@ -268,9 +268,7 @@ static int ieee80211_do_open(struct net_device *dev, bool coming_up)
 				goto err_stop;
 		}
 
-		if (ieee80211_vif_is_mesh(&sdata->vif)) {
-			ieee80211_start_mesh(sdata);
-		} else if (sdata->vif.type == NL80211_IFTYPE_AP) {
+		if (sdata->vif.type == NL80211_IFTYPE_AP) {
 			local->fif_pspoll++;
 			local->fif_probe_req++;
 
@@ -495,10 +493,6 @@ static void ieee80211_do_stop(struct ieee80211_sub_if_data *sdata,
 		ieee80211_adjust_monitor_flags(sdata, -1);
 		ieee80211_configure_filter(local);
 		break;
-	case NL80211_IFTYPE_MESH_POINT:
-		if (ieee80211_vif_is_mesh(&sdata->vif))
-			ieee80211_stop_mesh(sdata);
-		/* fall through */
 	default:
 		flush_work(&sdata->work);
 		/*
@@ -1188,12 +1182,6 @@ int ieee80211_if_add(struct ieee80211_local *local, const char *name,
 	if (ret)
 		goto fail;
 
-	if (ieee80211_vif_is_mesh(&sdata->vif) &&
-	    params && params->mesh_id_len)
-		ieee80211_sdata_set_mesh_id(sdata,
-					    params->mesh_id_len,
-					    params->mesh_id);
-
 	mutex_lock(&local->iflist_mtx);
 	list_add_tail_rcu(&sdata->list, &local->interfaces);
 	mutex_unlock(&local->iflist_mtx);

net/mac80211/main.c

@@ -246,7 +246,8 @@ void ieee80211_bss_info_change_notify(struct ieee80211_sub_if_data *sdata,
 					!!sdata->u.ibss.presp;
 				break;
 			case NL80211_IFTYPE_MESH_POINT:
-				sdata->vif.bss_conf.enable_beacon = true;
+				sdata->vif.bss_conf.enable_beacon =
+					!!sdata->u.mesh.mesh_id_len;
 				break;
 			default:
 				/* not reached */

net/mac80211/mesh.c

@@ -530,6 +530,11 @@ void ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
 {
 	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+
+	ifmsh->mesh_id_len = 0;
+	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
+	sta_info_flush(local, NULL);
 
 	del_timer_sync(&sdata->u.mesh.housekeeping_timer);
 	del_timer_sync(&sdata->u.mesh.mesh_path_root_timer);
@@ -674,27 +679,6 @@ void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
 		    ieee80211_mesh_housekeeping_timer,
 		    (unsigned long) sdata);
 
-	ifmsh->mshcfg.dot11MeshRetryTimeout = MESH_RET_T;
-	ifmsh->mshcfg.dot11MeshConfirmTimeout = MESH_CONF_T;
-	ifmsh->mshcfg.dot11MeshHoldingTimeout = MESH_HOLD_T;
-	ifmsh->mshcfg.dot11MeshMaxRetries = MESH_MAX_RETR;
-	ifmsh->mshcfg.dot11MeshTTL = MESH_TTL;
-	ifmsh->mshcfg.element_ttl = MESH_DEFAULT_ELEMENT_TTL;
-	ifmsh->mshcfg.auto_open_plinks = true;
-	ifmsh->mshcfg.dot11MeshMaxPeerLinks =
-		MESH_MAX_ESTAB_PLINKS;
-	ifmsh->mshcfg.dot11MeshHWMPactivePathTimeout =
-		MESH_PATH_TIMEOUT;
-	ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval =
-		MESH_PREQ_MIN_INT;
-	ifmsh->mshcfg.dot11MeshHWMPnetDiameterTraversalTime =
-		MESH_DIAM_TRAVERSAL_TIME;
-	ifmsh->mshcfg.dot11MeshHWMPmaxPREQretries =
-		MESH_MAX_PREQ_RETRIES;
-	ifmsh->mshcfg.path_refresh_time =
-		MESH_PATH_REFRESH_TIME;
-	ifmsh->mshcfg.min_discovery_timeout =
-		MESH_MIN_DISCOVERY_TIMEOUT;
 	ifmsh->accepting_plinks = true;
 	ifmsh->preq_id = 0;
 	ifmsh->sn = 0;

net/mac80211/mesh.h

@@ -175,33 +175,10 @@ struct mesh_rmc {
  */
 #define MESH_CFG_CMP_LEN 	(IEEE80211_MESH_CONFIG_LEN - 2)
 
-/* Default values, timeouts in ms */
-#define MESH_TTL 		31
-#define MESH_MAX_RETR	 	3
-#define MESH_RET_T 		100
-#define MESH_CONF_T 		100
-#define MESH_HOLD_T 		100
-
-#define MESH_PATH_TIMEOUT	5000
-/* Minimum interval between two consecutive PREQs originated by the same
- * interface
- */
-#define MESH_PREQ_MIN_INT	10
-#define MESH_DIAM_TRAVERSAL_TIME 50
-/* A path will be refreshed if it is used PATH_REFRESH_TIME milliseconds before
- * timing out.  This way it will remain ACTIVE and no data frames will be
- * unnecesarily held in the pending queue.
- */
-#define MESH_PATH_REFRESH_TIME			1000
-#define MESH_MIN_DISCOVERY_TIMEOUT (2 * MESH_DIAM_TRAVERSAL_TIME)
 #define MESH_DEFAULT_BEACON_INTERVAL		1000 	/* in 1024 us units */
 
-#define MESH_MAX_PREQ_RETRIES 4
 #define MESH_PATH_EXPIRE (600 * HZ)
 
-/* Default maximum number of established plinks per interface */
-#define MESH_MAX_ESTAB_PLINKS	32
-
 /* Default maximum number of plinks per interface */
 #define MESH_MAX_PLINKS		256
 
@@ -216,8 +193,6 @@ struct mesh_rmc {
 #define PERR_RCODE_NO_ROUTE     12
 #define PERR_RCODE_DEST_UNREACH 13
 
-#define MESH_DEFAULT_ELEMENT_TTL 31
-
 /* Public interfaces */
 /* Various */
 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,

net/wireless/Makefile

@@ -10,7 +10,7 @@ obj-$(CONFIG_WEXT_SPY) += wext-spy.o
 obj-$(CONFIG_WEXT_PRIV) += wext-priv.o
 
 cfg80211-y += core.o sysfs.o radiotap.o util.o reg.o scan.o nl80211.o
-cfg80211-y += mlme.o ibss.o sme.o chan.o ethtool.o
+cfg80211-y += mlme.o ibss.o sme.o chan.o ethtool.o mesh.o
 cfg80211-$(CONFIG_CFG80211_DEBUGFS) += debugfs.o
 cfg80211-$(CONFIG_CFG80211_WEXT) += wext-compat.o wext-sme.o
 cfg80211-$(CONFIG_CFG80211_INTERNAL_REGDB) += regdb.o

net/wireless/core.c

@@ -332,6 +332,7 @@ struct wiphy *wiphy_new(const struct cfg80211_ops *ops, int sizeof_priv)
 	WARN_ON(ops->add_virtual_intf && !ops->del_virtual_intf);
 	WARN_ON(ops->add_station && !ops->del_station);
 	WARN_ON(ops->add_mpath && !ops->del_mpath);
+	WARN_ON(ops->join_mesh && !ops->leave_mesh);
 
 	alloc_size = sizeof(*rdev) + sizeof_priv;
 
@@ -752,6 +753,9 @@ static int cfg80211_netdev_notifier_call(struct notifier_block * nb,
 			cfg80211_mlme_down(rdev, dev);
 			wdev_unlock(wdev);
 			break;
+		case NL80211_IFTYPE_MESH_POINT:
+			cfg80211_leave_mesh(rdev, dev);
+			break;
 		default:
 			break;
 		}
@@ -775,20 +779,27 @@ static int cfg80211_netdev_notifier_call(struct notifier_block * nb,
 		}
 		cfg80211_lock_rdev(rdev);
 		mutex_lock(&rdev->devlist_mtx);
-#ifdef CONFIG_CFG80211_WEXT
 		wdev_lock(wdev);
 		switch (wdev->iftype) {
+#ifdef CONFIG_CFG80211_WEXT
 		case NL80211_IFTYPE_ADHOC:
 			cfg80211_ibss_wext_join(rdev, wdev);
 			break;
 		case NL80211_IFTYPE_STATION:
 			cfg80211_mgd_wext_connect(rdev, wdev);
 			break;
+#endif
+		case NL80211_IFTYPE_MESH_POINT:
+			/* backward compat code ... */
+			if (wdev->mesh_id_up_len)
+				__cfg80211_join_mesh(rdev, dev, wdev->ssid,
+						     wdev->mesh_id_up_len,
+						     &default_mesh_config);
+			break;
 		default:
 			break;
 		}
 		wdev_unlock(wdev);
-#endif
 		rdev->opencount++;
 		mutex_unlock(&rdev->devlist_mtx);
 		cfg80211_unlock_rdev(rdev);

net/wireless/core.h

@@ -285,6 +285,19 @@ void __cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid);
 int cfg80211_ibss_wext_join(struct cfg80211_registered_device *rdev,
 			    struct wireless_dev *wdev);
 
+/* mesh */
+extern const struct mesh_config default_mesh_config;
+int __cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
+			 struct net_device *dev,
+			 const u8 *mesh_id, u8 mesh_id_len,
+			 const struct mesh_config *conf);
+int cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
+		       struct net_device *dev,
+		       const u8 *mesh_id, u8 mesh_id_len,
+		       const struct mesh_config *conf);
+int cfg80211_leave_mesh(struct cfg80211_registered_device *rdev,
+			struct net_device *dev);
+
 /* MLME */
 int __cfg80211_mlme_auth(struct cfg80211_registered_device *rdev,
 			 struct net_device *dev,

net/wireless/mesh.c

+#include <linux/ieee80211.h>
+#include <net/cfg80211.h>
+#include "core.h"
+
+/* Default values, timeouts in ms */
+#define MESH_TTL 		31
+#define MESH_DEFAULT_ELEMENT_TTL 31
+#define MESH_MAX_RETR	 	3
+#define MESH_RET_T 		100
+#define MESH_CONF_T 		100
+#define MESH_HOLD_T 		100
+
+#define MESH_PATH_TIMEOUT	5000
+
+/*
+ * Minimum interval between two consecutive PREQs originated by the same
+ * interface
+ */
+#define MESH_PREQ_MIN_INT	10
+#define MESH_DIAM_TRAVERSAL_TIME 50
+
+/*
+ * A path will be refreshed if it is used PATH_REFRESH_TIME milliseconds
+ * before timing out.  This way it will remain ACTIVE and no data frames
+ * will be unnecessarily held in the pending queue.
+ */
+#define MESH_PATH_REFRESH_TIME			1000
+#define MESH_MIN_DISCOVERY_TIMEOUT (2 * MESH_DIAM_TRAVERSAL_TIME)
+
+/* Default maximum number of established plinks per interface */
+#define MESH_MAX_ESTAB_PLINKS	32
+
+#define MESH_MAX_PREQ_RETRIES	4
+
+
+const struct mesh_config default_mesh_config = {
+	.dot11MeshRetryTimeout = MESH_RET_T,
+	.dot11MeshConfirmTimeout = MESH_CONF_T,
+	.dot11MeshHoldingTimeout = MESH_HOLD_T,
+	.dot11MeshMaxRetries = MESH_MAX_RETR,
+	.dot11MeshTTL = MESH_TTL,
+	.element_ttl = MESH_DEFAULT_ELEMENT_TTL,
+	.auto_open_plinks = true,
+	.dot11MeshMaxPeerLinks = MESH_MAX_ESTAB_PLINKS,
+	.dot11MeshHWMPactivePathTimeout = MESH_PATH_TIMEOUT,
+	.dot11MeshHWMPpreqMinInterval = MESH_PREQ_MIN_INT,
+	.dot11MeshHWMPnetDiameterTraversalTime = MESH_DIAM_TRAVERSAL_TIME,
+	.dot11MeshHWMPmaxPREQretries = MESH_MAX_PREQ_RETRIES,
+	.path_refresh_time = MESH_PATH_REFRESH_TIME,
+	.min_discovery_timeout = MESH_MIN_DISCOVERY_TIMEOUT,
+};
+
+
+int __cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
+			 struct net_device *dev,
+			 const u8 *mesh_id, u8 mesh_id_len,
+			 const struct mesh_config *conf)
+{
+	struct wireless_dev *wdev = dev->ieee80211_ptr;
+	struct mesh_setup setup = {
+		.mesh_id = mesh_id,
+		.mesh_id_len = mesh_id_len,
+	};
+	int err;
+
+	BUILD_BUG_ON(IEEE80211_MAX_SSID_LEN != IEEE80211_MAX_MESH_ID_LEN);
+
+	ASSERT_WDEV_LOCK(wdev);
+
+	if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_MESH_POINT)
+		return -EOPNOTSUPP;
+
+	if (wdev->mesh_id_len)
+		return -EALREADY;
+
+	if (!mesh_id_len)
+		return -EINVAL;
+
+	if (!rdev->ops->join_mesh)
+		return -EOPNOTSUPP;
+
+	err = rdev->ops->join_mesh(&rdev->wiphy, dev, conf, &setup);
+	if (!err) {
+		memcpy(wdev->ssid, mesh_id, mesh_id_len);
+		wdev->mesh_id_len = mesh_id_len;
+	}
+
+	return err;
+}
+
+int cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
+		       struct net_device *dev,
+		       const u8 *mesh_id, u8 mesh_id_len,
+		       const struct mesh_config *conf)
+{
+	struct wireless_dev *wdev = dev->ieee80211_ptr;
+	int err;
+
+	wdev_lock(wdev);
+	err = __cfg80211_join_mesh(rdev, dev, mesh_id, mesh_id_len, conf);
+	wdev_unlock(wdev);
+
+	return err;
+}
+
+static int __cfg80211_leave_mesh(struct cfg80211_registered_device *rdev,
+				 struct net_device *dev)
+{
+	struct wireless_dev *wdev = dev->ieee80211_ptr;
+	int err;
+
+	ASSERT_WDEV_LOCK(wdev);
+
+	if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_MESH_POINT)
+		return -EOPNOTSUPP;
+
+	if (!rdev->ops->leave_mesh)
+		return -EOPNOTSUPP;
+
+	if (!wdev->mesh_id_len)
+		return -ENOTCONN;
+
+	err = rdev->ops->leave_mesh(&rdev->wiphy, dev);
+	if (!err)
+		wdev->mesh_id_len = 0;
+	return err;
+}
+
+int cfg80211_leave_mesh(struct cfg80211_registered_device *rdev,
+			struct net_device *dev)
+{
+	struct wireless_dev *wdev = dev->ieee80211_ptr;
+	int err;
+
+	wdev_lock(wdev);
+	err = __cfg80211_leave_mesh(rdev, dev);
+	wdev_unlock(wdev);
+
+	return err;
+}

net/wireless/nl80211.c

@@ -661,13 +661,14 @@ static int nl80211_send_wiphy(struct sk_buff *msg, u32 pid, u32 seq, int flags,
 	CMD(add_beacon, NEW_BEACON);
 	CMD(add_station, NEW_STATION);
 	CMD(add_mpath, NEW_MPATH);
-	CMD(set_mesh_params, SET_MESH_PARAMS);
+	CMD(update_mesh_params, SET_MESH_PARAMS);
 	CMD(change_bss, SET_BSS);
 	CMD(auth, AUTHENTICATE);
 	CMD(assoc, ASSOCIATE);
 	CMD(deauth, DEAUTHENTICATE);
 	CMD(disassoc, DISASSOCIATE);
 	CMD(join_ibss, JOIN_IBSS);
+	CMD(join_mesh, JOIN_MESH);
 	CMD(set_pmksa, SET_PMKSA);
 	CMD(del_pmksa, DEL_PMKSA);
 	CMD(flush_pmksa, FLUSH_PMKSA);
@@ -1324,11 +1325,21 @@ static int nl80211_set_interface(struct sk_buff *skb, struct genl_info *info)
 	}
 
 	if (info->attrs[NL80211_ATTR_MESH_ID]) {
+		struct wireless_dev *wdev = dev->ieee80211_ptr;
+
 		if (ntype != NL80211_IFTYPE_MESH_POINT)
 			return -EINVAL;
-		params.mesh_id = nla_data(info->attrs[NL80211_ATTR_MESH_ID]);
-		params.mesh_id_len = nla_len(info->attrs[NL80211_ATTR_MESH_ID]);
-		change = true;
+		if (netif_running(dev))
+			return -EBUSY;
+
+		wdev_lock(wdev);
+		BUILD_BUG_ON(IEEE80211_MAX_SSID_LEN !=
+			     IEEE80211_MAX_MESH_ID_LEN);
+		wdev->mesh_id_up_len =
+			nla_len(info->attrs[NL80211_ATTR_MESH_ID]);
+		memcpy(wdev->ssid, nla_data(info->attrs[NL80211_ATTR_MESH_ID]),
+		       wdev->mesh_id_up_len);
+		wdev_unlock(wdev);
 	}
 
 	if (info->attrs[NL80211_ATTR_4ADDR]) {
@@ -1388,12 +1399,6 @@ static int nl80211_new_interface(struct sk_buff *skb, struct genl_info *info)
 	    !(rdev->wiphy.interface_modes & (1 << type)))
 		return -EOPNOTSUPP;
 
-	if (type == NL80211_IFTYPE_MESH_POINT &&
-	    info->attrs[NL80211_ATTR_MESH_ID]) {
-		params.mesh_id = nla_data(info->attrs[NL80211_ATTR_MESH_ID]);
-		params.mesh_id_len = nla_len(info->attrs[NL80211_ATTR_MESH_ID]);
-	}
-
 	if (info->attrs[NL80211_ATTR_4ADDR]) {
 		params.use_4addr = !!nla_get_u8(info->attrs[NL80211_ATTR_4ADDR]);
 		err = nl80211_valid_4addr(rdev, NULL, params.use_4addr, type);
@@ -1410,6 +1415,20 @@ static int nl80211_new_interface(struct sk_buff *skb, struct genl_info *info)
 	if (IS_ERR(dev))
 		return PTR_ERR(dev);
 
+	if (type == NL80211_IFTYPE_MESH_POINT &&
+	    info->attrs[NL80211_ATTR_MESH_ID]) {
+		struct wireless_dev *wdev = dev->ieee80211_ptr;
+
+		wdev_lock(wdev);
+		BUILD_BUG_ON(IEEE80211_MAX_SSID_LEN !=
+			     IEEE80211_MAX_MESH_ID_LEN);
+		wdev->mesh_id_up_len =
+			nla_len(info->attrs[NL80211_ATTR_MESH_ID]);
+		memcpy(wdev->ssid, nla_data(info->attrs[NL80211_ATTR_MESH_ID]),
+		       wdev->mesh_id_up_len);
+		wdev_unlock(wdev);
+	}
+
 	return 0;
 }
 
@@ -2546,18 +2565,29 @@ static int nl80211_get_mesh_params(struct sk_buff *skb,
 				   struct genl_info *info)
 {
 	struct cfg80211_registered_device *rdev = info->user_ptr[0];
-	struct mesh_config cur_params;
-	int err;
 	struct net_device *dev = info->user_ptr[1];
+	struct wireless_dev *wdev = dev->ieee80211_ptr;
+	struct mesh_config cur_params;
+	int err = 0;
 	void *hdr;
 	struct nlattr *pinfoattr;
 	struct sk_buff *msg;
 
+	if (wdev->iftype != NL80211_IFTYPE_MESH_POINT)
+		return -EOPNOTSUPP;
+
 	if (!rdev->ops->get_mesh_params)
 		return -EOPNOTSUPP;
 
-	/* Get the mesh params */
-	err = rdev->ops->get_mesh_params(&rdev->wiphy, dev, &cur_params);
+	wdev_lock(wdev);
+	/* If not connected, get default parameters */
+	if (!wdev->mesh_id_len)
+		memcpy(&cur_params, &default_mesh_config, sizeof(cur_params));
+	else
+		err = rdev->ops->get_mesh_params(&rdev->wiphy, dev,
+						 &cur_params);
+	wdev_unlock(wdev);
+
 	if (err)
 		return err;
 
@@ -2705,23 +2735,37 @@ do {\
 #undef FILL_IN_MESH_PARAM_IF_SET
 }
 
-static int nl80211_set_mesh_params(struct sk_buff *skb, struct genl_info *info)
+static int nl80211_update_mesh_params(struct sk_buff *skb,
+				      struct genl_info *info)
 {
 	struct cfg80211_registered_device *rdev = info->user_ptr[0];
 	struct net_device *dev = info->user_ptr[1];
+	struct wireless_dev *wdev = dev->ieee80211_ptr;
 	struct mesh_config cfg;
 	u32 mask;
 	int err;
 
-	if (!rdev->ops->set_mesh_params)
+	if (wdev->iftype != NL80211_IFTYPE_MESH_POINT)
+		return -EOPNOTSUPP;
+
+	if (!rdev->ops->update_mesh_params)
 		return -EOPNOTSUPP;
 
 	err = nl80211_parse_mesh_params(info, &cfg, &mask);
 	if (err)
 		return err;
 
-	/* Apply changes */
-	return rdev->ops->set_mesh_params(&rdev->wiphy, dev, &cfg, mask);
+	wdev_lock(wdev);
+	if (!wdev->mesh_id_len)
+		err = -ENOLINK;
+
+	if (!err)
+		err = rdev->ops->update_mesh_params(&rdev->wiphy, dev,
+						    mask, &cfg);
+
+	wdev_unlock(wdev);
+
+	return err;
 }
 
 static int nl80211_get_reg(struct sk_buff *skb, struct genl_info *info)
@@ -4505,6 +4549,41 @@ static int nl80211_set_cqm(struct sk_buff *skb, struct genl_info *info)
 	return err;
 }
 
+static int nl80211_join_mesh(struct sk_buff *skb, struct genl_info *info)
+{
+	struct cfg80211_registered_device *rdev = info->user_ptr[0];
+	struct net_device *dev = info->user_ptr[1];
+	struct mesh_config cfg;
+	int err;
+
+	/* start with default */
+	memcpy(&cfg, &default_mesh_config, sizeof(cfg));
+
+	if (info->attrs[NL80211_ATTR_MESH_PARAMS]) {
+		/* and parse parameters if given */
+		err = nl80211_parse_mesh_params(info, &cfg, NULL);
+		if (err)
+			return err;
+	}
+
+	if (!info->attrs[NL80211_ATTR_MESH_ID] ||
+	    !nla_len(info->attrs[NL80211_ATTR_MESH_ID]))
+		return -EINVAL;
+
+	return cfg80211_join_mesh(rdev, dev,
+				  nla_data(info->attrs[NL80211_ATTR_MESH_ID]),
+				  nla_len(info->attrs[NL80211_ATTR_MESH_ID]),
+				  &cfg);
+}
+
+static int nl80211_leave_mesh(struct sk_buff *skb, struct genl_info *info)
+{
+	struct cfg80211_registered_device *rdev = info->user_ptr[0];
+	struct net_device *dev = info->user_ptr[1];
+
+	return cfg80211_leave_mesh(rdev, dev);
+}
+
 #define NL80211_FLAG_NEED_WIPHY		0x01
 #define NL80211_FLAG_NEED_NETDEV	0x02
 #define NL80211_FLAG_NEED_RTNL		0x04
@@ -4769,10 +4848,10 @@ static struct genl_ops nl80211_ops[] = {
 	},
 	{
 		.cmd = NL80211_CMD_SET_MESH_PARAMS,
-		.doit = nl80211_set_mesh_params,
+		.doit = nl80211_update_mesh_params,
 		.policy = nl80211_policy,
 		.flags = GENL_ADMIN_PERM,
-		.internal_flags = NL80211_FLAG_NEED_NETDEV |
+		.internal_flags = NL80211_FLAG_NEED_NETDEV_UP |
 				  NL80211_FLAG_NEED_RTNL,
 	},
 	{
@@ -4987,6 +5066,22 @@ static struct genl_ops nl80211_ops[] = {
 		.internal_flags = NL80211_FLAG_NEED_NETDEV |
 				  NL80211_FLAG_NEED_RTNL,
 	},
+	{
+		.cmd = NL80211_CMD_JOIN_MESH,
+		.doit = nl80211_join_mesh,
+		.policy = nl80211_policy,
+		.flags = GENL_ADMIN_PERM,
+		.internal_flags = NL80211_FLAG_NEED_NETDEV_UP |
+				  NL80211_FLAG_NEED_RTNL,
+	},
+	{
+		.cmd = NL80211_CMD_LEAVE_MESH,
+		.doit = nl80211_leave_mesh,
+		.policy = nl80211_policy,
+		.flags = GENL_ADMIN_PERM,
+		.internal_flags = NL80211_FLAG_NEED_NETDEV_UP |
+				  NL80211_FLAG_NEED_RTNL,
+	},
 };
 
 static struct genl_multicast_group nl80211_mlme_mcgrp = {

net/wireless/util.c

@@ -792,6 +792,7 @@ int cfg80211_change_iface(struct cfg80211_registered_device *rdev,
 
 	if (ntype != otype) {
 		dev->ieee80211_ptr->use_4addr = false;
+		dev->ieee80211_ptr->mesh_id_up_len = 0;
 
 		switch (otype) {
 		case NL80211_IFTYPE_ADHOC: