cfg80211/mac80211: disconnect on suspend

If possible that after suspend, cfg80211 will receive request to
disconnect what require action on interface that was removed during
suspend.

Problem can manifest itself by various warnings similar to below one:

WARNING: at net/mac80211/driver-ops.h:12 ieee80211_bss_info_change_notify+0x2f9/0x300 [mac80211]()
wlan0:  Failed check-sdata-in-driver check, flags: 0x4
Call Trace:
 [<c043e0b3>] warn_slowpath_fmt+0x33/0x40
 [<f83707c9>] ieee80211_bss_info_change_notify+0x2f9/0x300 [mac80211]
 [<f83a660a>] ieee80211_recalc_ps_vif+0x2a/0x30 [mac80211]
 [<f83a6706>] ieee80211_set_disassoc+0xf6/0x500 [mac80211]
 [<f83a9441>] ieee80211_mgd_deauth+0x1f1/0x280 [mac80211]
 [<f8381b36>] ieee80211_deauth+0x16/0x20 [mac80211]
 [<f8261e70>] cfg80211_mlme_down+0x70/0xc0 [cfg80211]
 [<f8264de1>] __cfg80211_disconnect+0x1b1/0x1d0 [cfg80211]

To fix the problem disconnect from any associated network before
suspend. User space is responsible to establish connection again
after resume. This basically need to be done by user space anyway,
because associated stations can go away during suspend (for example
NetworkManager disconnects on suspend and connect on resume by default).

Patch also handle situation when driver refuse to suspend with wowlan
configured and try to suspend again without it.

CRs-Fixed: 1114636
Change-Id: I6f2265a65dd47e3b127ba6236e4c9cf7ba77fc09
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next.git
Git-commit: 8125696991194aacb1173b6e8196d19098b44e17
[rsirasan@codeaurora.org: Resolved merge conflicts]
Signed-off-by: Rajeev Kumar Sirasanagandla <rsirasan@codeaurora.org>

1 files changed, 58 insertions, 34 deletions

diff --git a/net/wireless/core.c b/net/wireless/core.c
index 14868e42f3ca..30e1a6c027bb 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -927,6 +927,63 @@ void cfg80211_update_iface_num(struct cfg80211_registered_device *rdev,
 		rdev->num_running_monitor_ifaces += num;
 }
 
+void cfg80211_leave(struct cfg80211_registered_device *rdev,
+		    struct wireless_dev *wdev)
+{
+	struct net_device *dev = wdev->netdev;
+	struct cfg80211_sched_scan_request *sched_scan_req;
+
+	ASSERT_RTNL();
+
+	switch (wdev->iftype) {
+	case NL80211_IFTYPE_ADHOC:
+		cfg80211_leave_ibss(rdev, dev, true);
+		break;
+	case NL80211_IFTYPE_P2P_CLIENT:
+	case NL80211_IFTYPE_STATION:
+		sched_scan_req = rtnl_dereference(rdev->sched_scan_req);
+		if (sched_scan_req && dev == sched_scan_req->dev)
+			__cfg80211_stop_sched_scan(rdev, false);
+		wdev_lock(wdev);
+#ifdef CONFIG_CFG80211_WEXT
+		kfree(wdev->wext.ie);
+		wdev->wext.ie = NULL;
+		wdev->wext.ie_len = 0;
+		wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
+#endif
+		cfg80211_disconnect(rdev, dev,
+				    WLAN_REASON_DEAUTH_LEAVING, true);
+		cfg80211_mlme_down(rdev, dev);
+		wdev_unlock(wdev);
+		break;
+	case NL80211_IFTYPE_MESH_POINT:
+		cfg80211_leave_mesh(rdev, dev);
+		break;
+	case NL80211_IFTYPE_AP:
+	case NL80211_IFTYPE_P2P_GO:
+		cfg80211_stop_ap(rdev, dev, false);
+		break;
+	case NL80211_IFTYPE_OCB:
+		__cfg80211_leave_ocb(rdev, dev);
+		break;
+	case NL80211_IFTYPE_WDS:
+		/* must be handled by mac80211/driver, has no APIs */
+		break;
+	case NL80211_IFTYPE_P2P_DEVICE:
+		/* cannot happen, has no netdev */
+		break;
+	case NL80211_IFTYPE_AP_VLAN:
+	case NL80211_IFTYPE_MONITOR:
+		/* nothing to do */
+		break;
+	case NL80211_IFTYPE_UNSPECIFIED:
+	case NUM_NL80211_IFTYPES:
+		/* invalid */
+		break;
+	}
+	wdev->beacon_interval = 0;
+}
+
 static int cfg80211_netdev_notifier_call(struct notifier_block *nb,
 					 unsigned long state, void *ptr)
 {
@@ -988,40 +1045,7 @@ static int cfg80211_netdev_notifier_call(struct notifier_block *nb,
 			dev->priv_flags |= IFF_DONT_BRIDGE;
 		break;
 	case NETDEV_GOING_DOWN:
-		switch (wdev->iftype) {
-		case NL80211_IFTYPE_ADHOC:
-			cfg80211_leave_ibss(rdev, dev, true);
-			break;
-		case NL80211_IFTYPE_P2P_CLIENT:
-		case NL80211_IFTYPE_STATION:
-			ASSERT_RTNL();
-			sched_scan_req = rtnl_dereference(rdev->sched_scan_req);
-			if (sched_scan_req && dev == sched_scan_req->dev)
-				__cfg80211_stop_sched_scan(rdev, false);
-
-			wdev_lock(wdev);
-#ifdef CONFIG_CFG80211_WEXT
-			kfree(wdev->wext.ie);
-			wdev->wext.ie = NULL;
-			wdev->wext.ie_len = 0;
-			wdev->wext.connect.auth_type =
-						NL80211_AUTHTYPE_AUTOMATIC;
-#endif
-			cfg80211_disconnect(rdev, dev,
-					WLAN_REASON_DEAUTH_LEAVING, true);
-			cfg80211_mlme_down(rdev, dev);
-			wdev_unlock(wdev);
-			break;
-		case NL80211_IFTYPE_MESH_POINT:
-			cfg80211_leave_mesh(rdev, dev);
-			break;
-		case NL80211_IFTYPE_AP:
-			cfg80211_stop_ap(rdev, dev, false);
-			break;
-		default:
-			break;
-		}
-		wdev->beacon_interval = 0;
+		cfg80211_leave(rdev, wdev);
 		break;
 	case NETDEV_DOWN:
 		cfg80211_update_iface_num(rdev, wdev->iftype, -1);