mac80211: make master netdev handling sane

Currently, almost every interface type has a 'bss' pointer
pointing to BSS information. This BSS information, however,
is for a _local_ BSS, not for the BSS we joined, so having
it on a STA mode interface makes little sense, but now they
have it pointing to the master device, which is an AP mode
virtual interface. However, except for some bitrate control
data, this pointer is only used in AP/VLAN modes (for power
saving stations.)

Overall, it is not necessary to even have the master netdev
be a valid virtual interface, and it doesn't have to be on
the list of interfaces either.

This patch changes the master netdev to be special, it now
 - no longer is on the list of virtual interfaces, which
   lets me remove a lot of tests for that
 - no longer has sub_if_data attached, since that isn't used

Additionally, this patch changes some vlan/ap mode handling
that is related to these 'bss' pointers described above (but
in the VLAN case they actually make sense because there they
point to the AP they belong to); it also adds some debugging
code to IEEE80211_DEV_TO_SUB_IF to validate it is not called
on the master netdev any more.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 24 insertions, 17 deletions

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 02a8753..1b1fc53 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -237,8 +237,6 @@ struct ieee80211_if_ap {
 	struct sk_buff_head ps_bc_buf;
 	atomic_t num_sta_ps; /* number of stations in PS mode */
 	int dtim_count;
-	int force_unicast_rateidx; /* forced TX rateidx for unicast frames */
-	int max_ratectrl_rateidx; /* max TX rateidx for rate control */
 	int num_beacons; /* number of TXed beacon frames for this BSS */
 };
 
@@ -248,7 +246,6 @@ struct ieee80211_if_wds {
 };
 
 struct ieee80211_if_vlan {
-	struct ieee80211_sub_if_data *ap;
 	struct list_head list;
 };
 
@@ -432,16 +429,18 @@ struct ieee80211_sub_if_data {
 	struct ieee80211_key *keys[NUM_DEFAULT_KEYS];
 	struct ieee80211_key *default_key;
 
+	/* BSS configuration for this interface. */
+	struct ieee80211_bss_conf bss_conf;
+
 	/*
-	 * BSS configuration for this interface.
-	 *
-	 * FIXME: I feel bad putting this here when we already have a
-	 *	  bss pointer, but the bss pointer is just wrong when
-	 *	  you have multiple virtual STA mode interfaces...
-	 *	  This needs to be fixed.
+	 * AP this belongs to: self in AP mode and
+	 * corresponding AP in VLAN mode, NULL for
+	 * all others (might be needed later in IBSS)
 	 */
-	struct ieee80211_bss_conf bss_conf;
-	struct ieee80211_if_ap *bss; /* BSS that this device belongs to */
+	struct ieee80211_if_ap *bss;
+
+	int force_unicast_rateidx; /* forced TX rateidx for unicast frames */
+	int max_ratectrl_rateidx; /* max TX rateidx for rate control */
 
 	union {
 		struct ieee80211_if_ap ap;
@@ -533,8 +532,6 @@ struct ieee80211_sub_if_data *vif_to_sdata(struct ieee80211_vif *p)
 	return container_of(p, struct ieee80211_sub_if_data, vif);
 }
 
-#define IEEE80211_DEV_TO_SUB_IF(dev) netdev_priv(dev)
-
 enum {
 	IEEE80211_RX_MSG	= 1,
 	IEEE80211_TX_STATUS_MSG	= 2,
@@ -760,6 +757,16 @@ static inline int ieee80211_is_multiqueue(struct ieee80211_local *local)
 #endif
 }
 
+static inline struct ieee80211_sub_if_data *
+IEEE80211_DEV_TO_SUB_IF(struct net_device *dev)
+{
+	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
+
+	BUG_ON(!local || local->mdev == dev);
+
+	return netdev_priv(dev);
+}
+
 /* this struct represents 802.11n's RA/TID combination */
 struct ieee80211_ra_tid {
 	u8 ra[ETH_ALEN];
@@ -883,8 +890,8 @@ int ieee80211_sta_scan_results(struct net_device *dev,
 ieee80211_rx_result ieee80211_sta_rx_scan(
 	struct net_device *dev, struct sk_buff *skb,
 	struct ieee80211_rx_status *rx_status);
-void ieee80211_rx_bss_list_init(struct net_device *dev);
-void ieee80211_rx_bss_list_deinit(struct net_device *dev);
+void ieee80211_rx_bss_list_init(struct ieee80211_local *local);
+void ieee80211_rx_bss_list_deinit(struct ieee80211_local *local);
 int ieee80211_sta_set_extra_ie(struct net_device *dev, char *ie, size_t len);
 struct sta_info *ieee80211_ibss_add_sta(struct net_device *dev,
 					struct sk_buff *skb, u8 *bssid,
@@ -925,8 +932,8 @@ static inline void ieee80211_start_mesh(struct net_device *dev)
 {}
 #endif
 
-/* ieee80211_iface.c */
-int ieee80211_if_add(struct net_device *dev, const char *name,
+/* interface handling */
+int ieee80211_if_add(struct ieee80211_local *local, const char *name,
 		     struct net_device **new_dev, int type,
 		     struct vif_params *params);
 void ieee80211_if_set_type(struct net_device *dev, int type);