mac80211: make client powersave independent of interface type

This patch prepares mac80211 for a later implementation of mesh or
ad-hoc powersave clients.
The structures related to powersave (buffer, TIM map, counters) are
moved from the AP-specific interface structure to a generic structure
that can be embedded into any interface type.
The functions related to powersave are prepared to allow easy
extension with different interface types. For example with:

+ } else if (sta->sdata->vif.type == NL80211_IFTYPE_MESH_POINT) {
+         ps = &sdata->u.mesh.ps;

Some references to the AP's beacon structure are removed where they
were obviously not used.

The patch compiles without warning and has been briefly tested as AP
interface with one client in PS mode.

Signed-off-by: Marco Porsch <marco.porsch@etit.tu-chemnitz.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 58 insertions, 42 deletions

diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index bbe1d86beea1..065f81cb5618 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -325,16 +325,19 @@ static void purge_old_ps_buffers(struct ieee80211_local *local)
 	struct sta_info *sta;
 
 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
-		struct ieee80211_if_ap *ap;
-		if (sdata->vif.type != NL80211_IFTYPE_AP)
+		struct ps_data *ps;
+
+		if (sdata->vif.type == NL80211_IFTYPE_AP)
+			ps = &sdata->u.ap.ps;
+		else
 			continue;
-		ap = &sdata->u.ap;
-		skb = skb_dequeue(&ap->ps_bc_buf);
+
+		skb = skb_dequeue(&ps->bc_buf);
 		if (skb) {
 			purged++;
 			dev_kfree_skb(skb);
 		}
-		total += skb_queue_len(&ap->ps_bc_buf);
+		total += skb_queue_len(&ps->bc_buf);
 	}
 
 	/*
@@ -364,6 +367,7 @@ ieee80211_tx_h_multicast_ps_buf(struct ieee80211_tx_data *tx)
 {
 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
+	struct ps_data *ps;
 
 	/*
 	 * broadcast/multicast frame
@@ -373,16 +377,24 @@ ieee80211_tx_h_multicast_ps_buf(struct ieee80211_tx_data *tx)
 	 * This is done either by the hardware or us.
 	 */
 
-	/* powersaving STAs only in AP/VLAN mode */
-	if (!tx->sdata->bss)
+	/* powersaving STAs currently only in AP/VLAN mode */
+	if (tx->sdata->vif.type == NL80211_IFTYPE_AP ||
+	    tx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
+		if (!tx->sdata->bss)
+			return TX_CONTINUE;
+
+		ps = &tx->sdata->bss->ps;
+	} else {
 		return TX_CONTINUE;
+	}
+
 
 	/* no buffering for ordered frames */
 	if (ieee80211_has_order(hdr->frame_control))
 		return TX_CONTINUE;
 
 	/* no stations in PS mode */
-	if (!atomic_read(&tx->sdata->bss->num_sta_ps))
+	if (!atomic_read(&ps->num_sta_ps))
 		return TX_CONTINUE;
 
 	info->flags |= IEEE80211_TX_CTL_SEND_AFTER_DTIM;
@@ -397,14 +409,14 @@ ieee80211_tx_h_multicast_ps_buf(struct ieee80211_tx_data *tx)
 	if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
 		purge_old_ps_buffers(tx->local);
 
-	if (skb_queue_len(&tx->sdata->bss->ps_bc_buf) >= AP_MAX_BC_BUFFER) {
+	if (skb_queue_len(&ps->bc_buf) >= AP_MAX_BC_BUFFER) {
 		ps_dbg(tx->sdata,
 		       "BC TX buffer full - dropping the oldest frame\n");
-		dev_kfree_skb(skb_dequeue(&tx->sdata->bss->ps_bc_buf));
+		dev_kfree_skb(skb_dequeue(&ps->bc_buf));
 	} else
 		tx->local->total_ps_buffered++;
 
-	skb_queue_tail(&tx->sdata->bss->ps_bc_buf, tx->skb);
+	skb_queue_tail(&ps->bc_buf, tx->skb);
 
 	return TX_QUEUED;
 }
@@ -2246,9 +2258,8 @@ void ieee80211_tx_pending(unsigned long data)
 /* functions for drivers to get certain frames */
 
 static void ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
-				     struct ieee80211_if_ap *bss,
-				     struct sk_buff *skb,
-				     struct beacon_data *beacon)
+				     struct ps_data *ps,
+				     struct sk_buff *skb)
 {
 	u8 *pos, *tim;
 	int aid0 = 0;
@@ -2256,27 +2267,27 @@ static void ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
 
 	/* Generate bitmap for TIM only if there are any STAs in power save
 	 * mode. */
-	if (atomic_read(&bss->num_sta_ps) > 0)
+	if (atomic_read(&ps->num_sta_ps) > 0)
 		/* in the hope that this is faster than
 		 * checking byte-for-byte */
-		have_bits = !bitmap_empty((unsigned long*)bss->tim,
+		have_bits = !bitmap_empty((unsigned long*)ps->tim,
 					  IEEE80211_MAX_AID+1);
 
-	if (bss->dtim_count == 0)
-		bss->dtim_count = sdata->vif.bss_conf.dtim_period - 1;
+	if (ps->dtim_count == 0)
+		ps->dtim_count = sdata->vif.bss_conf.dtim_period - 1;
 	else
-		bss->dtim_count--;
+		ps->dtim_count--;
 
 	tim = pos = (u8 *) skb_put(skb, 6);
 	*pos++ = WLAN_EID_TIM;
 	*pos++ = 4;
-	*pos++ = bss->dtim_count;
+	*pos++ = ps->dtim_count;
 	*pos++ = sdata->vif.bss_conf.dtim_period;
 
-	if (bss->dtim_count == 0 && !skb_queue_empty(&bss->ps_bc_buf))
+	if (ps->dtim_count == 0 && !skb_queue_empty(&ps->bc_buf))
 		aid0 = 1;
 
-	bss->dtim_bc_mc = aid0 == 1;
+	ps->dtim_bc_mc = aid0 == 1;
 
 	if (have_bits) {
 		/* Find largest even number N1 so that bits numbered 1 through
@@ -2284,14 +2295,14 @@ static void ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
 		 * (N2 + 1) x 8 through 2007 are 0. */
 		n1 = 0;
 		for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) {
-			if (bss->tim[i]) {
+			if (ps->tim[i]) {
 				n1 = i & 0xfe;
 				break;
 			}
 		}
 		n2 = n1;
 		for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) {
-			if (bss->tim[i]) {
+			if (ps->tim[i]) {
 				n2 = i;
 				break;
 			}
@@ -2301,7 +2312,7 @@ static void ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
 		*pos++ = n1 | aid0;
 		/* Part Virt Bitmap */
 		skb_put(skb, n2 - n1);
-		memcpy(pos, bss->tim + n1, n2 - n1 + 1);
+		memcpy(pos, ps->tim + n1, n2 - n1 + 1);
 
 		tim[1] = n2 - n1 + 4;
 	} else {
@@ -2318,8 +2329,6 @@ struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
 	struct sk_buff *skb = NULL;
 	struct ieee80211_tx_info *info;
 	struct ieee80211_sub_if_data *sdata = NULL;
-	struct ieee80211_if_ap *ap = NULL;
-	struct beacon_data *beacon;
 	enum ieee80211_band band;
 	struct ieee80211_tx_rate_control txrc;
 	struct ieee80211_chanctx_conf *chanctx_conf;
@@ -2338,8 +2347,9 @@ struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
 		*tim_length = 0;
 
 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
-		ap = &sdata->u.ap;
-		beacon = rcu_dereference(ap->beacon);
+		struct ieee80211_if_ap *ap = &sdata->u.ap;
+		struct beacon_data *beacon = rcu_dereference(ap->beacon);
+
 		if (beacon) {
 			/*
 			 * headroom, head length,
@@ -2363,14 +2373,12 @@ struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
 			 * of the tim bitmap in mac80211 and the driver.
 			 */
 			if (local->tim_in_locked_section) {
-				ieee80211_beacon_add_tim(sdata, ap, skb,
-							 beacon);
+				ieee80211_beacon_add_tim(sdata, &ap->ps, skb);
 			} else {
 				unsigned long flags;
 
 				spin_lock_irqsave(&local->tim_lock, flags);
-				ieee80211_beacon_add_tim(sdata, ap, skb,
-							 beacon);
+				ieee80211_beacon_add_tim(sdata, &ap->ps, skb);
 				spin_unlock_irqrestore(&local->tim_lock, flags);
 			}
 
@@ -2694,32 +2702,40 @@ ieee80211_get_buffered_bc(struct ieee80211_hw *hw,
 	struct sk_buff *skb = NULL;
 	struct ieee80211_tx_data tx;
 	struct ieee80211_sub_if_data *sdata;
-	struct ieee80211_if_ap *bss = NULL;
-	struct beacon_data *beacon;
+	struct ps_data *ps;
 	struct ieee80211_tx_info *info;
 	struct ieee80211_chanctx_conf *chanctx_conf;
 
 	sdata = vif_to_sdata(vif);
-	bss = &sdata->u.ap;
 
 	rcu_read_lock();
-	beacon = rcu_dereference(bss->beacon);
 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 
-	if (sdata->vif.type != NL80211_IFTYPE_AP || !beacon || !beacon->head ||
-	    !chanctx_conf)
+	if (!chanctx_conf)
+		goto out;
+
+	if (sdata->vif.type == NL80211_IFTYPE_AP) {
+		struct beacon_data *beacon =
+				rcu_dereference(sdata->u.ap.beacon);
+
+		if (!beacon || !beacon->head)
+			goto out;
+
+		ps = &sdata->u.ap.ps;
+	} else {
 		goto out;
+	}
 
-	if (bss->dtim_count != 0 || !bss->dtim_bc_mc)
+	if (ps->dtim_count != 0 || !ps->dtim_bc_mc)
 		goto out; /* send buffered bc/mc only after DTIM beacon */
 
 	while (1) {
-		skb = skb_dequeue(&bss->ps_bc_buf);
+		skb = skb_dequeue(&ps->bc_buf);
 		if (!skb)
 			goto out;
 		local->total_ps_buffered--;
 
-		if (!skb_queue_empty(&bss->ps_bc_buf) && skb->len >= 2) {
+		if (!skb_queue_empty(&ps->bc_buf) && skb->len >= 2) {
 			struct ieee80211_hdr *hdr =
 				(struct ieee80211_hdr *) skb->data;
 			/* more buffered multicast/broadcast frames ==> set