wifi: mac80211: rework ack_frame_id handling a bit

Take one more free bit to indicate it's IDR vs. internal
usage, to be able to carve out some bits here for other
internal usage, other than IDR handling with a full ACK
SKB, that is.

Reviewed-by: Benjamin Berg <benjamin.berg@intel.com>
Reviewed-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

5 files changed, 25 insertions, 10 deletions

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 7c707358d15c..7f3b6f00f8a2 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1115,7 +1115,9 @@ ieee80211_rate_get_vht_nss(const struct ieee80211_tx_rate *rate)
  *	not valid if the interface is an MLD since we won't know which
  *	link the frame will be transmitted on
  * @hw_queue: HW queue to put the frame on, skb_get_queue_mapping() gives the AC
- * @ack_frame_id: internal frame ID for TX status, used internally
+ * @status_data: internal data for TX status handling, assigned privately,
+ *	see also &enum ieee80211_status_data for the internal documentation
+ * @status_data_idr: indicates status data is IDR allocated ID for ack frame
  * @tx_time_est: TX time estimate in units of 4us, used internally
  * @control: union part for control data
  * @control.rates: TX rates array to try
@@ -1155,10 +1157,11 @@ struct ieee80211_tx_info {
 	/* common information */
 	u32 flags;
 	u32 band:3,
-	    ack_frame_id:13,
+	    status_data_idr:1,
+	    status_data:13,
 	    hw_queue:4,
 	    tx_time_est:10;
-	/* 2 free bits */
+	/* 1 free bit */
 
 	union {
 		struct {
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 45e7a5d9c7d9..29a6da5ee77f 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -4034,7 +4034,8 @@ int ieee80211_attach_ack_skb(struct ieee80211_local *local, struct sk_buff *skb,
 		return -ENOMEM;
 	}
 
-	IEEE80211_SKB_CB(skb)->ack_frame_id = id;
+	IEEE80211_SKB_CB(skb)->status_data_idr = 1;
+	IEEE80211_SKB_CB(skb)->status_data = id;
 
 	*cookie = ieee80211_mgmt_tx_cookie(local);
 	IEEE80211_SKB_CB(ack_skb)->ack.cookie = *cookie;
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 06bd406846d2..7b74cf96ee0a 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -85,6 +85,11 @@ extern const u8 ieee80211_ac_to_qos_mask[IEEE80211_NUM_ACS];
 
 #define IEEE80211_MAX_NAN_INSTANCE_ID 255
 
+enum ieee80211_status_data {
+	IEEE80211_STATUS_TYPE_MASK	= 0x00f,
+	IEEE80211_STATUS_TYPE_INVALID	= 0,
+	IEEE80211_STATUS_SUBDATA_MASK	= 0xff0,
+};
 
 /*
  * Keep a station's queues on the active list for deficit accounting purposes
diff --git a/net/mac80211/status.c b/net/mac80211/status.c
index 44d83da60aee..f24aceb59db0 100644
--- a/net/mac80211/status.c
+++ b/net/mac80211/status.c
@@ -633,7 +633,7 @@ static void ieee80211_report_ack_skb(struct ieee80211_local *local,
 	unsigned long flags;
 
 	spin_lock_irqsave(&local->ack_status_lock, flags);
-	skb = idr_remove(&local->ack_status_frames, info->ack_frame_id);
+	skb = idr_remove(&local->ack_status_frames, info->status_data);
 	spin_unlock_irqrestore(&local->ack_status_lock, flags);
 
 	if (!skb)
@@ -759,7 +759,7 @@ static void ieee80211_report_used_skb(struct ieee80211_local *local,
 		}
 
 		rcu_read_unlock();
-	} else if (info->ack_frame_id) {
+	} else if (info->status_data_idr) {
 		ieee80211_report_ack_skb(local, skb, acked, dropped,
 					 ack_hwtstamp);
 	}
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 3a5b41c2ee3d..ae33f727c6a8 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -2942,7 +2942,10 @@ static struct sk_buff *ieee80211_build_hdr(struct ieee80211_sub_if_data *sdata,
 	memset(info, 0, sizeof(*info));
 
 	info->flags = info_flags;
-	info->ack_frame_id = info_id;
+	if (info_id) {
+		info->status_data = info_id;
+		info->status_data_idr = 1;
+	}
 	info->band = band;
 
 	if (likely(!cookie)) {
@@ -4639,9 +4642,12 @@ static void ieee80211_8023_xmit(struct ieee80211_sub_if_data *sdata,
 	}
 
 	if (unlikely(skb->sk &&
-		     skb_shinfo(skb)->tx_flags & SKBTX_WIFI_STATUS))
-		info->ack_frame_id = ieee80211_store_ack_skb(local, skb,
-							     &info->flags, NULL);
+		     skb_shinfo(skb)->tx_flags & SKBTX_WIFI_STATUS)) {
+		info->status_data = ieee80211_store_ack_skb(local, skb,
+							    &info->flags, NULL);
+		if (info->status_data)
+			info->status_data_idr = 1;
+	}
 
 	dev_sw_netstats_tx_add(dev, skbs, len);
 	sta->deflink.tx_stats.packets[queue] += skbs;