mac80211: don't store napi struct

When introducing multiple RX queues, a single NAPI struct will not
be sufficient. Instead of trying to store multiple, simply change
the API to have the NAPI struct passed to the RX function. This of
course means that drivers using rx_irqsafe() cannot use NAPI, but
that seems a reasonable trade-off, particularly since only two of
all drivers are currently using it at all.

While at it, we can now remove the IEEE80211_RX_REORDER_TIMER flag
again since this code path cannot have a napi struct anyway.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

3 files changed, 11 insertions, 25 deletions

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 361bb3c..7d75f93 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -202,8 +202,6 @@ enum ieee80211_packet_rx_flags {
  * @IEEE80211_RX_CMNTR: received on cooked monitor already
  * @IEEE80211_RX_BEACON_REPORTED: This frame was already reported
  *	to cfg80211_report_obss_beacon().
- * @IEEE80211_RX_REORDER_TIMER: this frame is released by the
- *	reorder buffer timeout timer, not the normal RX path
  *
  * These flags are used across handling multiple interfaces
  * for a single frame.
@@ -211,10 +209,10 @@ enum ieee80211_packet_rx_flags {
 enum ieee80211_rx_flags {
 	IEEE80211_RX_CMNTR		= BIT(0),
 	IEEE80211_RX_BEACON_REPORTED	= BIT(1),
-	IEEE80211_RX_REORDER_TIMER	= BIT(2),
 };
 
 struct ieee80211_rx_data {
+	struct napi_struct *napi;
 	struct sk_buff *skb;
 	struct ieee80211_local *local;
 	struct ieee80211_sub_if_data *sdata;
@@ -1347,8 +1345,6 @@ struct ieee80211_local {
 
 	struct ieee80211_sub_if_data __rcu *p2p_sdata;
 
-	struct napi_struct *napi;
-
 	/* virtual monitor interface */
 	struct ieee80211_sub_if_data __rcu *monitor_sdata;
 	struct cfg80211_chan_def monitor_chandef;
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index 3c63468..dba0a86 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -1132,18 +1132,6 @@ int ieee80211_register_hw(struct ieee80211_hw *hw)
 }
 EXPORT_SYMBOL(ieee80211_register_hw);
 
-void ieee80211_napi_add(struct ieee80211_hw *hw, struct napi_struct *napi,
-			struct net_device *napi_dev,
-			int (*poll)(struct napi_struct *, int),
-			int weight)
-{
-	struct ieee80211_local *local = hw_to_local(hw);
-
-	netif_napi_add(napi_dev, napi, poll, weight);
-	local->napi = napi;
-}
-EXPORT_SYMBOL_GPL(ieee80211_napi_add);
-
 void ieee80211_unregister_hw(struct ieee80211_hw *hw)
 {
 	struct ieee80211_local *local = hw_to_local(hw);
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index dd6bb2a..817bf22 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -2148,9 +2148,8 @@ ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
 		/* deliver to local stack */
 		skb->protocol = eth_type_trans(skb, dev);
 		memset(skb->cb, 0, sizeof(skb->cb));
-		if (!(rx->flags & IEEE80211_RX_REORDER_TIMER) &&
-		    rx->local->napi)
-			napi_gro_receive(rx->local->napi, skb);
+		if (rx->napi)
+			napi_gro_receive(rx->napi, skb);
 		else
 			netif_receive_skb(skb);
 	}
@@ -3256,7 +3255,7 @@ void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
 		/* This is OK -- must be QoS data frame */
 		.security_idx = tid,
 		.seqno_idx = tid,
-		.flags = IEEE80211_RX_REORDER_TIMER,
+		.napi = NULL, /* must be NULL to not have races */
 	};
 	struct tid_ampdu_rx *tid_agg_rx;
 
@@ -3433,7 +3432,8 @@ static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
  * be called with rcu_read_lock protection.
  */
 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
-					 struct sk_buff *skb)
+					 struct sk_buff *skb,
+					 struct napi_struct *napi)
 {
 	struct ieee80211_local *local = hw_to_local(hw);
 	struct ieee80211_sub_if_data *sdata;
@@ -3449,6 +3449,7 @@ static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
 	memset(&rx, 0, sizeof(rx));
 	rx.skb = skb;
 	rx.local = local;
+	rx.napi = napi;
 
 	if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
 		I802_DEBUG_INC(local->dot11ReceivedFragmentCount);
@@ -3550,7 +3551,8 @@ static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
  * This is the receive path handler. It is called by a low level driver when an
  * 802.11 MPDU is received from the hardware.
  */
-void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
+void ieee80211_rx_napi(struct ieee80211_hw *hw, struct sk_buff *skb,
+		       struct napi_struct *napi)
 {
 	struct ieee80211_local *local = hw_to_local(hw);
 	struct ieee80211_rate *rate = NULL;
@@ -3649,7 +3651,7 @@ void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
 	ieee80211_tpt_led_trig_rx(local,
 			((struct ieee80211_hdr *)skb->data)->frame_control,
 			skb->len);
-	__ieee80211_rx_handle_packet(hw, skb);
+	__ieee80211_rx_handle_packet(hw, skb, napi);
 
 	rcu_read_unlock();
 
@@ -3657,7 +3659,7 @@ void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
  drop:
 	kfree_skb(skb);
 }
-EXPORT_SYMBOL(ieee80211_rx);
+EXPORT_SYMBOL(ieee80211_rx_napi);
 
 /* This is a version of the rx handler that can be called from hard irq
  * context. Post the skb on the queue and schedule the tasklet */