diff mbox

[v2,2/5] mac80211: move aMPDU RX reorder code

Message ID 20091125164821.018412090@sipsolutions.net (mailing list archive)
State Not Applicable, archived
Headers show

Commit Message

Johannes Berg Nov. 25, 2009, 4:46 p.m. UTC
None
diff mbox

Patch

--- wireless-testing.orig/net/mac80211/rx.c	2009-11-19 01:14:17.000000000 +0100
+++ wireless-testing/net/mac80211/rx.c	2009-11-19 01:14:21.000000000 +0100
@@ -27,9 +27,9 @@ 
 #include "tkip.h"
 #include "wme.h"
 
-static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw,
-					     struct tid_ampdu_rx *tid_agg_rx,
-					     u16 head_seq_num);
+static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
+					 struct sk_buff *skb,
+					 struct ieee80211_rate *rate);
 
 /*
  * monitor mode reception
@@ -534,6 +534,232 @@  ieee80211_rx_mesh_check(struct ieee80211
 	return RX_CONTINUE;
 }
 
+#define SEQ_MODULO 0x1000
+#define SEQ_MASK   0xfff
+
+static inline int seq_less(u16 sq1, u16 sq2)
+{
+	return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
+}
+
+static inline u16 seq_inc(u16 sq)
+{
+	return (sq + 1) & SEQ_MASK;
+}
+
+static inline u16 seq_sub(u16 sq1, u16 sq2)
+{
+	return (sq1 - sq2) & SEQ_MASK;
+}
+
+
+static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
+					    struct tid_ampdu_rx *tid_agg_rx,
+					    int index)
+{
+	struct ieee80211_supported_band *sband;
+	struct ieee80211_rate *rate = NULL;
+	struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
+	struct ieee80211_rx_status *status;
+
+	if (!skb)
+		goto no_frame;
+
+	status = IEEE80211_SKB_RXCB(skb);
+
+	/* release the reordered frames to stack */
+	sband = hw->wiphy->bands[status->band];
+	if (!(status->flag & RX_FLAG_HT))
+		rate = &sband->bitrates[status->rate_idx];
+	__ieee80211_rx_handle_packet(hw, skb, rate);
+	tid_agg_rx->stored_mpdu_num--;
+	tid_agg_rx->reorder_buf[index] = NULL;
+
+no_frame:
+	tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
+}
+
+static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw,
+					     struct tid_ampdu_rx *tid_agg_rx,
+					     u16 head_seq_num)
+{
+	int index;
+
+	while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
+		index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
+							tid_agg_rx->buf_size;
+		ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
+	}
+}
+
+/*
+ * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
+ * the skb was added to the buffer longer than this time ago, the earlier
+ * frames that have not yet been received are assumed to be lost and the skb
+ * can be released for processing. This may also release other skb's from the
+ * reorder buffer if there are no additional gaps between the frames.
+ */
+#define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
+
+/*
+ * As this function belongs to the RX path it must be under
+ * rcu_read_lock protection. It returns false if the frame
+ * can be processed immediately, true if it was consumed.
+ */
+static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
+					     struct tid_ampdu_rx *tid_agg_rx,
+					     struct sk_buff *skb)
+{
+	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
+	u16 sc = le16_to_cpu(hdr->seq_ctrl);
+	u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
+	u16 head_seq_num, buf_size;
+	int index;
+
+	buf_size = tid_agg_rx->buf_size;
+	head_seq_num = tid_agg_rx->head_seq_num;
+
+	/* frame with out of date sequence number */
+	if (seq_less(mpdu_seq_num, head_seq_num)) {
+		dev_kfree_skb(skb);
+		return true;
+	}
+
+	/*
+	 * If frame the sequence number exceeds our buffering window
+	 * size release some previous frames to make room for this one.
+	 */
+	if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) {
+		head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size));
+		/* release stored frames up to new head to stack */
+		ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num);
+	}
+
+	/* Now the new frame is always in the range of the reordering buffer */
+
+	index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size;
+
+	/* check if we already stored this frame */
+	if (tid_agg_rx->reorder_buf[index]) {
+		dev_kfree_skb(skb);
+		return true;
+	}
+
+	/*
+	 * If the current MPDU is in the right order and nothing else
+	 * is stored we can process it directly, no need to buffer it.
+	 */
+	if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
+	    tid_agg_rx->stored_mpdu_num == 0) {
+		tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
+		return false;
+	}
+
+	/* put the frame in the reordering buffer */
+	tid_agg_rx->reorder_buf[index] = skb;
+	tid_agg_rx->reorder_time[index] = jiffies;
+	tid_agg_rx->stored_mpdu_num++;
+	/* release the buffer until next missing frame */
+	index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
+						tid_agg_rx->buf_size;
+	if (!tid_agg_rx->reorder_buf[index] &&
+	    tid_agg_rx->stored_mpdu_num > 1) {
+		/*
+		 * No buffers ready to be released, but check whether any
+		 * frames in the reorder buffer have timed out.
+		 */
+		int j;
+		int skipped = 1;
+		for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
+		     j = (j + 1) % tid_agg_rx->buf_size) {
+			if (!tid_agg_rx->reorder_buf[j]) {
+				skipped++;
+				continue;
+			}
+			if (!time_after(jiffies, tid_agg_rx->reorder_time[j] +
+					HT_RX_REORDER_BUF_TIMEOUT))
+				break;
+
+#ifdef CONFIG_MAC80211_HT_DEBUG
+			if (net_ratelimit())
+				printk(KERN_DEBUG "%s: release an RX reorder "
+				       "frame due to timeout on earlier "
+				       "frames\n",
+				       wiphy_name(hw->wiphy));
+#endif
+			ieee80211_release_reorder_frame(hw, tid_agg_rx, j);
+
+			/*
+			 * Increment the head seq# also for the skipped slots.
+			 */
+			tid_agg_rx->head_seq_num =
+				(tid_agg_rx->head_seq_num + skipped) & SEQ_MASK;
+			skipped = 0;
+		}
+	} else while (tid_agg_rx->reorder_buf[index]) {
+		ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
+		index =	seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
+							tid_agg_rx->buf_size;
+	}
+
+	return true;
+}
+
+/*
+ * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
+ * true if the MPDU was buffered, false if it should be processed.
+ */
+static bool ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
+				       struct sk_buff *skb)
+{
+	struct ieee80211_hw *hw = &local->hw;
+	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
+	struct sta_info *sta;
+	struct tid_ampdu_rx *tid_agg_rx;
+	u16 sc;
+	int tid;
+
+	if (!ieee80211_is_data_qos(hdr->frame_control))
+		return false;
+
+	/*
+	 * filter the QoS data rx stream according to
+	 * STA/TID and check if this STA/TID is on aggregation
+	 */
+
+	sta = sta_info_get(local, hdr->addr2);
+	if (!sta)
+		return false;
+
+	tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
+
+	if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL)
+		return false;
+
+	tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
+
+	/* qos null data frames are excluded */
+	if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
+		return false;
+
+	/* new, potentially un-ordered, ampdu frame - process it */
+
+	/* reset session timer */
+	if (tid_agg_rx->timeout)
+		mod_timer(&tid_agg_rx->session_timer,
+			  TU_TO_EXP_TIME(tid_agg_rx->timeout));
+
+	/* if this mpdu is fragmented - terminate rx aggregation session */
+	sc = le16_to_cpu(hdr->seq_ctrl);
+	if (sc & IEEE80211_SCTL_FRAG) {
+		ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr,
+			tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
+		dev_kfree_skb(skb);
+		return true;
+	}
+
+	return ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb);
+}
 
 static ieee80211_rx_result debug_noinline
 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
@@ -2187,233 +2413,6 @@  static void __ieee80211_rx_handle_packet
 		dev_kfree_skb(skb);
 }
 
-#define SEQ_MODULO 0x1000
-#define SEQ_MASK   0xfff
-
-static inline int seq_less(u16 sq1, u16 sq2)
-{
-	return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
-}
-
-static inline u16 seq_inc(u16 sq)
-{
-	return (sq + 1) & SEQ_MASK;
-}
-
-static inline u16 seq_sub(u16 sq1, u16 sq2)
-{
-	return (sq1 - sq2) & SEQ_MASK;
-}
-
-
-static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
-					    struct tid_ampdu_rx *tid_agg_rx,
-					    int index)
-{
-	struct ieee80211_supported_band *sband;
-	struct ieee80211_rate *rate = NULL;
-	struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
-	struct ieee80211_rx_status *status;
-
-	if (!skb)
-		goto no_frame;
-
-	status = IEEE80211_SKB_RXCB(skb);
-
-	/* release the reordered frames to stack */
-	sband = hw->wiphy->bands[status->band];
-	if (!(status->flag & RX_FLAG_HT))
-		rate = &sband->bitrates[status->rate_idx];
-	__ieee80211_rx_handle_packet(hw, skb, rate);
-	tid_agg_rx->stored_mpdu_num--;
-	tid_agg_rx->reorder_buf[index] = NULL;
-
-no_frame:
-	tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
-}
-
-static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw,
-					     struct tid_ampdu_rx *tid_agg_rx,
-					     u16 head_seq_num)
-{
-	int index;
-
-	while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
-		index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
-							tid_agg_rx->buf_size;
-		ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
-	}
-}
-
-/*
- * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
- * the skb was added to the buffer longer than this time ago, the earlier
- * frames that have not yet been received are assumed to be lost and the skb
- * can be released for processing. This may also release other skb's from the
- * reorder buffer if there are no additional gaps between the frames.
- */
-#define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
-
-/*
- * As this function belongs to the RX path it must be under
- * rcu_read_lock protection. It returns false if the frame
- * can be processed immediately, true if it was consumed.
- */
-static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
-					     struct tid_ampdu_rx *tid_agg_rx,
-					     struct sk_buff *skb)
-{
-	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
-	u16 sc = le16_to_cpu(hdr->seq_ctrl);
-	u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
-	u16 head_seq_num, buf_size;
-	int index;
-
-	buf_size = tid_agg_rx->buf_size;
-	head_seq_num = tid_agg_rx->head_seq_num;
-
-	/* frame with out of date sequence number */
-	if (seq_less(mpdu_seq_num, head_seq_num)) {
-		dev_kfree_skb(skb);
-		return true;
-	}
-
-	/*
-	 * If frame the sequence number exceeds our buffering window
-	 * size release some previous frames to make room for this one.
-	 */
-	if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) {
-		head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size));
-		/* release stored frames up to new head to stack */
-		ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num);
-	}
-
-	/* Now the new frame is always in the range of the reordering buffer */
-
-	index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size;
-
-	/* check if we already stored this frame */
-	if (tid_agg_rx->reorder_buf[index]) {
-		dev_kfree_skb(skb);
-		return true;
-	}
-
-	/*
-	 * If the current MPDU is in the right order and nothing else
-	 * is stored we can process it directly, no need to buffer it.
-	 */
-	if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
-	    tid_agg_rx->stored_mpdu_num == 0) {
-		tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
-		return false;
-	}
-
-	/* put the frame in the reordering buffer */
-	tid_agg_rx->reorder_buf[index] = skb;
-	tid_agg_rx->reorder_time[index] = jiffies;
-	tid_agg_rx->stored_mpdu_num++;
-	/* release the buffer until next missing frame */
-	index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
-						tid_agg_rx->buf_size;
-	if (!tid_agg_rx->reorder_buf[index] &&
-	    tid_agg_rx->stored_mpdu_num > 1) {
-		/*
-		 * No buffers ready to be released, but check whether any
-		 * frames in the reorder buffer have timed out.
-		 */
-		int j;
-		int skipped = 1;
-		for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
-		     j = (j + 1) % tid_agg_rx->buf_size) {
-			if (!tid_agg_rx->reorder_buf[j]) {
-				skipped++;
-				continue;
-			}
-			if (!time_after(jiffies, tid_agg_rx->reorder_time[j] +
-					HT_RX_REORDER_BUF_TIMEOUT))
-				break;
-
-#ifdef CONFIG_MAC80211_HT_DEBUG
-			if (net_ratelimit())
-				printk(KERN_DEBUG "%s: release an RX reorder "
-				       "frame due to timeout on earlier "
-				       "frames\n",
-				       wiphy_name(hw->wiphy));
-#endif
-			ieee80211_release_reorder_frame(hw, tid_agg_rx, j);
-
-			/*
-			 * Increment the head seq# also for the skipped slots.
-			 */
-			tid_agg_rx->head_seq_num =
-				(tid_agg_rx->head_seq_num + skipped) & SEQ_MASK;
-			skipped = 0;
-		}
-	} else while (tid_agg_rx->reorder_buf[index]) {
-		ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
-		index =	seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
-							tid_agg_rx->buf_size;
-	}
-
-	return true;
-}
-
-/*
- * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
- * true if the MPDU was buffered, false if it should be processed.
- */
-static bool ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
-				       struct sk_buff *skb)
-{
-	struct ieee80211_hw *hw = &local->hw;
-	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
-	struct sta_info *sta;
-	struct tid_ampdu_rx *tid_agg_rx;
-	u16 sc;
-	int tid;
-
-	if (!ieee80211_is_data_qos(hdr->frame_control))
-		return false;
-
-	/*
-	 * filter the QoS data rx stream according to
-	 * STA/TID and check if this STA/TID is on aggregation
-	 */
-
-	sta = sta_info_get(local, hdr->addr2);
-	if (!sta)
-		return false;
-
-	tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
-
-	if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL)
-		return false;
-
-	tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
-
-	/* qos null data frames are excluded */
-	if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
-		return false;
-
-	/* new, potentially un-ordered, ampdu frame - process it */
-
-	/* reset session timer */
-	if (tid_agg_rx->timeout)
-		mod_timer(&tid_agg_rx->session_timer,
-			  TU_TO_EXP_TIME(tid_agg_rx->timeout));
-
-	/* if this mpdu is fragmented - terminate rx aggregation session */
-	sc = le16_to_cpu(hdr->seq_ctrl);
-	if (sc & IEEE80211_SCTL_FRAG) {
-		ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr,
-			tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
-		dev_kfree_skb(skb);
-		return true;
-	}
-
-	return ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb);
-}
-
 /*
  * This is the receive path handler. It is called by a low level driver when an
  * 802.11 MPDU is received from the hardware.