Commit b580781e authored by Ron Rindjunsky's avatar Ron Rindjunsky Committed by David S. Miller

mac80211: A-MPDU Rx handling aggregation reordering

This patch handles the reordering of the Rx A-MPDU.
This issue occurs when the sequence of the internal MPDUs is not in the
right order. such a case can be encountered for example when some MPDUs from
previous aggregations were recieved, while others failed, so current A-MPDU
will contain a mix of re-transmited MPDUs and new ones.
Signed-off-by: default avatarRon Rindjunsky <ron.rindjunsky@intel.com>
Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 16c5f15c
......@@ -1208,7 +1208,7 @@ void ieee80211_sta_stop_rx_ba_session(struct net_device *dev, u8 *ra, u16 tid,
struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
struct ieee80211_hw *hw = &local->hw;
struct sta_info *sta;
int ret;
int ret, i;
sta = sta_info_get(local, ra);
if (!sta)
......@@ -1250,6 +1250,14 @@ void ieee80211_sta_stop_rx_ba_session(struct net_device *dev, u8 *ra, u16 tid,
ieee80211_send_delba(dev, ra, tid, 0, reason);
/* free the reordering buffer */
for (i = 0; i < sta->ampdu_mlme.tid_rx[tid].buf_size; i++) {
if (sta->ampdu_mlme.tid_rx[tid].reorder_buf[i]) {
/* release the reordered frames */
dev_kfree_skb(sta->ampdu_mlme.tid_rx[tid].reorder_buf[i]);
sta->ampdu_mlme.tid_rx[tid].stored_mpdu_num--;
sta->ampdu_mlme.tid_rx[tid].reorder_buf[i] = NULL;
}
}
kfree(sta->ampdu_mlme.tid_rx[tid].reorder_buf);
sta->ampdu_mlme.tid_rx[tid].state = HT_AGG_STATE_IDLE;
......
......@@ -330,7 +330,6 @@ u32 ieee80211_rx_load_stats(struct ieee80211_local *local,
/* Divide channel_use by 8 to avoid wrapping around the counter */
load >>= CHAN_UTIL_SHIFT;
local->channel_use_raw += load;
return load;
}
......@@ -1749,6 +1748,186 @@ void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw, struct sk_buff *skb,
sta_info_put(sta);
}
#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);
}
u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
struct tid_ampdu_rx *tid_agg_rx,
struct sk_buff *skb, u16 mpdu_seq_num,
int bar_req)
{
struct ieee80211_local *local = hw_to_local(hw);
struct ieee80211_rx_status status;
u16 head_seq_num, buf_size;
int index;
u32 pkt_load;
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 1;
}
/* if frame sequence number exceeds our buffering window size or
* block Ack Request arrived - release stored frames */
if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
/* new head to the ordering buffer */
if (bar_req)
head_seq_num = mpdu_seq_num;
else
head_seq_num =
seq_inc(seq_sub(mpdu_seq_num, buf_size));
/* release stored frames up to new head to stack */
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;
if (tid_agg_rx->reorder_buf[index]) {
/* release the reordered frames to stack */
memcpy(&status,
tid_agg_rx->reorder_buf[index]->cb,
sizeof(status));
pkt_load = ieee80211_rx_load_stats(local,
tid_agg_rx->reorder_buf[index],
&status);
__ieee80211_rx_handle_packet(hw,
tid_agg_rx->reorder_buf[index],
&status, pkt_load);
tid_agg_rx->stored_mpdu_num--;
tid_agg_rx->reorder_buf[index] = NULL;
}
tid_agg_rx->head_seq_num =
seq_inc(tid_agg_rx->head_seq_num);
}
if (bar_req)
return 1;
}
/* now the new frame is always in the range of the reordering */
/* buffer window */
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 1;
}
/* if arrived mpdu is in the right order and nothing else stored */
/* release it immediately */
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 0;
}
/* put the frame in the reordering buffer */
tid_agg_rx->reorder_buf[index] = skb;
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;
while (tid_agg_rx->reorder_buf[index]) {
/* release the reordered frame back to stack */
memcpy(&status, tid_agg_rx->reorder_buf[index]->cb,
sizeof(status));
pkt_load = ieee80211_rx_load_stats(local,
tid_agg_rx->reorder_buf[index],
&status);
__ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index],
&status, pkt_load);
tid_agg_rx->stored_mpdu_num--;
tid_agg_rx->reorder_buf[index] = NULL;
tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
index = seq_sub(tid_agg_rx->head_seq_num,
tid_agg_rx->ssn) % tid_agg_rx->buf_size;
}
return 1;
}
u8 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 fc, sc;
u16 mpdu_seq_num;
u8 ret = 0, *qc;
int tid;
sta = sta_info_get(local, hdr->addr2);
if (!sta)
return ret;
fc = le16_to_cpu(hdr->frame_control);
/* filter the QoS data rx stream according to
* STA/TID and check if this STA/TID is on aggregation */
if (!WLAN_FC_IS_QOS_DATA(fc))
goto end_reorder;
qc = skb->data + ieee80211_get_hdrlen(fc) - QOS_CONTROL_LEN;
tid = qc[0] & QOS_CONTROL_TID_MASK;
tid_agg_rx = &(sta->ampdu_mlme.tid_rx[tid]);
if (tid_agg_rx->state != HT_AGG_STATE_OPERATIONAL)
goto end_reorder;
/* null data frames are excluded */
if (unlikely(fc & IEEE80211_STYPE_QOS_NULLFUNC))
goto end_reorder;
/* new un-ordered ampdu frame - process it */
/* reset session timer */
if (tid_agg_rx->timeout) {
unsigned long expires =
jiffies + (tid_agg_rx->timeout / 1000) * HZ;
mod_timer(&tid_agg_rx->session_timer, expires);
}
/* 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->dev, sta->addr,
tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
ret = 1;
goto end_reorder;
}
/* according to mpdu sequence number deal with reordering buffer */
mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb,
mpdu_seq_num, 0);
end_reorder:
if (sta)
sta_info_put(sta);
return ret;
}
/*
* This is the receive path handler. It is called by a low level driver when an
* 802.11 MPDU is received from the hardware.
......@@ -1779,8 +1958,10 @@ void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
}
pkt_load = ieee80211_rx_load_stats(local, skb, status);
local->channel_use_raw += pkt_load;
__ieee80211_rx_handle_packet(hw, skb, status, pkt_load);
if (!ieee80211_rx_reorder_ampdu(local, skb))
__ieee80211_rx_handle_packet(hw, skb, status, pkt_load);
rcu_read_unlock();
}
......
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