From 83eb935ec74a91468776cd86415abcb6ee23cca8 Mon Sep 17 00:00:00 2001 From: Michal Kazior Date: Wed, 16 Jul 2014 12:09:31 +0200 Subject: [PATCH] mac80211: fix Rx reordering with RX_FLAG_AMSDU_MORE Some drivers (e.g. ath10k) report A-MSDU subframes individually with identical seqno. The A-MPDU Rx reorder code did not account for that which made it practically unusable with drivers using RX_FLAG_AMSDU_MORE because it would end up dropping a lot of frames resulting in confusion in upper network transport layers. Signed-off-by: Michal Kazior Signed-off-by: Johannes Berg --- net/mac80211/agg-rx.c | 9 ++++-- net/mac80211/ieee80211_i.h | 15 ++++++++++ net/mac80211/rx.c | 57 +++++++++++++++++++++++++------------- net/mac80211/sta_info.h | 5 ++-- 4 files changed, 62 insertions(+), 24 deletions(-) diff --git a/net/mac80211/agg-rx.c b/net/mac80211/agg-rx.c index 31bf2586fb84..d38c49b644cd 100644 --- a/net/mac80211/agg-rx.c +++ b/net/mac80211/agg-rx.c @@ -52,7 +52,7 @@ static void ieee80211_free_tid_rx(struct rcu_head *h) del_timer_sync(&tid_rx->reorder_timer); for (i = 0; i < tid_rx->buf_size; i++) - dev_kfree_skb(tid_rx->reorder_buf[i]); + __skb_queue_purge(&tid_rx->reorder_buf[i]); kfree(tid_rx->reorder_buf); kfree(tid_rx->reorder_time); kfree(tid_rx); @@ -232,7 +232,7 @@ void ieee80211_process_addba_request(struct ieee80211_local *local, struct tid_ampdu_rx *tid_agg_rx; u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num, status; u8 dialog_token; - int ret = -EOPNOTSUPP; + int i, ret = -EOPNOTSUPP; /* extract session parameters from addba request frame */ dialog_token = mgmt->u.action.u.addba_req.dialog_token; @@ -308,7 +308,7 @@ void ieee80211_process_addba_request(struct ieee80211_local *local, /* prepare reordering buffer */ tid_agg_rx->reorder_buf = - kcalloc(buf_size, sizeof(struct sk_buff *), GFP_KERNEL); + kcalloc(buf_size, sizeof(struct sk_buff_head), GFP_KERNEL); tid_agg_rx->reorder_time = kcalloc(buf_size, sizeof(unsigned long), GFP_KERNEL); if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) { @@ -318,6 +318,9 @@ void ieee80211_process_addba_request(struct ieee80211_local *local, goto end; } + for (i = 0; i < buf_size; i++) + __skb_queue_head_init(&tid_agg_rx->reorder_buf[i]); + ret = drv_ampdu_action(local, sta->sdata, IEEE80211_AMPDU_RX_START, &sta->sta, tid, &start_seq_num, 0); ht_dbg(sta->sdata, "Rx A-MPDU request on %pM tid %d result %d\n", diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index 49731dd044bb..c504e99a5404 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -1729,6 +1729,21 @@ static inline void ieee802_11_parse_elems(const u8 *start, size_t len, ieee802_11_parse_elems_crc(start, len, action, elems, 0, 0); } +static inline bool ieee80211_rx_reorder_ready(struct sk_buff_head *frames) +{ + struct sk_buff *tail = skb_peek_tail(frames); + struct ieee80211_rx_status *status; + + if (!tail) + return false; + + status = IEEE80211_SKB_RXCB(tail); + if (status->flag & RX_FLAG_AMSDU_MORE) + return false; + + return true; +} + void ieee80211_dynamic_ps_enable_work(struct work_struct *work); void ieee80211_dynamic_ps_disable_work(struct work_struct *work); void ieee80211_dynamic_ps_timer(unsigned long data); diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index 5a786d489f7e..bd2c9b22c945 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -688,20 +688,27 @@ static void ieee80211_release_reorder_frame(struct ieee80211_sub_if_data *sdata, int index, struct sk_buff_head *frames) { - struct sk_buff *skb = tid_agg_rx->reorder_buf[index]; + struct sk_buff_head *skb_list = &tid_agg_rx->reorder_buf[index]; + struct sk_buff *skb; struct ieee80211_rx_status *status; lockdep_assert_held(&tid_agg_rx->reorder_lock); - if (!skb) + if (skb_queue_empty(skb_list)) goto no_frame; - /* release the frame from the reorder ring buffer */ + if (!ieee80211_rx_reorder_ready(skb_list)) { + __skb_queue_purge(skb_list); + goto no_frame; + } + + /* release frames from the reorder ring buffer */ tid_agg_rx->stored_mpdu_num--; - tid_agg_rx->reorder_buf[index] = NULL; - status = IEEE80211_SKB_RXCB(skb); - status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE; - __skb_queue_tail(frames, skb); + while ((skb = __skb_dequeue(skb_list))) { + status = IEEE80211_SKB_RXCB(skb); + status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE; + __skb_queue_tail(frames, skb); + } no_frame: tid_agg_rx->head_seq_num = ieee80211_sn_inc(tid_agg_rx->head_seq_num); @@ -738,13 +745,13 @@ static void ieee80211_sta_reorder_release(struct ieee80211_sub_if_data *sdata, struct tid_ampdu_rx *tid_agg_rx, struct sk_buff_head *frames) { - int index, j; + int index, i, j; lockdep_assert_held(&tid_agg_rx->reorder_lock); /* release the buffer until next missing frame */ index = tid_agg_rx->head_seq_num % tid_agg_rx->buf_size; - if (!tid_agg_rx->reorder_buf[index] && + if (!ieee80211_rx_reorder_ready(&tid_agg_rx->reorder_buf[index]) && tid_agg_rx->stored_mpdu_num) { /* * No buffers ready to be released, but check whether any @@ -753,7 +760,8 @@ static void ieee80211_sta_reorder_release(struct ieee80211_sub_if_data *sdata, 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]) { + if (!ieee80211_rx_reorder_ready( + &tid_agg_rx->reorder_buf[j])) { skipped++; continue; } @@ -762,6 +770,11 @@ static void ieee80211_sta_reorder_release(struct ieee80211_sub_if_data *sdata, HT_RX_REORDER_BUF_TIMEOUT)) goto set_release_timer; + /* don't leave incomplete A-MSDUs around */ + for (i = (index + 1) % tid_agg_rx->buf_size; i != j; + i = (i + 1) % tid_agg_rx->buf_size) + __skb_queue_purge(&tid_agg_rx->reorder_buf[i]); + ht_dbg_ratelimited(sdata, "release an RX reorder frame due to timeout on earlier frames\n"); ieee80211_release_reorder_frame(sdata, tid_agg_rx, j, @@ -775,7 +788,8 @@ static void ieee80211_sta_reorder_release(struct ieee80211_sub_if_data *sdata, skipped) & IEEE80211_SN_MASK; skipped = 0; } - } else while (tid_agg_rx->reorder_buf[index]) { + } else while (ieee80211_rx_reorder_ready( + &tid_agg_rx->reorder_buf[index])) { ieee80211_release_reorder_frame(sdata, tid_agg_rx, index, frames); index = tid_agg_rx->head_seq_num % tid_agg_rx->buf_size; @@ -786,7 +800,8 @@ static void ieee80211_sta_reorder_release(struct ieee80211_sub_if_data *sdata, for (; j != (index - 1) % tid_agg_rx->buf_size; j = (j + 1) % tid_agg_rx->buf_size) { - if (tid_agg_rx->reorder_buf[j]) + if (ieee80211_rx_reorder_ready( + &tid_agg_rx->reorder_buf[j])) break; } @@ -811,6 +826,7 @@ static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_sub_if_data *sdata struct sk_buff_head *frames) { struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; + struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); u16 sc = le16_to_cpu(hdr->seq_ctrl); u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4; u16 head_seq_num, buf_size; @@ -845,7 +861,7 @@ static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_sub_if_data *sdata index = mpdu_seq_num % tid_agg_rx->buf_size; /* check if we already stored this frame */ - if (tid_agg_rx->reorder_buf[index]) { + if (ieee80211_rx_reorder_ready(&tid_agg_rx->reorder_buf[index])) { dev_kfree_skb(skb); goto out; } @@ -858,17 +874,20 @@ static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_sub_if_data *sdata */ if (mpdu_seq_num == tid_agg_rx->head_seq_num && tid_agg_rx->stored_mpdu_num == 0) { - tid_agg_rx->head_seq_num = - ieee80211_sn_inc(tid_agg_rx->head_seq_num); + if (!(status->flag & RX_FLAG_AMSDU_MORE)) + tid_agg_rx->head_seq_num = + ieee80211_sn_inc(tid_agg_rx->head_seq_num); ret = false; goto out; } /* 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++; - ieee80211_sta_reorder_release(sdata, tid_agg_rx, frames); + __skb_queue_tail(&tid_agg_rx->reorder_buf[index], skb); + if (!(status->flag & RX_FLAG_AMSDU_MORE)) { + tid_agg_rx->reorder_time[index] = jiffies; + tid_agg_rx->stored_mpdu_num++; + ieee80211_sta_reorder_release(sdata, tid_agg_rx, frames); + } out: spin_unlock(&tid_agg_rx->reorder_lock); diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h index e37f00969526..d411bcc8ef08 100644 --- a/net/mac80211/sta_info.h +++ b/net/mac80211/sta_info.h @@ -155,7 +155,8 @@ struct tid_ampdu_tx { /** * struct tid_ampdu_rx - TID aggregation information (Rx). * - * @reorder_buf: buffer to reorder incoming aggregated MPDUs + * @reorder_buf: buffer to reorder incoming aggregated MPDUs. An MPDU may be an + * A-MSDU with individually reported subframes. * @reorder_time: jiffies when skb was added * @session_timer: check if peer keeps Tx-ing on the TID (by timeout value) * @reorder_timer: releases expired frames from the reorder buffer. @@ -180,7 +181,7 @@ struct tid_ampdu_tx { struct tid_ampdu_rx { struct rcu_head rcu_head; spinlock_t reorder_lock; - struct sk_buff **reorder_buf; + struct sk_buff_head *reorder_buf; unsigned long *reorder_time; struct timer_list session_timer; struct timer_list reorder_timer; -- 2.39.2