diff options
Diffstat (limited to 'net/mac80211')
-rw-r--r-- | net/mac80211/rx.c | 459 |
1 files changed, 229 insertions, 230 deletions
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index 097bb03..d71a63e 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -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_rx_data *rx) 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(struct ieee80211_hw *hw, 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. |