[1/2] mac80211: add A-MSDU tx support

Message ID	1455820762-22876-1-git-send-email-nbd@openwrt.org (mailing list archive)
State	Changes Requested
Delegated to:	Johannes Berg
Headers	show Return-Path: <linux-wireless-owner@kernel.org> From: Felix Fietkau <nbd@openwrt.org> To: linux-wireless@vger.kernel.org Cc: johannes@sipsolutions.net, egrumbach@gmail.com Subject: [PATCH 1/2] mac80211: add A-MSDU tx support Date: Thu, 18 Feb 2016 19:39:21 +0100 Message-Id: <1455820762-22876-1-git-send-email-nbd@openwrt.org> Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk

diff --git a/include/net/mac80211.h b/include/net/mac80211.h index 5714774..720ccb0 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -709,6 +709,7 @@ enum mac80211_tx_info_flags { * @IEEE80211_TX_CTRL_PS_RESPONSE: This frame is a response to a poll * frame (PS-Poll or uAPSD). * @IEEE80211_TX_CTRL_RATE_INJECT: This frame is injected with rate information + * @IEEE80211_TX_CTRL_AMSDU: This frame is an A-MSDU frame * * These flags are used in tx_info->control.flags. */ @@ -716,6 +717,7 @@ enum mac80211_tx_control_flags { IEEE80211_TX_CTRL_PORT_CTRL_PROTO = BIT(0), IEEE80211_TX_CTRL_PS_RESPONSE = BIT(1), IEEE80211_TX_CTRL_RATE_INJECT = BIT(2), + IEEE80211_TX_CTRL_AMSDU = BIT(3), }; /* @@ -1731,6 +1733,7 @@ struct ieee80211_sta_rates { * size is min(max_amsdu_len, 7935) bytes. * Both additional HT limits must be enforced by the low level driver. * This is defined by the spec (IEEE 802.11-2012 section 8.3.2.2 NOTE 2). + * @max_rc_amsdu_len: Maximum A-MSDU size in bytes recommended by rate control. * @txq: per-TID data TX queues (if driver uses the TXQ abstraction) */ struct ieee80211_sta { @@ -1751,6 +1754,7 @@ struct ieee80211_sta { bool mfp; u8 max_amsdu_subframes; u16 max_amsdu_len; + u16 max_rc_amsdu_len; struct ieee80211_txq *txq[IEEE80211_NUM_TIDS]; @@ -1964,6 +1968,12 @@ struct ieee80211_txq { * order and does not need to manage its own reorder buffer or BA session * timeout. * + * @IEEE80211_HW_TX_AMSDU: Hardware (or driver) supports software aggregated + * A-MSDU frames. Requires software tx queueing support. + * + * @IEEE80211_HW_TX_FRAG_LIST: Hardware (or driver) supports sending frag_list + * skbs, needed for zero-copy software A-MSDU. + * * @NUM_IEEE80211_HW_FLAGS: number of hardware flags, used for sizing arrays */ enum ieee80211_hw_flags { @@ -2001,6 +2011,8 @@ enum ieee80211_hw_flags { IEEE80211_HW_BEACON_TX_STATUS, IEEE80211_HW_NEEDS_UNIQUE_STA_ADDR, IEEE80211_HW_SUPPORTS_REORDERING_BUFFER, + IEEE80211_HW_TX_AMSDU, + IEEE80211_HW_TX_FRAG_LIST, /* keep last, obviously */ NUM_IEEE80211_HW_FLAGS @@ -2073,6 +2085,8 @@ enum ieee80211_hw_flags { * size is smaller (an example is LinkSys WRT120N with FW v1.0.07 * build 002 Jun 18 2012). * + * @max_tx_fragments: maximum fragments per (A-)MSDU. + * * @offchannel_tx_hw_queue: HW queue ID to use for offchannel TX * (if %IEEE80211_HW_QUEUE_CONTROL is set) * @@ -2127,6 +2141,7 @@ struct ieee80211_hw { u8 max_rate_tries; u8 max_rx_aggregation_subframes; u8 max_tx_aggregation_subframes; + u8 max_tx_fragments; u8 offchannel_tx_hw_queue; u8 radiotap_mcs_details; u16 radiotap_vht_details; diff --git a/net/mac80211/agg-tx.c b/net/mac80211/agg-tx.c index 4932e9f..42fa810 100644 --- a/net/mac80211/agg-tx.c +++ b/net/mac80211/agg-tx.c @@ -935,6 +935,7 @@ void ieee80211_process_addba_resp(struct ieee80211_local *local, size_t len) { struct tid_ampdu_tx *tid_tx; + struct ieee80211_txq *txq; u16 capab, tid; u8 buf_size; bool amsdu; @@ -945,6 +946,10 @@ void ieee80211_process_addba_resp(struct ieee80211_local *local, buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6; buf_size = min(buf_size, local->hw.max_tx_aggregation_subframes); + txq = sta->sta.txq[tid]; + if (!amsdu && txq) + set_bit(IEEE80211_TXQ_NO_AMSDU, &to_txq_info(txq)->flags); + mutex_lock(&sta->ampdu_mlme.mtx); tid_tx = rcu_dereference_protected_tid_tx(sta, tid); diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c index e433d0c..847779d 100644 --- a/net/mac80211/debugfs.c +++ b/net/mac80211/debugfs.c @@ -127,6 +127,8 @@ static const char *hw_flag_names[NUM_IEEE80211_HW_FLAGS + 1] = { FLAG(BEACON_TX_STATUS), FLAG(NEEDS_UNIQUE_STA_ADDR), FLAG(SUPPORTS_REORDERING_BUFFER), + FLAG(TX_AMSDU), + FLAG(TX_FRAG_LIST), /* keep last for the build bug below */ (void *)0x1 diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index a49c103..e68d8db 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -799,6 +799,7 @@ struct mac80211_qos_map { enum txq_info_flags { IEEE80211_TXQ_STOP, IEEE80211_TXQ_AMPDU, + IEEE80211_TXQ_NO_AMSDU, }; struct txq_info { diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 7bb67fa9..a4108b7 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -1324,6 +1324,10 @@ struct sk_buff *ieee80211_tx_dequeue(struct ieee80211_hw *hw, out: spin_unlock_bh(&txqi->queue.lock); + if (skb && skb_has_frag_list(skb) && + !ieee80211_hw_check(&local->hw, TX_FRAG_LIST)) + skb_linearize(skb); + return skb; } EXPORT_SYMBOL(ieee80211_tx_dequeue); @@ -2766,6 +2770,165 @@ void ieee80211_clear_fast_xmit(struct sta_info *sta) kfree_rcu(fast_tx, rcu_head); } +static int ieee80211_amsdu_pad(struct sk_buff *skb, int subframe_len) +{ + int amsdu_len = subframe_len + sizeof(struct ethhdr); + int padding = (4 - amsdu_len) & 3; + + if (padding) + memset(skb_put(skb, padding), 0, padding); + + return padding; +} + +static bool ieee80211_amsdu_prepare_head(struct ieee80211_sub_if_data *sdata, + struct ieee80211_fast_tx *fast_tx, + struct sk_buff *skb) +{ + struct ieee80211_local *local = sdata->local; + struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); + struct ieee80211_hdr *hdr; + struct ethhdr amsdu_hdr; + int hdr_len = fast_tx->hdr_len - sizeof(rfc1042_header); + int subframe_len = skb->len - hdr_len; + void *data; + u8 *qc; + + if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE) + return false; + + if (info->control.flags & IEEE80211_TX_CTRL_AMSDU) + return true; + + if (skb_headroom(skb) < sizeof(amsdu_hdr) || skb_tailroom(skb) < 3) { + I802_DEBUG_INC(local->tx_expand_skb_head); + + if (pskb_expand_head(skb, sizeof(amsdu_hdr), 3, GFP_ATOMIC)) { + wiphy_debug(local->hw.wiphy, + "failed to reallocate TX buffer\n"); + return false; + } + } + + subframe_len += ieee80211_amsdu_pad(skb, subframe_len); + + amsdu_hdr.h_proto = cpu_to_be16(subframe_len); + memcpy(amsdu_hdr.h_source, skb->data + fast_tx->sa_offs, ETH_ALEN); + memcpy(amsdu_hdr.h_dest, skb->data + fast_tx->da_offs, ETH_ALEN); + + data = skb_push(skb, sizeof(amsdu_hdr)); + memmove(data, data + sizeof(amsdu_hdr), hdr_len); + memcpy(data + hdr_len, &amsdu_hdr, sizeof(amsdu_hdr)); + + hdr = data; + qc = ieee80211_get_qos_ctl(hdr); + *qc |= IEEE80211_QOS_CTL_A_MSDU_PRESENT; + + info->control.flags |= IEEE80211_TX_CTRL_AMSDU; + + return true; +} + +static bool ieee80211_amsdu_aggregate(struct ieee80211_sub_if_data *sdata, + struct sta_info *sta, + struct ieee80211_fast_tx *fast_tx, + struct sk_buff *skb) +{ + struct ieee80211_local *local = sdata->local; + u8 tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK; + struct ieee80211_txq *txq = sta->sta.txq[tid]; + struct txq_info *txqi; + struct sk_buff **frag_tail, *head; + int subframe_len = skb->len - ETH_ALEN; + u8 max_subframes = sta->sta.max_amsdu_subframes; + int max_frags = local->hw.max_tx_fragments; + int max_amsdu_len = sta->sta.max_amsdu_len; + __be16 len; + void *data; + bool ret = false; + int n = 1, nfrags; + + if (!ieee80211_hw_check(&local->hw, TX_AMSDU)) + return false; + + if (!txq) + return false; + + txqi = to_txq_info(txq); + if (test_bit(IEEE80211_TXQ_NO_AMSDU, &txqi->flags)) + return false; + + if (sta->sta.max_rc_amsdu_len) + max_amsdu_len = min_t(int, max_amsdu_len, + sta->sta.max_rc_amsdu_len); + + spin_lock_bh(&txqi->queue.lock); + + head = skb_peek_tail(&txqi->queue); + if (!head) + goto out; + + if (skb->len + head->len > max_amsdu_len) + goto out; + + /* + * HT A-MPDU limits maximum MPDU size to 4095 bytes. Since aggregation + * sessions are started/stopped without txq flush, use the limit here + * to avoid having to de-aggregate later. + */ + if (skb->len + head->len > 4095 && + !sta->sta.vht_cap.vht_supported) + goto out; + + if (!ieee80211_amsdu_prepare_head(sdata, fast_tx, head)) + goto out; + + nfrags = 1 + skb_shinfo(skb)->nr_frags; + nfrags += 1 + skb_shinfo(head)->nr_frags; + frag_tail = &skb_shinfo(head)->frag_list; + while (*frag_tail) { + nfrags += 1 + skb_shinfo(*frag_tail)->nr_frags; + frag_tail = &(*frag_tail)->next; + n++; + } + + if (max_subframes && n > max_subframes) + goto out; + + if (max_frags && nfrags > max_frags) + goto out; + + if (skb_headroom(skb) < 8 || skb_tailroom(skb) < 3) { + I802_DEBUG_INC(local->tx_expand_skb_head); + + if (pskb_expand_head(skb, 8, 3, GFP_ATOMIC)) { + wiphy_debug(local->hw.wiphy, + "failed to reallocate TX buffer\n"); + goto out; + } + } + + subframe_len += ieee80211_amsdu_pad(skb, subframe_len); + + ret = true; + data = skb_push(skb, ETH_ALEN + 2); + memmove(data, data + ETH_ALEN + 2, 2 * ETH_ALEN); + + data += 2 * ETH_ALEN; + len = cpu_to_be16(subframe_len); + memcpy(data, &len, 2); + memcpy(data + 2, rfc1042_header, ETH_ALEN); + + head->len += skb->len; + head->data_len += skb->len; + *frag_tail = skb; + +out: + spin_unlock_bh(&txqi->queue.lock); + + return ret; +} + static bool ieee80211_xmit_fast(struct ieee80211_sub_if_data *sdata, struct net_device *dev, struct sta_info *sta, struct ieee80211_fast_tx *fast_tx, @@ -2820,6 +2983,10 @@ static bool ieee80211_xmit_fast(struct ieee80211_sub_if_data *sdata, ieee80211_tx_stats(dev, skb->len + extra_head); + if ((hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_QOS_DATA)) && + ieee80211_amsdu_aggregate(sdata, sta, fast_tx, skb)) + return true; + /* will not be crypto-handled beyond what we do here, so use false * as the may-encrypt argument for the resize to not account for * more room than we already have in 'extra_head'

[1/2] mac80211: add A-MSDU tx support

Commit Message

Comments

Patch