From 252b86c43225d067468dd182e9ae616ad2532bc8 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 16 Nov 2011 15:28:55 +0100 Subject: [PATCH] mac80211: use skb list for fragments We are currently linking the skbs by using skb->next directly. This works, but the preferred way is to use a struct sk_buff_head instead. That also prepares for passing that to drivers directly. While at it I noticed we calculate the duration for fragments twice -- remove one of them. Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- net/mac80211/ieee80211_i.h | 1 + net/mac80211/tx.c | 116 +++++++++++++++++++------------------ net/mac80211/util.c | 6 +- net/mac80211/wep.c | 5 +- net/mac80211/wpa.c | 25 +++++--- 5 files changed, 82 insertions(+), 71 deletions(-) diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index 068cc92d16a..f2785056d8d 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -142,6 +142,7 @@ typedef unsigned __bitwise__ ieee80211_tx_result; struct ieee80211_tx_data { struct sk_buff *skb; + struct sk_buff_head skbs; struct ieee80211_local *local; struct ieee80211_sub_if_data *sdata; struct sta_info *sta; diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 43198836155..26a7cfb80b7 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -35,7 +35,8 @@ /* misc utils */ -static __le16 ieee80211_duration(struct ieee80211_tx_data *tx, int group_addr, +static __le16 ieee80211_duration(struct ieee80211_tx_data *tx, + struct sk_buff *skb, int group_addr, int next_frag_len) { int rate, mrate, erp, dur, i; @@ -43,7 +44,7 @@ static __le16 ieee80211_duration(struct ieee80211_tx_data *tx, int group_addr, struct ieee80211_local *local = tx->local; struct ieee80211_supported_band *sband; struct ieee80211_hdr *hdr; - struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); + struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); /* assume HW handles this */ if (info->control.rates[0].flags & IEEE80211_TX_RC_MCS) @@ -75,7 +76,7 @@ static __le16 ieee80211_duration(struct ieee80211_tx_data *tx, int group_addr, * at the highest possible rate belonging to the PHY rates in the * BSSBasicRateSet */ - hdr = (struct ieee80211_hdr *)tx->skb->data; + hdr = (struct ieee80211_hdr *)skb->data; if (ieee80211_is_ctl(hdr->frame_control)) { /* TODO: These control frames are not currently sent by * mac80211, but should they be implemented, this function @@ -841,11 +842,12 @@ ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx) return TX_CONTINUE; } -static int ieee80211_fragment(struct ieee80211_local *local, +static int ieee80211_fragment(struct ieee80211_tx_data *tx, struct sk_buff *skb, int hdrlen, int frag_threshold) { - struct sk_buff *tail = skb, *tmp; + struct ieee80211_local *local = tx->local; + struct sk_buff *tmp; int per_fragm = frag_threshold - hdrlen - FCS_LEN; int pos = hdrlen + per_fragm; int rem = skb->len - hdrlen - per_fragm; @@ -853,6 +855,8 @@ static int ieee80211_fragment(struct ieee80211_local *local, if (WARN_ON(rem < 0)) return -EINVAL; + /* first fragment was already added to queue by caller */ + while (rem) { int fraglen = per_fragm; @@ -865,8 +869,9 @@ static int ieee80211_fragment(struct ieee80211_local *local, IEEE80211_ENCRYPT_TAILROOM); if (!tmp) return -ENOMEM; - tail->next = tmp; - tail = tmp; + + __skb_queue_tail(&tx->skbs, tmp); + skb_reserve(tmp, local->tx_headroom + IEEE80211_ENCRYPT_HEADROOM); /* copy control information */ @@ -882,6 +887,7 @@ static int ieee80211_fragment(struct ieee80211_local *local, pos += fraglen; } + /* adjust first fragment's length */ skb->len = hdrlen + per_fragm; return 0; } @@ -896,6 +902,10 @@ ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx) int hdrlen; int fragnum; + /* no matter what happens, tx->skb moves to tx->skbs */ + __skb_queue_tail(&tx->skbs, skb); + tx->skb = NULL; + if (info->flags & IEEE80211_TX_CTL_DONTFRAG) return TX_CONTINUE; @@ -924,21 +934,21 @@ ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx) * of the fragments then we will simply pretend to accept the skb * but store it away as pending. */ - if (ieee80211_fragment(tx->local, skb, hdrlen, frag_threshold)) + if (ieee80211_fragment(tx, skb, hdrlen, frag_threshold)) return TX_DROP; /* update duration/seq/flags of fragments */ fragnum = 0; - do { + + skb_queue_walk(&tx->skbs, skb) { int next_len; const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS); hdr = (void *)skb->data; info = IEEE80211_SKB_CB(skb); - if (skb->next) { + if (!skb_queue_is_last(&tx->skbs, skb)) { hdr->frame_control |= morefrags; - next_len = skb->next->len; /* * No multi-rate retries for fragmented frames, that * would completely throw off the NAV at other STAs. @@ -953,10 +963,9 @@ ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx) hdr->frame_control &= ~morefrags; next_len = 0; } - hdr->duration_id = ieee80211_duration(tx, 0, next_len); hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG); fragnum++; - } while ((skb = skb->next)); + } return TX_CONTINUE; } @@ -964,16 +973,16 @@ ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx) static ieee80211_tx_result debug_noinline ieee80211_tx_h_stats(struct ieee80211_tx_data *tx) { - struct sk_buff *skb = tx->skb; + struct sk_buff *skb; if (!tx->sta) return TX_CONTINUE; tx->sta->tx_packets++; - do { + skb_queue_walk(&tx->skbs, skb) { tx->sta->tx_fragments++; tx->sta->tx_bytes += skb->len; - } while ((skb = skb->next)); + } return TX_CONTINUE; } @@ -1012,21 +1021,25 @@ ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx) static ieee80211_tx_result debug_noinline ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx) { - struct sk_buff *skb = tx->skb; + struct sk_buff *skb; struct ieee80211_hdr *hdr; int next_len; bool group_addr; - do { + skb_queue_walk(&tx->skbs, skb) { hdr = (void *) skb->data; if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) break; /* must not overwrite AID */ - next_len = skb->next ? skb->next->len : 0; + if (!skb_queue_is_last(&tx->skbs, skb)) { + struct sk_buff *next = skb_queue_next(&tx->skbs, skb); + next_len = next->len; + } else + next_len = 0; group_addr = is_multicast_ether_addr(hdr->addr1); hdr->duration_id = - ieee80211_duration(tx, group_addr, next_len); - } while ((skb = skb->next)); + ieee80211_duration(tx, skb, group_addr, next_len); + } return TX_CONTINUE; } @@ -1105,6 +1118,7 @@ ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata, tx->local = local; tx->sdata = sdata; tx->channel = local->hw.conf.channel; + __skb_queue_head_init(&tx->skbs); /* * If this flag is set to true anywhere, and we get here, @@ -1180,17 +1194,18 @@ ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata, /* * Returns false if the frame couldn't be transmitted but was queued instead. */ -static bool __ieee80211_tx(struct ieee80211_local *local, struct sk_buff **skbp, +static bool __ieee80211_tx(struct ieee80211_local *local, + struct sk_buff_head *skbs, struct sta_info *sta, bool txpending) { - struct sk_buff *skb = *skbp, *next; + struct sk_buff *skb, *tmp; struct ieee80211_tx_info *info; struct ieee80211_sub_if_data *sdata; unsigned long flags; int len; bool fragm = false; - while (skb) { + skb_queue_walk_safe(skbs, skb, tmp) { int q = skb_get_queue_mapping(skb); __le16 fc; @@ -1202,24 +1217,10 @@ static bool __ieee80211_tx(struct ieee80211_local *local, struct sk_buff **skbp, * transmission from the tx-pending tasklet when the * queue is woken again. */ - - do { - next = skb->next; - skb->next = NULL; - /* - * NB: If txpending is true, next must already - * be NULL since we must've gone through this - * loop before already; therefore we can just - * queue the frame to the head without worrying - * about reordering of fragments. - */ - if (unlikely(txpending)) - __skb_queue_head(&local->pending[q], - skb); - else - __skb_queue_tail(&local->pending[q], - skb); - } while ((skb = next)); + if (txpending) + skb_queue_splice(skbs, &local->pending[q]); + else + skb_queue_splice_tail(skbs, &local->pending[q]); spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); @@ -1233,10 +1234,9 @@ static bool __ieee80211_tx(struct ieee80211_local *local, struct sk_buff **skbp, info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT | IEEE80211_TX_CTL_FIRST_FRAGMENT); - next = skb->next; len = skb->len; - if (next) + if (!skb_queue_is_last(skbs, skb)) info->flags |= IEEE80211_TX_CTL_MORE_FRAMES; sdata = vif_to_sdata(info->control.vif); @@ -1260,14 +1260,17 @@ static bool __ieee80211_tx(struct ieee80211_local *local, struct sk_buff **skbp, info->control.sta = NULL; fc = ((struct ieee80211_hdr *)skb->data)->frame_control; + + __skb_unlink(skb, skbs); drv_tx(local, skb); ieee80211_tpt_led_trig_tx(local, fc, len); - *skbp = skb = next; ieee80211_led_tx(local, 1); fragm = true; } + WARN_ON(!skb_queue_empty(skbs)); + return true; } @@ -1277,8 +1280,7 @@ static bool __ieee80211_tx(struct ieee80211_local *local, struct sk_buff **skbp, */ static int invoke_tx_handlers(struct ieee80211_tx_data *tx) { - struct sk_buff *skb = tx->skb; - struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); + struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb); ieee80211_tx_result res = TX_DROP; #define CALL_TXH(txh) \ @@ -1312,13 +1314,10 @@ static int invoke_tx_handlers(struct ieee80211_tx_data *tx) txh_done: if (unlikely(res == TX_DROP)) { I802_DEBUG_INC(tx->local->tx_handlers_drop); - while (skb) { - struct sk_buff *next; - - next = skb->next; - dev_kfree_skb(skb); - skb = next; - } + if (tx->skb) + dev_kfree_skb(tx->skb); + else + __skb_queue_purge(&tx->skbs); return -1; } else if (unlikely(res == TX_QUEUED)) { I802_DEBUG_INC(tx->local->tx_handlers_queued); @@ -1361,7 +1360,7 @@ static bool ieee80211_tx(struct ieee80211_sub_if_data *sdata, info->band = tx.channel->band; if (!invoke_tx_handlers(&tx)) - result = __ieee80211_tx(local, &tx.skb, tx.sta, txpending); + result = __ieee80211_tx(local, &tx.skbs, tx.sta, txpending); out: rcu_read_unlock(); return result; @@ -2109,10 +2108,15 @@ static bool ieee80211_tx_pending_skb(struct ieee80211_local *local, if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) { result = ieee80211_tx(sdata, skb, true); } else { + struct sk_buff_head skbs; + + __skb_queue_head_init(&skbs); + __skb_queue_tail(&skbs, skb); + hdr = (struct ieee80211_hdr *)skb->data; sta = sta_info_get(sdata, hdr->addr1); - result = __ieee80211_tx(local, &skb, sta, true); + result = __ieee80211_tx(local, &skbs, sta, true); } return result; diff --git a/net/mac80211/util.c b/net/mac80211/util.c index 4cf25b0eea7..939bf248ec7 100644 --- a/net/mac80211/util.c +++ b/net/mac80211/util.c @@ -95,13 +95,13 @@ u8 *ieee80211_get_bssid(struct ieee80211_hdr *hdr, size_t len, void ieee80211_tx_set_protected(struct ieee80211_tx_data *tx) { - struct sk_buff *skb = tx->skb; + struct sk_buff *skb; struct ieee80211_hdr *hdr; - do { + skb_queue_walk(&tx->skbs, skb) { hdr = (struct ieee80211_hdr *) skb->data; hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); - } while ((skb = skb->next)); + } } int ieee80211_frame_duration(struct ieee80211_local *local, size_t len, diff --git a/net/mac80211/wep.c b/net/mac80211/wep.c index a1c6bfd55f0..68ad351479d 100644 --- a/net/mac80211/wep.c +++ b/net/mac80211/wep.c @@ -330,13 +330,12 @@ ieee80211_crypto_wep_encrypt(struct ieee80211_tx_data *tx) ieee80211_tx_set_protected(tx); - skb = tx->skb; - do { + skb_queue_walk(&tx->skbs, skb) { if (wep_encrypt_skb(tx, skb) < 0) { I802_DEBUG_INC(tx->local->tx_handlers_drop_wep); return TX_DROP; } - } while ((skb = skb->next)); + } return TX_CONTINUE; } diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c index 106e15a4649..93aab0715e8 100644 --- a/net/mac80211/wpa.c +++ b/net/mac80211/wpa.c @@ -223,14 +223,14 @@ static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) ieee80211_tx_result ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx) { - struct sk_buff *skb = tx->skb; + struct sk_buff *skb; ieee80211_tx_set_protected(tx); - do { + skb_queue_walk(&tx->skbs, skb) { if (tkip_encrypt_skb(tx, skb) < 0) return TX_DROP; - } while ((skb = skb->next)); + } return TX_CONTINUE; } @@ -449,14 +449,14 @@ static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) ieee80211_tx_result ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx) { - struct sk_buff *skb = tx->skb; + struct sk_buff *skb; ieee80211_tx_set_protected(tx); - do { + skb_queue_walk(&tx->skbs, skb) { if (ccmp_encrypt_skb(tx, skb) < 0) return TX_DROP; - } while ((skb = skb->next)); + } return TX_CONTINUE; } @@ -554,15 +554,22 @@ static inline void bip_ipn_swap(u8 *d, const u8 *s) ieee80211_tx_result ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx) { - struct sk_buff *skb = tx->skb; - struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); + struct sk_buff *skb; + struct ieee80211_tx_info *info; struct ieee80211_key *key = tx->key; struct ieee80211_mmie *mmie; u8 aad[20]; u64 pn64; + if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) + return TX_DROP; + + skb = skb_peek(&tx->skbs); + + info = IEEE80211_SKB_CB(skb); + if (info->control.hw_key) - return 0; + return TX_CONTINUE; if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) return TX_DROP; -- 2.20.1