mac80211: transmit fragment list to drivers

Drivers can usually handle fragmented packets
much easier when they get the entire list of
fragments at once. The only thing they need to
do is keep enough space on the queues for up
to ten fragments of a single MSDU.

This allows them to implement this with a new
operation tx_frags.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

3 files changed, 69 insertions, 35 deletions

diff --git a/net/mac80211/driver-ops.h b/net/mac80211/driver-ops.h
index b12ed52732c8..49cc5e0e8a6a 100644
--- a/net/mac80211/driver-ops.h
+++ b/net/mac80211/driver-ops.h
@@ -15,6 +15,14 @@ static inline void drv_tx(struct ieee80211_local *local, struct sk_buff *skb)
         local->ops->tx(&local->hw, skb);
 }
 
+static inline void drv_tx_frags(struct ieee80211_local *local,
+                                struct ieee80211_vif *vif,
+                                struct ieee80211_sta *sta,
+                                struct sk_buff_head *skbs)
+{
+        local->ops->tx_frags(&local->hw, vif, sta, skbs);
+}
+
 static inline int drv_start(struct ieee80211_local *local)
 {
         int ret;
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index e323d4e6647b..3df4482bb1d9 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -609,7 +609,7 @@ struct ieee80211_hw *ieee80211_alloc_hw(size_t priv_data_len,
 
         local->hw.priv = (char *)local + ALIGN(sizeof(*local), NETDEV_ALIGN);
 
-        BUG_ON(!ops->tx);
+        BUG_ON(!ops->tx && !ops->tx_frags);
         BUG_ON(!ops->start);
         BUG_ON(!ops->stop);
         BUG_ON(!ops->config);
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 0cc68d0796a2..facc80d23b0c 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -1200,24 +1200,15 @@ ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata,
         return TX_CONTINUE;
 }
 
-/*
- * Returns false if the frame couldn't be transmitted but was queued instead.
- */
-static bool __ieee80211_tx(struct ieee80211_local *local,
-                           struct sk_buff_head *skbs, int led_len,
-                           struct sta_info *sta, bool txpending)
+static bool ieee80211_tx_frags(struct ieee80211_local *local,
+                               struct ieee80211_vif *vif,
+                               struct ieee80211_sta *sta,
+                               struct sk_buff_head *skbs,
+                               bool txpending)
 {
         struct sk_buff *skb, *tmp;
         struct ieee80211_tx_info *info;
-        struct ieee80211_sub_if_data *sdata;
         unsigned long flags;
-        __le16 fc;
-
-        if (WARN_ON(skb_queue_empty(skbs)))
-                return true;
-
-        skb = skb_peek(skbs);
-        fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
 
         skb_queue_walk_safe(skbs, skb, tmp) {
                 int q = skb_get_queue_mapping(skb);
@@ -1242,37 +1233,72 @@ static bool __ieee80211_tx(struct ieee80211_local *local,
                 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
 
                 info = IEEE80211_SKB_CB(skb);
+                info->control.vif = vif;
+                info->control.sta = sta;
 
-                sdata = vif_to_sdata(info->control.vif);
+                __skb_unlink(skb, skbs);
+                drv_tx(local, skb);
+        }
 
-                switch (sdata->vif.type) {
-                case NL80211_IFTYPE_MONITOR:
-                        info->control.vif = NULL;
-                        break;
-                case NL80211_IFTYPE_AP_VLAN:
-                        info->control.vif = &container_of(sdata->bss,
-                                struct ieee80211_sub_if_data, u.ap)->vif;
-                        break;
-                default:
-                        /* keep */
-                        break;
-                }
+        return true;
+}
 
-                if (sta && sta->uploaded)
-                        info->control.sta = &sta->sta;
-                else
-                        info->control.sta = NULL;
+/*
+ * Returns false if the frame couldn't be transmitted but was queued instead.
+ */
+static bool __ieee80211_tx(struct ieee80211_local *local,
+                           struct sk_buff_head *skbs, int led_len,
+                           struct sta_info *sta, bool txpending)
+{
+        struct ieee80211_tx_info *info;
+        struct ieee80211_sub_if_data *sdata;
+        struct ieee80211_vif *vif;
+        struct ieee80211_sta *pubsta;
+        struct sk_buff *skb;
+        bool result = true;
+        __le16 fc;
 
-                __skb_unlink(skb, skbs);
-                drv_tx(local, skb);
+        if (WARN_ON(skb_queue_empty(skbs)))
+                return true;
+
+        skb = skb_peek(skbs);
+        fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
+        info = IEEE80211_SKB_CB(skb);
+        sdata = vif_to_sdata(info->control.vif);
+        if (sta && !sta->uploaded)
+                sta = NULL;
+
+        if (sta)
+                pubsta = &sta->sta;
+        else
+                pubsta = NULL;
+
+        switch (sdata->vif.type) {
+        case NL80211_IFTYPE_MONITOR:
+                sdata = NULL;
+                vif = NULL;
+                break;
+        case NL80211_IFTYPE_AP_VLAN:
+                sdata = container_of(sdata->bss,
+                                     struct ieee80211_sub_if_data, u.ap);
+                /* fall through */
+        default:
+                vif = &sdata->vif;
+                break;
         }
 
+        if (local->ops->tx_frags)
+                drv_tx_frags(local, vif, pubsta, skbs);
+        else
+                result = ieee80211_tx_frags(local, vif, pubsta, skbs,
+                                            txpending);
+
         ieee80211_tpt_led_trig_tx(local, fc, led_len);
         ieee80211_led_tx(local, 1);
 
         WARN_ON(!skb_queue_empty(skbs));
 
-        return true;
+        return result;
 }
 
 /*