mac80211: implement wifi TX status
Johannes Berg [Sun, 6 Nov 2011 13:13:34 +0000 (14:13 +0100)]
Implement the socket wifi TX status error
queue reflection in mac80211.

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

include/net/mac80211.h
net/mac80211/ieee80211_i.h
net/mac80211/main.c
net/mac80211/status.c
net/mac80211/tx.c

index b9b9c94..2714646 100644 (file)
@@ -518,7 +518,7 @@ struct ieee80211_tx_rate {
  * @flags: transmit info flags, defined above
  * @band: the band to transmit on (use for checking for races)
  * @antenna_sel_tx: antenna to use, 0 for automatic diversity
- * @pad: padding, ignore
+ * @ack_frame_id: internal frame ID for TX status, used internally
  * @control: union for control data
  * @status: union for status data
  * @driver_data: array of driver_data pointers
@@ -535,8 +535,7 @@ struct ieee80211_tx_info {
 
        u8 antenna_sel_tx;
 
-       /* 2 byte hole */
-       u8 pad[2];
+       u16 ack_frame_id;
 
        union {
                struct {
index 4bef6ec..76e656b 100644 (file)
@@ -24,6 +24,7 @@
 #include <linux/spinlock.h>
 #include <linux/etherdevice.h>
 #include <linux/leds.h>
+#include <linux/idr.h>
 #include <net/ieee80211_radiotap.h>
 #include <net/cfg80211.h>
 #include <net/mac80211.h>
@@ -1017,6 +1018,9 @@ struct ieee80211_local {
        u32 hw_roc_cookie;
        bool hw_roc_for_tx;
 
+       struct idr ack_status_frames;
+       spinlock_t ack_status_lock;
+
        /* dummy netdev for use w/ NAPI */
        struct net_device napi_dev;
 
index 8e9327b..e323d4e 100644 (file)
@@ -596,6 +596,8 @@ struct ieee80211_hw *ieee80211_alloc_hw(size_t priv_data_len,
                        WIPHY_FLAG_4ADDR_STATION |
                        WIPHY_FLAG_REPORTS_OBSS;
 
+       wiphy->features = NL80211_FEATURE_SK_TX_STATUS;
+
        if (!ops->set_key)
                wiphy->flags |= WIPHY_FLAG_IBSS_RSN;
 
@@ -669,6 +671,11 @@ struct ieee80211_hw *ieee80211_alloc_hw(size_t priv_data_len,
        INIT_WORK(&local->sched_scan_stopped_work,
                  ieee80211_sched_scan_stopped_work);
 
+       spin_lock_init(&local->ack_status_lock);
+       idr_init(&local->ack_status_frames);
+       /* preallocate at least one entry */
+       idr_pre_get(&local->ack_status_frames, GFP_KERNEL);
+
        sta_info_init(local);
 
        for (i = 0; i < IEEE80211_MAX_QUEUES; i++) {
@@ -1044,6 +1051,13 @@ void ieee80211_unregister_hw(struct ieee80211_hw *hw)
 }
 EXPORT_SYMBOL(ieee80211_unregister_hw);
 
+static int ieee80211_free_ack_frame(int id, void *p, void *data)
+{
+       WARN_ONCE(1, "Have pending ack frames!\n");
+       kfree_skb(p);
+       return 0;
+}
+
 void ieee80211_free_hw(struct ieee80211_hw *hw)
 {
        struct ieee80211_local *local = hw_to_local(hw);
@@ -1054,6 +1068,10 @@ void ieee80211_free_hw(struct ieee80211_hw *hw)
        if (local->wiphy_ciphers_allocated)
                kfree(local->hw.wiphy->cipher_suites);
 
+       idr_for_each(&local->ack_status_frames,
+                    ieee80211_free_ack_frame, NULL);
+       idr_destroy(&local->ack_status_frames);
+
        wiphy_free(local->hw.wiphy);
 }
 EXPORT_SYMBOL(ieee80211_free_hw);
index 94702f1..83b800d 100644 (file)
@@ -548,6 +548,24 @@ void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb)
                }
        }
 
+       if (unlikely(info->ack_frame_id)) {
+               struct sk_buff *ack_skb;
+               unsigned long flags;
+
+               spin_lock_irqsave(&local->ack_status_lock, flags);
+               ack_skb = idr_find(&local->ack_status_frames,
+                                  info->ack_frame_id);
+               if (ack_skb)
+                       idr_remove(&local->ack_status_frames,
+                                  info->ack_frame_id);
+               spin_unlock_irqrestore(&local->ack_status_lock, flags);
+
+               /* consumes ack_skb */
+               if (ack_skb)
+                       skb_complete_wifi_ack(ack_skb,
+                               info->flags & IEEE80211_TX_STAT_ACK);
+       }
+
        /* this was a transmitted frame, but now we want to reuse it */
        skb_orphan(skb);
 
@@ -621,6 +639,26 @@ EXPORT_SYMBOL(ieee80211_report_low_ack);
 
 void ieee80211_free_txskb(struct ieee80211_hw *hw, struct sk_buff *skb)
 {
+       struct ieee80211_local *local = hw_to_local(hw);
+       struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+
+       if (unlikely(info->ack_frame_id)) {
+               struct sk_buff *ack_skb;
+               unsigned long flags;
+
+               spin_lock_irqsave(&local->ack_status_lock, flags);
+               ack_skb = idr_find(&local->ack_status_frames,
+                                  info->ack_frame_id);
+               if (ack_skb)
+                       idr_remove(&local->ack_status_frames,
+                                  info->ack_frame_id);
+               spin_unlock_irqrestore(&local->ack_status_lock, flags);
+
+               /* consumes ack_skb */
+               if (ack_skb)
+                       dev_kfree_skb_any(ack_skb);
+       }
+
        dev_kfree_skb_any(skb);
 }
 EXPORT_SYMBOL(ieee80211_free_txskb);
index a543d26..ab6cb56 100644 (file)
@@ -1684,8 +1684,10 @@ netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb,
        int nh_pos, h_pos;
        struct sta_info *sta = NULL;
        bool wme_sta = false, authorized = false, tdls_auth = false;
-       struct sk_buff *tmp_skb;
        bool tdls_direct = false;
+       bool multicast;
+       u32 info_flags = 0;
+       u16 info_id = 0;
 
        if (unlikely(skb->len < ETH_HLEN)) {
                ret = NETDEV_TX_OK;
@@ -1872,7 +1874,8 @@ netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb,
         * if it is a multicast address (which can only happen
         * in AP mode)
         */
-       if (!is_multicast_ether_addr(hdr.addr1)) {
+       multicast = is_multicast_ether_addr(hdr.addr1);
+       if (!multicast) {
                rcu_read_lock();
                sta = sta_info_get(sdata, hdr.addr1);
                if (sta) {
@@ -1913,11 +1916,54 @@ netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb,
                goto fail;
        }
 
+       if (unlikely(!multicast && skb->sk &&
+                    skb_shinfo(skb)->tx_flags & SKBTX_WIFI_STATUS)) {
+               struct sk_buff *orig_skb = skb;
+
+               skb = skb_clone(skb, GFP_ATOMIC);
+               if (skb) {
+                       unsigned long flags;
+                       int id, r;
+
+                       spin_lock_irqsave(&local->ack_status_lock, flags);
+                       r = idr_get_new_above(&local->ack_status_frames,
+                                             orig_skb, 1, &id);
+                       if (r == -EAGAIN) {
+                               idr_pre_get(&local->ack_status_frames,
+                                           GFP_ATOMIC);
+                               r = idr_get_new_above(&local->ack_status_frames,
+                                                     orig_skb, 1, &id);
+                       }
+                       if (WARN_ON(!id) || id > 0xffff) {
+                               idr_remove(&local->ack_status_frames, id);
+                               r = -ERANGE;
+                       }
+                       spin_unlock_irqrestore(&local->ack_status_lock, flags);
+
+                       if (!r) {
+                               info_id = id;
+                               info_flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
+                       } else if (skb_shared(skb)) {
+                               kfree_skb(orig_skb);
+                       } else {
+                               kfree_skb(skb);
+                               skb = orig_skb;
+                       }
+               } else {
+                       /* couldn't clone -- lose tx status ... */
+                       skb = orig_skb;
+               }
+       }
+
        /*
         * If the skb is shared we need to obtain our own copy.
         */
        if (skb_shared(skb)) {
-               tmp_skb = skb;
+               struct sk_buff *tmp_skb = skb;
+
+               /* can't happen -- skb is a clone if info_id != 0 */
+               WARN_ON(info_id);
+
                skb = skb_clone(skb, GFP_ATOMIC);
                kfree_skb(tmp_skb);
 
@@ -2018,6 +2064,10 @@ netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb,
        memset(info, 0, sizeof(*info));
 
        dev->trans_start = jiffies;
+
+       info->flags = info_flags;
+       info->ack_frame_id = info_id;
+
        ieee80211_xmit(sdata, skb);
 
        return NETDEV_TX_OK;