6 files changed, 164 insertions, 3 deletions

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 972109f06a70..9259e97864d7 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1586,6 +1586,20 @@ enum ieee80211_ampdu_mlme_action {
 };
 
 /**
+ * enum ieee80211_tx_sync_type - TX sync type
+ * @IEEE80211_TX_SYNC_AUTH: sync TX for authentication
+ *      (and possibly also before direct probe)
+ * @IEEE80211_TX_SYNC_ASSOC: sync TX for association
+ * @IEEE80211_TX_SYNC_ACTION: sync TX for action frame
+ *      (not implemented yet)
+ */
+enum ieee80211_tx_sync_type {
+        IEEE80211_TX_SYNC_AUTH,
+        IEEE80211_TX_SYNC_ASSOC,
+        IEEE80211_TX_SYNC_ACTION,
+};
+
+/**
  * struct ieee80211_ops - callbacks from mac80211 to the driver
  *
  * This structure contains various callbacks that the driver may
@@ -1674,6 +1688,26 @@ enum ieee80211_ampdu_mlme_action {
  *      of the bss parameters has changed when a call is made. The callback
  *      can sleep.
  *
+ * @tx_sync: Called before a frame is sent to an AP/GO. In the GO case, the
+ *      driver should sync with the GO's powersaving so the device doesn't
+ *      transmit the frame while the GO is asleep. In the regular AP case
+ *      it may be used by drivers for devices implementing other restrictions
+ *      on talking to APs, e.g. due to regulatory enforcement or just HW
+ *      restrictions.
+ *      This function is called for every authentication, association and
+ *      action frame separately since applications might attempt to auth
+ *      with multiple APs before chosing one to associate to. If it returns
+ *      an error, the corresponding authentication, association or frame
+ *      transmission is aborted and reported as having failed. It is always
+ *      called after tuning to the correct channel.
+ *      The callback might be called multiple times before @finish_tx_sync
+ *      (but @finish_tx_sync will be called once for each) but in practice
+ *      this is unlikely to happen. It can also refuse in that case if the
+ *      driver cannot handle that situation.
+ *      This callback can sleep.
+ * @finish_tx_sync: Called as a counterpart to @tx_sync, unless that returned
+ *      an error. This callback can sleep.
+ *
  * @prepare_multicast: Prepare for multicast filter configuration.
  *      This callback is optional, and its return value is passed
  *      to configure_filter(). This callback must be atomic.
@@ -1901,6 +1935,14 @@ struct ieee80211_ops {
                                  struct ieee80211_vif *vif,
                                  struct ieee80211_bss_conf *info,
                                  u32 changed);
+
+        int (*tx_sync)(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
+                       const u8 *bssid, enum ieee80211_tx_sync_type type);
+        void (*finish_tx_sync)(struct ieee80211_hw *hw,
+                               struct ieee80211_vif *vif,
+                               const u8 *bssid,
+                               enum ieee80211_tx_sync_type type);
+
         u64 (*prepare_multicast)(struct ieee80211_hw *hw,
                                  struct netdev_hw_addr_list *mc_list);
         void (*configure_filter)(struct ieee80211_hw *hw,
diff --git a/net/mac80211/driver-ops.h b/net/mac80211/driver-ops.h
index b2d6bba44054..1425380983f7 100644
--- a/net/mac80211/driver-ops.h
+++ b/net/mac80211/driver-ops.h
@@ -130,6 +130,37 @@ static inline void drv_bss_info_changed(struct ieee80211_local *local,
         trace_drv_return_void(local);
 }
 
+static inline int drv_tx_sync(struct ieee80211_local *local,
+                              struct ieee80211_sub_if_data *sdata,
+                              const u8 *bssid,
+                              enum ieee80211_tx_sync_type type)
+{
+        int ret = 0;
+
+        might_sleep();
+
+        trace_drv_tx_sync(local, sdata, bssid, type);
+        if (local->ops->tx_sync)
+                ret = local->ops->tx_sync(&local->hw, &sdata->vif,
+                                          bssid, type);
+        trace_drv_return_int(local, ret);
+        return ret;
+}
+
+static inline void drv_finish_tx_sync(struct ieee80211_local *local,
+                                      struct ieee80211_sub_if_data *sdata,
+                                      const u8 *bssid,
+                                      enum ieee80211_tx_sync_type type)
+{
+        might_sleep();
+
+        trace_drv_finish_tx_sync(local, sdata, bssid, type);
+        if (local->ops->finish_tx_sync)
+                local->ops->finish_tx_sync(&local->hw, &sdata->vif,
+                                           bssid, type);
+        trace_drv_return_void(local);
+}
+
 static inline u64 drv_prepare_multicast(struct ieee80211_local *local,
                                         struct netdev_hw_addr_list *mc_list)
 {
diff --git a/net/mac80211/driver-trace.h b/net/mac80211/driver-trace.h
index 4470f6e8b845..f47b00dc7afd 100644
--- a/net/mac80211/driver-trace.h
+++ b/net/mac80211/driver-trace.h
@@ -319,6 +319,49 @@ TRACE_EVENT(drv_bss_info_changed,
         )
 );
 
+DECLARE_EVENT_CLASS(tx_sync_evt,
+        TP_PROTO(struct ieee80211_local *local,
+                 struct ieee80211_sub_if_data *sdata,
+                 const u8 *bssid,
+                 enum ieee80211_tx_sync_type type),
+        TP_ARGS(local, sdata, bssid, type),
+
+        TP_STRUCT__entry(
+                LOCAL_ENTRY
+                VIF_ENTRY
+                __array(char, bssid, ETH_ALEN)
+                __field(u32, sync_type)
+        ),
+
+        TP_fast_assign(
+                LOCAL_ASSIGN;
+                VIF_ASSIGN;
+                memcpy(__entry->bssid, bssid, ETH_ALEN);
+                __entry->sync_type = type;
+        ),
+
+        TP_printk(
+                LOCAL_PR_FMT  VIF_PR_FMT " bssid:%pM type:%d",
+                LOCAL_PR_ARG, VIF_PR_ARG, __entry->bssid, __entry->sync_type
+        )
+);
+
+DEFINE_EVENT(tx_sync_evt, drv_tx_sync,
+        TP_PROTO(struct ieee80211_local *local,
+                 struct ieee80211_sub_if_data *sdata,
+                 const u8 *bssid,
+                 enum ieee80211_tx_sync_type type),
+        TP_ARGS(local, sdata, bssid, type)
+);
+
+DEFINE_EVENT(tx_sync_evt, drv_finish_tx_sync,
+        TP_PROTO(struct ieee80211_local *local,
+                 struct ieee80211_sub_if_data *sdata,
+                 const u8 *bssid,
+                 enum ieee80211_tx_sync_type type),
+        TP_ARGS(local, sdata, bssid, type)
+);
+
 TRACE_EVENT(drv_prepare_multicast,
         TP_PROTO(struct ieee80211_local *local, int mc_count),
 
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index eb9d4826f775..400c09bea639 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -323,6 +323,7 @@ struct ieee80211_work {
                         u8 key[WLAN_KEY_LEN_WEP104];
                         u8 key_len, key_idx;
                         bool privacy;
+                        bool synced;
                 } probe_auth;
                 struct {
                         struct cfg80211_bss *bss;
@@ -336,6 +337,7 @@ struct ieee80211_work {
                         u8 ssid_len;
                         u8 supp_rates_len;
                         bool wmm_used, use_11n, uapsd_used;
+                        bool synced;
                 } assoc;
                 struct {
                         u32 duration;
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index fee706d39fc2..d6470c7fd6ce 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -2335,14 +2335,16 @@ static enum work_done_result
 ieee80211_probe_auth_done(struct ieee80211_work *wk,
                           struct sk_buff *skb)
 {
+        struct ieee80211_local *local = wk->sdata->local;
+
         if (!skb) {
                 cfg80211_send_auth_timeout(wk->sdata->dev, wk->filter_ta);
-                return WORK_DONE_DESTROY;
+                goto destroy;
         }
 
         if (wk->type == IEEE80211_WORK_AUTH) {
                 cfg80211_send_rx_auth(wk->sdata->dev, skb->data, skb->len);
-                return WORK_DONE_DESTROY;
+                goto destroy;
         }
 
         mutex_lock(&wk->sdata->u.mgd.mtx);
@@ -2352,6 +2354,12 @@ ieee80211_probe_auth_done(struct ieee80211_work *wk,
         wk->type = IEEE80211_WORK_AUTH;
         wk->probe_auth.tries = 0;
         return WORK_DONE_REQUEUE;
+ destroy:
+        if (wk->probe_auth.synced)
+                drv_finish_tx_sync(local, wk->sdata, wk->filter_ta,
+                                   IEEE80211_TX_SYNC_AUTH);
+
+        return WORK_DONE_DESTROY;
 }
 
 int ieee80211_mgd_auth(struct ieee80211_sub_if_data *sdata,
@@ -2424,6 +2432,7 @@ int ieee80211_mgd_auth(struct ieee80211_sub_if_data *sdata,
 static enum work_done_result ieee80211_assoc_done(struct ieee80211_work *wk,
                                                   struct sk_buff *skb)
 {
+        struct ieee80211_local *local = wk->sdata->local;
         struct ieee80211_mgmt *mgmt;
         struct ieee80211_rx_status *rx_status;
         struct ieee802_11_elems elems;
@@ -2431,7 +2440,7 @@ static enum work_done_result ieee80211_assoc_done(struct ieee80211_work *wk,
 
         if (!skb) {
                 cfg80211_send_assoc_timeout(wk->sdata->dev, wk->filter_ta);
-                return WORK_DONE_DESTROY;
+                goto destroy;
         }
 
         if (wk->type == IEEE80211_WORK_ASSOC_BEACON_WAIT) {
@@ -2451,6 +2460,10 @@ static enum work_done_result ieee80211_assoc_done(struct ieee80211_work *wk,
         status = le16_to_cpu(mgmt->u.assoc_resp.status_code);
 
         if (status == WLAN_STATUS_SUCCESS) {
+                if (wk->assoc.synced)
+                        drv_finish_tx_sync(local, wk->sdata, wk->filter_ta,
+                                           IEEE80211_TX_SYNC_ASSOC);
+
                 mutex_lock(&wk->sdata->u.mgd.mtx);
                 if (!ieee80211_assoc_success(wk, mgmt, skb->len)) {
                         mutex_unlock(&wk->sdata->u.mgd.mtx);
@@ -2464,6 +2477,11 @@ static enum work_done_result ieee80211_assoc_done(struct ieee80211_work *wk,
         }
 
         cfg80211_send_rx_assoc(wk->sdata->dev, skb->data, skb->len);
+ destroy:
+        if (wk->assoc.synced)
+                drv_finish_tx_sync(local, wk->sdata, wk->filter_ta,
+                                   IEEE80211_TX_SYNC_ASSOC);
+
         return WORK_DONE_DESTROY;
 }
 
diff --git a/net/mac80211/work.c b/net/mac80211/work.c
index f0c74a1a9a02..380b9a7462b6 100644
--- a/net/mac80211/work.c
+++ b/net/mac80211/work.c
@@ -25,6 +25,7 @@
 
 #include "ieee80211_i.h"
 #include "rate.h"
+#include "driver-ops.h"
 
 #define IEEE80211_AUTH_TIMEOUT (HZ / 5)
 #define IEEE80211_AUTH_MAX_TRIES 3
@@ -427,6 +428,14 @@ ieee80211_direct_probe(struct ieee80211_work *wk)
         struct ieee80211_sub_if_data *sdata = wk->sdata;
         struct ieee80211_local *local = sdata->local;
 
+        if (!wk->probe_auth.synced) {
+                int ret = drv_tx_sync(local, sdata, wk->filter_ta,
+                                      IEEE80211_TX_SYNC_AUTH);
+                if (ret)
+                        return WORK_ACT_TIMEOUT;
+        }
+        wk->probe_auth.synced = true;
+
         wk->probe_auth.tries++;
         if (wk->probe_auth.tries > IEEE80211_AUTH_MAX_TRIES) {
                 printk(KERN_DEBUG "%s: direct probe to %pM timed out\n",
@@ -466,6 +475,14 @@ ieee80211_authenticate(struct ieee80211_work *wk)
         struct ieee80211_sub_if_data *sdata = wk->sdata;
         struct ieee80211_local *local = sdata->local;
 
+        if (!wk->probe_auth.synced) {
+                int ret = drv_tx_sync(local, sdata, wk->filter_ta,
+                                      IEEE80211_TX_SYNC_AUTH);
+                if (ret)
+                        return WORK_ACT_TIMEOUT;
+        }
+        wk->probe_auth.synced = true;
+
         wk->probe_auth.tries++;
         if (wk->probe_auth.tries > IEEE80211_AUTH_MAX_TRIES) {
                 printk(KERN_DEBUG "%s: authentication with %pM"
@@ -499,6 +516,14 @@ ieee80211_associate(struct ieee80211_work *wk)
         struct ieee80211_sub_if_data *sdata = wk->sdata;
         struct ieee80211_local *local = sdata->local;
 
+        if (!wk->assoc.synced) {
+                int ret = drv_tx_sync(local, sdata, wk->filter_ta,
+                                      IEEE80211_TX_SYNC_ASSOC);
+                if (ret)
+                        return WORK_ACT_TIMEOUT;
+        }
+        wk->assoc.synced = true;
+
         wk->assoc.tries++;
         if (wk->assoc.tries > IEEE80211_ASSOC_MAX_TRIES) {
                 printk(KERN_DEBUG "%s: association with %pM"