mac80211: Send the management frame at requested rate

Whenever the scan request or tx_mgmt is requesting not to
use CCK rate for managemet frames through
NL80211_ATTR_TX_NO_CCK_RATE attribute, then mac80211 should
select appropriate least non-CCK rate. This could help to
send P2P probes and P2P action frames at non 11b rates
without diabling 11b rates globally.

Cc: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

7 files changed, 42 insertions, 7 deletions

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 9cba0104e291..56c35041ba97 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -1897,6 +1897,9 @@ static int ieee80211_mgmt_tx(struct wiphy *wiphy, struct net_device *dev,
                 flags |= IEEE80211_TX_CTL_TX_OFFCHAN;
         }
 
+        if (no_cck)
+                flags |= IEEE80211_TX_CTL_NO_CCK_RATE;
+
         if (is_offchan && !offchan)
                 return -EBUSY;
 
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 21186e280ceb..4822d69930e2 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -1324,7 +1324,7 @@ struct sk_buff *ieee80211_build_probe_req(struct ieee80211_sub_if_data *sdata,
 void ieee80211_send_probe_req(struct ieee80211_sub_if_data *sdata, u8 *dst,
                               const u8 *ssid, size_t ssid_len,
                               const u8 *ie, size_t ie_len,
-                              u32 ratemask, bool directed);
+                              u32 ratemask, bool directed, bool no_cck);
 
 void ieee80211_sta_def_wmm_params(struct ieee80211_sub_if_data *sdata,
                                   const size_t supp_rates_len,
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 1a59fb6630d4..cc80d320c922 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -1239,7 +1239,7 @@ static void ieee80211_mgd_probe_ap_send(struct ieee80211_sub_if_data *sdata)
         } else {
                 ssid = ieee80211_bss_get_ie(ifmgd->associated, WLAN_EID_SSID);
                 ieee80211_send_probe_req(sdata, dst, ssid + 2, ssid[1], NULL, 0,
-                                         (u32) -1, true);
+                                         (u32) -1, true, false);
         }
 
         ifmgd->probe_send_count++;
diff --git a/net/mac80211/rate.c b/net/mac80211/rate.c
index 3d5a2cb835c4..f61244c0e0a2 100644
--- a/net/mac80211/rate.c
+++ b/net/mac80211/rate.c
@@ -233,6 +233,27 @@ static void rc_send_low_broadcast(s8 *idx, u32 basic_rates,
         /* could not find a basic rate; use original selection */
 }
 
+static inline s8
+rate_lowest_non_cck_index(struct ieee80211_supported_band *sband,
+                          struct ieee80211_sta *sta)
+{
+        int i;
+
+        for (i = 0; i < sband->n_bitrates; i++) {
+                struct ieee80211_rate *srate = &sband->bitrates[i];
+                if ((srate->bitrate == 10) || (srate->bitrate == 20) ||
+                    (srate->bitrate == 55) || (srate->bitrate == 110))
+                        continue;
+
+                if (rate_supported(sta, sband->band, i))
+                        return i;
+        }
+
+        /* No matching rate found */
+        return 0;
+}
+
+
 bool rate_control_send_low(struct ieee80211_sta *sta,
                            void *priv_sta,
                            struct ieee80211_tx_rate_control *txrc)
@@ -242,7 +263,13 @@ bool rate_control_send_low(struct ieee80211_sta *sta,
         int mcast_rate;
 
         if (!sta || !priv_sta || rc_no_data_or_no_ack(txrc)) {
-                info->control.rates[0].idx = rate_lowest_index(txrc->sband, sta);
+                if ((sband->band != IEEE80211_BAND_2GHZ) ||
+                    !(info->flags & IEEE80211_TX_CTL_NO_CCK_RATE))
+                        info->control.rates[0].idx =
+                                rate_lowest_index(txrc->sband, sta);
+                else
+                        info->control.rates[0].idx =
+                                rate_lowest_non_cck_index(txrc->sband, sta);
                 info->control.rates[0].count =
                         (info->flags & IEEE80211_TX_CTL_NO_ACK) ?
                         1 : txrc->hw->max_rate_tries;
diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index 6f09eca01112..830e60f65779 100644
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -660,7 +660,8 @@ static void ieee80211_scan_state_send_probe(struct ieee80211_local *local,
                         local->scan_req->ssids[i].ssid,
                         local->scan_req->ssids[i].ssid_len,
                         local->scan_req->ie, local->scan_req->ie_len,
-                        local->scan_req->rates[band], false);
+                        local->scan_req->rates[band], false,
+                        local->scan_req->no_cck);
 
         /*
          * After sending probe requests, wait for probe responses
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 4b1466d5b6a1..ead345db7127 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -899,14 +899,18 @@ struct sk_buff *ieee80211_build_probe_req(struct ieee80211_sub_if_data *sdata,
 void ieee80211_send_probe_req(struct ieee80211_sub_if_data *sdata, u8 *dst,
                               const u8 *ssid, size_t ssid_len,
                               const u8 *ie, size_t ie_len,
-                              u32 ratemask, bool directed)
+                              u32 ratemask, bool directed, bool no_cck)
 {
         struct sk_buff *skb;
 
         skb = ieee80211_build_probe_req(sdata, dst, ratemask, ssid, ssid_len,
                                         ie, ie_len, directed);
-        if (skb)
+        if (skb) {
+                if (no_cck)
+                        IEEE80211_SKB_CB(skb)->flags |=
+                                IEEE80211_TX_CTL_NO_CCK_RATE;
                 ieee80211_tx_skb(sdata, skb);
+        }
 }
 
 u32 ieee80211_sta_get_rates(struct ieee80211_local *local,
diff --git a/net/mac80211/work.c b/net/mac80211/work.c
index bac34394c05e..af374fab1a12 100644
--- a/net/mac80211/work.c
+++ b/net/mac80211/work.c
@@ -458,7 +458,7 @@ ieee80211_direct_probe(struct ieee80211_work *wk)
          */
         ieee80211_send_probe_req(sdata, NULL, wk->probe_auth.ssid,
                                  wk->probe_auth.ssid_len, NULL, 0,
-                                 (u32) -1, true);
+                                 (u32) -1, true, false);
 
         wk->timeout = jiffies + IEEE80211_AUTH_TIMEOUT;
         run_again(local, wk->timeout);