mac80211: make noack test available

There's this internal wifi_wme_noack_test variable that
we use to set the QoS control if set. For one, it is
unlikely that it is set. Secondly, if set it needs to
influence the IEEE80211_TX_CTL_NO_ACK TX control flag,
and finally we should also be able to set it at all, so
make it available in debugfs.

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

4 files changed, 44 insertions, 2 deletions

diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c
index ac793201b701..e7682fe1c590 100644
--- a/net/mac80211/debugfs.c
+++ b/net/mac80211/debugfs.c
@@ -135,6 +135,42 @@ static const struct file_operations reset_ops = {
         .open = mac80211_open_file_generic,
 };
 
+static ssize_t noack_read(struct file *file, char __user *user_buf,
+                          size_t count, loff_t *ppos)
+{
+        struct ieee80211_local *local = file->private_data;
+        int res;
+        char buf[10];
+
+        res = scnprintf(buf, sizeof(buf), "%d\n", local->wifi_wme_noack_test);
+
+        return simple_read_from_buffer(user_buf, count, ppos, buf, res);
+}
+
+static ssize_t noack_write(struct file *file,
+                           const char __user *user_buf,
+                           size_t count, loff_t *ppos)
+{
+        struct ieee80211_local *local = file->private_data;
+        char buf[10];
+        size_t len;
+
+        len = min(count, sizeof(buf) - 1);
+        if (copy_from_user(buf, user_buf, len))
+                return -EFAULT;
+        buf[len] = '\0';
+
+        local->wifi_wme_noack_test = !!simple_strtoul(buf, NULL, 0);
+
+        return count;
+}
+
+static const struct file_operations noack_ops = {
+        .read = noack_read,
+        .write = noack_write,
+        .open = mac80211_open_file_generic
+};
+
 /* statistics stuff */
 
 #define DEBUGFS_STATS_FILE(name, buflen, fmt, value...)                 \
@@ -275,6 +311,7 @@ void debugfs_hw_add(struct ieee80211_local *local)
         DEBUGFS_ADD(wep_iv);
         DEBUGFS_ADD(tsf);
         DEBUGFS_ADD_MODE(reset, 0200);
+        DEBUGFS_ADD(noack);
 
         statsd = debugfs_create_dir("statistics", phyd);
         local->debugfs.statistics = statsd;
@@ -330,6 +367,7 @@ void debugfs_hw_del(struct ieee80211_local *local)
         DEBUGFS_DEL(wep_iv);
         DEBUGFS_DEL(tsf);
         DEBUGFS_DEL(reset);
+        DEBUGFS_DEL(noack);
 
         DEBUGFS_STATS_DEL(transmitted_fragment_count);
         DEBUGFS_STATS_DEL(multicast_transmitted_frame_count);
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 56a49ef446ca..9d1514727f6e 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -766,6 +766,7 @@ struct ieee80211_local {
                 struct dentry *wep_iv;
                 struct dentry *tsf;
                 struct dentry *reset;
+                struct dentry *noack;
                 struct dentry *statistics;
                 struct local_debugfsdentries_statsdentries {
                         struct dentry *transmitted_fragment_count;
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 5f9a8d7af83d..8f68bf9746d0 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -1087,7 +1087,10 @@ __ieee80211_tx_prepare(struct ieee80211_tx_data *tx,
                 info->flags |= IEEE80211_TX_CTL_NO_ACK;
         } else {
                 tx->flags |= IEEE80211_TX_UNICAST;
-                info->flags &= ~IEEE80211_TX_CTL_NO_ACK;
+                if (unlikely(local->wifi_wme_noack_test))
+                        info->flags |= IEEE80211_TX_CTL_NO_ACK;
+                else
+                        info->flags &= ~IEEE80211_TX_CTL_NO_ACK;
         }
 
         if (tx->flags & IEEE80211_TX_FRAGMENTED) {
diff --git a/net/mac80211/wme.c b/net/mac80211/wme.c
index 0b8ad1f4ecdd..45b74f38b867 100644
--- a/net/mac80211/wme.c
+++ b/net/mac80211/wme.c
@@ -133,7 +133,7 @@ u16 ieee80211_select_queue(struct net_device *dev, struct sk_buff *skb)
                 u8 *p = ieee80211_get_qos_ctl(hdr);
                 u8 ack_policy = 0;
                 tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK;
-                if (local->wifi_wme_noack_test)
+                if (unlikely(local->wifi_wme_noack_test))
                         ack_policy |= QOS_CONTROL_ACK_POLICY_NOACK <<
                                         QOS_CONTROL_ACK_POLICY_SHIFT;
                 /* qos header is 2 bytes, second reserved */