mac80211: push rx status into skb->cb

Within mac80211, we often need to copy the rx status into
skb->cb. This is wasteful, as drivers could be building it
in there to start with. This patch changes the API so that
drivers are expected to pass the RX status in skb->cb, now
accessible as IEEE80211_SKB_RXCB(skb). It also updates all
drivers to pass the rx status in there, but only by making
them memcpy() it into place before the call to the receive
function (ieee80211_rx(_irqsafe)). Each driver can now be
optimised on its own schedule.

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

2 files changed, 4 insertions, 2 deletions

diff --git a/drivers/net/wireless/rtl818x/rtl8180_dev.c b/drivers/net/wireless/rtl818x/rtl8180_dev.c
index 7e65d7c31802..47521c5b6f91 100644
--- a/drivers/net/wireless/rtl818x/rtl8180_dev.c
+++ b/drivers/net/wireless/rtl818x/rtl8180_dev.c
@@ -143,7 +143,8 @@ static void rtl8180_handle_rx(struct ieee80211_hw *dev)
                         if (flags & RTL818X_RX_DESC_FLAG_CRC32_ERR)
                                 rx_status.flag |= RX_FLAG_FAILED_FCS_CRC;
 
-                        ieee80211_rx_irqsafe(dev, skb, &rx_status);
+                        memcpy(IEEE80211_SKB_RXCB(skb), &rx_status, sizeof(rx_status));
+                        ieee80211_rx_irqsafe(dev, skb);
 
                         skb = new_skb;
                         priv->rx_buf[priv->rx_idx] = skb;
diff --git a/drivers/net/wireless/rtl818x/rtl8187_dev.c b/drivers/net/wireless/rtl818x/rtl8187_dev.c
index 294250e294dd..c9b9dbe584c6 100644
--- a/drivers/net/wireless/rtl818x/rtl8187_dev.c
+++ b/drivers/net/wireless/rtl818x/rtl8187_dev.c
@@ -380,7 +380,8 @@ static void rtl8187_rx_cb(struct urb *urb)
         rx_status.flag |= RX_FLAG_TSFT;
         if (flags & RTL818X_RX_DESC_FLAG_CRC32_ERR)
                 rx_status.flag |= RX_FLAG_FAILED_FCS_CRC;
-        ieee80211_rx_irqsafe(dev, skb, &rx_status);
+        memcpy(IEEE80211_SKB_RXCB(skb), &rx_status, sizeof(rx_status));
+        ieee80211_rx_irqsafe(dev, skb);
 
         skb = dev_alloc_skb(RTL8187_MAX_RX);
         if (unlikely(!skb)) {