rt2x00: Add support for L2 padding during TX/RX

Some hardware require L2 padding between header and payload
because both must be aligned to a 4-byte boundary. This hardware
also is easier during the RX path since we no longer need to
move the entire payload but rather only the header to remove
the padding (mac80211 only wants the payload to be 4-byte aligned).

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 22 insertions, 5 deletions

diff --git a/drivers/net/wireless/rt2x00/rt2x00lib.h b/drivers/net/wireless/rt2x00/rt2x00lib.h
index af3c47bd43b..aa284e48d2c 100644
--- a/drivers/net/wireless/rt2x00/rt2x00lib.h
+++ b/drivers/net/wireless/rt2x00/rt2x00lib.h
@@ -113,6 +113,23 @@ void rt2x00queue_unmap_skb(struct rt2x00_dev *rt2x00dev, struct sk_buff *skb);
 void rt2x00queue_free_skb(struct rt2x00_dev *rt2x00dev, struct sk_buff *skb);
 
 /**
+ * rt2x00queue_payload_align - Align 802.11 payload to 4-byte boundary
+ * @skb: The skb to align
+ * @l2pad: Should L2 padding be used
+ * @header_length: Length of 802.11 header
+ *
+ * This function prepares the @skb to be send to the device or mac80211.
+ * If @l2pad is set to true padding will occur between the 802.11 header
+ * and payload. Otherwise the padding will be done in front of the 802.11
+ * header.
+ * When @l2pad is set the function will check for the &SKBDESC_L2_PADDED
+ * flag in &skb_frame_desc. If that flag is set, the padding is removed
+ * and the flag cleared. Otherwise the padding is added and the flag is set.
+ */
+void rt2x00queue_payload_align(struct sk_buff *skb,
+                               bool l2pad, unsigned int header_length);
+
+/**
  * rt2x00queue_write_tx_frame - Write TX frame to hardware
  * @queue: Queue over which the frame should be send
  * @skb: The skb to send
@@ -299,8 +316,8 @@ void rt2x00crypto_tx_copy_iv(struct sk_buff *skb,
                              struct txentry_desc *txdesc);
 void rt2x00crypto_tx_remove_iv(struct sk_buff *skb,
                                struct txentry_desc *txdesc);
-void rt2x00crypto_tx_insert_iv(struct sk_buff *skb);
-void rt2x00crypto_rx_insert_iv(struct sk_buff *skb, unsigned int align,
+void rt2x00crypto_tx_insert_iv(struct sk_buff *skb, unsigned int header_length);
+void rt2x00crypto_rx_insert_iv(struct sk_buff *skb, bool l2pad,
                                unsigned int header_length,
                                struct rxdone_entry_desc *rxdesc);
 #else
@@ -330,12 +347,12 @@ static inline void rt2x00crypto_tx_remove_iv(struct sk_buff *skb,
 {
 }
 
-static inline void rt2x00crypto_tx_insert_iv(struct sk_buff *skb)
+static inline void rt2x00crypto_tx_insert_iv(struct sk_buff *skb,
+                                             unsigned int header_length)
 {
 }
 
-static inline void rt2x00crypto_rx_insert_iv(struct sk_buff *skb,
-                                             unsigned int align,
+static inline void rt2x00crypto_rx_insert_iv(struct sk_buff *skb, bool l2pad,
                                              unsigned int header_length,
                                              struct rxdone_entry_desc *rxdesc)
 {