b43: Rewrite TX bounce buffer handling

Do not mess with the original skb, but allocate an independent bouncebuffer.
This protects against bad interference with mac80211's assumptions about
the skb (which already caused bugs).

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 19 insertions, 0 deletions

diff --git a/drivers/net/wireless/b43/xmit.h b/drivers/net/wireless/b43/xmit.h
index 3530de871873..d23ff9fe0c9e 100644
--- a/drivers/net/wireless/b43/xmit.h
+++ b/drivers/net/wireless/b43/xmit.h
@@ -2,6 +2,8 @@
 #define B43_XMIT_H_
 
 #include "main.h"
+#include <net/mac80211.h>
+
 
 #define _b43_declare_plcp_hdr(size) \
         struct b43_plcp_hdr##size {             \
@@ -332,4 +334,21 @@ static inline u8 b43_kidx_to_raw(struct b43_wldev *dev, u8 firmware_kidx)
         return raw_kidx;
 }
 
+/* struct b43_private_tx_info - TX info private to b43.
+ * The structure is placed in (struct ieee80211_tx_info *)->rate_driver_data
+ *
+ * @bouncebuffer: DMA Bouncebuffer (if used)
+ */
+struct b43_private_tx_info {
+        void *bouncebuffer;
+};
+
+static inline struct b43_private_tx_info *
+b43_get_priv_tx_info(struct ieee80211_tx_info *info)
+{
+        BUILD_BUG_ON(sizeof(struct b43_private_tx_info) >
+                     sizeof(info->rate_driver_data));
+        return (struct b43_private_tx_info *)info->rate_driver_data;
+}
+
 #endif /* B43_XMIT_H_ */