diff options
| author | Gertjan van Wingerde <gwingerde@gmail.com> | 2009-12-04 23:46:54 +0100 |
|---|---|---|
| committer | John W. Linville <linville@tuxdriver.com> | 2009-12-14 14:22:31 -0500 |
| commit | d24deb2580823ab0b8425790c6f5d18e2ff749d8 (patch) | |
| tree | e19fa93ccf306ea54508492a141721a1e4cc3a30 | |
| parent | b2ec153a637409bd87952d44409905b7d98418b8 (diff) | |
mac80211: Add define for TX headroom reserved by mac80211 itself.
Add a definition of the amount of TX headroom reserved by mac80211 itself
for its own purposes. Also add BUILD_BUG_ON to validate the value.
This define can then be used by drivers to request additional TX headroom
in the most efficient manner.
Signed-off-by: Gertjan van Wingerde <gwingerde@gmail.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
| -rw-r--r-- | include/net/mac80211.h | 6 | ||||
| -rw-r--r-- | net/mac80211/main.c | 2 |
2 files changed, 8 insertions, 0 deletions
diff --git a/include/net/mac80211.h b/include/net/mac80211.h index 2aff4906b2ae..538d6b761887 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -1737,6 +1737,12 @@ static inline void ieee80211_rx_ni(struct ieee80211_hw *hw, local_bh_enable(); } +/* + * The TX headroom reserved by mac80211 for its own tx_status functions. + * This is enough for the radiotap header. + */ +#define IEEE80211_TX_STATUS_HEADROOM 13 + /** * ieee80211_tx_status - transmit status callback * diff --git a/net/mac80211/main.c b/net/mac80211/main.c index 8116d1a96a4a..0d2d94881f1f 100644 --- a/net/mac80211/main.c +++ b/net/mac80211/main.c @@ -515,6 +515,8 @@ int ieee80211_register_hw(struct ieee80211_hw *hw) * and we need some headroom for passing the frame to monitor * interfaces, but never both at the same time. */ + BUILD_BUG_ON(IEEE80211_TX_STATUS_HEADROOM != + sizeof(struct ieee80211_tx_status_rtap_hdr)); local->tx_headroom = max_t(unsigned int , local->hw.extra_tx_headroom, sizeof(struct ieee80211_tx_status_rtap_hdr)); |