[RFC] [NET] restructure LL_MAX_HEADER code, increase headroom for 802.11
From: Johannes Berg <johannes@sipsolutions.net>
Date: 2008-05-04 18:44:10
This adds new default headroom for 802.11 and restructures the defines there to be more readable using #elif. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> --- include/linux/netdevice.h | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-)
--- everything.orig/include/linux/netdevice.h 2008-05-04 13:21:27.000000000 +0200
+++ everything/include/linux/netdevice.h 2008-05-04 13:22:34.000000000 +0200@@ -91,16 +91,26 @@ struct wireless_dev; /* * Compute the worst case header length according to the protocols * used. + * + * These must be ordered by decreasing size for obvious reasons. */ -#if !defined(CONFIG_AX25) && !defined(CONFIG_AX25_MODULE) && !defined(CONFIG_TR) -#define LL_MAX_HEADER 32 -#else #if defined(CONFIG_AX25) || defined(CONFIG_AX25_MODULE) #define LL_MAX_HEADER 96 -#else +#elif defined(MAC80211_MESH) +/* 802.11 (see below) plus 6-byte mesh header */ +#define LL_MAX_HEADER 54 +#elif defined(CONFIG_MAC80211) || defined(CONFIG_MAC80211_module) +/* + * ctl (2), seq (2), addr1 (6), addr2 (6), addr3 (6), + * seq (2), addr4 (2), qos (2), extended IV (8), + * rfc1042/bridge tunnel (8) + */ #define LL_MAX_HEADER 48 -#endif +#elif defined(CONFIG_TR) +#define LL_MAX_HEADER 48 +#else +#define LL_MAX_HEADER 32 #endif #if !defined(CONFIG_NET_IPIP) && !defined(CONFIG_NET_IPIP_MODULE) && \