diff options
Diffstat (limited to 'include/linux/netdevice.h')
| -rw-r--r-- | include/linux/netdevice.h | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index a3fb57fde623..b11e6e19e96c 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -246,11 +246,16 @@ struct hh_cache * * We could use other alignment values, but we must maintain the * relationship HH alignment <= LL alignment. + * + * LL_ALLOCATED_SPACE also takes into account the tailroom the device + * may need. */ #define LL_RESERVED_SPACE(dev) \ - (((dev)->hard_header_len&~(HH_DATA_MOD - 1)) + HH_DATA_MOD) + ((((dev)->hard_header_len+(dev)->needed_headroom)&~(HH_DATA_MOD - 1)) + HH_DATA_MOD) #define LL_RESERVED_SPACE_EXTRA(dev,extra) \ - ((((dev)->hard_header_len+extra)&~(HH_DATA_MOD - 1)) + HH_DATA_MOD) + ((((dev)->hard_header_len+(dev)->needed_headroom+(extra))&~(HH_DATA_MOD - 1)) + HH_DATA_MOD) +#define LL_ALLOCATED_SPACE(dev) \ + ((((dev)->hard_header_len+(dev)->needed_headroom+(dev)->needed_tailroom)&~(HH_DATA_MOD - 1)) + HH_DATA_MOD) struct header_ops { int (*create) (struct sk_buff *skb, struct net_device *dev, @@ -569,6 +574,13 @@ struct net_device unsigned short type; /* interface hardware type */ unsigned short hard_header_len; /* hardware hdr length */ + /* extra head- and tailroom the hardware may need, but not in all cases + * can this be guaranteed, especially tailroom. Some cases also use + * LL_MAX_HEADER instead to allocate the skb. + */ + unsigned short needed_headroom; + unsigned short needed_tailroom; + struct net_device *master; /* Pointer to master device of a group, * which this device is member of. */ |