diff options
| author | Johannes Berg <johannes@sipsolutions.net> | 2008-05-12 20:48:31 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2008-05-12 20:48:31 -0700 |
| commit | f5184d267c1aedb9b7a8cc44e08ff6b8d382c3b5 (patch) | |
| tree | 5ccce7558f9e1e53e5b189d6e2fe62a667988ac8 /include/linux/netdevice.h | |
| parent | 8388e3da34edb141362bb42811ee487dfec15525 (diff) | |
net: Allow netdevices to specify needed head/tailroom
This patch adds needed_headroom/needed_tailroom members to struct
net_device and updates many places that allocate sbks to use them. Not
all of them can be converted though, and I'm sure I missed some (I
mostly grepped for LL_RESERVED_SPACE)
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
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. */ |