packet: add PACKET_RESERVE sockopt
Add new sockopt to reserve some headroom in the mmaped ring frames in
front of the packet payload. This can be used f.i. when the VLAN header
needs to be (re)constructed to avoid moving the entire payload.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/if_packet.h b/include/linux/if_packet.h
index a630295..18db066 100644
--- a/include/linux/if_packet.h
+++ b/include/linux/if_packet.h
@@ -45,6 +45,7 @@
#define PACKET_ORIGDEV 9
#define PACKET_VERSION 10
#define PACKET_HDRLEN 11
+#define PACKET_RESERVE 12
struct tpacket_stats
{