From a3bcc23e890a6d49d6763d9eb073d711de2e0469 Mon Sep 17 00:00:00 2001
From: Ben Greear <greearb@candelatech.com>
Date: Wed, 1 Jun 2011 06:49:10 +0000
Subject: af-packet: Add flag to distinguish VID 0 from no-vlan.
Currently, user-space cannot determine if a 0 tcp_vlan_tci
means there is no VLAN tag or the VLAN ID was zero.
Add flag to make this explicit. User-space can check for
TP_STATUS_VLAN_VALID || tp_vlan_tci > 0, which will be backwards
compatible. Older could would have just checked for tp_vlan_tci,
so it will work no worse than before.
Signed-off-by: Ben Greear <greearb@candelatech.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
include/linux/if_packet.h | 1 +
1 file changed, 1 insertion(+)
(limited to 'include/linux/if_packet.h')
diff --git a/include/linux/if_packet.h b/include/linux/if_packet.h
index 72bfa5a034dd..6d66ce1791a9 100644
--- a/include/linux/if_packet.h
+++ b/include/linux/if_packet.h
@@ -70,6 +70,7 @@ struct tpacket_auxdata {
#define TP_STATUS_COPY 0x2
#define TP_STATUS_LOSING 0x4
#define TP_STATUS_CSUMNOTREADY 0x8
+#define TP_STATUS_VLAN_VALID 0x10 /* auxdata has valid tp_vlan_tci */
/* Tx ring - header status */
#define TP_STATUS_AVAILABLE 0x0
--
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