path: root/net/8021q/vlan.h
diff options
authorEric Dumazet <eric.dumazet@gmail.com>2009-10-26 18:40:35 -0700
committerDavid S. Miller <davem@davemloft.net>2009-10-27 01:02:33 -0700
commit05423b241311c9380b7280179295bac7794281b6 (patch)
tree8a84aca48cbc30b142bdf143dbf11fdbab9cad67 /net/8021q/vlan.h
parentcan: sja1000: fix bug using library functions for skb allocation (diff)
vlan: allow null VLAN ID to be used
We currently use a 16 bit field (vlan_tci) to store VLAN ID/PRIO on a skb. Null value is used as a special value, meaning vlan tagging not enabled. This forbids use of null vlan ID. As pointed by David, some drivers use the 3 high order bits (PRIO) As VLAN ID is 12 bits, we can use the remaining bit (CFI) as a flag, and allow null VLAN ID. In case future code really wants to use VLAN_CFI_MASK, we'll have to use a bit outside of vlan_tci. #define VLAN_PRIO_MASK 0xe000 /* Priority Code Point */ #define VLAN_PRIO_SHIFT 13 #define VLAN_CFI_MASK 0x1000 /* Canonical Format Indicator */ #define VLAN_TAG_PRESENT VLAN_CFI_MASK #define VLAN_VID_MASK 0x0fff /* VLAN Identifier */ Reported-by: Gertjan Hofman <gertjan_hofman@yahoo.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/8021q/vlan.h')
1 files changed, 1 insertions, 1 deletions
diff --git a/net/8021q/vlan.h b/net/8021q/vlan.h
index 82570bc2a180..4ade5edf1033 100644
--- a/net/8021q/vlan.h
+++ b/net/8021q/vlan.h
@@ -89,7 +89,7 @@ static inline u32 vlan_get_ingress_priority(struct net_device *dev,
struct vlan_dev_info *vip = vlan_dev_info(dev);
- return vip->ingress_priority_map[(vlan_tci >> 13) & 0x7];
+ return vip->ingress_priority_map[(vlan_tci >> VLAN_PRIO_SHIFT) & 0x7];