packet: doc: add documentation for VLAN TPID delivery
Introduce TP_STATUS_VLAN_TPID_VALID bit into the documentation.
Signed-off-by: Atzm Watanabe <atzm@stratosphere.co.jp>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/Documentation/networking/packet_mmap.txt b/Documentation/networking/packet_mmap.txt
index 4288ffa..723bf3d 100644
--- a/Documentation/networking/packet_mmap.txt
+++ b/Documentation/networking/packet_mmap.txt
@@ -517,8 +517,6 @@
TPACKET_V1:
- Default if not otherwise specified by setsockopt(2)
- RX_RING, TX_RING available
- - VLAN metadata information available for packets
- (TP_STATUS_VLAN_VALID)
TPACKET_V1 --> TPACKET_V2:
- Made 64 bit clean due to unsigned long usage in TPACKET_V1
@@ -526,6 +524,13 @@
userspace and the like
- Timestamp resolution in nanoseconds instead of microseconds
- RX_RING, TX_RING available
+ - VLAN metadata information available for packets
+ (TP_STATUS_VLAN_VALID, TP_STATUS_VLAN_TPID_VALID),
+ in the tpacket2_hdr structure:
+ - TP_STATUS_VLAN_VALID bit being set into the tp_status field indicates
+ that the tp_vlan_tci field has valid VLAN TCI value
+ - TP_STATUS_VLAN_TPID_VALID bit being set into the tp_status field
+ indicates that the tp_vlan_tpid field has valid VLAN TPID value
- How to switch to TPACKET_V2:
1. Replace struct tpacket_hdr by struct tpacket2_hdr
2. Query header len and save