[net-next 01/16] net: Support RXFCS feature flag.
From: Jeff Kirsher <hidden>
Date: 2012-02-24 10:13:14
Subsystem:
documentation, networking drivers, networking [general], the rest · Maintainers:
Jonathan Corbet, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Ben Greear <redacted> When set on hardware that supports the feature, this causes the Ethernet FCS to be appended to the end of the skb. Useful for sniffing packets. Signed-off-by: Ben Greear <redacted> Tested-by: Aaron Brown <redacted> Signed-off-by: Jeff Kirsher <redacted> --- Documentation/networking/netdev-features.txt | 6 ++++++ include/linux/netdev_features.h | 2 ++ net/core/ethtool.c | 1 + 3 files changed, 9 insertions(+), 0 deletions(-)
diff --git a/Documentation/networking/netdev-features.txt b/Documentation/networking/netdev-features.txt
index 4b1c0dc..7d27812 100644
--- a/Documentation/networking/netdev-features.txt
+++ b/Documentation/networking/netdev-features.txt@@ -152,3 +152,9 @@ NETIF_F_VLAN_CHALLENGED should be set for devices which can't cope with VLAN headers. Some drivers set this because the cards can't handle the bigger MTU. [FIXME: Those cases could be fixed in VLAN code by allowing only reduced-MTU VLANs. This may be not useful, though.] + +* rx-fcs + +This requests that the NIC append the Ethernet Frame Checksum (FCS) +to the end of the skb data. This allows sniffers and other tools to +read the CRC recorded by the NIC on receipt of the packet.
diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h
index 77f5202..d133186 100644
--- a/include/linux/netdev_features.h
+++ b/include/linux/netdev_features.h@@ -54,6 +54,7 @@ enum { NETIF_F_RXCSUM_BIT, /* Receive checksumming offload */ NETIF_F_NOCACHE_COPY_BIT, /* Use no-cache copyfromuser */ NETIF_F_LOOPBACK_BIT, /* Enable loopback */ + NETIF_F_RXFCS_BIT, /* Append FCS to skb pkt data */ /* * Add your fresh new feature above and remember to update
@@ -98,6 +99,7 @@ enum { #define NETIF_F_TSO __NETIF_F(TSO) #define NETIF_F_UFO __NETIF_F(UFO) #define NETIF_F_VLAN_CHALLENGED __NETIF_F(VLAN_CHALLENGED) +#define NETIF_F_RXFCS __NETIF_F(RXFCS) /* Features valid for ethtool to change */ /* = all defined minus driver/device-class-related */
diff --git a/net/core/ethtool.c b/net/core/ethtool.c
index 3f79db1..0801619 100644
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c@@ -73,6 +73,7 @@ static const char netdev_features_strings[NETDEV_FEATURE_COUNT][ETH_GSTRING_LEN] [NETIF_F_RXCSUM_BIT] = "rx-checksum", [NETIF_F_NOCACHE_COPY_BIT] = "tx-nocache-copy", [NETIF_F_LOOPBACK_BIT] = "loopback", + [NETIF_F_RXFCS_BIT] = "rx-fcs", }; static int ethtool_get_features(struct net_device *dev, void __user *useraddr)
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1.7.7.6