net-timestamp: no-payload option
authorWillem de Bruijn <willemb@google.com>
Fri, 30 Jan 2015 18:29:31 +0000 (13:29 -0500)
committerDavid S. Miller <davem@davemloft.net>
Tue, 3 Feb 2015 02:46:51 +0000 (18:46 -0800)
commit49ca0d8bfaf3bc46d5eef60ce67b00eb195bd392
treed2f55a32923f6d91fcb2e0d0e0b6d2d4eb6f9abd
parent9766e97af1b901ffbb36fcc648e50626d926bb24
net-timestamp: no-payload option

Add timestamping option SOF_TIMESTAMPING_OPT_TSONLY. For transmit
timestamps, this loops timestamps on top of empty packets.

Doing so reduces the pressure on SO_RCVBUF. Payload inspection and
cmsg reception (aside from timestamps) are no longer possible. This
works together with a follow on patch that allows administrators to
only allow tx timestamping if it does not loop payload or metadata.

Signed-off-by: Willem de Bruijn <willemb@google.com>
----

Changes (rfc -> v1)
  - add documentation
  - remove unnecessary skb->len test (thanks to Richard Cochran)
Signed-off-by: David S. Miller <davem@davemloft.net>
Documentation/networking/timestamping.txt
include/uapi/linux/net_tstamp.h
net/core/skbuff.c
net/ipv4/ip_sockglue.c
net/ipv6/datagram.c
net/rxrpc/ar-error.c