diff options
| author | William Tu <u9012063@gmail.com> | 2016-06-20 07:26:17 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-06-22 16:34:39 -0400 |
| commit | b95e5928fcc76d156352570858abdea7b2628efd (patch) | |
| tree | a1957ca55d8e3a9d49af276d1b347340de0256c7 /net/openvswitch | |
| parent | 904632a224b2ea39920e526cdc93565aaf1fb43e (diff) | |
openvswitch: Add packet len info to upcall.
The commit f2a4d086ed4c ("openvswitch: Add packet truncation support.")
introduces packet truncation before sending to userspace upcall receiver.
This patch passes up the skb->len before truncation so that the upcall
receiver knows the original packet size. Potentially this will be used
by sFlow, where OVS translates sFlow config header=N to a sample action,
truncating packet to N byte in kernel datapath. Thus, only N bytes instead
of full-packet size is copied from kernel to userspace, saving the
kernel-to-userspace bandwidth.
Signed-off-by: William Tu <u9012063@gmail.com>
Cc: Pravin Shelar <pshelar@nicira.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/openvswitch')
| -rw-r--r-- | net/openvswitch/datapath.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c index 673934295333..524c0fd3078e 100644 --- a/net/openvswitch/datapath.c +++ b/net/openvswitch/datapath.c @@ -387,7 +387,8 @@ static size_t upcall_msg_size(const struct dp_upcall_info *upcall_info, { size_t size = NLMSG_ALIGN(sizeof(struct ovs_header)) + nla_total_size(hdrlen) /* OVS_PACKET_ATTR_PACKET */ - + nla_total_size(ovs_key_attr_size()); /* OVS_PACKET_ATTR_KEY */ + + nla_total_size(ovs_key_attr_size()) /* OVS_PACKET_ATTR_KEY */ + + nla_total_size(sizeof(unsigned int)); /* OVS_PACKET_ATTR_LEN */ /* OVS_PACKET_ATTR_USERDATA */ if (upcall_info->userdata) @@ -514,6 +515,16 @@ static int queue_userspace_packet(struct datapath *dp, struct sk_buff *skb, pad_packet(dp, user_skb); } + /* Add OVS_PACKET_ATTR_LEN when packet is truncated */ + if (cutlen > 0) { + if (nla_put_u32(user_skb, OVS_PACKET_ATTR_LEN, + skb->len)) { + err = -ENOBUFS; + goto out; + } + pad_packet(dp, user_skb); + } + /* Only reserve room for attribute header, packet data is added * in skb_zerocopy() */ if (!(nla = nla_reserve(user_skb, OVS_PACKET_ATTR_PACKET, 0))) { |