Re: [PATCHv4 net-next 06/10] openvswitch: Allow matching on conntrack mark

Allow matching and setting the conntrack mark field. As with conntrack
state and zone, these are populated when the CT action is executed,
and are made available for matching via RECIRC. To write to this field,
a value and optional mark can be passed as part of the conntrack action.

E.g.: actions:ct(zone=0),ct(zone=1,mark=1)

This will perform conntrack lookup in zone 0, then lookup in zone 1,
then modify the mark for the entry in zone 1. The conntrack entry itself
must be committed using the "commit" flag in the conntrack action flags
for this change to persist.

Signed-off-by: Justin Pettit <redacted>
Signed-off-by: Joe Stringer <redacted>
---
v1-v3: No change.
v4: Only allow setting conntrack mark via ct action.
    Documentation tweaks.
---
 include/uapi/linux/openvswitch.h |  5 ++++
 net/openvswitch/actions.c        |  1 +
 net/openvswitch/conntrack.c      | 61 ++++++++++++++++++++++++++++++++++++++--
 net/openvswitch/conntrack.h      |  1 +
 net/openvswitch/flow.h           |  1 +
 net/openvswitch/flow_netlink.c   | 15 +++++++++-
 6 files changed, 80 insertions(+), 4 deletions(-)

diff --git a/include/uapi/linux/openvswitch.h b/include/uapi/linux/openvswitch.h
index 55f5997..7a185b5 100644
--- a/include/uapi/linux/openvswitch.h
+++ b/include/uapi/linux/openvswitch.h

@@ -325,6 +325,7 @@ enum ovs_key_attr {
                                 * the accepted length of the array. */
        OVS_KEY_ATTR_CT_STATE,  /* u8 bitmask of OVS_CS_F_* */
        OVS_KEY_ATTR_CT_ZONE,   /* u16 connection tracking zone. */
+       OVS_KEY_ATTR_CT_MARK,   /* u32 connection tracking mark */

 #ifdef __KERNEL__
        OVS_KEY_ATTR_TUNNEL_INFO,  /* struct ip_tunnel_info */

@@ -613,11 +614,15 @@ struct ovs_action_hash {
  * enum ovs_ct_attr - Attributes for %OVS_ACTION_ATTR_CT action.
  * @OVS_CT_ATTR_FLAGS: u32 connection tracking flags.
  * @OVS_CT_ATTR_ZONE: u16 connection tracking zone.
+ * @OVS_CT_ATTR_MARK: u32 value followed by u32 mask. For each bit set in the
+ * mask, the corresponding bit in the value is copied to the connection
+ * tracking mark field in the connection.
  */
 enum ovs_ct_attr {
        OVS_CT_ATTR_UNSPEC,
        OVS_CT_ATTR_FLAGS,      /* u8 bitmask of OVS_CT_F_*. */
        OVS_CT_ATTR_ZONE,       /* u16 zone id. */
+       OVS_CT_ATTR_MARK,       /* mark to associate with this connection. */
        __OVS_CT_ATTR_MAX
 };