datapath: Allow user space to announce ability to accept unaligned Netlink messages

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Reviewed-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>

diff --git a/datapath/datapath.c b/datapath/datapath.c
index 1808c36..08562a3 100644 (file)
--- a/datapath/datapath.c
+++ b/datapath/datapath.c
@@ -1045,6 +1045,7 @@ static struct genl_ops dp_flow_genl_ops[] = {
 static const struct nla_policy datapath_policy[OVS_DP_ATTR_MAX + 1] = {
        [OVS_DP_ATTR_NAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 },
        [OVS_DP_ATTR_UPCALL_PID] = { .type = NLA_U32 },
+       [OVS_DP_ATTR_USER_FEATURES] = { .type = NLA_U32 },
 };
 
 static struct genl_family dp_datapath_genl_family = {
@@ -1103,6 +1104,9 @@ static int ovs_dp_cmd_fill_info(struct datapath *dp, struct sk_buff *skb,
                        &dp_megaflow_stats))
                goto nla_put_failure;
 
+       if (nla_put_u32(skb, OVS_DP_ATTR_USER_FEATURES, dp->user_features))
+               goto nla_put_failure;
+
        return genlmsg_end(skb, ovs_header);
 
 nla_put_failure:
@@ -1149,6 +1153,12 @@ static struct datapath *lookup_datapath(struct net *net,
        return dp ? dp : ERR_PTR(-ENODEV);
 }
 
+static void ovs_dp_change(struct datapath *dp, struct nlattr **a)
+{
+       if (a[OVS_DP_ATTR_USER_FEATURES])
+               dp->user_features = nla_get_u32(a[OVS_DP_ATTR_USER_FEATURES]);
+}
+
 static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
 {
        struct nlattr **a = info->attrs;
@@ -1201,6 +1211,8 @@ static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
        parms.port_no = OVSP_LOCAL;
        parms.upcall_portid = nla_get_u32(a[OVS_DP_ATTR_UPCALL_PID]);
 
+       ovs_dp_change(dp, a);
+
        vport = new_vport(&parms);
        if (IS_ERR(vport)) {
                err = PTR_ERR(vport);
@@ -1304,6 +1316,8 @@ static int ovs_dp_cmd_set(struct sk_buff *skb, struct genl_info *info)
        if (IS_ERR(dp))
                goto unlock;
 
+       ovs_dp_change(dp, info->attrs);
+
        reply = ovs_dp_cmd_build_info(dp, info, OVS_DP_CMD_NEW);
        if (IS_ERR(reply)) {
                err = PTR_ERR(reply);

diff --git a/datapath/datapath.h b/datapath/datapath.h
index 89ba80f..b3ae7cd 100644 (file)
--- a/datapath/datapath.h
+++ b/datapath/datapath.h
@@ -90,6 +90,8 @@ struct datapath {
        /* Network namespace ref. */
        struct net *net;
 #endif
+
+       u32 user_features;
 };
 
 /**

diff --git a/include/linux/openvswitch.h b/include/linux/openvswitch.h
index b429201..585fa63 100644 (file)
--- a/include/linux/openvswitch.h
+++ b/include/linux/openvswitch.h
@@ -95,6 +95,7 @@ enum ovs_datapath_attr {
        OVS_DP_ATTR_UPCALL_PID,         /* Netlink PID to receive upcalls */
        OVS_DP_ATTR_STATS,              /* struct ovs_dp_stats */
        OVS_DP_ATTR_MEGAFLOW_STATS,     /* struct ovs_dp_megaflow_stats */
+       OVS_DP_ATTR_USER_FEATURES,      /* OVS_DP_F_*  */
        __OVS_DP_ATTR_MAX
 };
 
@@ -126,6 +127,9 @@ struct ovs_vport_stats {
        __u64   tx_dropped;             /* no space available in linux  */
 };
 
+/* Allow last Netlink attribute to be unaligned */
+#define OVS_DP_F_UNALIGNED     (1 << 0)
+
 /* Fixed logical ports. */
 #define OVSP_LOCAL      ((__u32)0)