datapath: add netlink error message to help kernel userspace integration.

[sliver-openvswitch.git] / datapath / datapath.c

diff --git a/datapath/datapath.c b/datapath/datapath.c
index 3680391..2f02f71 100644 (file)
--- a/datapath/datapath.c
+++ b/datapath/datapath.c
@@ -1126,7 +1126,7 @@ static int ovs_flow_cmd_fill_info(struct sw_flow *flow, struct datapath *dp,
                                  u32 seq, u32 flags, u8 cmd)
 {
        const int skb_orig_len = skb->len;
-       const struct sw_flow_actions *sf_acts;
+       struct sw_flow_mask *mask;
        struct nlattr *start;
        struct ovs_flow_stats stats;
        struct ovs_header *ovs_header;
@@ -1135,8 +1135,6 @@ static int ovs_flow_cmd_fill_info(struct sw_flow *flow, struct datapath *dp,
        u8 tcp_flags;
        int err;
 
-       sf_acts = ovsl_dereference(flow->sf_acts);
-
        ovs_header = genlmsg_put(skb, portid, seq, &dp_flow_genl_family, flags, cmd);
        if (!ovs_header)
                return -EMSGSIZE;
@@ -1158,8 +1156,8 @@ static int ovs_flow_cmd_fill_info(struct sw_flow *flow, struct datapath *dp,
        if (!nla)
                goto nla_put_failure;
 
-       err = ovs_flow_to_nlattrs(&flow->key,
-                       &ovsl_dereference(flow->mask)->key, skb);
+       mask = rcu_dereference_check(flow->mask, lockdep_ovsl_is_held());
+       err = ovs_flow_to_nlattrs(&flow->key, &mask->key, skb);
        if (err)
                goto error;
 
@@ -1197,6 +1195,11 @@ static int ovs_flow_cmd_fill_info(struct sw_flow *flow, struct datapath *dp,
         */
        start = nla_nest_start(skb, OVS_FLOW_ATTR_ACTIONS);
        if (start) {
+               const struct sw_flow_actions *sf_acts;
+
+               sf_acts = rcu_dereference_check(flow->sf_acts,
+                                               lockdep_ovsl_is_held());
+
                err = actions_to_attr(sf_acts->actions, sf_acts->actions_len, skb);
                if (!err)
                        nla_nest_end(skb, start);
@@ -1358,8 +1361,10 @@ static int ovs_flow_cmd_new_or_set(struct sk_buff *skb, struct genl_info *info)
 
                /* The unmasked key has to be the same for flow updates. */
                error = -EINVAL;
-               if (!ovs_flow_cmp_unmasked_key(flow, &key, match.range.end))
+               if (!ovs_flow_cmp_unmasked_key(flow, &key, match.range.end)) {
+                       OVS_NLERR("Flow modification message rejected, unmasked key does not match.\n");
                        goto err_unlock_ovs;
+               }
 
                /* Update actions. */
                old_acts = ovsl_dereference(flow->sf_acts);
@@ -1407,8 +1412,10 @@ static int ovs_flow_cmd_get(struct sk_buff *skb, struct genl_info *info)
        struct sw_flow_match match;
        int err;
 
-       if (!a[OVS_FLOW_ATTR_KEY])
+       if (!a[OVS_FLOW_ATTR_KEY]) {
+               OVS_NLERR("Flow get message rejected, Key attribute missing.\n");
                return -EINVAL;
+       }
 
        ovs_match_init(&match, &key, NULL);
        err = ovs_match_from_nlattrs(&match, a[OVS_FLOW_ATTR_KEY], NULL);
@@ -1507,15 +1514,14 @@ static int ovs_flow_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
        struct datapath *dp;
        struct flow_table *table;
 
-       ovs_lock();
+       rcu_read_lock();
        dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
        if (!dp) {
-               ovs_unlock();
+               rcu_read_unlock();
                return -ENODEV;
        }
 
-       table = ovsl_dereference(dp->table);
-
+       table = rcu_dereference(dp->table);
        for (;;) {
                struct sw_flow *flow;
                u32 bucket, obj;
@@ -1535,7 +1541,7 @@ static int ovs_flow_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
                cb->args[0] = bucket;
                cb->args[1] = obj;
        }
-       ovs_unlock();
+       rcu_read_unlock();
        return skb->len;
 }