openvswitch: Refactor ovs_flow_cmd_fill_info().

Split up ovs_flow_cmd_fill_info() to make it easier to cache parts of a
dump reply. This will be used to streamline flow_dump in a future patch.

Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Thomas Graf <tgraf@noironetworks.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>

diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
index 04a26ae..bbb920b 100644 (file)
--- a/net/openvswitch/datapath.c
+++ b/net/openvswitch/datapath.c
@@ -674,58 +674,67 @@ static size_t ovs_flow_cmd_msg_size(const struct sw_flow_actions *acts)
 }
 
 /* Called with ovs_mutex or RCU read lock. */
-static int ovs_flow_cmd_fill_info(const struct sw_flow *flow, int dp_ifindex,
-                                 struct sk_buff *skb, u32 portid,
-                                 u32 seq, u32 flags, u8 cmd)
+static int ovs_flow_cmd_fill_match(const struct sw_flow *flow,
+                                  struct sk_buff *skb)
 {
-       const int skb_orig_len = skb->len;
-       struct nlattr *start;
-       struct ovs_flow_stats stats;
-       __be16 tcp_flags;
-       unsigned long used;
-       struct ovs_header *ovs_header;
        struct nlattr *nla;
        int err;
 
-       ovs_header = genlmsg_put(skb, portid, seq, &dp_flow_genl_family, flags, cmd);
-       if (!ovs_header)
-               return -EMSGSIZE;
-
-       ovs_header->dp_ifindex = dp_ifindex;
-
        /* Fill flow key. */
        nla = nla_nest_start(skb, OVS_FLOW_ATTR_KEY);
        if (!nla)
-               goto nla_put_failure;
+               return -EMSGSIZE;
 
        err = ovs_nla_put_flow(&flow->unmasked_key, &flow->unmasked_key, skb);
        if (err)
-               goto error;
+               return err;
+
        nla_nest_end(skb, nla);
 
+       /* Fill flow mask. */
        nla = nla_nest_start(skb, OVS_FLOW_ATTR_MASK);
        if (!nla)
-               goto nla_put_failure;
+               return -EMSGSIZE;
 
        err = ovs_nla_put_flow(&flow->key, &flow->mask->key, skb);
        if (err)
-               goto error;
+               return err;
 
        nla_nest_end(skb, nla);
+       return 0;
+}
+
+/* Called with ovs_mutex or RCU read lock. */
+static int ovs_flow_cmd_fill_stats(const struct sw_flow *flow,
+                                  struct sk_buff *skb)
+{
+       struct ovs_flow_stats stats;
+       __be16 tcp_flags;
+       unsigned long used;
 
        ovs_flow_stats_get(flow, &stats, &used, &tcp_flags);
 
        if (used &&
            nla_put_u64(skb, OVS_FLOW_ATTR_USED, ovs_flow_used_time(used)))
-               goto nla_put_failure;
+               return -EMSGSIZE;
 
        if (stats.n_packets &&
            nla_put(skb, OVS_FLOW_ATTR_STATS, sizeof(struct ovs_flow_stats), &stats))
-               goto nla_put_failure;
+               return -EMSGSIZE;
 
        if ((u8)ntohs(tcp_flags) &&
             nla_put_u8(skb, OVS_FLOW_ATTR_TCP_FLAGS, (u8)ntohs(tcp_flags)))
-               goto nla_put_failure;
+               return -EMSGSIZE;
+
+       return 0;
+}
+
+/* Called with ovs_mutex or RCU read lock. */
+static int ovs_flow_cmd_fill_actions(const struct sw_flow *flow,
+                                    struct sk_buff *skb, int skb_orig_len)
+{
+       struct nlattr *start;
+       int err;
 
        /* If OVS_FLOW_ATTR_ACTIONS doesn't fit, skip dumping the actions if
         * this is the first flow to be dumped into 'skb'.  This is unusual for
@@ -749,17 +758,47 @@ static int ovs_flow_cmd_fill_info(const struct sw_flow *flow, int dp_ifindex,
                        nla_nest_end(skb, start);
                else {
                        if (skb_orig_len)
-                               goto error;
+                               return err;
 
                        nla_nest_cancel(skb, start);
                }
-       } else if (skb_orig_len)
-               goto nla_put_failure;
+       } else if (skb_orig_len) {
+               return -EMSGSIZE;
+       }
+
+       return 0;
+}
+
+/* Called with ovs_mutex or RCU read lock. */
+static int ovs_flow_cmd_fill_info(const struct sw_flow *flow, int dp_ifindex,
+                                 struct sk_buff *skb, u32 portid,
+                                 u32 seq, u32 flags, u8 cmd)
+{
+       const int skb_orig_len = skb->len;
+       struct ovs_header *ovs_header;
+       int err;
+
+       ovs_header = genlmsg_put(skb, portid, seq, &dp_flow_genl_family,
+                                flags, cmd);
+       if (!ovs_header)
+               return -EMSGSIZE;
+
+       ovs_header->dp_ifindex = dp_ifindex;
+
+       err = ovs_flow_cmd_fill_match(flow, skb);
+       if (err)
+               goto error;
+
+       err = ovs_flow_cmd_fill_stats(flow, skb);
+       if (err)
+               goto error;
+
+       err = ovs_flow_cmd_fill_actions(flow, skb, skb_orig_len);
+       if (err)
+               goto error;
 
        return genlmsg_end(skb, ovs_header);
 
-nla_put_failure:
-       err = -EMSGSIZE;
 error:
        genlmsg_cancel(skb, ovs_header);
        return err;