datapath: Avoid using stack larger than 1024.

commit (datapath: Refactor action alloc and copy api) effectively
reverted 1d2a1b5f5252e4c6ce8bbf8d91ca27aba52496e6 (datapath: Factor out
allocation and verification of actions.). This results in following
warning:

CC [M]  /home/jesse/openvswitch/datapath/linux/datapath.o
/home/jesse/openvswitch/datapath/linux/datapath.c: In function
‘ovs_flow_cmd_set’:
/home/jesse/openvswitch/datapath/linux/datapath.c:1094:1: warning: the
frame size of 1256 bytes is larger than 1024 bytes
[-Wframe-larger-than=]
 }

Following patch introduced the factoring back.

CC: Jesse Gross <jesse@nicira.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Jesse Gross <jesse@nicira.com>

diff --git a/datapath/datapath.c b/datapath/datapath.c
index f795e94..ab63791 100644 (file)
--- a/datapath/datapath.c
+++ b/datapath/datapath.c
@@ -990,6 +990,25 @@ error:
        return error;
 }
 
+/* Factor out action copy to avoid "Wframe-larger-than=1024" warning. */
+static struct sw_flow_actions *get_flow_actions(const struct nlattr *a,
+                                               const struct sw_flow_key *key,
+                                               const struct sw_flow_mask *mask)
+{
+       struct sw_flow_actions *acts;
+       struct sw_flow_key masked_key;
+       int error;
+
+       ovs_flow_mask_key(&masked_key, key, mask);
+       error = ovs_nla_copy_actions(a, &masked_key, &acts);
+       if (error) {
+               OVS_NLERR("Actions may not be safe on all matching packets.\n");
+               return ERR_PTR(error);
+       }
+
+       return acts;
+}
+
 static int ovs_flow_cmd_set(struct sk_buff *skb, struct genl_info *info)
 {
        struct nlattr **a = info->attrs;
@@ -1018,13 +1037,9 @@ static int ovs_flow_cmd_set(struct sk_buff *skb, struct genl_info *info)
 
        /* Validate actions. */
        if (a[OVS_FLOW_ATTR_ACTIONS]) {
-               struct sw_flow_key masked_key;
-
-               ovs_flow_mask_key(&masked_key, &key, &mask);
-               error = ovs_nla_copy_actions(a[OVS_FLOW_ATTR_ACTIONS],
-                                            &masked_key, &acts);
-               if (error) {
-                       OVS_NLERR("Flow actions may not be safe on all matching packets.\n");
+               acts = get_flow_actions(a[OVS_FLOW_ATTR_ACTIONS], &key, &mask);
+               if (IS_ERR(acts)) {
+                       error = PTR_ERR(acts);
                        goto error;
                }