mpls: Use definition for reserved label checks

In multiple locations there are checks for whether the label in hand
is a reserved label or not using the arbritray value of 16. Factor
this out into a #define for better maintainability and for
documentation.

Signed-off-by: Robert Shearman <rshearma@brocade.com>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/uapi/linux/mpls.h b/include/uapi/linux/mpls.h
index 139d4dd1cab83f1cee0399e9924138a24d350ba7..24a6cb1aec86f2a73ffcb717779249970bbb31dc 100644 (file)
--- a/include/uapi/linux/mpls.h
+++ b/include/uapi/linux/mpls.h
@@ -41,4 +41,6 @@ struct mpls_label {
 #define MPLS_LABEL_OAMALERT            14 /* RFC3429 */
 #define MPLS_LABEL_EXTENSION           15 /* RFC7274 */
 
+#define MPLS_LABEL_FIRST_UNRESERVED    16 /* RFC3032 */
+
 #endif /* _UAPI_MPLS_H */

diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c
index 88cfaa241c07b72650344da9097363f7fd85d5f2..b6b9a6c4e7849a35fa2161b7eafd41315b30208b 100644 (file)
--- a/net/mpls/af_mpls.c
+++ b/net/mpls/af_mpls.c
@@ -293,7 +293,7 @@ static void mpls_notify_route(struct net *net, unsigned index,
        struct mpls_route *rt = new ? new : old;
        unsigned nlm_flags = (old && new) ? NLM_F_REPLACE : 0;
        /* Ignore reserved labels for now */
-       if (rt && (index >= 16))
+       if (rt && (index >= MPLS_LABEL_FIRST_UNRESERVED))
                rtmsg_lfib(event, index, rt, nlh, net, portid, nlm_flags);
 }
 
@@ -327,7 +327,8 @@ static unsigned find_free_label(struct net *net)
 
        platform_label = rtnl_dereference(net->mpls.platform_label);
        platform_labels = net->mpls.platform_labels;
-       for (index = 16; index < platform_labels; index++) {
+       for (index = MPLS_LABEL_FIRST_UNRESERVED; index < platform_labels;
+            index++) {
                if (!rtnl_dereference(platform_label[index]))
                        return index;
        }
@@ -436,8 +437,8 @@ static int mpls_route_add(struct mpls_route_config *cfg)
                index = find_free_label(net);
        }
 
-       /* The first 16 labels are reserved, and may not be set */
-       if (index < 16)
+       /* Reserved labels may not be set */
+       if (index < MPLS_LABEL_FIRST_UNRESERVED)
                goto errout;
 
        /* The full 20 bit range may not be supported. */
@@ -516,8 +517,8 @@ static int mpls_route_del(struct mpls_route_config *cfg)
 
        index = cfg->rc_label;
 
-       /* The first 16 labels are reserved, and may not be removed */
-       if (index < 16)
+       /* Reserved labels may not be removed */
+       if (index < MPLS_LABEL_FIRST_UNRESERVED)
                goto errout;
 
        /* The full 20 bit range may not be supported */
@@ -835,8 +836,8 @@ static int rtm_to_route_config(struct sk_buff *skb,  struct nlmsghdr *nlh,
                                           &cfg->rc_label))
                                goto errout;
 
-                       /* The first 16 labels are reserved, and may not be set */
-                       if (cfg->rc_label < 16)
+                       /* Reserved labels may not be set */
+                       if (cfg->rc_label < MPLS_LABEL_FIRST_UNRESERVED)
                                goto errout;
 
                        break;
@@ -961,8 +962,8 @@ static int mpls_dump_routes(struct sk_buff *skb, struct netlink_callback *cb)
        ASSERT_RTNL();
 
        index = cb->args[0];
-       if (index < 16)
-               index = 16;
+       if (index < MPLS_LABEL_FIRST_UNRESERVED)
+               index = MPLS_LABEL_FIRST_UNRESERVED;
 
        platform_label = rtnl_dereference(net->mpls.platform_label);
        platform_labels = net->mpls.platform_labels;