[NETLINK]: Make netlink_callback->done() optional

Most netlink families make no use of the done() callback, making
it optional gets rid of all unnecessary dummy implementations.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 8 insertions, 25 deletions

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 9bed7569ce3f..193fd8637f9f 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -462,11 +462,6 @@ void rtmsg_ifinfo(int type, struct net_device *dev, unsigned change)
         netlink_broadcast(rtnl, skb, 0, RTNLGRP_LINK, GFP_KERNEL);
 }
 
-static int rtnetlink_done(struct netlink_callback *cb)
-{
-        return 0;
-}
-
 /* Protected by RTNL sempahore.  */
 static struct rtattr **rta_buf;
 static int rtattr_max;
@@ -533,8 +528,7 @@ rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, int *errp)
                         goto err_inval;
 
                 if ((*errp = netlink_dump_start(rtnl, skb, nlh,
-                                                link->dumpit,
-                                                rtnetlink_done)) != 0) {
+                                                link->dumpit, NULL)) != 0) {
                         return -1;
                 }
                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
index 71f3c7350c6e..39061ed53cfd 100644
--- a/net/ipv4/inet_diag.c
+++ b/net/ipv4/inet_diag.c
@@ -724,12 +724,6 @@ done:
         return skb->len;
 }
 
-static int inet_diag_dump_done(struct netlink_callback *cb)
-{
-        return 0;
-}
-
-
 static __inline__ int
 inet_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
@@ -760,8 +754,7 @@ inet_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
                                 goto err_inval;
                 }
                 return netlink_dump_start(idiagnl, skb, nlh,
-                                          inet_diag_dump,
-                                          inet_diag_dump_done);
+                                          inet_diag_dump, NULL);
         } else {
                 return inet_diag_get_exact(skb, nlh);
         }
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 227e99ed510c..f7f42c3e96cb 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -1710,7 +1710,7 @@ static void fib6_dump_end(struct netlink_callback *cb)
 static int fib6_dump_done(struct netlink_callback *cb)
 {
         fib6_dump_end(cb);
-        return cb->done(cb);
+        return cb->done ? cb->done(cb) : 0;
 }
 
 int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 5ca283537bc6..f3fb7e575816 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -427,7 +427,8 @@ static int netlink_release(struct socket *sock)
 
         spin_lock(&nlk->cb_lock);
         if (nlk->cb) {
-                nlk->cb->done(nlk->cb);
+                if (nlk->cb->done)
+                        nlk->cb->done(nlk->cb);
                 netlink_destroy_callback(nlk->cb);
                 nlk->cb = NULL;
         }
@@ -1322,7 +1323,8 @@ static int netlink_dump(struct sock *sk)
         skb_queue_tail(&sk->sk_receive_queue, skb);
         sk->sk_data_ready(sk, skb->len);
 
-        cb->done(cb);
+        if (cb->done)
+                cb->done(cb);
         nlk->cb = NULL;
         spin_unlock(&nlk->cb_lock);
 
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index c35336a0f71b..6996b7e85665 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -948,11 +948,6 @@ static struct xfrm_link {
         [XFRM_MSG_FLUSHPOLICY - XFRM_MSG_BASE] = { .doit = xfrm_flush_policy  },
 };
 
-static int xfrm_done(struct netlink_callback *cb)
-{
-        return 0;
-}
-
 static int xfrm_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, int *errp)
 {
         struct rtattr *xfrma[XFRMA_MAX];
@@ -990,8 +985,7 @@ static int xfrm_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, int *err
                         goto err_einval;
 
                 if ((*errp = netlink_dump_start(xfrm_nl, skb, nlh,
-                                                link->dump,
-                                                xfrm_done)) != 0) {
+                                                link->dump, NULL)) != 0) {
                         return -1;
                 }
                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);