tipc: modify socket iterator for sock_diag

The current socket iterator function tipc_nl_sk_dump, handles socket
locks and calls __tipc_nl_add_sk for each socket.
To reuse this logic in sock_diag implementation, we do minor
modifications to make these functions generic as described below.

In this commit, we add a two new functions __tipc_nl_sk_walk,
__tipc_nl_add_sk_info and modify tipc_nl_sk_dump, __tipc_nl_add_sk
accordingly.

In __tipc_nl_sk_walk we:
1. acquire and release socket locks
2. for each socket, execute the specified callback function

In __tipc_nl_add_sk we:
- Move the netlink attribute insertion to __tipc_nl_add_sk_info.

tipc_nl_sk_dump calls tipc_nl_sk_walk with __tipc_nl_add_sk as argument.

sock_diag will use these generic functions in a later commit.

There is no functional change in this commit.
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: GhantaKrishnamurthy MohanKrishna <mohan.krishna.ghanta.krishnamurthy@ericsson.com>
Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index a4a9148d462900db9fa38df92f38c9d1e9c4881a..35ac0f5b9529f21c9b0c4b4e79b353f7516245ef 100644 (file)
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -3160,16 +3160,33 @@ msg_full:
        return -EMSGSIZE;
 }
 
+static int __tipc_nl_add_sk_info(struct sk_buff *skb, struct tipc_sock
+                         *tsk)
+{
+       struct net *net = sock_net(skb->sk);
+       struct tipc_net *tn = tipc_net(net);
+       struct sock *sk = &tsk->sk;
+
+       if (nla_put_u32(skb, TIPC_NLA_SOCK_REF, tsk->portid) ||
+           nla_put_u32(skb, TIPC_NLA_SOCK_ADDR, tn->own_addr))
+               return -EMSGSIZE;
+
+       if (tipc_sk_connected(sk)) {
+               if (__tipc_nl_add_sk_con(skb, tsk))
+                       return -EMSGSIZE;
+       } else if (!list_empty(&tsk->publications)) {
+               if (nla_put_flag(skb, TIPC_NLA_SOCK_HAS_PUBL))
+                       return -EMSGSIZE;
+       }
+       return 0;
+}
+
 /* Caller should hold socket lock for the passed tipc socket. */
 static int __tipc_nl_add_sk(struct sk_buff *skb, struct netlink_callback *cb,
                            struct tipc_sock *tsk)
 {
-       int err;
-       void *hdr;
        struct nlattr *attrs;
-       struct net *net = sock_net(skb->sk);
-       struct tipc_net *tn = net_generic(net, tipc_net_id);
-       struct sock *sk = &tsk->sk;
+       void *hdr;
 
        hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
                          &tipc_genl_family, NLM_F_MULTI, TIPC_NL_SOCK_GET);
@@ -3179,19 +3196,10 @@ static int __tipc_nl_add_sk(struct sk_buff *skb, struct netlink_callback *cb,
        attrs = nla_nest_start(skb, TIPC_NLA_SOCK);
        if (!attrs)
                goto genlmsg_cancel;
-       if (nla_put_u32(skb, TIPC_NLA_SOCK_REF, tsk->portid))
-               goto attr_msg_cancel;
-       if (nla_put_u32(skb, TIPC_NLA_SOCK_ADDR, tn->own_addr))
+
+       if (__tipc_nl_add_sk_info(skb, tsk))
                goto attr_msg_cancel;
 
-       if (tipc_sk_connected(sk)) {
-               err = __tipc_nl_add_sk_con(skb, tsk);
-               if (err)
-                       goto attr_msg_cancel;
-       } else if (!list_empty(&tsk->publications)) {
-               if (nla_put_flag(skb, TIPC_NLA_SOCK_HAS_PUBL))
-                       goto attr_msg_cancel;
-       }
        nla_nest_end(skb, attrs);
        genlmsg_end(skb, hdr);
 
@@ -3205,16 +3213,19 @@ msg_cancel:
        return -EMSGSIZE;
 }
 
-int tipc_nl_sk_dump(struct sk_buff *skb, struct netlink_callback *cb)
+static int __tipc_nl_sk_walk(struct sk_buff *skb, struct netlink_callback *cb,
+                            int (*skb_handler)(struct sk_buff *skb,
+                                               struct netlink_callback *cb,
+                                               struct tipc_sock *tsk))
 {
-       int err;
-       struct tipc_sock *tsk;
-       const struct bucket_table *tbl;
-       struct rhash_head *pos;
        struct net *net = sock_net(skb->sk);
-       struct tipc_net *tn = net_generic(net, tipc_net_id);
-       u32 tbl_id = cb->args[0];
+       struct tipc_net *tn = tipc_net(net);
+       const struct bucket_table *tbl;
        u32 prev_portid = cb->args[1];
+       u32 tbl_id = cb->args[0];
+       struct rhash_head *pos;
+       struct tipc_sock *tsk;
+       int err;
 
        rcu_read_lock();
        tbl = rht_dereference_rcu((&tn->sk_rht)->tbl, &tn->sk_rht);
@@ -3226,12 +3237,13 @@ int tipc_nl_sk_dump(struct sk_buff *skb, struct netlink_callback *cb)
                                continue;
                        }
 
-                       err = __tipc_nl_add_sk(skb, cb, tsk);
+                       err = skb_handler(skb, cb, tsk);
                        if (err) {
                                prev_portid = tsk->portid;
                                spin_unlock_bh(&tsk->sk.sk_lock.slock);
                                goto out;
                        }
+
                        prev_portid = 0;
                        spin_unlock_bh(&tsk->sk.sk_lock.slock);
                }
@@ -3244,6 +3256,11 @@ out:
        return skb->len;
 }
 
+int tipc_nl_sk_dump(struct sk_buff *skb, struct netlink_callback *cb)
+{
+       return __tipc_nl_sk_walk(skb, cb, __tipc_nl_add_sk);
+}
+
 /* Caller should hold socket lock for the passed tipc socket. */
 static int __tipc_nl_add_sk_publ(struct sk_buff *skb,
                                 struct netlink_callback *cb,