[SOCK]: Introduce sk_clone

Out of tcp_create_openreq_child, will be used in
dccp_create_openreq_child, and is a nice sock function anyway.

Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 67 deletions

diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c
index 66ce1790a94f..8b6cd8d80662 100644
--- a/net/ipv4/tcp_minisocks.c
+++ b/net/ipv4/tcp_minisocks.c
@@ -599,67 +599,26 @@ out:
  */
 struct sock *tcp_create_openreq_child(struct sock *sk, struct request_sock *req, struct sk_buff *skb)
 {
-        /* allocate the newsk from the same slab of the master sock,
-         * if not, at sk_free time we'll try to free it from the wrong
-         * slabcache (i.e. is it TCPv4 or v6?), this is handled thru sk->sk_prot -acme */
-        struct sock *newsk = sk_alloc(PF_INET, GFP_ATOMIC, sk->sk_prot, 0);
+        struct sock *newsk = sk_clone(sk, GFP_ATOMIC);
 
-        if(newsk != NULL) {
+        if (newsk != NULL) {
                 struct inet_request_sock *ireq = inet_rsk(req);
                 struct tcp_request_sock *treq = tcp_rsk(req);
                 struct inet_sock *newinet = inet_sk(newsk);
                 struct tcp_sock *newtp;
-                struct sk_filter *filter;
 
-                memcpy(newsk, sk, sizeof(struct tcp_sock));
                 newsk->sk_state = TCP_SYN_RECV;
-
-                /* SANITY */
-                sk_node_init(&newsk->sk_node);
                 newinet->bind_hash = NULL;
 
                 /* Clone the TCP header template */
                 newinet->dport = ireq->rmt_port;
-
-                sock_lock_init(newsk);
-                bh_lock_sock(newsk);
-
-                rwlock_init(&newsk->sk_dst_lock);
-                newsk->sk_dst_cache = NULL;
-                atomic_set(&newsk->sk_rmem_alloc, 0);
-                skb_queue_head_init(&newsk->sk_receive_queue);
-                atomic_set(&newsk->sk_wmem_alloc, 0);
-                skb_queue_head_init(&newsk->sk_write_queue);
-                atomic_set(&newsk->sk_omem_alloc, 0);
-                newsk->sk_wmem_queued = 0;
-                newsk->sk_forward_alloc = 0;
-
-                sock_reset_flag(newsk, SOCK_DONE);
-                newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
-                newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
-                newsk->sk_send_head = NULL;
-                rwlock_init(&newsk->sk_callback_lock);
-                skb_queue_head_init(&newsk->sk_error_queue);
                 newsk->sk_write_space = sk_stream_write_space;
 
-                if ((filter = newsk->sk_filter) != NULL)
-                        sk_filter_charge(newsk, filter);
-
-                if (unlikely(xfrm_sk_clone_policy(newsk))) {
-                        /* It is still raw copy of parent, so invalidate
-                         * destructor and make plain sk_free() */
-                        newsk->sk_destruct = NULL;
-                        sk_free(newsk);
-                        return NULL;
-                }
-
                 /* Now setup tcp_sock */
                 newtp = tcp_sk(newsk);
                 newtp->pred_flags = 0;
                 newtp->rcv_nxt = treq->rcv_isn + 1;
-                newtp->snd_nxt = treq->snt_isn + 1;
-                newtp->snd_una = treq->snt_isn + 1;
-                newtp->snd_sml = treq->snt_isn + 1;
+                newtp->snd_nxt = newtp->snd_una = newtp->snd_sml = treq->snt_isn + 1;
 
                 tcp_prequeue_init(newtp);
 
@@ -710,32 +669,9 @@ struct sock *tcp_create_openreq_child(struct sock *sk, struct request_sock *req,
                 /* Deinitialize accept_queue to trap illegal accesses. */
                 memset(&newtp->accept_queue, 0, sizeof(newtp->accept_queue));
 
-                /* Back to base struct sock members. */
-                newsk->sk_err = 0;
-                newsk->sk_priority = 0;
-                atomic_set(&newsk->sk_refcnt, 2);
-
-                /*
-                 * Increment the counter in the same struct proto as the master
-                 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
-                 * is the same as sk->sk_prot->socks, as this field was copied
-                 * with memcpy), same rationale as the first comment in this
-                 * function.
-                 *
-                 * This _changes_ the previous behaviour, where
-                 * tcp_create_openreq_child always was incrementing the
-                 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
-                 * to be taken into account in all callers. -acme
-                 */
-                sk_refcnt_debug_inc(newsk);
-
-                atomic_inc(&tcp_sockets_allocated);
-
                 if (sock_flag(newsk, SOCK_KEEPOPEN))
                         tcp_reset_keepalive_timer(newsk,
                                                   keepalive_time_when(newtp));
-                newsk->sk_socket = NULL;
-                newsk->sk_sleep = NULL;
 
                 newtp->rx_opt.tstamp_ok = ireq->tstamp_ok;
                 if((newtp->rx_opt.sack_ok = ireq->sack_ok) != 0) {