net/rds/tcp.c - linux - Git at Google

 /*
  * Copyright (c) 2006 Oracle.  All rights reserved.
  *
  * This software is available to you under a choice of one of two
  * licenses.  You may choose to be licensed under the terms of the GNU
  * General Public License (GPL) Version 2, available from the file
  * COPYING in the main directory of this source tree, or the
  * OpenIB.org BSD license below:
  *
  *     Redistribution and use in source and binary forms, with or
  *     without modification, are permitted provided that the following
  *     conditions are met:
  *
  *      - Redistributions of source code must retain the above
  *        copyright notice, this list of conditions and the following
  *        disclaimer.
  *
  *      - Redistributions in binary form must reproduce the above
  *        copyright notice, this list of conditions and the following
  *        disclaimer in the documentation and/or other materials
  *        provided with the distribution.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  *
  */
 #include <linux/kernel.h>
 #include <linux/slab.h>
 #include <linux/in.h>
 #include <linux/module.h>
 #include <net/tcp.h>

 #include "rds.h"
 #include "tcp.h"

 /* only for info exporting */
 static DEFINE_SPINLOCK(rds_tcp_tc_list_lock);
 static LIST_HEAD(rds_tcp_tc_list);
 static unsigned int rds_tcp_tc_count;

 /* Track rds_tcp_connection structs so they can be cleaned up */
 static DEFINE_SPINLOCK(rds_tcp_conn_lock);
 static LIST_HEAD(rds_tcp_conn_list);

 static struct kmem_cache *rds_tcp_conn_slab;

 #define RDS_TCP_DEFAULT_BUFSIZE (128 * 1024)

 /* doing it this way avoids calling tcp_sk() */
 void rds_tcp_nonagle(struct socket *sock)
 {
 	mm_segment_t oldfs = get_fs();
 	int val = 1;

 	set_fs(KERNEL_DS);
 	sock->ops->setsockopt(sock, SOL_TCP, TCP_NODELAY, (char __user *)&val,
 			      sizeof(val));
 	set_fs(oldfs);
 }

 void rds_tcp_tune(struct socket *sock)
 {
 	struct sock *sk = sock->sk;

 	rds_tcp_nonagle(sock);

 	/*
 	 * We're trying to saturate gigabit with the default,
 	 * see svc_sock_setbufsize().
 	 */
 	lock_sock(sk);
 	sk->sk_sndbuf = RDS_TCP_DEFAULT_BUFSIZE;
 	sk->sk_rcvbuf = RDS_TCP_DEFAULT_BUFSIZE;
 	sk->sk_userlocks |= SOCK_SNDBUF_LOCK|SOCK_RCVBUF_LOCK;
 	release_sock(sk);
 }

 u32 rds_tcp_snd_nxt(struct rds_tcp_connection *tc)
 {
 	return tcp_sk(tc->t_sock->sk)->snd_nxt;
 }

 u32 rds_tcp_snd_una(struct rds_tcp_connection *tc)
 {
 	return tcp_sk(tc->t_sock->sk)->snd_una;
 }

 void rds_tcp_restore_callbacks(struct socket *sock,
 			       struct rds_tcp_connection *tc)
 {
 	rdsdebug("restoring sock %p callbacks from tc %p\n", sock, tc);
 	write_lock_bh(&sock->sk->sk_callback_lock);

 	/* done under the callback_lock to serialize with write_space */
 	spin_lock(&rds_tcp_tc_list_lock);
 	list_del_init(&tc->t_list_item);
 	rds_tcp_tc_count--;
 	spin_unlock(&rds_tcp_tc_list_lock);

 	tc->t_sock = NULL;

 	sock->sk->sk_write_space = tc->t_orig_write_space;
 	sock->sk->sk_data_ready = tc->t_orig_data_ready;
 	sock->sk->sk_state_change = tc->t_orig_state_change;
 	sock->sk->sk_user_data = NULL;

 	write_unlock_bh(&sock->sk->sk_callback_lock);
 }

 /*
  * This is the only path that sets tc->t_sock.  Send and receive trust that
  * it is set.  The RDS_CONN_CONNECTED bit protects those paths from being
  * called while it isn't set.
  */
 void rds_tcp_set_callbacks(struct socket *sock, struct rds_connection *conn)
 {
 	struct rds_tcp_connection *tc = conn->c_transport_data;

 	rdsdebug("setting sock %p callbacks to tc %p\n", sock, tc);
 	write_lock_bh(&sock->sk->sk_callback_lock);

 	/* done under the callback_lock to serialize with write_space */
 	spin_lock(&rds_tcp_tc_list_lock);
 	list_add_tail(&tc->t_list_item, &rds_tcp_tc_list);
 	rds_tcp_tc_count++;
 	spin_unlock(&rds_tcp_tc_list_lock);

 	/* accepted sockets need our listen data ready undone */
 	if (sock->sk->sk_data_ready == rds_tcp_listen_data_ready)
 		sock->sk->sk_data_ready = sock->sk->sk_user_data;

 	tc->t_sock = sock;
 	tc->conn = conn;
 	tc->t_orig_data_ready = sock->sk->sk_data_ready;
 	tc->t_orig_write_space = sock->sk->sk_write_space;
 	tc->t_orig_state_change = sock->sk->sk_state_change;

 	sock->sk->sk_user_data = conn;
 	sock->sk->sk_data_ready = rds_tcp_data_ready;
 	sock->sk->sk_write_space = rds_tcp_write_space;
 	sock->sk->sk_state_change = rds_tcp_state_change;

 	write_unlock_bh(&sock->sk->sk_callback_lock);
 }

 static void rds_tcp_tc_info(struct socket *sock, unsigned int len,
 			    struct rds_info_iterator *iter,
 			    struct rds_info_lengths *lens)
 {
 	struct rds_info_tcp_socket tsinfo;
 	struct rds_tcp_connection *tc;
 	unsigned long flags;
 	struct sockaddr_in sin;
 	int sinlen;

 	spin_lock_irqsave(&rds_tcp_tc_list_lock, flags);

 	if (len / sizeof(tsinfo) < rds_tcp_tc_count)
 		goto out;

 	list_for_each_entry(tc, &rds_tcp_tc_list, t_list_item) {

 		sock->ops->getname(sock, (struct sockaddr *)&sin, &sinlen, 0);
 		tsinfo.local_addr = sin.sin_addr.s_addr;
 		tsinfo.local_port = sin.sin_port;
 		sock->ops->getname(sock, (struct sockaddr *)&sin, &sinlen, 1);
 		tsinfo.peer_addr = sin.sin_addr.s_addr;
 		tsinfo.peer_port = sin.sin_port;

 		tsinfo.hdr_rem = tc->t_tinc_hdr_rem;
 		tsinfo.data_rem = tc->t_tinc_data_rem;
 		tsinfo.last_sent_nxt = tc->t_last_sent_nxt;
 		tsinfo.last_expected_una = tc->t_last_expected_una;
 		tsinfo.last_seen_una = tc->t_last_seen_una;

 		rds_info_copy(iter, &tsinfo, sizeof(tsinfo));
 	}

 out:
 	lens->nr = rds_tcp_tc_count;
 	lens->each = sizeof(tsinfo);

 	spin_unlock_irqrestore(&rds_tcp_tc_list_lock, flags);
 }

 static int rds_tcp_laddr_check(__be32 addr)
 {
 	if (inet_addr_type(&init_net, addr) == RTN_LOCAL)
 		return 0;
 	return -EADDRNOTAVAIL;
 }

 static int rds_tcp_conn_alloc(struct rds_connection *conn, gfp_t gfp)
 {
 	struct rds_tcp_connection *tc;

 	tc = kmem_cache_alloc(rds_tcp_conn_slab, gfp);
 	if (!tc)
 		return -ENOMEM;

 	tc->t_sock = NULL;
 	tc->t_tinc = NULL;
 	tc->t_tinc_hdr_rem = sizeof(struct rds_header);
 	tc->t_tinc_data_rem = 0;

 	conn->c_transport_data = tc;

 	spin_lock_irq(&rds_tcp_conn_lock);
 	list_add_tail(&tc->t_tcp_node, &rds_tcp_conn_list);
 	spin_unlock_irq(&rds_tcp_conn_lock);

 	rdsdebug("alloced tc %p\n", conn->c_transport_data);
 	return 0;
 }

 static void rds_tcp_conn_free(void *arg)
 {
 	struct rds_tcp_connection *tc = arg;
 	unsigned long flags;
 	rdsdebug("freeing tc %p\n", tc);

 	spin_lock_irqsave(&rds_tcp_conn_lock, flags);
 	list_del(&tc->t_tcp_node);
 	spin_unlock_irqrestore(&rds_tcp_conn_lock, flags);

 	kmem_cache_free(rds_tcp_conn_slab, tc);
 }

 static void rds_tcp_destroy_conns(void)
 {
 	struct rds_tcp_connection *tc, *_tc;
 	LIST_HEAD(tmp_list);

 	/* avoid calling conn_destroy with irqs off */
 	spin_lock_irq(&rds_tcp_conn_lock);
 	list_splice(&rds_tcp_conn_list, &tmp_list);
 	INIT_LIST_HEAD(&rds_tcp_conn_list);
 	spin_unlock_irq(&rds_tcp_conn_lock);

 	list_for_each_entry_safe(tc, _tc, &tmp_list, t_tcp_node) {
 		if (tc->conn->c_passive)
 			rds_conn_destroy(tc->conn->c_passive);
 		rds_conn_destroy(tc->conn);
 	}
 }

 static void rds_tcp_exit(void)
 {
 	rds_info_deregister_func(RDS_INFO_TCP_SOCKETS, rds_tcp_tc_info);
 	rds_tcp_listen_stop();
 	rds_tcp_destroy_conns();
 	rds_trans_unregister(&rds_tcp_transport);
 	rds_tcp_recv_exit();
 	kmem_cache_destroy(rds_tcp_conn_slab);
 }
 module_exit(rds_tcp_exit);

 struct rds_transport rds_tcp_transport = {
 	.laddr_check		= rds_tcp_laddr_check,
 	.xmit_prepare		= rds_tcp_xmit_prepare,
 	.xmit_complete		= rds_tcp_xmit_complete,
 	.xmit			= rds_tcp_xmit,
 	.recv			= rds_tcp_recv,
 	.conn_alloc		= rds_tcp_conn_alloc,
 	.conn_free		= rds_tcp_conn_free,
 	.conn_connect		= rds_tcp_conn_connect,
 	.conn_shutdown		= rds_tcp_conn_shutdown,
 	.inc_copy_to_user	= rds_tcp_inc_copy_to_user,
 	.inc_free		= rds_tcp_inc_free,
 	.stats_info_copy	= rds_tcp_stats_info_copy,
 	.exit			= rds_tcp_exit,
 	.t_owner		= THIS_MODULE,
 	.t_name			= "tcp",
 	.t_type			= RDS_TRANS_TCP,
 	.t_prefer_loopback	= 1,
 };

 static int rds_tcp_init(void)
 {
 	int ret;

 	rds_tcp_conn_slab = kmem_cache_create("rds_tcp_connection",
 					      sizeof(struct rds_tcp_connection),
 					      0, 0, NULL);
 	if (!rds_tcp_conn_slab) {
 		ret = -ENOMEM;
 		goto out;
 	}

 	ret = rds_tcp_recv_init();
 	if (ret)
 		goto out_slab;

 	ret = rds_trans_register(&rds_tcp_transport);
 	if (ret)
 		goto out_recv;

 	ret = rds_tcp_listen_init();
 	if (ret)
 		goto out_register;

 	rds_info_register_func(RDS_INFO_TCP_SOCKETS, rds_tcp_tc_info);

 	goto out;

 out_register:
 	rds_trans_unregister(&rds_tcp_transport);
 out_recv:
 	rds_tcp_recv_exit();
 out_slab:
 	kmem_cache_destroy(rds_tcp_conn_slab);
 out:
 	return ret;
 }
 module_init(rds_tcp_init);

 MODULE_AUTHOR("Oracle Corporation <rds-devel@oss.oracle.com>");
 MODULE_DESCRIPTION("RDS: TCP transport");
 MODULE_LICENSE("Dual BSD/GPL");
	/*
	* Copyright (c) 2006 Oracle. All rights reserved.
	*
	* This software is available to you under a choice of one of two
	* licenses. You may choose to be licensed under the terms of the GNU
	* General Public License (GPL) Version 2, available from the file
	* COPYING in the main directory of this source tree, or the
	* OpenIB.org BSD license below:
	*
	* Redistribution and use in source and binary forms, with or
	* without modification, are permitted provided that the following
	* conditions are met:
	*
	* - Redistributions of source code must retain the above
	* copyright notice, this list of conditions and the following
	* disclaimer.
	*
	* - Redistributions in binary form must reproduce the above
	* copyright notice, this list of conditions and the following
	* disclaimer in the documentation and/or other materials
	* provided with the distribution.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	* SOFTWARE.
	*
	*/
	#include <linux/kernel.h>
	#include <linux/slab.h>
	#include <linux/in.h>
	#include <linux/module.h>
	#include <net/tcp.h>

	#include "rds.h"
	#include "tcp.h"

	/* only for info exporting */
	static DEFINE_SPINLOCK(rds_tcp_tc_list_lock);
	static LIST_HEAD(rds_tcp_tc_list);
	static unsigned int rds_tcp_tc_count;

	/* Track rds_tcp_connection structs so they can be cleaned up */
	static DEFINE_SPINLOCK(rds_tcp_conn_lock);
	static LIST_HEAD(rds_tcp_conn_list);

	static struct kmem_cache *rds_tcp_conn_slab;

	#define RDS_TCP_DEFAULT_BUFSIZE (128 * 1024)

	/* doing it this way avoids calling tcp_sk() */
	void rds_tcp_nonagle(struct socket *sock)
	{
	mm_segment_t oldfs = get_fs();
	int val = 1;

	set_fs(KERNEL_DS);
	sock->ops->setsockopt(sock, SOL_TCP, TCP_NODELAY, (char __user *)&val,
	sizeof(val));
	set_fs(oldfs);
	}

	void rds_tcp_tune(struct socket *sock)
	{
	struct sock *sk = sock->sk;

	rds_tcp_nonagle(sock);

	/*
	* We're trying to saturate gigabit with the default,
	* see svc_sock_setbufsize().
	*/
	lock_sock(sk);
	sk->sk_sndbuf = RDS_TCP_DEFAULT_BUFSIZE;
	sk->sk_rcvbuf = RDS_TCP_DEFAULT_BUFSIZE;
	sk->sk_userlocks \|= SOCK_SNDBUF_LOCK\|SOCK_RCVBUF_LOCK;
	release_sock(sk);
	}

	u32 rds_tcp_snd_nxt(struct rds_tcp_connection *tc)
	{
	return tcp_sk(tc->t_sock->sk)->snd_nxt;
	}

	u32 rds_tcp_snd_una(struct rds_tcp_connection *tc)
	{
	return tcp_sk(tc->t_sock->sk)->snd_una;
	}

	void rds_tcp_restore_callbacks(struct socket *sock,
	struct rds_tcp_connection *tc)
	{
	rdsdebug("restoring sock %p callbacks from tc %p\n", sock, tc);
	write_lock_bh(&sock->sk->sk_callback_lock);

	/* done under the callback_lock to serialize with write_space */
	spin_lock(&rds_tcp_tc_list_lock);
	list_del_init(&tc->t_list_item);
	rds_tcp_tc_count--;
	spin_unlock(&rds_tcp_tc_list_lock);

	tc->t_sock = NULL;

	sock->sk->sk_write_space = tc->t_orig_write_space;
	sock->sk->sk_data_ready = tc->t_orig_data_ready;
	sock->sk->sk_state_change = tc->t_orig_state_change;
	sock->sk->sk_user_data = NULL;

	write_unlock_bh(&sock->sk->sk_callback_lock);
	}

	/*
	* This is the only path that sets tc->t_sock. Send and receive trust that
	* it is set. The RDS_CONN_CONNECTED bit protects those paths from being
	* called while it isn't set.
	*/
	void rds_tcp_set_callbacks(struct socket sock, struct rds_connection conn)
	{
	struct rds_tcp_connection *tc = conn->c_transport_data;

	rdsdebug("setting sock %p callbacks to tc %p\n", sock, tc);
	write_lock_bh(&sock->sk->sk_callback_lock);

	/* done under the callback_lock to serialize with write_space */
	spin_lock(&rds_tcp_tc_list_lock);
	list_add_tail(&tc->t_list_item, &rds_tcp_tc_list);
	rds_tcp_tc_count++;
	spin_unlock(&rds_tcp_tc_list_lock);

	/* accepted sockets need our listen data ready undone */
	if (sock->sk->sk_data_ready == rds_tcp_listen_data_ready)
	sock->sk->sk_data_ready = sock->sk->sk_user_data;

	tc->t_sock = sock;
	tc->conn = conn;
	tc->t_orig_data_ready = sock->sk->sk_data_ready;
	tc->t_orig_write_space = sock->sk->sk_write_space;
	tc->t_orig_state_change = sock->sk->sk_state_change;

	sock->sk->sk_user_data = conn;
	sock->sk->sk_data_ready = rds_tcp_data_ready;
	sock->sk->sk_write_space = rds_tcp_write_space;
	sock->sk->sk_state_change = rds_tcp_state_change;

	write_unlock_bh(&sock->sk->sk_callback_lock);
	}

	static void rds_tcp_tc_info(struct socket *sock, unsigned int len,
	struct rds_info_iterator *iter,
	struct rds_info_lengths *lens)
	{
	struct rds_info_tcp_socket tsinfo;
	struct rds_tcp_connection *tc;
	unsigned long flags;
	struct sockaddr_in sin;
	int sinlen;

	spin_lock_irqsave(&rds_tcp_tc_list_lock, flags);

	if (len / sizeof(tsinfo) < rds_tcp_tc_count)
	goto out;

	list_for_each_entry(tc, &rds_tcp_tc_list, t_list_item) {

	sock->ops->getname(sock, (struct sockaddr *)&sin, &sinlen, 0);
	tsinfo.local_addr = sin.sin_addr.s_addr;
	tsinfo.local_port = sin.sin_port;
	sock->ops->getname(sock, (struct sockaddr *)&sin, &sinlen, 1);
	tsinfo.peer_addr = sin.sin_addr.s_addr;
	tsinfo.peer_port = sin.sin_port;

	tsinfo.hdr_rem = tc->t_tinc_hdr_rem;
	tsinfo.data_rem = tc->t_tinc_data_rem;
	tsinfo.last_sent_nxt = tc->t_last_sent_nxt;
	tsinfo.last_expected_una = tc->t_last_expected_una;
	tsinfo.last_seen_una = tc->t_last_seen_una;

	rds_info_copy(iter, &tsinfo, sizeof(tsinfo));
	}

	out:
	lens->nr = rds_tcp_tc_count;
	lens->each = sizeof(tsinfo);

	spin_unlock_irqrestore(&rds_tcp_tc_list_lock, flags);
	}

	static int rds_tcp_laddr_check(__be32 addr)
	{
	if (inet_addr_type(&init_net, addr) == RTN_LOCAL)
	return 0;
	return -EADDRNOTAVAIL;
	}

	static int rds_tcp_conn_alloc(struct rds_connection *conn, gfp_t gfp)
	{
	struct rds_tcp_connection *tc;

	tc = kmem_cache_alloc(rds_tcp_conn_slab, gfp);
	if (!tc)
	return -ENOMEM;

	tc->t_sock = NULL;
	tc->t_tinc = NULL;
	tc->t_tinc_hdr_rem = sizeof(struct rds_header);
	tc->t_tinc_data_rem = 0;

	conn->c_transport_data = tc;

	spin_lock_irq(&rds_tcp_conn_lock);
	list_add_tail(&tc->t_tcp_node, &rds_tcp_conn_list);
	spin_unlock_irq(&rds_tcp_conn_lock);

	rdsdebug("alloced tc %p\n", conn->c_transport_data);
	return 0;
	}

	static void rds_tcp_conn_free(void *arg)
	{
	struct rds_tcp_connection *tc = arg;
	unsigned long flags;
	rdsdebug("freeing tc %p\n", tc);

	spin_lock_irqsave(&rds_tcp_conn_lock, flags);
	list_del(&tc->t_tcp_node);
	spin_unlock_irqrestore(&rds_tcp_conn_lock, flags);

	kmem_cache_free(rds_tcp_conn_slab, tc);
	}

	static void rds_tcp_destroy_conns(void)
	{
	struct rds_tcp_connection tc, _tc;
	LIST_HEAD(tmp_list);

	/* avoid calling conn_destroy with irqs off */
	spin_lock_irq(&rds_tcp_conn_lock);
	list_splice(&rds_tcp_conn_list, &tmp_list);
	INIT_LIST_HEAD(&rds_tcp_conn_list);
	spin_unlock_irq(&rds_tcp_conn_lock);

	list_for_each_entry_safe(tc, _tc, &tmp_list, t_tcp_node) {
	if (tc->conn->c_passive)
	rds_conn_destroy(tc->conn->c_passive);
	rds_conn_destroy(tc->conn);
	}
	}

	static void rds_tcp_exit(void)
	{
	rds_info_deregister_func(RDS_INFO_TCP_SOCKETS, rds_tcp_tc_info);
	rds_tcp_listen_stop();
	rds_tcp_destroy_conns();
	rds_trans_unregister(&rds_tcp_transport);
	rds_tcp_recv_exit();
	kmem_cache_destroy(rds_tcp_conn_slab);
	}
	module_exit(rds_tcp_exit);

	struct rds_transport rds_tcp_transport = {
	.laddr_check = rds_tcp_laddr_check,
	.xmit_prepare = rds_tcp_xmit_prepare,
	.xmit_complete = rds_tcp_xmit_complete,
	.xmit = rds_tcp_xmit,
	.recv = rds_tcp_recv,
	.conn_alloc = rds_tcp_conn_alloc,
	.conn_free = rds_tcp_conn_free,
	.conn_connect = rds_tcp_conn_connect,
	.conn_shutdown = rds_tcp_conn_shutdown,
	.inc_copy_to_user = rds_tcp_inc_copy_to_user,
	.inc_free = rds_tcp_inc_free,
	.stats_info_copy = rds_tcp_stats_info_copy,
	.exit = rds_tcp_exit,
	.t_owner = THIS_MODULE,
	.t_name = "tcp",
	.t_type = RDS_TRANS_TCP,
	.t_prefer_loopback = 1,
	};

	static int rds_tcp_init(void)
	{
	int ret;

	rds_tcp_conn_slab = kmem_cache_create("rds_tcp_connection",
	sizeof(struct rds_tcp_connection),
	0, 0, NULL);
	if (!rds_tcp_conn_slab) {
	ret = -ENOMEM;
	goto out;
	}

	ret = rds_tcp_recv_init();
	if (ret)
	goto out_slab;

	ret = rds_trans_register(&rds_tcp_transport);
	if (ret)
	goto out_recv;

	ret = rds_tcp_listen_init();
	if (ret)
	goto out_register;

	rds_info_register_func(RDS_INFO_TCP_SOCKETS, rds_tcp_tc_info);

	goto out;

	out_register:
	rds_trans_unregister(&rds_tcp_transport);
	out_recv:
	rds_tcp_recv_exit();
	out_slab:
	kmem_cache_destroy(rds_tcp_conn_slab);
	out:
	return ret;
	}
	module_init(rds_tcp_init);

	MODULE_AUTHOR("Oracle Corporation <rds-devel@oss.oracle.com>");
	MODULE_DESCRIPTION("RDS: TCP transport");
	MODULE_LICENSE("Dual BSD/GPL");