[mirror_ubuntu-artful-kernel.git] / net / rds / rdma_transport.c

/*
 * Copyright (c) 2009 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 <rdma/rdma_cm.h>

#include "rdma_transport.h"

static struct rdma_cm_id *rds_rdma_listen_id;

static char *rds_cm_event_strings[] = {
#define RDS_CM_EVENT_STRING(foo) \
		[RDMA_CM_EVENT_##foo] = __stringify(RDMA_CM_EVENT_##foo)
	RDS_CM_EVENT_STRING(ADDR_RESOLVED),
	RDS_CM_EVENT_STRING(ADDR_ERROR),
	RDS_CM_EVENT_STRING(ROUTE_RESOLVED),
	RDS_CM_EVENT_STRING(ROUTE_ERROR),
	RDS_CM_EVENT_STRING(CONNECT_REQUEST),
	RDS_CM_EVENT_STRING(CONNECT_RESPONSE),
	RDS_CM_EVENT_STRING(CONNECT_ERROR),
	RDS_CM_EVENT_STRING(UNREACHABLE),
	RDS_CM_EVENT_STRING(REJECTED),
	RDS_CM_EVENT_STRING(ESTABLISHED),
	RDS_CM_EVENT_STRING(DISCONNECTED),
	RDS_CM_EVENT_STRING(DEVICE_REMOVAL),
	RDS_CM_EVENT_STRING(MULTICAST_JOIN),
	RDS_CM_EVENT_STRING(MULTICAST_ERROR),
	RDS_CM_EVENT_STRING(ADDR_CHANGE),
	RDS_CM_EVENT_STRING(TIMEWAIT_EXIT),
#undef RDS_CM_EVENT_STRING
};

static char *rds_cm_event_str(enum rdma_cm_event_type type)
{
	return rds_str_array(rds_cm_event_strings,
			     ARRAY_SIZE(rds_cm_event_strings), type);
};

int rds_rdma_cm_event_handler(struct rdma_cm_id *cm_id,
			      struct rdma_cm_event *event)
{
	/* this can be null in the listening path */
	struct rds_connection *conn = cm_id->context;
	struct rds_transport *trans;
	int ret = 0;

	rdsdebug("conn %p id %p handling event %u (%s)\n", conn, cm_id,
		 event->event, rds_cm_event_str(event->event));

	if (cm_id->device->node_type == RDMA_NODE_RNIC)
		trans = &rds_iw_transport;
	else
		trans = &rds_ib_transport;

	/* Prevent shutdown from tearing down the connection
	 * while we're executing. */
	if (conn) {
		mutex_lock(&conn->c_cm_lock);

		/* If the connection is being shut down, bail out
		 * right away. We return 0 so cm_id doesn't get
		 * destroyed prematurely */
		if (rds_conn_state(conn) == RDS_CONN_DISCONNECTING) {
			/* Reject incoming connections while we're tearing
			 * down an existing one. */
			if (event->event == RDMA_CM_EVENT_CONNECT_REQUEST)
				ret = 1;
			goto out;
		}
	}

	switch (event->event) {
	case RDMA_CM_EVENT_CONNECT_REQUEST:
		ret = trans->cm_handle_connect(cm_id, event);
		break;

	case RDMA_CM_EVENT_ADDR_RESOLVED:
		/* XXX do we need to clean up if this fails? */
		ret = rdma_resolve_route(cm_id,
					 RDS_RDMA_RESOLVE_TIMEOUT_MS);
		break;

	case RDMA_CM_EVENT_ROUTE_RESOLVED:
		/* XXX worry about racing with listen acceptance */
		ret = trans->cm_initiate_connect(cm_id);
		break;

	case RDMA_CM_EVENT_ESTABLISHED:
		trans->cm_connect_complete(conn, event);
		break;

	case RDMA_CM_EVENT_ADDR_ERROR:
	case RDMA_CM_EVENT_ROUTE_ERROR:
	case RDMA_CM_EVENT_CONNECT_ERROR:
	case RDMA_CM_EVENT_UNREACHABLE:
	case RDMA_CM_EVENT_REJECTED:
	case RDMA_CM_EVENT_DEVICE_REMOVAL:
	case RDMA_CM_EVENT_ADDR_CHANGE:
		if (conn)
			rds_conn_drop(conn);
		break;

	case RDMA_CM_EVENT_DISCONNECTED:
		rdsdebug("DISCONNECT event - dropping connection "
			"%pI4->%pI4\n", &conn->c_laddr,
			 &conn->c_faddr);
		rds_conn_drop(conn);
		break;

	default:
		/* things like device disconnect? */
		printk(KERN_ERR "RDS: unknown event %u (%s)!\n",
		       event->event, rds_cm_event_str(event->event));
		break;
	}

out:
	if (conn)
		mutex_unlock(&conn->c_cm_lock);

	rdsdebug("id %p event %u (%s) handling ret %d\n", cm_id, event->event,
		 rds_cm_event_str(event->event), ret);

	return ret;
}

static int rds_rdma_listen_init(void)
{
	struct sockaddr_in sin;
	struct rdma_cm_id *cm_id;
	int ret;

	cm_id = rdma_create_id(rds_rdma_cm_event_handler, NULL, RDMA_PS_TCP,
			       IB_QPT_RC);
	if (IS_ERR(cm_id)) {
		ret = PTR_ERR(cm_id);
		printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
		       "rdma_create_id() returned %d\n", ret);
		return ret;
	}

	sin.sin_family = AF_INET,
	sin.sin_addr.s_addr = (__force u32)htonl(INADDR_ANY);
	sin.sin_port = (__force u16)htons(RDS_PORT);

	/*
	 * XXX I bet this binds the cm_id to a device.  If we want to support
	 * fail-over we'll have to take this into consideration.
	 */
	ret = rdma_bind_addr(cm_id, (struct sockaddr *)&sin);
	if (ret) {
		printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
		       "rdma_bind_addr() returned %d\n", ret);
		goto out;
	}

	ret = rdma_listen(cm_id, 128);
	if (ret) {
		printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
		       "rdma_listen() returned %d\n", ret);
		goto out;
	}

	rdsdebug("cm %p listening on port %u\n", cm_id, RDS_PORT);

	rds_rdma_listen_id = cm_id;
	cm_id = NULL;
out:
	if (cm_id)
		rdma_destroy_id(cm_id);
	return ret;
}

static void rds_rdma_listen_stop(void)
{
	if (rds_rdma_listen_id) {
		rdsdebug("cm %p\n", rds_rdma_listen_id);
		rdma_destroy_id(rds_rdma_listen_id);
		rds_rdma_listen_id = NULL;
	}
}

static int rds_rdma_init(void)
{
	int ret;

	ret = rds_rdma_listen_init();
	if (ret)
		goto out;

	ret = rds_iw_init();
	if (ret)
		goto err_iw_init;

	ret = rds_ib_init();
	if (ret)
		goto err_ib_init;

	goto out;

err_ib_init:
	rds_iw_exit();
err_iw_init:
	rds_rdma_listen_stop();
out:
	return ret;
}
module_init(rds_rdma_init);

static void rds_rdma_exit(void)
{
	/* stop listening first to ensure no new connections are attempted */
	rds_rdma_listen_stop();
	rds_ib_exit();
	rds_iw_exit();
}
module_exit(rds_rdma_exit);

MODULE_AUTHOR("Oracle Corporation <rds-devel@oss.oracle.com>");
MODULE_DESCRIPTION("RDS: IB/iWARP transport");
MODULE_LICENSE("Dual BSD/GPL");
Commit	Line	Data
55b7ed0b AG	1	/*
	2	* Copyright (c) 2009 Oracle. All rights reserved.
	3	*
	4	* This software is available to you under a choice of one of two
	5	* licenses. You may choose to be licensed under the terms of the GNU
	6	* General Public License (GPL) Version 2, available from the file
	7	* COPYING in the main directory of this source tree, or the
	8	* OpenIB.org BSD license below:
	9	*
	10	* Redistribution and use in source and binary forms, with or
	11	* without modification, are permitted provided that the following
	12	* conditions are met:
	13	*
	14	* - Redistributions of source code must retain the above
	15	* copyright notice, this list of conditions and the following
	16	* disclaimer.
	17	*
	18	* - Redistributions in binary form must reproduce the above
	19	* copyright notice, this list of conditions and the following
	20	* disclaimer in the documentation and/or other materials
	21	* provided with the distribution.
	22	*
	23	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	24	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	25	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	26	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	27	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	28	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	29	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	30	* SOFTWARE.
	31	*
	32	*/
	33	#include <rdma/rdma_cm.h>
	34
	35	#include "rdma_transport.h"
	36
11bc9421	37	static struct rdma_cm_id *rds_rdma_listen_id;
55b7ed0b	38
59f740a6 ZB	39	static char *rds_cm_event_strings[] = {
	40	#define RDS_CM_EVENT_STRING(foo) \
	41	[RDMA_CM_EVENT_##foo] = __stringify(RDMA_CM_EVENT_##foo)
	42	RDS_CM_EVENT_STRING(ADDR_RESOLVED),
	43	RDS_CM_EVENT_STRING(ADDR_ERROR),
	44	RDS_CM_EVENT_STRING(ROUTE_RESOLVED),
	45	RDS_CM_EVENT_STRING(ROUTE_ERROR),
	46	RDS_CM_EVENT_STRING(CONNECT_REQUEST),
	47	RDS_CM_EVENT_STRING(CONNECT_RESPONSE),
	48	RDS_CM_EVENT_STRING(CONNECT_ERROR),
	49	RDS_CM_EVENT_STRING(UNREACHABLE),
	50	RDS_CM_EVENT_STRING(REJECTED),
	51	RDS_CM_EVENT_STRING(ESTABLISHED),
	52	RDS_CM_EVENT_STRING(DISCONNECTED),
	53	RDS_CM_EVENT_STRING(DEVICE_REMOVAL),
	54	RDS_CM_EVENT_STRING(MULTICAST_JOIN),
	55	RDS_CM_EVENT_STRING(MULTICAST_ERROR),
	56	RDS_CM_EVENT_STRING(ADDR_CHANGE),
	57	RDS_CM_EVENT_STRING(TIMEWAIT_EXIT),
	58	#undef RDS_CM_EVENT_STRING
	59	};
	60
	61	static char *rds_cm_event_str(enum rdma_cm_event_type type)
	62	{
	63	return rds_str_array(rds_cm_event_strings,
	64	ARRAY_SIZE(rds_cm_event_strings), type);
	65	};
	66
55b7ed0b AG	67	int rds_rdma_cm_event_handler(struct rdma_cm_id *cm_id,
	68	struct rdma_cm_event *event)
	69	{
	70	/* this can be null in the listening path */
	71	struct rds_connection *conn = cm_id->context;
	72	struct rds_transport *trans;
	73	int ret = 0;
	74
59f740a6 ZB	75	rdsdebug("conn %p id %p handling event %u (%s)\n", conn, cm_id,
59f740a6 ZB	76	event->event, rds_cm_event_str(event->event));
55b7ed0b AG	77
	78	if (cm_id->device->node_type == RDMA_NODE_RNIC)
	79	trans = &rds_iw_transport;
	80	else
	81	trans = &rds_ib_transport;
	82
	83	/* Prevent shutdown from tearing down the connection
	84	* while we're executing. */
	85	if (conn) {
	86	mutex_lock(&conn->c_cm_lock);
	87
	88	/* If the connection is being shut down, bail out
	89	* right away. We return 0 so cm_id doesn't get
	90	* destroyed prematurely */
	91	if (rds_conn_state(conn) == RDS_CONN_DISCONNECTING) {
	92	/* Reject incoming connections while we're tearing
	93	* down an existing one. */
	94	if (event->event == RDMA_CM_EVENT_CONNECT_REQUEST)
	95	ret = 1;
	96	goto out;
	97	}
	98	}
	99
	100	switch (event->event) {
	101	case RDMA_CM_EVENT_CONNECT_REQUEST:
	102	ret = trans->cm_handle_connect(cm_id, event);
	103	break;
	104
	105	case RDMA_CM_EVENT_ADDR_RESOLVED:
	106	/* XXX do we need to clean up if this fails? */
	107	ret = rdma_resolve_route(cm_id,
	108	RDS_RDMA_RESOLVE_TIMEOUT_MS);
	109	break;
	110
	111	case RDMA_CM_EVENT_ROUTE_RESOLVED:
	112	/* XXX worry about racing with listen acceptance */
	113	ret = trans->cm_initiate_connect(cm_id);
	114	break;
	115
	116	case RDMA_CM_EVENT_ESTABLISHED:
	117	trans->cm_connect_complete(conn, event);
	118	break;
	119
	120	case RDMA_CM_EVENT_ADDR_ERROR:
	121	case RDMA_CM_EVENT_ROUTE_ERROR:
	122	case RDMA_CM_EVENT_CONNECT_ERROR:
	123	case RDMA_CM_EVENT_UNREACHABLE:
	124	case RDMA_CM_EVENT_REJECTED:
	125	case RDMA_CM_EVENT_DEVICE_REMOVAL:
	126	case RDMA_CM_EVENT_ADDR_CHANGE:
	127	if (conn)
	128	rds_conn_drop(conn);
	129	break;
	130
	131	case RDMA_CM_EVENT_DISCONNECTED:
97069788	132	rdsdebug("DISCONNECT event - dropping connection "
55b7ed0b AG	133	"%pI4->%pI4\n", &conn->c_laddr,
	134	&conn->c_faddr);
	135	rds_conn_drop(conn);
	136	break;
	137
	138	default:
	139	/* things like device disconnect? */
59f740a6 ZB	140	printk(KERN_ERR "RDS: unknown event %u (%s)!\n",
59f740a6 ZB	141	event->event, rds_cm_event_str(event->event));
55b7ed0b AG	142	break;
	143	}
	144
	145	out:
	146	if (conn)
	147	mutex_unlock(&conn->c_cm_lock);
	148
59f740a6 ZB	149	rdsdebug("id %p event %u (%s) handling ret %d\n", cm_id, event->event,
59f740a6 ZB	150	rds_cm_event_str(event->event), ret);
55b7ed0b AG	151
	152	return ret;
	153	}
	154
ef87b7ea	155	static int rds_rdma_listen_init(void)
55b7ed0b AG	156	{
	157	struct sockaddr_in sin;
	158	struct rdma_cm_id *cm_id;
	159	int ret;
	160
b26f9b99 SH	161	cm_id = rdma_create_id(rds_rdma_cm_event_handler, NULL, RDMA_PS_TCP,
b26f9b99 SH	162	IB_QPT_RC);
55b7ed0b AG	163	if (IS_ERR(cm_id)) {
55b7ed0b AG	164	ret = PTR_ERR(cm_id);
92c330b9	165	printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
55b7ed0b	166	"rdma_create_id() returned %d\n", ret);
24acc689	167	return ret;
55b7ed0b AG	168	}
55b7ed0b AG	169
3d7ddd54	170	sin.sin_family = AF_INET,
55b7ed0b AG	171	sin.sin_addr.s_addr = (__force u32)htonl(INADDR_ANY);
	172	sin.sin_port = (__force u16)htons(RDS_PORT);
	173
	174	/*
	175	* XXX I bet this binds the cm_id to a device. If we want to support
	176	* fail-over we'll have to take this into consideration.
	177	*/
	178	ret = rdma_bind_addr(cm_id, (struct sockaddr *)&sin);
	179	if (ret) {
92c330b9	180	printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
55b7ed0b AG	181	"rdma_bind_addr() returned %d\n", ret);
	182	goto out;
	183	}
	184
	185	ret = rdma_listen(cm_id, 128);
	186	if (ret) {
92c330b9	187	printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
55b7ed0b AG	188	"rdma_listen() returned %d\n", ret);
	189	goto out;
	190	}
	191
	192	rdsdebug("cm %p listening on port %u\n", cm_id, RDS_PORT);
	193
11bc9421	194	rds_rdma_listen_id = cm_id;
55b7ed0b AG	195	cm_id = NULL;
	196	out:
	197	if (cm_id)
	198	rdma_destroy_id(cm_id);
	199	return ret;
	200	}
	201
	202	static void rds_rdma_listen_stop(void)
	203	{
11bc9421 AG	204	if (rds_rdma_listen_id) {
	205	rdsdebug("cm %p\n", rds_rdma_listen_id);
	206	rdma_destroy_id(rds_rdma_listen_id);
	207	rds_rdma_listen_id = NULL;
55b7ed0b AG	208	}
	209	}
	210
ff51bf84	211	static int rds_rdma_init(void)
55b7ed0b AG	212	{
	213	int ret;
	214
	215	ret = rds_rdma_listen_init();
	216	if (ret)
	217	goto out;
	218
	219	ret = rds_iw_init();
	220	if (ret)
	221	goto err_iw_init;
	222
	223	ret = rds_ib_init();
	224	if (ret)
	225	goto err_ib_init;
	226
	227	goto out;
	228
	229	err_ib_init:
	230	rds_iw_exit();
	231	err_iw_init:
	232	rds_rdma_listen_stop();
	233	out:
	234	return ret;
	235	}
40d86609	236	module_init(rds_rdma_init);
55b7ed0b	237
ff51bf84	238	static void rds_rdma_exit(void)
55b7ed0b AG	239	{
	240	/* stop listening first to ensure no new connections are attempted */
	241	rds_rdma_listen_stop();
	242	rds_ib_exit();
	243	rds_iw_exit();
	244	}
40d86609 AG	245	module_exit(rds_rdma_exit);
	246
	247	MODULE_AUTHOR("Oracle Corporation <rds-devel@oss.oracle.com>");
	248	MODULE_DESCRIPTION("RDS: IB/iWARP transport");
	249	MODULE_LICENSE("Dual BSD/GPL");
55b7ed0b	250