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

 /*
  * Copyright (c) 2009, 2018 Oracle and/or its affiliates. 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/module.h>
 #include <rdma/rdma_cm.h>

 #include "rds_single_path.h"
 #include "rdma_transport.h"
 #include "ib.h"

 /* Global IPv4 and IPv6 RDS RDMA listener cm_id */
 static struct rdma_cm_id *rds_rdma_listen_id;
 #if IS_ENABLED(CONFIG_IPV6)
 static struct rdma_cm_id *rds6_rdma_listen_id;
 #endif

 /* Per IB specification 7.7.3, service level is a 4-bit field. */
 #define TOS_TO_SL(tos)		((tos) & 0xF)

 static int rds_rdma_cm_event_handler_cmn(struct rdma_cm_id *cm_id,
 					 struct rdma_cm_event *event,
 					 bool isv6)
 {
 	/* this can be null in the listening path */
 	struct rds_connection *conn = cm_id->context;
 	struct rds_transport *trans;
 	int ret = 0;
 	int *err;
 	u8 len;

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

 	if (cm_id->device->node_type == RDMA_NODE_IB_CA)
 		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, isv6);
 		break;

 	case RDMA_CM_EVENT_ADDR_RESOLVED:
 		rdma_set_service_type(cm_id, conn->c_tos);
 		rdma_set_min_rnr_timer(cm_id, IB_RNR_TIMER_000_32);
 		/* 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:
 		/* Connection could have been dropped so make sure the
 		 * cm_id is valid before proceeding
 		 */
 		if (conn) {
 			struct rds_ib_connection *ibic;

 			ibic = conn->c_transport_data;
 			if (ibic && ibic->i_cm_id == cm_id) {
 				cm_id->route.path_rec[0].sl =
 					TOS_TO_SL(conn->c_tos);
 				ret = trans->cm_initiate_connect(cm_id, isv6);
 			} else {
 				rds_conn_drop(conn);
 			}
 		}
 		break;

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

 	case RDMA_CM_EVENT_REJECTED:
 		if (!conn)
 			break;
 		err = (int *)rdma_consumer_reject_data(cm_id, event, &len);
 		if (!err ||
 		    (err && len >= sizeof(*err) &&
 		     ((*err) <= RDS_RDMA_REJ_INCOMPAT))) {
 			pr_warn("RDS/RDMA: conn <%pI6c, %pI6c> rejected, dropping connection\n",
 				&conn->c_laddr, &conn->c_faddr);

 			if (!conn->c_tos)
 				conn->c_proposed_version = RDS_PROTOCOL_COMPAT_VERSION;

 			rds_conn_drop(conn);
 		}
 		rdsdebug("Connection rejected: %s\n",
 			 rdma_reject_msg(cm_id, event->status));
 		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_DEVICE_REMOVAL:
 	case RDMA_CM_EVENT_ADDR_CHANGE:
 		if (conn)
 			rds_conn_drop(conn);
 		break;

 	case RDMA_CM_EVENT_DISCONNECTED:
 		if (!conn)
 			break;
 		rdsdebug("DISCONNECT event - dropping connection "
 			 "%pI6c->%pI6c\n", &conn->c_laddr,
 			 &conn->c_faddr);
 		rds_conn_drop(conn);
 		break;

 	case RDMA_CM_EVENT_TIMEWAIT_EXIT:
 		if (conn) {
 			pr_info("RDS: RDMA_CM_EVENT_TIMEWAIT_EXIT event: dropping connection %pI6c->%pI6c\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, rdma_event_msg(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,
 		 rdma_event_msg(event->event), ret);

 	return ret;
 }

 int rds_rdma_cm_event_handler(struct rdma_cm_id *cm_id,
 			      struct rdma_cm_event *event)
 {
 	return rds_rdma_cm_event_handler_cmn(cm_id, event, false);
 }

 #if IS_ENABLED(CONFIG_IPV6)
 int rds6_rdma_cm_event_handler(struct rdma_cm_id *cm_id,
 			       struct rdma_cm_event *event)
 {
 	return rds_rdma_cm_event_handler_cmn(cm_id, event, true);
 }
 #endif

 static int rds_rdma_listen_init_common(rdma_cm_event_handler handler,
 				       struct sockaddr *sa,
 				       struct rdma_cm_id **ret_cm_id)
 {
 	struct rdma_cm_id *cm_id;
 	int ret;

 	cm_id = rdma_create_id(&init_net, 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;
 	}

 	/*
 	 * 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, sa);
 	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);

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

 /* Initialize the RDS RDMA listeners.  We create two listeners for
  * compatibility reason.  The one on RDS_PORT is used for IPv4
  * requests only.  The one on RDS_CM_PORT is used for IPv6 requests
  * only.  So only IPv6 enabled RDS module will communicate using this
  * port.
  */
 static int rds_rdma_listen_init(void)
 {
 	int ret;
 #if IS_ENABLED(CONFIG_IPV6)
 	struct sockaddr_in6 sin6;
 #endif
 	struct sockaddr_in sin;

 	sin.sin_family = PF_INET;
 	sin.sin_addr.s_addr = htonl(INADDR_ANY);
 	sin.sin_port = htons(RDS_PORT);
 	ret = rds_rdma_listen_init_common(rds_rdma_cm_event_handler,
 					  (struct sockaddr *)&sin,
 					  &rds_rdma_listen_id);
 	if (ret != 0)
 		return ret;

 #if IS_ENABLED(CONFIG_IPV6)
 	sin6.sin6_family = PF_INET6;
 	sin6.sin6_addr = in6addr_any;
 	sin6.sin6_port = htons(RDS_CM_PORT);
 	sin6.sin6_scope_id = 0;
 	sin6.sin6_flowinfo = 0;
 	ret = rds_rdma_listen_init_common(rds6_rdma_cm_event_handler,
 					  (struct sockaddr *)&sin6,
 					  &rds6_rdma_listen_id);
 	/* Keep going even when IPv6 is not enabled in the system. */
 	if (ret != 0)
 		rdsdebug("Cannot set up IPv6 RDMA listener\n");
 #endif
 	return 0;
 }

 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;
 	}
 #if IS_ENABLED(CONFIG_IPV6)
 	if (rds6_rdma_listen_id) {
 		rdsdebug("cm %p\n", rds6_rdma_listen_id);
 		rdma_destroy_id(rds6_rdma_listen_id);
 		rds6_rdma_listen_id = NULL;
 	}
 #endif
 }

 static int rds_rdma_init(void)
 {
 	int ret;

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

 	ret = rds_rdma_listen_init();
 	if (ret)
 		rds_ib_exit();
 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();
 }
 module_exit(rds_rdma_exit);

 MODULE_AUTHOR("Oracle Corporation <rds-devel@oss.oracle.com>");
 MODULE_DESCRIPTION("RDS: IB transport");
 MODULE_LICENSE("Dual BSD/GPL");
	/*
	* Copyright (c) 2009, 2018 Oracle and/or its affiliates. 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/module.h>
	#include <rdma/rdma_cm.h>

	#include "rds_single_path.h"
	#include "rdma_transport.h"
	#include "ib.h"

	/* Global IPv4 and IPv6 RDS RDMA listener cm_id */
	static struct rdma_cm_id *rds_rdma_listen_id;
	#if IS_ENABLED(CONFIG_IPV6)
	static struct rdma_cm_id *rds6_rdma_listen_id;
	#endif

	/* Per IB specification 7.7.3, service level is a 4-bit field. */
	#define TOS_TO_SL(tos) ((tos) & 0xF)

	static int rds_rdma_cm_event_handler_cmn(struct rdma_cm_id *cm_id,
	struct rdma_cm_event *event,
	bool isv6)
	{
	/* this can be null in the listening path */
	struct rds_connection *conn = cm_id->context;
	struct rds_transport *trans;
	int ret = 0;
	int *err;
	u8 len;

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

	if (cm_id->device->node_type == RDMA_NODE_IB_CA)
	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, isv6);
	break;

	case RDMA_CM_EVENT_ADDR_RESOLVED:
	rdma_set_service_type(cm_id, conn->c_tos);
	rdma_set_min_rnr_timer(cm_id, IB_RNR_TIMER_000_32);
	/* 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:
	/* Connection could have been dropped so make sure the
	* cm_id is valid before proceeding
	*/
	if (conn) {
	struct rds_ib_connection *ibic;

	ibic = conn->c_transport_data;
	if (ibic && ibic->i_cm_id == cm_id) {
	cm_id->route.path_rec[0].sl =
	TOS_TO_SL(conn->c_tos);
	ret = trans->cm_initiate_connect(cm_id, isv6);
	} else {
	rds_conn_drop(conn);
	}
	}
	break;

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

	case RDMA_CM_EVENT_REJECTED:
	if (!conn)
	break;
	err = (int *)rdma_consumer_reject_data(cm_id, event, &len);
	if (!err \|\|
	(err && len >= sizeof(*err) &&
	((*err) <= RDS_RDMA_REJ_INCOMPAT))) {
	pr_warn("RDS/RDMA: conn <%pI6c, %pI6c> rejected, dropping connection\n",
	&conn->c_laddr, &conn->c_faddr);

	if (!conn->c_tos)
	conn->c_proposed_version = RDS_PROTOCOL_COMPAT_VERSION;

	rds_conn_drop(conn);
	}
	rdsdebug("Connection rejected: %s\n",
	rdma_reject_msg(cm_id, event->status));
	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_DEVICE_REMOVAL:
	case RDMA_CM_EVENT_ADDR_CHANGE:
	if (conn)
	rds_conn_drop(conn);
	break;

	case RDMA_CM_EVENT_DISCONNECTED:
	if (!conn)
	break;
	rdsdebug("DISCONNECT event - dropping connection "
	"%pI6c->%pI6c\n", &conn->c_laddr,
	&conn->c_faddr);
	rds_conn_drop(conn);
	break;

	case RDMA_CM_EVENT_TIMEWAIT_EXIT:
	if (conn) {
	pr_info("RDS: RDMA_CM_EVENT_TIMEWAIT_EXIT event: dropping connection %pI6c->%pI6c\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, rdma_event_msg(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,
	rdma_event_msg(event->event), ret);

	return ret;
	}

	int rds_rdma_cm_event_handler(struct rdma_cm_id *cm_id,
	struct rdma_cm_event *event)
	{
	return rds_rdma_cm_event_handler_cmn(cm_id, event, false);
	}

	#if IS_ENABLED(CONFIG_IPV6)
	int rds6_rdma_cm_event_handler(struct rdma_cm_id *cm_id,
	struct rdma_cm_event *event)
	{
	return rds_rdma_cm_event_handler_cmn(cm_id, event, true);
	}
	#endif

	static int rds_rdma_listen_init_common(rdma_cm_event_handler handler,
	struct sockaddr *sa,
	struct rdma_cm_id **ret_cm_id)
	{
	struct rdma_cm_id *cm_id;
	int ret;

	cm_id = rdma_create_id(&init_net, 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;
	}

	/*
	* 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, sa);
	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);

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

	/* Initialize the RDS RDMA listeners. We create two listeners for
	* compatibility reason. The one on RDS_PORT is used for IPv4
	* requests only. The one on RDS_CM_PORT is used for IPv6 requests
	* only. So only IPv6 enabled RDS module will communicate using this
	* port.
	*/
	static int rds_rdma_listen_init(void)
	{
	int ret;
	#if IS_ENABLED(CONFIG_IPV6)
	struct sockaddr_in6 sin6;
	#endif
	struct sockaddr_in sin;

	sin.sin_family = PF_INET;
	sin.sin_addr.s_addr = htonl(INADDR_ANY);
	sin.sin_port = htons(RDS_PORT);
	ret = rds_rdma_listen_init_common(rds_rdma_cm_event_handler,
	(struct sockaddr *)&sin,
	&rds_rdma_listen_id);
	if (ret != 0)
	return ret;

	#if IS_ENABLED(CONFIG_IPV6)
	sin6.sin6_family = PF_INET6;
	sin6.sin6_addr = in6addr_any;
	sin6.sin6_port = htons(RDS_CM_PORT);
	sin6.sin6_scope_id = 0;
	sin6.sin6_flowinfo = 0;
	ret = rds_rdma_listen_init_common(rds6_rdma_cm_event_handler,
	(struct sockaddr *)&sin6,
	&rds6_rdma_listen_id);
	/* Keep going even when IPv6 is not enabled in the system. */
	if (ret != 0)
	rdsdebug("Cannot set up IPv6 RDMA listener\n");
	#endif
	return 0;
	}

	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;
	}
	#if IS_ENABLED(CONFIG_IPV6)
	if (rds6_rdma_listen_id) {
	rdsdebug("cm %p\n", rds6_rdma_listen_id);
	rdma_destroy_id(rds6_rdma_listen_id);
	rds6_rdma_listen_id = NULL;
	}
	#endif
	}

	static int rds_rdma_init(void)
	{
	int ret;

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

	ret = rds_rdma_listen_init();
	if (ret)
	rds_ib_exit();
	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();
	}
	module_exit(rds_rdma_exit);

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