https://github.com/torvalds/linux
Tip revision: 6f7da290413ba713f0cdd9ff1a2a9bb129ef4f6c authored by Linus Torvalds on 02 July 2017, 23:07:02 UTC
Linux 4.12
Linux 4.12
Tip revision: 6f7da29
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 <linux/module.h>
#include <rdma/rdma_cm.h>
#include "rds_single_path.h"
#include "rdma_transport.h"
#include "ib.h"
static struct rdma_cm_id *rds_rdma_listen_id;
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, 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);
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:
/* 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)
ret = trans->cm_initiate_connect(cm_id);
else
rds_conn_drop(conn);
}
break;
case RDMA_CM_EVENT_ESTABLISHED:
trans->cm_connect_complete(conn, event);
break;
case RDMA_CM_EVENT_REJECTED:
rdsdebug("Connection rejected: %s\n",
rdma_reject_msg(cm_id, event->status));
/* FALLTHROUGH */
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:
rdsdebug("DISCONNECT event - dropping connection "
"%pI4->%pI4\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 %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, 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;
}
static int rds_rdma_listen_init(void)
{
struct sockaddr_in sin;
struct rdma_cm_id *cm_id;
int ret;
cm_id = rdma_create_id(&init_net, 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_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");