LXR linux/net/rds/rdma

   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
  37static struct rdma_cm_id *rds_rdma_listen_id;
  38
  39int rds_rdma_cm_event_handler(struct rdma_cm_id *cm_id,
  40                              struct rdma_cm_event *event)
  41{
  42        /* this can be null in the listening path */
  43        struct rds_connection *conn = cm_id->context;
  44        struct rds_transport *trans;
  45        int ret = 0;
  46
  47        rdsdebug("conn %p id %p handling event %u\n", conn, cm_id,
  48                 event->event);
  49
  50        if (cm_id->device->node_type == RDMA_NODE_RNIC)
  51                trans = &rds_iw_transport;
  52        else
  53                trans = &rds_ib_transport;
  54
  55        /* Prevent shutdown from tearing down the connection
  56         * while we're executing. */
  57        if (conn) {
  58                mutex_lock(&conn->c_cm_lock);
  59
  60                /* If the connection is being shut down, bail out
  61                 * right away. We return 0 so cm_id doesn't get
  62                 * destroyed prematurely */
  63                if (rds_conn_state(conn) == RDS_CONN_DISCONNECTING) {
  64                        /* Reject incoming connections while we're tearing
  65                         * down an existing one. */
  66                        if (event->event == RDMA_CM_EVENT_CONNECT_REQUEST)
  67                                ret = 1;
  68                        goto out;
  69                }
  70        }
  71
  72        switch (event->event) {
  73        case RDMA_CM_EVENT_CONNECT_REQUEST:
  74                ret = trans->cm_handle_connect(cm_id, event);
  75                break;
  76
  77        case RDMA_CM_EVENT_ADDR_RESOLVED:
  78                /* XXX do we need to clean up if this fails? */
  79                ret = rdma_resolve_route(cm_id,
  80                                         RDS_RDMA_RESOLVE_TIMEOUT_MS);
  81                break;
  82
  83        case RDMA_CM_EVENT_ROUTE_RESOLVED:
  84                /* XXX worry about racing with listen acceptance */
  85                ret = trans->cm_initiate_connect(cm_id);
  86                break;
  87
  88        case RDMA_CM_EVENT_ESTABLISHED:
  89                trans->cm_connect_complete(conn, event);
  90                break;
  91
  92        case RDMA_CM_EVENT_ADDR_ERROR:
  93        case RDMA_CM_EVENT_ROUTE_ERROR:
  94        case RDMA_CM_EVENT_CONNECT_ERROR:
  95        case RDMA_CM_EVENT_UNREACHABLE:
  96        case RDMA_CM_EVENT_REJECTED:
  97        case RDMA_CM_EVENT_DEVICE_REMOVAL:
  98        case RDMA_CM_EVENT_ADDR_CHANGE:
  99                if (conn)
 100                        rds_conn_drop(conn);
 101                break;
 102
 103        case RDMA_CM_EVENT_DISCONNECTED:
 104                printk(KERN_WARNING "RDS/RDMA: DISCONNECT event - dropping connection "
 105                        "%pI4->%pI4\n", &conn->c_laddr,
 106                         &conn->c_faddr);
 107                rds_conn_drop(conn);
 108                break;
 109
 110        default:
 111                /* things like device disconnect? */
 112                printk(KERN_ERR "unknown event %u\n", event->event);
 113                BUG();
 114                break;
 115        }
 116
 117out:
 118        if (conn)
 119                mutex_unlock(&conn->c_cm_lock);
 120
 121        rdsdebug("id %p event %u handling ret %d\n", cm_id, event->event, ret);
 122
 123        return ret;
 124}
 125
 126static int __init rds_rdma_listen_init(void)
 127{
 128        struct sockaddr_in sin;
 129        struct rdma_cm_id *cm_id;
 130        int ret;
 131
 132        cm_id = rdma_create_id(rds_rdma_cm_event_handler, NULL, RDMA_PS_TCP);
 133        if (IS_ERR(cm_id)) {
 134                ret = PTR_ERR(cm_id);
 135                printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
 136                       "rdma_create_id() returned %d\n", ret);
 137                goto out;
 138        }
 139
 140        sin.sin_family = AF_INET,
 141        sin.sin_addr.s_addr = (__force u32)htonl(INADDR_ANY);
 142        sin.sin_port = (__force u16)htons(RDS_PORT);
 143
 144        /*
 145         * XXX I bet this binds the cm_id to a device.  If we want to support
 146         * fail-over we'll have to take this into consideration.
 147         */
 148        ret = rdma_bind_addr(cm_id, (struct sockaddr *)&sin);
 149        if (ret) {
 150                printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
 151                       "rdma_bind_addr() returned %d\n", ret);
 152                goto out;
 153        }
 154
 155        ret = rdma_listen(cm_id, 128);
 156        if (ret) {
 157                printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
 158                       "rdma_listen() returned %d\n", ret);
 159                goto out;
 160        }
 161
 162        rdsdebug("cm %p listening on port %u\n", cm_id, RDS_PORT);
 163
 164        rds_rdma_listen_id = cm_id;
 165        cm_id = NULL;
 166out:
 167        if (cm_id)
 168                rdma_destroy_id(cm_id);
 169        return ret;
 170}
 171
 172static void rds_rdma_listen_stop(void)
 173{
 174        if (rds_rdma_listen_id) {
 175                rdsdebug("cm %p\n", rds_rdma_listen_id);
 176                rdma_destroy_id(rds_rdma_listen_id);
 177                rds_rdma_listen_id = NULL;
 178        }
 179}
 180
 181int __init rds_rdma_init(void)
 182{
 183        int ret;
 184
 185        ret = rds_rdma_listen_init();
 186        if (ret)
 187                goto out;
 188
 189        ret = rds_iw_init();
 190        if (ret)
 191                goto err_iw_init;
 192
 193        ret = rds_ib_init();
 194        if (ret)
 195                goto err_ib_init;
 196
 197        goto out;
 198
 199err_ib_init:
 200        rds_iw_exit();
 201err_iw_init:
 202        rds_rdma_listen_stop();
 203out:
 204        return ret;
 205}
 206module_init(rds_rdma_init);
 207
 208void rds_rdma_exit(void)
 209{
 210        /* stop listening first to ensure no new connections are attempted */
 211        rds_rdma_listen_stop();
 212        rds_ib_exit();
 213        rds_iw_exit();
 214}
 215module_exit(rds_rdma_exit);
 216
 217MODULE_AUTHOR("Oracle Corporation <rds-devel@oss.oracle.com>");
 218MODULE_DESCRIPTION("RDS: IB/iWARP transport");
 219MODULE_LICENSE("Dual BSD/GPL");
 220
 221