net/rds/rdma_transport.c

   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 <linux/module.h>
  34 #include <rdma/rdma_cm.h>
  35
  36 #include "rdma_transport.h"
  37 #include "ib.h"
  38
  39 static struct rdma_cm_id *rds_rdma_listen_id;
  40
  41 int rds_rdma_cm_event_handler(struct rdma_cm_id *cm_id,
  42                               struct rdma_cm_event *event)
  43 {
  44         /* this can be null in the listening path */
  45         struct rds_connection *conn = cm_id->context;
  46         struct rds_transport *trans;
  47         int ret = 0;
  48
  49         rdsdebug("conn %p id %p handling event %u (%s)\n", conn, cm_id,
  50                  event->event, rdma_event_msg(event->event));
  51
  52         if (cm_id->device->node_type == RDMA_NODE_RNIC)
  53                 trans = &rds_iw_transport;
  54         else
  55                 trans = &rds_ib_transport;
  56
  57         /* Prevent shutdown from tearing down the connection
  58          * while we're executing. */
  59         if (conn) {
  60                 mutex_lock(&conn->c_cm_lock);
  61
  62                 /* If the connection is being shut down, bail out
  63                  * right away. We return 0 so cm_id doesn't get
  64                  * destroyed prematurely */
  65                 if (rds_conn_state(conn) == RDS_CONN_DISCONNECTING) {
  66                         /* Reject incoming connections while we're tearing
  67                          * down an existing one. */
  68                         if (event->event == RDMA_CM_EVENT_CONNECT_REQUEST)
  69                                 ret = 1;
  70                         goto out;
  71                 }
  72         }
  73
  74         switch (event->event) {
  75         case RDMA_CM_EVENT_CONNECT_REQUEST:
  76                 ret = trans->cm_handle_connect(cm_id, event);
  77                 break;
  78
  79         case RDMA_CM_EVENT_ADDR_RESOLVED:
  80                 /* XXX do we need to clean up if this fails? */
  81                 ret = rdma_resolve_route(cm_id,
  82                                          RDS_RDMA_RESOLVE_TIMEOUT_MS);
  83                 break;
  84
  85         case RDMA_CM_EVENT_ROUTE_RESOLVED:
  86                 /* Connection could have been dropped so make sure the
  87                  * cm_id is valid before proceeding
  88                  */
  89                 if (conn) {
  90                         struct rds_ib_connection *ibic;
  91
  92                         ibic = conn->c_transport_data;
  93                         if (ibic && ibic->i_cm_id == cm_id)
  94                                 ret = trans->cm_initiate_connect(cm_id);
  95                         else
  96                                 rds_conn_drop(conn);
  97                 }
  98                 break;
  99
 100         case RDMA_CM_EVENT_ESTABLISHED:
 101                 trans->cm_connect_complete(conn, event);
 102                 break;
 103
 104         case RDMA_CM_EVENT_ADDR_ERROR:
 105         case RDMA_CM_EVENT_ROUTE_ERROR:
 106         case RDMA_CM_EVENT_CONNECT_ERROR:
 107         case RDMA_CM_EVENT_UNREACHABLE:
 108         case RDMA_CM_EVENT_REJECTED:
 109         case RDMA_CM_EVENT_DEVICE_REMOVAL:
 110         case RDMA_CM_EVENT_ADDR_CHANGE:
 111                 if (conn)
 112                         rds_conn_drop(conn);
 113                 break;
 114
 115         case RDMA_CM_EVENT_DISCONNECTED:
 116                 rdsdebug("DISCONNECT event - dropping connection "
 117                         "%pI4->%pI4\n", &conn->c_laddr,
 118                          &conn->c_faddr);
 119                 rds_conn_drop(conn);
 120                 break;
 121
 122         default:
 123                 /* things like device disconnect? */
 124                 printk(KERN_ERR "RDS: unknown event %u (%s)!\n",
 125                        event->event, rdma_event_msg(event->event));
 126                 break;
 127         }
 128
 129 out:
 130         if (conn)
 131                 mutex_unlock(&conn->c_cm_lock);
 132
 133         rdsdebug("id %p event %u (%s) handling ret %d\n", cm_id, event->event,
 134                  rdma_event_msg(event->event), ret);
 135
 136         return ret;
 137 }
 138
 139 static int rds_rdma_listen_init(void)
 140 {
 141         struct sockaddr_in sin;
 142         struct rdma_cm_id *cm_id;
 143         int ret;
 144
 145         cm_id = rdma_create_id(&init_net, rds_rdma_cm_event_handler, NULL,
 146                                RDMA_PS_TCP, IB_QPT_RC);
 147         if (IS_ERR(cm_id)) {
 148                 ret = PTR_ERR(cm_id);
 149                 printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
 150                        "rdma_create_id() returned %d\n", ret);
 151                 return ret;
 152         }
 153
 154         sin.sin_family = AF_INET;
 155         sin.sin_addr.s_addr = (__force u32)htonl(INADDR_ANY);
 156         sin.sin_port = (__force u16)htons(RDS_PORT);
 157
 158         /*
 159          * XXX I bet this binds the cm_id to a device.  If we want to support
 160          * fail-over we'll have to take this into consideration.
 161          */
 162         ret = rdma_bind_addr(cm_id, (struct sockaddr *)&sin);
 163         if (ret) {
 164                 printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
 165                        "rdma_bind_addr() returned %d\n", ret);
 166                 goto out;
 167         }
 168
 169         ret = rdma_listen(cm_id, 128);
 170         if (ret) {
 171                 printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
 172                        "rdma_listen() returned %d\n", ret);
 173                 goto out;
 174         }
 175
 176         rdsdebug("cm %p listening on port %u\n", cm_id, RDS_PORT);
 177
 178         rds_rdma_listen_id = cm_id;
 179         cm_id = NULL;
 180 out:
 181         if (cm_id)
 182                 rdma_destroy_id(cm_id);
 183         return ret;
 184 }
 185
 186 static void rds_rdma_listen_stop(void)
 187 {
 188         if (rds_rdma_listen_id) {
 189                 rdsdebug("cm %p\n", rds_rdma_listen_id);
 190                 rdma_destroy_id(rds_rdma_listen_id);
 191                 rds_rdma_listen_id = NULL;
 192         }
 193 }
 194
 195 static int rds_rdma_init(void)
 196 {
 197         int ret;
 198
 199         ret = rds_rdma_listen_init();
 200         if (ret)
 201                 goto out;
 202
 203         ret = rds_iw_init();
 204         if (ret)
 205                 goto err_iw_init;
 206
 207         ret = rds_ib_init();
 208         if (ret)
 209                 goto err_ib_init;
 210
 211         goto out;
 212
 213 err_ib_init:
 214         rds_iw_exit();
 215 err_iw_init:
 216         rds_rdma_listen_stop();
 217 out:
 218         return ret;
 219 }
 220 module_init(rds_rdma_init);
 221
 222 static void rds_rdma_exit(void)
 223 {
 224         /* stop listening first to ensure no new connections are attempted */
 225         rds_rdma_listen_stop();
 226         rds_ib_exit();
 227         rds_iw_exit();
 228 }
 229 module_exit(rds_rdma_exit);
 230
 231 MODULE_AUTHOR("Oracle Corporation <rds-devel@oss.oracle.com>");
 232 MODULE_DESCRIPTION("RDS: IB/iWARP transport");
 233 MODULE_LICENSE("Dual BSD/GPL");
 234