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