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
  39static char *rds_cm_event_strings[] = {
  40#define RDS_CM_EVENT_STRING(foo) \
  41                [RDMA_CM_EVENT_##foo] = __stringify(RDMA_CM_EVENT_##foo)
  42        RDS_CM_EVENT_STRING(ADDR_RESOLVED),
  43        RDS_CM_EVENT_STRING(ADDR_ERROR),
  44        RDS_CM_EVENT_STRING(ROUTE_RESOLVED),
  45        RDS_CM_EVENT_STRING(ROUTE_ERROR),
  46        RDS_CM_EVENT_STRING(CONNECT_REQUEST),
  47        RDS_CM_EVENT_STRING(CONNECT_RESPONSE),
  48        RDS_CM_EVENT_STRING(CONNECT_ERROR),
  49        RDS_CM_EVENT_STRING(UNREACHABLE),
  50        RDS_CM_EVENT_STRING(REJECTED),
  51        RDS_CM_EVENT_STRING(ESTABLISHED),
  52        RDS_CM_EVENT_STRING(DISCONNECTED),
  53        RDS_CM_EVENT_STRING(DEVICE_REMOVAL),
  54        RDS_CM_EVENT_STRING(MULTICAST_JOIN),
  55        RDS_CM_EVENT_STRING(MULTICAST_ERROR),
  56        RDS_CM_EVENT_STRING(ADDR_CHANGE),
  57        RDS_CM_EVENT_STRING(TIMEWAIT_EXIT),
  58#undef RDS_CM_EVENT_STRING
  59};
  60
  61static char *rds_cm_event_str(enum rdma_cm_event_type type)
  62{
  63        return rds_str_array(rds_cm_event_strings,
  64                             ARRAY_SIZE(rds_cm_event_strings), type);
  65};
  66
  67int rds_rdma_cm_event_handler(struct rdma_cm_id *cm_id,
  68                              struct rdma_cm_event *event)
  69{
  70        /* this can be null in the listening path */
  71        struct rds_connection *conn = cm_id->context;
  72        struct rds_transport *trans;
  73        int ret = 0;
  74
  75        rdsdebug("conn %p id %p handling event %u (%s)\n", conn, cm_id,
  76                 event->event, rds_cm_event_str(event->event));
  77
  78        if (cm_id->device->node_type == RDMA_NODE_RNIC)
  79                trans = &rds_iw_transport;
  80        else
  81                trans = &rds_ib_transport;
  82
  83        /* Prevent shutdown from tearing down the connection
  84         * while we're executing. */
  85        if (conn) {
  86                mutex_lock(&conn->c_cm_lock);
  87
  88                /* If the connection is being shut down, bail out
  89                 * right away. We return 0 so cm_id doesn't get
  90                 * destroyed prematurely */
  91                if (rds_conn_state(conn) == RDS_CONN_DISCONNECTING) {
  92                        /* Reject incoming connections while we're tearing
  93                         * down an existing one. */
  94                        if (event->event == RDMA_CM_EVENT_CONNECT_REQUEST)
  95                                ret = 1;
  96                        goto out;
  97                }
  98        }
  99
 100        switch (event->event) {
 101        case RDMA_CM_EVENT_CONNECT_REQUEST:
 102                ret = trans->cm_handle_connect(cm_id, event);
 103                break;
 104
 105        case RDMA_CM_EVENT_ADDR_RESOLVED:
 106                /* XXX do we need to clean up if this fails? */
 107                ret = rdma_resolve_route(cm_id,
 108                                         RDS_RDMA_RESOLVE_TIMEOUT_MS);
 109                break;
 110
 111        case RDMA_CM_EVENT_ROUTE_RESOLVED:
 112                /* XXX worry about racing with listen acceptance */
 113                ret = trans->cm_initiate_connect(cm_id);
 114                break;
 115
 116        case RDMA_CM_EVENT_ESTABLISHED:
 117                trans->cm_connect_complete(conn, event);
 118                break;
 119
 120        case RDMA_CM_EVENT_ADDR_ERROR:
 121        case RDMA_CM_EVENT_ROUTE_ERROR:
 122        case RDMA_CM_EVENT_CONNECT_ERROR:
 123        case RDMA_CM_EVENT_UNREACHABLE:
 124        case RDMA_CM_EVENT_REJECTED:
 125        case RDMA_CM_EVENT_DEVICE_REMOVAL:
 126        case RDMA_CM_EVENT_ADDR_CHANGE:
 127                if (conn)
 128                        rds_conn_drop(conn);
 129                break;
 130
 131        case RDMA_CM_EVENT_DISCONNECTED:
 132                rdsdebug("DISCONNECT event - dropping connection "
 133                        "%pI4->%pI4\n", &conn->c_laddr,
 134                         &conn->c_faddr);
 135                rds_conn_drop(conn);
 136                break;
 137
 138        default:
 139                /* things like device disconnect? */
 140                printk(KERN_ERR "RDS: unknown event %u (%s)!\n",
 141                       event->event, rds_cm_event_str(event->event));
 142                break;
 143        }
 144
 145out:
 146        if (conn)
 147                mutex_unlock(&conn->c_cm_lock);
 148
 149        rdsdebug("id %p event %u (%s) handling ret %d\n", cm_id, event->event,
 150                 rds_cm_event_str(event->event), ret);
 151
 152        return ret;
 153}
 154
 155static int rds_rdma_listen_init(void)
 156{
 157        struct sockaddr_in sin;
 158        struct rdma_cm_id *cm_id;
 159        int ret;
 160
 161        cm_id = rdma_create_id(rds_rdma_cm_event_handler, NULL, RDMA_PS_TCP);
 162        if (IS_ERR(cm_id)) {
 163                ret = PTR_ERR(cm_id);
 164                printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
 165                       "rdma_create_id() returned %d\n", ret);
 166                return ret;
 167        }
 168
 169        sin.sin_family = AF_INET,
 170        sin.sin_addr.s_addr = (__force u32)htonl(INADDR_ANY);
 171        sin.sin_port = (__force u16)htons(RDS_PORT);
 172
 173        /*
 174         * XXX I bet this binds the cm_id to a device.  If we want to support
 175         * fail-over we'll have to take this into consideration.
 176         */
 177        ret = rdma_bind_addr(cm_id, (struct sockaddr *)&sin);
 178        if (ret) {
 179                printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
 180                       "rdma_bind_addr() returned %d\n", ret);
 181                goto out;
 182        }
 183
 184        ret = rdma_listen(cm_id, 128);
 185        if (ret) {
 186                printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
 187                       "rdma_listen() returned %d\n", ret);
 188                goto out;
 189        }
 190
 191        rdsdebug("cm %p listening on port %u\n", cm_id, RDS_PORT);
 192
 193        rds_rdma_listen_id = cm_id;
 194        cm_id = NULL;
 195out:
 196        if (cm_id)
 197                rdma_destroy_id(cm_id);
 198        return ret;
 199}
 200
 201static void rds_rdma_listen_stop(void)
 202{
 203        if (rds_rdma_listen_id) {
 204                rdsdebug("cm %p\n", rds_rdma_listen_id);
 205                rdma_destroy_id(rds_rdma_listen_id);
 206                rds_rdma_listen_id = NULL;
 207        }
 208}
 209
 210static int rds_rdma_init(void)
 211{
 212        int ret;
 213
 214        ret = rds_rdma_listen_init();
 215        if (ret)
 216                goto out;
 217
 218        ret = rds_iw_init();
 219        if (ret)
 220                goto err_iw_init;
 221
 222        ret = rds_ib_init();
 223        if (ret)
 224                goto err_ib_init;
 225
 226        goto out;
 227
 228err_ib_init:
 229        rds_iw_exit();
 230err_iw_init:
 231        rds_rdma_listen_stop();
 232out:
 233        return ret;
 234}
 235module_init(rds_rdma_init);
 236
 237static void rds_rdma_exit(void)
 238{
 239        /* stop listening first to ensure no new connections are attempted */
 240        rds_rdma_listen_stop();
 241        rds_ib_exit();
 242        rds_iw_exit();
 243}
 244module_exit(rds_rdma_exit);
 245
 246MODULE_AUTHOR("Oracle Corporation <rds-devel@oss.oracle.com>");
 247MODULE_DESCRIPTION("RDS: IB/iWARP transport");
 248MODULE_LICENSE("Dual BSD/GPL");
 249
 250