SAFE public projects git trees. - safe/jmp/linux-2.6/blob - drivers/scsi/scsi_transport_iscsi.c

   1 /*
   2  * iSCSI transport class definitions
   3  *
   4  * Copyright (C) IBM Corporation, 2004
   5  * Copyright (C) Mike Christie, 2004 - 2005
   6  * Copyright (C) Dmitry Yusupov, 2004 - 2005
   7  * Copyright (C) Alex Aizman, 2004 - 2005
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  22  */
  23 #include <linux/module.h>
  24 #include <linux/mutex.h>
  25 #include <net/tcp.h>
  26 #include <scsi/scsi.h>
  27 #include <scsi/scsi_host.h>
  28 #include <scsi/scsi_device.h>
  29 #include <scsi/scsi_transport.h>
  30 #include <scsi/scsi_transport_iscsi.h>
  31 #include <scsi/iscsi_if.h>
  32
  33 #define ISCSI_SESSION_ATTRS 19
  34 #define ISCSI_CONN_ATTRS 13
  35 #define ISCSI_HOST_ATTRS 4
  36 #define ISCSI_TRANSPORT_VERSION "2.0-869"
  37
  38 struct iscsi_internal {
  39         int daemon_pid;
  40         struct scsi_transport_template t;
  41         struct iscsi_transport *iscsi_transport;
  42         struct list_head list;
  43         struct device dev;
  44
  45         struct device_attribute *host_attrs[ISCSI_HOST_ATTRS + 1];
  46         struct transport_container conn_cont;
  47         struct device_attribute *conn_attrs[ISCSI_CONN_ATTRS + 1];
  48         struct transport_container session_cont;
  49         struct device_attribute *session_attrs[ISCSI_SESSION_ATTRS + 1];
  50 };
  51
  52 static atomic_t iscsi_session_nr; /* sysfs session id for next new session */
  53 static struct workqueue_struct *iscsi_eh_timer_workq;
  54
  55 /*
  56  * list of registered transports and lock that must
  57  * be held while accessing list. The iscsi_transport_lock must
  58  * be acquired after the rx_queue_mutex.
  59  */
  60 static LIST_HEAD(iscsi_transports);
  61 static DEFINE_SPINLOCK(iscsi_transport_lock);
  62
  63 #define to_iscsi_internal(tmpl) \
  64         container_of(tmpl, struct iscsi_internal, t)
  65
  66 #define dev_to_iscsi_internal(_dev) \
  67         container_of(_dev, struct iscsi_internal, dev)
  68
  69 static void iscsi_transport_release(struct device *dev)
  70 {
  71         struct iscsi_internal *priv = dev_to_iscsi_internal(dev);
  72         kfree(priv);
  73 }
  74
  75 /*
  76  * iscsi_transport_class represents the iscsi_transports that are
  77  * registered.
  78  */
  79 static struct class iscsi_transport_class = {
  80         .name = "iscsi_transport",
  81         .dev_release = iscsi_transport_release,
  82 };
  83
  84 static ssize_t
  85 show_transport_handle(struct device *dev, struct device_attribute *attr,
  86                       char *buf)
  87 {
  88         struct iscsi_internal *priv = dev_to_iscsi_internal(dev);
  89         return sprintf(buf, "%llu\n", (unsigned long long)iscsi_handle(priv->iscsi_transport));
  90 }
  91 static DEVICE_ATTR(handle, S_IRUGO, show_transport_handle, NULL);
  92
  93 #define show_transport_attr(name, format)                               \
  94 static ssize_t                                                          \
  95 show_transport_##name(struct device *dev,                               \
  96                       struct device_attribute *attr,char *buf)          \
  97 {                                                                       \
  98         struct iscsi_internal *priv = dev_to_iscsi_internal(dev);       \
  99         return sprintf(buf, format"\n", priv->iscsi_transport->name);   \
 100 }                                                                       \
 101 static DEVICE_ATTR(name, S_IRUGO, show_transport_##name, NULL);
 102
 103 show_transport_attr(caps, "0x%x");
 104
 105 static struct attribute *iscsi_transport_attrs[] = {
 106         &dev_attr_handle.attr,
 107         &dev_attr_caps.attr,
 108         NULL,
 109 };
 110
 111 static struct attribute_group iscsi_transport_group = {
 112         .attrs = iscsi_transport_attrs,
 113 };
 114
 115 static int iscsi_setup_host(struct transport_container *tc, struct device *dev,
 116                             struct device *cdev)
 117 {
 118         struct Scsi_Host *shost = dev_to_shost(dev);
 119         struct iscsi_cls_host *ihost = shost->shost_data;
 120
 121         memset(ihost, 0, sizeof(*ihost));
 122         INIT_LIST_HEAD(&ihost->sessions);
 123         mutex_init(&ihost->mutex);
 124         atomic_set(&ihost->nr_scans, 0);
 125
 126         snprintf(ihost->scan_workq_name, KOBJ_NAME_LEN, "iscsi_scan_%d",
 127                 shost->host_no);
 128         ihost->scan_workq = create_singlethread_workqueue(
 129                                                 ihost->scan_workq_name);
 130         if (!ihost->scan_workq)
 131                 return -ENOMEM;
 132         return 0;
 133 }
 134
 135 static int iscsi_remove_host(struct transport_container *tc, struct device *dev,
 136                              struct device *cdev)
 137 {
 138         struct Scsi_Host *shost = dev_to_shost(dev);
 139         struct iscsi_cls_host *ihost = shost->shost_data;
 140
 141         destroy_workqueue(ihost->scan_workq);
 142         return 0;
 143 }
 144
 145 static DECLARE_TRANSPORT_CLASS(iscsi_host_class,
 146                                "iscsi_host",
 147                                iscsi_setup_host,
 148                                iscsi_remove_host,
 149                                NULL);
 150
 151 static DECLARE_TRANSPORT_CLASS(iscsi_session_class,
 152                                "iscsi_session",
 153                                NULL,
 154                                NULL,
 155                                NULL);
 156
 157 static DECLARE_TRANSPORT_CLASS(iscsi_connection_class,
 158                                "iscsi_connection",
 159                                NULL,
 160                                NULL,
 161                                NULL);
 162
 163 static struct sock *nls;
 164 static DEFINE_MUTEX(rx_queue_mutex);
 165
 166 static LIST_HEAD(sesslist);
 167 static DEFINE_SPINLOCK(sesslock);
 168 static LIST_HEAD(connlist);
 169 static DEFINE_SPINLOCK(connlock);
 170
 171 static uint32_t iscsi_conn_get_sid(struct iscsi_cls_conn *conn)
 172 {
 173         struct iscsi_cls_session *sess = iscsi_dev_to_session(conn->dev.parent);
 174         return sess->sid;
 175 }
 176
 177 /*
 178  * Returns the matching session to a given sid
 179  */
 180 static struct iscsi_cls_session *iscsi_session_lookup(uint32_t sid)
 181 {
 182         unsigned long flags;
 183         struct iscsi_cls_session *sess;
 184
 185         spin_lock_irqsave(&sesslock, flags);
 186         list_for_each_entry(sess, &sesslist, sess_list) {
 187                 if (sess->sid == sid) {
 188                         spin_unlock_irqrestore(&sesslock, flags);
 189                         return sess;
 190                 }
 191         }
 192         spin_unlock_irqrestore(&sesslock, flags);
 193         return NULL;
 194 }
 195
 196 /*
 197  * Returns the matching connection to a given sid / cid tuple
 198  */
 199 static struct iscsi_cls_conn *iscsi_conn_lookup(uint32_t sid, uint32_t cid)
 200 {
 201         unsigned long flags;
 202         struct iscsi_cls_conn *conn;
 203
 204         spin_lock_irqsave(&connlock, flags);
 205         list_for_each_entry(conn, &connlist, conn_list) {
 206                 if ((conn->cid == cid) && (iscsi_conn_get_sid(conn) == sid)) {
 207                         spin_unlock_irqrestore(&connlock, flags);
 208                         return conn;
 209                 }
 210         }
 211         spin_unlock_irqrestore(&connlock, flags);
 212         return NULL;
 213 }
 214
 215 /*
 216  * The following functions can be used by LLDs that allocate
 217  * their own scsi_hosts or by software iscsi LLDs
 218  */
 219 static struct {
 220         int value;
 221         char *name;
 222 } iscsi_session_state_names[] = {
 223         { ISCSI_SESSION_LOGGED_IN,      "LOGGED_IN" },
 224         { ISCSI_SESSION_FAILED,         "FAILED" },
 225         { ISCSI_SESSION_FREE,           "FREE" },
 226 };
 227
 228 static const char *iscsi_session_state_name(int state)
 229 {
 230         int i;
 231         char *name = NULL;
 232
 233         for (i = 0; i < ARRAY_SIZE(iscsi_session_state_names); i++) {
 234                 if (iscsi_session_state_names[i].value == state) {
 235                         name = iscsi_session_state_names[i].name;
 236                         break;
 237                 }
 238         }
 239         return name;
 240 }
 241
 242 int iscsi_session_chkready(struct iscsi_cls_session *session)
 243 {
 244         unsigned long flags;
 245         int err;
 246
 247         spin_lock_irqsave(&session->lock, flags);
 248         switch (session->state) {
 249         case ISCSI_SESSION_LOGGED_IN:
 250                 err = 0;
 251                 break;
 252         case ISCSI_SESSION_FAILED:
 253                 err = DID_IMM_RETRY << 16;
 254                 break;
 255         case ISCSI_SESSION_FREE:
 256                 err = DID_NO_CONNECT << 16;
 257                 break;
 258         default:
 259                 err = DID_NO_CONNECT << 16;
 260                 break;
 261         }
 262         spin_unlock_irqrestore(&session->lock, flags);
 263         return err;
 264 }
 265 EXPORT_SYMBOL_GPL(iscsi_session_chkready);
 266
 267 static void iscsi_session_release(struct device *dev)
 268 {
 269         struct iscsi_cls_session *session = iscsi_dev_to_session(dev);
 270         struct Scsi_Host *shost;
 271
 272         shost = iscsi_session_to_shost(session);
 273         scsi_host_put(shost);
 274         kfree(session);
 275 }
 276
 277 static int iscsi_is_session_dev(const struct device *dev)
 278 {
 279         return dev->release == iscsi_session_release;
 280 }
 281
 282 /**
 283  * iscsi_scan_finished - helper to report when running scans are done
 284  * @shost: scsi host
 285  * @time: scan run time
 286  *
 287  * This function can be used by drives like qla4xxx to report to the scsi
 288  * layer when the scans it kicked off at module load time are done.
 289  */
 290 int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time)
 291 {
 292         struct iscsi_cls_host *ihost = shost->shost_data;
 293         /*
 294          * qla4xxx will have kicked off some session unblocks before calling
 295          * scsi_scan_host, so just wait for them to complete.
 296          */
 297         return !atomic_read(&ihost->nr_scans);
 298 }
 299 EXPORT_SYMBOL_GPL(iscsi_scan_finished);
 300
 301 static int iscsi_user_scan(struct Scsi_Host *shost, uint channel,
 302                            uint id, uint lun)
 303 {
 304         struct iscsi_cls_host *ihost = shost->shost_data;
 305         struct iscsi_cls_session *session;
 306
 307         mutex_lock(&ihost->mutex);
 308         list_for_each_entry(session, &ihost->sessions, host_list) {
 309                 if ((channel == SCAN_WILD_CARD || channel == 0) &&
 310                     (id == SCAN_WILD_CARD || id == session->target_id))
 311                         scsi_scan_target(&session->dev, 0,
 312                                          session->target_id, lun, 1);
 313         }
 314         mutex_unlock(&ihost->mutex);
 315
 316         return 0;
 317 }
 318
 319 static void iscsi_scan_session(struct work_struct *work)
 320 {
 321         struct iscsi_cls_session *session =
 322                         container_of(work, struct iscsi_cls_session, scan_work);
 323         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 324         struct iscsi_cls_host *ihost = shost->shost_data;
 325         unsigned long flags;
 326
 327         spin_lock_irqsave(&session->lock, flags);
 328         if (session->state != ISCSI_SESSION_LOGGED_IN) {
 329                 spin_unlock_irqrestore(&session->lock, flags);
 330                 goto done;
 331         }
 332         spin_unlock_irqrestore(&session->lock, flags);
 333
 334         scsi_scan_target(&session->dev, 0, session->target_id,
 335                          SCAN_WILD_CARD, 1);
 336 done:
 337         atomic_dec(&ihost->nr_scans);
 338 }
 339
 340 static void session_recovery_timedout(struct work_struct *work)
 341 {
 342         struct iscsi_cls_session *session =
 343                 container_of(work, struct iscsi_cls_session,
 344                              recovery_work.work);
 345         unsigned long flags;
 346
 347         iscsi_cls_session_printk(KERN_INFO, session,
 348                                  "session recovery timed out after %d secs\n",
 349                                  session->recovery_tmo);
 350
 351         spin_lock_irqsave(&session->lock, flags);
 352         switch (session->state) {
 353         case ISCSI_SESSION_FAILED:
 354                 session->state = ISCSI_SESSION_FREE;
 355                 break;
 356         case ISCSI_SESSION_LOGGED_IN:
 357         case ISCSI_SESSION_FREE:
 358                 /* we raced with the unblock's flush */
 359                 spin_unlock_irqrestore(&session->lock, flags);
 360                 return;
 361         }
 362         spin_unlock_irqrestore(&session->lock, flags);
 363
 364         if (session->transport->session_recovery_timedout)
 365                 session->transport->session_recovery_timedout(session);
 366
 367         scsi_target_unblock(&session->dev);
 368 }
 369
 370 static void __iscsi_unblock_session(struct work_struct *work)
 371 {
 372         struct iscsi_cls_session *session =
 373                         container_of(work, struct iscsi_cls_session,
 374                                      unblock_work);
 375         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 376         struct iscsi_cls_host *ihost = shost->shost_data;
 377         unsigned long flags;
 378
 379         /*
 380          * The recovery and unblock work get run from the same workqueue,
 381          * so try to cancel it if it was going to run after this unblock.
 382          */
 383         cancel_delayed_work(&session->recovery_work);
 384         spin_lock_irqsave(&session->lock, flags);
 385         session->state = ISCSI_SESSION_LOGGED_IN;
 386         spin_unlock_irqrestore(&session->lock, flags);
 387         /* start IO */
 388         scsi_target_unblock(&session->dev);
 389         /*
 390          * Only do kernel scanning if the driver is properly hooked into
 391          * the async scanning code (drivers like iscsi_tcp do login and
 392          * scanning from userspace).
 393          */
 394         if (shost->hostt->scan_finished) {
 395                 if (queue_work(ihost->scan_workq, &session->scan_work))
 396                         atomic_inc(&ihost->nr_scans);
 397         }
 398 }
 399
 400 /**
 401  * iscsi_unblock_session - set a session as logged in and start IO.
 402  * @session: iscsi session
 403  *
 404  * Mark a session as ready to accept IO.
 405  */
 406 void iscsi_unblock_session(struct iscsi_cls_session *session)
 407 {
 408         queue_work(iscsi_eh_timer_workq, &session->unblock_work);
 409         /*
 410          * make sure all the events have completed before tell the driver
 411          * it is safe
 412          */
 413         flush_workqueue(iscsi_eh_timer_workq);
 414 }
 415 EXPORT_SYMBOL_GPL(iscsi_unblock_session);
 416
 417 static void __iscsi_block_session(struct work_struct *work)
 418 {
 419         struct iscsi_cls_session *session =
 420                         container_of(work, struct iscsi_cls_session,
 421                                      block_work);
 422         unsigned long flags;
 423
 424         spin_lock_irqsave(&session->lock, flags);
 425         session->state = ISCSI_SESSION_FAILED;
 426         spin_unlock_irqrestore(&session->lock, flags);
 427         scsi_target_block(&session->dev);
 428         queue_delayed_work(iscsi_eh_timer_workq, &session->recovery_work,
 429                            session->recovery_tmo * HZ);
 430 }
 431
 432 void iscsi_block_session(struct iscsi_cls_session *session)
 433 {
 434         queue_work(iscsi_eh_timer_workq, &session->block_work);
 435 }
 436 EXPORT_SYMBOL_GPL(iscsi_block_session);
 437
 438 static void __iscsi_unbind_session(struct work_struct *work)
 439 {
 440         struct iscsi_cls_session *session =
 441                         container_of(work, struct iscsi_cls_session,
 442                                      unbind_work);
 443         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 444         struct iscsi_cls_host *ihost = shost->shost_data;
 445
 446         /* Prevent new scans and make sure scanning is not in progress */
 447         mutex_lock(&ihost->mutex);
 448         if (list_empty(&session->host_list)) {
 449                 mutex_unlock(&ihost->mutex);
 450                 return;
 451         }
 452         list_del_init(&session->host_list);
 453         mutex_unlock(&ihost->mutex);
 454
 455         scsi_remove_target(&session->dev);
 456         iscsi_session_event(session, ISCSI_KEVENT_UNBIND_SESSION);
 457 }
 458
 459 static int iscsi_unbind_session(struct iscsi_cls_session *session)
 460 {
 461         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 462         struct iscsi_cls_host *ihost = shost->shost_data;
 463
 464         return queue_work(ihost->scan_workq, &session->unbind_work);
 465 }
 466
 467 struct iscsi_cls_session *
 468 iscsi_alloc_session(struct Scsi_Host *shost,
 469                     struct iscsi_transport *transport)
 470 {
 471         struct iscsi_cls_session *session;
 472
 473         session = kzalloc(sizeof(*session) + transport->sessiondata_size,
 474                           GFP_KERNEL);
 475         if (!session)
 476                 return NULL;
 477
 478         session->transport = transport;
 479         session->recovery_tmo = 120;
 480         session->state = ISCSI_SESSION_FREE;
 481         INIT_DELAYED_WORK(&session->recovery_work, session_recovery_timedout);
 482         INIT_LIST_HEAD(&session->host_list);
 483         INIT_LIST_HEAD(&session->sess_list);
 484         INIT_WORK(&session->unblock_work, __iscsi_unblock_session);
 485         INIT_WORK(&session->block_work, __iscsi_block_session);
 486         INIT_WORK(&session->unbind_work, __iscsi_unbind_session);
 487         INIT_WORK(&session->scan_work, iscsi_scan_session);
 488         spin_lock_init(&session->lock);
 489
 490         /* this is released in the dev's release function */
 491         scsi_host_get(shost);
 492         session->dev.parent = &shost->shost_gendev;
 493         session->dev.release = iscsi_session_release;
 494         device_initialize(&session->dev);
 495         if (transport->sessiondata_size)
 496                 session->dd_data = &session[1];
 497         return session;
 498 }
 499 EXPORT_SYMBOL_GPL(iscsi_alloc_session);
 500
 501 int iscsi_add_session(struct iscsi_cls_session *session, unsigned int target_id)
 502 {
 503         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 504         struct iscsi_cls_host *ihost;
 505         unsigned long flags;
 506         int err;
 507
 508         ihost = shost->shost_data;
 509         session->sid = atomic_add_return(1, &iscsi_session_nr);
 510         session->target_id = target_id;
 511
 512         snprintf(session->dev.bus_id, BUS_ID_SIZE, "session%u",
 513                  session->sid);
 514         err = device_add(&session->dev);
 515         if (err) {
 516                 iscsi_cls_session_printk(KERN_ERR, session,
 517                                          "could not register session's dev\n");
 518                 goto release_host;
 519         }
 520         transport_register_device(&session->dev);
 521
 522         spin_lock_irqsave(&sesslock, flags);
 523         list_add(&session->sess_list, &sesslist);
 524         spin_unlock_irqrestore(&sesslock, flags);
 525
 526         mutex_lock(&ihost->mutex);
 527         list_add(&session->host_list, &ihost->sessions);
 528         mutex_unlock(&ihost->mutex);
 529
 530         iscsi_session_event(session, ISCSI_KEVENT_CREATE_SESSION);
 531         return 0;
 532
 533 release_host:
 534         scsi_host_put(shost);
 535         return err;
 536 }
 537 EXPORT_SYMBOL_GPL(iscsi_add_session);
 538
 539 /**
 540  * iscsi_create_session - create iscsi class session
 541  * @shost: scsi host
 542  * @transport: iscsi transport
 543  * @target_id: which target
 544  *
 545  * This can be called from a LLD or iscsi_transport.
 546  */
 547 struct iscsi_cls_session *
 548 iscsi_create_session(struct Scsi_Host *shost,
 549                      struct iscsi_transport *transport,
 550                      unsigned int target_id)
 551 {
 552         struct iscsi_cls_session *session;
 553
 554         session = iscsi_alloc_session(shost, transport);
 555         if (!session)
 556                 return NULL;
 557
 558         if (iscsi_add_session(session, target_id)) {
 559                 iscsi_free_session(session);
 560                 return NULL;
 561         }
 562         return session;
 563 }
 564 EXPORT_SYMBOL_GPL(iscsi_create_session);
 565
 566 static void iscsi_conn_release(struct device *dev)
 567 {
 568         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev);
 569         struct device *parent = conn->dev.parent;
 570
 571         kfree(conn);
 572         put_device(parent);
 573 }
 574
 575 static int iscsi_is_conn_dev(const struct device *dev)
 576 {
 577         return dev->release == iscsi_conn_release;
 578 }
 579
 580 static int iscsi_iter_destroy_conn_fn(struct device *dev, void *data)
 581 {
 582         if (!iscsi_is_conn_dev(dev))
 583                 return 0;
 584         return iscsi_destroy_conn(iscsi_dev_to_conn(dev));
 585 }
 586
 587 void iscsi_remove_session(struct iscsi_cls_session *session)
 588 {
 589         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 590         struct iscsi_cls_host *ihost = shost->shost_data;
 591         unsigned long flags;
 592         int err;
 593
 594         spin_lock_irqsave(&sesslock, flags);
 595         list_del(&session->sess_list);
 596         spin_unlock_irqrestore(&sesslock, flags);
 597
 598         /* make sure there are no blocks/unblocks queued */
 599         flush_workqueue(iscsi_eh_timer_workq);
 600         /* make sure the timedout callout is not running */
 601         if (!cancel_delayed_work(&session->recovery_work))
 602                 flush_workqueue(iscsi_eh_timer_workq);
 603         /*
 604          * If we are blocked let commands flow again. The lld or iscsi
 605          * layer should set up the queuecommand to fail commands.
 606          * We assume that LLD will not be calling block/unblock while
 607          * removing the session.
 608          */
 609         spin_lock_irqsave(&session->lock, flags);
 610         session->state = ISCSI_SESSION_FREE;
 611         spin_unlock_irqrestore(&session->lock, flags);
 612
 613         scsi_target_unblock(&session->dev);
 614         /* flush running scans then delete devices */
 615         flush_workqueue(ihost->scan_workq);
 616         __iscsi_unbind_session(&session->unbind_work);
 617
 618         /* hw iscsi may not have removed all connections from session */
 619         err = device_for_each_child(&session->dev, NULL,
 620                                     iscsi_iter_destroy_conn_fn);
 621         if (err)
 622                 iscsi_cls_session_printk(KERN_ERR, session,
 623                                          "Could not delete all connections "
 624                                          "for session. Error %d.\n", err);
 625
 626         transport_unregister_device(&session->dev);
 627         device_del(&session->dev);
 628 }
 629 EXPORT_SYMBOL_GPL(iscsi_remove_session);
 630
 631 void iscsi_free_session(struct iscsi_cls_session *session)
 632 {
 633         iscsi_session_event(session, ISCSI_KEVENT_DESTROY_SESSION);
 634         put_device(&session->dev);
 635 }
 636 EXPORT_SYMBOL_GPL(iscsi_free_session);
 637
 638 /**
 639  * iscsi_destroy_session - destroy iscsi session
 640  * @session: iscsi_session
 641  *
 642  * Can be called by a LLD or iscsi_transport. There must not be
 643  * any running connections.
 644  */
 645 int iscsi_destroy_session(struct iscsi_cls_session *session)
 646 {
 647         iscsi_remove_session(session);
 648         iscsi_free_session(session);
 649         return 0;
 650 }
 651 EXPORT_SYMBOL_GPL(iscsi_destroy_session);
 652
 653 /**
 654  * iscsi_create_conn - create iscsi class connection
 655  * @session: iscsi cls session
 656  * @cid: connection id
 657  *
 658  * This can be called from a LLD or iscsi_transport. The connection
 659  * is child of the session so cid must be unique for all connections
 660  * on the session.
 661  *
 662  * Since we do not support MCS, cid will normally be zero. In some cases
 663  * for software iscsi we could be trying to preallocate a connection struct
 664  * in which case there could be two connection structs and cid would be
 665  * non-zero.
 666  */
 667 struct iscsi_cls_conn *
 668 iscsi_create_conn(struct iscsi_cls_session *session, uint32_t cid)
 669 {
 670         struct iscsi_transport *transport = session->transport;
 671         struct iscsi_cls_conn *conn;
 672         unsigned long flags;
 673         int err;
 674
 675         conn = kzalloc(sizeof(*conn) + transport->conndata_size, GFP_KERNEL);
 676         if (!conn)
 677                 return NULL;
 678
 679         if (transport->conndata_size)
 680                 conn->dd_data = &conn[1];
 681
 682         INIT_LIST_HEAD(&conn->conn_list);
 683         conn->transport = transport;
 684         conn->cid = cid;
 685
 686         /* this is released in the dev's release function */
 687         if (!get_device(&session->dev))
 688                 goto free_conn;
 689
 690         snprintf(conn->dev.bus_id, BUS_ID_SIZE, "connection%d:%u",
 691                  session->sid, cid);
 692         conn->dev.parent = &session->dev;
 693         conn->dev.release = iscsi_conn_release;
 694         err = device_register(&conn->dev);
 695         if (err) {
 696                 iscsi_cls_session_printk(KERN_ERR, session, "could not "
 697                                          "register connection's dev\n");
 698                 goto release_parent_ref;
 699         }
 700         transport_register_device(&conn->dev);
 701
 702         spin_lock_irqsave(&connlock, flags);
 703         list_add(&conn->conn_list, &connlist);
 704         conn->active = 1;
 705         spin_unlock_irqrestore(&connlock, flags);
 706         return conn;
 707
 708 release_parent_ref:
 709         put_device(&session->dev);
 710 free_conn:
 711         kfree(conn);
 712         return NULL;
 713 }
 714
 715 EXPORT_SYMBOL_GPL(iscsi_create_conn);
 716
 717 /**
 718  * iscsi_destroy_conn - destroy iscsi class connection
 719  * @conn: iscsi cls session
 720  *
 721  * This can be called from a LLD or iscsi_transport.
 722  */
 723 int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
 724 {
 725         unsigned long flags;
 726
 727         spin_lock_irqsave(&connlock, flags);
 728         conn->active = 0;
 729         list_del(&conn->conn_list);
 730         spin_unlock_irqrestore(&connlock, flags);
 731
 732         transport_unregister_device(&conn->dev);
 733         device_unregister(&conn->dev);
 734         return 0;
 735 }
 736 EXPORT_SYMBOL_GPL(iscsi_destroy_conn);
 737
 738 /*
 739  * iscsi interface functions
 740  */
 741 static struct iscsi_internal *
 742 iscsi_if_transport_lookup(struct iscsi_transport *tt)
 743 {
 744         struct iscsi_internal *priv;
 745         unsigned long flags;
 746
 747         spin_lock_irqsave(&iscsi_transport_lock, flags);
 748         list_for_each_entry(priv, &iscsi_transports, list) {
 749                 if (tt == priv->iscsi_transport) {
 750                         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 751                         return priv;
 752                 }
 753         }
 754         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 755         return NULL;
 756 }
 757
 758 static int
 759 iscsi_broadcast_skb(struct sk_buff *skb, gfp_t gfp)
 760 {
 761         int rc;
 762
 763         rc = netlink_broadcast(nls, skb, 0, 1, gfp);
 764         if (rc < 0) {
 765                 printk(KERN_ERR "iscsi: can not broadcast skb (%d)\n", rc);
 766                 return rc;
 767         }
 768
 769         return 0;
 770 }
 771
 772 static int
 773 iscsi_unicast_skb(struct sk_buff *skb, int pid)
 774 {
 775         int rc;
 776
 777         rc = netlink_unicast(nls, skb, pid, MSG_DONTWAIT);
 778         if (rc < 0) {
 779                 printk(KERN_ERR "iscsi: can not unicast skb (%d)\n", rc);
 780                 return rc;
 781         }
 782
 783         return 0;
 784 }
 785
 786 int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
 787                    char *data, uint32_t data_size)
 788 {
 789         struct nlmsghdr *nlh;
 790         struct sk_buff *skb;
 791         struct iscsi_uevent *ev;
 792         char *pdu;
 793         struct iscsi_internal *priv;
 794         int len = NLMSG_SPACE(sizeof(*ev) + sizeof(struct iscsi_hdr) +
 795                               data_size);
 796
 797         priv = iscsi_if_transport_lookup(conn->transport);
 798         if (!priv)
 799                 return -EINVAL;
 800
 801         skb = alloc_skb(len, GFP_ATOMIC);
 802         if (!skb) {
 803                 iscsi_conn_error(conn, ISCSI_ERR_CONN_FAILED);
 804                 iscsi_cls_conn_printk(KERN_ERR, conn, "can not deliver "
 805                                       "control PDU: OOM\n");
 806                 return -ENOMEM;
 807         }
 808
 809         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
 810         ev = NLMSG_DATA(nlh);
 811         memset(ev, 0, sizeof(*ev));
 812         ev->transport_handle = iscsi_handle(conn->transport);
 813         ev->type = ISCSI_KEVENT_RECV_PDU;
 814         ev->r.recv_req.cid = conn->cid;
 815         ev->r.recv_req.sid = iscsi_conn_get_sid(conn);
 816         pdu = (char*)ev + sizeof(*ev);
 817         memcpy(pdu, hdr, sizeof(struct iscsi_hdr));
 818         memcpy(pdu + sizeof(struct iscsi_hdr), data, data_size);
 819
 820         return iscsi_unicast_skb(skb, priv->daemon_pid);
 821 }
 822 EXPORT_SYMBOL_GPL(iscsi_recv_pdu);
 823
 824 void iscsi_conn_error(struct iscsi_cls_conn *conn, enum iscsi_err error)
 825 {
 826         struct nlmsghdr *nlh;
 827         struct sk_buff  *skb;
 828         struct iscsi_uevent *ev;
 829         struct iscsi_internal *priv;
 830         int len = NLMSG_SPACE(sizeof(*ev));
 831
 832         priv = iscsi_if_transport_lookup(conn->transport);
 833         if (!priv)
 834                 return;
 835
 836         skb = alloc_skb(len, GFP_ATOMIC);
 837         if (!skb) {
 838                 iscsi_cls_conn_printk(KERN_ERR, conn, "gracefully ignored "
 839                                       "conn error (%d)\n", error);
 840                 return;
 841         }
 842
 843         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
 844         ev = NLMSG_DATA(nlh);
 845         ev->transport_handle = iscsi_handle(conn->transport);
 846         ev->type = ISCSI_KEVENT_CONN_ERROR;
 847         ev->r.connerror.error = error;
 848         ev->r.connerror.cid = conn->cid;
 849         ev->r.connerror.sid = iscsi_conn_get_sid(conn);
 850
 851         iscsi_broadcast_skb(skb, GFP_ATOMIC);
 852
 853         iscsi_cls_conn_printk(KERN_INFO, conn, "detected conn error (%d)\n",
 854                               error);
 855 }
 856 EXPORT_SYMBOL_GPL(iscsi_conn_error);
 857
 858 static int
 859 iscsi_if_send_reply(int pid, int seq, int type, int done, int multi,
 860                       void *payload, int size)
 861 {
 862         struct sk_buff  *skb;
 863         struct nlmsghdr *nlh;
 864         int len = NLMSG_SPACE(size);
 865         int flags = multi ? NLM_F_MULTI : 0;
 866         int t = done ? NLMSG_DONE : type;
 867
 868         skb = alloc_skb(len, GFP_ATOMIC);
 869         if (!skb) {
 870                 printk(KERN_ERR "Could not allocate skb to send reply.\n");
 871                 return -ENOMEM;
 872         }
 873
 874         nlh = __nlmsg_put(skb, pid, seq, t, (len - sizeof(*nlh)), 0);
 875         nlh->nlmsg_flags = flags;
 876         memcpy(NLMSG_DATA(nlh), payload, size);
 877         return iscsi_unicast_skb(skb, pid);
 878 }
 879
 880 static int
 881 iscsi_if_get_stats(struct iscsi_transport *transport, struct nlmsghdr *nlh)
 882 {
 883         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
 884         struct iscsi_stats *stats;
 885         struct sk_buff *skbstat;
 886         struct iscsi_cls_conn *conn;
 887         struct nlmsghdr *nlhstat;
 888         struct iscsi_uevent *evstat;
 889         struct iscsi_internal *priv;
 890         int len = NLMSG_SPACE(sizeof(*ev) +
 891                               sizeof(struct iscsi_stats) +
 892                               sizeof(struct iscsi_stats_custom) *
 893                               ISCSI_STATS_CUSTOM_MAX);
 894         int err = 0;
 895
 896         priv = iscsi_if_transport_lookup(transport);
 897         if (!priv)
 898                 return -EINVAL;
 899
 900         conn = iscsi_conn_lookup(ev->u.get_stats.sid, ev->u.get_stats.cid);
 901         if (!conn)
 902                 return -EEXIST;
 903
 904         do {
 905                 int actual_size;
 906
 907                 skbstat = alloc_skb(len, GFP_ATOMIC);
 908                 if (!skbstat) {
 909                         iscsi_cls_conn_printk(KERN_ERR, conn, "can not "
 910                                               "deliver stats: OOM\n");
 911                         return -ENOMEM;
 912                 }
 913
 914                 nlhstat = __nlmsg_put(skbstat, priv->daemon_pid, 0, 0,
 915                                       (len - sizeof(*nlhstat)), 0);
 916                 evstat = NLMSG_DATA(nlhstat);
 917                 memset(evstat, 0, sizeof(*evstat));
 918                 evstat->transport_handle = iscsi_handle(conn->transport);
 919                 evstat->type = nlh->nlmsg_type;
 920                 evstat->u.get_stats.cid =
 921                         ev->u.get_stats.cid;
 922                 evstat->u.get_stats.sid =
 923                         ev->u.get_stats.sid;
 924                 stats = (struct iscsi_stats *)
 925                         ((char*)evstat + sizeof(*evstat));
 926                 memset(stats, 0, sizeof(*stats));
 927
 928                 transport->get_stats(conn, stats);
 929                 actual_size = NLMSG_SPACE(sizeof(struct iscsi_uevent) +
 930                                           sizeof(struct iscsi_stats) +
 931                                           sizeof(struct iscsi_stats_custom) *
 932                                           stats->custom_length);
 933                 actual_size -= sizeof(*nlhstat);
 934                 actual_size = NLMSG_LENGTH(actual_size);
 935                 skb_trim(skbstat, NLMSG_ALIGN(actual_size));
 936                 nlhstat->nlmsg_len = actual_size;
 937
 938                 err = iscsi_unicast_skb(skbstat, priv->daemon_pid);
 939         } while (err < 0 && err != -ECONNREFUSED);
 940
 941         return err;
 942 }
 943
 944 /**
 945  * iscsi_session_event - send session destr. completion event
 946  * @session: iscsi class session
 947  * @event: type of event
 948  */
 949 int iscsi_session_event(struct iscsi_cls_session *session,
 950                         enum iscsi_uevent_e event)
 951 {
 952         struct iscsi_internal *priv;
 953         struct Scsi_Host *shost;
 954         struct iscsi_uevent *ev;
 955         struct sk_buff  *skb;
 956         struct nlmsghdr *nlh;
 957         int rc, len = NLMSG_SPACE(sizeof(*ev));
 958
 959         priv = iscsi_if_transport_lookup(session->transport);
 960         if (!priv)
 961                 return -EINVAL;
 962         shost = iscsi_session_to_shost(session);
 963
 964         skb = alloc_skb(len, GFP_KERNEL);
 965         if (!skb) {
 966                 iscsi_cls_session_printk(KERN_ERR, session,
 967                                          "Cannot notify userspace of session "
 968                                          "event %u\n", event);
 969                 return -ENOMEM;
 970         }
 971
 972         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
 973         ev = NLMSG_DATA(nlh);
 974         ev->transport_handle = iscsi_handle(session->transport);
 975
 976         ev->type = event;
 977         switch (event) {
 978         case ISCSI_KEVENT_DESTROY_SESSION:
 979                 ev->r.d_session.host_no = shost->host_no;
 980                 ev->r.d_session.sid = session->sid;
 981                 break;
 982         case ISCSI_KEVENT_CREATE_SESSION:
 983                 ev->r.c_session_ret.host_no = shost->host_no;
 984                 ev->r.c_session_ret.sid = session->sid;
 985                 break;
 986         case ISCSI_KEVENT_UNBIND_SESSION:
 987                 ev->r.unbind_session.host_no = shost->host_no;
 988                 ev->r.unbind_session.sid = session->sid;
 989                 break;
 990         default:
 991                 iscsi_cls_session_printk(KERN_ERR, session, "Invalid event "
 992                                          "%u.\n", event);
 993                 kfree_skb(skb);
 994                 return -EINVAL;
 995         }
 996
 997         /*
 998          * this will occur if the daemon is not up, so we just warn
 999          * the user and when the daemon is restarted it will handle it
1000          */
1001         rc = iscsi_broadcast_skb(skb, GFP_KERNEL);
1002         if (rc < 0)
1003                 iscsi_cls_session_printk(KERN_ERR, session,
1004                                          "Cannot notify userspace of session "
1005                                          "event %u. Check iscsi daemon\n",
1006                                          event);
1007         return rc;
1008 }
1009 EXPORT_SYMBOL_GPL(iscsi_session_event);
1010
1011 static int
1012 iscsi_if_create_session(struct iscsi_internal *priv, struct iscsi_uevent *ev,
1013                         uint32_t host_no, uint32_t initial_cmdsn,
1014                         uint16_t cmds_max, uint16_t queue_depth)
1015 {
1016         struct iscsi_transport *transport = priv->iscsi_transport;
1017         struct iscsi_cls_session *session;
1018         struct Scsi_Host *shost = NULL;
1019
1020         /*
1021          * Software iscsi allocates a host per session, but
1022          * offload drivers (and possibly iser one day) allocate a host per
1023          * hba/nic/rnic. Offload will match a host here, but software will
1024          * return a new hostno after the create_session callback has returned.
1025          */
1026         if (host_no != UINT_MAX) {
1027                 shost = scsi_host_lookup(host_no);
1028                 if (IS_ERR(shost)) {
1029                         printk(KERN_ERR "Could not find host no %u to "
1030                                "create session\n", host_no);
1031                         return -ENODEV;
1032                 }
1033         }
1034
1035         session = transport->create_session(shost, cmds_max, queue_depth,
1036                                             initial_cmdsn, &host_no);
1037         if (shost)
1038                 scsi_host_put(shost);
1039         if (!session)
1040                 return -ENOMEM;
1041
1042         ev->r.c_session_ret.host_no = host_no;
1043         ev->r.c_session_ret.sid = session->sid;
1044         return 0;
1045 }
1046
1047 static int
1048 iscsi_if_create_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1049 {
1050         struct iscsi_cls_conn *conn;
1051         struct iscsi_cls_session *session;
1052
1053         session = iscsi_session_lookup(ev->u.c_conn.sid);
1054         if (!session) {
1055                 printk(KERN_ERR "iscsi: invalid session %d.\n",
1056                        ev->u.c_conn.sid);
1057                 return -EINVAL;
1058         }
1059
1060         conn = transport->create_conn(session, ev->u.c_conn.cid);
1061         if (!conn) {
1062                 iscsi_cls_session_printk(KERN_ERR, session,
1063                                          "couldn't create a new connection.");
1064                 return -ENOMEM;
1065         }
1066
1067         ev->r.c_conn_ret.sid = session->sid;
1068         ev->r.c_conn_ret.cid = conn->cid;
1069         return 0;
1070 }
1071
1072 static int
1073 iscsi_if_destroy_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1074 {
1075         struct iscsi_cls_conn *conn;
1076
1077         conn = iscsi_conn_lookup(ev->u.d_conn.sid, ev->u.d_conn.cid);
1078         if (!conn)
1079                 return -EINVAL;
1080
1081         if (transport->destroy_conn)
1082                 transport->destroy_conn(conn);
1083         return 0;
1084 }
1085
1086 static int
1087 iscsi_set_param(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1088 {
1089         char *data = (char*)ev + sizeof(*ev);
1090         struct iscsi_cls_conn *conn;
1091         struct iscsi_cls_session *session;
1092         int err = 0, value = 0;
1093
1094         session = iscsi_session_lookup(ev->u.set_param.sid);
1095         conn = iscsi_conn_lookup(ev->u.set_param.sid, ev->u.set_param.cid);
1096         if (!conn || !session)
1097                 return -EINVAL;
1098
1099         switch (ev->u.set_param.param) {
1100         case ISCSI_PARAM_SESS_RECOVERY_TMO:
1101                 sscanf(data, "%d", &value);
1102                 if (value != 0)
1103                         session->recovery_tmo = value;
1104                 break;
1105         default:
1106                 err = transport->set_param(conn, ev->u.set_param.param,
1107                                            data, ev->u.set_param.len);
1108         }
1109
1110         return err;
1111 }
1112
1113 static int
1114 iscsi_if_transport_ep(struct iscsi_transport *transport,
1115                       struct iscsi_uevent *ev, int msg_type)
1116 {
1117         struct sockaddr *dst_addr;
1118         int rc = 0;
1119
1120         switch (msg_type) {
1121         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1122                 if (!transport->ep_connect)
1123                         return -EINVAL;
1124
1125                 dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1126                 rc = transport->ep_connect(dst_addr,
1127                                            ev->u.ep_connect.non_blocking,
1128                                            &ev->r.ep_connect_ret.handle);
1129                 break;
1130         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1131                 if (!transport->ep_poll)
1132                         return -EINVAL;
1133
1134                 ev->r.retcode = transport->ep_poll(ev->u.ep_poll.ep_handle,
1135                                                    ev->u.ep_poll.timeout_ms);
1136                 break;
1137         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1138                 if (!transport->ep_disconnect)
1139                         return -EINVAL;
1140
1141                 transport->ep_disconnect(ev->u.ep_disconnect.ep_handle);
1142                 break;
1143         }
1144         return rc;
1145 }
1146
1147 static int
1148 iscsi_tgt_dscvr(struct iscsi_transport *transport,
1149                 struct iscsi_uevent *ev)
1150 {
1151         struct Scsi_Host *shost;
1152         struct sockaddr *dst_addr;
1153         int err;
1154
1155         if (!transport->tgt_dscvr)
1156                 return -EINVAL;
1157
1158         shost = scsi_host_lookup(ev->u.tgt_dscvr.host_no);
1159         if (IS_ERR(shost)) {
1160                 printk(KERN_ERR "target discovery could not find host no %u\n",
1161                        ev->u.tgt_dscvr.host_no);
1162                 return -ENODEV;
1163         }
1164
1165
1166         dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1167         err = transport->tgt_dscvr(shost, ev->u.tgt_dscvr.type,
1168                                    ev->u.tgt_dscvr.enable, dst_addr);
1169         scsi_host_put(shost);
1170         return err;
1171 }
1172
1173 static int
1174 iscsi_set_host_param(struct iscsi_transport *transport,
1175                      struct iscsi_uevent *ev)
1176 {
1177         char *data = (char*)ev + sizeof(*ev);
1178         struct Scsi_Host *shost;
1179         int err;
1180
1181         if (!transport->set_host_param)
1182                 return -ENOSYS;
1183
1184         shost = scsi_host_lookup(ev->u.set_host_param.host_no);
1185         if (IS_ERR(shost)) {
1186                 printk(KERN_ERR "set_host_param could not find host no %u\n",
1187                        ev->u.set_host_param.host_no);
1188                 return -ENODEV;
1189         }
1190
1191         err = transport->set_host_param(shost, ev->u.set_host_param.param,
1192                                         data, ev->u.set_host_param.len);
1193         scsi_host_put(shost);
1194         return err;
1195 }
1196
1197 static int
1198 iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
1199 {
1200         int err = 0;
1201         uint32_t host_no = UINT_MAX;
1202         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1203         struct iscsi_transport *transport = NULL;
1204         struct iscsi_internal *priv;
1205         struct iscsi_cls_session *session;
1206         struct iscsi_cls_conn *conn;
1207
1208         priv = iscsi_if_transport_lookup(iscsi_ptr(ev->transport_handle));
1209         if (!priv)
1210                 return -EINVAL;
1211         transport = priv->iscsi_transport;
1212
1213         if (!try_module_get(transport->owner))
1214                 return -EINVAL;
1215
1216         priv->daemon_pid = NETLINK_CREDS(skb)->pid;
1217
1218         switch (nlh->nlmsg_type) {
1219         case ISCSI_UEVENT_CREATE_SESSION:
1220                 err = iscsi_if_create_session(priv, ev, host_no,
1221                                               ev->u.c_session.initial_cmdsn,
1222                                               ev->u.c_session.cmds_max,
1223                                               ev->u.c_session.queue_depth);
1224                 break;
1225         case ISCSI_UEVENT_CREATE_BOUND_SESSION:
1226                 err = iscsi_if_create_session(priv, ev,
1227                                         ev->u.c_bound_session.host_no,
1228                                         ev->u.c_bound_session.initial_cmdsn,
1229                                         ev->u.c_bound_session.cmds_max,
1230                                         ev->u.c_bound_session.queue_depth);
1231                 break;
1232         case ISCSI_UEVENT_DESTROY_SESSION:
1233                 session = iscsi_session_lookup(ev->u.d_session.sid);
1234                 if (session)
1235                         transport->destroy_session(session);
1236                 else
1237                         err = -EINVAL;
1238                 break;
1239         case ISCSI_UEVENT_UNBIND_SESSION:
1240                 session = iscsi_session_lookup(ev->u.d_session.sid);
1241                 if (session)
1242                         iscsi_unbind_session(session);
1243                 else
1244                         err = -EINVAL;
1245                 break;
1246         case ISCSI_UEVENT_CREATE_CONN:
1247                 err = iscsi_if_create_conn(transport, ev);
1248                 break;
1249         case ISCSI_UEVENT_DESTROY_CONN:
1250                 err = iscsi_if_destroy_conn(transport, ev);
1251                 break;
1252         case ISCSI_UEVENT_BIND_CONN:
1253                 session = iscsi_session_lookup(ev->u.b_conn.sid);
1254                 conn = iscsi_conn_lookup(ev->u.b_conn.sid, ev->u.b_conn.cid);
1255
1256                 if (session && conn)
1257                         ev->r.retcode = transport->bind_conn(session, conn,
1258                                         ev->u.b_conn.transport_eph,
1259                                         ev->u.b_conn.is_leading);
1260                 else
1261                         err = -EINVAL;
1262                 break;
1263         case ISCSI_UEVENT_SET_PARAM:
1264                 err = iscsi_set_param(transport, ev);
1265                 break;
1266         case ISCSI_UEVENT_START_CONN:
1267                 conn = iscsi_conn_lookup(ev->u.start_conn.sid, ev->u.start_conn.cid);
1268                 if (conn)
1269                         ev->r.retcode = transport->start_conn(conn);
1270                 else
1271                         err = -EINVAL;
1272                 break;
1273         case ISCSI_UEVENT_STOP_CONN:
1274                 conn = iscsi_conn_lookup(ev->u.stop_conn.sid, ev->u.stop_conn.cid);
1275                 if (conn)
1276                         transport->stop_conn(conn, ev->u.stop_conn.flag);
1277                 else
1278                         err = -EINVAL;
1279                 break;
1280         case ISCSI_UEVENT_SEND_PDU:
1281                 conn = iscsi_conn_lookup(ev->u.send_pdu.sid, ev->u.send_pdu.cid);
1282                 if (conn)
1283                         ev->r.retcode = transport->send_pdu(conn,
1284                                 (struct iscsi_hdr*)((char*)ev + sizeof(*ev)),
1285                                 (char*)ev + sizeof(*ev) + ev->u.send_pdu.hdr_size,
1286                                 ev->u.send_pdu.data_size);
1287                 else
1288                         err = -EINVAL;
1289                 break;
1290         case ISCSI_UEVENT_GET_STATS:
1291                 err = iscsi_if_get_stats(transport, nlh);
1292                 break;
1293         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1294         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1295         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1296                 err = iscsi_if_transport_ep(transport, ev, nlh->nlmsg_type);
1297                 break;
1298         case ISCSI_UEVENT_TGT_DSCVR:
1299                 err = iscsi_tgt_dscvr(transport, ev);
1300                 break;
1301         case ISCSI_UEVENT_SET_HOST_PARAM:
1302                 err = iscsi_set_host_param(transport, ev);
1303                 break;
1304         default:
1305                 err = -ENOSYS;
1306                 break;
1307         }
1308
1309         module_put(transport->owner);
1310         return err;
1311 }
1312
1313 /*
1314  * Get message from skb.  Each message is processed by iscsi_if_recv_msg.
1315  * Malformed skbs with wrong lengths or invalid creds are not processed.
1316  */
1317 static void
1318 iscsi_if_rx(struct sk_buff *skb)
1319 {
1320         mutex_lock(&rx_queue_mutex);
1321         while (skb->len >= NLMSG_SPACE(0)) {
1322                 int err;
1323                 uint32_t rlen;
1324                 struct nlmsghdr *nlh;
1325                 struct iscsi_uevent *ev;
1326
1327                 nlh = nlmsg_hdr(skb);
1328                 if (nlh->nlmsg_len < sizeof(*nlh) ||
1329                     skb->len < nlh->nlmsg_len) {
1330                         break;
1331                 }
1332
1333                 ev = NLMSG_DATA(nlh);
1334                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1335                 if (rlen > skb->len)
1336                         rlen = skb->len;
1337
1338                 err = iscsi_if_recv_msg(skb, nlh);
1339                 if (err) {
1340                         ev->type = ISCSI_KEVENT_IF_ERROR;
1341                         ev->iferror = err;
1342                 }
1343                 do {
1344                         /*
1345                          * special case for GET_STATS:
1346                          * on success - sending reply and stats from
1347                          * inside of if_recv_msg(),
1348                          * on error - fall through.
1349                          */
1350                         if (ev->type == ISCSI_UEVENT_GET_STATS && !err)
1351                                 break;
1352                         err = iscsi_if_send_reply(
1353                                 NETLINK_CREDS(skb)->pid, nlh->nlmsg_seq,
1354                                 nlh->nlmsg_type, 0, 0, ev, sizeof(*ev));
1355                 } while (err < 0 && err != -ECONNREFUSED);
1356                 skb_pull(skb, rlen);
1357         }
1358         mutex_unlock(&rx_queue_mutex);
1359 }
1360
1361 #define ISCSI_CLASS_ATTR(_prefix,_name,_mode,_show,_store)              \
1362 struct device_attribute dev_attr_##_prefix##_##_name =  \
1363         __ATTR(_name,_mode,_show,_store)
1364
1365 /*
1366  * iSCSI connection attrs
1367  */
1368 #define iscsi_conn_attr_show(param)                                     \
1369 static ssize_t                                                          \
1370 show_conn_param_##param(struct device *dev,                             \
1371                         struct device_attribute *attr, char *buf)       \
1372 {                                                                       \
1373         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev->parent);   \
1374         struct iscsi_transport *t = conn->transport;                    \
1375         return t->get_conn_param(conn, param, buf);                     \
1376 }
1377
1378 #define iscsi_conn_attr(field, param)                                   \
1379         iscsi_conn_attr_show(param)                                     \
1380 static ISCSI_CLASS_ATTR(conn, field, S_IRUGO, show_conn_param_##param,  \
1381                         NULL);
1382
1383 iscsi_conn_attr(max_recv_dlength, ISCSI_PARAM_MAX_RECV_DLENGTH);
1384 iscsi_conn_attr(max_xmit_dlength, ISCSI_PARAM_MAX_XMIT_DLENGTH);
1385 iscsi_conn_attr(header_digest, ISCSI_PARAM_HDRDGST_EN);
1386 iscsi_conn_attr(data_digest, ISCSI_PARAM_DATADGST_EN);
1387 iscsi_conn_attr(ifmarker, ISCSI_PARAM_IFMARKER_EN);
1388 iscsi_conn_attr(ofmarker, ISCSI_PARAM_OFMARKER_EN);
1389 iscsi_conn_attr(persistent_port, ISCSI_PARAM_PERSISTENT_PORT);
1390 iscsi_conn_attr(port, ISCSI_PARAM_CONN_PORT);
1391 iscsi_conn_attr(exp_statsn, ISCSI_PARAM_EXP_STATSN);
1392 iscsi_conn_attr(persistent_address, ISCSI_PARAM_PERSISTENT_ADDRESS);
1393 iscsi_conn_attr(address, ISCSI_PARAM_CONN_ADDRESS);
1394 iscsi_conn_attr(ping_tmo, ISCSI_PARAM_PING_TMO);
1395 iscsi_conn_attr(recv_tmo, ISCSI_PARAM_RECV_TMO);
1396
1397 /*
1398  * iSCSI session attrs
1399  */
1400 #define iscsi_session_attr_show(param, perm)                            \
1401 static ssize_t                                                          \
1402 show_session_param_##param(struct device *dev,                          \
1403                            struct device_attribute *attr, char *buf)    \
1404 {                                                                       \
1405         struct iscsi_cls_session *session =                             \
1406                 iscsi_dev_to_session(dev->parent);                      \
1407         struct iscsi_transport *t = session->transport;                 \
1408                                                                         \
1409         if (perm && !capable(CAP_SYS_ADMIN))                            \
1410                 return -EACCES;                                         \
1411         return t->get_session_param(session, param, buf);               \
1412 }
1413
1414 #define iscsi_session_attr(field, param, perm)                          \
1415         iscsi_session_attr_show(param, perm)                            \
1416 static ISCSI_CLASS_ATTR(sess, field, S_IRUGO, show_session_param_##param, \
1417                         NULL);
1418
1419 iscsi_session_attr(targetname, ISCSI_PARAM_TARGET_NAME, 0);
1420 iscsi_session_attr(initial_r2t, ISCSI_PARAM_INITIAL_R2T_EN, 0);
1421 iscsi_session_attr(max_outstanding_r2t, ISCSI_PARAM_MAX_R2T, 0);
1422 iscsi_session_attr(immediate_data, ISCSI_PARAM_IMM_DATA_EN, 0);
1423 iscsi_session_attr(first_burst_len, ISCSI_PARAM_FIRST_BURST, 0);
1424 iscsi_session_attr(max_burst_len, ISCSI_PARAM_MAX_BURST, 0);
1425 iscsi_session_attr(data_pdu_in_order, ISCSI_PARAM_PDU_INORDER_EN, 0);
1426 iscsi_session_attr(data_seq_in_order, ISCSI_PARAM_DATASEQ_INORDER_EN, 0);
1427 iscsi_session_attr(erl, ISCSI_PARAM_ERL, 0);
1428 iscsi_session_attr(tpgt, ISCSI_PARAM_TPGT, 0);
1429 iscsi_session_attr(username, ISCSI_PARAM_USERNAME, 1);
1430 iscsi_session_attr(username_in, ISCSI_PARAM_USERNAME_IN, 1);
1431 iscsi_session_attr(password, ISCSI_PARAM_PASSWORD, 1);
1432 iscsi_session_attr(password_in, ISCSI_PARAM_PASSWORD_IN, 1);
1433 iscsi_session_attr(fast_abort, ISCSI_PARAM_FAST_ABORT, 0);
1434 iscsi_session_attr(abort_tmo, ISCSI_PARAM_ABORT_TMO, 0);
1435 iscsi_session_attr(lu_reset_tmo, ISCSI_PARAM_LU_RESET_TMO, 0);
1436
1437 static ssize_t
1438 show_priv_session_state(struct device *dev, struct device_attribute *attr,
1439                         char *buf)
1440 {
1441         struct iscsi_cls_session *session = iscsi_dev_to_session(dev->parent);
1442         return sprintf(buf, "%s\n", iscsi_session_state_name(session->state));
1443 }
1444 static ISCSI_CLASS_ATTR(priv_sess, state, S_IRUGO, show_priv_session_state,
1445                         NULL);
1446
1447 #define iscsi_priv_session_attr_show(field, format)                     \
1448 static ssize_t                                                          \
1449 show_priv_session_##field(struct device *dev,                           \
1450                           struct device_attribute *attr, char *buf)     \
1451 {                                                                       \
1452         struct iscsi_cls_session *session =                             \
1453                         iscsi_dev_to_session(dev->parent);              \
1454         return sprintf(buf, format"\n", session->field);                \
1455 }
1456
1457 #define iscsi_priv_session_attr(field, format)                          \
1458         iscsi_priv_session_attr_show(field, format)                     \
1459 static ISCSI_CLASS_ATTR(priv_sess, field, S_IRUGO, show_priv_session_##field, \
1460                         NULL)
1461 iscsi_priv_session_attr(recovery_tmo, "%d");
1462
1463 /*
1464  * iSCSI host attrs
1465  */
1466 #define iscsi_host_attr_show(param)                                     \
1467 static ssize_t                                                          \
1468 show_host_param_##param(struct device *dev,                             \
1469                         struct device_attribute *attr, char *buf)       \
1470 {                                                                       \
1471         struct Scsi_Host *shost = transport_class_to_shost(dev);        \
1472         struct iscsi_internal *priv = to_iscsi_internal(shost->transportt); \
1473         return priv->iscsi_transport->get_host_param(shost, param, buf); \
1474 }
1475
1476 #define iscsi_host_attr(field, param)                                   \
1477         iscsi_host_attr_show(param)                                     \
1478 static ISCSI_CLASS_ATTR(host, field, S_IRUGO, show_host_param_##param,  \
1479                         NULL);
1480
1481 iscsi_host_attr(netdev, ISCSI_HOST_PARAM_NETDEV_NAME);
1482 iscsi_host_attr(hwaddress, ISCSI_HOST_PARAM_HWADDRESS);
1483 iscsi_host_attr(ipaddress, ISCSI_HOST_PARAM_IPADDRESS);
1484 iscsi_host_attr(initiatorname, ISCSI_HOST_PARAM_INITIATOR_NAME);
1485
1486 #define SETUP_PRIV_SESSION_RD_ATTR(field)                               \
1487 do {                                                                    \
1488         priv->session_attrs[count] = &dev_attr_priv_sess_##field; \
1489         count++;                                                        \
1490 } while (0)
1491
1492
1493 #define SETUP_SESSION_RD_ATTR(field, param_flag)                        \
1494 do {                                                                    \
1495         if (tt->param_mask & param_flag) {                              \
1496                 priv->session_attrs[count] = &dev_attr_sess_##field; \
1497                 count++;                                                \
1498         }                                                               \
1499 } while (0)
1500
1501 #define SETUP_CONN_RD_ATTR(field, param_flag)                           \
1502 do {                                                                    \
1503         if (tt->param_mask & param_flag) {                              \
1504                 priv->conn_attrs[count] = &dev_attr_conn_##field; \
1505                 count++;                                                \
1506         }                                                               \
1507 } while (0)
1508
1509 #define SETUP_HOST_RD_ATTR(field, param_flag)                           \
1510 do {                                                                    \
1511         if (tt->host_param_mask & param_flag) {                         \
1512                 priv->host_attrs[count] = &dev_attr_host_##field; \
1513                 count++;                                                \
1514         }                                                               \
1515 } while (0)
1516
1517 static int iscsi_session_match(struct attribute_container *cont,
1518                            struct device *dev)
1519 {
1520         struct iscsi_cls_session *session;
1521         struct Scsi_Host *shost;
1522         struct iscsi_internal *priv;
1523
1524         if (!iscsi_is_session_dev(dev))
1525                 return 0;
1526
1527         session = iscsi_dev_to_session(dev);
1528         shost = iscsi_session_to_shost(session);
1529         if (!shost->transportt)
1530                 return 0;
1531
1532         priv = to_iscsi_internal(shost->transportt);
1533         if (priv->session_cont.ac.class != &iscsi_session_class.class)
1534                 return 0;
1535
1536         return &priv->session_cont.ac == cont;
1537 }
1538
1539 static int iscsi_conn_match(struct attribute_container *cont,
1540                            struct device *dev)
1541 {
1542         struct iscsi_cls_session *session;
1543         struct iscsi_cls_conn *conn;
1544         struct Scsi_Host *shost;
1545         struct iscsi_internal *priv;
1546
1547         if (!iscsi_is_conn_dev(dev))
1548                 return 0;
1549
1550         conn = iscsi_dev_to_conn(dev);
1551         session = iscsi_dev_to_session(conn->dev.parent);
1552         shost = iscsi_session_to_shost(session);
1553
1554         if (!shost->transportt)
1555                 return 0;
1556
1557         priv = to_iscsi_internal(shost->transportt);
1558         if (priv->conn_cont.ac.class != &iscsi_connection_class.class)
1559                 return 0;
1560
1561         return &priv->conn_cont.ac == cont;
1562 }
1563
1564 static int iscsi_host_match(struct attribute_container *cont,
1565                             struct device *dev)
1566 {
1567         struct Scsi_Host *shost;
1568         struct iscsi_internal *priv;
1569
1570         if (!scsi_is_host_device(dev))
1571                 return 0;
1572
1573         shost = dev_to_shost(dev);
1574         if (!shost->transportt  ||
1575             shost->transportt->host_attrs.ac.class != &iscsi_host_class.class)
1576                 return 0;
1577
1578         priv = to_iscsi_internal(shost->transportt);
1579         return &priv->t.host_attrs.ac == cont;
1580 }
1581
1582 struct scsi_transport_template *
1583 iscsi_register_transport(struct iscsi_transport *tt)
1584 {
1585         struct iscsi_internal *priv;
1586         unsigned long flags;
1587         int count = 0, err;
1588
1589         BUG_ON(!tt);
1590
1591         priv = iscsi_if_transport_lookup(tt);
1592         if (priv)
1593                 return NULL;
1594
1595         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1596         if (!priv)
1597                 return NULL;
1598         INIT_LIST_HEAD(&priv->list);
1599         priv->daemon_pid = -1;
1600         priv->iscsi_transport = tt;
1601         priv->t.user_scan = iscsi_user_scan;
1602
1603         priv->dev.class = &iscsi_transport_class;
1604         snprintf(priv->dev.bus_id, BUS_ID_SIZE, "%s", tt->name);
1605         err = device_register(&priv->dev);
1606         if (err)
1607                 goto free_priv;
1608
1609         err = sysfs_create_group(&priv->dev.kobj, &iscsi_transport_group);
1610         if (err)
1611                 goto unregister_dev;
1612
1613         /* host parameters */
1614         priv->t.host_attrs.ac.attrs = &priv->host_attrs[0];
1615         priv->t.host_attrs.ac.class = &iscsi_host_class.class;
1616         priv->t.host_attrs.ac.match = iscsi_host_match;
1617         priv->t.host_size = sizeof(struct iscsi_cls_host);
1618         transport_container_register(&priv->t.host_attrs);
1619
1620         SETUP_HOST_RD_ATTR(netdev, ISCSI_HOST_NETDEV_NAME);
1621         SETUP_HOST_RD_ATTR(ipaddress, ISCSI_HOST_IPADDRESS);
1622         SETUP_HOST_RD_ATTR(hwaddress, ISCSI_HOST_HWADDRESS);
1623         SETUP_HOST_RD_ATTR(initiatorname, ISCSI_HOST_INITIATOR_NAME);
1624         BUG_ON(count > ISCSI_HOST_ATTRS);
1625         priv->host_attrs[count] = NULL;
1626         count = 0;
1627
1628         /* connection parameters */
1629         priv->conn_cont.ac.attrs = &priv->conn_attrs[0];
1630         priv->conn_cont.ac.class = &iscsi_connection_class.class;
1631         priv->conn_cont.ac.match = iscsi_conn_match;
1632         transport_container_register(&priv->conn_cont);
1633
1634         SETUP_CONN_RD_ATTR(max_recv_dlength, ISCSI_MAX_RECV_DLENGTH);
1635         SETUP_CONN_RD_ATTR(max_xmit_dlength, ISCSI_MAX_XMIT_DLENGTH);
1636         SETUP_CONN_RD_ATTR(header_digest, ISCSI_HDRDGST_EN);
1637         SETUP_CONN_RD_ATTR(data_digest, ISCSI_DATADGST_EN);
1638         SETUP_CONN_RD_ATTR(ifmarker, ISCSI_IFMARKER_EN);
1639         SETUP_CONN_RD_ATTR(ofmarker, ISCSI_OFMARKER_EN);
1640         SETUP_CONN_RD_ATTR(address, ISCSI_CONN_ADDRESS);
1641         SETUP_CONN_RD_ATTR(port, ISCSI_CONN_PORT);
1642         SETUP_CONN_RD_ATTR(exp_statsn, ISCSI_EXP_STATSN);
1643         SETUP_CONN_RD_ATTR(persistent_address, ISCSI_PERSISTENT_ADDRESS);
1644         SETUP_CONN_RD_ATTR(persistent_port, ISCSI_PERSISTENT_PORT);
1645         SETUP_CONN_RD_ATTR(ping_tmo, ISCSI_PING_TMO);
1646         SETUP_CONN_RD_ATTR(recv_tmo, ISCSI_RECV_TMO);
1647
1648         BUG_ON(count > ISCSI_CONN_ATTRS);
1649         priv->conn_attrs[count] = NULL;
1650         count = 0;
1651
1652         /* session parameters */
1653         priv->session_cont.ac.attrs = &priv->session_attrs[0];
1654         priv->session_cont.ac.class = &iscsi_session_class.class;
1655         priv->session_cont.ac.match = iscsi_session_match;
1656         transport_container_register(&priv->session_cont);
1657
1658         SETUP_SESSION_RD_ATTR(initial_r2t, ISCSI_INITIAL_R2T_EN);
1659         SETUP_SESSION_RD_ATTR(max_outstanding_r2t, ISCSI_MAX_R2T);
1660         SETUP_SESSION_RD_ATTR(immediate_data, ISCSI_IMM_DATA_EN);
1661         SETUP_SESSION_RD_ATTR(first_burst_len, ISCSI_FIRST_BURST);
1662         SETUP_SESSION_RD_ATTR(max_burst_len, ISCSI_MAX_BURST);
1663         SETUP_SESSION_RD_ATTR(data_pdu_in_order, ISCSI_PDU_INORDER_EN);
1664         SETUP_SESSION_RD_ATTR(data_seq_in_order, ISCSI_DATASEQ_INORDER_EN);
1665         SETUP_SESSION_RD_ATTR(erl, ISCSI_ERL);
1666         SETUP_SESSION_RD_ATTR(targetname, ISCSI_TARGET_NAME);
1667         SETUP_SESSION_RD_ATTR(tpgt, ISCSI_TPGT);
1668         SETUP_SESSION_RD_ATTR(password, ISCSI_USERNAME);
1669         SETUP_SESSION_RD_ATTR(password_in, ISCSI_USERNAME_IN);
1670         SETUP_SESSION_RD_ATTR(username, ISCSI_PASSWORD);
1671         SETUP_SESSION_RD_ATTR(username_in, ISCSI_PASSWORD_IN);
1672         SETUP_SESSION_RD_ATTR(fast_abort, ISCSI_FAST_ABORT);
1673         SETUP_SESSION_RD_ATTR(abort_tmo, ISCSI_ABORT_TMO);
1674         SETUP_SESSION_RD_ATTR(lu_reset_tmo,ISCSI_LU_RESET_TMO);
1675         SETUP_PRIV_SESSION_RD_ATTR(recovery_tmo);
1676         SETUP_PRIV_SESSION_RD_ATTR(state);
1677
1678         BUG_ON(count > ISCSI_SESSION_ATTRS);
1679         priv->session_attrs[count] = NULL;
1680
1681         spin_lock_irqsave(&iscsi_transport_lock, flags);
1682         list_add(&priv->list, &iscsi_transports);
1683         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1684
1685         printk(KERN_NOTICE "iscsi: registered transport (%s)\n", tt->name);
1686         return &priv->t;
1687
1688 unregister_dev:
1689         device_unregister(&priv->dev);
1690 free_priv:
1691         kfree(priv);
1692         return NULL;
1693 }
1694 EXPORT_SYMBOL_GPL(iscsi_register_transport);
1695
1696 int iscsi_unregister_transport(struct iscsi_transport *tt)
1697 {
1698         struct iscsi_internal *priv;
1699         unsigned long flags;
1700
1701         BUG_ON(!tt);
1702
1703         mutex_lock(&rx_queue_mutex);
1704
1705         priv = iscsi_if_transport_lookup(tt);
1706         BUG_ON (!priv);
1707
1708         spin_lock_irqsave(&iscsi_transport_lock, flags);
1709         list_del(&priv->list);
1710         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1711
1712         transport_container_unregister(&priv->conn_cont);
1713         transport_container_unregister(&priv->session_cont);
1714         transport_container_unregister(&priv->t.host_attrs);
1715
1716         sysfs_remove_group(&priv->dev.kobj, &iscsi_transport_group);
1717         device_unregister(&priv->dev);
1718         mutex_unlock(&rx_queue_mutex);
1719
1720         return 0;
1721 }
1722 EXPORT_SYMBOL_GPL(iscsi_unregister_transport);
1723
1724 static __init int iscsi_transport_init(void)
1725 {
1726         int err;
1727
1728         printk(KERN_INFO "Loading iSCSI transport class v%s.\n",
1729                 ISCSI_TRANSPORT_VERSION);
1730
1731         atomic_set(&iscsi_session_nr, 0);
1732
1733         err = class_register(&iscsi_transport_class);
1734         if (err)
1735                 return err;
1736
1737         err = transport_class_register(&iscsi_host_class);
1738         if (err)
1739                 goto unregister_transport_class;
1740
1741         err = transport_class_register(&iscsi_connection_class);
1742         if (err)
1743                 goto unregister_host_class;
1744
1745         err = transport_class_register(&iscsi_session_class);
1746         if (err)
1747                 goto unregister_conn_class;
1748
1749         nls = netlink_kernel_create(&init_net, NETLINK_ISCSI, 1, iscsi_if_rx, NULL,
1750                         THIS_MODULE);
1751         if (!nls) {
1752                 err = -ENOBUFS;
1753                 goto unregister_session_class;
1754         }
1755
1756         iscsi_eh_timer_workq = create_singlethread_workqueue("iscsi_eh");
1757         if (!iscsi_eh_timer_workq)
1758                 goto release_nls;
1759
1760         return 0;
1761
1762 release_nls:
1763         netlink_kernel_release(nls);
1764 unregister_session_class:
1765         transport_class_unregister(&iscsi_session_class);
1766 unregister_conn_class:
1767         transport_class_unregister(&iscsi_connection_class);
1768 unregister_host_class:
1769         transport_class_unregister(&iscsi_host_class);
1770 unregister_transport_class:
1771         class_unregister(&iscsi_transport_class);
1772         return err;
1773 }
1774
1775 static void __exit iscsi_transport_exit(void)
1776 {
1777         destroy_workqueue(iscsi_eh_timer_workq);
1778         netlink_kernel_release(nls);
1779         transport_class_unregister(&iscsi_connection_class);
1780         transport_class_unregister(&iscsi_session_class);
1781         transport_class_unregister(&iscsi_host_class);
1782         class_unregister(&iscsi_transport_class);
1783 }
1784
1785 module_init(iscsi_transport_init);
1786 module_exit(iscsi_transport_exit);
1787
1788 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
1789               "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
1790               "Alex Aizman <itn780@yahoo.com>");
1791 MODULE_DESCRIPTION("iSCSI Transport Interface");
1792 MODULE_LICENSE("GPL");
1793 MODULE_VERSION(ISCSI_TRANSPORT_VERSION);