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 static int iscsi_iter_session_fn(struct device *dev, void *data)
 283 {
 284         void (* fn) (struct iscsi_cls_session *) = data;
 285
 286         if (!iscsi_is_session_dev(dev))
 287                 return 0;
 288         fn(iscsi_dev_to_session(dev));
 289         return 0;
 290 }
 291
 292 void iscsi_host_for_each_session(struct Scsi_Host *shost,
 293                                  void (*fn)(struct iscsi_cls_session *))
 294 {
 295         device_for_each_child(&shost->shost_gendev, fn,
 296                               iscsi_iter_session_fn);
 297 }
 298 EXPORT_SYMBOL_GPL(iscsi_host_for_each_session);
 299
 300 /**
 301  * iscsi_scan_finished - helper to report when running scans are done
 302  * @shost: scsi host
 303  * @time: scan run time
 304  *
 305  * This function can be used by drives like qla4xxx to report to the scsi
 306  * layer when the scans it kicked off at module load time are done.
 307  */
 308 int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time)
 309 {
 310         struct iscsi_cls_host *ihost = shost->shost_data;
 311         /*
 312          * qla4xxx will have kicked off some session unblocks before calling
 313          * scsi_scan_host, so just wait for them to complete.
 314          */
 315         return !atomic_read(&ihost->nr_scans);
 316 }
 317 EXPORT_SYMBOL_GPL(iscsi_scan_finished);
 318
 319 static int iscsi_user_scan(struct Scsi_Host *shost, uint channel,
 320                            uint id, uint lun)
 321 {
 322         struct iscsi_cls_host *ihost = shost->shost_data;
 323         struct iscsi_cls_session *session;
 324
 325         mutex_lock(&ihost->mutex);
 326         list_for_each_entry(session, &ihost->sessions, host_list) {
 327                 if ((channel == SCAN_WILD_CARD || channel == 0) &&
 328                     (id == SCAN_WILD_CARD || id == session->target_id))
 329                         scsi_scan_target(&session->dev, 0,
 330                                          session->target_id, lun, 1);
 331         }
 332         mutex_unlock(&ihost->mutex);
 333
 334         return 0;
 335 }
 336
 337 static void iscsi_scan_session(struct work_struct *work)
 338 {
 339         struct iscsi_cls_session *session =
 340                         container_of(work, struct iscsi_cls_session, scan_work);
 341         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 342         struct iscsi_cls_host *ihost = shost->shost_data;
 343         unsigned long flags;
 344
 345         spin_lock_irqsave(&session->lock, flags);
 346         if (session->state != ISCSI_SESSION_LOGGED_IN) {
 347                 spin_unlock_irqrestore(&session->lock, flags);
 348                 goto done;
 349         }
 350         spin_unlock_irqrestore(&session->lock, flags);
 351
 352         scsi_scan_target(&session->dev, 0, session->target_id,
 353                          SCAN_WILD_CARD, 1);
 354 done:
 355         atomic_dec(&ihost->nr_scans);
 356 }
 357
 358 static void session_recovery_timedout(struct work_struct *work)
 359 {
 360         struct iscsi_cls_session *session =
 361                 container_of(work, struct iscsi_cls_session,
 362                              recovery_work.work);
 363         unsigned long flags;
 364
 365         iscsi_cls_session_printk(KERN_INFO, session,
 366                                  "session recovery timed out after %d secs\n",
 367                                  session->recovery_tmo);
 368
 369         spin_lock_irqsave(&session->lock, flags);
 370         switch (session->state) {
 371         case ISCSI_SESSION_FAILED:
 372                 session->state = ISCSI_SESSION_FREE;
 373                 break;
 374         case ISCSI_SESSION_LOGGED_IN:
 375         case ISCSI_SESSION_FREE:
 376                 /* we raced with the unblock's flush */
 377                 spin_unlock_irqrestore(&session->lock, flags);
 378                 return;
 379         }
 380         spin_unlock_irqrestore(&session->lock, flags);
 381
 382         if (session->transport->session_recovery_timedout)
 383                 session->transport->session_recovery_timedout(session);
 384
 385         scsi_target_unblock(&session->dev);
 386 }
 387
 388 static void __iscsi_unblock_session(struct work_struct *work)
 389 {
 390         struct iscsi_cls_session *session =
 391                         container_of(work, struct iscsi_cls_session,
 392                                      unblock_work);
 393         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 394         struct iscsi_cls_host *ihost = shost->shost_data;
 395         unsigned long flags;
 396
 397         /*
 398          * The recovery and unblock work get run from the same workqueue,
 399          * so try to cancel it if it was going to run after this unblock.
 400          */
 401         cancel_delayed_work(&session->recovery_work);
 402         spin_lock_irqsave(&session->lock, flags);
 403         session->state = ISCSI_SESSION_LOGGED_IN;
 404         spin_unlock_irqrestore(&session->lock, flags);
 405         /* start IO */
 406         scsi_target_unblock(&session->dev);
 407         /*
 408          * Only do kernel scanning if the driver is properly hooked into
 409          * the async scanning code (drivers like iscsi_tcp do login and
 410          * scanning from userspace).
 411          */
 412         if (shost->hostt->scan_finished) {
 413                 if (queue_work(ihost->scan_workq, &session->scan_work))
 414                         atomic_inc(&ihost->nr_scans);
 415         }
 416 }
 417
 418 /**
 419  * iscsi_unblock_session - set a session as logged in and start IO.
 420  * @session: iscsi session
 421  *
 422  * Mark a session as ready to accept IO.
 423  */
 424 void iscsi_unblock_session(struct iscsi_cls_session *session)
 425 {
 426         queue_work(iscsi_eh_timer_workq, &session->unblock_work);
 427         /*
 428          * make sure all the events have completed before tell the driver
 429          * it is safe
 430          */
 431         flush_workqueue(iscsi_eh_timer_workq);
 432 }
 433 EXPORT_SYMBOL_GPL(iscsi_unblock_session);
 434
 435 static void __iscsi_block_session(struct work_struct *work)
 436 {
 437         struct iscsi_cls_session *session =
 438                         container_of(work, struct iscsi_cls_session,
 439                                      block_work);
 440         unsigned long flags;
 441
 442         spin_lock_irqsave(&session->lock, flags);
 443         session->state = ISCSI_SESSION_FAILED;
 444         spin_unlock_irqrestore(&session->lock, flags);
 445         scsi_target_block(&session->dev);
 446         queue_delayed_work(iscsi_eh_timer_workq, &session->recovery_work,
 447                            session->recovery_tmo * HZ);
 448 }
 449
 450 void iscsi_block_session(struct iscsi_cls_session *session)
 451 {
 452         queue_work(iscsi_eh_timer_workq, &session->block_work);
 453 }
 454 EXPORT_SYMBOL_GPL(iscsi_block_session);
 455
 456 static void __iscsi_unbind_session(struct work_struct *work)
 457 {
 458         struct iscsi_cls_session *session =
 459                         container_of(work, struct iscsi_cls_session,
 460                                      unbind_work);
 461         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 462         struct iscsi_cls_host *ihost = shost->shost_data;
 463
 464         /* Prevent new scans and make sure scanning is not in progress */
 465         mutex_lock(&ihost->mutex);
 466         if (list_empty(&session->host_list)) {
 467                 mutex_unlock(&ihost->mutex);
 468                 return;
 469         }
 470         list_del_init(&session->host_list);
 471         mutex_unlock(&ihost->mutex);
 472
 473         scsi_remove_target(&session->dev);
 474         iscsi_session_event(session, ISCSI_KEVENT_UNBIND_SESSION);
 475 }
 476
 477 static int iscsi_unbind_session(struct iscsi_cls_session *session)
 478 {
 479         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 480         struct iscsi_cls_host *ihost = shost->shost_data;
 481
 482         return queue_work(ihost->scan_workq, &session->unbind_work);
 483 }
 484
 485 struct iscsi_cls_session *
 486 iscsi_alloc_session(struct Scsi_Host *shost,
 487                     struct iscsi_transport *transport)
 488 {
 489         struct iscsi_cls_session *session;
 490
 491         session = kzalloc(sizeof(*session) + transport->sessiondata_size,
 492                           GFP_KERNEL);
 493         if (!session)
 494                 return NULL;
 495
 496         session->transport = transport;
 497         session->recovery_tmo = 120;
 498         session->state = ISCSI_SESSION_FREE;
 499         INIT_DELAYED_WORK(&session->recovery_work, session_recovery_timedout);
 500         INIT_LIST_HEAD(&session->host_list);
 501         INIT_LIST_HEAD(&session->sess_list);
 502         INIT_WORK(&session->unblock_work, __iscsi_unblock_session);
 503         INIT_WORK(&session->block_work, __iscsi_block_session);
 504         INIT_WORK(&session->unbind_work, __iscsi_unbind_session);
 505         INIT_WORK(&session->scan_work, iscsi_scan_session);
 506         spin_lock_init(&session->lock);
 507
 508         /* this is released in the dev's release function */
 509         scsi_host_get(shost);
 510         session->dev.parent = &shost->shost_gendev;
 511         session->dev.release = iscsi_session_release;
 512         device_initialize(&session->dev);
 513         if (transport->sessiondata_size)
 514                 session->dd_data = &session[1];
 515         return session;
 516 }
 517 EXPORT_SYMBOL_GPL(iscsi_alloc_session);
 518
 519 int iscsi_add_session(struct iscsi_cls_session *session, unsigned int target_id)
 520 {
 521         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 522         struct iscsi_cls_host *ihost;
 523         unsigned long flags;
 524         int err;
 525
 526         ihost = shost->shost_data;
 527         session->sid = atomic_add_return(1, &iscsi_session_nr);
 528         session->target_id = target_id;
 529
 530         snprintf(session->dev.bus_id, BUS_ID_SIZE, "session%u",
 531                  session->sid);
 532         err = device_add(&session->dev);
 533         if (err) {
 534                 iscsi_cls_session_printk(KERN_ERR, session,
 535                                          "could not register session's dev\n");
 536                 goto release_host;
 537         }
 538         transport_register_device(&session->dev);
 539
 540         spin_lock_irqsave(&sesslock, flags);
 541         list_add(&session->sess_list, &sesslist);
 542         spin_unlock_irqrestore(&sesslock, flags);
 543
 544         mutex_lock(&ihost->mutex);
 545         list_add(&session->host_list, &ihost->sessions);
 546         mutex_unlock(&ihost->mutex);
 547
 548         iscsi_session_event(session, ISCSI_KEVENT_CREATE_SESSION);
 549         return 0;
 550
 551 release_host:
 552         scsi_host_put(shost);
 553         return err;
 554 }
 555 EXPORT_SYMBOL_GPL(iscsi_add_session);
 556
 557 /**
 558  * iscsi_create_session - create iscsi class session
 559  * @shost: scsi host
 560  * @transport: iscsi transport
 561  * @target_id: which target
 562  *
 563  * This can be called from a LLD or iscsi_transport.
 564  */
 565 struct iscsi_cls_session *
 566 iscsi_create_session(struct Scsi_Host *shost,
 567                      struct iscsi_transport *transport,
 568                      unsigned int target_id)
 569 {
 570         struct iscsi_cls_session *session;
 571
 572         session = iscsi_alloc_session(shost, transport);
 573         if (!session)
 574                 return NULL;
 575
 576         if (iscsi_add_session(session, target_id)) {
 577                 iscsi_free_session(session);
 578                 return NULL;
 579         }
 580         return session;
 581 }
 582 EXPORT_SYMBOL_GPL(iscsi_create_session);
 583
 584 static void iscsi_conn_release(struct device *dev)
 585 {
 586         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev);
 587         struct device *parent = conn->dev.parent;
 588
 589         kfree(conn);
 590         put_device(parent);
 591 }
 592
 593 static int iscsi_is_conn_dev(const struct device *dev)
 594 {
 595         return dev->release == iscsi_conn_release;
 596 }
 597
 598 static int iscsi_iter_destroy_conn_fn(struct device *dev, void *data)
 599 {
 600         if (!iscsi_is_conn_dev(dev))
 601                 return 0;
 602         return iscsi_destroy_conn(iscsi_dev_to_conn(dev));
 603 }
 604
 605 void iscsi_remove_session(struct iscsi_cls_session *session)
 606 {
 607         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 608         struct iscsi_cls_host *ihost = shost->shost_data;
 609         unsigned long flags;
 610         int err;
 611
 612         spin_lock_irqsave(&sesslock, flags);
 613         list_del(&session->sess_list);
 614         spin_unlock_irqrestore(&sesslock, flags);
 615
 616         /* make sure there are no blocks/unblocks queued */
 617         flush_workqueue(iscsi_eh_timer_workq);
 618         /* make sure the timedout callout is not running */
 619         if (!cancel_delayed_work(&session->recovery_work))
 620                 flush_workqueue(iscsi_eh_timer_workq);
 621         /*
 622          * If we are blocked let commands flow again. The lld or iscsi
 623          * layer should set up the queuecommand to fail commands.
 624          * We assume that LLD will not be calling block/unblock while
 625          * removing the session.
 626          */
 627         spin_lock_irqsave(&session->lock, flags);
 628         session->state = ISCSI_SESSION_FREE;
 629         spin_unlock_irqrestore(&session->lock, flags);
 630
 631         scsi_target_unblock(&session->dev);
 632         /* flush running scans then delete devices */
 633         flush_workqueue(ihost->scan_workq);
 634         __iscsi_unbind_session(&session->unbind_work);
 635
 636         /* hw iscsi may not have removed all connections from session */
 637         err = device_for_each_child(&session->dev, NULL,
 638                                     iscsi_iter_destroy_conn_fn);
 639         if (err)
 640                 iscsi_cls_session_printk(KERN_ERR, session,
 641                                          "Could not delete all connections "
 642                                          "for session. Error %d.\n", err);
 643
 644         transport_unregister_device(&session->dev);
 645         device_del(&session->dev);
 646 }
 647 EXPORT_SYMBOL_GPL(iscsi_remove_session);
 648
 649 void iscsi_free_session(struct iscsi_cls_session *session)
 650 {
 651         iscsi_session_event(session, ISCSI_KEVENT_DESTROY_SESSION);
 652         put_device(&session->dev);
 653 }
 654 EXPORT_SYMBOL_GPL(iscsi_free_session);
 655
 656 /**
 657  * iscsi_destroy_session - destroy iscsi session
 658  * @session: iscsi_session
 659  *
 660  * Can be called by a LLD or iscsi_transport. There must not be
 661  * any running connections.
 662  */
 663 int iscsi_destroy_session(struct iscsi_cls_session *session)
 664 {
 665         iscsi_remove_session(session);
 666         iscsi_free_session(session);
 667         return 0;
 668 }
 669 EXPORT_SYMBOL_GPL(iscsi_destroy_session);
 670
 671 /**
 672  * iscsi_create_conn - create iscsi class connection
 673  * @session: iscsi cls session
 674  * @cid: connection id
 675  *
 676  * This can be called from a LLD or iscsi_transport. The connection
 677  * is child of the session so cid must be unique for all connections
 678  * on the session.
 679  *
 680  * Since we do not support MCS, cid will normally be zero. In some cases
 681  * for software iscsi we could be trying to preallocate a connection struct
 682  * in which case there could be two connection structs and cid would be
 683  * non-zero.
 684  */
 685 struct iscsi_cls_conn *
 686 iscsi_create_conn(struct iscsi_cls_session *session, uint32_t cid)
 687 {
 688         struct iscsi_transport *transport = session->transport;
 689         struct iscsi_cls_conn *conn;
 690         unsigned long flags;
 691         int err;
 692
 693         conn = kzalloc(sizeof(*conn) + transport->conndata_size, GFP_KERNEL);
 694         if (!conn)
 695                 return NULL;
 696
 697         if (transport->conndata_size)
 698                 conn->dd_data = &conn[1];
 699
 700         INIT_LIST_HEAD(&conn->conn_list);
 701         conn->transport = transport;
 702         conn->cid = cid;
 703
 704         /* this is released in the dev's release function */
 705         if (!get_device(&session->dev))
 706                 goto free_conn;
 707
 708         snprintf(conn->dev.bus_id, BUS_ID_SIZE, "connection%d:%u",
 709                  session->sid, cid);
 710         conn->dev.parent = &session->dev;
 711         conn->dev.release = iscsi_conn_release;
 712         err = device_register(&conn->dev);
 713         if (err) {
 714                 iscsi_cls_session_printk(KERN_ERR, session, "could not "
 715                                          "register connection's dev\n");
 716                 goto release_parent_ref;
 717         }
 718         transport_register_device(&conn->dev);
 719
 720         spin_lock_irqsave(&connlock, flags);
 721         list_add(&conn->conn_list, &connlist);
 722         conn->active = 1;
 723         spin_unlock_irqrestore(&connlock, flags);
 724         return conn;
 725
 726 release_parent_ref:
 727         put_device(&session->dev);
 728 free_conn:
 729         kfree(conn);
 730         return NULL;
 731 }
 732
 733 EXPORT_SYMBOL_GPL(iscsi_create_conn);
 734
 735 /**
 736  * iscsi_destroy_conn - destroy iscsi class connection
 737  * @conn: iscsi cls session
 738  *
 739  * This can be called from a LLD or iscsi_transport.
 740  */
 741 int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
 742 {
 743         unsigned long flags;
 744
 745         spin_lock_irqsave(&connlock, flags);
 746         conn->active = 0;
 747         list_del(&conn->conn_list);
 748         spin_unlock_irqrestore(&connlock, flags);
 749
 750         transport_unregister_device(&conn->dev);
 751         device_unregister(&conn->dev);
 752         return 0;
 753 }
 754 EXPORT_SYMBOL_GPL(iscsi_destroy_conn);
 755
 756 /*
 757  * iscsi interface functions
 758  */
 759 static struct iscsi_internal *
 760 iscsi_if_transport_lookup(struct iscsi_transport *tt)
 761 {
 762         struct iscsi_internal *priv;
 763         unsigned long flags;
 764
 765         spin_lock_irqsave(&iscsi_transport_lock, flags);
 766         list_for_each_entry(priv, &iscsi_transports, list) {
 767                 if (tt == priv->iscsi_transport) {
 768                         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 769                         return priv;
 770                 }
 771         }
 772         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 773         return NULL;
 774 }
 775
 776 static int
 777 iscsi_broadcast_skb(struct sk_buff *skb, gfp_t gfp)
 778 {
 779         int rc;
 780
 781         rc = netlink_broadcast(nls, skb, 0, 1, gfp);
 782         if (rc < 0) {
 783                 printk(KERN_ERR "iscsi: can not broadcast skb (%d)\n", rc);
 784                 return rc;
 785         }
 786
 787         return 0;
 788 }
 789
 790 static int
 791 iscsi_unicast_skb(struct sk_buff *skb, int pid)
 792 {
 793         int rc;
 794
 795         rc = netlink_unicast(nls, skb, pid, MSG_DONTWAIT);
 796         if (rc < 0) {
 797                 printk(KERN_ERR "iscsi: can not unicast skb (%d)\n", rc);
 798                 return rc;
 799         }
 800
 801         return 0;
 802 }
 803
 804 int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
 805                    char *data, uint32_t data_size)
 806 {
 807         struct nlmsghdr *nlh;
 808         struct sk_buff *skb;
 809         struct iscsi_uevent *ev;
 810         char *pdu;
 811         struct iscsi_internal *priv;
 812         int len = NLMSG_SPACE(sizeof(*ev) + sizeof(struct iscsi_hdr) +
 813                               data_size);
 814
 815         priv = iscsi_if_transport_lookup(conn->transport);
 816         if (!priv)
 817                 return -EINVAL;
 818
 819         skb = alloc_skb(len, GFP_ATOMIC);
 820         if (!skb) {
 821                 iscsi_conn_error(conn, ISCSI_ERR_CONN_FAILED);
 822                 iscsi_cls_conn_printk(KERN_ERR, conn, "can not deliver "
 823                                       "control PDU: OOM\n");
 824                 return -ENOMEM;
 825         }
 826
 827         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
 828         ev = NLMSG_DATA(nlh);
 829         memset(ev, 0, sizeof(*ev));
 830         ev->transport_handle = iscsi_handle(conn->transport);
 831         ev->type = ISCSI_KEVENT_RECV_PDU;
 832         ev->r.recv_req.cid = conn->cid;
 833         ev->r.recv_req.sid = iscsi_conn_get_sid(conn);
 834         pdu = (char*)ev + sizeof(*ev);
 835         memcpy(pdu, hdr, sizeof(struct iscsi_hdr));
 836         memcpy(pdu + sizeof(struct iscsi_hdr), data, data_size);
 837
 838         return iscsi_unicast_skb(skb, priv->daemon_pid);
 839 }
 840 EXPORT_SYMBOL_GPL(iscsi_recv_pdu);
 841
 842 void iscsi_conn_error(struct iscsi_cls_conn *conn, enum iscsi_err error)
 843 {
 844         struct nlmsghdr *nlh;
 845         struct sk_buff  *skb;
 846         struct iscsi_uevent *ev;
 847         struct iscsi_internal *priv;
 848         int len = NLMSG_SPACE(sizeof(*ev));
 849
 850         priv = iscsi_if_transport_lookup(conn->transport);
 851         if (!priv)
 852                 return;
 853
 854         skb = alloc_skb(len, GFP_ATOMIC);
 855         if (!skb) {
 856                 iscsi_cls_conn_printk(KERN_ERR, conn, "gracefully ignored "
 857                                       "conn error (%d)\n", error);
 858                 return;
 859         }
 860
 861         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
 862         ev = NLMSG_DATA(nlh);
 863         ev->transport_handle = iscsi_handle(conn->transport);
 864         ev->type = ISCSI_KEVENT_CONN_ERROR;
 865         ev->r.connerror.error = error;
 866         ev->r.connerror.cid = conn->cid;
 867         ev->r.connerror.sid = iscsi_conn_get_sid(conn);
 868
 869         iscsi_broadcast_skb(skb, GFP_ATOMIC);
 870
 871         iscsi_cls_conn_printk(KERN_INFO, conn, "detected conn error (%d)\n",
 872                               error);
 873 }
 874 EXPORT_SYMBOL_GPL(iscsi_conn_error);
 875
 876 static int
 877 iscsi_if_send_reply(int pid, int seq, int type, int done, int multi,
 878                       void *payload, int size)
 879 {
 880         struct sk_buff  *skb;
 881         struct nlmsghdr *nlh;
 882         int len = NLMSG_SPACE(size);
 883         int flags = multi ? NLM_F_MULTI : 0;
 884         int t = done ? NLMSG_DONE : type;
 885
 886         skb = alloc_skb(len, GFP_ATOMIC);
 887         if (!skb) {
 888                 printk(KERN_ERR "Could not allocate skb to send reply.\n");
 889                 return -ENOMEM;
 890         }
 891
 892         nlh = __nlmsg_put(skb, pid, seq, t, (len - sizeof(*nlh)), 0);
 893         nlh->nlmsg_flags = flags;
 894         memcpy(NLMSG_DATA(nlh), payload, size);
 895         return iscsi_unicast_skb(skb, pid);
 896 }
 897
 898 static int
 899 iscsi_if_get_stats(struct iscsi_transport *transport, struct nlmsghdr *nlh)
 900 {
 901         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
 902         struct iscsi_stats *stats;
 903         struct sk_buff *skbstat;
 904         struct iscsi_cls_conn *conn;
 905         struct nlmsghdr *nlhstat;
 906         struct iscsi_uevent *evstat;
 907         struct iscsi_internal *priv;
 908         int len = NLMSG_SPACE(sizeof(*ev) +
 909                               sizeof(struct iscsi_stats) +
 910                               sizeof(struct iscsi_stats_custom) *
 911                               ISCSI_STATS_CUSTOM_MAX);
 912         int err = 0;
 913
 914         priv = iscsi_if_transport_lookup(transport);
 915         if (!priv)
 916                 return -EINVAL;
 917
 918         conn = iscsi_conn_lookup(ev->u.get_stats.sid, ev->u.get_stats.cid);
 919         if (!conn)
 920                 return -EEXIST;
 921
 922         do {
 923                 int actual_size;
 924
 925                 skbstat = alloc_skb(len, GFP_ATOMIC);
 926                 if (!skbstat) {
 927                         iscsi_cls_conn_printk(KERN_ERR, conn, "can not "
 928                                               "deliver stats: OOM\n");
 929                         return -ENOMEM;
 930                 }
 931
 932                 nlhstat = __nlmsg_put(skbstat, priv->daemon_pid, 0, 0,
 933                                       (len - sizeof(*nlhstat)), 0);
 934                 evstat = NLMSG_DATA(nlhstat);
 935                 memset(evstat, 0, sizeof(*evstat));
 936                 evstat->transport_handle = iscsi_handle(conn->transport);
 937                 evstat->type = nlh->nlmsg_type;
 938                 evstat->u.get_stats.cid =
 939                         ev->u.get_stats.cid;
 940                 evstat->u.get_stats.sid =
 941                         ev->u.get_stats.sid;
 942                 stats = (struct iscsi_stats *)
 943                         ((char*)evstat + sizeof(*evstat));
 944                 memset(stats, 0, sizeof(*stats));
 945
 946                 transport->get_stats(conn, stats);
 947                 actual_size = NLMSG_SPACE(sizeof(struct iscsi_uevent) +
 948                                           sizeof(struct iscsi_stats) +
 949                                           sizeof(struct iscsi_stats_custom) *
 950                                           stats->custom_length);
 951                 actual_size -= sizeof(*nlhstat);
 952                 actual_size = NLMSG_LENGTH(actual_size);
 953                 skb_trim(skbstat, NLMSG_ALIGN(actual_size));
 954                 nlhstat->nlmsg_len = actual_size;
 955
 956                 err = iscsi_unicast_skb(skbstat, priv->daemon_pid);
 957         } while (err < 0 && err != -ECONNREFUSED);
 958
 959         return err;
 960 }
 961
 962 /**
 963  * iscsi_session_event - send session destr. completion event
 964  * @session: iscsi class session
 965  * @event: type of event
 966  */
 967 int iscsi_session_event(struct iscsi_cls_session *session,
 968                         enum iscsi_uevent_e event)
 969 {
 970         struct iscsi_internal *priv;
 971         struct Scsi_Host *shost;
 972         struct iscsi_uevent *ev;
 973         struct sk_buff  *skb;
 974         struct nlmsghdr *nlh;
 975         int rc, len = NLMSG_SPACE(sizeof(*ev));
 976
 977         priv = iscsi_if_transport_lookup(session->transport);
 978         if (!priv)
 979                 return -EINVAL;
 980         shost = iscsi_session_to_shost(session);
 981
 982         skb = alloc_skb(len, GFP_KERNEL);
 983         if (!skb) {
 984                 iscsi_cls_session_printk(KERN_ERR, session,
 985                                          "Cannot notify userspace of session "
 986                                          "event %u\n", event);
 987                 return -ENOMEM;
 988         }
 989
 990         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
 991         ev = NLMSG_DATA(nlh);
 992         ev->transport_handle = iscsi_handle(session->transport);
 993
 994         ev->type = event;
 995         switch (event) {
 996         case ISCSI_KEVENT_DESTROY_SESSION:
 997                 ev->r.d_session.host_no = shost->host_no;
 998                 ev->r.d_session.sid = session->sid;
 999                 break;
1000         case ISCSI_KEVENT_CREATE_SESSION:
1001                 ev->r.c_session_ret.host_no = shost->host_no;
1002                 ev->r.c_session_ret.sid = session->sid;
1003                 break;
1004         case ISCSI_KEVENT_UNBIND_SESSION:
1005                 ev->r.unbind_session.host_no = shost->host_no;
1006                 ev->r.unbind_session.sid = session->sid;
1007                 break;
1008         default:
1009                 iscsi_cls_session_printk(KERN_ERR, session, "Invalid event "
1010                                          "%u.\n", event);
1011                 kfree_skb(skb);
1012                 return -EINVAL;
1013         }
1014
1015         /*
1016          * this will occur if the daemon is not up, so we just warn
1017          * the user and when the daemon is restarted it will handle it
1018          */
1019         rc = iscsi_broadcast_skb(skb, GFP_KERNEL);
1020         if (rc < 0)
1021                 iscsi_cls_session_printk(KERN_ERR, session,
1022                                          "Cannot notify userspace of session "
1023                                          "event %u. Check iscsi daemon\n",
1024                                          event);
1025         return rc;
1026 }
1027 EXPORT_SYMBOL_GPL(iscsi_session_event);
1028
1029 static int
1030 iscsi_if_create_session(struct iscsi_internal *priv, struct iscsi_uevent *ev,
1031                         uint32_t host_no, uint32_t initial_cmdsn,
1032                         uint16_t cmds_max, uint16_t queue_depth)
1033 {
1034         struct iscsi_transport *transport = priv->iscsi_transport;
1035         struct iscsi_cls_session *session;
1036         struct Scsi_Host *shost = NULL;
1037
1038         /*
1039          * Software iscsi allocates a host per session, but
1040          * offload drivers (and possibly iser one day) allocate a host per
1041          * hba/nic/rnic. Offload will match a host here, but software will
1042          * return a new hostno after the create_session callback has returned.
1043          */
1044         if (host_no != UINT_MAX) {
1045                 shost = scsi_host_lookup(host_no);
1046                 if (IS_ERR(shost)) {
1047                         printk(KERN_ERR "Could not find host no %u to "
1048                                "create session\n", host_no);
1049                         return -ENODEV;
1050                 }
1051         }
1052
1053         session = transport->create_session(shost, cmds_max, queue_depth,
1054                                             initial_cmdsn, &host_no);
1055         if (shost)
1056                 scsi_host_put(shost);
1057         if (!session)
1058                 return -ENOMEM;
1059
1060         ev->r.c_session_ret.host_no = host_no;
1061         ev->r.c_session_ret.sid = session->sid;
1062         return 0;
1063 }
1064
1065 static int
1066 iscsi_if_create_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1067 {
1068         struct iscsi_cls_conn *conn;
1069         struct iscsi_cls_session *session;
1070
1071         session = iscsi_session_lookup(ev->u.c_conn.sid);
1072         if (!session) {
1073                 printk(KERN_ERR "iscsi: invalid session %d.\n",
1074                        ev->u.c_conn.sid);
1075                 return -EINVAL;
1076         }
1077
1078         conn = transport->create_conn(session, ev->u.c_conn.cid);
1079         if (!conn) {
1080                 iscsi_cls_session_printk(KERN_ERR, session,
1081                                          "couldn't create a new connection.");
1082                 return -ENOMEM;
1083         }
1084
1085         ev->r.c_conn_ret.sid = session->sid;
1086         ev->r.c_conn_ret.cid = conn->cid;
1087         return 0;
1088 }
1089
1090 static int
1091 iscsi_if_destroy_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1092 {
1093         struct iscsi_cls_conn *conn;
1094
1095         conn = iscsi_conn_lookup(ev->u.d_conn.sid, ev->u.d_conn.cid);
1096         if (!conn)
1097                 return -EINVAL;
1098
1099         if (transport->destroy_conn)
1100                 transport->destroy_conn(conn);
1101         return 0;
1102 }
1103
1104 static int
1105 iscsi_set_param(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1106 {
1107         char *data = (char*)ev + sizeof(*ev);
1108         struct iscsi_cls_conn *conn;
1109         struct iscsi_cls_session *session;
1110         int err = 0, value = 0;
1111
1112         session = iscsi_session_lookup(ev->u.set_param.sid);
1113         conn = iscsi_conn_lookup(ev->u.set_param.sid, ev->u.set_param.cid);
1114         if (!conn || !session)
1115                 return -EINVAL;
1116
1117         switch (ev->u.set_param.param) {
1118         case ISCSI_PARAM_SESS_RECOVERY_TMO:
1119                 sscanf(data, "%d", &value);
1120                 if (value != 0)
1121                         session->recovery_tmo = value;
1122                 break;
1123         default:
1124                 err = transport->set_param(conn, ev->u.set_param.param,
1125                                            data, ev->u.set_param.len);
1126         }
1127
1128         return err;
1129 }
1130
1131 static int
1132 iscsi_if_transport_ep(struct iscsi_transport *transport,
1133                       struct iscsi_uevent *ev, int msg_type)
1134 {
1135         struct sockaddr *dst_addr;
1136         int rc = 0;
1137
1138         switch (msg_type) {
1139         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1140                 if (!transport->ep_connect)
1141                         return -EINVAL;
1142
1143                 dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1144                 rc = transport->ep_connect(dst_addr,
1145                                            ev->u.ep_connect.non_blocking,
1146                                            &ev->r.ep_connect_ret.handle);
1147                 break;
1148         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1149                 if (!transport->ep_poll)
1150                         return -EINVAL;
1151
1152                 ev->r.retcode = transport->ep_poll(ev->u.ep_poll.ep_handle,
1153                                                    ev->u.ep_poll.timeout_ms);
1154                 break;
1155         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1156                 if (!transport->ep_disconnect)
1157                         return -EINVAL;
1158
1159                 transport->ep_disconnect(ev->u.ep_disconnect.ep_handle);
1160                 break;
1161         }
1162         return rc;
1163 }
1164
1165 static int
1166 iscsi_tgt_dscvr(struct iscsi_transport *transport,
1167                 struct iscsi_uevent *ev)
1168 {
1169         struct Scsi_Host *shost;
1170         struct sockaddr *dst_addr;
1171         int err;
1172
1173         if (!transport->tgt_dscvr)
1174                 return -EINVAL;
1175
1176         shost = scsi_host_lookup(ev->u.tgt_dscvr.host_no);
1177         if (IS_ERR(shost)) {
1178                 printk(KERN_ERR "target discovery could not find host no %u\n",
1179                        ev->u.tgt_dscvr.host_no);
1180                 return -ENODEV;
1181         }
1182
1183
1184         dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1185         err = transport->tgt_dscvr(shost, ev->u.tgt_dscvr.type,
1186                                    ev->u.tgt_dscvr.enable, dst_addr);
1187         scsi_host_put(shost);
1188         return err;
1189 }
1190
1191 static int
1192 iscsi_set_host_param(struct iscsi_transport *transport,
1193                      struct iscsi_uevent *ev)
1194 {
1195         char *data = (char*)ev + sizeof(*ev);
1196         struct Scsi_Host *shost;
1197         int err;
1198
1199         if (!transport->set_host_param)
1200                 return -ENOSYS;
1201
1202         shost = scsi_host_lookup(ev->u.set_host_param.host_no);
1203         if (IS_ERR(shost)) {
1204                 printk(KERN_ERR "set_host_param could not find host no %u\n",
1205                        ev->u.set_host_param.host_no);
1206                 return -ENODEV;
1207         }
1208
1209         err = transport->set_host_param(shost, ev->u.set_host_param.param,
1210                                         data, ev->u.set_host_param.len);
1211         scsi_host_put(shost);
1212         return err;
1213 }
1214
1215 static int
1216 iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
1217 {
1218         int err = 0;
1219         uint32_t host_no = UINT_MAX;
1220         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1221         struct iscsi_transport *transport = NULL;
1222         struct iscsi_internal *priv;
1223         struct iscsi_cls_session *session;
1224         struct iscsi_cls_conn *conn;
1225
1226         priv = iscsi_if_transport_lookup(iscsi_ptr(ev->transport_handle));
1227         if (!priv)
1228                 return -EINVAL;
1229         transport = priv->iscsi_transport;
1230
1231         if (!try_module_get(transport->owner))
1232                 return -EINVAL;
1233
1234         priv->daemon_pid = NETLINK_CREDS(skb)->pid;
1235
1236         switch (nlh->nlmsg_type) {
1237         case ISCSI_UEVENT_CREATE_SESSION:
1238                 err = iscsi_if_create_session(priv, ev, host_no,
1239                                               ev->u.c_session.initial_cmdsn,
1240                                               ev->u.c_session.cmds_max,
1241                                               ev->u.c_session.queue_depth);
1242                 break;
1243         case ISCSI_UEVENT_CREATE_BOUND_SESSION:
1244                 err = iscsi_if_create_session(priv, ev,
1245                                         ev->u.c_bound_session.host_no,
1246                                         ev->u.c_bound_session.initial_cmdsn,
1247                                         ev->u.c_bound_session.cmds_max,
1248                                         ev->u.c_bound_session.queue_depth);
1249                 break;
1250         case ISCSI_UEVENT_DESTROY_SESSION:
1251                 session = iscsi_session_lookup(ev->u.d_session.sid);
1252                 if (session)
1253                         transport->destroy_session(session);
1254                 else
1255                         err = -EINVAL;
1256                 break;
1257         case ISCSI_UEVENT_UNBIND_SESSION:
1258                 session = iscsi_session_lookup(ev->u.d_session.sid);
1259                 if (session)
1260                         iscsi_unbind_session(session);
1261                 else
1262                         err = -EINVAL;
1263                 break;
1264         case ISCSI_UEVENT_CREATE_CONN:
1265                 err = iscsi_if_create_conn(transport, ev);
1266                 break;
1267         case ISCSI_UEVENT_DESTROY_CONN:
1268                 err = iscsi_if_destroy_conn(transport, ev);
1269                 break;
1270         case ISCSI_UEVENT_BIND_CONN:
1271                 session = iscsi_session_lookup(ev->u.b_conn.sid);
1272                 conn = iscsi_conn_lookup(ev->u.b_conn.sid, ev->u.b_conn.cid);
1273
1274                 if (session && conn)
1275                         ev->r.retcode = transport->bind_conn(session, conn,
1276                                         ev->u.b_conn.transport_eph,
1277                                         ev->u.b_conn.is_leading);
1278                 else
1279                         err = -EINVAL;
1280                 break;
1281         case ISCSI_UEVENT_SET_PARAM:
1282                 err = iscsi_set_param(transport, ev);
1283                 break;
1284         case ISCSI_UEVENT_START_CONN:
1285                 conn = iscsi_conn_lookup(ev->u.start_conn.sid, ev->u.start_conn.cid);
1286                 if (conn)
1287                         ev->r.retcode = transport->start_conn(conn);
1288                 else
1289                         err = -EINVAL;
1290                 break;
1291         case ISCSI_UEVENT_STOP_CONN:
1292                 conn = iscsi_conn_lookup(ev->u.stop_conn.sid, ev->u.stop_conn.cid);
1293                 if (conn)
1294                         transport->stop_conn(conn, ev->u.stop_conn.flag);
1295                 else
1296                         err = -EINVAL;
1297                 break;
1298         case ISCSI_UEVENT_SEND_PDU:
1299                 conn = iscsi_conn_lookup(ev->u.send_pdu.sid, ev->u.send_pdu.cid);
1300                 if (conn)
1301                         ev->r.retcode = transport->send_pdu(conn,
1302                                 (struct iscsi_hdr*)((char*)ev + sizeof(*ev)),
1303                                 (char*)ev + sizeof(*ev) + ev->u.send_pdu.hdr_size,
1304                                 ev->u.send_pdu.data_size);
1305                 else
1306                         err = -EINVAL;
1307                 break;
1308         case ISCSI_UEVENT_GET_STATS:
1309                 err = iscsi_if_get_stats(transport, nlh);
1310                 break;
1311         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1312         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1313         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1314                 err = iscsi_if_transport_ep(transport, ev, nlh->nlmsg_type);
1315                 break;
1316         case ISCSI_UEVENT_TGT_DSCVR:
1317                 err = iscsi_tgt_dscvr(transport, ev);
1318                 break;
1319         case ISCSI_UEVENT_SET_HOST_PARAM:
1320                 err = iscsi_set_host_param(transport, ev);
1321                 break;
1322         default:
1323                 err = -ENOSYS;
1324                 break;
1325         }
1326
1327         module_put(transport->owner);
1328         return err;
1329 }
1330
1331 /*
1332  * Get message from skb.  Each message is processed by iscsi_if_recv_msg.
1333  * Malformed skbs with wrong lengths or invalid creds are not processed.
1334  */
1335 static void
1336 iscsi_if_rx(struct sk_buff *skb)
1337 {
1338         mutex_lock(&rx_queue_mutex);
1339         while (skb->len >= NLMSG_SPACE(0)) {
1340                 int err;
1341                 uint32_t rlen;
1342                 struct nlmsghdr *nlh;
1343                 struct iscsi_uevent *ev;
1344
1345                 nlh = nlmsg_hdr(skb);
1346                 if (nlh->nlmsg_len < sizeof(*nlh) ||
1347                     skb->len < nlh->nlmsg_len) {
1348                         break;
1349                 }
1350
1351                 ev = NLMSG_DATA(nlh);
1352                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1353                 if (rlen > skb->len)
1354                         rlen = skb->len;
1355
1356                 err = iscsi_if_recv_msg(skb, nlh);
1357                 if (err) {
1358                         ev->type = ISCSI_KEVENT_IF_ERROR;
1359                         ev->iferror = err;
1360                 }
1361                 do {
1362                         /*
1363                          * special case for GET_STATS:
1364                          * on success - sending reply and stats from
1365                          * inside of if_recv_msg(),
1366                          * on error - fall through.
1367                          */
1368                         if (ev->type == ISCSI_UEVENT_GET_STATS && !err)
1369                                 break;
1370                         err = iscsi_if_send_reply(
1371                                 NETLINK_CREDS(skb)->pid, nlh->nlmsg_seq,
1372                                 nlh->nlmsg_type, 0, 0, ev, sizeof(*ev));
1373                 } while (err < 0 && err != -ECONNREFUSED);
1374                 skb_pull(skb, rlen);
1375         }
1376         mutex_unlock(&rx_queue_mutex);
1377 }
1378
1379 #define ISCSI_CLASS_ATTR(_prefix,_name,_mode,_show,_store)              \
1380 struct device_attribute dev_attr_##_prefix##_##_name =  \
1381         __ATTR(_name,_mode,_show,_store)
1382
1383 /*
1384  * iSCSI connection attrs
1385  */
1386 #define iscsi_conn_attr_show(param)                                     \
1387 static ssize_t                                                          \
1388 show_conn_param_##param(struct device *dev,                             \
1389                         struct device_attribute *attr, char *buf)       \
1390 {                                                                       \
1391         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev->parent);   \
1392         struct iscsi_transport *t = conn->transport;                    \
1393         return t->get_conn_param(conn, param, buf);                     \
1394 }
1395
1396 #define iscsi_conn_attr(field, param)                                   \
1397         iscsi_conn_attr_show(param)                                     \
1398 static ISCSI_CLASS_ATTR(conn, field, S_IRUGO, show_conn_param_##param,  \
1399                         NULL);
1400
1401 iscsi_conn_attr(max_recv_dlength, ISCSI_PARAM_MAX_RECV_DLENGTH);
1402 iscsi_conn_attr(max_xmit_dlength, ISCSI_PARAM_MAX_XMIT_DLENGTH);
1403 iscsi_conn_attr(header_digest, ISCSI_PARAM_HDRDGST_EN);
1404 iscsi_conn_attr(data_digest, ISCSI_PARAM_DATADGST_EN);
1405 iscsi_conn_attr(ifmarker, ISCSI_PARAM_IFMARKER_EN);
1406 iscsi_conn_attr(ofmarker, ISCSI_PARAM_OFMARKER_EN);
1407 iscsi_conn_attr(persistent_port, ISCSI_PARAM_PERSISTENT_PORT);
1408 iscsi_conn_attr(port, ISCSI_PARAM_CONN_PORT);
1409 iscsi_conn_attr(exp_statsn, ISCSI_PARAM_EXP_STATSN);
1410 iscsi_conn_attr(persistent_address, ISCSI_PARAM_PERSISTENT_ADDRESS);
1411 iscsi_conn_attr(address, ISCSI_PARAM_CONN_ADDRESS);
1412 iscsi_conn_attr(ping_tmo, ISCSI_PARAM_PING_TMO);
1413 iscsi_conn_attr(recv_tmo, ISCSI_PARAM_RECV_TMO);
1414
1415 /*
1416  * iSCSI session attrs
1417  */
1418 #define iscsi_session_attr_show(param, perm)                            \
1419 static ssize_t                                                          \
1420 show_session_param_##param(struct device *dev,                          \
1421                            struct device_attribute *attr, char *buf)    \
1422 {                                                                       \
1423         struct iscsi_cls_session *session =                             \
1424                 iscsi_dev_to_session(dev->parent);                      \
1425         struct iscsi_transport *t = session->transport;                 \
1426                                                                         \
1427         if (perm && !capable(CAP_SYS_ADMIN))                            \
1428                 return -EACCES;                                         \
1429         return t->get_session_param(session, param, buf);               \
1430 }
1431
1432 #define iscsi_session_attr(field, param, perm)                          \
1433         iscsi_session_attr_show(param, perm)                            \
1434 static ISCSI_CLASS_ATTR(sess, field, S_IRUGO, show_session_param_##param, \
1435                         NULL);
1436
1437 iscsi_session_attr(targetname, ISCSI_PARAM_TARGET_NAME, 0);
1438 iscsi_session_attr(initial_r2t, ISCSI_PARAM_INITIAL_R2T_EN, 0);
1439 iscsi_session_attr(max_outstanding_r2t, ISCSI_PARAM_MAX_R2T, 0);
1440 iscsi_session_attr(immediate_data, ISCSI_PARAM_IMM_DATA_EN, 0);
1441 iscsi_session_attr(first_burst_len, ISCSI_PARAM_FIRST_BURST, 0);
1442 iscsi_session_attr(max_burst_len, ISCSI_PARAM_MAX_BURST, 0);
1443 iscsi_session_attr(data_pdu_in_order, ISCSI_PARAM_PDU_INORDER_EN, 0);
1444 iscsi_session_attr(data_seq_in_order, ISCSI_PARAM_DATASEQ_INORDER_EN, 0);
1445 iscsi_session_attr(erl, ISCSI_PARAM_ERL, 0);
1446 iscsi_session_attr(tpgt, ISCSI_PARAM_TPGT, 0);
1447 iscsi_session_attr(username, ISCSI_PARAM_USERNAME, 1);
1448 iscsi_session_attr(username_in, ISCSI_PARAM_USERNAME_IN, 1);
1449 iscsi_session_attr(password, ISCSI_PARAM_PASSWORD, 1);
1450 iscsi_session_attr(password_in, ISCSI_PARAM_PASSWORD_IN, 1);
1451 iscsi_session_attr(fast_abort, ISCSI_PARAM_FAST_ABORT, 0);
1452 iscsi_session_attr(abort_tmo, ISCSI_PARAM_ABORT_TMO, 0);
1453 iscsi_session_attr(lu_reset_tmo, ISCSI_PARAM_LU_RESET_TMO, 0);
1454
1455 static ssize_t
1456 show_priv_session_state(struct device *dev, struct device_attribute *attr,
1457                         char *buf)
1458 {
1459         struct iscsi_cls_session *session = iscsi_dev_to_session(dev->parent);
1460         return sprintf(buf, "%s\n", iscsi_session_state_name(session->state));
1461 }
1462 static ISCSI_CLASS_ATTR(priv_sess, state, S_IRUGO, show_priv_session_state,
1463                         NULL);
1464
1465 #define iscsi_priv_session_attr_show(field, format)                     \
1466 static ssize_t                                                          \
1467 show_priv_session_##field(struct device *dev,                           \
1468                           struct device_attribute *attr, char *buf)     \
1469 {                                                                       \
1470         struct iscsi_cls_session *session =                             \
1471                         iscsi_dev_to_session(dev->parent);              \
1472         return sprintf(buf, format"\n", session->field);                \
1473 }
1474
1475 #define iscsi_priv_session_attr(field, format)                          \
1476         iscsi_priv_session_attr_show(field, format)                     \
1477 static ISCSI_CLASS_ATTR(priv_sess, field, S_IRUGO, show_priv_session_##field, \
1478                         NULL)
1479 iscsi_priv_session_attr(recovery_tmo, "%d");
1480
1481 /*
1482  * iSCSI host attrs
1483  */
1484 #define iscsi_host_attr_show(param)                                     \
1485 static ssize_t                                                          \
1486 show_host_param_##param(struct device *dev,                             \
1487                         struct device_attribute *attr, char *buf)       \
1488 {                                                                       \
1489         struct Scsi_Host *shost = transport_class_to_shost(dev);        \
1490         struct iscsi_internal *priv = to_iscsi_internal(shost->transportt); \
1491         return priv->iscsi_transport->get_host_param(shost, param, buf); \
1492 }
1493
1494 #define iscsi_host_attr(field, param)                                   \
1495         iscsi_host_attr_show(param)                                     \
1496 static ISCSI_CLASS_ATTR(host, field, S_IRUGO, show_host_param_##param,  \
1497                         NULL);
1498
1499 iscsi_host_attr(netdev, ISCSI_HOST_PARAM_NETDEV_NAME);
1500 iscsi_host_attr(hwaddress, ISCSI_HOST_PARAM_HWADDRESS);
1501 iscsi_host_attr(ipaddress, ISCSI_HOST_PARAM_IPADDRESS);
1502 iscsi_host_attr(initiatorname, ISCSI_HOST_PARAM_INITIATOR_NAME);
1503
1504 #define SETUP_PRIV_SESSION_RD_ATTR(field)                               \
1505 do {                                                                    \
1506         priv->session_attrs[count] = &dev_attr_priv_sess_##field; \
1507         count++;                                                        \
1508 } while (0)
1509
1510
1511 #define SETUP_SESSION_RD_ATTR(field, param_flag)                        \
1512 do {                                                                    \
1513         if (tt->param_mask & param_flag) {                              \
1514                 priv->session_attrs[count] = &dev_attr_sess_##field; \
1515                 count++;                                                \
1516         }                                                               \
1517 } while (0)
1518
1519 #define SETUP_CONN_RD_ATTR(field, param_flag)                           \
1520 do {                                                                    \
1521         if (tt->param_mask & param_flag) {                              \
1522                 priv->conn_attrs[count] = &dev_attr_conn_##field; \
1523                 count++;                                                \
1524         }                                                               \
1525 } while (0)
1526
1527 #define SETUP_HOST_RD_ATTR(field, param_flag)                           \
1528 do {                                                                    \
1529         if (tt->host_param_mask & param_flag) {                         \
1530                 priv->host_attrs[count] = &dev_attr_host_##field; \
1531                 count++;                                                \
1532         }                                                               \
1533 } while (0)
1534
1535 static int iscsi_session_match(struct attribute_container *cont,
1536                            struct device *dev)
1537 {
1538         struct iscsi_cls_session *session;
1539         struct Scsi_Host *shost;
1540         struct iscsi_internal *priv;
1541
1542         if (!iscsi_is_session_dev(dev))
1543                 return 0;
1544
1545         session = iscsi_dev_to_session(dev);
1546         shost = iscsi_session_to_shost(session);
1547         if (!shost->transportt)
1548                 return 0;
1549
1550         priv = to_iscsi_internal(shost->transportt);
1551         if (priv->session_cont.ac.class != &iscsi_session_class.class)
1552                 return 0;
1553
1554         return &priv->session_cont.ac == cont;
1555 }
1556
1557 static int iscsi_conn_match(struct attribute_container *cont,
1558                            struct device *dev)
1559 {
1560         struct iscsi_cls_session *session;
1561         struct iscsi_cls_conn *conn;
1562         struct Scsi_Host *shost;
1563         struct iscsi_internal *priv;
1564
1565         if (!iscsi_is_conn_dev(dev))
1566                 return 0;
1567
1568         conn = iscsi_dev_to_conn(dev);
1569         session = iscsi_dev_to_session(conn->dev.parent);
1570         shost = iscsi_session_to_shost(session);
1571
1572         if (!shost->transportt)
1573                 return 0;
1574
1575         priv = to_iscsi_internal(shost->transportt);
1576         if (priv->conn_cont.ac.class != &iscsi_connection_class.class)
1577                 return 0;
1578
1579         return &priv->conn_cont.ac == cont;
1580 }
1581
1582 static int iscsi_host_match(struct attribute_container *cont,
1583                             struct device *dev)
1584 {
1585         struct Scsi_Host *shost;
1586         struct iscsi_internal *priv;
1587
1588         if (!scsi_is_host_device(dev))
1589                 return 0;
1590
1591         shost = dev_to_shost(dev);
1592         if (!shost->transportt  ||
1593             shost->transportt->host_attrs.ac.class != &iscsi_host_class.class)
1594                 return 0;
1595
1596         priv = to_iscsi_internal(shost->transportt);
1597         return &priv->t.host_attrs.ac == cont;
1598 }
1599
1600 struct scsi_transport_template *
1601 iscsi_register_transport(struct iscsi_transport *tt)
1602 {
1603         struct iscsi_internal *priv;
1604         unsigned long flags;
1605         int count = 0, err;
1606
1607         BUG_ON(!tt);
1608
1609         priv = iscsi_if_transport_lookup(tt);
1610         if (priv)
1611                 return NULL;
1612
1613         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1614         if (!priv)
1615                 return NULL;
1616         INIT_LIST_HEAD(&priv->list);
1617         priv->daemon_pid = -1;
1618         priv->iscsi_transport = tt;
1619         priv->t.user_scan = iscsi_user_scan;
1620         if (!(tt->caps & CAP_DATA_PATH_OFFLOAD))
1621                 priv->t.create_work_queue = 1;
1622
1623         priv->dev.class = &iscsi_transport_class;
1624         snprintf(priv->dev.bus_id, BUS_ID_SIZE, "%s", tt->name);
1625         err = device_register(&priv->dev);
1626         if (err)
1627                 goto free_priv;
1628
1629         err = sysfs_create_group(&priv->dev.kobj, &iscsi_transport_group);
1630         if (err)
1631                 goto unregister_dev;
1632
1633         /* host parameters */
1634         priv->t.host_attrs.ac.attrs = &priv->host_attrs[0];
1635         priv->t.host_attrs.ac.class = &iscsi_host_class.class;
1636         priv->t.host_attrs.ac.match = iscsi_host_match;
1637         priv->t.host_size = sizeof(struct iscsi_cls_host);
1638         transport_container_register(&priv->t.host_attrs);
1639
1640         SETUP_HOST_RD_ATTR(netdev, ISCSI_HOST_NETDEV_NAME);
1641         SETUP_HOST_RD_ATTR(ipaddress, ISCSI_HOST_IPADDRESS);
1642         SETUP_HOST_RD_ATTR(hwaddress, ISCSI_HOST_HWADDRESS);
1643         SETUP_HOST_RD_ATTR(initiatorname, ISCSI_HOST_INITIATOR_NAME);
1644         BUG_ON(count > ISCSI_HOST_ATTRS);
1645         priv->host_attrs[count] = NULL;
1646         count = 0;
1647
1648         /* connection parameters */
1649         priv->conn_cont.ac.attrs = &priv->conn_attrs[0];
1650         priv->conn_cont.ac.class = &iscsi_connection_class.class;
1651         priv->conn_cont.ac.match = iscsi_conn_match;
1652         transport_container_register(&priv->conn_cont);
1653
1654         SETUP_CONN_RD_ATTR(max_recv_dlength, ISCSI_MAX_RECV_DLENGTH);
1655         SETUP_CONN_RD_ATTR(max_xmit_dlength, ISCSI_MAX_XMIT_DLENGTH);
1656         SETUP_CONN_RD_ATTR(header_digest, ISCSI_HDRDGST_EN);
1657         SETUP_CONN_RD_ATTR(data_digest, ISCSI_DATADGST_EN);
1658         SETUP_CONN_RD_ATTR(ifmarker, ISCSI_IFMARKER_EN);
1659         SETUP_CONN_RD_ATTR(ofmarker, ISCSI_OFMARKER_EN);
1660         SETUP_CONN_RD_ATTR(address, ISCSI_CONN_ADDRESS);
1661         SETUP_CONN_RD_ATTR(port, ISCSI_CONN_PORT);
1662         SETUP_CONN_RD_ATTR(exp_statsn, ISCSI_EXP_STATSN);
1663         SETUP_CONN_RD_ATTR(persistent_address, ISCSI_PERSISTENT_ADDRESS);
1664         SETUP_CONN_RD_ATTR(persistent_port, ISCSI_PERSISTENT_PORT);
1665         SETUP_CONN_RD_ATTR(ping_tmo, ISCSI_PING_TMO);
1666         SETUP_CONN_RD_ATTR(recv_tmo, ISCSI_RECV_TMO);
1667
1668         BUG_ON(count > ISCSI_CONN_ATTRS);
1669         priv->conn_attrs[count] = NULL;
1670         count = 0;
1671
1672         /* session parameters */
1673         priv->session_cont.ac.attrs = &priv->session_attrs[0];
1674         priv->session_cont.ac.class = &iscsi_session_class.class;
1675         priv->session_cont.ac.match = iscsi_session_match;
1676         transport_container_register(&priv->session_cont);
1677
1678         SETUP_SESSION_RD_ATTR(initial_r2t, ISCSI_INITIAL_R2T_EN);
1679         SETUP_SESSION_RD_ATTR(max_outstanding_r2t, ISCSI_MAX_R2T);
1680         SETUP_SESSION_RD_ATTR(immediate_data, ISCSI_IMM_DATA_EN);
1681         SETUP_SESSION_RD_ATTR(first_burst_len, ISCSI_FIRST_BURST);
1682         SETUP_SESSION_RD_ATTR(max_burst_len, ISCSI_MAX_BURST);
1683         SETUP_SESSION_RD_ATTR(data_pdu_in_order, ISCSI_PDU_INORDER_EN);
1684         SETUP_SESSION_RD_ATTR(data_seq_in_order, ISCSI_DATASEQ_INORDER_EN);
1685         SETUP_SESSION_RD_ATTR(erl, ISCSI_ERL);
1686         SETUP_SESSION_RD_ATTR(targetname, ISCSI_TARGET_NAME);
1687         SETUP_SESSION_RD_ATTR(tpgt, ISCSI_TPGT);
1688         SETUP_SESSION_RD_ATTR(password, ISCSI_USERNAME);
1689         SETUP_SESSION_RD_ATTR(password_in, ISCSI_USERNAME_IN);
1690         SETUP_SESSION_RD_ATTR(username, ISCSI_PASSWORD);
1691         SETUP_SESSION_RD_ATTR(username_in, ISCSI_PASSWORD_IN);
1692         SETUP_SESSION_RD_ATTR(fast_abort, ISCSI_FAST_ABORT);
1693         SETUP_SESSION_RD_ATTR(abort_tmo, ISCSI_ABORT_TMO);
1694         SETUP_SESSION_RD_ATTR(lu_reset_tmo,ISCSI_LU_RESET_TMO);
1695         SETUP_PRIV_SESSION_RD_ATTR(recovery_tmo);
1696         SETUP_PRIV_SESSION_RD_ATTR(state);
1697
1698         BUG_ON(count > ISCSI_SESSION_ATTRS);
1699         priv->session_attrs[count] = NULL;
1700
1701         spin_lock_irqsave(&iscsi_transport_lock, flags);
1702         list_add(&priv->list, &iscsi_transports);
1703         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1704
1705         printk(KERN_NOTICE "iscsi: registered transport (%s)\n", tt->name);
1706         return &priv->t;
1707
1708 unregister_dev:
1709         device_unregister(&priv->dev);
1710 free_priv:
1711         kfree(priv);
1712         return NULL;
1713 }
1714 EXPORT_SYMBOL_GPL(iscsi_register_transport);
1715
1716 int iscsi_unregister_transport(struct iscsi_transport *tt)
1717 {
1718         struct iscsi_internal *priv;
1719         unsigned long flags;
1720
1721         BUG_ON(!tt);
1722
1723         mutex_lock(&rx_queue_mutex);
1724
1725         priv = iscsi_if_transport_lookup(tt);
1726         BUG_ON (!priv);
1727
1728         spin_lock_irqsave(&iscsi_transport_lock, flags);
1729         list_del(&priv->list);
1730         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1731
1732         transport_container_unregister(&priv->conn_cont);
1733         transport_container_unregister(&priv->session_cont);
1734         transport_container_unregister(&priv->t.host_attrs);
1735
1736         sysfs_remove_group(&priv->dev.kobj, &iscsi_transport_group);
1737         device_unregister(&priv->dev);
1738         mutex_unlock(&rx_queue_mutex);
1739
1740         return 0;
1741 }
1742 EXPORT_SYMBOL_GPL(iscsi_unregister_transport);
1743
1744 static __init int iscsi_transport_init(void)
1745 {
1746         int err;
1747
1748         printk(KERN_INFO "Loading iSCSI transport class v%s.\n",
1749                 ISCSI_TRANSPORT_VERSION);
1750
1751         atomic_set(&iscsi_session_nr, 0);
1752
1753         err = class_register(&iscsi_transport_class);
1754         if (err)
1755                 return err;
1756
1757         err = transport_class_register(&iscsi_host_class);
1758         if (err)
1759                 goto unregister_transport_class;
1760
1761         err = transport_class_register(&iscsi_connection_class);
1762         if (err)
1763                 goto unregister_host_class;
1764
1765         err = transport_class_register(&iscsi_session_class);
1766         if (err)
1767                 goto unregister_conn_class;
1768
1769         nls = netlink_kernel_create(&init_net, NETLINK_ISCSI, 1, iscsi_if_rx, NULL,
1770                         THIS_MODULE);
1771         if (!nls) {
1772                 err = -ENOBUFS;
1773                 goto unregister_session_class;
1774         }
1775
1776         iscsi_eh_timer_workq = create_singlethread_workqueue("iscsi_eh");
1777         if (!iscsi_eh_timer_workq)
1778                 goto release_nls;
1779
1780         return 0;
1781
1782 release_nls:
1783         netlink_kernel_release(nls);
1784 unregister_session_class:
1785         transport_class_unregister(&iscsi_session_class);
1786 unregister_conn_class:
1787         transport_class_unregister(&iscsi_connection_class);
1788 unregister_host_class:
1789         transport_class_unregister(&iscsi_host_class);
1790 unregister_transport_class:
1791         class_unregister(&iscsi_transport_class);
1792         return err;
1793 }
1794
1795 static void __exit iscsi_transport_exit(void)
1796 {
1797         destroy_workqueue(iscsi_eh_timer_workq);
1798         netlink_kernel_release(nls);
1799         transport_class_unregister(&iscsi_connection_class);
1800         transport_class_unregister(&iscsi_session_class);
1801         transport_class_unregister(&iscsi_host_class);
1802         class_unregister(&iscsi_transport_class);
1803 }
1804
1805 module_init(iscsi_transport_init);
1806 module_exit(iscsi_transport_exit);
1807
1808 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
1809               "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
1810               "Alex Aizman <itn780@yahoo.com>");
1811 MODULE_DESCRIPTION("iSCSI Transport Interface");
1812 MODULE_LICENSE("GPL");
1813 MODULE_VERSION(ISCSI_TRANSPORT_VERSION);