git.oblomov.eu Git - 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 21
  34 #define ISCSI_CONN_ATTRS 13
  35 #define ISCSI_HOST_ATTRS 4
  36
  37 #define ISCSI_TRANSPORT_VERSION "2.0-869"
  38
  39 struct iscsi_internal {
  40         int daemon_pid;
  41         struct scsi_transport_template t;
  42         struct iscsi_transport *iscsi_transport;
  43         struct list_head list;
  44         struct device dev;
  45
  46         struct device_attribute *host_attrs[ISCSI_HOST_ATTRS + 1];
  47         struct transport_container conn_cont;
  48         struct device_attribute *conn_attrs[ISCSI_CONN_ATTRS + 1];
  49         struct transport_container session_cont;
  50         struct device_attribute *session_attrs[ISCSI_SESSION_ATTRS + 1];
  51 };
  52
  53 static atomic_t iscsi_session_nr; /* sysfs session id for next new session */
  54 static struct workqueue_struct *iscsi_eh_timer_workq;
  55
  56 /*
  57  * list of registered transports and lock that must
  58  * be held while accessing list. The iscsi_transport_lock must
  59  * be acquired after the rx_queue_mutex.
  60  */
  61 static LIST_HEAD(iscsi_transports);
  62 static DEFINE_SPINLOCK(iscsi_transport_lock);
  63
  64 #define to_iscsi_internal(tmpl) \
  65         container_of(tmpl, struct iscsi_internal, t)
  66
  67 #define dev_to_iscsi_internal(_dev) \
  68         container_of(_dev, struct iscsi_internal, dev)
  69
  70 static void iscsi_transport_release(struct device *dev)
  71 {
  72         struct iscsi_internal *priv = dev_to_iscsi_internal(dev);
  73         kfree(priv);
  74 }
  75
  76 /*
  77  * iscsi_transport_class represents the iscsi_transports that are
  78  * registered.
  79  */
  80 static struct class iscsi_transport_class = {
  81         .name = "iscsi_transport",
  82         .dev_release = iscsi_transport_release,
  83 };
  84
  85 static ssize_t
  86 show_transport_handle(struct device *dev, struct device_attribute *attr,
  87                       char *buf)
  88 {
  89         struct iscsi_internal *priv = dev_to_iscsi_internal(dev);
  90         return sprintf(buf, "%llu\n", (unsigned long long)iscsi_handle(priv->iscsi_transport));
  91 }
  92 static DEVICE_ATTR(handle, S_IRUGO, show_transport_handle, NULL);
  93
  94 #define show_transport_attr(name, format)                               \
  95 static ssize_t                                                          \
  96 show_transport_##name(struct device *dev,                               \
  97                       struct device_attribute *attr,char *buf)          \
  98 {                                                                       \
  99         struct iscsi_internal *priv = dev_to_iscsi_internal(dev);       \
 100         return sprintf(buf, format"\n", priv->iscsi_transport->name);   \
 101 }                                                                       \
 102 static DEVICE_ATTR(name, S_IRUGO, show_transport_##name, NULL);
 103
 104 show_transport_attr(caps, "0x%x");
 105
 106 static struct attribute *iscsi_transport_attrs[] = {
 107         &dev_attr_handle.attr,
 108         &dev_attr_caps.attr,
 109         NULL,
 110 };
 111
 112 static struct attribute_group iscsi_transport_group = {
 113         .attrs = iscsi_transport_attrs,
 114 };
 115
 116 /*
 117  * iSCSI endpoint attrs
 118  */
 119 #define iscsi_dev_to_endpoint(_dev) \
 120         container_of(_dev, struct iscsi_endpoint, dev)
 121
 122 #define ISCSI_ATTR(_prefix,_name,_mode,_show,_store)    \
 123 struct device_attribute dev_attr_##_prefix##_##_name =  \
 124         __ATTR(_name,_mode,_show,_store)
 125
 126 static void iscsi_endpoint_release(struct device *dev)
 127 {
 128         struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
 129         kfree(ep);
 130 }
 131
 132 static struct class iscsi_endpoint_class = {
 133         .name = "iscsi_endpoint",
 134         .dev_release = iscsi_endpoint_release,
 135 };
 136
 137 static ssize_t
 138 show_ep_handle(struct device *dev, struct device_attribute *attr, char *buf)
 139 {
 140         struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
 141         return sprintf(buf, "%u\n", ep->id);
 142 }
 143 static ISCSI_ATTR(ep, handle, S_IRUGO, show_ep_handle, NULL);
 144
 145 static struct attribute *iscsi_endpoint_attrs[] = {
 146         &dev_attr_ep_handle.attr,
 147         NULL,
 148 };
 149
 150 static struct attribute_group iscsi_endpoint_group = {
 151         .attrs = iscsi_endpoint_attrs,
 152 };
 153
 154 #define ISCSI_MAX_EPID -1
 155
 156 static int iscsi_match_epid(struct device *dev, void *data)
 157 {
 158         struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
 159         unsigned int *epid = (unsigned int *) data;
 160
 161         return *epid == ep->id;
 162 }
 163
 164 struct iscsi_endpoint *
 165 iscsi_create_endpoint(int dd_size)
 166 {
 167         struct device *dev;
 168         struct iscsi_endpoint *ep;
 169         unsigned int id;
 170         int err;
 171
 172         for (id = 1; id < ISCSI_MAX_EPID; id++) {
 173                 dev = class_find_device(&iscsi_endpoint_class, &id,
 174                                         iscsi_match_epid);
 175                 if (!dev)
 176                         break;
 177         }
 178         if (id == ISCSI_MAX_EPID) {
 179                 printk(KERN_ERR "Too many connections. Max supported %u\n",
 180                        ISCSI_MAX_EPID - 1);
 181                 return NULL;
 182         }
 183
 184         ep = kzalloc(sizeof(*ep) + dd_size, GFP_KERNEL);
 185         if (!ep)
 186                 return NULL;
 187
 188         ep->id = id;
 189         ep->dev.class = &iscsi_endpoint_class;
 190         snprintf(ep->dev.bus_id, BUS_ID_SIZE, "ep-%u", id);
 191         err = device_register(&ep->dev);
 192         if (err)
 193                 goto free_ep;
 194
 195         err = sysfs_create_group(&ep->dev.kobj, &iscsi_endpoint_group);
 196         if (err)
 197                 goto unregister_dev;
 198
 199         if (dd_size)
 200                 ep->dd_data = &ep[1];
 201         return ep;
 202
 203 unregister_dev:
 204         device_unregister(&ep->dev);
 205         return NULL;
 206
 207 free_ep:
 208         kfree(ep);
 209         return NULL;
 210 }
 211 EXPORT_SYMBOL_GPL(iscsi_create_endpoint);
 212
 213 void iscsi_destroy_endpoint(struct iscsi_endpoint *ep)
 214 {
 215         sysfs_remove_group(&ep->dev.kobj, &iscsi_endpoint_group);
 216         device_unregister(&ep->dev);
 217 }
 218 EXPORT_SYMBOL_GPL(iscsi_destroy_endpoint);
 219
 220 struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle)
 221 {
 222         struct device *dev;
 223
 224         dev = class_find_device(&iscsi_endpoint_class, &handle,
 225                                 iscsi_match_epid);
 226         if (!dev)
 227                 return NULL;
 228
 229         return iscsi_dev_to_endpoint(dev);
 230 }
 231 EXPORT_SYMBOL_GPL(iscsi_lookup_endpoint);
 232
 233 static int iscsi_setup_host(struct transport_container *tc, struct device *dev,
 234                             struct device *cdev)
 235 {
 236         struct Scsi_Host *shost = dev_to_shost(dev);
 237         struct iscsi_cls_host *ihost = shost->shost_data;
 238
 239         memset(ihost, 0, sizeof(*ihost));
 240         atomic_set(&ihost->nr_scans, 0);
 241         mutex_init(&ihost->mutex);
 242
 243         snprintf(ihost->scan_workq_name, KOBJ_NAME_LEN, "iscsi_scan_%d",
 244                 shost->host_no);
 245         ihost->scan_workq = create_singlethread_workqueue(
 246                                                 ihost->scan_workq_name);
 247         if (!ihost->scan_workq)
 248                 return -ENOMEM;
 249         return 0;
 250 }
 251
 252 static int iscsi_remove_host(struct transport_container *tc, struct device *dev,
 253                              struct device *cdev)
 254 {
 255         struct Scsi_Host *shost = dev_to_shost(dev);
 256         struct iscsi_cls_host *ihost = shost->shost_data;
 257
 258         destroy_workqueue(ihost->scan_workq);
 259         return 0;
 260 }
 261
 262 static DECLARE_TRANSPORT_CLASS(iscsi_host_class,
 263                                "iscsi_host",
 264                                iscsi_setup_host,
 265                                iscsi_remove_host,
 266                                NULL);
 267
 268 static DECLARE_TRANSPORT_CLASS(iscsi_session_class,
 269                                "iscsi_session",
 270                                NULL,
 271                                NULL,
 272                                NULL);
 273
 274 static DECLARE_TRANSPORT_CLASS(iscsi_connection_class,
 275                                "iscsi_connection",
 276                                NULL,
 277                                NULL,
 278                                NULL);
 279
 280 static struct sock *nls;
 281 static DEFINE_MUTEX(rx_queue_mutex);
 282
 283 static LIST_HEAD(sesslist);
 284 static DEFINE_SPINLOCK(sesslock);
 285 static LIST_HEAD(connlist);
 286 static DEFINE_SPINLOCK(connlock);
 287
 288 static uint32_t iscsi_conn_get_sid(struct iscsi_cls_conn *conn)
 289 {
 290         struct iscsi_cls_session *sess = iscsi_dev_to_session(conn->dev.parent);
 291         return sess->sid;
 292 }
 293
 294 /*
 295  * Returns the matching session to a given sid
 296  */
 297 static struct iscsi_cls_session *iscsi_session_lookup(uint32_t sid)
 298 {
 299         unsigned long flags;
 300         struct iscsi_cls_session *sess;
 301
 302         spin_lock_irqsave(&sesslock, flags);
 303         list_for_each_entry(sess, &sesslist, sess_list) {
 304                 if (sess->sid == sid) {
 305                         spin_unlock_irqrestore(&sesslock, flags);
 306                         return sess;
 307                 }
 308         }
 309         spin_unlock_irqrestore(&sesslock, flags);
 310         return NULL;
 311 }
 312
 313 /*
 314  * Returns the matching connection to a given sid / cid tuple
 315  */
 316 static struct iscsi_cls_conn *iscsi_conn_lookup(uint32_t sid, uint32_t cid)
 317 {
 318         unsigned long flags;
 319         struct iscsi_cls_conn *conn;
 320
 321         spin_lock_irqsave(&connlock, flags);
 322         list_for_each_entry(conn, &connlist, conn_list) {
 323                 if ((conn->cid == cid) && (iscsi_conn_get_sid(conn) == sid)) {
 324                         spin_unlock_irqrestore(&connlock, flags);
 325                         return conn;
 326                 }
 327         }
 328         spin_unlock_irqrestore(&connlock, flags);
 329         return NULL;
 330 }
 331
 332 /*
 333  * The following functions can be used by LLDs that allocate
 334  * their own scsi_hosts or by software iscsi LLDs
 335  */
 336 static struct {
 337         int value;
 338         char *name;
 339 } iscsi_session_state_names[] = {
 340         { ISCSI_SESSION_LOGGED_IN,      "LOGGED_IN" },
 341         { ISCSI_SESSION_FAILED,         "FAILED" },
 342         { ISCSI_SESSION_FREE,           "FREE" },
 343 };
 344
 345 static const char *iscsi_session_state_name(int state)
 346 {
 347         int i;
 348         char *name = NULL;
 349
 350         for (i = 0; i < ARRAY_SIZE(iscsi_session_state_names); i++) {
 351                 if (iscsi_session_state_names[i].value == state) {
 352                         name = iscsi_session_state_names[i].name;
 353                         break;
 354                 }
 355         }
 356         return name;
 357 }
 358
 359 int iscsi_session_chkready(struct iscsi_cls_session *session)
 360 {
 361         unsigned long flags;
 362         int err;
 363
 364         spin_lock_irqsave(&session->lock, flags);
 365         switch (session->state) {
 366         case ISCSI_SESSION_LOGGED_IN:
 367                 err = 0;
 368                 break;
 369         case ISCSI_SESSION_FAILED:
 370                 err = DID_IMM_RETRY << 16;
 371                 break;
 372         case ISCSI_SESSION_FREE:
 373                 err = DID_NO_CONNECT << 16;
 374                 break;
 375         default:
 376                 err = DID_NO_CONNECT << 16;
 377                 break;
 378         }
 379         spin_unlock_irqrestore(&session->lock, flags);
 380         return err;
 381 }
 382 EXPORT_SYMBOL_GPL(iscsi_session_chkready);
 383
 384 static void iscsi_session_release(struct device *dev)
 385 {
 386         struct iscsi_cls_session *session = iscsi_dev_to_session(dev);
 387         struct Scsi_Host *shost;
 388
 389         shost = iscsi_session_to_shost(session);
 390         scsi_host_put(shost);
 391         kfree(session);
 392 }
 393
 394 static int iscsi_is_session_dev(const struct device *dev)
 395 {
 396         return dev->release == iscsi_session_release;
 397 }
 398
 399 static int iscsi_iter_session_fn(struct device *dev, void *data)
 400 {
 401         void (* fn) (struct iscsi_cls_session *) = data;
 402
 403         if (!iscsi_is_session_dev(dev))
 404                 return 0;
 405         fn(iscsi_dev_to_session(dev));
 406         return 0;
 407 }
 408
 409 void iscsi_host_for_each_session(struct Scsi_Host *shost,
 410                                  void (*fn)(struct iscsi_cls_session *))
 411 {
 412         device_for_each_child(&shost->shost_gendev, fn,
 413                               iscsi_iter_session_fn);
 414 }
 415 EXPORT_SYMBOL_GPL(iscsi_host_for_each_session);
 416
 417 /**
 418  * iscsi_scan_finished - helper to report when running scans are done
 419  * @shost: scsi host
 420  * @time: scan run time
 421  *
 422  * This function can be used by drives like qla4xxx to report to the scsi
 423  * layer when the scans it kicked off at module load time are done.
 424  */
 425 int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time)
 426 {
 427         struct iscsi_cls_host *ihost = shost->shost_data;
 428         /*
 429          * qla4xxx will have kicked off some session unblocks before calling
 430          * scsi_scan_host, so just wait for them to complete.
 431          */
 432         return !atomic_read(&ihost->nr_scans);
 433 }
 434 EXPORT_SYMBOL_GPL(iscsi_scan_finished);
 435
 436 struct iscsi_scan_data {
 437         unsigned int channel;
 438         unsigned int id;
 439         unsigned int lun;
 440 };
 441
 442 static int iscsi_user_scan_session(struct device *dev, void *data)
 443 {
 444         struct iscsi_scan_data *scan_data = data;
 445         struct iscsi_cls_session *session;
 446         struct Scsi_Host *shost;
 447         struct iscsi_cls_host *ihost;
 448         unsigned long flags;
 449         unsigned int id;
 450
 451         if (!iscsi_is_session_dev(dev))
 452                 return 0;
 453
 454         session = iscsi_dev_to_session(dev);
 455         shost = iscsi_session_to_shost(session);
 456         ihost = shost->shost_data;
 457
 458         mutex_lock(&ihost->mutex);
 459         spin_lock_irqsave(&session->lock, flags);
 460         if (session->state != ISCSI_SESSION_LOGGED_IN) {
 461                 spin_unlock_irqrestore(&session->lock, flags);
 462                 mutex_unlock(&ihost->mutex);
 463                 return 0;
 464         }
 465         id = session->target_id;
 466         spin_unlock_irqrestore(&session->lock, flags);
 467
 468         if (id != ISCSI_MAX_TARGET) {
 469                 if ((scan_data->channel == SCAN_WILD_CARD ||
 470                      scan_data->channel == 0) &&
 471                     (scan_data->id == SCAN_WILD_CARD ||
 472                      scan_data->id == id))
 473                         scsi_scan_target(&session->dev, 0, id,
 474                                          scan_data->lun, 1);
 475         }
 476         mutex_unlock(&ihost->mutex);
 477         return 0;
 478 }
 479
 480 static int iscsi_user_scan(struct Scsi_Host *shost, uint channel,
 481                            uint id, uint lun)
 482 {
 483         struct iscsi_scan_data scan_data;
 484
 485         scan_data.channel = channel;
 486         scan_data.id = id;
 487         scan_data.lun = lun;
 488
 489         return device_for_each_child(&shost->shost_gendev, &scan_data,
 490                                      iscsi_user_scan_session);
 491 }
 492
 493 static void iscsi_scan_session(struct work_struct *work)
 494 {
 495         struct iscsi_cls_session *session =
 496                         container_of(work, struct iscsi_cls_session, scan_work);
 497         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 498         struct iscsi_cls_host *ihost = shost->shost_data;
 499         struct iscsi_scan_data scan_data;
 500
 501         scan_data.channel = 0;
 502         scan_data.id = SCAN_WILD_CARD;
 503         scan_data.lun = SCAN_WILD_CARD;
 504
 505         iscsi_user_scan_session(&session->dev, &scan_data);
 506         atomic_dec(&ihost->nr_scans);
 507 }
 508
 509 static void session_recovery_timedout(struct work_struct *work)
 510 {
 511         struct iscsi_cls_session *session =
 512                 container_of(work, struct iscsi_cls_session,
 513                              recovery_work.work);
 514         unsigned long flags;
 515
 516         iscsi_cls_session_printk(KERN_INFO, session,
 517                                  "session recovery timed out after %d secs\n",
 518                                  session->recovery_tmo);
 519
 520         spin_lock_irqsave(&session->lock, flags);
 521         switch (session->state) {
 522         case ISCSI_SESSION_FAILED:
 523                 session->state = ISCSI_SESSION_FREE;
 524                 break;
 525         case ISCSI_SESSION_LOGGED_IN:
 526         case ISCSI_SESSION_FREE:
 527                 /* we raced with the unblock's flush */
 528                 spin_unlock_irqrestore(&session->lock, flags);
 529                 return;
 530         }
 531         spin_unlock_irqrestore(&session->lock, flags);
 532
 533         if (session->transport->session_recovery_timedout)
 534                 session->transport->session_recovery_timedout(session);
 535
 536         scsi_target_unblock(&session->dev);
 537 }
 538
 539 static void __iscsi_unblock_session(struct work_struct *work)
 540 {
 541         struct iscsi_cls_session *session =
 542                         container_of(work, struct iscsi_cls_session,
 543                                      unblock_work);
 544         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 545         struct iscsi_cls_host *ihost = shost->shost_data;
 546         unsigned long flags;
 547
 548         /*
 549          * The recovery and unblock work get run from the same workqueue,
 550          * so try to cancel it if it was going to run after this unblock.
 551          */
 552         cancel_delayed_work(&session->recovery_work);
 553         spin_lock_irqsave(&session->lock, flags);
 554         session->state = ISCSI_SESSION_LOGGED_IN;
 555         spin_unlock_irqrestore(&session->lock, flags);
 556         /* start IO */
 557         scsi_target_unblock(&session->dev);
 558         /*
 559          * Only do kernel scanning if the driver is properly hooked into
 560          * the async scanning code (drivers like iscsi_tcp do login and
 561          * scanning from userspace).
 562          */
 563         if (shost->hostt->scan_finished) {
 564                 if (queue_work(ihost->scan_workq, &session->scan_work))
 565                         atomic_inc(&ihost->nr_scans);
 566         }
 567 }
 568
 569 /**
 570  * iscsi_unblock_session - set a session as logged in and start IO.
 571  * @session: iscsi session
 572  *
 573  * Mark a session as ready to accept IO.
 574  */
 575 void iscsi_unblock_session(struct iscsi_cls_session *session)
 576 {
 577         queue_work(iscsi_eh_timer_workq, &session->unblock_work);
 578         /*
 579          * make sure all the events have completed before tell the driver
 580          * it is safe
 581          */
 582         flush_workqueue(iscsi_eh_timer_workq);
 583 }
 584 EXPORT_SYMBOL_GPL(iscsi_unblock_session);
 585
 586 static void __iscsi_block_session(struct work_struct *work)
 587 {
 588         struct iscsi_cls_session *session =
 589                         container_of(work, struct iscsi_cls_session,
 590                                      block_work);
 591         unsigned long flags;
 592
 593         spin_lock_irqsave(&session->lock, flags);
 594         session->state = ISCSI_SESSION_FAILED;
 595         spin_unlock_irqrestore(&session->lock, flags);
 596         scsi_target_block(&session->dev);
 597         queue_delayed_work(iscsi_eh_timer_workq, &session->recovery_work,
 598                            session->recovery_tmo * HZ);
 599 }
 600
 601 void iscsi_block_session(struct iscsi_cls_session *session)
 602 {
 603         queue_work(iscsi_eh_timer_workq, &session->block_work);
 604 }
 605 EXPORT_SYMBOL_GPL(iscsi_block_session);
 606
 607 static void __iscsi_unbind_session(struct work_struct *work)
 608 {
 609         struct iscsi_cls_session *session =
 610                         container_of(work, struct iscsi_cls_session,
 611                                      unbind_work);
 612         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 613         struct iscsi_cls_host *ihost = shost->shost_data;
 614         unsigned long flags;
 615
 616         /* Prevent new scans and make sure scanning is not in progress */
 617         mutex_lock(&ihost->mutex);
 618         spin_lock_irqsave(&session->lock, flags);
 619         if (session->target_id == ISCSI_MAX_TARGET) {
 620                 spin_unlock_irqrestore(&session->lock, flags);
 621                 mutex_unlock(&ihost->mutex);
 622                 return;
 623         }
 624         session->target_id = ISCSI_MAX_TARGET;
 625         spin_unlock_irqrestore(&session->lock, flags);
 626         mutex_unlock(&ihost->mutex);
 627
 628         scsi_remove_target(&session->dev);
 629         iscsi_session_event(session, ISCSI_KEVENT_UNBIND_SESSION);
 630 }
 631
 632 static int iscsi_unbind_session(struct iscsi_cls_session *session)
 633 {
 634         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 635         struct iscsi_cls_host *ihost = shost->shost_data;
 636
 637         return queue_work(ihost->scan_workq, &session->unbind_work);
 638 }
 639
 640 struct iscsi_cls_session *
 641 iscsi_alloc_session(struct Scsi_Host *shost, struct iscsi_transport *transport,
 642                     int dd_size)
 643 {
 644         struct iscsi_cls_session *session;
 645
 646         session = kzalloc(sizeof(*session) + dd_size,
 647                           GFP_KERNEL);
 648         if (!session)
 649                 return NULL;
 650
 651         session->transport = transport;
 652         session->recovery_tmo = 120;
 653         session->state = ISCSI_SESSION_FREE;
 654         INIT_DELAYED_WORK(&session->recovery_work, session_recovery_timedout);
 655         INIT_LIST_HEAD(&session->sess_list);
 656         INIT_WORK(&session->unblock_work, __iscsi_unblock_session);
 657         INIT_WORK(&session->block_work, __iscsi_block_session);
 658         INIT_WORK(&session->unbind_work, __iscsi_unbind_session);
 659         INIT_WORK(&session->scan_work, iscsi_scan_session);
 660         spin_lock_init(&session->lock);
 661
 662         /* this is released in the dev's release function */
 663         scsi_host_get(shost);
 664         session->dev.parent = &shost->shost_gendev;
 665         session->dev.release = iscsi_session_release;
 666         device_initialize(&session->dev);
 667         if (dd_size)
 668                 session->dd_data = &session[1];
 669         return session;
 670 }
 671 EXPORT_SYMBOL_GPL(iscsi_alloc_session);
 672
 673 static int iscsi_get_next_target_id(struct device *dev, void *data)
 674 {
 675         struct iscsi_cls_session *session;
 676         unsigned long flags;
 677         int err = 0;
 678
 679         if (!iscsi_is_session_dev(dev))
 680                 return 0;
 681
 682         session = iscsi_dev_to_session(dev);
 683         spin_lock_irqsave(&session->lock, flags);
 684         if (*((unsigned int *) data) == session->target_id)
 685                 err = -EEXIST;
 686         spin_unlock_irqrestore(&session->lock, flags);
 687         return err;
 688 }
 689
 690 int iscsi_add_session(struct iscsi_cls_session *session, unsigned int target_id)
 691 {
 692         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 693         struct iscsi_cls_host *ihost;
 694         unsigned long flags;
 695         unsigned int id = target_id;
 696         int err;
 697
 698         ihost = shost->shost_data;
 699         session->sid = atomic_add_return(1, &iscsi_session_nr);
 700
 701         if (id == ISCSI_MAX_TARGET) {
 702                 for (id = 0; id < ISCSI_MAX_TARGET; id++) {
 703                         err = device_for_each_child(&shost->shost_gendev, &id,
 704                                                     iscsi_get_next_target_id);
 705                         if (!err)
 706                                 break;
 707                 }
 708
 709                 if (id == ISCSI_MAX_TARGET) {
 710                         iscsi_cls_session_printk(KERN_ERR, session,
 711                                                  "Too many iscsi targets. Max "
 712                                                  "number of targets is %d.\n",
 713                                                  ISCSI_MAX_TARGET - 1);
 714                         goto release_host;
 715                 }
 716         }
 717         session->target_id = id;
 718
 719         snprintf(session->dev.bus_id, BUS_ID_SIZE, "session%u",
 720                  session->sid);
 721         err = device_add(&session->dev);
 722         if (err) {
 723                 iscsi_cls_session_printk(KERN_ERR, session,
 724                                          "could not register session's dev\n");
 725                 goto release_host;
 726         }
 727         transport_register_device(&session->dev);
 728
 729         spin_lock_irqsave(&sesslock, flags);
 730         list_add(&session->sess_list, &sesslist);
 731         spin_unlock_irqrestore(&sesslock, flags);
 732
 733         iscsi_session_event(session, ISCSI_KEVENT_CREATE_SESSION);
 734         return 0;
 735
 736 release_host:
 737         scsi_host_put(shost);
 738         return err;
 739 }
 740 EXPORT_SYMBOL_GPL(iscsi_add_session);
 741
 742 /**
 743  * iscsi_create_session - create iscsi class session
 744  * @shost: scsi host
 745  * @transport: iscsi transport
 746  * @dd_size: private driver data size
 747  * @target_id: which target
 748  *
 749  * This can be called from a LLD or iscsi_transport.
 750  */
 751 struct iscsi_cls_session *
 752 iscsi_create_session(struct Scsi_Host *shost, struct iscsi_transport *transport,
 753                      int dd_size, unsigned int target_id)
 754 {
 755         struct iscsi_cls_session *session;
 756
 757         session = iscsi_alloc_session(shost, transport, dd_size);
 758         if (!session)
 759                 return NULL;
 760
 761         if (iscsi_add_session(session, target_id)) {
 762                 iscsi_free_session(session);
 763                 return NULL;
 764         }
 765         return session;
 766 }
 767 EXPORT_SYMBOL_GPL(iscsi_create_session);
 768
 769 static void iscsi_conn_release(struct device *dev)
 770 {
 771         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev);
 772         struct device *parent = conn->dev.parent;
 773
 774         kfree(conn);
 775         put_device(parent);
 776 }
 777
 778 static int iscsi_is_conn_dev(const struct device *dev)
 779 {
 780         return dev->release == iscsi_conn_release;
 781 }
 782
 783 static int iscsi_iter_destroy_conn_fn(struct device *dev, void *data)
 784 {
 785         if (!iscsi_is_conn_dev(dev))
 786                 return 0;
 787         return iscsi_destroy_conn(iscsi_dev_to_conn(dev));
 788 }
 789
 790 void iscsi_remove_session(struct iscsi_cls_session *session)
 791 {
 792         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 793         struct iscsi_cls_host *ihost = shost->shost_data;
 794         unsigned long flags;
 795         int err;
 796
 797         spin_lock_irqsave(&sesslock, flags);
 798         list_del(&session->sess_list);
 799         spin_unlock_irqrestore(&sesslock, flags);
 800
 801         /* make sure there are no blocks/unblocks queued */
 802         flush_workqueue(iscsi_eh_timer_workq);
 803         /* make sure the timedout callout is not running */
 804         if (!cancel_delayed_work(&session->recovery_work))
 805                 flush_workqueue(iscsi_eh_timer_workq);
 806         /*
 807          * If we are blocked let commands flow again. The lld or iscsi
 808          * layer should set up the queuecommand to fail commands.
 809          * We assume that LLD will not be calling block/unblock while
 810          * removing the session.
 811          */
 812         spin_lock_irqsave(&session->lock, flags);
 813         session->state = ISCSI_SESSION_FREE;
 814         spin_unlock_irqrestore(&session->lock, flags);
 815
 816         scsi_target_unblock(&session->dev);
 817         /* flush running scans then delete devices */
 818         flush_workqueue(ihost->scan_workq);
 819         __iscsi_unbind_session(&session->unbind_work);
 820
 821         /* hw iscsi may not have removed all connections from session */
 822         err = device_for_each_child(&session->dev, NULL,
 823                                     iscsi_iter_destroy_conn_fn);
 824         if (err)
 825                 iscsi_cls_session_printk(KERN_ERR, session,
 826                                          "Could not delete all connections "
 827                                          "for session. Error %d.\n", err);
 828
 829         transport_unregister_device(&session->dev);
 830         device_del(&session->dev);
 831 }
 832 EXPORT_SYMBOL_GPL(iscsi_remove_session);
 833
 834 void iscsi_free_session(struct iscsi_cls_session *session)
 835 {
 836         iscsi_session_event(session, ISCSI_KEVENT_DESTROY_SESSION);
 837         put_device(&session->dev);
 838 }
 839 EXPORT_SYMBOL_GPL(iscsi_free_session);
 840
 841 /**
 842  * iscsi_destroy_session - destroy iscsi session
 843  * @session: iscsi_session
 844  *
 845  * Can be called by a LLD or iscsi_transport. There must not be
 846  * any running connections.
 847  */
 848 int iscsi_destroy_session(struct iscsi_cls_session *session)
 849 {
 850         iscsi_remove_session(session);
 851         iscsi_free_session(session);
 852         return 0;
 853 }
 854 EXPORT_SYMBOL_GPL(iscsi_destroy_session);
 855
 856 /**
 857  * iscsi_create_conn - create iscsi class connection
 858  * @session: iscsi cls session
 859  * @dd_size: private driver data size
 860  * @cid: connection id
 861  *
 862  * This can be called from a LLD or iscsi_transport. The connection
 863  * is child of the session so cid must be unique for all connections
 864  * on the session.
 865  *
 866  * Since we do not support MCS, cid will normally be zero. In some cases
 867  * for software iscsi we could be trying to preallocate a connection struct
 868  * in which case there could be two connection structs and cid would be
 869  * non-zero.
 870  */
 871 struct iscsi_cls_conn *
 872 iscsi_create_conn(struct iscsi_cls_session *session, int dd_size, uint32_t cid)
 873 {
 874         struct iscsi_transport *transport = session->transport;
 875         struct iscsi_cls_conn *conn;
 876         unsigned long flags;
 877         int err;
 878
 879         conn = kzalloc(sizeof(*conn) + dd_size, GFP_KERNEL);
 880         if (!conn)
 881                 return NULL;
 882         if (dd_size)
 883                 conn->dd_data = &conn[1];
 884
 885         INIT_LIST_HEAD(&conn->conn_list);
 886         conn->transport = transport;
 887         conn->cid = cid;
 888
 889         /* this is released in the dev's release function */
 890         if (!get_device(&session->dev))
 891                 goto free_conn;
 892
 893         snprintf(conn->dev.bus_id, BUS_ID_SIZE, "connection%d:%u",
 894                  session->sid, cid);
 895         conn->dev.parent = &session->dev;
 896         conn->dev.release = iscsi_conn_release;
 897         err = device_register(&conn->dev);
 898         if (err) {
 899                 iscsi_cls_session_printk(KERN_ERR, session, "could not "
 900                                          "register connection's dev\n");
 901                 goto release_parent_ref;
 902         }
 903         transport_register_device(&conn->dev);
 904
 905         spin_lock_irqsave(&connlock, flags);
 906         list_add(&conn->conn_list, &connlist);
 907         conn->active = 1;
 908         spin_unlock_irqrestore(&connlock, flags);
 909         return conn;
 910
 911 release_parent_ref:
 912         put_device(&session->dev);
 913 free_conn:
 914         kfree(conn);
 915         return NULL;
 916 }
 917
 918 EXPORT_SYMBOL_GPL(iscsi_create_conn);
 919
 920 /**
 921  * iscsi_destroy_conn - destroy iscsi class connection
 922  * @conn: iscsi cls session
 923  *
 924  * This can be called from a LLD or iscsi_transport.
 925  */
 926 int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
 927 {
 928         unsigned long flags;
 929
 930         spin_lock_irqsave(&connlock, flags);
 931         conn->active = 0;
 932         list_del(&conn->conn_list);
 933         spin_unlock_irqrestore(&connlock, flags);
 934
 935         transport_unregister_device(&conn->dev);
 936         device_unregister(&conn->dev);
 937         return 0;
 938 }
 939 EXPORT_SYMBOL_GPL(iscsi_destroy_conn);
 940
 941 /*
 942  * iscsi interface functions
 943  */
 944 static struct iscsi_internal *
 945 iscsi_if_transport_lookup(struct iscsi_transport *tt)
 946 {
 947         struct iscsi_internal *priv;
 948         unsigned long flags;
 949
 950         spin_lock_irqsave(&iscsi_transport_lock, flags);
 951         list_for_each_entry(priv, &iscsi_transports, list) {
 952                 if (tt == priv->iscsi_transport) {
 953                         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 954                         return priv;
 955                 }
 956         }
 957         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 958         return NULL;
 959 }
 960
 961 static int
 962 iscsi_broadcast_skb(struct sk_buff *skb, gfp_t gfp)
 963 {
 964         int rc;
 965
 966         rc = netlink_broadcast(nls, skb, 0, 1, gfp);
 967         if (rc < 0) {
 968                 printk(KERN_ERR "iscsi: can not broadcast skb (%d)\n", rc);
 969                 return rc;
 970         }
 971
 972         return 0;
 973 }
 974
 975 static int
 976 iscsi_unicast_skb(struct sk_buff *skb, int pid)
 977 {
 978         int rc;
 979
 980         rc = netlink_unicast(nls, skb, pid, MSG_DONTWAIT);
 981         if (rc < 0) {
 982                 printk(KERN_ERR "iscsi: can not unicast skb (%d)\n", rc);
 983                 return rc;
 984         }
 985
 986         return 0;
 987 }
 988
 989 int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
 990                    char *data, uint32_t data_size)
 991 {
 992         struct nlmsghdr *nlh;
 993         struct sk_buff *skb;
 994         struct iscsi_uevent *ev;
 995         char *pdu;
 996         struct iscsi_internal *priv;
 997         int len = NLMSG_SPACE(sizeof(*ev) + sizeof(struct iscsi_hdr) +
 998                               data_size);
 999
1000         priv = iscsi_if_transport_lookup(conn->transport);
1001         if (!priv)
1002                 return -EINVAL;
1003
1004         skb = alloc_skb(len, GFP_ATOMIC);
1005         if (!skb) {
1006                 iscsi_conn_error(conn, ISCSI_ERR_CONN_FAILED);
1007                 iscsi_cls_conn_printk(KERN_ERR, conn, "can not deliver "
1008                                       "control PDU: OOM\n");
1009                 return -ENOMEM;
1010         }
1011
1012         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
1013         ev = NLMSG_DATA(nlh);
1014         memset(ev, 0, sizeof(*ev));
1015         ev->transport_handle = iscsi_handle(conn->transport);
1016         ev->type = ISCSI_KEVENT_RECV_PDU;
1017         ev->r.recv_req.cid = conn->cid;
1018         ev->r.recv_req.sid = iscsi_conn_get_sid(conn);
1019         pdu = (char*)ev + sizeof(*ev);
1020         memcpy(pdu, hdr, sizeof(struct iscsi_hdr));
1021         memcpy(pdu + sizeof(struct iscsi_hdr), data, data_size);
1022
1023         return iscsi_unicast_skb(skb, priv->daemon_pid);
1024 }
1025 EXPORT_SYMBOL_GPL(iscsi_recv_pdu);
1026
1027 void iscsi_conn_error(struct iscsi_cls_conn *conn, enum iscsi_err error)
1028 {
1029         struct nlmsghdr *nlh;
1030         struct sk_buff  *skb;
1031         struct iscsi_uevent *ev;
1032         struct iscsi_internal *priv;
1033         int len = NLMSG_SPACE(sizeof(*ev));
1034
1035         priv = iscsi_if_transport_lookup(conn->transport);
1036         if (!priv)
1037                 return;
1038
1039         skb = alloc_skb(len, GFP_ATOMIC);
1040         if (!skb) {
1041                 iscsi_cls_conn_printk(KERN_ERR, conn, "gracefully ignored "
1042                                       "conn error (%d)\n", error);
1043                 return;
1044         }
1045
1046         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
1047         ev = NLMSG_DATA(nlh);
1048         ev->transport_handle = iscsi_handle(conn->transport);
1049         ev->type = ISCSI_KEVENT_CONN_ERROR;
1050         ev->r.connerror.error = error;
1051         ev->r.connerror.cid = conn->cid;
1052         ev->r.connerror.sid = iscsi_conn_get_sid(conn);
1053
1054         iscsi_broadcast_skb(skb, GFP_ATOMIC);
1055
1056         iscsi_cls_conn_printk(KERN_INFO, conn, "detected conn error (%d)\n",
1057                               error);
1058 }
1059 EXPORT_SYMBOL_GPL(iscsi_conn_error);
1060
1061 static int
1062 iscsi_if_send_reply(int pid, int seq, int type, int done, int multi,
1063                       void *payload, int size)
1064 {
1065         struct sk_buff  *skb;
1066         struct nlmsghdr *nlh;
1067         int len = NLMSG_SPACE(size);
1068         int flags = multi ? NLM_F_MULTI : 0;
1069         int t = done ? NLMSG_DONE : type;
1070
1071         skb = alloc_skb(len, GFP_ATOMIC);
1072         if (!skb) {
1073                 printk(KERN_ERR "Could not allocate skb to send reply.\n");
1074                 return -ENOMEM;
1075         }
1076
1077         nlh = __nlmsg_put(skb, pid, seq, t, (len - sizeof(*nlh)), 0);
1078         nlh->nlmsg_flags = flags;
1079         memcpy(NLMSG_DATA(nlh), payload, size);
1080         return iscsi_unicast_skb(skb, pid);
1081 }
1082
1083 static int
1084 iscsi_if_get_stats(struct iscsi_transport *transport, struct nlmsghdr *nlh)
1085 {
1086         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1087         struct iscsi_stats *stats;
1088         struct sk_buff *skbstat;
1089         struct iscsi_cls_conn *conn;
1090         struct nlmsghdr *nlhstat;
1091         struct iscsi_uevent *evstat;
1092         struct iscsi_internal *priv;
1093         int len = NLMSG_SPACE(sizeof(*ev) +
1094                               sizeof(struct iscsi_stats) +
1095                               sizeof(struct iscsi_stats_custom) *
1096                               ISCSI_STATS_CUSTOM_MAX);
1097         int err = 0;
1098
1099         priv = iscsi_if_transport_lookup(transport);
1100         if (!priv)
1101                 return -EINVAL;
1102
1103         conn = iscsi_conn_lookup(ev->u.get_stats.sid, ev->u.get_stats.cid);
1104         if (!conn)
1105                 return -EEXIST;
1106
1107         do {
1108                 int actual_size;
1109
1110                 skbstat = alloc_skb(len, GFP_ATOMIC);
1111                 if (!skbstat) {
1112                         iscsi_cls_conn_printk(KERN_ERR, conn, "can not "
1113                                               "deliver stats: OOM\n");
1114                         return -ENOMEM;
1115                 }
1116
1117                 nlhstat = __nlmsg_put(skbstat, priv->daemon_pid, 0, 0,
1118                                       (len - sizeof(*nlhstat)), 0);
1119                 evstat = NLMSG_DATA(nlhstat);
1120                 memset(evstat, 0, sizeof(*evstat));
1121                 evstat->transport_handle = iscsi_handle(conn->transport);
1122                 evstat->type = nlh->nlmsg_type;
1123                 evstat->u.get_stats.cid =
1124                         ev->u.get_stats.cid;
1125                 evstat->u.get_stats.sid =
1126                         ev->u.get_stats.sid;
1127                 stats = (struct iscsi_stats *)
1128                         ((char*)evstat + sizeof(*evstat));
1129                 memset(stats, 0, sizeof(*stats));
1130
1131                 transport->get_stats(conn, stats);
1132                 actual_size = NLMSG_SPACE(sizeof(struct iscsi_uevent) +
1133                                           sizeof(struct iscsi_stats) +
1134                                           sizeof(struct iscsi_stats_custom) *
1135                                           stats->custom_length);
1136                 actual_size -= sizeof(*nlhstat);
1137                 actual_size = NLMSG_LENGTH(actual_size);
1138                 skb_trim(skbstat, NLMSG_ALIGN(actual_size));
1139                 nlhstat->nlmsg_len = actual_size;
1140
1141                 err = iscsi_unicast_skb(skbstat, priv->daemon_pid);
1142         } while (err < 0 && err != -ECONNREFUSED);
1143
1144         return err;
1145 }
1146
1147 /**
1148  * iscsi_session_event - send session destr. completion event
1149  * @session: iscsi class session
1150  * @event: type of event
1151  */
1152 int iscsi_session_event(struct iscsi_cls_session *session,
1153                         enum iscsi_uevent_e event)
1154 {
1155         struct iscsi_internal *priv;
1156         struct Scsi_Host *shost;
1157         struct iscsi_uevent *ev;
1158         struct sk_buff  *skb;
1159         struct nlmsghdr *nlh;
1160         int rc, len = NLMSG_SPACE(sizeof(*ev));
1161
1162         priv = iscsi_if_transport_lookup(session->transport);
1163         if (!priv)
1164                 return -EINVAL;
1165         shost = iscsi_session_to_shost(session);
1166
1167         skb = alloc_skb(len, GFP_KERNEL);
1168         if (!skb) {
1169                 iscsi_cls_session_printk(KERN_ERR, session,
1170                                          "Cannot notify userspace of session "
1171                                          "event %u\n", event);
1172                 return -ENOMEM;
1173         }
1174
1175         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
1176         ev = NLMSG_DATA(nlh);
1177         ev->transport_handle = iscsi_handle(session->transport);
1178
1179         ev->type = event;
1180         switch (event) {
1181         case ISCSI_KEVENT_DESTROY_SESSION:
1182                 ev->r.d_session.host_no = shost->host_no;
1183                 ev->r.d_session.sid = session->sid;
1184                 break;
1185         case ISCSI_KEVENT_CREATE_SESSION:
1186                 ev->r.c_session_ret.host_no = shost->host_no;
1187                 ev->r.c_session_ret.sid = session->sid;
1188                 break;
1189         case ISCSI_KEVENT_UNBIND_SESSION:
1190                 ev->r.unbind_session.host_no = shost->host_no;
1191                 ev->r.unbind_session.sid = session->sid;
1192                 break;
1193         default:
1194                 iscsi_cls_session_printk(KERN_ERR, session, "Invalid event "
1195                                          "%u.\n", event);
1196                 kfree_skb(skb);
1197                 return -EINVAL;
1198         }
1199
1200         /*
1201          * this will occur if the daemon is not up, so we just warn
1202          * the user and when the daemon is restarted it will handle it
1203          */
1204         rc = iscsi_broadcast_skb(skb, GFP_KERNEL);
1205         if (rc < 0)
1206                 iscsi_cls_session_printk(KERN_ERR, session,
1207                                          "Cannot notify userspace of session "
1208                                          "event %u. Check iscsi daemon\n",
1209                                          event);
1210         return rc;
1211 }
1212 EXPORT_SYMBOL_GPL(iscsi_session_event);
1213
1214 static int
1215 iscsi_if_create_session(struct iscsi_internal *priv, struct iscsi_endpoint *ep,
1216                         struct iscsi_uevent *ev, uint32_t initial_cmdsn,
1217                         uint16_t cmds_max, uint16_t queue_depth)
1218 {
1219         struct iscsi_transport *transport = priv->iscsi_transport;
1220         struct iscsi_cls_session *session;
1221         uint32_t host_no;
1222
1223         session = transport->create_session(ep, cmds_max, queue_depth,
1224                                             initial_cmdsn, &host_no);
1225         if (!session)
1226                 return -ENOMEM;
1227
1228         ev->r.c_session_ret.host_no = host_no;
1229         ev->r.c_session_ret.sid = session->sid;
1230         return 0;
1231 }
1232
1233 static int
1234 iscsi_if_create_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1235 {
1236         struct iscsi_cls_conn *conn;
1237         struct iscsi_cls_session *session;
1238
1239         session = iscsi_session_lookup(ev->u.c_conn.sid);
1240         if (!session) {
1241                 printk(KERN_ERR "iscsi: invalid session %d.\n",
1242                        ev->u.c_conn.sid);
1243                 return -EINVAL;
1244         }
1245
1246         conn = transport->create_conn(session, ev->u.c_conn.cid);
1247         if (!conn) {
1248                 iscsi_cls_session_printk(KERN_ERR, session,
1249                                          "couldn't create a new connection.");
1250                 return -ENOMEM;
1251         }
1252
1253         ev->r.c_conn_ret.sid = session->sid;
1254         ev->r.c_conn_ret.cid = conn->cid;
1255         return 0;
1256 }
1257
1258 static int
1259 iscsi_if_destroy_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1260 {
1261         struct iscsi_cls_conn *conn;
1262
1263         conn = iscsi_conn_lookup(ev->u.d_conn.sid, ev->u.d_conn.cid);
1264         if (!conn)
1265                 return -EINVAL;
1266
1267         if (transport->destroy_conn)
1268                 transport->destroy_conn(conn);
1269         return 0;
1270 }
1271
1272 static int
1273 iscsi_set_param(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1274 {
1275         char *data = (char*)ev + sizeof(*ev);
1276         struct iscsi_cls_conn *conn;
1277         struct iscsi_cls_session *session;
1278         int err = 0, value = 0;
1279
1280         session = iscsi_session_lookup(ev->u.set_param.sid);
1281         conn = iscsi_conn_lookup(ev->u.set_param.sid, ev->u.set_param.cid);
1282         if (!conn || !session)
1283                 return -EINVAL;
1284
1285         switch (ev->u.set_param.param) {
1286         case ISCSI_PARAM_SESS_RECOVERY_TMO:
1287                 sscanf(data, "%d", &value);
1288                 if (value != 0)
1289                         session->recovery_tmo = value;
1290                 break;
1291         default:
1292                 err = transport->set_param(conn, ev->u.set_param.param,
1293                                            data, ev->u.set_param.len);
1294         }
1295
1296         return err;
1297 }
1298
1299 static int
1300 iscsi_if_transport_ep(struct iscsi_transport *transport,
1301                       struct iscsi_uevent *ev, int msg_type)
1302 {
1303         struct iscsi_endpoint *ep;
1304         struct sockaddr *dst_addr;
1305         int rc = 0;
1306
1307         switch (msg_type) {
1308         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1309                 if (!transport->ep_connect)
1310                         return -EINVAL;
1311
1312                 dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1313                 ep = transport->ep_connect(dst_addr,
1314                                            ev->u.ep_connect.non_blocking);
1315                 if (IS_ERR(ep))
1316                         return PTR_ERR(ep);
1317
1318                 ev->r.ep_connect_ret.handle = ep->id;
1319                 break;
1320         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1321                 if (!transport->ep_poll)
1322                         return -EINVAL;
1323
1324                 ep = iscsi_lookup_endpoint(ev->u.ep_poll.ep_handle);
1325                 if (!ep)
1326                         return -EINVAL;
1327
1328                 ev->r.retcode = transport->ep_poll(ep,
1329                                                    ev->u.ep_poll.timeout_ms);
1330                 break;
1331         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1332                 if (!transport->ep_disconnect)
1333                         return -EINVAL;
1334
1335                 ep = iscsi_lookup_endpoint(ev->u.ep_disconnect.ep_handle);
1336                 if (!ep)
1337                         return -EINVAL;
1338
1339                 transport->ep_disconnect(ep);
1340                 break;
1341         }
1342         return rc;
1343 }
1344
1345 static int
1346 iscsi_tgt_dscvr(struct iscsi_transport *transport,
1347                 struct iscsi_uevent *ev)
1348 {
1349         struct Scsi_Host *shost;
1350         struct sockaddr *dst_addr;
1351         int err;
1352
1353         if (!transport->tgt_dscvr)
1354                 return -EINVAL;
1355
1356         shost = scsi_host_lookup(ev->u.tgt_dscvr.host_no);
1357         if (IS_ERR(shost)) {
1358                 printk(KERN_ERR "target discovery could not find host no %u\n",
1359                        ev->u.tgt_dscvr.host_no);
1360                 return -ENODEV;
1361         }
1362
1363
1364         dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1365         err = transport->tgt_dscvr(shost, ev->u.tgt_dscvr.type,
1366                                    ev->u.tgt_dscvr.enable, dst_addr);
1367         scsi_host_put(shost);
1368         return err;
1369 }
1370
1371 static int
1372 iscsi_set_host_param(struct iscsi_transport *transport,
1373                      struct iscsi_uevent *ev)
1374 {
1375         char *data = (char*)ev + sizeof(*ev);
1376         struct Scsi_Host *shost;
1377         int err;
1378
1379         if (!transport->set_host_param)
1380                 return -ENOSYS;
1381
1382         shost = scsi_host_lookup(ev->u.set_host_param.host_no);
1383         if (IS_ERR(shost)) {
1384                 printk(KERN_ERR "set_host_param could not find host no %u\n",
1385                        ev->u.set_host_param.host_no);
1386                 return -ENODEV;
1387         }
1388
1389         err = transport->set_host_param(shost, ev->u.set_host_param.param,
1390                                         data, ev->u.set_host_param.len);
1391         scsi_host_put(shost);
1392         return err;
1393 }
1394
1395 static int
1396 iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
1397 {
1398         int err = 0;
1399         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1400         struct iscsi_transport *transport = NULL;
1401         struct iscsi_internal *priv;
1402         struct iscsi_cls_session *session;
1403         struct iscsi_cls_conn *conn;
1404         struct iscsi_endpoint *ep = NULL;
1405
1406         priv = iscsi_if_transport_lookup(iscsi_ptr(ev->transport_handle));
1407         if (!priv)
1408                 return -EINVAL;
1409         transport = priv->iscsi_transport;
1410
1411         if (!try_module_get(transport->owner))
1412                 return -EINVAL;
1413
1414         priv->daemon_pid = NETLINK_CREDS(skb)->pid;
1415
1416         switch (nlh->nlmsg_type) {
1417         case ISCSI_UEVENT_CREATE_SESSION:
1418                 err = iscsi_if_create_session(priv, ep, ev,
1419                                               ev->u.c_session.initial_cmdsn,
1420                                               ev->u.c_session.cmds_max,
1421                                               ev->u.c_session.queue_depth);
1422                 break;
1423         case ISCSI_UEVENT_CREATE_BOUND_SESSION:
1424                 ep = iscsi_lookup_endpoint(ev->u.c_bound_session.ep_handle);
1425                 if (!ep) {
1426                         err = -EINVAL;
1427                         break;
1428                 }
1429
1430                 err = iscsi_if_create_session(priv, ep, ev,
1431                                         ev->u.c_bound_session.initial_cmdsn,
1432                                         ev->u.c_bound_session.cmds_max,
1433                                         ev->u.c_bound_session.queue_depth);
1434                 break;
1435         case ISCSI_UEVENT_DESTROY_SESSION:
1436                 session = iscsi_session_lookup(ev->u.d_session.sid);
1437                 if (session)
1438                         transport->destroy_session(session);
1439                 else
1440                         err = -EINVAL;
1441                 break;
1442         case ISCSI_UEVENT_UNBIND_SESSION:
1443                 session = iscsi_session_lookup(ev->u.d_session.sid);
1444                 if (session)
1445                         iscsi_unbind_session(session);
1446                 else
1447                         err = -EINVAL;
1448                 break;
1449         case ISCSI_UEVENT_CREATE_CONN:
1450                 err = iscsi_if_create_conn(transport, ev);
1451                 break;
1452         case ISCSI_UEVENT_DESTROY_CONN:
1453                 err = iscsi_if_destroy_conn(transport, ev);
1454                 break;
1455         case ISCSI_UEVENT_BIND_CONN:
1456                 session = iscsi_session_lookup(ev->u.b_conn.sid);
1457                 conn = iscsi_conn_lookup(ev->u.b_conn.sid, ev->u.b_conn.cid);
1458
1459                 if (session && conn)
1460                         ev->r.retcode = transport->bind_conn(session, conn,
1461                                         ev->u.b_conn.transport_eph,
1462                                         ev->u.b_conn.is_leading);
1463                 else
1464                         err = -EINVAL;
1465                 break;
1466         case ISCSI_UEVENT_SET_PARAM:
1467                 err = iscsi_set_param(transport, ev);
1468                 break;
1469         case ISCSI_UEVENT_START_CONN:
1470                 conn = iscsi_conn_lookup(ev->u.start_conn.sid, ev->u.start_conn.cid);
1471                 if (conn)
1472                         ev->r.retcode = transport->start_conn(conn);
1473                 else
1474                         err = -EINVAL;
1475                 break;
1476         case ISCSI_UEVENT_STOP_CONN:
1477                 conn = iscsi_conn_lookup(ev->u.stop_conn.sid, ev->u.stop_conn.cid);
1478                 if (conn)
1479                         transport->stop_conn(conn, ev->u.stop_conn.flag);
1480                 else
1481                         err = -EINVAL;
1482                 break;
1483         case ISCSI_UEVENT_SEND_PDU:
1484                 conn = iscsi_conn_lookup(ev->u.send_pdu.sid, ev->u.send_pdu.cid);
1485                 if (conn)
1486                         ev->r.retcode = transport->send_pdu(conn,
1487                                 (struct iscsi_hdr*)((char*)ev + sizeof(*ev)),
1488                                 (char*)ev + sizeof(*ev) + ev->u.send_pdu.hdr_size,
1489                                 ev->u.send_pdu.data_size);
1490                 else
1491                         err = -EINVAL;
1492                 break;
1493         case ISCSI_UEVENT_GET_STATS:
1494                 err = iscsi_if_get_stats(transport, nlh);
1495                 break;
1496         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1497         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1498         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1499                 err = iscsi_if_transport_ep(transport, ev, nlh->nlmsg_type);
1500                 break;
1501         case ISCSI_UEVENT_TGT_DSCVR:
1502                 err = iscsi_tgt_dscvr(transport, ev);
1503                 break;
1504         case ISCSI_UEVENT_SET_HOST_PARAM:
1505                 err = iscsi_set_host_param(transport, ev);
1506                 break;
1507         default:
1508                 err = -ENOSYS;
1509                 break;
1510         }
1511
1512         module_put(transport->owner);
1513         return err;
1514 }
1515
1516 /*
1517  * Get message from skb.  Each message is processed by iscsi_if_recv_msg.
1518  * Malformed skbs with wrong lengths or invalid creds are not processed.
1519  */
1520 static void
1521 iscsi_if_rx(struct sk_buff *skb)
1522 {
1523         mutex_lock(&rx_queue_mutex);
1524         while (skb->len >= NLMSG_SPACE(0)) {
1525                 int err;
1526                 uint32_t rlen;
1527                 struct nlmsghdr *nlh;
1528                 struct iscsi_uevent *ev;
1529
1530                 nlh = nlmsg_hdr(skb);
1531                 if (nlh->nlmsg_len < sizeof(*nlh) ||
1532                     skb->len < nlh->nlmsg_len) {
1533                         break;
1534                 }
1535
1536                 ev = NLMSG_DATA(nlh);
1537                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1538                 if (rlen > skb->len)
1539                         rlen = skb->len;
1540
1541                 err = iscsi_if_recv_msg(skb, nlh);
1542                 if (err) {
1543                         ev->type = ISCSI_KEVENT_IF_ERROR;
1544                         ev->iferror = err;
1545                 }
1546                 do {
1547                         /*
1548                          * special case for GET_STATS:
1549                          * on success - sending reply and stats from
1550                          * inside of if_recv_msg(),
1551                          * on error - fall through.
1552                          */
1553                         if (ev->type == ISCSI_UEVENT_GET_STATS && !err)
1554                                 break;
1555                         err = iscsi_if_send_reply(
1556                                 NETLINK_CREDS(skb)->pid, nlh->nlmsg_seq,
1557                                 nlh->nlmsg_type, 0, 0, ev, sizeof(*ev));
1558                 } while (err < 0 && err != -ECONNREFUSED);
1559                 skb_pull(skb, rlen);
1560         }
1561         mutex_unlock(&rx_queue_mutex);
1562 }
1563
1564 #define ISCSI_CLASS_ATTR(_prefix,_name,_mode,_show,_store)              \
1565 struct device_attribute dev_attr_##_prefix##_##_name =  \
1566         __ATTR(_name,_mode,_show,_store)
1567
1568 /*
1569  * iSCSI connection attrs
1570  */
1571 #define iscsi_conn_attr_show(param)                                     \
1572 static ssize_t                                                          \
1573 show_conn_param_##param(struct device *dev,                             \
1574                         struct device_attribute *attr, char *buf)       \
1575 {                                                                       \
1576         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev->parent);   \
1577         struct iscsi_transport *t = conn->transport;                    \
1578         return t->get_conn_param(conn, param, buf);                     \
1579 }
1580
1581 #define iscsi_conn_attr(field, param)                                   \
1582         iscsi_conn_attr_show(param)                                     \
1583 static ISCSI_CLASS_ATTR(conn, field, S_IRUGO, show_conn_param_##param,  \
1584                         NULL);
1585
1586 iscsi_conn_attr(max_recv_dlength, ISCSI_PARAM_MAX_RECV_DLENGTH);
1587 iscsi_conn_attr(max_xmit_dlength, ISCSI_PARAM_MAX_XMIT_DLENGTH);
1588 iscsi_conn_attr(header_digest, ISCSI_PARAM_HDRDGST_EN);
1589 iscsi_conn_attr(data_digest, ISCSI_PARAM_DATADGST_EN);
1590 iscsi_conn_attr(ifmarker, ISCSI_PARAM_IFMARKER_EN);
1591 iscsi_conn_attr(ofmarker, ISCSI_PARAM_OFMARKER_EN);
1592 iscsi_conn_attr(persistent_port, ISCSI_PARAM_PERSISTENT_PORT);
1593 iscsi_conn_attr(port, ISCSI_PARAM_CONN_PORT);
1594 iscsi_conn_attr(exp_statsn, ISCSI_PARAM_EXP_STATSN);
1595 iscsi_conn_attr(persistent_address, ISCSI_PARAM_PERSISTENT_ADDRESS);
1596 iscsi_conn_attr(address, ISCSI_PARAM_CONN_ADDRESS);
1597 iscsi_conn_attr(ping_tmo, ISCSI_PARAM_PING_TMO);
1598 iscsi_conn_attr(recv_tmo, ISCSI_PARAM_RECV_TMO);
1599
1600 /*
1601  * iSCSI session attrs
1602  */
1603 #define iscsi_session_attr_show(param, perm)                            \
1604 static ssize_t                                                          \
1605 show_session_param_##param(struct device *dev,                          \
1606                            struct device_attribute *attr, char *buf)    \
1607 {                                                                       \
1608         struct iscsi_cls_session *session =                             \
1609                 iscsi_dev_to_session(dev->parent);                      \
1610         struct iscsi_transport *t = session->transport;                 \
1611                                                                         \
1612         if (perm && !capable(CAP_SYS_ADMIN))                            \
1613                 return -EACCES;                                         \
1614         return t->get_session_param(session, param, buf);               \
1615 }
1616
1617 #define iscsi_session_attr(field, param, perm)                          \
1618         iscsi_session_attr_show(param, perm)                            \
1619 static ISCSI_CLASS_ATTR(sess, field, S_IRUGO, show_session_param_##param, \
1620                         NULL);
1621
1622 iscsi_session_attr(targetname, ISCSI_PARAM_TARGET_NAME, 0);
1623 iscsi_session_attr(initial_r2t, ISCSI_PARAM_INITIAL_R2T_EN, 0);
1624 iscsi_session_attr(max_outstanding_r2t, ISCSI_PARAM_MAX_R2T, 0);
1625 iscsi_session_attr(immediate_data, ISCSI_PARAM_IMM_DATA_EN, 0);
1626 iscsi_session_attr(first_burst_len, ISCSI_PARAM_FIRST_BURST, 0);
1627 iscsi_session_attr(max_burst_len, ISCSI_PARAM_MAX_BURST, 0);
1628 iscsi_session_attr(data_pdu_in_order, ISCSI_PARAM_PDU_INORDER_EN, 0);
1629 iscsi_session_attr(data_seq_in_order, ISCSI_PARAM_DATASEQ_INORDER_EN, 0);
1630 iscsi_session_attr(erl, ISCSI_PARAM_ERL, 0);
1631 iscsi_session_attr(tpgt, ISCSI_PARAM_TPGT, 0);
1632 iscsi_session_attr(username, ISCSI_PARAM_USERNAME, 1);
1633 iscsi_session_attr(username_in, ISCSI_PARAM_USERNAME_IN, 1);
1634 iscsi_session_attr(password, ISCSI_PARAM_PASSWORD, 1);
1635 iscsi_session_attr(password_in, ISCSI_PARAM_PASSWORD_IN, 1);
1636 iscsi_session_attr(fast_abort, ISCSI_PARAM_FAST_ABORT, 0);
1637 iscsi_session_attr(abort_tmo, ISCSI_PARAM_ABORT_TMO, 0);
1638 iscsi_session_attr(lu_reset_tmo, ISCSI_PARAM_LU_RESET_TMO, 0);
1639 iscsi_session_attr(ifacename, ISCSI_PARAM_IFACE_NAME, 0);
1640 iscsi_session_attr(initiatorname, ISCSI_PARAM_INITIATOR_NAME, 0)
1641
1642 static ssize_t
1643 show_priv_session_state(struct device *dev, struct device_attribute *attr,
1644                         char *buf)
1645 {
1646         struct iscsi_cls_session *session = iscsi_dev_to_session(dev->parent);
1647         return sprintf(buf, "%s\n", iscsi_session_state_name(session->state));
1648 }
1649 static ISCSI_CLASS_ATTR(priv_sess, state, S_IRUGO, show_priv_session_state,
1650                         NULL);
1651
1652 #define iscsi_priv_session_attr_show(field, format)                     \
1653 static ssize_t                                                          \
1654 show_priv_session_##field(struct device *dev,                           \
1655                           struct device_attribute *attr, char *buf)     \
1656 {                                                                       \
1657         struct iscsi_cls_session *session =                             \
1658                         iscsi_dev_to_session(dev->parent);              \
1659         return sprintf(buf, format"\n", session->field);                \
1660 }
1661
1662 #define iscsi_priv_session_attr(field, format)                          \
1663         iscsi_priv_session_attr_show(field, format)                     \
1664 static ISCSI_CLASS_ATTR(priv_sess, field, S_IRUGO, show_priv_session_##field, \
1665                         NULL)
1666 iscsi_priv_session_attr(recovery_tmo, "%d");
1667
1668 /*
1669  * iSCSI host attrs
1670  */
1671 #define iscsi_host_attr_show(param)                                     \
1672 static ssize_t                                                          \
1673 show_host_param_##param(struct device *dev,                             \
1674                         struct device_attribute *attr, char *buf)       \
1675 {                                                                       \
1676         struct Scsi_Host *shost = transport_class_to_shost(dev);        \
1677         struct iscsi_internal *priv = to_iscsi_internal(shost->transportt); \
1678         return priv->iscsi_transport->get_host_param(shost, param, buf); \
1679 }
1680
1681 #define iscsi_host_attr(field, param)                                   \
1682         iscsi_host_attr_show(param)                                     \
1683 static ISCSI_CLASS_ATTR(host, field, S_IRUGO, show_host_param_##param,  \
1684                         NULL);
1685
1686 iscsi_host_attr(netdev, ISCSI_HOST_PARAM_NETDEV_NAME);
1687 iscsi_host_attr(hwaddress, ISCSI_HOST_PARAM_HWADDRESS);
1688 iscsi_host_attr(ipaddress, ISCSI_HOST_PARAM_IPADDRESS);
1689 iscsi_host_attr(initiatorname, ISCSI_HOST_PARAM_INITIATOR_NAME);
1690
1691 #define SETUP_PRIV_SESSION_RD_ATTR(field)                               \
1692 do {                                                                    \
1693         priv->session_attrs[count] = &dev_attr_priv_sess_##field; \
1694         count++;                                                        \
1695 } while (0)
1696
1697
1698 #define SETUP_SESSION_RD_ATTR(field, param_flag)                        \
1699 do {                                                                    \
1700         if (tt->param_mask & param_flag) {                              \
1701                 priv->session_attrs[count] = &dev_attr_sess_##field; \
1702                 count++;                                                \
1703         }                                                               \
1704 } while (0)
1705
1706 #define SETUP_CONN_RD_ATTR(field, param_flag)                           \
1707 do {                                                                    \
1708         if (tt->param_mask & param_flag) {                              \
1709                 priv->conn_attrs[count] = &dev_attr_conn_##field; \
1710                 count++;                                                \
1711         }                                                               \
1712 } while (0)
1713
1714 #define SETUP_HOST_RD_ATTR(field, param_flag)                           \
1715 do {                                                                    \
1716         if (tt->host_param_mask & param_flag) {                         \
1717                 priv->host_attrs[count] = &dev_attr_host_##field; \
1718                 count++;                                                \
1719         }                                                               \
1720 } while (0)
1721
1722 static int iscsi_session_match(struct attribute_container *cont,
1723                            struct device *dev)
1724 {
1725         struct iscsi_cls_session *session;
1726         struct Scsi_Host *shost;
1727         struct iscsi_internal *priv;
1728
1729         if (!iscsi_is_session_dev(dev))
1730                 return 0;
1731
1732         session = iscsi_dev_to_session(dev);
1733         shost = iscsi_session_to_shost(session);
1734         if (!shost->transportt)
1735                 return 0;
1736
1737         priv = to_iscsi_internal(shost->transportt);
1738         if (priv->session_cont.ac.class != &iscsi_session_class.class)
1739                 return 0;
1740
1741         return &priv->session_cont.ac == cont;
1742 }
1743
1744 static int iscsi_conn_match(struct attribute_container *cont,
1745                            struct device *dev)
1746 {
1747         struct iscsi_cls_session *session;
1748         struct iscsi_cls_conn *conn;
1749         struct Scsi_Host *shost;
1750         struct iscsi_internal *priv;
1751
1752         if (!iscsi_is_conn_dev(dev))
1753                 return 0;
1754
1755         conn = iscsi_dev_to_conn(dev);
1756         session = iscsi_dev_to_session(conn->dev.parent);
1757         shost = iscsi_session_to_shost(session);
1758
1759         if (!shost->transportt)
1760                 return 0;
1761
1762         priv = to_iscsi_internal(shost->transportt);
1763         if (priv->conn_cont.ac.class != &iscsi_connection_class.class)
1764                 return 0;
1765
1766         return &priv->conn_cont.ac == cont;
1767 }
1768
1769 static int iscsi_host_match(struct attribute_container *cont,
1770                             struct device *dev)
1771 {
1772         struct Scsi_Host *shost;
1773         struct iscsi_internal *priv;
1774
1775         if (!scsi_is_host_device(dev))
1776                 return 0;
1777
1778         shost = dev_to_shost(dev);
1779         if (!shost->transportt  ||
1780             shost->transportt->host_attrs.ac.class != &iscsi_host_class.class)
1781                 return 0;
1782
1783         priv = to_iscsi_internal(shost->transportt);
1784         return &priv->t.host_attrs.ac == cont;
1785 }
1786
1787 struct scsi_transport_template *
1788 iscsi_register_transport(struct iscsi_transport *tt)
1789 {
1790         struct iscsi_internal *priv;
1791         unsigned long flags;
1792         int count = 0, err;
1793
1794         BUG_ON(!tt);
1795
1796         priv = iscsi_if_transport_lookup(tt);
1797         if (priv)
1798                 return NULL;
1799
1800         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1801         if (!priv)
1802                 return NULL;
1803         INIT_LIST_HEAD(&priv->list);
1804         priv->daemon_pid = -1;
1805         priv->iscsi_transport = tt;
1806         priv->t.user_scan = iscsi_user_scan;
1807         if (!(tt->caps & CAP_DATA_PATH_OFFLOAD))
1808                 priv->t.create_work_queue = 1;
1809
1810         priv->dev.class = &iscsi_transport_class;
1811         snprintf(priv->dev.bus_id, BUS_ID_SIZE, "%s", tt->name);
1812         err = device_register(&priv->dev);
1813         if (err)
1814                 goto free_priv;
1815
1816         err = sysfs_create_group(&priv->dev.kobj, &iscsi_transport_group);
1817         if (err)
1818                 goto unregister_dev;
1819
1820         /* host parameters */
1821         priv->t.host_attrs.ac.attrs = &priv->host_attrs[0];
1822         priv->t.host_attrs.ac.class = &iscsi_host_class.class;
1823         priv->t.host_attrs.ac.match = iscsi_host_match;
1824         priv->t.host_size = sizeof(struct iscsi_cls_host);
1825         transport_container_register(&priv->t.host_attrs);
1826
1827         SETUP_HOST_RD_ATTR(netdev, ISCSI_HOST_NETDEV_NAME);
1828         SETUP_HOST_RD_ATTR(ipaddress, ISCSI_HOST_IPADDRESS);
1829         SETUP_HOST_RD_ATTR(hwaddress, ISCSI_HOST_HWADDRESS);
1830         SETUP_HOST_RD_ATTR(initiatorname, ISCSI_HOST_INITIATOR_NAME);
1831         BUG_ON(count > ISCSI_HOST_ATTRS);
1832         priv->host_attrs[count] = NULL;
1833         count = 0;
1834
1835         /* connection parameters */
1836         priv->conn_cont.ac.attrs = &priv->conn_attrs[0];
1837         priv->conn_cont.ac.class = &iscsi_connection_class.class;
1838         priv->conn_cont.ac.match = iscsi_conn_match;
1839         transport_container_register(&priv->conn_cont);
1840
1841         SETUP_CONN_RD_ATTR(max_recv_dlength, ISCSI_MAX_RECV_DLENGTH);
1842         SETUP_CONN_RD_ATTR(max_xmit_dlength, ISCSI_MAX_XMIT_DLENGTH);
1843         SETUP_CONN_RD_ATTR(header_digest, ISCSI_HDRDGST_EN);
1844         SETUP_CONN_RD_ATTR(data_digest, ISCSI_DATADGST_EN);
1845         SETUP_CONN_RD_ATTR(ifmarker, ISCSI_IFMARKER_EN);
1846         SETUP_CONN_RD_ATTR(ofmarker, ISCSI_OFMARKER_EN);
1847         SETUP_CONN_RD_ATTR(address, ISCSI_CONN_ADDRESS);
1848         SETUP_CONN_RD_ATTR(port, ISCSI_CONN_PORT);
1849         SETUP_CONN_RD_ATTR(exp_statsn, ISCSI_EXP_STATSN);
1850         SETUP_CONN_RD_ATTR(persistent_address, ISCSI_PERSISTENT_ADDRESS);
1851         SETUP_CONN_RD_ATTR(persistent_port, ISCSI_PERSISTENT_PORT);
1852         SETUP_CONN_RD_ATTR(ping_tmo, ISCSI_PING_TMO);
1853         SETUP_CONN_RD_ATTR(recv_tmo, ISCSI_RECV_TMO);
1854
1855         BUG_ON(count > ISCSI_CONN_ATTRS);
1856         priv->conn_attrs[count] = NULL;
1857         count = 0;
1858
1859         /* session parameters */
1860         priv->session_cont.ac.attrs = &priv->session_attrs[0];
1861         priv->session_cont.ac.class = &iscsi_session_class.class;
1862         priv->session_cont.ac.match = iscsi_session_match;
1863         transport_container_register(&priv->session_cont);
1864
1865         SETUP_SESSION_RD_ATTR(initial_r2t, ISCSI_INITIAL_R2T_EN);
1866         SETUP_SESSION_RD_ATTR(max_outstanding_r2t, ISCSI_MAX_R2T);
1867         SETUP_SESSION_RD_ATTR(immediate_data, ISCSI_IMM_DATA_EN);
1868         SETUP_SESSION_RD_ATTR(first_burst_len, ISCSI_FIRST_BURST);
1869         SETUP_SESSION_RD_ATTR(max_burst_len, ISCSI_MAX_BURST);
1870         SETUP_SESSION_RD_ATTR(data_pdu_in_order, ISCSI_PDU_INORDER_EN);
1871         SETUP_SESSION_RD_ATTR(data_seq_in_order, ISCSI_DATASEQ_INORDER_EN);
1872         SETUP_SESSION_RD_ATTR(erl, ISCSI_ERL);
1873         SETUP_SESSION_RD_ATTR(targetname, ISCSI_TARGET_NAME);
1874         SETUP_SESSION_RD_ATTR(tpgt, ISCSI_TPGT);
1875         SETUP_SESSION_RD_ATTR(password, ISCSI_USERNAME);
1876         SETUP_SESSION_RD_ATTR(password_in, ISCSI_USERNAME_IN);
1877         SETUP_SESSION_RD_ATTR(username, ISCSI_PASSWORD);
1878         SETUP_SESSION_RD_ATTR(username_in, ISCSI_PASSWORD_IN);
1879         SETUP_SESSION_RD_ATTR(fast_abort, ISCSI_FAST_ABORT);
1880         SETUP_SESSION_RD_ATTR(abort_tmo, ISCSI_ABORT_TMO);
1881         SETUP_SESSION_RD_ATTR(lu_reset_tmo,ISCSI_LU_RESET_TMO);
1882         SETUP_SESSION_RD_ATTR(ifacename, ISCSI_IFACE_NAME);
1883         SETUP_SESSION_RD_ATTR(initiatorname, ISCSI_INITIATOR_NAME);
1884         SETUP_PRIV_SESSION_RD_ATTR(recovery_tmo);
1885         SETUP_PRIV_SESSION_RD_ATTR(state);
1886
1887         BUG_ON(count > ISCSI_SESSION_ATTRS);
1888         priv->session_attrs[count] = NULL;
1889
1890         spin_lock_irqsave(&iscsi_transport_lock, flags);
1891         list_add(&priv->list, &iscsi_transports);
1892         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1893
1894         printk(KERN_NOTICE "iscsi: registered transport (%s)\n", tt->name);
1895         return &priv->t;
1896
1897 unregister_dev:
1898         device_unregister(&priv->dev);
1899         return NULL;
1900 free_priv:
1901         kfree(priv);
1902         return NULL;
1903 }
1904 EXPORT_SYMBOL_GPL(iscsi_register_transport);
1905
1906 int iscsi_unregister_transport(struct iscsi_transport *tt)
1907 {
1908         struct iscsi_internal *priv;
1909         unsigned long flags;
1910
1911         BUG_ON(!tt);
1912
1913         mutex_lock(&rx_queue_mutex);
1914
1915         priv = iscsi_if_transport_lookup(tt);
1916         BUG_ON (!priv);
1917
1918         spin_lock_irqsave(&iscsi_transport_lock, flags);
1919         list_del(&priv->list);
1920         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1921
1922         transport_container_unregister(&priv->conn_cont);
1923         transport_container_unregister(&priv->session_cont);
1924         transport_container_unregister(&priv->t.host_attrs);
1925
1926         sysfs_remove_group(&priv->dev.kobj, &iscsi_transport_group);
1927         device_unregister(&priv->dev);
1928         mutex_unlock(&rx_queue_mutex);
1929
1930         return 0;
1931 }
1932 EXPORT_SYMBOL_GPL(iscsi_unregister_transport);
1933
1934 static __init int iscsi_transport_init(void)
1935 {
1936         int err;
1937
1938         printk(KERN_INFO "Loading iSCSI transport class v%s.\n",
1939                 ISCSI_TRANSPORT_VERSION);
1940
1941         atomic_set(&iscsi_session_nr, 0);
1942
1943         err = class_register(&iscsi_transport_class);
1944         if (err)
1945                 return err;
1946
1947         err = class_register(&iscsi_endpoint_class);
1948         if (err)
1949                 goto unregister_transport_class;
1950
1951         err = transport_class_register(&iscsi_host_class);
1952         if (err)
1953                 goto unregister_endpoint_class;
1954
1955         err = transport_class_register(&iscsi_connection_class);
1956         if (err)
1957                 goto unregister_host_class;
1958
1959         err = transport_class_register(&iscsi_session_class);
1960         if (err)
1961                 goto unregister_conn_class;
1962
1963         nls = netlink_kernel_create(&init_net, NETLINK_ISCSI, 1, iscsi_if_rx,
1964                                     NULL, THIS_MODULE);
1965         if (!nls) {
1966                 err = -ENOBUFS;
1967                 goto unregister_session_class;
1968         }
1969
1970         iscsi_eh_timer_workq = create_singlethread_workqueue("iscsi_eh");
1971         if (!iscsi_eh_timer_workq)
1972                 goto release_nls;
1973
1974         return 0;
1975
1976 release_nls:
1977         netlink_kernel_release(nls);
1978 unregister_session_class:
1979         transport_class_unregister(&iscsi_session_class);
1980 unregister_conn_class:
1981         transport_class_unregister(&iscsi_connection_class);
1982 unregister_host_class:
1983         transport_class_unregister(&iscsi_host_class);
1984 unregister_endpoint_class:
1985         class_unregister(&iscsi_endpoint_class);
1986 unregister_transport_class:
1987         class_unregister(&iscsi_transport_class);
1988         return err;
1989 }
1990
1991 static void __exit iscsi_transport_exit(void)
1992 {
1993         destroy_workqueue(iscsi_eh_timer_workq);
1994         netlink_kernel_release(nls);
1995         transport_class_unregister(&iscsi_connection_class);
1996         transport_class_unregister(&iscsi_session_class);
1997         transport_class_unregister(&iscsi_host_class);
1998         class_unregister(&iscsi_endpoint_class);
1999         class_unregister(&iscsi_transport_class);
2000 }
2001
2002 module_init(iscsi_transport_init);
2003 module_exit(iscsi_transport_exit);
2004
2005 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
2006               "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
2007               "Alex Aizman <itn780@yahoo.com>");
2008 MODULE_DESCRIPTION("iSCSI Transport Interface");
2009 MODULE_LICENSE("GPL");
2010 MODULE_VERSION(ISCSI_TRANSPORT_VERSION);