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 "2.0-870"
  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, NULL, &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 iscsi_endpoint *ep;
 223         struct device *dev;
 224
 225         dev = class_find_device(&iscsi_endpoint_class, NULL, &handle,
 226                                 iscsi_match_epid);
 227         if (!dev)
 228                 return NULL;
 229
 230         ep = iscsi_dev_to_endpoint(dev);
 231         /*
 232          * we can drop this now because the interface will prevent
 233          * removals and lookups from racing.
 234          */
 235         put_device(dev);
 236         return ep;
 237 }
 238 EXPORT_SYMBOL_GPL(iscsi_lookup_endpoint);
 239
 240 static int iscsi_setup_host(struct transport_container *tc, struct device *dev,
 241                             struct device *cdev)
 242 {
 243         struct Scsi_Host *shost = dev_to_shost(dev);
 244         struct iscsi_cls_host *ihost = shost->shost_data;
 245
 246         memset(ihost, 0, sizeof(*ihost));
 247         atomic_set(&ihost->nr_scans, 0);
 248         mutex_init(&ihost->mutex);
 249
 250         snprintf(ihost->scan_workq_name, sizeof(ihost->scan_workq_name),
 251                  "iscsi_scan_%d", shost->host_no);
 252         ihost->scan_workq = create_singlethread_workqueue(
 253                                                 ihost->scan_workq_name);
 254         if (!ihost->scan_workq)
 255                 return -ENOMEM;
 256         return 0;
 257 }
 258
 259 static int iscsi_remove_host(struct transport_container *tc, struct device *dev,
 260                              struct device *cdev)
 261 {
 262         struct Scsi_Host *shost = dev_to_shost(dev);
 263         struct iscsi_cls_host *ihost = shost->shost_data;
 264
 265         destroy_workqueue(ihost->scan_workq);
 266         return 0;
 267 }
 268
 269 static DECLARE_TRANSPORT_CLASS(iscsi_host_class,
 270                                "iscsi_host",
 271                                iscsi_setup_host,
 272                                iscsi_remove_host,
 273                                NULL);
 274
 275 static DECLARE_TRANSPORT_CLASS(iscsi_session_class,
 276                                "iscsi_session",
 277                                NULL,
 278                                NULL,
 279                                NULL);
 280
 281 static DECLARE_TRANSPORT_CLASS(iscsi_connection_class,
 282                                "iscsi_connection",
 283                                NULL,
 284                                NULL,
 285                                NULL);
 286
 287 static struct sock *nls;
 288 static DEFINE_MUTEX(rx_queue_mutex);
 289
 290 static LIST_HEAD(sesslist);
 291 static DEFINE_SPINLOCK(sesslock);
 292 static LIST_HEAD(connlist);
 293 static DEFINE_SPINLOCK(connlock);
 294
 295 static uint32_t iscsi_conn_get_sid(struct iscsi_cls_conn *conn)
 296 {
 297         struct iscsi_cls_session *sess = iscsi_dev_to_session(conn->dev.parent);
 298         return sess->sid;
 299 }
 300
 301 /*
 302  * Returns the matching session to a given sid
 303  */
 304 static struct iscsi_cls_session *iscsi_session_lookup(uint32_t sid)
 305 {
 306         unsigned long flags;
 307         struct iscsi_cls_session *sess;
 308
 309         spin_lock_irqsave(&sesslock, flags);
 310         list_for_each_entry(sess, &sesslist, sess_list) {
 311                 if (sess->sid == sid) {
 312                         spin_unlock_irqrestore(&sesslock, flags);
 313                         return sess;
 314                 }
 315         }
 316         spin_unlock_irqrestore(&sesslock, flags);
 317         return NULL;
 318 }
 319
 320 /*
 321  * Returns the matching connection to a given sid / cid tuple
 322  */
 323 static struct iscsi_cls_conn *iscsi_conn_lookup(uint32_t sid, uint32_t cid)
 324 {
 325         unsigned long flags;
 326         struct iscsi_cls_conn *conn;
 327
 328         spin_lock_irqsave(&connlock, flags);
 329         list_for_each_entry(conn, &connlist, conn_list) {
 330                 if ((conn->cid == cid) && (iscsi_conn_get_sid(conn) == sid)) {
 331                         spin_unlock_irqrestore(&connlock, flags);
 332                         return conn;
 333                 }
 334         }
 335         spin_unlock_irqrestore(&connlock, flags);
 336         return NULL;
 337 }
 338
 339 /*
 340  * The following functions can be used by LLDs that allocate
 341  * their own scsi_hosts or by software iscsi LLDs
 342  */
 343 static struct {
 344         int value;
 345         char *name;
 346 } iscsi_session_state_names[] = {
 347         { ISCSI_SESSION_LOGGED_IN,      "LOGGED_IN" },
 348         { ISCSI_SESSION_FAILED,         "FAILED" },
 349         { ISCSI_SESSION_FREE,           "FREE" },
 350 };
 351
 352 static const char *iscsi_session_state_name(int state)
 353 {
 354         int i;
 355         char *name = NULL;
 356
 357         for (i = 0; i < ARRAY_SIZE(iscsi_session_state_names); i++) {
 358                 if (iscsi_session_state_names[i].value == state) {
 359                         name = iscsi_session_state_names[i].name;
 360                         break;
 361                 }
 362         }
 363         return name;
 364 }
 365
 366 int iscsi_session_chkready(struct iscsi_cls_session *session)
 367 {
 368         unsigned long flags;
 369         int err;
 370
 371         spin_lock_irqsave(&session->lock, flags);
 372         switch (session->state) {
 373         case ISCSI_SESSION_LOGGED_IN:
 374                 err = 0;
 375                 break;
 376         case ISCSI_SESSION_FAILED:
 377                 err = DID_IMM_RETRY << 16;
 378                 break;
 379         case ISCSI_SESSION_FREE:
 380                 err = DID_NO_CONNECT << 16;
 381                 break;
 382         default:
 383                 err = DID_NO_CONNECT << 16;
 384                 break;
 385         }
 386         spin_unlock_irqrestore(&session->lock, flags);
 387         return err;
 388 }
 389 EXPORT_SYMBOL_GPL(iscsi_session_chkready);
 390
 391 static void iscsi_session_release(struct device *dev)
 392 {
 393         struct iscsi_cls_session *session = iscsi_dev_to_session(dev);
 394         struct Scsi_Host *shost;
 395
 396         shost = iscsi_session_to_shost(session);
 397         scsi_host_put(shost);
 398         kfree(session);
 399 }
 400
 401 static int iscsi_is_session_dev(const struct device *dev)
 402 {
 403         return dev->release == iscsi_session_release;
 404 }
 405
 406 static int iscsi_iter_session_fn(struct device *dev, void *data)
 407 {
 408         void (* fn) (struct iscsi_cls_session *) = data;
 409
 410         if (!iscsi_is_session_dev(dev))
 411                 return 0;
 412         fn(iscsi_dev_to_session(dev));
 413         return 0;
 414 }
 415
 416 void iscsi_host_for_each_session(struct Scsi_Host *shost,
 417                                  void (*fn)(struct iscsi_cls_session *))
 418 {
 419         device_for_each_child(&shost->shost_gendev, fn,
 420                               iscsi_iter_session_fn);
 421 }
 422 EXPORT_SYMBOL_GPL(iscsi_host_for_each_session);
 423
 424 /**
 425  * iscsi_scan_finished - helper to report when running scans are done
 426  * @shost: scsi host
 427  * @time: scan run time
 428  *
 429  * This function can be used by drives like qla4xxx to report to the scsi
 430  * layer when the scans it kicked off at module load time are done.
 431  */
 432 int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time)
 433 {
 434         struct iscsi_cls_host *ihost = shost->shost_data;
 435         /*
 436          * qla4xxx will have kicked off some session unblocks before calling
 437          * scsi_scan_host, so just wait for them to complete.
 438          */
 439         return !atomic_read(&ihost->nr_scans);
 440 }
 441 EXPORT_SYMBOL_GPL(iscsi_scan_finished);
 442
 443 struct iscsi_scan_data {
 444         unsigned int channel;
 445         unsigned int id;
 446         unsigned int lun;
 447 };
 448
 449 static int iscsi_user_scan_session(struct device *dev, void *data)
 450 {
 451         struct iscsi_scan_data *scan_data = data;
 452         struct iscsi_cls_session *session;
 453         struct Scsi_Host *shost;
 454         struct iscsi_cls_host *ihost;
 455         unsigned long flags;
 456         unsigned int id;
 457
 458         if (!iscsi_is_session_dev(dev))
 459                 return 0;
 460
 461         session = iscsi_dev_to_session(dev);
 462         shost = iscsi_session_to_shost(session);
 463         ihost = shost->shost_data;
 464
 465         mutex_lock(&ihost->mutex);
 466         spin_lock_irqsave(&session->lock, flags);
 467         if (session->state != ISCSI_SESSION_LOGGED_IN) {
 468                 spin_unlock_irqrestore(&session->lock, flags);
 469                 mutex_unlock(&ihost->mutex);
 470                 return 0;
 471         }
 472         id = session->target_id;
 473         spin_unlock_irqrestore(&session->lock, flags);
 474
 475         if (id != ISCSI_MAX_TARGET) {
 476                 if ((scan_data->channel == SCAN_WILD_CARD ||
 477                      scan_data->channel == 0) &&
 478                     (scan_data->id == SCAN_WILD_CARD ||
 479                      scan_data->id == id))
 480                         scsi_scan_target(&session->dev, 0, id,
 481                                          scan_data->lun, 1);
 482         }
 483         mutex_unlock(&ihost->mutex);
 484         return 0;
 485 }
 486
 487 static int iscsi_user_scan(struct Scsi_Host *shost, uint channel,
 488                            uint id, uint lun)
 489 {
 490         struct iscsi_scan_data scan_data;
 491
 492         scan_data.channel = channel;
 493         scan_data.id = id;
 494         scan_data.lun = lun;
 495
 496         return device_for_each_child(&shost->shost_gendev, &scan_data,
 497                                      iscsi_user_scan_session);
 498 }
 499
 500 static void iscsi_scan_session(struct work_struct *work)
 501 {
 502         struct iscsi_cls_session *session =
 503                         container_of(work, struct iscsi_cls_session, scan_work);
 504         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 505         struct iscsi_cls_host *ihost = shost->shost_data;
 506         struct iscsi_scan_data scan_data;
 507
 508         scan_data.channel = 0;
 509         scan_data.id = SCAN_WILD_CARD;
 510         scan_data.lun = SCAN_WILD_CARD;
 511
 512         iscsi_user_scan_session(&session->dev, &scan_data);
 513         atomic_dec(&ihost->nr_scans);
 514 }
 515
 516 static void session_recovery_timedout(struct work_struct *work)
 517 {
 518         struct iscsi_cls_session *session =
 519                 container_of(work, struct iscsi_cls_session,
 520                              recovery_work.work);
 521         unsigned long flags;
 522
 523         iscsi_cls_session_printk(KERN_INFO, session,
 524                                  "session recovery timed out after %d secs\n",
 525                                  session->recovery_tmo);
 526
 527         spin_lock_irqsave(&session->lock, flags);
 528         switch (session->state) {
 529         case ISCSI_SESSION_FAILED:
 530                 session->state = ISCSI_SESSION_FREE;
 531                 break;
 532         case ISCSI_SESSION_LOGGED_IN:
 533         case ISCSI_SESSION_FREE:
 534                 /* we raced with the unblock's flush */
 535                 spin_unlock_irqrestore(&session->lock, flags);
 536                 return;
 537         }
 538         spin_unlock_irqrestore(&session->lock, flags);
 539
 540         if (session->transport->session_recovery_timedout)
 541                 session->transport->session_recovery_timedout(session);
 542
 543         scsi_target_unblock(&session->dev);
 544 }
 545
 546 static void __iscsi_unblock_session(struct work_struct *work)
 547 {
 548         struct iscsi_cls_session *session =
 549                         container_of(work, struct iscsi_cls_session,
 550                                      unblock_work);
 551         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 552         struct iscsi_cls_host *ihost = shost->shost_data;
 553         unsigned long flags;
 554
 555         /*
 556          * The recovery and unblock work get run from the same workqueue,
 557          * so try to cancel it if it was going to run after this unblock.
 558          */
 559         cancel_delayed_work(&session->recovery_work);
 560         spin_lock_irqsave(&session->lock, flags);
 561         session->state = ISCSI_SESSION_LOGGED_IN;
 562         spin_unlock_irqrestore(&session->lock, flags);
 563         /* start IO */
 564         scsi_target_unblock(&session->dev);
 565         /*
 566          * Only do kernel scanning if the driver is properly hooked into
 567          * the async scanning code (drivers like iscsi_tcp do login and
 568          * scanning from userspace).
 569          */
 570         if (shost->hostt->scan_finished) {
 571                 if (queue_work(ihost->scan_workq, &session->scan_work))
 572                         atomic_inc(&ihost->nr_scans);
 573         }
 574 }
 575
 576 /**
 577  * iscsi_unblock_session - set a session as logged in and start IO.
 578  * @session: iscsi session
 579  *
 580  * Mark a session as ready to accept IO.
 581  */
 582 void iscsi_unblock_session(struct iscsi_cls_session *session)
 583 {
 584         queue_work(iscsi_eh_timer_workq, &session->unblock_work);
 585         /*
 586          * make sure all the events have completed before tell the driver
 587          * it is safe
 588          */
 589         flush_workqueue(iscsi_eh_timer_workq);
 590 }
 591 EXPORT_SYMBOL_GPL(iscsi_unblock_session);
 592
 593 static void __iscsi_block_session(struct work_struct *work)
 594 {
 595         struct iscsi_cls_session *session =
 596                         container_of(work, struct iscsi_cls_session,
 597                                      block_work);
 598         unsigned long flags;
 599
 600         spin_lock_irqsave(&session->lock, flags);
 601         session->state = ISCSI_SESSION_FAILED;
 602         spin_unlock_irqrestore(&session->lock, flags);
 603         scsi_target_block(&session->dev);
 604         queue_delayed_work(iscsi_eh_timer_workq, &session->recovery_work,
 605                            session->recovery_tmo * HZ);
 606 }
 607
 608 void iscsi_block_session(struct iscsi_cls_session *session)
 609 {
 610         queue_work(iscsi_eh_timer_workq, &session->block_work);
 611 }
 612 EXPORT_SYMBOL_GPL(iscsi_block_session);
 613
 614 static void __iscsi_unbind_session(struct work_struct *work)
 615 {
 616         struct iscsi_cls_session *session =
 617                         container_of(work, struct iscsi_cls_session,
 618                                      unbind_work);
 619         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 620         struct iscsi_cls_host *ihost = shost->shost_data;
 621         unsigned long flags;
 622
 623         /* Prevent new scans and make sure scanning is not in progress */
 624         mutex_lock(&ihost->mutex);
 625         spin_lock_irqsave(&session->lock, flags);
 626         if (session->target_id == ISCSI_MAX_TARGET) {
 627                 spin_unlock_irqrestore(&session->lock, flags);
 628                 mutex_unlock(&ihost->mutex);
 629                 return;
 630         }
 631         session->target_id = ISCSI_MAX_TARGET;
 632         spin_unlock_irqrestore(&session->lock, flags);
 633         mutex_unlock(&ihost->mutex);
 634
 635         scsi_remove_target(&session->dev);
 636         iscsi_session_event(session, ISCSI_KEVENT_UNBIND_SESSION);
 637 }
 638
 639 static int iscsi_unbind_session(struct iscsi_cls_session *session)
 640 {
 641         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 642         struct iscsi_cls_host *ihost = shost->shost_data;
 643
 644         return queue_work(ihost->scan_workq, &session->unbind_work);
 645 }
 646
 647 struct iscsi_cls_session *
 648 iscsi_alloc_session(struct Scsi_Host *shost, struct iscsi_transport *transport,
 649                     int dd_size)
 650 {
 651         struct iscsi_cls_session *session;
 652
 653         session = kzalloc(sizeof(*session) + dd_size,
 654                           GFP_KERNEL);
 655         if (!session)
 656                 return NULL;
 657
 658         session->transport = transport;
 659         session->recovery_tmo = 120;
 660         session->state = ISCSI_SESSION_FREE;
 661         INIT_DELAYED_WORK(&session->recovery_work, session_recovery_timedout);
 662         INIT_LIST_HEAD(&session->sess_list);
 663         INIT_WORK(&session->unblock_work, __iscsi_unblock_session);
 664         INIT_WORK(&session->block_work, __iscsi_block_session);
 665         INIT_WORK(&session->unbind_work, __iscsi_unbind_session);
 666         INIT_WORK(&session->scan_work, iscsi_scan_session);
 667         spin_lock_init(&session->lock);
 668
 669         /* this is released in the dev's release function */
 670         scsi_host_get(shost);
 671         session->dev.parent = &shost->shost_gendev;
 672         session->dev.release = iscsi_session_release;
 673         device_initialize(&session->dev);
 674         if (dd_size)
 675                 session->dd_data = &session[1];
 676         return session;
 677 }
 678 EXPORT_SYMBOL_GPL(iscsi_alloc_session);
 679
 680 static int iscsi_get_next_target_id(struct device *dev, void *data)
 681 {
 682         struct iscsi_cls_session *session;
 683         unsigned long flags;
 684         int err = 0;
 685
 686         if (!iscsi_is_session_dev(dev))
 687                 return 0;
 688
 689         session = iscsi_dev_to_session(dev);
 690         spin_lock_irqsave(&session->lock, flags);
 691         if (*((unsigned int *) data) == session->target_id)
 692                 err = -EEXIST;
 693         spin_unlock_irqrestore(&session->lock, flags);
 694         return err;
 695 }
 696
 697 int iscsi_add_session(struct iscsi_cls_session *session, unsigned int target_id)
 698 {
 699         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 700         struct iscsi_cls_host *ihost;
 701         unsigned long flags;
 702         unsigned int id = target_id;
 703         int err;
 704
 705         ihost = shost->shost_data;
 706         session->sid = atomic_add_return(1, &iscsi_session_nr);
 707
 708         if (id == ISCSI_MAX_TARGET) {
 709                 for (id = 0; id < ISCSI_MAX_TARGET; id++) {
 710                         err = device_for_each_child(&shost->shost_gendev, &id,
 711                                                     iscsi_get_next_target_id);
 712                         if (!err)
 713                                 break;
 714                 }
 715
 716                 if (id == ISCSI_MAX_TARGET) {
 717                         iscsi_cls_session_printk(KERN_ERR, session,
 718                                                  "Too many iscsi targets. Max "
 719                                                  "number of targets is %d.\n",
 720                                                  ISCSI_MAX_TARGET - 1);
 721                         goto release_host;
 722                 }
 723         }
 724         session->target_id = id;
 725
 726         snprintf(session->dev.bus_id, BUS_ID_SIZE, "session%u",
 727                  session->sid);
 728         err = device_add(&session->dev);
 729         if (err) {
 730                 iscsi_cls_session_printk(KERN_ERR, session,
 731                                          "could not register session's dev\n");
 732                 goto release_host;
 733         }
 734         transport_register_device(&session->dev);
 735
 736         spin_lock_irqsave(&sesslock, flags);
 737         list_add(&session->sess_list, &sesslist);
 738         spin_unlock_irqrestore(&sesslock, flags);
 739
 740         iscsi_session_event(session, ISCSI_KEVENT_CREATE_SESSION);
 741         return 0;
 742
 743 release_host:
 744         scsi_host_put(shost);
 745         return err;
 746 }
 747 EXPORT_SYMBOL_GPL(iscsi_add_session);
 748
 749 /**
 750  * iscsi_create_session - create iscsi class session
 751  * @shost: scsi host
 752  * @transport: iscsi transport
 753  * @dd_size: private driver data size
 754  * @target_id: which target
 755  *
 756  * This can be called from a LLD or iscsi_transport.
 757  */
 758 struct iscsi_cls_session *
 759 iscsi_create_session(struct Scsi_Host *shost, struct iscsi_transport *transport,
 760                      int dd_size, unsigned int target_id)
 761 {
 762         struct iscsi_cls_session *session;
 763
 764         session = iscsi_alloc_session(shost, transport, dd_size);
 765         if (!session)
 766                 return NULL;
 767
 768         if (iscsi_add_session(session, target_id)) {
 769                 iscsi_free_session(session);
 770                 return NULL;
 771         }
 772         return session;
 773 }
 774 EXPORT_SYMBOL_GPL(iscsi_create_session);
 775
 776 static void iscsi_conn_release(struct device *dev)
 777 {
 778         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev);
 779         struct device *parent = conn->dev.parent;
 780
 781         kfree(conn);
 782         put_device(parent);
 783 }
 784
 785 static int iscsi_is_conn_dev(const struct device *dev)
 786 {
 787         return dev->release == iscsi_conn_release;
 788 }
 789
 790 static int iscsi_iter_destroy_conn_fn(struct device *dev, void *data)
 791 {
 792         if (!iscsi_is_conn_dev(dev))
 793                 return 0;
 794         return iscsi_destroy_conn(iscsi_dev_to_conn(dev));
 795 }
 796
 797 void iscsi_remove_session(struct iscsi_cls_session *session)
 798 {
 799         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 800         struct iscsi_cls_host *ihost = shost->shost_data;
 801         unsigned long flags;
 802         int err;
 803
 804         spin_lock_irqsave(&sesslock, flags);
 805         list_del(&session->sess_list);
 806         spin_unlock_irqrestore(&sesslock, flags);
 807
 808         /* make sure there are no blocks/unblocks queued */
 809         flush_workqueue(iscsi_eh_timer_workq);
 810         /* make sure the timedout callout is not running */
 811         if (!cancel_delayed_work(&session->recovery_work))
 812                 flush_workqueue(iscsi_eh_timer_workq);
 813         /*
 814          * If we are blocked let commands flow again. The lld or iscsi
 815          * layer should set up the queuecommand to fail commands.
 816          * We assume that LLD will not be calling block/unblock while
 817          * removing the session.
 818          */
 819         spin_lock_irqsave(&session->lock, flags);
 820         session->state = ISCSI_SESSION_FREE;
 821         spin_unlock_irqrestore(&session->lock, flags);
 822
 823         scsi_target_unblock(&session->dev);
 824         /* flush running scans then delete devices */
 825         flush_workqueue(ihost->scan_workq);
 826         __iscsi_unbind_session(&session->unbind_work);
 827
 828         /* hw iscsi may not have removed all connections from session */
 829         err = device_for_each_child(&session->dev, NULL,
 830                                     iscsi_iter_destroy_conn_fn);
 831         if (err)
 832                 iscsi_cls_session_printk(KERN_ERR, session,
 833                                          "Could not delete all connections "
 834                                          "for session. Error %d.\n", err);
 835
 836         transport_unregister_device(&session->dev);
 837         device_del(&session->dev);
 838 }
 839 EXPORT_SYMBOL_GPL(iscsi_remove_session);
 840
 841 void iscsi_free_session(struct iscsi_cls_session *session)
 842 {
 843         iscsi_session_event(session, ISCSI_KEVENT_DESTROY_SESSION);
 844         put_device(&session->dev);
 845 }
 846 EXPORT_SYMBOL_GPL(iscsi_free_session);
 847
 848 /**
 849  * iscsi_destroy_session - destroy iscsi session
 850  * @session: iscsi_session
 851  *
 852  * Can be called by a LLD or iscsi_transport. There must not be
 853  * any running connections.
 854  */
 855 int iscsi_destroy_session(struct iscsi_cls_session *session)
 856 {
 857         iscsi_remove_session(session);
 858         iscsi_free_session(session);
 859         return 0;
 860 }
 861 EXPORT_SYMBOL_GPL(iscsi_destroy_session);
 862
 863 /**
 864  * iscsi_create_conn - create iscsi class connection
 865  * @session: iscsi cls session
 866  * @dd_size: private driver data size
 867  * @cid: connection id
 868  *
 869  * This can be called from a LLD or iscsi_transport. The connection
 870  * is child of the session so cid must be unique for all connections
 871  * on the session.
 872  *
 873  * Since we do not support MCS, cid will normally be zero. In some cases
 874  * for software iscsi we could be trying to preallocate a connection struct
 875  * in which case there could be two connection structs and cid would be
 876  * non-zero.
 877  */
 878 struct iscsi_cls_conn *
 879 iscsi_create_conn(struct iscsi_cls_session *session, int dd_size, uint32_t cid)
 880 {
 881         struct iscsi_transport *transport = session->transport;
 882         struct iscsi_cls_conn *conn;
 883         unsigned long flags;
 884         int err;
 885
 886         conn = kzalloc(sizeof(*conn) + dd_size, GFP_KERNEL);
 887         if (!conn)
 888                 return NULL;
 889         if (dd_size)
 890                 conn->dd_data = &conn[1];
 891
 892         INIT_LIST_HEAD(&conn->conn_list);
 893         conn->transport = transport;
 894         conn->cid = cid;
 895
 896         /* this is released in the dev's release function */
 897         if (!get_device(&session->dev))
 898                 goto free_conn;
 899
 900         snprintf(conn->dev.bus_id, BUS_ID_SIZE, "connection%d:%u",
 901                  session->sid, cid);
 902         conn->dev.parent = &session->dev;
 903         conn->dev.release = iscsi_conn_release;
 904         err = device_register(&conn->dev);
 905         if (err) {
 906                 iscsi_cls_session_printk(KERN_ERR, session, "could not "
 907                                          "register connection's dev\n");
 908                 goto release_parent_ref;
 909         }
 910         transport_register_device(&conn->dev);
 911
 912         spin_lock_irqsave(&connlock, flags);
 913         list_add(&conn->conn_list, &connlist);
 914         conn->active = 1;
 915         spin_unlock_irqrestore(&connlock, flags);
 916         return conn;
 917
 918 release_parent_ref:
 919         put_device(&session->dev);
 920 free_conn:
 921         kfree(conn);
 922         return NULL;
 923 }
 924
 925 EXPORT_SYMBOL_GPL(iscsi_create_conn);
 926
 927 /**
 928  * iscsi_destroy_conn - destroy iscsi class connection
 929  * @conn: iscsi cls session
 930  *
 931  * This can be called from a LLD or iscsi_transport.
 932  */
 933 int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
 934 {
 935         unsigned long flags;
 936
 937         spin_lock_irqsave(&connlock, flags);
 938         conn->active = 0;
 939         list_del(&conn->conn_list);
 940         spin_unlock_irqrestore(&connlock, flags);
 941
 942         transport_unregister_device(&conn->dev);
 943         device_unregister(&conn->dev);
 944         return 0;
 945 }
 946 EXPORT_SYMBOL_GPL(iscsi_destroy_conn);
 947
 948 /*
 949  * iscsi interface functions
 950  */
 951 static struct iscsi_internal *
 952 iscsi_if_transport_lookup(struct iscsi_transport *tt)
 953 {
 954         struct iscsi_internal *priv;
 955         unsigned long flags;
 956
 957         spin_lock_irqsave(&iscsi_transport_lock, flags);
 958         list_for_each_entry(priv, &iscsi_transports, list) {
 959                 if (tt == priv->iscsi_transport) {
 960                         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 961                         return priv;
 962                 }
 963         }
 964         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 965         return NULL;
 966 }
 967
 968 static int
 969 iscsi_broadcast_skb(struct sk_buff *skb, gfp_t gfp)
 970 {
 971         int rc;
 972
 973         rc = netlink_broadcast(nls, skb, 0, 1, gfp);
 974         if (rc < 0) {
 975                 printk(KERN_ERR "iscsi: can not broadcast skb (%d)\n", rc);
 976                 return rc;
 977         }
 978
 979         return 0;
 980 }
 981
 982 static int
 983 iscsi_unicast_skb(struct sk_buff *skb, int pid)
 984 {
 985         int rc;
 986
 987         rc = netlink_unicast(nls, skb, pid, MSG_DONTWAIT);
 988         if (rc < 0) {
 989                 printk(KERN_ERR "iscsi: can not unicast skb (%d)\n", rc);
 990                 return rc;
 991         }
 992
 993         return 0;
 994 }
 995
 996 int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
 997                    char *data, uint32_t data_size)
 998 {
 999         struct nlmsghdr *nlh;
1000         struct sk_buff *skb;
1001         struct iscsi_uevent *ev;
1002         char *pdu;
1003         struct iscsi_internal *priv;
1004         int len = NLMSG_SPACE(sizeof(*ev) + sizeof(struct iscsi_hdr) +
1005                               data_size);
1006
1007         priv = iscsi_if_transport_lookup(conn->transport);
1008         if (!priv)
1009                 return -EINVAL;
1010
1011         skb = alloc_skb(len, GFP_ATOMIC);
1012         if (!skb) {
1013                 iscsi_conn_error(conn, ISCSI_ERR_CONN_FAILED);
1014                 iscsi_cls_conn_printk(KERN_ERR, conn, "can not deliver "
1015                                       "control PDU: OOM\n");
1016                 return -ENOMEM;
1017         }
1018
1019         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
1020         ev = NLMSG_DATA(nlh);
1021         memset(ev, 0, sizeof(*ev));
1022         ev->transport_handle = iscsi_handle(conn->transport);
1023         ev->type = ISCSI_KEVENT_RECV_PDU;
1024         ev->r.recv_req.cid = conn->cid;
1025         ev->r.recv_req.sid = iscsi_conn_get_sid(conn);
1026         pdu = (char*)ev + sizeof(*ev);
1027         memcpy(pdu, hdr, sizeof(struct iscsi_hdr));
1028         memcpy(pdu + sizeof(struct iscsi_hdr), data, data_size);
1029
1030         return iscsi_unicast_skb(skb, priv->daemon_pid);
1031 }
1032 EXPORT_SYMBOL_GPL(iscsi_recv_pdu);
1033
1034 void iscsi_conn_error(struct iscsi_cls_conn *conn, enum iscsi_err error)
1035 {
1036         struct nlmsghdr *nlh;
1037         struct sk_buff  *skb;
1038         struct iscsi_uevent *ev;
1039         struct iscsi_internal *priv;
1040         int len = NLMSG_SPACE(sizeof(*ev));
1041
1042         priv = iscsi_if_transport_lookup(conn->transport);
1043         if (!priv)
1044                 return;
1045
1046         skb = alloc_skb(len, GFP_ATOMIC);
1047         if (!skb) {
1048                 iscsi_cls_conn_printk(KERN_ERR, conn, "gracefully ignored "
1049                                       "conn error (%d)\n", error);
1050                 return;
1051         }
1052
1053         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
1054         ev = NLMSG_DATA(nlh);
1055         ev->transport_handle = iscsi_handle(conn->transport);
1056         ev->type = ISCSI_KEVENT_CONN_ERROR;
1057         ev->r.connerror.error = error;
1058         ev->r.connerror.cid = conn->cid;
1059         ev->r.connerror.sid = iscsi_conn_get_sid(conn);
1060
1061         iscsi_broadcast_skb(skb, GFP_ATOMIC);
1062
1063         iscsi_cls_conn_printk(KERN_INFO, conn, "detected conn error (%d)\n",
1064                               error);
1065 }
1066 EXPORT_SYMBOL_GPL(iscsi_conn_error);
1067
1068 static int
1069 iscsi_if_send_reply(int pid, int seq, int type, int done, int multi,
1070                       void *payload, int size)
1071 {
1072         struct sk_buff  *skb;
1073         struct nlmsghdr *nlh;
1074         int len = NLMSG_SPACE(size);
1075         int flags = multi ? NLM_F_MULTI : 0;
1076         int t = done ? NLMSG_DONE : type;
1077
1078         skb = alloc_skb(len, GFP_ATOMIC);
1079         if (!skb) {
1080                 printk(KERN_ERR "Could not allocate skb to send reply.\n");
1081                 return -ENOMEM;
1082         }
1083
1084         nlh = __nlmsg_put(skb, pid, seq, t, (len - sizeof(*nlh)), 0);
1085         nlh->nlmsg_flags = flags;
1086         memcpy(NLMSG_DATA(nlh), payload, size);
1087         return iscsi_unicast_skb(skb, pid);
1088 }
1089
1090 static int
1091 iscsi_if_get_stats(struct iscsi_transport *transport, struct nlmsghdr *nlh)
1092 {
1093         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1094         struct iscsi_stats *stats;
1095         struct sk_buff *skbstat;
1096         struct iscsi_cls_conn *conn;
1097         struct nlmsghdr *nlhstat;
1098         struct iscsi_uevent *evstat;
1099         struct iscsi_internal *priv;
1100         int len = NLMSG_SPACE(sizeof(*ev) +
1101                               sizeof(struct iscsi_stats) +
1102                               sizeof(struct iscsi_stats_custom) *
1103                               ISCSI_STATS_CUSTOM_MAX);
1104         int err = 0;
1105
1106         priv = iscsi_if_transport_lookup(transport);
1107         if (!priv)
1108                 return -EINVAL;
1109
1110         conn = iscsi_conn_lookup(ev->u.get_stats.sid, ev->u.get_stats.cid);
1111         if (!conn)
1112                 return -EEXIST;
1113
1114         do {
1115                 int actual_size;
1116
1117                 skbstat = alloc_skb(len, GFP_ATOMIC);
1118                 if (!skbstat) {
1119                         iscsi_cls_conn_printk(KERN_ERR, conn, "can not "
1120                                               "deliver stats: OOM\n");
1121                         return -ENOMEM;
1122                 }
1123
1124                 nlhstat = __nlmsg_put(skbstat, priv->daemon_pid, 0, 0,
1125                                       (len - sizeof(*nlhstat)), 0);
1126                 evstat = NLMSG_DATA(nlhstat);
1127                 memset(evstat, 0, sizeof(*evstat));
1128                 evstat->transport_handle = iscsi_handle(conn->transport);
1129                 evstat->type = nlh->nlmsg_type;
1130                 evstat->u.get_stats.cid =
1131                         ev->u.get_stats.cid;
1132                 evstat->u.get_stats.sid =
1133                         ev->u.get_stats.sid;
1134                 stats = (struct iscsi_stats *)
1135                         ((char*)evstat + sizeof(*evstat));
1136                 memset(stats, 0, sizeof(*stats));
1137
1138                 transport->get_stats(conn, stats);
1139                 actual_size = NLMSG_SPACE(sizeof(struct iscsi_uevent) +
1140                                           sizeof(struct iscsi_stats) +
1141                                           sizeof(struct iscsi_stats_custom) *
1142                                           stats->custom_length);
1143                 actual_size -= sizeof(*nlhstat);
1144                 actual_size = NLMSG_LENGTH(actual_size);
1145                 skb_trim(skbstat, NLMSG_ALIGN(actual_size));
1146                 nlhstat->nlmsg_len = actual_size;
1147
1148                 err = iscsi_unicast_skb(skbstat, priv->daemon_pid);
1149         } while (err < 0 && err != -ECONNREFUSED);
1150
1151         return err;
1152 }
1153
1154 /**
1155  * iscsi_session_event - send session destr. completion event
1156  * @session: iscsi class session
1157  * @event: type of event
1158  */
1159 int iscsi_session_event(struct iscsi_cls_session *session,
1160                         enum iscsi_uevent_e event)
1161 {
1162         struct iscsi_internal *priv;
1163         struct Scsi_Host *shost;
1164         struct iscsi_uevent *ev;
1165         struct sk_buff  *skb;
1166         struct nlmsghdr *nlh;
1167         int rc, len = NLMSG_SPACE(sizeof(*ev));
1168
1169         priv = iscsi_if_transport_lookup(session->transport);
1170         if (!priv)
1171                 return -EINVAL;
1172         shost = iscsi_session_to_shost(session);
1173
1174         skb = alloc_skb(len, GFP_KERNEL);
1175         if (!skb) {
1176                 iscsi_cls_session_printk(KERN_ERR, session,
1177                                          "Cannot notify userspace of session "
1178                                          "event %u\n", event);
1179                 return -ENOMEM;
1180         }
1181
1182         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
1183         ev = NLMSG_DATA(nlh);
1184         ev->transport_handle = iscsi_handle(session->transport);
1185
1186         ev->type = event;
1187         switch (event) {
1188         case ISCSI_KEVENT_DESTROY_SESSION:
1189                 ev->r.d_session.host_no = shost->host_no;
1190                 ev->r.d_session.sid = session->sid;
1191                 break;
1192         case ISCSI_KEVENT_CREATE_SESSION:
1193                 ev->r.c_session_ret.host_no = shost->host_no;
1194                 ev->r.c_session_ret.sid = session->sid;
1195                 break;
1196         case ISCSI_KEVENT_UNBIND_SESSION:
1197                 ev->r.unbind_session.host_no = shost->host_no;
1198                 ev->r.unbind_session.sid = session->sid;
1199                 break;
1200         default:
1201                 iscsi_cls_session_printk(KERN_ERR, session, "Invalid event "
1202                                          "%u.\n", event);
1203                 kfree_skb(skb);
1204                 return -EINVAL;
1205         }
1206
1207         /*
1208          * this will occur if the daemon is not up, so we just warn
1209          * the user and when the daemon is restarted it will handle it
1210          */
1211         rc = iscsi_broadcast_skb(skb, GFP_KERNEL);
1212         if (rc < 0)
1213                 iscsi_cls_session_printk(KERN_ERR, session,
1214                                          "Cannot notify userspace of session "
1215                                          "event %u. Check iscsi daemon\n",
1216                                          event);
1217         return rc;
1218 }
1219 EXPORT_SYMBOL_GPL(iscsi_session_event);
1220
1221 static int
1222 iscsi_if_create_session(struct iscsi_internal *priv, struct iscsi_endpoint *ep,
1223                         struct iscsi_uevent *ev, uint32_t initial_cmdsn,
1224                         uint16_t cmds_max, uint16_t queue_depth)
1225 {
1226         struct iscsi_transport *transport = priv->iscsi_transport;
1227         struct iscsi_cls_session *session;
1228         uint32_t host_no;
1229
1230         session = transport->create_session(ep, cmds_max, queue_depth,
1231                                             initial_cmdsn, &host_no);
1232         if (!session)
1233                 return -ENOMEM;
1234
1235         ev->r.c_session_ret.host_no = host_no;
1236         ev->r.c_session_ret.sid = session->sid;
1237         return 0;
1238 }
1239
1240 static int
1241 iscsi_if_create_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1242 {
1243         struct iscsi_cls_conn *conn;
1244         struct iscsi_cls_session *session;
1245
1246         session = iscsi_session_lookup(ev->u.c_conn.sid);
1247         if (!session) {
1248                 printk(KERN_ERR "iscsi: invalid session %d.\n",
1249                        ev->u.c_conn.sid);
1250                 return -EINVAL;
1251         }
1252
1253         conn = transport->create_conn(session, ev->u.c_conn.cid);
1254         if (!conn) {
1255                 iscsi_cls_session_printk(KERN_ERR, session,
1256                                          "couldn't create a new connection.");
1257                 return -ENOMEM;
1258         }
1259
1260         ev->r.c_conn_ret.sid = session->sid;
1261         ev->r.c_conn_ret.cid = conn->cid;
1262         return 0;
1263 }
1264
1265 static int
1266 iscsi_if_destroy_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1267 {
1268         struct iscsi_cls_conn *conn;
1269
1270         conn = iscsi_conn_lookup(ev->u.d_conn.sid, ev->u.d_conn.cid);
1271         if (!conn)
1272                 return -EINVAL;
1273
1274         if (transport->destroy_conn)
1275                 transport->destroy_conn(conn);
1276         return 0;
1277 }
1278
1279 static int
1280 iscsi_set_param(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1281 {
1282         char *data = (char*)ev + sizeof(*ev);
1283         struct iscsi_cls_conn *conn;
1284         struct iscsi_cls_session *session;
1285         int err = 0, value = 0;
1286
1287         session = iscsi_session_lookup(ev->u.set_param.sid);
1288         conn = iscsi_conn_lookup(ev->u.set_param.sid, ev->u.set_param.cid);
1289         if (!conn || !session)
1290                 return -EINVAL;
1291
1292         switch (ev->u.set_param.param) {
1293         case ISCSI_PARAM_SESS_RECOVERY_TMO:
1294                 sscanf(data, "%d", &value);
1295                 if (value != 0)
1296                         session->recovery_tmo = value;
1297                 break;
1298         default:
1299                 err = transport->set_param(conn, ev->u.set_param.param,
1300                                            data, ev->u.set_param.len);
1301         }
1302
1303         return err;
1304 }
1305
1306 static int
1307 iscsi_if_transport_ep(struct iscsi_transport *transport,
1308                       struct iscsi_uevent *ev, int msg_type)
1309 {
1310         struct iscsi_endpoint *ep;
1311         struct sockaddr *dst_addr;
1312         int rc = 0;
1313
1314         switch (msg_type) {
1315         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1316                 if (!transport->ep_connect)
1317                         return -EINVAL;
1318
1319                 dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1320                 ep = transport->ep_connect(dst_addr,
1321                                            ev->u.ep_connect.non_blocking);
1322                 if (IS_ERR(ep))
1323                         return PTR_ERR(ep);
1324
1325                 ev->r.ep_connect_ret.handle = ep->id;
1326                 break;
1327         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1328                 if (!transport->ep_poll)
1329                         return -EINVAL;
1330
1331                 ep = iscsi_lookup_endpoint(ev->u.ep_poll.ep_handle);
1332                 if (!ep)
1333                         return -EINVAL;
1334
1335                 ev->r.retcode = transport->ep_poll(ep,
1336                                                    ev->u.ep_poll.timeout_ms);
1337                 break;
1338         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1339                 if (!transport->ep_disconnect)
1340                         return -EINVAL;
1341
1342                 ep = iscsi_lookup_endpoint(ev->u.ep_disconnect.ep_handle);
1343                 if (!ep)
1344                         return -EINVAL;
1345
1346                 transport->ep_disconnect(ep);
1347                 break;
1348         }
1349         return rc;
1350 }
1351
1352 static int
1353 iscsi_tgt_dscvr(struct iscsi_transport *transport,
1354                 struct iscsi_uevent *ev)
1355 {
1356         struct Scsi_Host *shost;
1357         struct sockaddr *dst_addr;
1358         int err;
1359
1360         if (!transport->tgt_dscvr)
1361                 return -EINVAL;
1362
1363         shost = scsi_host_lookup(ev->u.tgt_dscvr.host_no);
1364         if (!shost) {
1365                 printk(KERN_ERR "target discovery could not find host no %u\n",
1366                        ev->u.tgt_dscvr.host_no);
1367                 return -ENODEV;
1368         }
1369
1370
1371         dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1372         err = transport->tgt_dscvr(shost, ev->u.tgt_dscvr.type,
1373                                    ev->u.tgt_dscvr.enable, dst_addr);
1374         scsi_host_put(shost);
1375         return err;
1376 }
1377
1378 static int
1379 iscsi_set_host_param(struct iscsi_transport *transport,
1380                      struct iscsi_uevent *ev)
1381 {
1382         char *data = (char*)ev + sizeof(*ev);
1383         struct Scsi_Host *shost;
1384         int err;
1385
1386         if (!transport->set_host_param)
1387                 return -ENOSYS;
1388
1389         shost = scsi_host_lookup(ev->u.set_host_param.host_no);
1390         if (!shost) {
1391                 printk(KERN_ERR "set_host_param could not find host no %u\n",
1392                        ev->u.set_host_param.host_no);
1393                 return -ENODEV;
1394         }
1395
1396         err = transport->set_host_param(shost, ev->u.set_host_param.param,
1397                                         data, ev->u.set_host_param.len);
1398         scsi_host_put(shost);
1399         return err;
1400 }
1401
1402 static int
1403 iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
1404 {
1405         int err = 0;
1406         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1407         struct iscsi_transport *transport = NULL;
1408         struct iscsi_internal *priv;
1409         struct iscsi_cls_session *session;
1410         struct iscsi_cls_conn *conn;
1411         struct iscsi_endpoint *ep = NULL;
1412
1413         priv = iscsi_if_transport_lookup(iscsi_ptr(ev->transport_handle));
1414         if (!priv)
1415                 return -EINVAL;
1416         transport = priv->iscsi_transport;
1417
1418         if (!try_module_get(transport->owner))
1419                 return -EINVAL;
1420
1421         priv->daemon_pid = NETLINK_CREDS(skb)->pid;
1422
1423         switch (nlh->nlmsg_type) {
1424         case ISCSI_UEVENT_CREATE_SESSION:
1425                 err = iscsi_if_create_session(priv, ep, ev,
1426                                               ev->u.c_session.initial_cmdsn,
1427                                               ev->u.c_session.cmds_max,
1428                                               ev->u.c_session.queue_depth);
1429                 break;
1430         case ISCSI_UEVENT_CREATE_BOUND_SESSION:
1431                 ep = iscsi_lookup_endpoint(ev->u.c_bound_session.ep_handle);
1432                 if (!ep) {
1433                         err = -EINVAL;
1434                         break;
1435                 }
1436
1437                 err = iscsi_if_create_session(priv, ep, ev,
1438                                         ev->u.c_bound_session.initial_cmdsn,
1439                                         ev->u.c_bound_session.cmds_max,
1440                                         ev->u.c_bound_session.queue_depth);
1441                 break;
1442         case ISCSI_UEVENT_DESTROY_SESSION:
1443                 session = iscsi_session_lookup(ev->u.d_session.sid);
1444                 if (session)
1445                         transport->destroy_session(session);
1446                 else
1447                         err = -EINVAL;
1448                 break;
1449         case ISCSI_UEVENT_UNBIND_SESSION:
1450                 session = iscsi_session_lookup(ev->u.d_session.sid);
1451                 if (session)
1452                         iscsi_unbind_session(session);
1453                 else
1454                         err = -EINVAL;
1455                 break;
1456         case ISCSI_UEVENT_CREATE_CONN:
1457                 err = iscsi_if_create_conn(transport, ev);
1458                 break;
1459         case ISCSI_UEVENT_DESTROY_CONN:
1460                 err = iscsi_if_destroy_conn(transport, ev);
1461                 break;
1462         case ISCSI_UEVENT_BIND_CONN:
1463                 session = iscsi_session_lookup(ev->u.b_conn.sid);
1464                 conn = iscsi_conn_lookup(ev->u.b_conn.sid, ev->u.b_conn.cid);
1465
1466                 if (session && conn)
1467                         ev->r.retcode = transport->bind_conn(session, conn,
1468                                         ev->u.b_conn.transport_eph,
1469                                         ev->u.b_conn.is_leading);
1470                 else
1471                         err = -EINVAL;
1472                 break;
1473         case ISCSI_UEVENT_SET_PARAM:
1474                 err = iscsi_set_param(transport, ev);
1475                 break;
1476         case ISCSI_UEVENT_START_CONN:
1477                 conn = iscsi_conn_lookup(ev->u.start_conn.sid, ev->u.start_conn.cid);
1478                 if (conn)
1479                         ev->r.retcode = transport->start_conn(conn);
1480                 else
1481                         err = -EINVAL;
1482                 break;
1483         case ISCSI_UEVENT_STOP_CONN:
1484                 conn = iscsi_conn_lookup(ev->u.stop_conn.sid, ev->u.stop_conn.cid);
1485                 if (conn)
1486                         transport->stop_conn(conn, ev->u.stop_conn.flag);
1487                 else
1488                         err = -EINVAL;
1489                 break;
1490         case ISCSI_UEVENT_SEND_PDU:
1491                 conn = iscsi_conn_lookup(ev->u.send_pdu.sid, ev->u.send_pdu.cid);
1492                 if (conn)
1493                         ev->r.retcode = transport->send_pdu(conn,
1494                                 (struct iscsi_hdr*)((char*)ev + sizeof(*ev)),
1495                                 (char*)ev + sizeof(*ev) + ev->u.send_pdu.hdr_size,
1496                                 ev->u.send_pdu.data_size);
1497                 else
1498                         err = -EINVAL;
1499                 break;
1500         case ISCSI_UEVENT_GET_STATS:
1501                 err = iscsi_if_get_stats(transport, nlh);
1502                 break;
1503         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1504         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1505         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1506                 err = iscsi_if_transport_ep(transport, ev, nlh->nlmsg_type);
1507                 break;
1508         case ISCSI_UEVENT_TGT_DSCVR:
1509                 err = iscsi_tgt_dscvr(transport, ev);
1510                 break;
1511         case ISCSI_UEVENT_SET_HOST_PARAM:
1512                 err = iscsi_set_host_param(transport, ev);
1513                 break;
1514         default:
1515                 err = -ENOSYS;
1516                 break;
1517         }
1518
1519         module_put(transport->owner);
1520         return err;
1521 }
1522
1523 /*
1524  * Get message from skb.  Each message is processed by iscsi_if_recv_msg.
1525  * Malformed skbs with wrong lengths or invalid creds are not processed.
1526  */
1527 static void
1528 iscsi_if_rx(struct sk_buff *skb)
1529 {
1530         mutex_lock(&rx_queue_mutex);
1531         while (skb->len >= NLMSG_SPACE(0)) {
1532                 int err;
1533                 uint32_t rlen;
1534                 struct nlmsghdr *nlh;
1535                 struct iscsi_uevent *ev;
1536
1537                 nlh = nlmsg_hdr(skb);
1538                 if (nlh->nlmsg_len < sizeof(*nlh) ||
1539                     skb->len < nlh->nlmsg_len) {
1540                         break;
1541                 }
1542
1543                 ev = NLMSG_DATA(nlh);
1544                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1545                 if (rlen > skb->len)
1546                         rlen = skb->len;
1547
1548                 err = iscsi_if_recv_msg(skb, nlh);
1549                 if (err) {
1550                         ev->type = ISCSI_KEVENT_IF_ERROR;
1551                         ev->iferror = err;
1552                 }
1553                 do {
1554                         /*
1555                          * special case for GET_STATS:
1556                          * on success - sending reply and stats from
1557                          * inside of if_recv_msg(),
1558                          * on error - fall through.
1559                          */
1560                         if (ev->type == ISCSI_UEVENT_GET_STATS && !err)
1561                                 break;
1562                         err = iscsi_if_send_reply(
1563                                 NETLINK_CREDS(skb)->pid, nlh->nlmsg_seq,
1564                                 nlh->nlmsg_type, 0, 0, ev, sizeof(*ev));
1565                 } while (err < 0 && err != -ECONNREFUSED);
1566                 skb_pull(skb, rlen);
1567         }
1568         mutex_unlock(&rx_queue_mutex);
1569 }
1570
1571 #define ISCSI_CLASS_ATTR(_prefix,_name,_mode,_show,_store)              \
1572 struct device_attribute dev_attr_##_prefix##_##_name =  \
1573         __ATTR(_name,_mode,_show,_store)
1574
1575 /*
1576  * iSCSI connection attrs
1577  */
1578 #define iscsi_conn_attr_show(param)                                     \
1579 static ssize_t                                                          \
1580 show_conn_param_##param(struct device *dev,                             \
1581                         struct device_attribute *attr, char *buf)       \
1582 {                                                                       \
1583         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev->parent);   \
1584         struct iscsi_transport *t = conn->transport;                    \
1585         return t->get_conn_param(conn, param, buf);                     \
1586 }
1587
1588 #define iscsi_conn_attr(field, param)                                   \
1589         iscsi_conn_attr_show(param)                                     \
1590 static ISCSI_CLASS_ATTR(conn, field, S_IRUGO, show_conn_param_##param,  \
1591                         NULL);
1592
1593 iscsi_conn_attr(max_recv_dlength, ISCSI_PARAM_MAX_RECV_DLENGTH);
1594 iscsi_conn_attr(max_xmit_dlength, ISCSI_PARAM_MAX_XMIT_DLENGTH);
1595 iscsi_conn_attr(header_digest, ISCSI_PARAM_HDRDGST_EN);
1596 iscsi_conn_attr(data_digest, ISCSI_PARAM_DATADGST_EN);
1597 iscsi_conn_attr(ifmarker, ISCSI_PARAM_IFMARKER_EN);
1598 iscsi_conn_attr(ofmarker, ISCSI_PARAM_OFMARKER_EN);
1599 iscsi_conn_attr(persistent_port, ISCSI_PARAM_PERSISTENT_PORT);
1600 iscsi_conn_attr(port, ISCSI_PARAM_CONN_PORT);
1601 iscsi_conn_attr(exp_statsn, ISCSI_PARAM_EXP_STATSN);
1602 iscsi_conn_attr(persistent_address, ISCSI_PARAM_PERSISTENT_ADDRESS);
1603 iscsi_conn_attr(address, ISCSI_PARAM_CONN_ADDRESS);
1604 iscsi_conn_attr(ping_tmo, ISCSI_PARAM_PING_TMO);
1605 iscsi_conn_attr(recv_tmo, ISCSI_PARAM_RECV_TMO);
1606
1607 /*
1608  * iSCSI session attrs
1609  */
1610 #define iscsi_session_attr_show(param, perm)                            \
1611 static ssize_t                                                          \
1612 show_session_param_##param(struct device *dev,                          \
1613                            struct device_attribute *attr, char *buf)    \
1614 {                                                                       \
1615         struct iscsi_cls_session *session =                             \
1616                 iscsi_dev_to_session(dev->parent);                      \
1617         struct iscsi_transport *t = session->transport;                 \
1618                                                                         \
1619         if (perm && !capable(CAP_SYS_ADMIN))                            \
1620                 return -EACCES;                                         \
1621         return t->get_session_param(session, param, buf);               \
1622 }
1623
1624 #define iscsi_session_attr(field, param, perm)                          \
1625         iscsi_session_attr_show(param, perm)                            \
1626 static ISCSI_CLASS_ATTR(sess, field, S_IRUGO, show_session_param_##param, \
1627                         NULL);
1628
1629 iscsi_session_attr(targetname, ISCSI_PARAM_TARGET_NAME, 0);
1630 iscsi_session_attr(initial_r2t, ISCSI_PARAM_INITIAL_R2T_EN, 0);
1631 iscsi_session_attr(max_outstanding_r2t, ISCSI_PARAM_MAX_R2T, 0);
1632 iscsi_session_attr(immediate_data, ISCSI_PARAM_IMM_DATA_EN, 0);
1633 iscsi_session_attr(first_burst_len, ISCSI_PARAM_FIRST_BURST, 0);
1634 iscsi_session_attr(max_burst_len, ISCSI_PARAM_MAX_BURST, 0);
1635 iscsi_session_attr(data_pdu_in_order, ISCSI_PARAM_PDU_INORDER_EN, 0);
1636 iscsi_session_attr(data_seq_in_order, ISCSI_PARAM_DATASEQ_INORDER_EN, 0);
1637 iscsi_session_attr(erl, ISCSI_PARAM_ERL, 0);
1638 iscsi_session_attr(tpgt, ISCSI_PARAM_TPGT, 0);
1639 iscsi_session_attr(username, ISCSI_PARAM_USERNAME, 1);
1640 iscsi_session_attr(username_in, ISCSI_PARAM_USERNAME_IN, 1);
1641 iscsi_session_attr(password, ISCSI_PARAM_PASSWORD, 1);
1642 iscsi_session_attr(password_in, ISCSI_PARAM_PASSWORD_IN, 1);
1643 iscsi_session_attr(fast_abort, ISCSI_PARAM_FAST_ABORT, 0);
1644 iscsi_session_attr(abort_tmo, ISCSI_PARAM_ABORT_TMO, 0);
1645 iscsi_session_attr(lu_reset_tmo, ISCSI_PARAM_LU_RESET_TMO, 0);
1646 iscsi_session_attr(ifacename, ISCSI_PARAM_IFACE_NAME, 0);
1647 iscsi_session_attr(initiatorname, ISCSI_PARAM_INITIATOR_NAME, 0)
1648
1649 static ssize_t
1650 show_priv_session_state(struct device *dev, struct device_attribute *attr,
1651                         char *buf)
1652 {
1653         struct iscsi_cls_session *session = iscsi_dev_to_session(dev->parent);
1654         return sprintf(buf, "%s\n", iscsi_session_state_name(session->state));
1655 }
1656 static ISCSI_CLASS_ATTR(priv_sess, state, S_IRUGO, show_priv_session_state,
1657                         NULL);
1658
1659 #define iscsi_priv_session_attr_show(field, format)                     \
1660 static ssize_t                                                          \
1661 show_priv_session_##field(struct device *dev,                           \
1662                           struct device_attribute *attr, char *buf)     \
1663 {                                                                       \
1664         struct iscsi_cls_session *session =                             \
1665                         iscsi_dev_to_session(dev->parent);              \
1666         return sprintf(buf, format"\n", session->field);                \
1667 }
1668
1669 #define iscsi_priv_session_attr(field, format)                          \
1670         iscsi_priv_session_attr_show(field, format)                     \
1671 static ISCSI_CLASS_ATTR(priv_sess, field, S_IRUGO, show_priv_session_##field, \
1672                         NULL)
1673 iscsi_priv_session_attr(recovery_tmo, "%d");
1674
1675 /*
1676  * iSCSI host attrs
1677  */
1678 #define iscsi_host_attr_show(param)                                     \
1679 static ssize_t                                                          \
1680 show_host_param_##param(struct device *dev,                             \
1681                         struct device_attribute *attr, char *buf)       \
1682 {                                                                       \
1683         struct Scsi_Host *shost = transport_class_to_shost(dev);        \
1684         struct iscsi_internal *priv = to_iscsi_internal(shost->transportt); \
1685         return priv->iscsi_transport->get_host_param(shost, param, buf); \
1686 }
1687
1688 #define iscsi_host_attr(field, param)                                   \
1689         iscsi_host_attr_show(param)                                     \
1690 static ISCSI_CLASS_ATTR(host, field, S_IRUGO, show_host_param_##param,  \
1691                         NULL);
1692
1693 iscsi_host_attr(netdev, ISCSI_HOST_PARAM_NETDEV_NAME);
1694 iscsi_host_attr(hwaddress, ISCSI_HOST_PARAM_HWADDRESS);
1695 iscsi_host_attr(ipaddress, ISCSI_HOST_PARAM_IPADDRESS);
1696 iscsi_host_attr(initiatorname, ISCSI_HOST_PARAM_INITIATOR_NAME);
1697
1698 #define SETUP_PRIV_SESSION_RD_ATTR(field)                               \
1699 do {                                                                    \
1700         priv->session_attrs[count] = &dev_attr_priv_sess_##field; \
1701         count++;                                                        \
1702 } while (0)
1703
1704
1705 #define SETUP_SESSION_RD_ATTR(field, param_flag)                        \
1706 do {                                                                    \
1707         if (tt->param_mask & param_flag) {                              \
1708                 priv->session_attrs[count] = &dev_attr_sess_##field; \
1709                 count++;                                                \
1710         }                                                               \
1711 } while (0)
1712
1713 #define SETUP_CONN_RD_ATTR(field, param_flag)                           \
1714 do {                                                                    \
1715         if (tt->param_mask & param_flag) {                              \
1716                 priv->conn_attrs[count] = &dev_attr_conn_##field; \
1717                 count++;                                                \
1718         }                                                               \
1719 } while (0)
1720
1721 #define SETUP_HOST_RD_ATTR(field, param_flag)                           \
1722 do {                                                                    \
1723         if (tt->host_param_mask & param_flag) {                         \
1724                 priv->host_attrs[count] = &dev_attr_host_##field; \
1725                 count++;                                                \
1726         }                                                               \
1727 } while (0)
1728
1729 static int iscsi_session_match(struct attribute_container *cont,
1730                            struct device *dev)
1731 {
1732         struct iscsi_cls_session *session;
1733         struct Scsi_Host *shost;
1734         struct iscsi_internal *priv;
1735
1736         if (!iscsi_is_session_dev(dev))
1737                 return 0;
1738
1739         session = iscsi_dev_to_session(dev);
1740         shost = iscsi_session_to_shost(session);
1741         if (!shost->transportt)
1742                 return 0;
1743
1744         priv = to_iscsi_internal(shost->transportt);
1745         if (priv->session_cont.ac.class != &iscsi_session_class.class)
1746                 return 0;
1747
1748         return &priv->session_cont.ac == cont;
1749 }
1750
1751 static int iscsi_conn_match(struct attribute_container *cont,
1752                            struct device *dev)
1753 {
1754         struct iscsi_cls_session *session;
1755         struct iscsi_cls_conn *conn;
1756         struct Scsi_Host *shost;
1757         struct iscsi_internal *priv;
1758
1759         if (!iscsi_is_conn_dev(dev))
1760                 return 0;
1761
1762         conn = iscsi_dev_to_conn(dev);
1763         session = iscsi_dev_to_session(conn->dev.parent);
1764         shost = iscsi_session_to_shost(session);
1765
1766         if (!shost->transportt)
1767                 return 0;
1768
1769         priv = to_iscsi_internal(shost->transportt);
1770         if (priv->conn_cont.ac.class != &iscsi_connection_class.class)
1771                 return 0;
1772
1773         return &priv->conn_cont.ac == cont;
1774 }
1775
1776 static int iscsi_host_match(struct attribute_container *cont,
1777                             struct device *dev)
1778 {
1779         struct Scsi_Host *shost;
1780         struct iscsi_internal *priv;
1781
1782         if (!scsi_is_host_device(dev))
1783                 return 0;
1784
1785         shost = dev_to_shost(dev);
1786         if (!shost->transportt  ||
1787             shost->transportt->host_attrs.ac.class != &iscsi_host_class.class)
1788                 return 0;
1789
1790         priv = to_iscsi_internal(shost->transportt);
1791         return &priv->t.host_attrs.ac == cont;
1792 }
1793
1794 struct scsi_transport_template *
1795 iscsi_register_transport(struct iscsi_transport *tt)
1796 {
1797         struct iscsi_internal *priv;
1798         unsigned long flags;
1799         int count = 0, err;
1800
1801         BUG_ON(!tt);
1802
1803         priv = iscsi_if_transport_lookup(tt);
1804         if (priv)
1805                 return NULL;
1806
1807         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1808         if (!priv)
1809                 return NULL;
1810         INIT_LIST_HEAD(&priv->list);
1811         priv->daemon_pid = -1;
1812         priv->iscsi_transport = tt;
1813         priv->t.user_scan = iscsi_user_scan;
1814         if (!(tt->caps & CAP_DATA_PATH_OFFLOAD))
1815                 priv->t.create_work_queue = 1;
1816
1817         priv->dev.class = &iscsi_transport_class;
1818         snprintf(priv->dev.bus_id, BUS_ID_SIZE, "%s", tt->name);
1819         err = device_register(&priv->dev);
1820         if (err)
1821                 goto free_priv;
1822
1823         err = sysfs_create_group(&priv->dev.kobj, &iscsi_transport_group);
1824         if (err)
1825                 goto unregister_dev;
1826
1827         /* host parameters */
1828         priv->t.host_attrs.ac.attrs = &priv->host_attrs[0];
1829         priv->t.host_attrs.ac.class = &iscsi_host_class.class;
1830         priv->t.host_attrs.ac.match = iscsi_host_match;
1831         priv->t.host_size = sizeof(struct iscsi_cls_host);
1832         transport_container_register(&priv->t.host_attrs);
1833
1834         SETUP_HOST_RD_ATTR(netdev, ISCSI_HOST_NETDEV_NAME);
1835         SETUP_HOST_RD_ATTR(ipaddress, ISCSI_HOST_IPADDRESS);
1836         SETUP_HOST_RD_ATTR(hwaddress, ISCSI_HOST_HWADDRESS);
1837         SETUP_HOST_RD_ATTR(initiatorname, ISCSI_HOST_INITIATOR_NAME);
1838         BUG_ON(count > ISCSI_HOST_ATTRS);
1839         priv->host_attrs[count] = NULL;
1840         count = 0;
1841
1842         /* connection parameters */
1843         priv->conn_cont.ac.attrs = &priv->conn_attrs[0];
1844         priv->conn_cont.ac.class = &iscsi_connection_class.class;
1845         priv->conn_cont.ac.match = iscsi_conn_match;
1846         transport_container_register(&priv->conn_cont);
1847
1848         SETUP_CONN_RD_ATTR(max_recv_dlength, ISCSI_MAX_RECV_DLENGTH);
1849         SETUP_CONN_RD_ATTR(max_xmit_dlength, ISCSI_MAX_XMIT_DLENGTH);
1850         SETUP_CONN_RD_ATTR(header_digest, ISCSI_HDRDGST_EN);
1851         SETUP_CONN_RD_ATTR(data_digest, ISCSI_DATADGST_EN);
1852         SETUP_CONN_RD_ATTR(ifmarker, ISCSI_IFMARKER_EN);
1853         SETUP_CONN_RD_ATTR(ofmarker, ISCSI_OFMARKER_EN);
1854         SETUP_CONN_RD_ATTR(address, ISCSI_CONN_ADDRESS);
1855         SETUP_CONN_RD_ATTR(port, ISCSI_CONN_PORT);
1856         SETUP_CONN_RD_ATTR(exp_statsn, ISCSI_EXP_STATSN);
1857         SETUP_CONN_RD_ATTR(persistent_address, ISCSI_PERSISTENT_ADDRESS);
1858         SETUP_CONN_RD_ATTR(persistent_port, ISCSI_PERSISTENT_PORT);
1859         SETUP_CONN_RD_ATTR(ping_tmo, ISCSI_PING_TMO);
1860         SETUP_CONN_RD_ATTR(recv_tmo, ISCSI_RECV_TMO);
1861
1862         BUG_ON(count > ISCSI_CONN_ATTRS);
1863         priv->conn_attrs[count] = NULL;
1864         count = 0;
1865
1866         /* session parameters */
1867         priv->session_cont.ac.attrs = &priv->session_attrs[0];
1868         priv->session_cont.ac.class = &iscsi_session_class.class;
1869         priv->session_cont.ac.match = iscsi_session_match;
1870         transport_container_register(&priv->session_cont);
1871
1872         SETUP_SESSION_RD_ATTR(initial_r2t, ISCSI_INITIAL_R2T_EN);
1873         SETUP_SESSION_RD_ATTR(max_outstanding_r2t, ISCSI_MAX_R2T);
1874         SETUP_SESSION_RD_ATTR(immediate_data, ISCSI_IMM_DATA_EN);
1875         SETUP_SESSION_RD_ATTR(first_burst_len, ISCSI_FIRST_BURST);
1876         SETUP_SESSION_RD_ATTR(max_burst_len, ISCSI_MAX_BURST);
1877         SETUP_SESSION_RD_ATTR(data_pdu_in_order, ISCSI_PDU_INORDER_EN);
1878         SETUP_SESSION_RD_ATTR(data_seq_in_order, ISCSI_DATASEQ_INORDER_EN);
1879         SETUP_SESSION_RD_ATTR(erl, ISCSI_ERL);
1880         SETUP_SESSION_RD_ATTR(targetname, ISCSI_TARGET_NAME);
1881         SETUP_SESSION_RD_ATTR(tpgt, ISCSI_TPGT);
1882         SETUP_SESSION_RD_ATTR(password, ISCSI_USERNAME);
1883         SETUP_SESSION_RD_ATTR(password_in, ISCSI_USERNAME_IN);
1884         SETUP_SESSION_RD_ATTR(username, ISCSI_PASSWORD);
1885         SETUP_SESSION_RD_ATTR(username_in, ISCSI_PASSWORD_IN);
1886         SETUP_SESSION_RD_ATTR(fast_abort, ISCSI_FAST_ABORT);
1887         SETUP_SESSION_RD_ATTR(abort_tmo, ISCSI_ABORT_TMO);
1888         SETUP_SESSION_RD_ATTR(lu_reset_tmo,ISCSI_LU_RESET_TMO);
1889         SETUP_SESSION_RD_ATTR(ifacename, ISCSI_IFACE_NAME);
1890         SETUP_SESSION_RD_ATTR(initiatorname, ISCSI_INITIATOR_NAME);
1891         SETUP_PRIV_SESSION_RD_ATTR(recovery_tmo);
1892         SETUP_PRIV_SESSION_RD_ATTR(state);
1893
1894         BUG_ON(count > ISCSI_SESSION_ATTRS);
1895         priv->session_attrs[count] = NULL;
1896
1897         spin_lock_irqsave(&iscsi_transport_lock, flags);
1898         list_add(&priv->list, &iscsi_transports);
1899         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1900
1901         printk(KERN_NOTICE "iscsi: registered transport (%s)\n", tt->name);
1902         return &priv->t;
1903
1904 unregister_dev:
1905         device_unregister(&priv->dev);
1906         return NULL;
1907 free_priv:
1908         kfree(priv);
1909         return NULL;
1910 }
1911 EXPORT_SYMBOL_GPL(iscsi_register_transport);
1912
1913 int iscsi_unregister_transport(struct iscsi_transport *tt)
1914 {
1915         struct iscsi_internal *priv;
1916         unsigned long flags;
1917
1918         BUG_ON(!tt);
1919
1920         mutex_lock(&rx_queue_mutex);
1921
1922         priv = iscsi_if_transport_lookup(tt);
1923         BUG_ON (!priv);
1924
1925         spin_lock_irqsave(&iscsi_transport_lock, flags);
1926         list_del(&priv->list);
1927         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1928
1929         transport_container_unregister(&priv->conn_cont);
1930         transport_container_unregister(&priv->session_cont);
1931         transport_container_unregister(&priv->t.host_attrs);
1932
1933         sysfs_remove_group(&priv->dev.kobj, &iscsi_transport_group);
1934         device_unregister(&priv->dev);
1935         mutex_unlock(&rx_queue_mutex);
1936
1937         return 0;
1938 }
1939 EXPORT_SYMBOL_GPL(iscsi_unregister_transport);
1940
1941 static __init int iscsi_transport_init(void)
1942 {
1943         int err;
1944
1945         printk(KERN_INFO "Loading iSCSI transport class v%s.\n",
1946                 ISCSI_TRANSPORT_VERSION);
1947
1948         atomic_set(&iscsi_session_nr, 0);
1949
1950         err = class_register(&iscsi_transport_class);
1951         if (err)
1952                 return err;
1953
1954         err = class_register(&iscsi_endpoint_class);
1955         if (err)
1956                 goto unregister_transport_class;
1957
1958         err = transport_class_register(&iscsi_host_class);
1959         if (err)
1960                 goto unregister_endpoint_class;
1961
1962         err = transport_class_register(&iscsi_connection_class);
1963         if (err)
1964                 goto unregister_host_class;
1965
1966         err = transport_class_register(&iscsi_session_class);
1967         if (err)
1968                 goto unregister_conn_class;
1969
1970         nls = netlink_kernel_create(&init_net, NETLINK_ISCSI, 1, iscsi_if_rx,
1971                                     NULL, THIS_MODULE);
1972         if (!nls) {
1973                 err = -ENOBUFS;
1974                 goto unregister_session_class;
1975         }
1976
1977         iscsi_eh_timer_workq = create_singlethread_workqueue("iscsi_eh");
1978         if (!iscsi_eh_timer_workq)
1979                 goto release_nls;
1980
1981         return 0;
1982
1983 release_nls:
1984         netlink_kernel_release(nls);
1985 unregister_session_class:
1986         transport_class_unregister(&iscsi_session_class);
1987 unregister_conn_class:
1988         transport_class_unregister(&iscsi_connection_class);
1989 unregister_host_class:
1990         transport_class_unregister(&iscsi_host_class);
1991 unregister_endpoint_class:
1992         class_unregister(&iscsi_endpoint_class);
1993 unregister_transport_class:
1994         class_unregister(&iscsi_transport_class);
1995         return err;
1996 }
1997
1998 static void __exit iscsi_transport_exit(void)
1999 {
2000         destroy_workqueue(iscsi_eh_timer_workq);
2001         netlink_kernel_release(nls);
2002         transport_class_unregister(&iscsi_connection_class);
2003         transport_class_unregister(&iscsi_session_class);
2004         transport_class_unregister(&iscsi_host_class);
2005         class_unregister(&iscsi_endpoint_class);
2006         class_unregister(&iscsi_transport_class);
2007 }
2008
2009 module_init(iscsi_transport_init);
2010 module_exit(iscsi_transport_exit);
2011
2012 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
2013               "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
2014               "Alex Aizman <itn780@yahoo.com>");
2015 MODULE_DESCRIPTION("iSCSI Transport Interface");
2016 MODULE_LICENSE("GPL");
2017 MODULE_VERSION(ISCSI_TRANSPORT_VERSION);