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         struct scsi_transport_template t;
  41         struct iscsi_transport *iscsi_transport;
  42         struct list_head list;
  43         struct device dev;
  44
  45         struct device_attribute *host_attrs[ISCSI_HOST_ATTRS + 1];
  46         struct transport_container conn_cont;
  47         struct device_attribute *conn_attrs[ISCSI_CONN_ATTRS + 1];
  48         struct transport_container session_cont;
  49         struct device_attribute *session_attrs[ISCSI_SESSION_ATTRS + 1];
  50 };
  51
  52 static atomic_t iscsi_session_nr; /* sysfs session id for next new session */
  53 static struct workqueue_struct *iscsi_eh_timer_workq;
  54
  55 /*
  56  * list of registered transports and lock that must
  57  * be held while accessing list. The iscsi_transport_lock must
  58  * be acquired after the rx_queue_mutex.
  59  */
  60 static LIST_HEAD(iscsi_transports);
  61 static DEFINE_SPINLOCK(iscsi_transport_lock);
  62
  63 #define to_iscsi_internal(tmpl) \
  64         container_of(tmpl, struct iscsi_internal, t)
  65
  66 #define dev_to_iscsi_internal(_dev) \
  67         container_of(_dev, struct iscsi_internal, dev)
  68
  69 static void iscsi_transport_release(struct device *dev)
  70 {
  71         struct iscsi_internal *priv = dev_to_iscsi_internal(dev);
  72         kfree(priv);
  73 }
  74
  75 /*
  76  * iscsi_transport_class represents the iscsi_transports that are
  77  * registered.
  78  */
  79 static struct class iscsi_transport_class = {
  80         .name = "iscsi_transport",
  81         .dev_release = iscsi_transport_release,
  82 };
  83
  84 static ssize_t
  85 show_transport_handle(struct device *dev, struct device_attribute *attr,
  86                       char *buf)
  87 {
  88         struct iscsi_internal *priv = dev_to_iscsi_internal(dev);
  89         return sprintf(buf, "%llu\n", (unsigned long long)iscsi_handle(priv->iscsi_transport));
  90 }
  91 static DEVICE_ATTR(handle, S_IRUGO, show_transport_handle, NULL);
  92
  93 #define show_transport_attr(name, format)                               \
  94 static ssize_t                                                          \
  95 show_transport_##name(struct device *dev,                               \
  96                       struct device_attribute *attr,char *buf)          \
  97 {                                                                       \
  98         struct iscsi_internal *priv = dev_to_iscsi_internal(dev);       \
  99         return sprintf(buf, format"\n", priv->iscsi_transport->name);   \
 100 }                                                                       \
 101 static DEVICE_ATTR(name, S_IRUGO, show_transport_##name, NULL);
 102
 103 show_transport_attr(caps, "0x%x");
 104
 105 static struct attribute *iscsi_transport_attrs[] = {
 106         &dev_attr_handle.attr,
 107         &dev_attr_caps.attr,
 108         NULL,
 109 };
 110
 111 static struct attribute_group iscsi_transport_group = {
 112         .attrs = iscsi_transport_attrs,
 113 };
 114
 115 /*
 116  * iSCSI endpoint attrs
 117  */
 118 #define iscsi_dev_to_endpoint(_dev) \
 119         container_of(_dev, struct iscsi_endpoint, dev)
 120
 121 #define ISCSI_ATTR(_prefix,_name,_mode,_show,_store)    \
 122 struct device_attribute dev_attr_##_prefix##_##_name =  \
 123         __ATTR(_name,_mode,_show,_store)
 124
 125 static void iscsi_endpoint_release(struct device *dev)
 126 {
 127         struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
 128         kfree(ep);
 129 }
 130
 131 static struct class iscsi_endpoint_class = {
 132         .name = "iscsi_endpoint",
 133         .dev_release = iscsi_endpoint_release,
 134 };
 135
 136 static ssize_t
 137 show_ep_handle(struct device *dev, struct device_attribute *attr, char *buf)
 138 {
 139         struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
 140         return sprintf(buf, "%llu\n", (unsigned long long) ep->id);
 141 }
 142 static ISCSI_ATTR(ep, handle, S_IRUGO, show_ep_handle, NULL);
 143
 144 static struct attribute *iscsi_endpoint_attrs[] = {
 145         &dev_attr_ep_handle.attr,
 146         NULL,
 147 };
 148
 149 static struct attribute_group iscsi_endpoint_group = {
 150         .attrs = iscsi_endpoint_attrs,
 151 };
 152
 153 #define ISCSI_MAX_EPID -1
 154
 155 static int iscsi_match_epid(struct device *dev, void *data)
 156 {
 157         struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
 158         uint64_t *epid = (uint64_t *) data;
 159
 160         return *epid == ep->id;
 161 }
 162
 163 struct iscsi_endpoint *
 164 iscsi_create_endpoint(int dd_size)
 165 {
 166         struct device *dev;
 167         struct iscsi_endpoint *ep;
 168         uint64_t id;
 169         int err;
 170
 171         for (id = 1; id < ISCSI_MAX_EPID; id++) {
 172                 dev = class_find_device(&iscsi_endpoint_class, NULL, &id,
 173                                         iscsi_match_epid);
 174                 if (!dev)
 175                         break;
 176         }
 177         if (id == ISCSI_MAX_EPID) {
 178                 printk(KERN_ERR "Too many connections. Max supported %u\n",
 179                        ISCSI_MAX_EPID - 1);
 180                 return NULL;
 181         }
 182
 183         ep = kzalloc(sizeof(*ep) + dd_size, GFP_KERNEL);
 184         if (!ep)
 185                 return NULL;
 186
 187         ep->id = id;
 188         ep->dev.class = &iscsi_endpoint_class;
 189         dev_set_name(&ep->dev, "ep-%llu", (unsigned long long) id);
 190         err = device_register(&ep->dev);
 191         if (err)
 192                 goto free_ep;
 193
 194         err = sysfs_create_group(&ep->dev.kobj, &iscsi_endpoint_group);
 195         if (err)
 196                 goto unregister_dev;
 197
 198         if (dd_size)
 199                 ep->dd_data = &ep[1];
 200         return ep;
 201
 202 unregister_dev:
 203         device_unregister(&ep->dev);
 204         return NULL;
 205
 206 free_ep:
 207         kfree(ep);
 208         return NULL;
 209 }
 210 EXPORT_SYMBOL_GPL(iscsi_create_endpoint);
 211
 212 void iscsi_destroy_endpoint(struct iscsi_endpoint *ep)
 213 {
 214         sysfs_remove_group(&ep->dev.kobj, &iscsi_endpoint_group);
 215         device_unregister(&ep->dev);
 216 }
 217 EXPORT_SYMBOL_GPL(iscsi_destroy_endpoint);
 218
 219 struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle)
 220 {
 221         struct iscsi_endpoint *ep;
 222         struct device *dev;
 223
 224         dev = class_find_device(&iscsi_endpoint_class, NULL, &handle,
 225                                 iscsi_match_epid);
 226         if (!dev)
 227                 return NULL;
 228
 229         ep = iscsi_dev_to_endpoint(dev);
 230         /*
 231          * we can drop this now because the interface will prevent
 232          * removals and lookups from racing.
 233          */
 234         put_device(dev);
 235         return ep;
 236 }
 237 EXPORT_SYMBOL_GPL(iscsi_lookup_endpoint);
 238
 239 static int iscsi_setup_host(struct transport_container *tc, struct device *dev,
 240                             struct device *cdev)
 241 {
 242         struct Scsi_Host *shost = dev_to_shost(dev);
 243         struct iscsi_cls_host *ihost = shost->shost_data;
 244
 245         memset(ihost, 0, sizeof(*ihost));
 246         atomic_set(&ihost->nr_scans, 0);
 247         mutex_init(&ihost->mutex);
 248         return 0;
 249 }
 250
 251 static DECLARE_TRANSPORT_CLASS(iscsi_host_class,
 252                                "iscsi_host",
 253                                iscsi_setup_host,
 254                                NULL,
 255                                NULL);
 256
 257 static DECLARE_TRANSPORT_CLASS(iscsi_session_class,
 258                                "iscsi_session",
 259                                NULL,
 260                                NULL,
 261                                NULL);
 262
 263 static DECLARE_TRANSPORT_CLASS(iscsi_connection_class,
 264                                "iscsi_connection",
 265                                NULL,
 266                                NULL,
 267                                NULL);
 268
 269 static struct sock *nls;
 270 static DEFINE_MUTEX(rx_queue_mutex);
 271
 272 static LIST_HEAD(sesslist);
 273 static DEFINE_SPINLOCK(sesslock);
 274 static LIST_HEAD(connlist);
 275 static DEFINE_SPINLOCK(connlock);
 276
 277 static uint32_t iscsi_conn_get_sid(struct iscsi_cls_conn *conn)
 278 {
 279         struct iscsi_cls_session *sess = iscsi_dev_to_session(conn->dev.parent);
 280         return sess->sid;
 281 }
 282
 283 /*
 284  * Returns the matching session to a given sid
 285  */
 286 static struct iscsi_cls_session *iscsi_session_lookup(uint32_t sid)
 287 {
 288         unsigned long flags;
 289         struct iscsi_cls_session *sess;
 290
 291         spin_lock_irqsave(&sesslock, flags);
 292         list_for_each_entry(sess, &sesslist, sess_list) {
 293                 if (sess->sid == sid) {
 294                         spin_unlock_irqrestore(&sesslock, flags);
 295                         return sess;
 296                 }
 297         }
 298         spin_unlock_irqrestore(&sesslock, flags);
 299         return NULL;
 300 }
 301
 302 /*
 303  * Returns the matching connection to a given sid / cid tuple
 304  */
 305 static struct iscsi_cls_conn *iscsi_conn_lookup(uint32_t sid, uint32_t cid)
 306 {
 307         unsigned long flags;
 308         struct iscsi_cls_conn *conn;
 309
 310         spin_lock_irqsave(&connlock, flags);
 311         list_for_each_entry(conn, &connlist, conn_list) {
 312                 if ((conn->cid == cid) && (iscsi_conn_get_sid(conn) == sid)) {
 313                         spin_unlock_irqrestore(&connlock, flags);
 314                         return conn;
 315                 }
 316         }
 317         spin_unlock_irqrestore(&connlock, flags);
 318         return NULL;
 319 }
 320
 321 /*
 322  * The following functions can be used by LLDs that allocate
 323  * their own scsi_hosts or by software iscsi LLDs
 324  */
 325 static struct {
 326         int value;
 327         char *name;
 328 } iscsi_session_state_names[] = {
 329         { ISCSI_SESSION_LOGGED_IN,      "LOGGED_IN" },
 330         { ISCSI_SESSION_FAILED,         "FAILED" },
 331         { ISCSI_SESSION_FREE,           "FREE" },
 332 };
 333
 334 static const char *iscsi_session_state_name(int state)
 335 {
 336         int i;
 337         char *name = NULL;
 338
 339         for (i = 0; i < ARRAY_SIZE(iscsi_session_state_names); i++) {
 340                 if (iscsi_session_state_names[i].value == state) {
 341                         name = iscsi_session_state_names[i].name;
 342                         break;
 343                 }
 344         }
 345         return name;
 346 }
 347
 348 int iscsi_session_chkready(struct iscsi_cls_session *session)
 349 {
 350         unsigned long flags;
 351         int err;
 352
 353         spin_lock_irqsave(&session->lock, flags);
 354         switch (session->state) {
 355         case ISCSI_SESSION_LOGGED_IN:
 356                 err = 0;
 357                 break;
 358         case ISCSI_SESSION_FAILED:
 359                 err = DID_IMM_RETRY << 16;
 360                 break;
 361         case ISCSI_SESSION_FREE:
 362                 err = DID_TRANSPORT_FAILFAST << 16;
 363                 break;
 364         default:
 365                 err = DID_NO_CONNECT << 16;
 366                 break;
 367         }
 368         spin_unlock_irqrestore(&session->lock, flags);
 369         return err;
 370 }
 371 EXPORT_SYMBOL_GPL(iscsi_session_chkready);
 372
 373 static void iscsi_session_release(struct device *dev)
 374 {
 375         struct iscsi_cls_session *session = iscsi_dev_to_session(dev);
 376         struct Scsi_Host *shost;
 377
 378         shost = iscsi_session_to_shost(session);
 379         scsi_host_put(shost);
 380         kfree(session);
 381 }
 382
 383 static int iscsi_is_session_dev(const struct device *dev)
 384 {
 385         return dev->release == iscsi_session_release;
 386 }
 387
 388 static int iscsi_iter_session_fn(struct device *dev, void *data)
 389 {
 390         void (* fn) (struct iscsi_cls_session *) = data;
 391
 392         if (!iscsi_is_session_dev(dev))
 393                 return 0;
 394         fn(iscsi_dev_to_session(dev));
 395         return 0;
 396 }
 397
 398 void iscsi_host_for_each_session(struct Scsi_Host *shost,
 399                                  void (*fn)(struct iscsi_cls_session *))
 400 {
 401         device_for_each_child(&shost->shost_gendev, fn,
 402                               iscsi_iter_session_fn);
 403 }
 404 EXPORT_SYMBOL_GPL(iscsi_host_for_each_session);
 405
 406 /**
 407  * iscsi_scan_finished - helper to report when running scans are done
 408  * @shost: scsi host
 409  * @time: scan run time
 410  *
 411  * This function can be used by drives like qla4xxx to report to the scsi
 412  * layer when the scans it kicked off at module load time are done.
 413  */
 414 int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time)
 415 {
 416         struct iscsi_cls_host *ihost = shost->shost_data;
 417         /*
 418          * qla4xxx will have kicked off some session unblocks before calling
 419          * scsi_scan_host, so just wait for them to complete.
 420          */
 421         return !atomic_read(&ihost->nr_scans);
 422 }
 423 EXPORT_SYMBOL_GPL(iscsi_scan_finished);
 424
 425 struct iscsi_scan_data {
 426         unsigned int channel;
 427         unsigned int id;
 428         unsigned int lun;
 429 };
 430
 431 static int iscsi_user_scan_session(struct device *dev, void *data)
 432 {
 433         struct iscsi_scan_data *scan_data = data;
 434         struct iscsi_cls_session *session;
 435         struct Scsi_Host *shost;
 436         struct iscsi_cls_host *ihost;
 437         unsigned long flags;
 438         unsigned int id;
 439
 440         if (!iscsi_is_session_dev(dev))
 441                 return 0;
 442
 443         session = iscsi_dev_to_session(dev);
 444         shost = iscsi_session_to_shost(session);
 445         ihost = shost->shost_data;
 446
 447         mutex_lock(&ihost->mutex);
 448         spin_lock_irqsave(&session->lock, flags);
 449         if (session->state != ISCSI_SESSION_LOGGED_IN) {
 450                 spin_unlock_irqrestore(&session->lock, flags);
 451                 mutex_unlock(&ihost->mutex);
 452                 return 0;
 453         }
 454         id = session->target_id;
 455         spin_unlock_irqrestore(&session->lock, flags);
 456
 457         if (id != ISCSI_MAX_TARGET) {
 458                 if ((scan_data->channel == SCAN_WILD_CARD ||
 459                      scan_data->channel == 0) &&
 460                     (scan_data->id == SCAN_WILD_CARD ||
 461                      scan_data->id == id))
 462                         scsi_scan_target(&session->dev, 0, id,
 463                                          scan_data->lun, 1);
 464         }
 465         mutex_unlock(&ihost->mutex);
 466         return 0;
 467 }
 468
 469 static int iscsi_user_scan(struct Scsi_Host *shost, uint channel,
 470                            uint id, uint lun)
 471 {
 472         struct iscsi_scan_data scan_data;
 473
 474         scan_data.channel = channel;
 475         scan_data.id = id;
 476         scan_data.lun = lun;
 477
 478         return device_for_each_child(&shost->shost_gendev, &scan_data,
 479                                      iscsi_user_scan_session);
 480 }
 481
 482 static void iscsi_scan_session(struct work_struct *work)
 483 {
 484         struct iscsi_cls_session *session =
 485                         container_of(work, struct iscsi_cls_session, scan_work);
 486         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 487         struct iscsi_cls_host *ihost = shost->shost_data;
 488         struct iscsi_scan_data scan_data;
 489
 490         scan_data.channel = 0;
 491         scan_data.id = SCAN_WILD_CARD;
 492         scan_data.lun = SCAN_WILD_CARD;
 493
 494         iscsi_user_scan_session(&session->dev, &scan_data);
 495         atomic_dec(&ihost->nr_scans);
 496 }
 497
 498 static void session_recovery_timedout(struct work_struct *work)
 499 {
 500         struct iscsi_cls_session *session =
 501                 container_of(work, struct iscsi_cls_session,
 502                              recovery_work.work);
 503         unsigned long flags;
 504
 505         iscsi_cls_session_printk(KERN_INFO, session,
 506                                  "session recovery timed out after %d secs\n",
 507                                  session->recovery_tmo);
 508
 509         spin_lock_irqsave(&session->lock, flags);
 510         switch (session->state) {
 511         case ISCSI_SESSION_FAILED:
 512                 session->state = ISCSI_SESSION_FREE;
 513                 break;
 514         case ISCSI_SESSION_LOGGED_IN:
 515         case ISCSI_SESSION_FREE:
 516                 /* we raced with the unblock's flush */
 517                 spin_unlock_irqrestore(&session->lock, flags);
 518                 return;
 519         }
 520         spin_unlock_irqrestore(&session->lock, flags);
 521
 522         if (session->transport->session_recovery_timedout)
 523                 session->transport->session_recovery_timedout(session);
 524
 525         scsi_target_unblock(&session->dev);
 526 }
 527
 528 static void __iscsi_unblock_session(struct work_struct *work)
 529 {
 530         struct iscsi_cls_session *session =
 531                         container_of(work, struct iscsi_cls_session,
 532                                      unblock_work);
 533         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 534         struct iscsi_cls_host *ihost = shost->shost_data;
 535         unsigned long flags;
 536
 537         /*
 538          * The recovery and unblock work get run from the same workqueue,
 539          * so try to cancel it if it was going to run after this unblock.
 540          */
 541         cancel_delayed_work(&session->recovery_work);
 542         spin_lock_irqsave(&session->lock, flags);
 543         session->state = ISCSI_SESSION_LOGGED_IN;
 544         spin_unlock_irqrestore(&session->lock, flags);
 545         /* start IO */
 546         scsi_target_unblock(&session->dev);
 547         /*
 548          * Only do kernel scanning if the driver is properly hooked into
 549          * the async scanning code (drivers like iscsi_tcp do login and
 550          * scanning from userspace).
 551          */
 552         if (shost->hostt->scan_finished) {
 553                 if (scsi_queue_work(shost, &session->scan_work))
 554                         atomic_inc(&ihost->nr_scans);
 555         }
 556 }
 557
 558 /**
 559  * iscsi_unblock_session - set a session as logged in and start IO.
 560  * @session: iscsi session
 561  *
 562  * Mark a session as ready to accept IO.
 563  */
 564 void iscsi_unblock_session(struct iscsi_cls_session *session)
 565 {
 566         queue_work(iscsi_eh_timer_workq, &session->unblock_work);
 567         /*
 568          * make sure all the events have completed before tell the driver
 569          * it is safe
 570          */
 571         flush_workqueue(iscsi_eh_timer_workq);
 572 }
 573 EXPORT_SYMBOL_GPL(iscsi_unblock_session);
 574
 575 static void __iscsi_block_session(struct work_struct *work)
 576 {
 577         struct iscsi_cls_session *session =
 578                         container_of(work, struct iscsi_cls_session,
 579                                      block_work);
 580         unsigned long flags;
 581
 582         spin_lock_irqsave(&session->lock, flags);
 583         session->state = ISCSI_SESSION_FAILED;
 584         spin_unlock_irqrestore(&session->lock, flags);
 585         scsi_target_block(&session->dev);
 586         queue_delayed_work(iscsi_eh_timer_workq, &session->recovery_work,
 587                            session->recovery_tmo * HZ);
 588 }
 589
 590 void iscsi_block_session(struct iscsi_cls_session *session)
 591 {
 592         queue_work(iscsi_eh_timer_workq, &session->block_work);
 593 }
 594 EXPORT_SYMBOL_GPL(iscsi_block_session);
 595
 596 static void __iscsi_unbind_session(struct work_struct *work)
 597 {
 598         struct iscsi_cls_session *session =
 599                         container_of(work, struct iscsi_cls_session,
 600                                      unbind_work);
 601         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 602         struct iscsi_cls_host *ihost = shost->shost_data;
 603         unsigned long flags;
 604
 605         /* Prevent new scans and make sure scanning is not in progress */
 606         mutex_lock(&ihost->mutex);
 607         spin_lock_irqsave(&session->lock, flags);
 608         if (session->target_id == ISCSI_MAX_TARGET) {
 609                 spin_unlock_irqrestore(&session->lock, flags);
 610                 mutex_unlock(&ihost->mutex);
 611                 return;
 612         }
 613         session->target_id = ISCSI_MAX_TARGET;
 614         spin_unlock_irqrestore(&session->lock, flags);
 615         mutex_unlock(&ihost->mutex);
 616
 617         scsi_remove_target(&session->dev);
 618         iscsi_session_event(session, ISCSI_KEVENT_UNBIND_SESSION);
 619 }
 620
 621 struct iscsi_cls_session *
 622 iscsi_alloc_session(struct Scsi_Host *shost, struct iscsi_transport *transport,
 623                     int dd_size)
 624 {
 625         struct iscsi_cls_session *session;
 626
 627         session = kzalloc(sizeof(*session) + dd_size,
 628                           GFP_KERNEL);
 629         if (!session)
 630                 return NULL;
 631
 632         session->transport = transport;
 633         session->recovery_tmo = 120;
 634         session->state = ISCSI_SESSION_FREE;
 635         INIT_DELAYED_WORK(&session->recovery_work, session_recovery_timedout);
 636         INIT_LIST_HEAD(&session->sess_list);
 637         INIT_WORK(&session->unblock_work, __iscsi_unblock_session);
 638         INIT_WORK(&session->block_work, __iscsi_block_session);
 639         INIT_WORK(&session->unbind_work, __iscsi_unbind_session);
 640         INIT_WORK(&session->scan_work, iscsi_scan_session);
 641         spin_lock_init(&session->lock);
 642
 643         /* this is released in the dev's release function */
 644         scsi_host_get(shost);
 645         session->dev.parent = &shost->shost_gendev;
 646         session->dev.release = iscsi_session_release;
 647         device_initialize(&session->dev);
 648         if (dd_size)
 649                 session->dd_data = &session[1];
 650         return session;
 651 }
 652 EXPORT_SYMBOL_GPL(iscsi_alloc_session);
 653
 654 static int iscsi_get_next_target_id(struct device *dev, void *data)
 655 {
 656         struct iscsi_cls_session *session;
 657         unsigned long flags;
 658         int err = 0;
 659
 660         if (!iscsi_is_session_dev(dev))
 661                 return 0;
 662
 663         session = iscsi_dev_to_session(dev);
 664         spin_lock_irqsave(&session->lock, flags);
 665         if (*((unsigned int *) data) == session->target_id)
 666                 err = -EEXIST;
 667         spin_unlock_irqrestore(&session->lock, flags);
 668         return err;
 669 }
 670
 671 int iscsi_add_session(struct iscsi_cls_session *session, unsigned int target_id)
 672 {
 673         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 674         struct iscsi_cls_host *ihost;
 675         unsigned long flags;
 676         unsigned int id = target_id;
 677         int err;
 678
 679         ihost = shost->shost_data;
 680         session->sid = atomic_add_return(1, &iscsi_session_nr);
 681
 682         if (id == ISCSI_MAX_TARGET) {
 683                 for (id = 0; id < ISCSI_MAX_TARGET; id++) {
 684                         err = device_for_each_child(&shost->shost_gendev, &id,
 685                                                     iscsi_get_next_target_id);
 686                         if (!err)
 687                                 break;
 688                 }
 689
 690                 if (id == ISCSI_MAX_TARGET) {
 691                         iscsi_cls_session_printk(KERN_ERR, session,
 692                                                  "Too many iscsi targets. Max "
 693                                                  "number of targets is %d.\n",
 694                                                  ISCSI_MAX_TARGET - 1);
 695                         err = -EOVERFLOW;
 696                         goto release_host;
 697                 }
 698         }
 699         session->target_id = id;
 700
 701         dev_set_name(&session->dev, "session%u", session->sid);
 702         err = device_add(&session->dev);
 703         if (err) {
 704                 iscsi_cls_session_printk(KERN_ERR, session,
 705                                          "could not register session's dev\n");
 706                 goto release_host;
 707         }
 708         transport_register_device(&session->dev);
 709
 710         spin_lock_irqsave(&sesslock, flags);
 711         list_add(&session->sess_list, &sesslist);
 712         spin_unlock_irqrestore(&sesslock, flags);
 713
 714         iscsi_session_event(session, ISCSI_KEVENT_CREATE_SESSION);
 715         return 0;
 716
 717 release_host:
 718         scsi_host_put(shost);
 719         return err;
 720 }
 721 EXPORT_SYMBOL_GPL(iscsi_add_session);
 722
 723 /**
 724  * iscsi_create_session - create iscsi class session
 725  * @shost: scsi host
 726  * @transport: iscsi transport
 727  * @dd_size: private driver data size
 728  * @target_id: which target
 729  *
 730  * This can be called from a LLD or iscsi_transport.
 731  */
 732 struct iscsi_cls_session *
 733 iscsi_create_session(struct Scsi_Host *shost, struct iscsi_transport *transport,
 734                      int dd_size, unsigned int target_id)
 735 {
 736         struct iscsi_cls_session *session;
 737
 738         session = iscsi_alloc_session(shost, transport, dd_size);
 739         if (!session)
 740                 return NULL;
 741
 742         if (iscsi_add_session(session, target_id)) {
 743                 iscsi_free_session(session);
 744                 return NULL;
 745         }
 746         return session;
 747 }
 748 EXPORT_SYMBOL_GPL(iscsi_create_session);
 749
 750 static void iscsi_conn_release(struct device *dev)
 751 {
 752         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev);
 753         struct device *parent = conn->dev.parent;
 754
 755         kfree(conn);
 756         put_device(parent);
 757 }
 758
 759 static int iscsi_is_conn_dev(const struct device *dev)
 760 {
 761         return dev->release == iscsi_conn_release;
 762 }
 763
 764 static int iscsi_iter_destroy_conn_fn(struct device *dev, void *data)
 765 {
 766         if (!iscsi_is_conn_dev(dev))
 767                 return 0;
 768         return iscsi_destroy_conn(iscsi_dev_to_conn(dev));
 769 }
 770
 771 void iscsi_remove_session(struct iscsi_cls_session *session)
 772 {
 773         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 774         unsigned long flags;
 775         int err;
 776
 777         spin_lock_irqsave(&sesslock, flags);
 778         list_del(&session->sess_list);
 779         spin_unlock_irqrestore(&sesslock, flags);
 780
 781         /* make sure there are no blocks/unblocks queued */
 782         flush_workqueue(iscsi_eh_timer_workq);
 783         /* make sure the timedout callout is not running */
 784         if (!cancel_delayed_work(&session->recovery_work))
 785                 flush_workqueue(iscsi_eh_timer_workq);
 786         /*
 787          * If we are blocked let commands flow again. The lld or iscsi
 788          * layer should set up the queuecommand to fail commands.
 789          * We assume that LLD will not be calling block/unblock while
 790          * removing the session.
 791          */
 792         spin_lock_irqsave(&session->lock, flags);
 793         session->state = ISCSI_SESSION_FREE;
 794         spin_unlock_irqrestore(&session->lock, flags);
 795
 796         scsi_target_unblock(&session->dev);
 797         /* flush running scans then delete devices */
 798         scsi_flush_work(shost);
 799         __iscsi_unbind_session(&session->unbind_work);
 800
 801         /* hw iscsi may not have removed all connections from session */
 802         err = device_for_each_child(&session->dev, NULL,
 803                                     iscsi_iter_destroy_conn_fn);
 804         if (err)
 805                 iscsi_cls_session_printk(KERN_ERR, session,
 806                                          "Could not delete all connections "
 807                                          "for session. Error %d.\n", err);
 808
 809         transport_unregister_device(&session->dev);
 810         device_del(&session->dev);
 811 }
 812 EXPORT_SYMBOL_GPL(iscsi_remove_session);
 813
 814 void iscsi_free_session(struct iscsi_cls_session *session)
 815 {
 816         iscsi_session_event(session, ISCSI_KEVENT_DESTROY_SESSION);
 817         put_device(&session->dev);
 818 }
 819 EXPORT_SYMBOL_GPL(iscsi_free_session);
 820
 821 /**
 822  * iscsi_destroy_session - destroy iscsi session
 823  * @session: iscsi_session
 824  *
 825  * Can be called by a LLD or iscsi_transport. There must not be
 826  * any running connections.
 827  */
 828 int iscsi_destroy_session(struct iscsi_cls_session *session)
 829 {
 830         iscsi_remove_session(session);
 831         iscsi_free_session(session);
 832         return 0;
 833 }
 834 EXPORT_SYMBOL_GPL(iscsi_destroy_session);
 835
 836 /**
 837  * iscsi_create_conn - create iscsi class connection
 838  * @session: iscsi cls session
 839  * @dd_size: private driver data size
 840  * @cid: connection id
 841  *
 842  * This can be called from a LLD or iscsi_transport. The connection
 843  * is child of the session so cid must be unique for all connections
 844  * on the session.
 845  *
 846  * Since we do not support MCS, cid will normally be zero. In some cases
 847  * for software iscsi we could be trying to preallocate a connection struct
 848  * in which case there could be two connection structs and cid would be
 849  * non-zero.
 850  */
 851 struct iscsi_cls_conn *
 852 iscsi_create_conn(struct iscsi_cls_session *session, int dd_size, uint32_t cid)
 853 {
 854         struct iscsi_transport *transport = session->transport;
 855         struct iscsi_cls_conn *conn;
 856         unsigned long flags;
 857         int err;
 858
 859         conn = kzalloc(sizeof(*conn) + dd_size, GFP_KERNEL);
 860         if (!conn)
 861                 return NULL;
 862         if (dd_size)
 863                 conn->dd_data = &conn[1];
 864
 865         INIT_LIST_HEAD(&conn->conn_list);
 866         conn->transport = transport;
 867         conn->cid = cid;
 868
 869         /* this is released in the dev's release function */
 870         if (!get_device(&session->dev))
 871                 goto free_conn;
 872
 873         dev_set_name(&conn->dev, "connection%d:%u", session->sid, cid);
 874         conn->dev.parent = &session->dev;
 875         conn->dev.release = iscsi_conn_release;
 876         err = device_register(&conn->dev);
 877         if (err) {
 878                 iscsi_cls_session_printk(KERN_ERR, session, "could not "
 879                                          "register connection's dev\n");
 880                 goto release_parent_ref;
 881         }
 882         transport_register_device(&conn->dev);
 883
 884         spin_lock_irqsave(&connlock, flags);
 885         list_add(&conn->conn_list, &connlist);
 886         conn->active = 1;
 887         spin_unlock_irqrestore(&connlock, flags);
 888         return conn;
 889
 890 release_parent_ref:
 891         put_device(&session->dev);
 892 free_conn:
 893         kfree(conn);
 894         return NULL;
 895 }
 896
 897 EXPORT_SYMBOL_GPL(iscsi_create_conn);
 898
 899 /**
 900  * iscsi_destroy_conn - destroy iscsi class connection
 901  * @conn: iscsi cls session
 902  *
 903  * This can be called from a LLD or iscsi_transport.
 904  */
 905 int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
 906 {
 907         unsigned long flags;
 908
 909         spin_lock_irqsave(&connlock, flags);
 910         conn->active = 0;
 911         list_del(&conn->conn_list);
 912         spin_unlock_irqrestore(&connlock, flags);
 913
 914         transport_unregister_device(&conn->dev);
 915         device_unregister(&conn->dev);
 916         return 0;
 917 }
 918 EXPORT_SYMBOL_GPL(iscsi_destroy_conn);
 919
 920 /*
 921  * iscsi interface functions
 922  */
 923 static struct iscsi_internal *
 924 iscsi_if_transport_lookup(struct iscsi_transport *tt)
 925 {
 926         struct iscsi_internal *priv;
 927         unsigned long flags;
 928
 929         spin_lock_irqsave(&iscsi_transport_lock, flags);
 930         list_for_each_entry(priv, &iscsi_transports, list) {
 931                 if (tt == priv->iscsi_transport) {
 932                         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 933                         return priv;
 934                 }
 935         }
 936         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 937         return NULL;
 938 }
 939
 940 static int
 941 iscsi_multicast_skb(struct sk_buff *skb, uint32_t group, gfp_t gfp)
 942 {
 943         return nlmsg_multicast(nls, skb, 0, group, gfp);
 944 }
 945
 946 int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
 947                    char *data, uint32_t data_size)
 948 {
 949         struct nlmsghdr *nlh;
 950         struct sk_buff *skb;
 951         struct iscsi_uevent *ev;
 952         char *pdu;
 953         struct iscsi_internal *priv;
 954         int len = NLMSG_SPACE(sizeof(*ev) + sizeof(struct iscsi_hdr) +
 955                               data_size);
 956
 957         priv = iscsi_if_transport_lookup(conn->transport);
 958         if (!priv)
 959                 return -EINVAL;
 960
 961         skb = alloc_skb(len, GFP_ATOMIC);
 962         if (!skb) {
 963                 iscsi_conn_error_event(conn, ISCSI_ERR_CONN_FAILED);
 964                 iscsi_cls_conn_printk(KERN_ERR, conn, "can not deliver "
 965                                       "control PDU: OOM\n");
 966                 return -ENOMEM;
 967         }
 968
 969         nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
 970         ev = NLMSG_DATA(nlh);
 971         memset(ev, 0, sizeof(*ev));
 972         ev->transport_handle = iscsi_handle(conn->transport);
 973         ev->type = ISCSI_KEVENT_RECV_PDU;
 974         ev->r.recv_req.cid = conn->cid;
 975         ev->r.recv_req.sid = iscsi_conn_get_sid(conn);
 976         pdu = (char*)ev + sizeof(*ev);
 977         memcpy(pdu, hdr, sizeof(struct iscsi_hdr));
 978         memcpy(pdu + sizeof(struct iscsi_hdr), data, data_size);
 979
 980         return iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_ATOMIC);
 981 }
 982 EXPORT_SYMBOL_GPL(iscsi_recv_pdu);
 983
 984 int iscsi_offload_mesg(struct Scsi_Host *shost,
 985                        struct iscsi_transport *transport, uint32_t type,
 986                        char *data, uint16_t data_size)
 987 {
 988         struct nlmsghdr *nlh;
 989         struct sk_buff *skb;
 990         struct iscsi_uevent *ev;
 991         int len = NLMSG_SPACE(sizeof(*ev) + data_size);
 992
 993         skb = alloc_skb(len, GFP_ATOMIC);
 994         if (!skb) {
 995                 printk(KERN_ERR "can not deliver iscsi offload message:OOM\n");
 996                 return -ENOMEM;
 997         }
 998
 999         nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1000         ev = NLMSG_DATA(nlh);
1001         memset(ev, 0, sizeof(*ev));
1002         ev->type = type;
1003         ev->transport_handle = iscsi_handle(transport);
1004         switch (type) {
1005         case ISCSI_KEVENT_PATH_REQ:
1006                 ev->r.req_path.host_no = shost->host_no;
1007                 break;
1008         case ISCSI_KEVENT_IF_DOWN:
1009                 ev->r.notify_if_down.host_no = shost->host_no;
1010                 break;
1011         }
1012
1013         memcpy((char *)ev + sizeof(*ev), data, data_size);
1014
1015         return iscsi_multicast_skb(skb, ISCSI_NL_GRP_UIP, GFP_ATOMIC);
1016 }
1017 EXPORT_SYMBOL_GPL(iscsi_offload_mesg);
1018
1019 void iscsi_conn_error_event(struct iscsi_cls_conn *conn, enum iscsi_err error)
1020 {
1021         struct nlmsghdr *nlh;
1022         struct sk_buff  *skb;
1023         struct iscsi_uevent *ev;
1024         struct iscsi_internal *priv;
1025         int len = NLMSG_SPACE(sizeof(*ev));
1026
1027         priv = iscsi_if_transport_lookup(conn->transport);
1028         if (!priv)
1029                 return;
1030
1031         skb = alloc_skb(len, GFP_ATOMIC);
1032         if (!skb) {
1033                 iscsi_cls_conn_printk(KERN_ERR, conn, "gracefully ignored "
1034                                       "conn error (%d)\n", error);
1035                 return;
1036         }
1037
1038         nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1039         ev = NLMSG_DATA(nlh);
1040         ev->transport_handle = iscsi_handle(conn->transport);
1041         ev->type = ISCSI_KEVENT_CONN_ERROR;
1042         ev->r.connerror.error = error;
1043         ev->r.connerror.cid = conn->cid;
1044         ev->r.connerror.sid = iscsi_conn_get_sid(conn);
1045
1046         iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_ATOMIC);
1047
1048         iscsi_cls_conn_printk(KERN_INFO, conn, "detected conn error (%d)\n",
1049                               error);
1050 }
1051 EXPORT_SYMBOL_GPL(iscsi_conn_error_event);
1052
1053 static int
1054 iscsi_if_send_reply(uint32_t group, int seq, int type, int done, int multi,
1055                     void *payload, int size)
1056 {
1057         struct sk_buff  *skb;
1058         struct nlmsghdr *nlh;
1059         int len = NLMSG_SPACE(size);
1060         int flags = multi ? NLM_F_MULTI : 0;
1061         int t = done ? NLMSG_DONE : type;
1062
1063         skb = alloc_skb(len, GFP_ATOMIC);
1064         if (!skb) {
1065                 printk(KERN_ERR "Could not allocate skb to send reply.\n");
1066                 return -ENOMEM;
1067         }
1068
1069         nlh = __nlmsg_put(skb, 0, 0, t, (len - sizeof(*nlh)), 0);
1070         nlh->nlmsg_flags = flags;
1071         memcpy(NLMSG_DATA(nlh), payload, size);
1072         return iscsi_multicast_skb(skb, group, GFP_ATOMIC);
1073 }
1074
1075 static int
1076 iscsi_if_get_stats(struct iscsi_transport *transport, struct nlmsghdr *nlh)
1077 {
1078         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1079         struct iscsi_stats *stats;
1080         struct sk_buff *skbstat;
1081         struct iscsi_cls_conn *conn;
1082         struct nlmsghdr *nlhstat;
1083         struct iscsi_uevent *evstat;
1084         struct iscsi_internal *priv;
1085         int len = NLMSG_SPACE(sizeof(*ev) +
1086                               sizeof(struct iscsi_stats) +
1087                               sizeof(struct iscsi_stats_custom) *
1088                               ISCSI_STATS_CUSTOM_MAX);
1089         int err = 0;
1090
1091         priv = iscsi_if_transport_lookup(transport);
1092         if (!priv)
1093                 return -EINVAL;
1094
1095         conn = iscsi_conn_lookup(ev->u.get_stats.sid, ev->u.get_stats.cid);
1096         if (!conn)
1097                 return -EEXIST;
1098
1099         do {
1100                 int actual_size;
1101
1102                 skbstat = alloc_skb(len, GFP_ATOMIC);
1103                 if (!skbstat) {
1104                         iscsi_cls_conn_printk(KERN_ERR, conn, "can not "
1105                                               "deliver stats: OOM\n");
1106                         return -ENOMEM;
1107                 }
1108
1109                 nlhstat = __nlmsg_put(skbstat, 0, 0, 0,
1110                                       (len - sizeof(*nlhstat)), 0);
1111                 evstat = NLMSG_DATA(nlhstat);
1112                 memset(evstat, 0, sizeof(*evstat));
1113                 evstat->transport_handle = iscsi_handle(conn->transport);
1114                 evstat->type = nlh->nlmsg_type;
1115                 evstat->u.get_stats.cid =
1116                         ev->u.get_stats.cid;
1117                 evstat->u.get_stats.sid =
1118                         ev->u.get_stats.sid;
1119                 stats = (struct iscsi_stats *)
1120                         ((char*)evstat + sizeof(*evstat));
1121                 memset(stats, 0, sizeof(*stats));
1122
1123                 transport->get_stats(conn, stats);
1124                 actual_size = NLMSG_SPACE(sizeof(struct iscsi_uevent) +
1125                                           sizeof(struct iscsi_stats) +
1126                                           sizeof(struct iscsi_stats_custom) *
1127                                           stats->custom_length);
1128                 actual_size -= sizeof(*nlhstat);
1129                 actual_size = NLMSG_LENGTH(actual_size);
1130                 skb_trim(skbstat, NLMSG_ALIGN(actual_size));
1131                 nlhstat->nlmsg_len = actual_size;
1132
1133                 err = iscsi_multicast_skb(skbstat, ISCSI_NL_GRP_ISCSID,
1134                                           GFP_ATOMIC);
1135         } while (err < 0 && err != -ECONNREFUSED);
1136
1137         return err;
1138 }
1139
1140 /**
1141  * iscsi_session_event - send session destr. completion event
1142  * @session: iscsi class session
1143  * @event: type of event
1144  */
1145 int iscsi_session_event(struct iscsi_cls_session *session,
1146                         enum iscsi_uevent_e event)
1147 {
1148         struct iscsi_internal *priv;
1149         struct Scsi_Host *shost;
1150         struct iscsi_uevent *ev;
1151         struct sk_buff  *skb;
1152         struct nlmsghdr *nlh;
1153         int rc, len = NLMSG_SPACE(sizeof(*ev));
1154
1155         priv = iscsi_if_transport_lookup(session->transport);
1156         if (!priv)
1157                 return -EINVAL;
1158         shost = iscsi_session_to_shost(session);
1159
1160         skb = alloc_skb(len, GFP_KERNEL);
1161         if (!skb) {
1162                 iscsi_cls_session_printk(KERN_ERR, session,
1163                                          "Cannot notify userspace of session "
1164                                          "event %u\n", event);
1165                 return -ENOMEM;
1166         }
1167
1168         nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1169         ev = NLMSG_DATA(nlh);
1170         ev->transport_handle = iscsi_handle(session->transport);
1171
1172         ev->type = event;
1173         switch (event) {
1174         case ISCSI_KEVENT_DESTROY_SESSION:
1175                 ev->r.d_session.host_no = shost->host_no;
1176                 ev->r.d_session.sid = session->sid;
1177                 break;
1178         case ISCSI_KEVENT_CREATE_SESSION:
1179                 ev->r.c_session_ret.host_no = shost->host_no;
1180                 ev->r.c_session_ret.sid = session->sid;
1181                 break;
1182         case ISCSI_KEVENT_UNBIND_SESSION:
1183                 ev->r.unbind_session.host_no = shost->host_no;
1184                 ev->r.unbind_session.sid = session->sid;
1185                 break;
1186         default:
1187                 iscsi_cls_session_printk(KERN_ERR, session, "Invalid event "
1188                                          "%u.\n", event);
1189                 kfree_skb(skb);
1190                 return -EINVAL;
1191         }
1192
1193         /*
1194          * this will occur if the daemon is not up, so we just warn
1195          * the user and when the daemon is restarted it will handle it
1196          */
1197         rc = iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_KERNEL);
1198         if (rc == -ESRCH)
1199                 iscsi_cls_session_printk(KERN_ERR, session,
1200                                          "Cannot notify userspace of session "
1201                                          "event %u. Check iscsi daemon\n",
1202                                          event);
1203         return rc;
1204 }
1205 EXPORT_SYMBOL_GPL(iscsi_session_event);
1206
1207 static int
1208 iscsi_if_create_session(struct iscsi_internal *priv, struct iscsi_endpoint *ep,
1209                         struct iscsi_uevent *ev, uint32_t initial_cmdsn,
1210                         uint16_t cmds_max, uint16_t queue_depth)
1211 {
1212         struct iscsi_transport *transport = priv->iscsi_transport;
1213         struct iscsi_cls_session *session;
1214         struct Scsi_Host *shost;
1215
1216         session = transport->create_session(ep, cmds_max, queue_depth,
1217                                             initial_cmdsn);
1218         if (!session)
1219                 return -ENOMEM;
1220
1221         shost = iscsi_session_to_shost(session);
1222         ev->r.c_session_ret.host_no = shost->host_no;
1223         ev->r.c_session_ret.sid = session->sid;
1224         return 0;
1225 }
1226
1227 static int
1228 iscsi_if_create_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1229 {
1230         struct iscsi_cls_conn *conn;
1231         struct iscsi_cls_session *session;
1232
1233         session = iscsi_session_lookup(ev->u.c_conn.sid);
1234         if (!session) {
1235                 printk(KERN_ERR "iscsi: invalid session %d.\n",
1236                        ev->u.c_conn.sid);
1237                 return -EINVAL;
1238         }
1239
1240         conn = transport->create_conn(session, ev->u.c_conn.cid);
1241         if (!conn) {
1242                 iscsi_cls_session_printk(KERN_ERR, session,
1243                                          "couldn't create a new connection.");
1244                 return -ENOMEM;
1245         }
1246
1247         ev->r.c_conn_ret.sid = session->sid;
1248         ev->r.c_conn_ret.cid = conn->cid;
1249         return 0;
1250 }
1251
1252 static int
1253 iscsi_if_destroy_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1254 {
1255         struct iscsi_cls_conn *conn;
1256
1257         conn = iscsi_conn_lookup(ev->u.d_conn.sid, ev->u.d_conn.cid);
1258         if (!conn)
1259                 return -EINVAL;
1260
1261         if (transport->destroy_conn)
1262                 transport->destroy_conn(conn);
1263         return 0;
1264 }
1265
1266 static int
1267 iscsi_set_param(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1268 {
1269         char *data = (char*)ev + sizeof(*ev);
1270         struct iscsi_cls_conn *conn;
1271         struct iscsi_cls_session *session;
1272         int err = 0, value = 0;
1273
1274         session = iscsi_session_lookup(ev->u.set_param.sid);
1275         conn = iscsi_conn_lookup(ev->u.set_param.sid, ev->u.set_param.cid);
1276         if (!conn || !session)
1277                 return -EINVAL;
1278
1279         switch (ev->u.set_param.param) {
1280         case ISCSI_PARAM_SESS_RECOVERY_TMO:
1281                 sscanf(data, "%d", &value);
1282                 if (value != 0)
1283                         session->recovery_tmo = value;
1284                 break;
1285         default:
1286                 err = transport->set_param(conn, ev->u.set_param.param,
1287                                            data, ev->u.set_param.len);
1288         }
1289
1290         return err;
1291 }
1292
1293 static int iscsi_if_ep_connect(struct iscsi_transport *transport,
1294                                struct iscsi_uevent *ev, int msg_type)
1295 {
1296         struct iscsi_endpoint *ep;
1297         struct sockaddr *dst_addr;
1298         struct Scsi_Host *shost = NULL;
1299         int non_blocking, err = 0;
1300
1301         if (!transport->ep_connect)
1302                 return -EINVAL;
1303
1304         if (msg_type == ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST) {
1305                 shost = scsi_host_lookup(ev->u.ep_connect_through_host.host_no);
1306                 if (!shost) {
1307                         printk(KERN_ERR "ep connect failed. Could not find "
1308                                "host no %u\n",
1309                                ev->u.ep_connect_through_host.host_no);
1310                         return -ENODEV;
1311                 }
1312                 non_blocking = ev->u.ep_connect_through_host.non_blocking;
1313         } else
1314                 non_blocking = ev->u.ep_connect.non_blocking;
1315
1316         dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1317         ep = transport->ep_connect(shost, dst_addr, non_blocking);
1318         if (IS_ERR(ep)) {
1319                 err = PTR_ERR(ep);
1320                 goto release_host;
1321         }
1322
1323         ev->r.ep_connect_ret.handle = ep->id;
1324 release_host:
1325         if (shost)
1326                 scsi_host_put(shost);
1327         return err;
1328 }
1329
1330 static int
1331 iscsi_if_transport_ep(struct iscsi_transport *transport,
1332                       struct iscsi_uevent *ev, int msg_type)
1333 {
1334         struct iscsi_endpoint *ep;
1335         int rc = 0;
1336
1337         switch (msg_type) {
1338         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST:
1339         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1340                 rc = iscsi_if_ep_connect(transport, ev, msg_type);
1341                 break;
1342         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1343                 if (!transport->ep_poll)
1344                         return -EINVAL;
1345
1346                 ep = iscsi_lookup_endpoint(ev->u.ep_poll.ep_handle);
1347                 if (!ep)
1348                         return -EINVAL;
1349
1350                 ev->r.retcode = transport->ep_poll(ep,
1351                                                    ev->u.ep_poll.timeout_ms);
1352                 break;
1353         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1354                 if (!transport->ep_disconnect)
1355                         return -EINVAL;
1356
1357                 ep = iscsi_lookup_endpoint(ev->u.ep_disconnect.ep_handle);
1358                 if (!ep)
1359                         return -EINVAL;
1360
1361                 transport->ep_disconnect(ep);
1362                 break;
1363         }
1364         return rc;
1365 }
1366
1367 static int
1368 iscsi_tgt_dscvr(struct iscsi_transport *transport,
1369                 struct iscsi_uevent *ev)
1370 {
1371         struct Scsi_Host *shost;
1372         struct sockaddr *dst_addr;
1373         int err;
1374
1375         if (!transport->tgt_dscvr)
1376                 return -EINVAL;
1377
1378         shost = scsi_host_lookup(ev->u.tgt_dscvr.host_no);
1379         if (!shost) {
1380                 printk(KERN_ERR "target discovery could not find host no %u\n",
1381                        ev->u.tgt_dscvr.host_no);
1382                 return -ENODEV;
1383         }
1384
1385
1386         dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1387         err = transport->tgt_dscvr(shost, ev->u.tgt_dscvr.type,
1388                                    ev->u.tgt_dscvr.enable, dst_addr);
1389         scsi_host_put(shost);
1390         return err;
1391 }
1392
1393 static int
1394 iscsi_set_host_param(struct iscsi_transport *transport,
1395                      struct iscsi_uevent *ev)
1396 {
1397         char *data = (char*)ev + sizeof(*ev);
1398         struct Scsi_Host *shost;
1399         int err;
1400
1401         if (!transport->set_host_param)
1402                 return -ENOSYS;
1403
1404         shost = scsi_host_lookup(ev->u.set_host_param.host_no);
1405         if (!shost) {
1406                 printk(KERN_ERR "set_host_param could not find host no %u\n",
1407                        ev->u.set_host_param.host_no);
1408                 return -ENODEV;
1409         }
1410
1411         err = transport->set_host_param(shost, ev->u.set_host_param.param,
1412                                         data, ev->u.set_host_param.len);
1413         scsi_host_put(shost);
1414         return err;
1415 }
1416
1417 static int
1418 iscsi_set_path(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1419 {
1420         struct Scsi_Host *shost;
1421         struct iscsi_path *params;
1422         int err;
1423
1424         if (!transport->set_path)
1425                 return -ENOSYS;
1426
1427         shost = scsi_host_lookup(ev->u.set_path.host_no);
1428         if (!shost) {
1429                 printk(KERN_ERR "set path could not find host no %u\n",
1430                        ev->u.set_path.host_no);
1431                 return -ENODEV;
1432         }
1433
1434         params = (struct iscsi_path *)((char *)ev + sizeof(*ev));
1435         err = transport->set_path(shost, params);
1436
1437         scsi_host_put(shost);
1438         return err;
1439 }
1440
1441 static int
1442 iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, uint32_t *group)
1443 {
1444         int err = 0;
1445         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1446         struct iscsi_transport *transport = NULL;
1447         struct iscsi_internal *priv;
1448         struct iscsi_cls_session *session;
1449         struct iscsi_cls_conn *conn;
1450         struct iscsi_endpoint *ep = NULL;
1451
1452         if (nlh->nlmsg_type == ISCSI_UEVENT_PATH_UPDATE)
1453                 *group = ISCSI_NL_GRP_UIP;
1454         else
1455                 *group = ISCSI_NL_GRP_ISCSID;
1456
1457         priv = iscsi_if_transport_lookup(iscsi_ptr(ev->transport_handle));
1458         if (!priv)
1459                 return -EINVAL;
1460         transport = priv->iscsi_transport;
1461
1462         if (!try_module_get(transport->owner))
1463                 return -EINVAL;
1464
1465         switch (nlh->nlmsg_type) {
1466         case ISCSI_UEVENT_CREATE_SESSION:
1467                 err = iscsi_if_create_session(priv, ep, ev,
1468                                               ev->u.c_session.initial_cmdsn,
1469                                               ev->u.c_session.cmds_max,
1470                                               ev->u.c_session.queue_depth);
1471                 break;
1472         case ISCSI_UEVENT_CREATE_BOUND_SESSION:
1473                 ep = iscsi_lookup_endpoint(ev->u.c_bound_session.ep_handle);
1474                 if (!ep) {
1475                         err = -EINVAL;
1476                         break;
1477                 }
1478
1479                 err = iscsi_if_create_session(priv, ep, ev,
1480                                         ev->u.c_bound_session.initial_cmdsn,
1481                                         ev->u.c_bound_session.cmds_max,
1482                                         ev->u.c_bound_session.queue_depth);
1483                 break;
1484         case ISCSI_UEVENT_DESTROY_SESSION:
1485                 session = iscsi_session_lookup(ev->u.d_session.sid);
1486                 if (session)
1487                         transport->destroy_session(session);
1488                 else
1489                         err = -EINVAL;
1490                 break;
1491         case ISCSI_UEVENT_UNBIND_SESSION:
1492                 session = iscsi_session_lookup(ev->u.d_session.sid);
1493                 if (session)
1494                         scsi_queue_work(iscsi_session_to_shost(session),
1495                                         &session->unbind_work);
1496                 else
1497                         err = -EINVAL;
1498                 break;
1499         case ISCSI_UEVENT_CREATE_CONN:
1500                 err = iscsi_if_create_conn(transport, ev);
1501                 break;
1502         case ISCSI_UEVENT_DESTROY_CONN:
1503                 err = iscsi_if_destroy_conn(transport, ev);
1504                 break;
1505         case ISCSI_UEVENT_BIND_CONN:
1506                 session = iscsi_session_lookup(ev->u.b_conn.sid);
1507                 conn = iscsi_conn_lookup(ev->u.b_conn.sid, ev->u.b_conn.cid);
1508
1509                 if (session && conn)
1510                         ev->r.retcode = transport->bind_conn(session, conn,
1511                                         ev->u.b_conn.transport_eph,
1512                                         ev->u.b_conn.is_leading);
1513                 else
1514                         err = -EINVAL;
1515                 break;
1516         case ISCSI_UEVENT_SET_PARAM:
1517                 err = iscsi_set_param(transport, ev);
1518                 break;
1519         case ISCSI_UEVENT_START_CONN:
1520                 conn = iscsi_conn_lookup(ev->u.start_conn.sid, ev->u.start_conn.cid);
1521                 if (conn)
1522                         ev->r.retcode = transport->start_conn(conn);
1523                 else
1524                         err = -EINVAL;
1525                 break;
1526         case ISCSI_UEVENT_STOP_CONN:
1527                 conn = iscsi_conn_lookup(ev->u.stop_conn.sid, ev->u.stop_conn.cid);
1528                 if (conn)
1529                         transport->stop_conn(conn, ev->u.stop_conn.flag);
1530                 else
1531                         err = -EINVAL;
1532                 break;
1533         case ISCSI_UEVENT_SEND_PDU:
1534                 conn = iscsi_conn_lookup(ev->u.send_pdu.sid, ev->u.send_pdu.cid);
1535                 if (conn)
1536                         ev->r.retcode = transport->send_pdu(conn,
1537                                 (struct iscsi_hdr*)((char*)ev + sizeof(*ev)),
1538                                 (char*)ev + sizeof(*ev) + ev->u.send_pdu.hdr_size,
1539                                 ev->u.send_pdu.data_size);
1540                 else
1541                         err = -EINVAL;
1542                 break;
1543         case ISCSI_UEVENT_GET_STATS:
1544                 err = iscsi_if_get_stats(transport, nlh);
1545                 break;
1546         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1547         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1548         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1549         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST:
1550                 err = iscsi_if_transport_ep(transport, ev, nlh->nlmsg_type);
1551                 break;
1552         case ISCSI_UEVENT_TGT_DSCVR:
1553                 err = iscsi_tgt_dscvr(transport, ev);
1554                 break;
1555         case ISCSI_UEVENT_SET_HOST_PARAM:
1556                 err = iscsi_set_host_param(transport, ev);
1557                 break;
1558         case ISCSI_UEVENT_PATH_UPDATE:
1559                 err = iscsi_set_path(transport, ev);
1560                 break;
1561         default:
1562                 err = -ENOSYS;
1563                 break;
1564         }
1565
1566         module_put(transport->owner);
1567         return err;
1568 }
1569
1570 /*
1571  * Get message from skb.  Each message is processed by iscsi_if_recv_msg.
1572  * Malformed skbs with wrong lengths or invalid creds are not processed.
1573  */
1574 static void
1575 iscsi_if_rx(struct sk_buff *skb)
1576 {
1577         mutex_lock(&rx_queue_mutex);
1578         while (skb->len >= NLMSG_SPACE(0)) {
1579                 int err;
1580                 uint32_t rlen;
1581                 struct nlmsghdr *nlh;
1582                 struct iscsi_uevent *ev;
1583                 uint32_t group;
1584
1585                 nlh = nlmsg_hdr(skb);
1586                 if (nlh->nlmsg_len < sizeof(*nlh) ||
1587                     skb->len < nlh->nlmsg_len) {
1588                         break;
1589                 }
1590
1591                 ev = NLMSG_DATA(nlh);
1592                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1593                 if (rlen > skb->len)
1594                         rlen = skb->len;
1595
1596                 err = iscsi_if_recv_msg(skb, nlh, &group);
1597                 if (err) {
1598                         ev->type = ISCSI_KEVENT_IF_ERROR;
1599                         ev->iferror = err;
1600                 }
1601                 do {
1602                         /*
1603                          * special case for GET_STATS:
1604                          * on success - sending reply and stats from
1605                          * inside of if_recv_msg(),
1606                          * on error - fall through.
1607                          */
1608                         if (ev->type == ISCSI_UEVENT_GET_STATS && !err)
1609                                 break;
1610                         err = iscsi_if_send_reply(group, nlh->nlmsg_seq,
1611                                 nlh->nlmsg_type, 0, 0, ev, sizeof(*ev));
1612                 } while (err < 0 && err != -ECONNREFUSED);
1613                 skb_pull(skb, rlen);
1614         }
1615         mutex_unlock(&rx_queue_mutex);
1616 }
1617
1618 #define ISCSI_CLASS_ATTR(_prefix,_name,_mode,_show,_store)              \
1619 struct device_attribute dev_attr_##_prefix##_##_name =  \
1620         __ATTR(_name,_mode,_show,_store)
1621
1622 /*
1623  * iSCSI connection attrs
1624  */
1625 #define iscsi_conn_attr_show(param)                                     \
1626 static ssize_t                                                          \
1627 show_conn_param_##param(struct device *dev,                             \
1628                         struct device_attribute *attr, char *buf)       \
1629 {                                                                       \
1630         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev->parent);   \
1631         struct iscsi_transport *t = conn->transport;                    \
1632         return t->get_conn_param(conn, param, buf);                     \
1633 }
1634
1635 #define iscsi_conn_attr(field, param)                                   \
1636         iscsi_conn_attr_show(param)                                     \
1637 static ISCSI_CLASS_ATTR(conn, field, S_IRUGO, show_conn_param_##param,  \
1638                         NULL);
1639
1640 iscsi_conn_attr(max_recv_dlength, ISCSI_PARAM_MAX_RECV_DLENGTH);
1641 iscsi_conn_attr(max_xmit_dlength, ISCSI_PARAM_MAX_XMIT_DLENGTH);
1642 iscsi_conn_attr(header_digest, ISCSI_PARAM_HDRDGST_EN);
1643 iscsi_conn_attr(data_digest, ISCSI_PARAM_DATADGST_EN);
1644 iscsi_conn_attr(ifmarker, ISCSI_PARAM_IFMARKER_EN);
1645 iscsi_conn_attr(ofmarker, ISCSI_PARAM_OFMARKER_EN);
1646 iscsi_conn_attr(persistent_port, ISCSI_PARAM_PERSISTENT_PORT);
1647 iscsi_conn_attr(port, ISCSI_PARAM_CONN_PORT);
1648 iscsi_conn_attr(exp_statsn, ISCSI_PARAM_EXP_STATSN);
1649 iscsi_conn_attr(persistent_address, ISCSI_PARAM_PERSISTENT_ADDRESS);
1650 iscsi_conn_attr(address, ISCSI_PARAM_CONN_ADDRESS);
1651 iscsi_conn_attr(ping_tmo, ISCSI_PARAM_PING_TMO);
1652 iscsi_conn_attr(recv_tmo, ISCSI_PARAM_RECV_TMO);
1653
1654 /*
1655  * iSCSI session attrs
1656  */
1657 #define iscsi_session_attr_show(param, perm)                            \
1658 static ssize_t                                                          \
1659 show_session_param_##param(struct device *dev,                          \
1660                            struct device_attribute *attr, char *buf)    \
1661 {                                                                       \
1662         struct iscsi_cls_session *session =                             \
1663                 iscsi_dev_to_session(dev->parent);                      \
1664         struct iscsi_transport *t = session->transport;                 \
1665                                                                         \
1666         if (perm && !capable(CAP_SYS_ADMIN))                            \
1667                 return -EACCES;                                         \
1668         return t->get_session_param(session, param, buf);               \
1669 }
1670
1671 #define iscsi_session_attr(field, param, perm)                          \
1672         iscsi_session_attr_show(param, perm)                            \
1673 static ISCSI_CLASS_ATTR(sess, field, S_IRUGO, show_session_param_##param, \
1674                         NULL);
1675
1676 iscsi_session_attr(targetname, ISCSI_PARAM_TARGET_NAME, 0);
1677 iscsi_session_attr(initial_r2t, ISCSI_PARAM_INITIAL_R2T_EN, 0);
1678 iscsi_session_attr(max_outstanding_r2t, ISCSI_PARAM_MAX_R2T, 0);
1679 iscsi_session_attr(immediate_data, ISCSI_PARAM_IMM_DATA_EN, 0);
1680 iscsi_session_attr(first_burst_len, ISCSI_PARAM_FIRST_BURST, 0);
1681 iscsi_session_attr(max_burst_len, ISCSI_PARAM_MAX_BURST, 0);
1682 iscsi_session_attr(data_pdu_in_order, ISCSI_PARAM_PDU_INORDER_EN, 0);
1683 iscsi_session_attr(data_seq_in_order, ISCSI_PARAM_DATASEQ_INORDER_EN, 0);
1684 iscsi_session_attr(erl, ISCSI_PARAM_ERL, 0);
1685 iscsi_session_attr(tpgt, ISCSI_PARAM_TPGT, 0);
1686 iscsi_session_attr(username, ISCSI_PARAM_USERNAME, 1);
1687 iscsi_session_attr(username_in, ISCSI_PARAM_USERNAME_IN, 1);
1688 iscsi_session_attr(password, ISCSI_PARAM_PASSWORD, 1);
1689 iscsi_session_attr(password_in, ISCSI_PARAM_PASSWORD_IN, 1);
1690 iscsi_session_attr(fast_abort, ISCSI_PARAM_FAST_ABORT, 0);
1691 iscsi_session_attr(abort_tmo, ISCSI_PARAM_ABORT_TMO, 0);
1692 iscsi_session_attr(lu_reset_tmo, ISCSI_PARAM_LU_RESET_TMO, 0);
1693 iscsi_session_attr(ifacename, ISCSI_PARAM_IFACE_NAME, 0);
1694 iscsi_session_attr(initiatorname, ISCSI_PARAM_INITIATOR_NAME, 0)
1695
1696 static ssize_t
1697 show_priv_session_state(struct device *dev, struct device_attribute *attr,
1698                         char *buf)
1699 {
1700         struct iscsi_cls_session *session = iscsi_dev_to_session(dev->parent);
1701         return sprintf(buf, "%s\n", iscsi_session_state_name(session->state));
1702 }
1703 static ISCSI_CLASS_ATTR(priv_sess, state, S_IRUGO, show_priv_session_state,
1704                         NULL);
1705
1706 #define iscsi_priv_session_attr_show(field, format)                     \
1707 static ssize_t                                                          \
1708 show_priv_session_##field(struct device *dev,                           \
1709                           struct device_attribute *attr, char *buf)     \
1710 {                                                                       \
1711         struct iscsi_cls_session *session =                             \
1712                         iscsi_dev_to_session(dev->parent);              \
1713         return sprintf(buf, format"\n", session->field);                \
1714 }
1715
1716 #define iscsi_priv_session_attr(field, format)                          \
1717         iscsi_priv_session_attr_show(field, format)                     \
1718 static ISCSI_CLASS_ATTR(priv_sess, field, S_IRUGO, show_priv_session_##field, \
1719                         NULL)
1720 iscsi_priv_session_attr(recovery_tmo, "%d");
1721
1722 /*
1723  * iSCSI host attrs
1724  */
1725 #define iscsi_host_attr_show(param)                                     \
1726 static ssize_t                                                          \
1727 show_host_param_##param(struct device *dev,                             \
1728                         struct device_attribute *attr, char *buf)       \
1729 {                                                                       \
1730         struct Scsi_Host *shost = transport_class_to_shost(dev);        \
1731         struct iscsi_internal *priv = to_iscsi_internal(shost->transportt); \
1732         return priv->iscsi_transport->get_host_param(shost, param, buf); \
1733 }
1734
1735 #define iscsi_host_attr(field, param)                                   \
1736         iscsi_host_attr_show(param)                                     \
1737 static ISCSI_CLASS_ATTR(host, field, S_IRUGO, show_host_param_##param,  \
1738                         NULL);
1739
1740 iscsi_host_attr(netdev, ISCSI_HOST_PARAM_NETDEV_NAME);
1741 iscsi_host_attr(hwaddress, ISCSI_HOST_PARAM_HWADDRESS);
1742 iscsi_host_attr(ipaddress, ISCSI_HOST_PARAM_IPADDRESS);
1743 iscsi_host_attr(initiatorname, ISCSI_HOST_PARAM_INITIATOR_NAME);
1744
1745 #define SETUP_PRIV_SESSION_RD_ATTR(field)                               \
1746 do {                                                                    \
1747         priv->session_attrs[count] = &dev_attr_priv_sess_##field; \
1748         count++;                                                        \
1749 } while (0)
1750
1751
1752 #define SETUP_SESSION_RD_ATTR(field, param_flag)                        \
1753 do {                                                                    \
1754         if (tt->param_mask & param_flag) {                              \
1755                 priv->session_attrs[count] = &dev_attr_sess_##field; \
1756                 count++;                                                \
1757         }                                                               \
1758 } while (0)
1759
1760 #define SETUP_CONN_RD_ATTR(field, param_flag)                           \
1761 do {                                                                    \
1762         if (tt->param_mask & param_flag) {                              \
1763                 priv->conn_attrs[count] = &dev_attr_conn_##field; \
1764                 count++;                                                \
1765         }                                                               \
1766 } while (0)
1767
1768 #define SETUP_HOST_RD_ATTR(field, param_flag)                           \
1769 do {                                                                    \
1770         if (tt->host_param_mask & param_flag) {                         \
1771                 priv->host_attrs[count] = &dev_attr_host_##field; \
1772                 count++;                                                \
1773         }                                                               \
1774 } while (0)
1775
1776 static int iscsi_session_match(struct attribute_container *cont,
1777                            struct device *dev)
1778 {
1779         struct iscsi_cls_session *session;
1780         struct Scsi_Host *shost;
1781         struct iscsi_internal *priv;
1782
1783         if (!iscsi_is_session_dev(dev))
1784                 return 0;
1785
1786         session = iscsi_dev_to_session(dev);
1787         shost = iscsi_session_to_shost(session);
1788         if (!shost->transportt)
1789                 return 0;
1790
1791         priv = to_iscsi_internal(shost->transportt);
1792         if (priv->session_cont.ac.class != &iscsi_session_class.class)
1793                 return 0;
1794
1795         return &priv->session_cont.ac == cont;
1796 }
1797
1798 static int iscsi_conn_match(struct attribute_container *cont,
1799                            struct device *dev)
1800 {
1801         struct iscsi_cls_session *session;
1802         struct iscsi_cls_conn *conn;
1803         struct Scsi_Host *shost;
1804         struct iscsi_internal *priv;
1805
1806         if (!iscsi_is_conn_dev(dev))
1807                 return 0;
1808
1809         conn = iscsi_dev_to_conn(dev);
1810         session = iscsi_dev_to_session(conn->dev.parent);
1811         shost = iscsi_session_to_shost(session);
1812
1813         if (!shost->transportt)
1814                 return 0;
1815
1816         priv = to_iscsi_internal(shost->transportt);
1817         if (priv->conn_cont.ac.class != &iscsi_connection_class.class)
1818                 return 0;
1819
1820         return &priv->conn_cont.ac == cont;
1821 }
1822
1823 static int iscsi_host_match(struct attribute_container *cont,
1824                             struct device *dev)
1825 {
1826         struct Scsi_Host *shost;
1827         struct iscsi_internal *priv;
1828
1829         if (!scsi_is_host_device(dev))
1830                 return 0;
1831
1832         shost = dev_to_shost(dev);
1833         if (!shost->transportt  ||
1834             shost->transportt->host_attrs.ac.class != &iscsi_host_class.class)
1835                 return 0;
1836
1837         priv = to_iscsi_internal(shost->transportt);
1838         return &priv->t.host_attrs.ac == cont;
1839 }
1840
1841 struct scsi_transport_template *
1842 iscsi_register_transport(struct iscsi_transport *tt)
1843 {
1844         struct iscsi_internal *priv;
1845         unsigned long flags;
1846         int count = 0, err;
1847
1848         BUG_ON(!tt);
1849
1850         priv = iscsi_if_transport_lookup(tt);
1851         if (priv)
1852                 return NULL;
1853
1854         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1855         if (!priv)
1856                 return NULL;
1857         INIT_LIST_HEAD(&priv->list);
1858         priv->iscsi_transport = tt;
1859         priv->t.user_scan = iscsi_user_scan;
1860         priv->t.create_work_queue = 1;
1861
1862         priv->dev.class = &iscsi_transport_class;
1863         dev_set_name(&priv->dev, "%s", tt->name);
1864         err = device_register(&priv->dev);
1865         if (err)
1866                 goto free_priv;
1867
1868         err = sysfs_create_group(&priv->dev.kobj, &iscsi_transport_group);
1869         if (err)
1870                 goto unregister_dev;
1871
1872         /* host parameters */
1873         priv->t.host_attrs.ac.attrs = &priv->host_attrs[0];
1874         priv->t.host_attrs.ac.class = &iscsi_host_class.class;
1875         priv->t.host_attrs.ac.match = iscsi_host_match;
1876         priv->t.host_size = sizeof(struct iscsi_cls_host);
1877         transport_container_register(&priv->t.host_attrs);
1878
1879         SETUP_HOST_RD_ATTR(netdev, ISCSI_HOST_NETDEV_NAME);
1880         SETUP_HOST_RD_ATTR(ipaddress, ISCSI_HOST_IPADDRESS);
1881         SETUP_HOST_RD_ATTR(hwaddress, ISCSI_HOST_HWADDRESS);
1882         SETUP_HOST_RD_ATTR(initiatorname, ISCSI_HOST_INITIATOR_NAME);
1883         BUG_ON(count > ISCSI_HOST_ATTRS);
1884         priv->host_attrs[count] = NULL;
1885         count = 0;
1886
1887         /* connection parameters */
1888         priv->conn_cont.ac.attrs = &priv->conn_attrs[0];
1889         priv->conn_cont.ac.class = &iscsi_connection_class.class;
1890         priv->conn_cont.ac.match = iscsi_conn_match;
1891         transport_container_register(&priv->conn_cont);
1892
1893         SETUP_CONN_RD_ATTR(max_recv_dlength, ISCSI_MAX_RECV_DLENGTH);
1894         SETUP_CONN_RD_ATTR(max_xmit_dlength, ISCSI_MAX_XMIT_DLENGTH);
1895         SETUP_CONN_RD_ATTR(header_digest, ISCSI_HDRDGST_EN);
1896         SETUP_CONN_RD_ATTR(data_digest, ISCSI_DATADGST_EN);
1897         SETUP_CONN_RD_ATTR(ifmarker, ISCSI_IFMARKER_EN);
1898         SETUP_CONN_RD_ATTR(ofmarker, ISCSI_OFMARKER_EN);
1899         SETUP_CONN_RD_ATTR(address, ISCSI_CONN_ADDRESS);
1900         SETUP_CONN_RD_ATTR(port, ISCSI_CONN_PORT);
1901         SETUP_CONN_RD_ATTR(exp_statsn, ISCSI_EXP_STATSN);
1902         SETUP_CONN_RD_ATTR(persistent_address, ISCSI_PERSISTENT_ADDRESS);
1903         SETUP_CONN_RD_ATTR(persistent_port, ISCSI_PERSISTENT_PORT);
1904         SETUP_CONN_RD_ATTR(ping_tmo, ISCSI_PING_TMO);
1905         SETUP_CONN_RD_ATTR(recv_tmo, ISCSI_RECV_TMO);
1906
1907         BUG_ON(count > ISCSI_CONN_ATTRS);
1908         priv->conn_attrs[count] = NULL;
1909         count = 0;
1910
1911         /* session parameters */
1912         priv->session_cont.ac.attrs = &priv->session_attrs[0];
1913         priv->session_cont.ac.class = &iscsi_session_class.class;
1914         priv->session_cont.ac.match = iscsi_session_match;
1915         transport_container_register(&priv->session_cont);
1916
1917         SETUP_SESSION_RD_ATTR(initial_r2t, ISCSI_INITIAL_R2T_EN);
1918         SETUP_SESSION_RD_ATTR(max_outstanding_r2t, ISCSI_MAX_R2T);
1919         SETUP_SESSION_RD_ATTR(immediate_data, ISCSI_IMM_DATA_EN);
1920         SETUP_SESSION_RD_ATTR(first_burst_len, ISCSI_FIRST_BURST);
1921         SETUP_SESSION_RD_ATTR(max_burst_len, ISCSI_MAX_BURST);
1922         SETUP_SESSION_RD_ATTR(data_pdu_in_order, ISCSI_PDU_INORDER_EN);
1923         SETUP_SESSION_RD_ATTR(data_seq_in_order, ISCSI_DATASEQ_INORDER_EN);
1924         SETUP_SESSION_RD_ATTR(erl, ISCSI_ERL);
1925         SETUP_SESSION_RD_ATTR(targetname, ISCSI_TARGET_NAME);
1926         SETUP_SESSION_RD_ATTR(tpgt, ISCSI_TPGT);
1927         SETUP_SESSION_RD_ATTR(password, ISCSI_USERNAME);
1928         SETUP_SESSION_RD_ATTR(password_in, ISCSI_USERNAME_IN);
1929         SETUP_SESSION_RD_ATTR(username, ISCSI_PASSWORD);
1930         SETUP_SESSION_RD_ATTR(username_in, ISCSI_PASSWORD_IN);
1931         SETUP_SESSION_RD_ATTR(fast_abort, ISCSI_FAST_ABORT);
1932         SETUP_SESSION_RD_ATTR(abort_tmo, ISCSI_ABORT_TMO);
1933         SETUP_SESSION_RD_ATTR(lu_reset_tmo,ISCSI_LU_RESET_TMO);
1934         SETUP_SESSION_RD_ATTR(ifacename, ISCSI_IFACE_NAME);
1935         SETUP_SESSION_RD_ATTR(initiatorname, ISCSI_INITIATOR_NAME);
1936         SETUP_PRIV_SESSION_RD_ATTR(recovery_tmo);
1937         SETUP_PRIV_SESSION_RD_ATTR(state);
1938
1939         BUG_ON(count > ISCSI_SESSION_ATTRS);
1940         priv->session_attrs[count] = NULL;
1941
1942         spin_lock_irqsave(&iscsi_transport_lock, flags);
1943         list_add(&priv->list, &iscsi_transports);
1944         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1945
1946         printk(KERN_NOTICE "iscsi: registered transport (%s)\n", tt->name);
1947         return &priv->t;
1948
1949 unregister_dev:
1950         device_unregister(&priv->dev);
1951         return NULL;
1952 free_priv:
1953         kfree(priv);
1954         return NULL;
1955 }
1956 EXPORT_SYMBOL_GPL(iscsi_register_transport);
1957
1958 int iscsi_unregister_transport(struct iscsi_transport *tt)
1959 {
1960         struct iscsi_internal *priv;
1961         unsigned long flags;
1962
1963         BUG_ON(!tt);
1964
1965         mutex_lock(&rx_queue_mutex);
1966
1967         priv = iscsi_if_transport_lookup(tt);
1968         BUG_ON (!priv);
1969
1970         spin_lock_irqsave(&iscsi_transport_lock, flags);
1971         list_del(&priv->list);
1972         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1973
1974         transport_container_unregister(&priv->conn_cont);
1975         transport_container_unregister(&priv->session_cont);
1976         transport_container_unregister(&priv->t.host_attrs);
1977
1978         sysfs_remove_group(&priv->dev.kobj, &iscsi_transport_group);
1979         device_unregister(&priv->dev);
1980         mutex_unlock(&rx_queue_mutex);
1981
1982         return 0;
1983 }
1984 EXPORT_SYMBOL_GPL(iscsi_unregister_transport);
1985
1986 static __init int iscsi_transport_init(void)
1987 {
1988         int err;
1989
1990         printk(KERN_INFO "Loading iSCSI transport class v%s.\n",
1991                 ISCSI_TRANSPORT_VERSION);
1992
1993         atomic_set(&iscsi_session_nr, 0);
1994
1995         err = class_register(&iscsi_transport_class);
1996         if (err)
1997                 return err;
1998
1999         err = class_register(&iscsi_endpoint_class);
2000         if (err)
2001                 goto unregister_transport_class;
2002
2003         err = transport_class_register(&iscsi_host_class);
2004         if (err)
2005                 goto unregister_endpoint_class;
2006
2007         err = transport_class_register(&iscsi_connection_class);
2008         if (err)
2009                 goto unregister_host_class;
2010
2011         err = transport_class_register(&iscsi_session_class);
2012         if (err)
2013                 goto unregister_conn_class;
2014
2015         nls = netlink_kernel_create(&init_net, NETLINK_ISCSI, 1, iscsi_if_rx,
2016                                     NULL, THIS_MODULE);
2017         if (!nls) {
2018                 err = -ENOBUFS;
2019                 goto unregister_session_class;
2020         }
2021
2022         iscsi_eh_timer_workq = create_singlethread_workqueue("iscsi_eh");
2023         if (!iscsi_eh_timer_workq)
2024                 goto release_nls;
2025
2026         return 0;
2027
2028 release_nls:
2029         netlink_kernel_release(nls);
2030 unregister_session_class:
2031         transport_class_unregister(&iscsi_session_class);
2032 unregister_conn_class:
2033         transport_class_unregister(&iscsi_connection_class);
2034 unregister_host_class:
2035         transport_class_unregister(&iscsi_host_class);
2036 unregister_endpoint_class:
2037         class_unregister(&iscsi_endpoint_class);
2038 unregister_transport_class:
2039         class_unregister(&iscsi_transport_class);
2040         return err;
2041 }
2042
2043 static void __exit iscsi_transport_exit(void)
2044 {
2045         destroy_workqueue(iscsi_eh_timer_workq);
2046         netlink_kernel_release(nls);
2047         transport_class_unregister(&iscsi_connection_class);
2048         transport_class_unregister(&iscsi_session_class);
2049         transport_class_unregister(&iscsi_host_class);
2050         class_unregister(&iscsi_endpoint_class);
2051         class_unregister(&iscsi_transport_class);
2052 }
2053
2054 module_init(iscsi_transport_init);
2055 module_exit(iscsi_transport_exit);
2056
2057 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
2058               "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
2059               "Alex Aizman <itn780@yahoo.com>");
2060 MODULE_DESCRIPTION("iSCSI Transport Interface");
2061 MODULE_LICENSE("GPL");
2062 MODULE_VERSION(ISCSI_TRANSPORT_VERSION);