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

   1 /*
   2  * iSCSI transport class definitions
   3  *
   4  * Copyright (C) IBM Corporation, 2004
   5  * Copyright (C) Mike Christie, 2004 - 2005
   6  * Copyright (C) Dmitry Yusupov, 2004 - 2005
   7  * Copyright (C) Alex Aizman, 2004 - 2005
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  22  */
  23 #include <linux/module.h>
  24 #include <linux/mutex.h>
  25 #include <net/tcp.h>
  26 #include <scsi/scsi.h>
  27 #include <scsi/scsi_host.h>
  28 #include <scsi/scsi_device.h>
  29 #include <scsi/scsi_transport.h>
  30 #include <scsi/scsi_transport_iscsi.h>
  31 #include <scsi/iscsi_if.h>
  32
  33 #define ISCSI_SESSION_ATTRS 21
  34 #define ISCSI_CONN_ATTRS 13
  35 #define ISCSI_HOST_ATTRS 4
  36
  37 #define ISCSI_TRANSPORT_VERSION "2.0-870"
  38
  39 static int dbg_session;
  40 module_param_named(debug_session, dbg_session, int,
  41                    S_IRUGO | S_IWUSR);
  42 MODULE_PARM_DESC(debug_session,
  43                  "Turn on debugging for sessions in scsi_transport_iscsi "
  44                  "module. Set to 1 to turn on, and zero to turn off. Default "
  45                  "is off.");
  46
  47 static int dbg_conn;
  48 module_param_named(debug_conn, dbg_conn, int,
  49                    S_IRUGO | S_IWUSR);
  50 MODULE_PARM_DESC(debug_conn,
  51                  "Turn on debugging for connections in scsi_transport_iscsi "
  52                  "module. Set to 1 to turn on, and zero to turn off. Default "
  53                  "is off.");
  54
  55 #define ISCSI_DBG_TRANS_SESSION(_session, dbg_fmt, arg...)              \
  56         do {                                                            \
  57                 if (dbg_session)                                        \
  58                         iscsi_cls_session_printk(KERN_INFO, _session,   \
  59                                                  "%s: " dbg_fmt,        \
  60                                                  __func__, ##arg);      \
  61         } while (0);
  62
  63 #define ISCSI_DBG_TRANS_CONN(_conn, dbg_fmt, arg...)                    \
  64         do {                                                            \
  65                 if (dbg_conn)                                           \
  66                         iscsi_cls_conn_printk(KERN_INFO, _conn,         \
  67                                               "%s: " dbg_fmt,           \
  68                                               __func__, ##arg); \
  69         } while (0);
  70
  71 struct iscsi_internal {
  72         struct scsi_transport_template t;
  73         struct iscsi_transport *iscsi_transport;
  74         struct list_head list;
  75         struct device dev;
  76
  77         struct device_attribute *host_attrs[ISCSI_HOST_ATTRS + 1];
  78         struct transport_container conn_cont;
  79         struct device_attribute *conn_attrs[ISCSI_CONN_ATTRS + 1];
  80         struct transport_container session_cont;
  81         struct device_attribute *session_attrs[ISCSI_SESSION_ATTRS + 1];
  82 };
  83
  84 static atomic_t iscsi_session_nr; /* sysfs session id for next new session */
  85 static struct workqueue_struct *iscsi_eh_timer_workq;
  86
  87 /*
  88  * list of registered transports and lock that must
  89  * be held while accessing list. The iscsi_transport_lock must
  90  * be acquired after the rx_queue_mutex.
  91  */
  92 static LIST_HEAD(iscsi_transports);
  93 static DEFINE_SPINLOCK(iscsi_transport_lock);
  94
  95 #define to_iscsi_internal(tmpl) \
  96         container_of(tmpl, struct iscsi_internal, t)
  97
  98 #define dev_to_iscsi_internal(_dev) \
  99         container_of(_dev, struct iscsi_internal, dev)
 100
 101 static void iscsi_transport_release(struct device *dev)
 102 {
 103         struct iscsi_internal *priv = dev_to_iscsi_internal(dev);
 104         kfree(priv);
 105 }
 106
 107 /*
 108  * iscsi_transport_class represents the iscsi_transports that are
 109  * registered.
 110  */
 111 static struct class iscsi_transport_class = {
 112         .name = "iscsi_transport",
 113         .dev_release = iscsi_transport_release,
 114 };
 115
 116 static ssize_t
 117 show_transport_handle(struct device *dev, struct device_attribute *attr,
 118                       char *buf)
 119 {
 120         struct iscsi_internal *priv = dev_to_iscsi_internal(dev);
 121         return sprintf(buf, "%llu\n", (unsigned long long)iscsi_handle(priv->iscsi_transport));
 122 }
 123 static DEVICE_ATTR(handle, S_IRUGO, show_transport_handle, NULL);
 124
 125 #define show_transport_attr(name, format)                               \
 126 static ssize_t                                                          \
 127 show_transport_##name(struct device *dev,                               \
 128                       struct device_attribute *attr,char *buf)          \
 129 {                                                                       \
 130         struct iscsi_internal *priv = dev_to_iscsi_internal(dev);       \
 131         return sprintf(buf, format"\n", priv->iscsi_transport->name);   \
 132 }                                                                       \
 133 static DEVICE_ATTR(name, S_IRUGO, show_transport_##name, NULL);
 134
 135 show_transport_attr(caps, "0x%x");
 136
 137 static struct attribute *iscsi_transport_attrs[] = {
 138         &dev_attr_handle.attr,
 139         &dev_attr_caps.attr,
 140         NULL,
 141 };
 142
 143 static struct attribute_group iscsi_transport_group = {
 144         .attrs = iscsi_transport_attrs,
 145 };
 146
 147 /*
 148  * iSCSI endpoint attrs
 149  */
 150 #define iscsi_dev_to_endpoint(_dev) \
 151         container_of(_dev, struct iscsi_endpoint, dev)
 152
 153 #define ISCSI_ATTR(_prefix,_name,_mode,_show,_store)    \
 154 struct device_attribute dev_attr_##_prefix##_##_name =  \
 155         __ATTR(_name,_mode,_show,_store)
 156
 157 static void iscsi_endpoint_release(struct device *dev)
 158 {
 159         struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
 160         kfree(ep);
 161 }
 162
 163 static struct class iscsi_endpoint_class = {
 164         .name = "iscsi_endpoint",
 165         .dev_release = iscsi_endpoint_release,
 166 };
 167
 168 static ssize_t
 169 show_ep_handle(struct device *dev, struct device_attribute *attr, char *buf)
 170 {
 171         struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
 172         return sprintf(buf, "%llu\n", (unsigned long long) ep->id);
 173 }
 174 static ISCSI_ATTR(ep, handle, S_IRUGO, show_ep_handle, NULL);
 175
 176 static struct attribute *iscsi_endpoint_attrs[] = {
 177         &dev_attr_ep_handle.attr,
 178         NULL,
 179 };
 180
 181 static struct attribute_group iscsi_endpoint_group = {
 182         .attrs = iscsi_endpoint_attrs,
 183 };
 184
 185 #define ISCSI_MAX_EPID -1
 186
 187 static int iscsi_match_epid(struct device *dev, void *data)
 188 {
 189         struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
 190         uint64_t *epid = (uint64_t *) data;
 191
 192         return *epid == ep->id;
 193 }
 194
 195 struct iscsi_endpoint *
 196 iscsi_create_endpoint(int dd_size)
 197 {
 198         struct device *dev;
 199         struct iscsi_endpoint *ep;
 200         uint64_t id;
 201         int err;
 202
 203         for (id = 1; id < ISCSI_MAX_EPID; id++) {
 204                 dev = class_find_device(&iscsi_endpoint_class, NULL, &id,
 205                                         iscsi_match_epid);
 206                 if (!dev)
 207                         break;
 208         }
 209         if (id == ISCSI_MAX_EPID) {
 210                 printk(KERN_ERR "Too many connections. Max supported %u\n",
 211                        ISCSI_MAX_EPID - 1);
 212                 return NULL;
 213         }
 214
 215         ep = kzalloc(sizeof(*ep) + dd_size, GFP_KERNEL);
 216         if (!ep)
 217                 return NULL;
 218
 219         ep->id = id;
 220         ep->dev.class = &iscsi_endpoint_class;
 221         dev_set_name(&ep->dev, "ep-%llu", (unsigned long long) id);
 222         err = device_register(&ep->dev);
 223         if (err)
 224                 goto free_ep;
 225
 226         err = sysfs_create_group(&ep->dev.kobj, &iscsi_endpoint_group);
 227         if (err)
 228                 goto unregister_dev;
 229
 230         if (dd_size)
 231                 ep->dd_data = &ep[1];
 232         return ep;
 233
 234 unregister_dev:
 235         device_unregister(&ep->dev);
 236         return NULL;
 237
 238 free_ep:
 239         kfree(ep);
 240         return NULL;
 241 }
 242 EXPORT_SYMBOL_GPL(iscsi_create_endpoint);
 243
 244 void iscsi_destroy_endpoint(struct iscsi_endpoint *ep)
 245 {
 246         sysfs_remove_group(&ep->dev.kobj, &iscsi_endpoint_group);
 247         device_unregister(&ep->dev);
 248 }
 249 EXPORT_SYMBOL_GPL(iscsi_destroy_endpoint);
 250
 251 struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle)
 252 {
 253         struct iscsi_endpoint *ep;
 254         struct device *dev;
 255
 256         dev = class_find_device(&iscsi_endpoint_class, NULL, &handle,
 257                                 iscsi_match_epid);
 258         if (!dev)
 259                 return NULL;
 260
 261         ep = iscsi_dev_to_endpoint(dev);
 262         /*
 263          * we can drop this now because the interface will prevent
 264          * removals and lookups from racing.
 265          */
 266         put_device(dev);
 267         return ep;
 268 }
 269 EXPORT_SYMBOL_GPL(iscsi_lookup_endpoint);
 270
 271 static int iscsi_setup_host(struct transport_container *tc, struct device *dev,
 272                             struct device *cdev)
 273 {
 274         struct Scsi_Host *shost = dev_to_shost(dev);
 275         struct iscsi_cls_host *ihost = shost->shost_data;
 276
 277         memset(ihost, 0, sizeof(*ihost));
 278         atomic_set(&ihost->nr_scans, 0);
 279         mutex_init(&ihost->mutex);
 280         return 0;
 281 }
 282
 283 static DECLARE_TRANSPORT_CLASS(iscsi_host_class,
 284                                "iscsi_host",
 285                                iscsi_setup_host,
 286                                NULL,
 287                                NULL);
 288
 289 static DECLARE_TRANSPORT_CLASS(iscsi_session_class,
 290                                "iscsi_session",
 291                                NULL,
 292                                NULL,
 293                                NULL);
 294
 295 static DECLARE_TRANSPORT_CLASS(iscsi_connection_class,
 296                                "iscsi_connection",
 297                                NULL,
 298                                NULL,
 299                                NULL);
 300
 301 static struct sock *nls;
 302 static DEFINE_MUTEX(rx_queue_mutex);
 303
 304 static LIST_HEAD(sesslist);
 305 static DEFINE_SPINLOCK(sesslock);
 306 static LIST_HEAD(connlist);
 307 static DEFINE_SPINLOCK(connlock);
 308
 309 static uint32_t iscsi_conn_get_sid(struct iscsi_cls_conn *conn)
 310 {
 311         struct iscsi_cls_session *sess = iscsi_dev_to_session(conn->dev.parent);
 312         return sess->sid;
 313 }
 314
 315 /*
 316  * Returns the matching session to a given sid
 317  */
 318 static struct iscsi_cls_session *iscsi_session_lookup(uint32_t sid)
 319 {
 320         unsigned long flags;
 321         struct iscsi_cls_session *sess;
 322
 323         spin_lock_irqsave(&sesslock, flags);
 324         list_for_each_entry(sess, &sesslist, sess_list) {
 325                 if (sess->sid == sid) {
 326                         spin_unlock_irqrestore(&sesslock, flags);
 327                         return sess;
 328                 }
 329         }
 330         spin_unlock_irqrestore(&sesslock, flags);
 331         return NULL;
 332 }
 333
 334 /*
 335  * Returns the matching connection to a given sid / cid tuple
 336  */
 337 static struct iscsi_cls_conn *iscsi_conn_lookup(uint32_t sid, uint32_t cid)
 338 {
 339         unsigned long flags;
 340         struct iscsi_cls_conn *conn;
 341
 342         spin_lock_irqsave(&connlock, flags);
 343         list_for_each_entry(conn, &connlist, conn_list) {
 344                 if ((conn->cid == cid) && (iscsi_conn_get_sid(conn) == sid)) {
 345                         spin_unlock_irqrestore(&connlock, flags);
 346                         return conn;
 347                 }
 348         }
 349         spin_unlock_irqrestore(&connlock, flags);
 350         return NULL;
 351 }
 352
 353 /*
 354  * The following functions can be used by LLDs that allocate
 355  * their own scsi_hosts or by software iscsi LLDs
 356  */
 357 static struct {
 358         int value;
 359         char *name;
 360 } iscsi_session_state_names[] = {
 361         { ISCSI_SESSION_LOGGED_IN,      "LOGGED_IN" },
 362         { ISCSI_SESSION_FAILED,         "FAILED" },
 363         { ISCSI_SESSION_FREE,           "FREE" },
 364 };
 365
 366 static const char *iscsi_session_state_name(int state)
 367 {
 368         int i;
 369         char *name = NULL;
 370
 371         for (i = 0; i < ARRAY_SIZE(iscsi_session_state_names); i++) {
 372                 if (iscsi_session_state_names[i].value == state) {
 373                         name = iscsi_session_state_names[i].name;
 374                         break;
 375                 }
 376         }
 377         return name;
 378 }
 379
 380 int iscsi_session_chkready(struct iscsi_cls_session *session)
 381 {
 382         unsigned long flags;
 383         int err;
 384
 385         spin_lock_irqsave(&session->lock, flags);
 386         switch (session->state) {
 387         case ISCSI_SESSION_LOGGED_IN:
 388                 err = 0;
 389                 break;
 390         case ISCSI_SESSION_FAILED:
 391                 err = DID_IMM_RETRY << 16;
 392                 break;
 393         case ISCSI_SESSION_FREE:
 394                 err = DID_TRANSPORT_FAILFAST << 16;
 395                 break;
 396         default:
 397                 err = DID_NO_CONNECT << 16;
 398                 break;
 399         }
 400         spin_unlock_irqrestore(&session->lock, flags);
 401         return err;
 402 }
 403 EXPORT_SYMBOL_GPL(iscsi_session_chkready);
 404
 405 static void iscsi_session_release(struct device *dev)
 406 {
 407         struct iscsi_cls_session *session = iscsi_dev_to_session(dev);
 408         struct Scsi_Host *shost;
 409
 410         shost = iscsi_session_to_shost(session);
 411         scsi_host_put(shost);
 412         ISCSI_DBG_TRANS_SESSION(session, "Completing session release\n");
 413         kfree(session);
 414 }
 415
 416 static int iscsi_is_session_dev(const struct device *dev)
 417 {
 418         return dev->release == iscsi_session_release;
 419 }
 420
 421 static int iscsi_iter_session_fn(struct device *dev, void *data)
 422 {
 423         void (* fn) (struct iscsi_cls_session *) = data;
 424
 425         if (!iscsi_is_session_dev(dev))
 426                 return 0;
 427         fn(iscsi_dev_to_session(dev));
 428         return 0;
 429 }
 430
 431 void iscsi_host_for_each_session(struct Scsi_Host *shost,
 432                                  void (*fn)(struct iscsi_cls_session *))
 433 {
 434         device_for_each_child(&shost->shost_gendev, fn,
 435                               iscsi_iter_session_fn);
 436 }
 437 EXPORT_SYMBOL_GPL(iscsi_host_for_each_session);
 438
 439 /**
 440  * iscsi_scan_finished - helper to report when running scans are done
 441  * @shost: scsi host
 442  * @time: scan run time
 443  *
 444  * This function can be used by drives like qla4xxx to report to the scsi
 445  * layer when the scans it kicked off at module load time are done.
 446  */
 447 int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time)
 448 {
 449         struct iscsi_cls_host *ihost = shost->shost_data;
 450         /*
 451          * qla4xxx will have kicked off some session unblocks before calling
 452          * scsi_scan_host, so just wait for them to complete.
 453          */
 454         return !atomic_read(&ihost->nr_scans);
 455 }
 456 EXPORT_SYMBOL_GPL(iscsi_scan_finished);
 457
 458 struct iscsi_scan_data {
 459         unsigned int channel;
 460         unsigned int id;
 461         unsigned int lun;
 462 };
 463
 464 static int iscsi_user_scan_session(struct device *dev, void *data)
 465 {
 466         struct iscsi_scan_data *scan_data = data;
 467         struct iscsi_cls_session *session;
 468         struct Scsi_Host *shost;
 469         struct iscsi_cls_host *ihost;
 470         unsigned long flags;
 471         unsigned int id;
 472
 473         if (!iscsi_is_session_dev(dev))
 474                 return 0;
 475
 476         session = iscsi_dev_to_session(dev);
 477
 478         ISCSI_DBG_TRANS_SESSION(session, "Scanning session\n");
 479
 480         shost = iscsi_session_to_shost(session);
 481         ihost = shost->shost_data;
 482
 483         mutex_lock(&ihost->mutex);
 484         spin_lock_irqsave(&session->lock, flags);
 485         if (session->state != ISCSI_SESSION_LOGGED_IN) {
 486                 spin_unlock_irqrestore(&session->lock, flags);
 487                 goto user_scan_exit;
 488         }
 489         id = session->target_id;
 490         spin_unlock_irqrestore(&session->lock, flags);
 491
 492         if (id != ISCSI_MAX_TARGET) {
 493                 if ((scan_data->channel == SCAN_WILD_CARD ||
 494                      scan_data->channel == 0) &&
 495                     (scan_data->id == SCAN_WILD_CARD ||
 496                      scan_data->id == id))
 497                         scsi_scan_target(&session->dev, 0, id,
 498                                          scan_data->lun, 1);
 499         }
 500
 501 user_scan_exit:
 502         mutex_unlock(&ihost->mutex);
 503         ISCSI_DBG_TRANS_SESSION(session, "Completed session scan\n");
 504         return 0;
 505 }
 506
 507 static int iscsi_user_scan(struct Scsi_Host *shost, uint channel,
 508                            uint id, uint lun)
 509 {
 510         struct iscsi_scan_data scan_data;
 511
 512         scan_data.channel = channel;
 513         scan_data.id = id;
 514         scan_data.lun = lun;
 515
 516         return device_for_each_child(&shost->shost_gendev, &scan_data,
 517                                      iscsi_user_scan_session);
 518 }
 519
 520 static void iscsi_scan_session(struct work_struct *work)
 521 {
 522         struct iscsi_cls_session *session =
 523                         container_of(work, struct iscsi_cls_session, scan_work);
 524         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 525         struct iscsi_cls_host *ihost = shost->shost_data;
 526         struct iscsi_scan_data scan_data;
 527
 528         scan_data.channel = 0;
 529         scan_data.id = SCAN_WILD_CARD;
 530         scan_data.lun = SCAN_WILD_CARD;
 531
 532         iscsi_user_scan_session(&session->dev, &scan_data);
 533         atomic_dec(&ihost->nr_scans);
 534 }
 535
 536 static void session_recovery_timedout(struct work_struct *work)
 537 {
 538         struct iscsi_cls_session *session =
 539                 container_of(work, struct iscsi_cls_session,
 540                              recovery_work.work);
 541         unsigned long flags;
 542
 543         iscsi_cls_session_printk(KERN_INFO, session,
 544                                  "session recovery timed out after %d secs\n",
 545                                  session->recovery_tmo);
 546
 547         spin_lock_irqsave(&session->lock, flags);
 548         switch (session->state) {
 549         case ISCSI_SESSION_FAILED:
 550                 session->state = ISCSI_SESSION_FREE;
 551                 break;
 552         case ISCSI_SESSION_LOGGED_IN:
 553         case ISCSI_SESSION_FREE:
 554                 /* we raced with the unblock's flush */
 555                 spin_unlock_irqrestore(&session->lock, flags);
 556                 return;
 557         }
 558         spin_unlock_irqrestore(&session->lock, flags);
 559
 560         if (session->transport->session_recovery_timedout)
 561                 session->transport->session_recovery_timedout(session);
 562
 563         ISCSI_DBG_TRANS_SESSION(session, "Unblocking SCSI target\n");
 564         scsi_target_unblock(&session->dev);
 565         ISCSI_DBG_TRANS_SESSION(session, "Completed unblocking SCSI target\n");
 566 }
 567
 568 static void __iscsi_unblock_session(struct work_struct *work)
 569 {
 570         struct iscsi_cls_session *session =
 571                         container_of(work, struct iscsi_cls_session,
 572                                      unblock_work);
 573         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 574         struct iscsi_cls_host *ihost = shost->shost_data;
 575         unsigned long flags;
 576
 577         ISCSI_DBG_TRANS_SESSION(session, "Unblocking session\n");
 578         /*
 579          * The recovery and unblock work get run from the same workqueue,
 580          * so try to cancel it if it was going to run after this unblock.
 581          */
 582         cancel_delayed_work(&session->recovery_work);
 583         spin_lock_irqsave(&session->lock, flags);
 584         session->state = ISCSI_SESSION_LOGGED_IN;
 585         spin_unlock_irqrestore(&session->lock, flags);
 586         /* start IO */
 587         scsi_target_unblock(&session->dev);
 588         /*
 589          * Only do kernel scanning if the driver is properly hooked into
 590          * the async scanning code (drivers like iscsi_tcp do login and
 591          * scanning from userspace).
 592          */
 593         if (shost->hostt->scan_finished) {
 594                 if (scsi_queue_work(shost, &session->scan_work))
 595                         atomic_inc(&ihost->nr_scans);
 596         }
 597         ISCSI_DBG_TRANS_SESSION(session, "Completed unblocking session\n");
 598 }
 599
 600 /**
 601  * iscsi_unblock_session - set a session as logged in and start IO.
 602  * @session: iscsi session
 603  *
 604  * Mark a session as ready to accept IO.
 605  */
 606 void iscsi_unblock_session(struct iscsi_cls_session *session)
 607 {
 608         queue_work(iscsi_eh_timer_workq, &session->unblock_work);
 609         /*
 610          * make sure all the events have completed before tell the driver
 611          * it is safe
 612          */
 613         flush_workqueue(iscsi_eh_timer_workq);
 614 }
 615 EXPORT_SYMBOL_GPL(iscsi_unblock_session);
 616
 617 static void __iscsi_block_session(struct work_struct *work)
 618 {
 619         struct iscsi_cls_session *session =
 620                         container_of(work, struct iscsi_cls_session,
 621                                      block_work);
 622         unsigned long flags;
 623
 624         ISCSI_DBG_TRANS_SESSION(session, "Blocking session\n");
 625         spin_lock_irqsave(&session->lock, flags);
 626         session->state = ISCSI_SESSION_FAILED;
 627         spin_unlock_irqrestore(&session->lock, flags);
 628         scsi_target_block(&session->dev);
 629         ISCSI_DBG_TRANS_SESSION(session, "Completed SCSI target blocking\n");
 630         queue_delayed_work(iscsi_eh_timer_workq, &session->recovery_work,
 631                            session->recovery_tmo * HZ);
 632 }
 633
 634 void iscsi_block_session(struct iscsi_cls_session *session)
 635 {
 636         queue_work(iscsi_eh_timer_workq, &session->block_work);
 637 }
 638 EXPORT_SYMBOL_GPL(iscsi_block_session);
 639
 640 static void __iscsi_unbind_session(struct work_struct *work)
 641 {
 642         struct iscsi_cls_session *session =
 643                         container_of(work, struct iscsi_cls_session,
 644                                      unbind_work);
 645         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 646         struct iscsi_cls_host *ihost = shost->shost_data;
 647         unsigned long flags;
 648
 649         ISCSI_DBG_TRANS_SESSION(session, "Unbinding session\n");
 650
 651         /* Prevent new scans and make sure scanning is not in progress */
 652         mutex_lock(&ihost->mutex);
 653         spin_lock_irqsave(&session->lock, flags);
 654         if (session->target_id == ISCSI_MAX_TARGET) {
 655                 spin_unlock_irqrestore(&session->lock, flags);
 656                 mutex_unlock(&ihost->mutex);
 657                 return;
 658         }
 659         session->target_id = ISCSI_MAX_TARGET;
 660         spin_unlock_irqrestore(&session->lock, flags);
 661         mutex_unlock(&ihost->mutex);
 662
 663         scsi_remove_target(&session->dev);
 664         iscsi_session_event(session, ISCSI_KEVENT_UNBIND_SESSION);
 665         ISCSI_DBG_TRANS_SESSION(session, "Completed target removal\n");
 666 }
 667
 668 struct iscsi_cls_session *
 669 iscsi_alloc_session(struct Scsi_Host *shost, struct iscsi_transport *transport,
 670                     int dd_size)
 671 {
 672         struct iscsi_cls_session *session;
 673
 674         session = kzalloc(sizeof(*session) + dd_size,
 675                           GFP_KERNEL);
 676         if (!session)
 677                 return NULL;
 678
 679         session->transport = transport;
 680         session->recovery_tmo = 120;
 681         session->state = ISCSI_SESSION_FREE;
 682         INIT_DELAYED_WORK(&session->recovery_work, session_recovery_timedout);
 683         INIT_LIST_HEAD(&session->sess_list);
 684         INIT_WORK(&session->unblock_work, __iscsi_unblock_session);
 685         INIT_WORK(&session->block_work, __iscsi_block_session);
 686         INIT_WORK(&session->unbind_work, __iscsi_unbind_session);
 687         INIT_WORK(&session->scan_work, iscsi_scan_session);
 688         spin_lock_init(&session->lock);
 689
 690         /* this is released in the dev's release function */
 691         scsi_host_get(shost);
 692         session->dev.parent = &shost->shost_gendev;
 693         session->dev.release = iscsi_session_release;
 694         device_initialize(&session->dev);
 695         if (dd_size)
 696                 session->dd_data = &session[1];
 697
 698         ISCSI_DBG_TRANS_SESSION(session, "Completed session allocation\n");
 699         return session;
 700 }
 701 EXPORT_SYMBOL_GPL(iscsi_alloc_session);
 702
 703 static int iscsi_get_next_target_id(struct device *dev, void *data)
 704 {
 705         struct iscsi_cls_session *session;
 706         unsigned long flags;
 707         int err = 0;
 708
 709         if (!iscsi_is_session_dev(dev))
 710                 return 0;
 711
 712         session = iscsi_dev_to_session(dev);
 713         spin_lock_irqsave(&session->lock, flags);
 714         if (*((unsigned int *) data) == session->target_id)
 715                 err = -EEXIST;
 716         spin_unlock_irqrestore(&session->lock, flags);
 717         return err;
 718 }
 719
 720 int iscsi_add_session(struct iscsi_cls_session *session, unsigned int target_id)
 721 {
 722         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 723         struct iscsi_cls_host *ihost;
 724         unsigned long flags;
 725         unsigned int id = target_id;
 726         int err;
 727
 728         ihost = shost->shost_data;
 729         session->sid = atomic_add_return(1, &iscsi_session_nr);
 730
 731         if (id == ISCSI_MAX_TARGET) {
 732                 for (id = 0; id < ISCSI_MAX_TARGET; id++) {
 733                         err = device_for_each_child(&shost->shost_gendev, &id,
 734                                                     iscsi_get_next_target_id);
 735                         if (!err)
 736                                 break;
 737                 }
 738
 739                 if (id == ISCSI_MAX_TARGET) {
 740                         iscsi_cls_session_printk(KERN_ERR, session,
 741                                                  "Too many iscsi targets. Max "
 742                                                  "number of targets is %d.\n",
 743                                                  ISCSI_MAX_TARGET - 1);
 744                         err = -EOVERFLOW;
 745                         goto release_host;
 746                 }
 747         }
 748         session->target_id = id;
 749
 750         dev_set_name(&session->dev, "session%u", session->sid);
 751         err = device_add(&session->dev);
 752         if (err) {
 753                 iscsi_cls_session_printk(KERN_ERR, session,
 754                                          "could not register session's dev\n");
 755                 goto release_host;
 756         }
 757         transport_register_device(&session->dev);
 758
 759         spin_lock_irqsave(&sesslock, flags);
 760         list_add(&session->sess_list, &sesslist);
 761         spin_unlock_irqrestore(&sesslock, flags);
 762
 763         iscsi_session_event(session, ISCSI_KEVENT_CREATE_SESSION);
 764         ISCSI_DBG_TRANS_SESSION(session, "Completed session adding\n");
 765         return 0;
 766
 767 release_host:
 768         scsi_host_put(shost);
 769         return err;
 770 }
 771 EXPORT_SYMBOL_GPL(iscsi_add_session);
 772
 773 /**
 774  * iscsi_create_session - create iscsi class session
 775  * @shost: scsi host
 776  * @transport: iscsi transport
 777  * @dd_size: private driver data size
 778  * @target_id: which target
 779  *
 780  * This can be called from a LLD or iscsi_transport.
 781  */
 782 struct iscsi_cls_session *
 783 iscsi_create_session(struct Scsi_Host *shost, struct iscsi_transport *transport,
 784                      int dd_size, unsigned int target_id)
 785 {
 786         struct iscsi_cls_session *session;
 787
 788         session = iscsi_alloc_session(shost, transport, dd_size);
 789         if (!session)
 790                 return NULL;
 791
 792         if (iscsi_add_session(session, target_id)) {
 793                 iscsi_free_session(session);
 794                 return NULL;
 795         }
 796         return session;
 797 }
 798 EXPORT_SYMBOL_GPL(iscsi_create_session);
 799
 800 static void iscsi_conn_release(struct device *dev)
 801 {
 802         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev);
 803         struct device *parent = conn->dev.parent;
 804
 805         ISCSI_DBG_TRANS_CONN(conn, "Releasing conn\n");
 806         kfree(conn);
 807         put_device(parent);
 808 }
 809
 810 static int iscsi_is_conn_dev(const struct device *dev)
 811 {
 812         return dev->release == iscsi_conn_release;
 813 }
 814
 815 static int iscsi_iter_destroy_conn_fn(struct device *dev, void *data)
 816 {
 817         if (!iscsi_is_conn_dev(dev))
 818                 return 0;
 819         return iscsi_destroy_conn(iscsi_dev_to_conn(dev));
 820 }
 821
 822 void iscsi_remove_session(struct iscsi_cls_session *session)
 823 {
 824         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 825         unsigned long flags;
 826         int err;
 827
 828         ISCSI_DBG_TRANS_SESSION(session, "Removing session\n");
 829
 830         spin_lock_irqsave(&sesslock, flags);
 831         list_del(&session->sess_list);
 832         spin_unlock_irqrestore(&sesslock, flags);
 833
 834         /* make sure there are no blocks/unblocks queued */
 835         flush_workqueue(iscsi_eh_timer_workq);
 836         /* make sure the timedout callout is not running */
 837         if (!cancel_delayed_work(&session->recovery_work))
 838                 flush_workqueue(iscsi_eh_timer_workq);
 839         /*
 840          * If we are blocked let commands flow again. The lld or iscsi
 841          * layer should set up the queuecommand to fail commands.
 842          * We assume that LLD will not be calling block/unblock while
 843          * removing the session.
 844          */
 845         spin_lock_irqsave(&session->lock, flags);
 846         session->state = ISCSI_SESSION_FREE;
 847         spin_unlock_irqrestore(&session->lock, flags);
 848
 849         scsi_target_unblock(&session->dev);
 850         /* flush running scans then delete devices */
 851         scsi_flush_work(shost);
 852         __iscsi_unbind_session(&session->unbind_work);
 853
 854         /* hw iscsi may not have removed all connections from session */
 855         err = device_for_each_child(&session->dev, NULL,
 856                                     iscsi_iter_destroy_conn_fn);
 857         if (err)
 858                 iscsi_cls_session_printk(KERN_ERR, session,
 859                                          "Could not delete all connections "
 860                                          "for session. Error %d.\n", err);
 861
 862         transport_unregister_device(&session->dev);
 863
 864         ISCSI_DBG_TRANS_SESSION(session, "Completing session removal\n");
 865         device_del(&session->dev);
 866 }
 867 EXPORT_SYMBOL_GPL(iscsi_remove_session);
 868
 869 void iscsi_free_session(struct iscsi_cls_session *session)
 870 {
 871         ISCSI_DBG_TRANS_SESSION(session, "Freeing session\n");
 872         iscsi_session_event(session, ISCSI_KEVENT_DESTROY_SESSION);
 873         put_device(&session->dev);
 874 }
 875 EXPORT_SYMBOL_GPL(iscsi_free_session);
 876
 877 /**
 878  * iscsi_destroy_session - destroy iscsi session
 879  * @session: iscsi_session
 880  *
 881  * Can be called by a LLD or iscsi_transport. There must not be
 882  * any running connections.
 883  */
 884 int iscsi_destroy_session(struct iscsi_cls_session *session)
 885 {
 886         iscsi_remove_session(session);
 887         ISCSI_DBG_TRANS_SESSION(session, "Completing session destruction\n");
 888         iscsi_free_session(session);
 889         return 0;
 890 }
 891 EXPORT_SYMBOL_GPL(iscsi_destroy_session);
 892
 893 /**
 894  * iscsi_create_conn - create iscsi class connection
 895  * @session: iscsi cls session
 896  * @dd_size: private driver data size
 897  * @cid: connection id
 898  *
 899  * This can be called from a LLD or iscsi_transport. The connection
 900  * is child of the session so cid must be unique for all connections
 901  * on the session.
 902  *
 903  * Since we do not support MCS, cid will normally be zero. In some cases
 904  * for software iscsi we could be trying to preallocate a connection struct
 905  * in which case there could be two connection structs and cid would be
 906  * non-zero.
 907  */
 908 struct iscsi_cls_conn *
 909 iscsi_create_conn(struct iscsi_cls_session *session, int dd_size, uint32_t cid)
 910 {
 911         struct iscsi_transport *transport = session->transport;
 912         struct iscsi_cls_conn *conn;
 913         unsigned long flags;
 914         int err;
 915
 916         conn = kzalloc(sizeof(*conn) + dd_size, GFP_KERNEL);
 917         if (!conn)
 918                 return NULL;
 919         if (dd_size)
 920                 conn->dd_data = &conn[1];
 921
 922         INIT_LIST_HEAD(&conn->conn_list);
 923         conn->transport = transport;
 924         conn->cid = cid;
 925
 926         /* this is released in the dev's release function */
 927         if (!get_device(&session->dev))
 928                 goto free_conn;
 929
 930         dev_set_name(&conn->dev, "connection%d:%u", session->sid, cid);
 931         conn->dev.parent = &session->dev;
 932         conn->dev.release = iscsi_conn_release;
 933         err = device_register(&conn->dev);
 934         if (err) {
 935                 iscsi_cls_session_printk(KERN_ERR, session, "could not "
 936                                          "register connection's dev\n");
 937                 goto release_parent_ref;
 938         }
 939         transport_register_device(&conn->dev);
 940
 941         spin_lock_irqsave(&connlock, flags);
 942         list_add(&conn->conn_list, &connlist);
 943         conn->active = 1;
 944         spin_unlock_irqrestore(&connlock, flags);
 945
 946         ISCSI_DBG_TRANS_CONN(conn, "Completed conn creation\n");
 947         return conn;
 948
 949 release_parent_ref:
 950         put_device(&session->dev);
 951 free_conn:
 952         kfree(conn);
 953         return NULL;
 954 }
 955
 956 EXPORT_SYMBOL_GPL(iscsi_create_conn);
 957
 958 /**
 959  * iscsi_destroy_conn - destroy iscsi class connection
 960  * @conn: iscsi cls session
 961  *
 962  * This can be called from a LLD or iscsi_transport.
 963  */
 964 int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
 965 {
 966         unsigned long flags;
 967
 968         spin_lock_irqsave(&connlock, flags);
 969         conn->active = 0;
 970         list_del(&conn->conn_list);
 971         spin_unlock_irqrestore(&connlock, flags);
 972
 973         transport_unregister_device(&conn->dev);
 974         ISCSI_DBG_TRANS_CONN(conn, "Completing conn destruction\n");
 975         device_unregister(&conn->dev);
 976         return 0;
 977 }
 978 EXPORT_SYMBOL_GPL(iscsi_destroy_conn);
 979
 980 /*
 981  * iscsi interface functions
 982  */
 983 static struct iscsi_internal *
 984 iscsi_if_transport_lookup(struct iscsi_transport *tt)
 985 {
 986         struct iscsi_internal *priv;
 987         unsigned long flags;
 988
 989         spin_lock_irqsave(&iscsi_transport_lock, flags);
 990         list_for_each_entry(priv, &iscsi_transports, list) {
 991                 if (tt == priv->iscsi_transport) {
 992                         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 993                         return priv;
 994                 }
 995         }
 996         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 997         return NULL;
 998 }
 999
1000 static int
1001 iscsi_multicast_skb(struct sk_buff *skb, uint32_t group, gfp_t gfp)
1002 {
1003         return nlmsg_multicast(nls, skb, 0, group, gfp);
1004 }
1005
1006 int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
1007                    char *data, uint32_t data_size)
1008 {
1009         struct nlmsghdr *nlh;
1010         struct sk_buff *skb;
1011         struct iscsi_uevent *ev;
1012         char *pdu;
1013         struct iscsi_internal *priv;
1014         int len = NLMSG_SPACE(sizeof(*ev) + sizeof(struct iscsi_hdr) +
1015                               data_size);
1016
1017         priv = iscsi_if_transport_lookup(conn->transport);
1018         if (!priv)
1019                 return -EINVAL;
1020
1021         skb = alloc_skb(len, GFP_ATOMIC);
1022         if (!skb) {
1023                 iscsi_conn_error_event(conn, ISCSI_ERR_CONN_FAILED);
1024                 iscsi_cls_conn_printk(KERN_ERR, conn, "can not deliver "
1025                                       "control PDU: OOM\n");
1026                 return -ENOMEM;
1027         }
1028
1029         nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1030         ev = NLMSG_DATA(nlh);
1031         memset(ev, 0, sizeof(*ev));
1032         ev->transport_handle = iscsi_handle(conn->transport);
1033         ev->type = ISCSI_KEVENT_RECV_PDU;
1034         ev->r.recv_req.cid = conn->cid;
1035         ev->r.recv_req.sid = iscsi_conn_get_sid(conn);
1036         pdu = (char*)ev + sizeof(*ev);
1037         memcpy(pdu, hdr, sizeof(struct iscsi_hdr));
1038         memcpy(pdu + sizeof(struct iscsi_hdr), data, data_size);
1039
1040         return iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_ATOMIC);
1041 }
1042 EXPORT_SYMBOL_GPL(iscsi_recv_pdu);
1043
1044 int iscsi_offload_mesg(struct Scsi_Host *shost,
1045                        struct iscsi_transport *transport, uint32_t type,
1046                        char *data, uint16_t data_size)
1047 {
1048         struct nlmsghdr *nlh;
1049         struct sk_buff *skb;
1050         struct iscsi_uevent *ev;
1051         int len = NLMSG_SPACE(sizeof(*ev) + data_size);
1052
1053         skb = alloc_skb(len, GFP_ATOMIC);
1054         if (!skb) {
1055                 printk(KERN_ERR "can not deliver iscsi offload message:OOM\n");
1056                 return -ENOMEM;
1057         }
1058
1059         nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1060         ev = NLMSG_DATA(nlh);
1061         memset(ev, 0, sizeof(*ev));
1062         ev->type = type;
1063         ev->transport_handle = iscsi_handle(transport);
1064         switch (type) {
1065         case ISCSI_KEVENT_PATH_REQ:
1066                 ev->r.req_path.host_no = shost->host_no;
1067                 break;
1068         case ISCSI_KEVENT_IF_DOWN:
1069                 ev->r.notify_if_down.host_no = shost->host_no;
1070                 break;
1071         }
1072
1073         memcpy((char *)ev + sizeof(*ev), data, data_size);
1074
1075         return iscsi_multicast_skb(skb, ISCSI_NL_GRP_UIP, GFP_ATOMIC);
1076 }
1077 EXPORT_SYMBOL_GPL(iscsi_offload_mesg);
1078
1079 void iscsi_conn_error_event(struct iscsi_cls_conn *conn, enum iscsi_err error)
1080 {
1081         struct nlmsghdr *nlh;
1082         struct sk_buff  *skb;
1083         struct iscsi_uevent *ev;
1084         struct iscsi_internal *priv;
1085         int len = NLMSG_SPACE(sizeof(*ev));
1086
1087         priv = iscsi_if_transport_lookup(conn->transport);
1088         if (!priv)
1089                 return;
1090
1091         skb = alloc_skb(len, GFP_ATOMIC);
1092         if (!skb) {
1093                 iscsi_cls_conn_printk(KERN_ERR, conn, "gracefully ignored "
1094                                       "conn error (%d)\n", error);
1095                 return;
1096         }
1097
1098         nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1099         ev = NLMSG_DATA(nlh);
1100         ev->transport_handle = iscsi_handle(conn->transport);
1101         ev->type = ISCSI_KEVENT_CONN_ERROR;
1102         ev->r.connerror.error = error;
1103         ev->r.connerror.cid = conn->cid;
1104         ev->r.connerror.sid = iscsi_conn_get_sid(conn);
1105
1106         iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_ATOMIC);
1107
1108         iscsi_cls_conn_printk(KERN_INFO, conn, "detected conn error (%d)\n",
1109                               error);
1110 }
1111 EXPORT_SYMBOL_GPL(iscsi_conn_error_event);
1112
1113 static int
1114 iscsi_if_send_reply(uint32_t group, int seq, int type, int done, int multi,
1115                     void *payload, int size)
1116 {
1117         struct sk_buff  *skb;
1118         struct nlmsghdr *nlh;
1119         int len = NLMSG_SPACE(size);
1120         int flags = multi ? NLM_F_MULTI : 0;
1121         int t = done ? NLMSG_DONE : type;
1122
1123         skb = alloc_skb(len, GFP_ATOMIC);
1124         if (!skb) {
1125                 printk(KERN_ERR "Could not allocate skb to send reply.\n");
1126                 return -ENOMEM;
1127         }
1128
1129         nlh = __nlmsg_put(skb, 0, 0, t, (len - sizeof(*nlh)), 0);
1130         nlh->nlmsg_flags = flags;
1131         memcpy(NLMSG_DATA(nlh), payload, size);
1132         return iscsi_multicast_skb(skb, group, GFP_ATOMIC);
1133 }
1134
1135 static int
1136 iscsi_if_get_stats(struct iscsi_transport *transport, struct nlmsghdr *nlh)
1137 {
1138         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1139         struct iscsi_stats *stats;
1140         struct sk_buff *skbstat;
1141         struct iscsi_cls_conn *conn;
1142         struct nlmsghdr *nlhstat;
1143         struct iscsi_uevent *evstat;
1144         struct iscsi_internal *priv;
1145         int len = NLMSG_SPACE(sizeof(*ev) +
1146                               sizeof(struct iscsi_stats) +
1147                               sizeof(struct iscsi_stats_custom) *
1148                               ISCSI_STATS_CUSTOM_MAX);
1149         int err = 0;
1150
1151         priv = iscsi_if_transport_lookup(transport);
1152         if (!priv)
1153                 return -EINVAL;
1154
1155         conn = iscsi_conn_lookup(ev->u.get_stats.sid, ev->u.get_stats.cid);
1156         if (!conn)
1157                 return -EEXIST;
1158
1159         do {
1160                 int actual_size;
1161
1162                 skbstat = alloc_skb(len, GFP_ATOMIC);
1163                 if (!skbstat) {
1164                         iscsi_cls_conn_printk(KERN_ERR, conn, "can not "
1165                                               "deliver stats: OOM\n");
1166                         return -ENOMEM;
1167                 }
1168
1169                 nlhstat = __nlmsg_put(skbstat, 0, 0, 0,
1170                                       (len - sizeof(*nlhstat)), 0);
1171                 evstat = NLMSG_DATA(nlhstat);
1172                 memset(evstat, 0, sizeof(*evstat));
1173                 evstat->transport_handle = iscsi_handle(conn->transport);
1174                 evstat->type = nlh->nlmsg_type;
1175                 evstat->u.get_stats.cid =
1176                         ev->u.get_stats.cid;
1177                 evstat->u.get_stats.sid =
1178                         ev->u.get_stats.sid;
1179                 stats = (struct iscsi_stats *)
1180                         ((char*)evstat + sizeof(*evstat));
1181                 memset(stats, 0, sizeof(*stats));
1182
1183                 transport->get_stats(conn, stats);
1184                 actual_size = NLMSG_SPACE(sizeof(struct iscsi_uevent) +
1185                                           sizeof(struct iscsi_stats) +
1186                                           sizeof(struct iscsi_stats_custom) *
1187                                           stats->custom_length);
1188                 actual_size -= sizeof(*nlhstat);
1189                 actual_size = NLMSG_LENGTH(actual_size);
1190                 skb_trim(skbstat, NLMSG_ALIGN(actual_size));
1191                 nlhstat->nlmsg_len = actual_size;
1192
1193                 err = iscsi_multicast_skb(skbstat, ISCSI_NL_GRP_ISCSID,
1194                                           GFP_ATOMIC);
1195         } while (err < 0 && err != -ECONNREFUSED);
1196
1197         return err;
1198 }
1199
1200 /**
1201  * iscsi_session_event - send session destr. completion event
1202  * @session: iscsi class session
1203  * @event: type of event
1204  */
1205 int iscsi_session_event(struct iscsi_cls_session *session,
1206                         enum iscsi_uevent_e event)
1207 {
1208         struct iscsi_internal *priv;
1209         struct Scsi_Host *shost;
1210         struct iscsi_uevent *ev;
1211         struct sk_buff  *skb;
1212         struct nlmsghdr *nlh;
1213         int rc, len = NLMSG_SPACE(sizeof(*ev));
1214
1215         priv = iscsi_if_transport_lookup(session->transport);
1216         if (!priv)
1217                 return -EINVAL;
1218         shost = iscsi_session_to_shost(session);
1219
1220         skb = alloc_skb(len, GFP_KERNEL);
1221         if (!skb) {
1222                 iscsi_cls_session_printk(KERN_ERR, session,
1223                                          "Cannot notify userspace of session "
1224                                          "event %u\n", event);
1225                 return -ENOMEM;
1226         }
1227
1228         nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1229         ev = NLMSG_DATA(nlh);
1230         ev->transport_handle = iscsi_handle(session->transport);
1231
1232         ev->type = event;
1233         switch (event) {
1234         case ISCSI_KEVENT_DESTROY_SESSION:
1235                 ev->r.d_session.host_no = shost->host_no;
1236                 ev->r.d_session.sid = session->sid;
1237                 break;
1238         case ISCSI_KEVENT_CREATE_SESSION:
1239                 ev->r.c_session_ret.host_no = shost->host_no;
1240                 ev->r.c_session_ret.sid = session->sid;
1241                 break;
1242         case ISCSI_KEVENT_UNBIND_SESSION:
1243                 ev->r.unbind_session.host_no = shost->host_no;
1244                 ev->r.unbind_session.sid = session->sid;
1245                 break;
1246         default:
1247                 iscsi_cls_session_printk(KERN_ERR, session, "Invalid event "
1248                                          "%u.\n", event);
1249                 kfree_skb(skb);
1250                 return -EINVAL;
1251         }
1252
1253         /*
1254          * this will occur if the daemon is not up, so we just warn
1255          * the user and when the daemon is restarted it will handle it
1256          */
1257         rc = iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_KERNEL);
1258         if (rc == -ESRCH)
1259                 iscsi_cls_session_printk(KERN_ERR, session,
1260                                          "Cannot notify userspace of session "
1261                                          "event %u. Check iscsi daemon\n",
1262                                          event);
1263
1264         ISCSI_DBG_TRANS_SESSION(session, "Completed handling event %d rc %d\n",
1265                                 event, rc);
1266         return rc;
1267 }
1268 EXPORT_SYMBOL_GPL(iscsi_session_event);
1269
1270 static int
1271 iscsi_if_create_session(struct iscsi_internal *priv, struct iscsi_endpoint *ep,
1272                         struct iscsi_uevent *ev, uint32_t initial_cmdsn,
1273                         uint16_t cmds_max, uint16_t queue_depth)
1274 {
1275         struct iscsi_transport *transport = priv->iscsi_transport;
1276         struct iscsi_cls_session *session;
1277         struct Scsi_Host *shost;
1278
1279         session = transport->create_session(ep, cmds_max, queue_depth,
1280                                             initial_cmdsn);
1281         if (!session)
1282                 return -ENOMEM;
1283
1284         shost = iscsi_session_to_shost(session);
1285         ev->r.c_session_ret.host_no = shost->host_no;
1286         ev->r.c_session_ret.sid = session->sid;
1287         ISCSI_DBG_TRANS_SESSION(session,
1288                                 "Completed creating transport session\n");
1289         return 0;
1290 }
1291
1292 static int
1293 iscsi_if_create_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1294 {
1295         struct iscsi_cls_conn *conn;
1296         struct iscsi_cls_session *session;
1297
1298         session = iscsi_session_lookup(ev->u.c_conn.sid);
1299         if (!session) {
1300                 printk(KERN_ERR "iscsi: invalid session %d.\n",
1301                        ev->u.c_conn.sid);
1302                 return -EINVAL;
1303         }
1304
1305         conn = transport->create_conn(session, ev->u.c_conn.cid);
1306         if (!conn) {
1307                 iscsi_cls_session_printk(KERN_ERR, session,
1308                                          "couldn't create a new connection.");
1309                 return -ENOMEM;
1310         }
1311
1312         ev->r.c_conn_ret.sid = session->sid;
1313         ev->r.c_conn_ret.cid = conn->cid;
1314
1315         ISCSI_DBG_TRANS_CONN(conn, "Completed creating transport conn\n");
1316         return 0;
1317 }
1318
1319 static int
1320 iscsi_if_destroy_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1321 {
1322         struct iscsi_cls_conn *conn;
1323
1324         conn = iscsi_conn_lookup(ev->u.d_conn.sid, ev->u.d_conn.cid);
1325         if (!conn)
1326                 return -EINVAL;
1327
1328         ISCSI_DBG_TRANS_CONN(conn, "Destroying transport conn\n");
1329         if (transport->destroy_conn)
1330                 transport->destroy_conn(conn);
1331
1332         return 0;
1333 }
1334
1335 static int
1336 iscsi_set_param(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1337 {
1338         char *data = (char*)ev + sizeof(*ev);
1339         struct iscsi_cls_conn *conn;
1340         struct iscsi_cls_session *session;
1341         int err = 0, value = 0;
1342
1343         session = iscsi_session_lookup(ev->u.set_param.sid);
1344         conn = iscsi_conn_lookup(ev->u.set_param.sid, ev->u.set_param.cid);
1345         if (!conn || !session)
1346                 return -EINVAL;
1347
1348         switch (ev->u.set_param.param) {
1349         case ISCSI_PARAM_SESS_RECOVERY_TMO:
1350                 sscanf(data, "%d", &value);
1351                 if (value != 0)
1352                         session->recovery_tmo = value;
1353                 break;
1354         default:
1355                 err = transport->set_param(conn, ev->u.set_param.param,
1356                                            data, ev->u.set_param.len);
1357         }
1358
1359         return err;
1360 }
1361
1362 static int iscsi_if_ep_connect(struct iscsi_transport *transport,
1363                                struct iscsi_uevent *ev, int msg_type)
1364 {
1365         struct iscsi_endpoint *ep;
1366         struct sockaddr *dst_addr;
1367         struct Scsi_Host *shost = NULL;
1368         int non_blocking, err = 0;
1369
1370         if (!transport->ep_connect)
1371                 return -EINVAL;
1372
1373         if (msg_type == ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST) {
1374                 shost = scsi_host_lookup(ev->u.ep_connect_through_host.host_no);
1375                 if (!shost) {
1376                         printk(KERN_ERR "ep connect failed. Could not find "
1377                                "host no %u\n",
1378                                ev->u.ep_connect_through_host.host_no);
1379                         return -ENODEV;
1380                 }
1381                 non_blocking = ev->u.ep_connect_through_host.non_blocking;
1382         } else
1383                 non_blocking = ev->u.ep_connect.non_blocking;
1384
1385         dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1386         ep = transport->ep_connect(shost, dst_addr, non_blocking);
1387         if (IS_ERR(ep)) {
1388                 err = PTR_ERR(ep);
1389                 goto release_host;
1390         }
1391
1392         ev->r.ep_connect_ret.handle = ep->id;
1393 release_host:
1394         if (shost)
1395                 scsi_host_put(shost);
1396         return err;
1397 }
1398
1399 static int
1400 iscsi_if_transport_ep(struct iscsi_transport *transport,
1401                       struct iscsi_uevent *ev, int msg_type)
1402 {
1403         struct iscsi_endpoint *ep;
1404         int rc = 0;
1405
1406         switch (msg_type) {
1407         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST:
1408         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1409                 rc = iscsi_if_ep_connect(transport, ev, msg_type);
1410                 break;
1411         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1412                 if (!transport->ep_poll)
1413                         return -EINVAL;
1414
1415                 ep = iscsi_lookup_endpoint(ev->u.ep_poll.ep_handle);
1416                 if (!ep)
1417                         return -EINVAL;
1418
1419                 ev->r.retcode = transport->ep_poll(ep,
1420                                                    ev->u.ep_poll.timeout_ms);
1421                 break;
1422         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1423                 if (!transport->ep_disconnect)
1424                         return -EINVAL;
1425
1426                 ep = iscsi_lookup_endpoint(ev->u.ep_disconnect.ep_handle);
1427                 if (!ep)
1428                         return -EINVAL;
1429
1430                 transport->ep_disconnect(ep);
1431                 break;
1432         }
1433         return rc;
1434 }
1435
1436 static int
1437 iscsi_tgt_dscvr(struct iscsi_transport *transport,
1438                 struct iscsi_uevent *ev)
1439 {
1440         struct Scsi_Host *shost;
1441         struct sockaddr *dst_addr;
1442         int err;
1443
1444         if (!transport->tgt_dscvr)
1445                 return -EINVAL;
1446
1447         shost = scsi_host_lookup(ev->u.tgt_dscvr.host_no);
1448         if (!shost) {
1449                 printk(KERN_ERR "target discovery could not find host no %u\n",
1450                        ev->u.tgt_dscvr.host_no);
1451                 return -ENODEV;
1452         }
1453
1454
1455         dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1456         err = transport->tgt_dscvr(shost, ev->u.tgt_dscvr.type,
1457                                    ev->u.tgt_dscvr.enable, dst_addr);
1458         scsi_host_put(shost);
1459         return err;
1460 }
1461
1462 static int
1463 iscsi_set_host_param(struct iscsi_transport *transport,
1464                      struct iscsi_uevent *ev)
1465 {
1466         char *data = (char*)ev + sizeof(*ev);
1467         struct Scsi_Host *shost;
1468         int err;
1469
1470         if (!transport->set_host_param)
1471                 return -ENOSYS;
1472
1473         shost = scsi_host_lookup(ev->u.set_host_param.host_no);
1474         if (!shost) {
1475                 printk(KERN_ERR "set_host_param could not find host no %u\n",
1476                        ev->u.set_host_param.host_no);
1477                 return -ENODEV;
1478         }
1479
1480         err = transport->set_host_param(shost, ev->u.set_host_param.param,
1481                                         data, ev->u.set_host_param.len);
1482         scsi_host_put(shost);
1483         return err;
1484 }
1485
1486 static int
1487 iscsi_set_path(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1488 {
1489         struct Scsi_Host *shost;
1490         struct iscsi_path *params;
1491         int err;
1492
1493         if (!transport->set_path)
1494                 return -ENOSYS;
1495
1496         shost = scsi_host_lookup(ev->u.set_path.host_no);
1497         if (!shost) {
1498                 printk(KERN_ERR "set path could not find host no %u\n",
1499                        ev->u.set_path.host_no);
1500                 return -ENODEV;
1501         }
1502
1503         params = (struct iscsi_path *)((char *)ev + sizeof(*ev));
1504         err = transport->set_path(shost, params);
1505
1506         scsi_host_put(shost);
1507         return err;
1508 }
1509
1510 static int
1511 iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, uint32_t *group)
1512 {
1513         int err = 0;
1514         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1515         struct iscsi_transport *transport = NULL;
1516         struct iscsi_internal *priv;
1517         struct iscsi_cls_session *session;
1518         struct iscsi_cls_conn *conn;
1519         struct iscsi_endpoint *ep = NULL;
1520
1521         if (nlh->nlmsg_type == ISCSI_UEVENT_PATH_UPDATE)
1522                 *group = ISCSI_NL_GRP_UIP;
1523         else
1524                 *group = ISCSI_NL_GRP_ISCSID;
1525
1526         priv = iscsi_if_transport_lookup(iscsi_ptr(ev->transport_handle));
1527         if (!priv)
1528                 return -EINVAL;
1529         transport = priv->iscsi_transport;
1530
1531         if (!try_module_get(transport->owner))
1532                 return -EINVAL;
1533
1534         switch (nlh->nlmsg_type) {
1535         case ISCSI_UEVENT_CREATE_SESSION:
1536                 err = iscsi_if_create_session(priv, ep, ev,
1537                                               ev->u.c_session.initial_cmdsn,
1538                                               ev->u.c_session.cmds_max,
1539                                               ev->u.c_session.queue_depth);
1540                 break;
1541         case ISCSI_UEVENT_CREATE_BOUND_SESSION:
1542                 ep = iscsi_lookup_endpoint(ev->u.c_bound_session.ep_handle);
1543                 if (!ep) {
1544                         err = -EINVAL;
1545                         break;
1546                 }
1547
1548                 err = iscsi_if_create_session(priv, ep, ev,
1549                                         ev->u.c_bound_session.initial_cmdsn,
1550                                         ev->u.c_bound_session.cmds_max,
1551                                         ev->u.c_bound_session.queue_depth);
1552                 break;
1553         case ISCSI_UEVENT_DESTROY_SESSION:
1554                 session = iscsi_session_lookup(ev->u.d_session.sid);
1555                 if (session)
1556                         transport->destroy_session(session);
1557                 else
1558                         err = -EINVAL;
1559                 break;
1560         case ISCSI_UEVENT_UNBIND_SESSION:
1561                 session = iscsi_session_lookup(ev->u.d_session.sid);
1562                 if (session)
1563                         scsi_queue_work(iscsi_session_to_shost(session),
1564                                         &session->unbind_work);
1565                 else
1566                         err = -EINVAL;
1567                 break;
1568         case ISCSI_UEVENT_CREATE_CONN:
1569                 err = iscsi_if_create_conn(transport, ev);
1570                 break;
1571         case ISCSI_UEVENT_DESTROY_CONN:
1572                 err = iscsi_if_destroy_conn(transport, ev);
1573                 break;
1574         case ISCSI_UEVENT_BIND_CONN:
1575                 session = iscsi_session_lookup(ev->u.b_conn.sid);
1576                 conn = iscsi_conn_lookup(ev->u.b_conn.sid, ev->u.b_conn.cid);
1577
1578                 if (session && conn)
1579                         ev->r.retcode = transport->bind_conn(session, conn,
1580                                         ev->u.b_conn.transport_eph,
1581                                         ev->u.b_conn.is_leading);
1582                 else
1583                         err = -EINVAL;
1584                 break;
1585         case ISCSI_UEVENT_SET_PARAM:
1586                 err = iscsi_set_param(transport, ev);
1587                 break;
1588         case ISCSI_UEVENT_START_CONN:
1589                 conn = iscsi_conn_lookup(ev->u.start_conn.sid, ev->u.start_conn.cid);
1590                 if (conn)
1591                         ev->r.retcode = transport->start_conn(conn);
1592                 else
1593                         err = -EINVAL;
1594                 break;
1595         case ISCSI_UEVENT_STOP_CONN:
1596                 conn = iscsi_conn_lookup(ev->u.stop_conn.sid, ev->u.stop_conn.cid);
1597                 if (conn)
1598                         transport->stop_conn(conn, ev->u.stop_conn.flag);
1599                 else
1600                         err = -EINVAL;
1601                 break;
1602         case ISCSI_UEVENT_SEND_PDU:
1603                 conn = iscsi_conn_lookup(ev->u.send_pdu.sid, ev->u.send_pdu.cid);
1604                 if (conn)
1605                         ev->r.retcode = transport->send_pdu(conn,
1606                                 (struct iscsi_hdr*)((char*)ev + sizeof(*ev)),
1607                                 (char*)ev + sizeof(*ev) + ev->u.send_pdu.hdr_size,
1608                                 ev->u.send_pdu.data_size);
1609                 else
1610                         err = -EINVAL;
1611                 break;
1612         case ISCSI_UEVENT_GET_STATS:
1613                 err = iscsi_if_get_stats(transport, nlh);
1614                 break;
1615         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1616         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1617         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1618         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST:
1619                 err = iscsi_if_transport_ep(transport, ev, nlh->nlmsg_type);
1620                 break;
1621         case ISCSI_UEVENT_TGT_DSCVR:
1622                 err = iscsi_tgt_dscvr(transport, ev);
1623                 break;
1624         case ISCSI_UEVENT_SET_HOST_PARAM:
1625                 err = iscsi_set_host_param(transport, ev);
1626                 break;
1627         case ISCSI_UEVENT_PATH_UPDATE:
1628                 err = iscsi_set_path(transport, ev);
1629                 break;
1630         default:
1631                 err = -ENOSYS;
1632                 break;
1633         }
1634
1635         module_put(transport->owner);
1636         return err;
1637 }
1638
1639 /*
1640  * Get message from skb.  Each message is processed by iscsi_if_recv_msg.
1641  * Malformed skbs with wrong lengths or invalid creds are not processed.
1642  */
1643 static void
1644 iscsi_if_rx(struct sk_buff *skb)
1645 {
1646         mutex_lock(&rx_queue_mutex);
1647         while (skb->len >= NLMSG_SPACE(0)) {
1648                 int err;
1649                 uint32_t rlen;
1650                 struct nlmsghdr *nlh;
1651                 struct iscsi_uevent *ev;
1652                 uint32_t group;
1653
1654                 nlh = nlmsg_hdr(skb);
1655                 if (nlh->nlmsg_len < sizeof(*nlh) ||
1656                     skb->len < nlh->nlmsg_len) {
1657                         break;
1658                 }
1659
1660                 ev = NLMSG_DATA(nlh);
1661                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1662                 if (rlen > skb->len)
1663                         rlen = skb->len;
1664
1665                 err = iscsi_if_recv_msg(skb, nlh, &group);
1666                 if (err) {
1667                         ev->type = ISCSI_KEVENT_IF_ERROR;
1668                         ev->iferror = err;
1669                 }
1670                 do {
1671                         /*
1672                          * special case for GET_STATS:
1673                          * on success - sending reply and stats from
1674                          * inside of if_recv_msg(),
1675                          * on error - fall through.
1676                          */
1677                         if (ev->type == ISCSI_UEVENT_GET_STATS && !err)
1678                                 break;
1679                         err = iscsi_if_send_reply(group, nlh->nlmsg_seq,
1680                                 nlh->nlmsg_type, 0, 0, ev, sizeof(*ev));
1681                 } while (err < 0 && err != -ECONNREFUSED);
1682                 skb_pull(skb, rlen);
1683         }
1684         mutex_unlock(&rx_queue_mutex);
1685 }
1686
1687 #define ISCSI_CLASS_ATTR(_prefix,_name,_mode,_show,_store)              \
1688 struct device_attribute dev_attr_##_prefix##_##_name =  \
1689         __ATTR(_name,_mode,_show,_store)
1690
1691 /*
1692  * iSCSI connection attrs
1693  */
1694 #define iscsi_conn_attr_show(param)                                     \
1695 static ssize_t                                                          \
1696 show_conn_param_##param(struct device *dev,                             \
1697                         struct device_attribute *attr, char *buf)       \
1698 {                                                                       \
1699         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev->parent);   \
1700         struct iscsi_transport *t = conn->transport;                    \
1701         return t->get_conn_param(conn, param, buf);                     \
1702 }
1703
1704 #define iscsi_conn_attr(field, param)                                   \
1705         iscsi_conn_attr_show(param)                                     \
1706 static ISCSI_CLASS_ATTR(conn, field, S_IRUGO, show_conn_param_##param,  \
1707                         NULL);
1708
1709 iscsi_conn_attr(max_recv_dlength, ISCSI_PARAM_MAX_RECV_DLENGTH);
1710 iscsi_conn_attr(max_xmit_dlength, ISCSI_PARAM_MAX_XMIT_DLENGTH);
1711 iscsi_conn_attr(header_digest, ISCSI_PARAM_HDRDGST_EN);
1712 iscsi_conn_attr(data_digest, ISCSI_PARAM_DATADGST_EN);
1713 iscsi_conn_attr(ifmarker, ISCSI_PARAM_IFMARKER_EN);
1714 iscsi_conn_attr(ofmarker, ISCSI_PARAM_OFMARKER_EN);
1715 iscsi_conn_attr(persistent_port, ISCSI_PARAM_PERSISTENT_PORT);
1716 iscsi_conn_attr(port, ISCSI_PARAM_CONN_PORT);
1717 iscsi_conn_attr(exp_statsn, ISCSI_PARAM_EXP_STATSN);
1718 iscsi_conn_attr(persistent_address, ISCSI_PARAM_PERSISTENT_ADDRESS);
1719 iscsi_conn_attr(address, ISCSI_PARAM_CONN_ADDRESS);
1720 iscsi_conn_attr(ping_tmo, ISCSI_PARAM_PING_TMO);
1721 iscsi_conn_attr(recv_tmo, ISCSI_PARAM_RECV_TMO);
1722
1723 /*
1724  * iSCSI session attrs
1725  */
1726 #define iscsi_session_attr_show(param, perm)                            \
1727 static ssize_t                                                          \
1728 show_session_param_##param(struct device *dev,                          \
1729                            struct device_attribute *attr, char *buf)    \
1730 {                                                                       \
1731         struct iscsi_cls_session *session =                             \
1732                 iscsi_dev_to_session(dev->parent);                      \
1733         struct iscsi_transport *t = session->transport;                 \
1734                                                                         \
1735         if (perm && !capable(CAP_SYS_ADMIN))                            \
1736                 return -EACCES;                                         \
1737         return t->get_session_param(session, param, buf);               \
1738 }
1739
1740 #define iscsi_session_attr(field, param, perm)                          \
1741         iscsi_session_attr_show(param, perm)                            \
1742 static ISCSI_CLASS_ATTR(sess, field, S_IRUGO, show_session_param_##param, \
1743                         NULL);
1744
1745 iscsi_session_attr(targetname, ISCSI_PARAM_TARGET_NAME, 0);
1746 iscsi_session_attr(initial_r2t, ISCSI_PARAM_INITIAL_R2T_EN, 0);
1747 iscsi_session_attr(max_outstanding_r2t, ISCSI_PARAM_MAX_R2T, 0);
1748 iscsi_session_attr(immediate_data, ISCSI_PARAM_IMM_DATA_EN, 0);
1749 iscsi_session_attr(first_burst_len, ISCSI_PARAM_FIRST_BURST, 0);
1750 iscsi_session_attr(max_burst_len, ISCSI_PARAM_MAX_BURST, 0);
1751 iscsi_session_attr(data_pdu_in_order, ISCSI_PARAM_PDU_INORDER_EN, 0);
1752 iscsi_session_attr(data_seq_in_order, ISCSI_PARAM_DATASEQ_INORDER_EN, 0);
1753 iscsi_session_attr(erl, ISCSI_PARAM_ERL, 0);
1754 iscsi_session_attr(tpgt, ISCSI_PARAM_TPGT, 0);
1755 iscsi_session_attr(username, ISCSI_PARAM_USERNAME, 1);
1756 iscsi_session_attr(username_in, ISCSI_PARAM_USERNAME_IN, 1);
1757 iscsi_session_attr(password, ISCSI_PARAM_PASSWORD, 1);
1758 iscsi_session_attr(password_in, ISCSI_PARAM_PASSWORD_IN, 1);
1759 iscsi_session_attr(fast_abort, ISCSI_PARAM_FAST_ABORT, 0);
1760 iscsi_session_attr(abort_tmo, ISCSI_PARAM_ABORT_TMO, 0);
1761 iscsi_session_attr(lu_reset_tmo, ISCSI_PARAM_LU_RESET_TMO, 0);
1762 iscsi_session_attr(ifacename, ISCSI_PARAM_IFACE_NAME, 0);
1763 iscsi_session_attr(initiatorname, ISCSI_PARAM_INITIATOR_NAME, 0)
1764
1765 static ssize_t
1766 show_priv_session_state(struct device *dev, struct device_attribute *attr,
1767                         char *buf)
1768 {
1769         struct iscsi_cls_session *session = iscsi_dev_to_session(dev->parent);
1770         return sprintf(buf, "%s\n", iscsi_session_state_name(session->state));
1771 }
1772 static ISCSI_CLASS_ATTR(priv_sess, state, S_IRUGO, show_priv_session_state,
1773                         NULL);
1774
1775 #define iscsi_priv_session_attr_show(field, format)                     \
1776 static ssize_t                                                          \
1777 show_priv_session_##field(struct device *dev,                           \
1778                           struct device_attribute *attr, char *buf)     \
1779 {                                                                       \
1780         struct iscsi_cls_session *session =                             \
1781                         iscsi_dev_to_session(dev->parent);              \
1782         return sprintf(buf, format"\n", session->field);                \
1783 }
1784
1785 #define iscsi_priv_session_attr(field, format)                          \
1786         iscsi_priv_session_attr_show(field, format)                     \
1787 static ISCSI_CLASS_ATTR(priv_sess, field, S_IRUGO, show_priv_session_##field, \
1788                         NULL)
1789 iscsi_priv_session_attr(recovery_tmo, "%d");
1790
1791 /*
1792  * iSCSI host attrs
1793  */
1794 #define iscsi_host_attr_show(param)                                     \
1795 static ssize_t                                                          \
1796 show_host_param_##param(struct device *dev,                             \
1797                         struct device_attribute *attr, char *buf)       \
1798 {                                                                       \
1799         struct Scsi_Host *shost = transport_class_to_shost(dev);        \
1800         struct iscsi_internal *priv = to_iscsi_internal(shost->transportt); \
1801         return priv->iscsi_transport->get_host_param(shost, param, buf); \
1802 }
1803
1804 #define iscsi_host_attr(field, param)                                   \
1805         iscsi_host_attr_show(param)                                     \
1806 static ISCSI_CLASS_ATTR(host, field, S_IRUGO, show_host_param_##param,  \
1807                         NULL);
1808
1809 iscsi_host_attr(netdev, ISCSI_HOST_PARAM_NETDEV_NAME);
1810 iscsi_host_attr(hwaddress, ISCSI_HOST_PARAM_HWADDRESS);
1811 iscsi_host_attr(ipaddress, ISCSI_HOST_PARAM_IPADDRESS);
1812 iscsi_host_attr(initiatorname, ISCSI_HOST_PARAM_INITIATOR_NAME);
1813
1814 #define SETUP_PRIV_SESSION_RD_ATTR(field)                               \
1815 do {                                                                    \
1816         priv->session_attrs[count] = &dev_attr_priv_sess_##field; \
1817         count++;                                                        \
1818 } while (0)
1819
1820
1821 #define SETUP_SESSION_RD_ATTR(field, param_flag)                        \
1822 do {                                                                    \
1823         if (tt->param_mask & param_flag) {                              \
1824                 priv->session_attrs[count] = &dev_attr_sess_##field; \
1825                 count++;                                                \
1826         }                                                               \
1827 } while (0)
1828
1829 #define SETUP_CONN_RD_ATTR(field, param_flag)                           \
1830 do {                                                                    \
1831         if (tt->param_mask & param_flag) {                              \
1832                 priv->conn_attrs[count] = &dev_attr_conn_##field; \
1833                 count++;                                                \
1834         }                                                               \
1835 } while (0)
1836
1837 #define SETUP_HOST_RD_ATTR(field, param_flag)                           \
1838 do {                                                                    \
1839         if (tt->host_param_mask & param_flag) {                         \
1840                 priv->host_attrs[count] = &dev_attr_host_##field; \
1841                 count++;                                                \
1842         }                                                               \
1843 } while (0)
1844
1845 static int iscsi_session_match(struct attribute_container *cont,
1846                            struct device *dev)
1847 {
1848         struct iscsi_cls_session *session;
1849         struct Scsi_Host *shost;
1850         struct iscsi_internal *priv;
1851
1852         if (!iscsi_is_session_dev(dev))
1853                 return 0;
1854
1855         session = iscsi_dev_to_session(dev);
1856         shost = iscsi_session_to_shost(session);
1857         if (!shost->transportt)
1858                 return 0;
1859
1860         priv = to_iscsi_internal(shost->transportt);
1861         if (priv->session_cont.ac.class != &iscsi_session_class.class)
1862                 return 0;
1863
1864         return &priv->session_cont.ac == cont;
1865 }
1866
1867 static int iscsi_conn_match(struct attribute_container *cont,
1868                            struct device *dev)
1869 {
1870         struct iscsi_cls_session *session;
1871         struct iscsi_cls_conn *conn;
1872         struct Scsi_Host *shost;
1873         struct iscsi_internal *priv;
1874
1875         if (!iscsi_is_conn_dev(dev))
1876                 return 0;
1877
1878         conn = iscsi_dev_to_conn(dev);
1879         session = iscsi_dev_to_session(conn->dev.parent);
1880         shost = iscsi_session_to_shost(session);
1881
1882         if (!shost->transportt)
1883                 return 0;
1884
1885         priv = to_iscsi_internal(shost->transportt);
1886         if (priv->conn_cont.ac.class != &iscsi_connection_class.class)
1887                 return 0;
1888
1889         return &priv->conn_cont.ac == cont;
1890 }
1891
1892 static int iscsi_host_match(struct attribute_container *cont,
1893                             struct device *dev)
1894 {
1895         struct Scsi_Host *shost;
1896         struct iscsi_internal *priv;
1897
1898         if (!scsi_is_host_device(dev))
1899                 return 0;
1900
1901         shost = dev_to_shost(dev);
1902         if (!shost->transportt  ||
1903             shost->transportt->host_attrs.ac.class != &iscsi_host_class.class)
1904                 return 0;
1905
1906         priv = to_iscsi_internal(shost->transportt);
1907         return &priv->t.host_attrs.ac == cont;
1908 }
1909
1910 struct scsi_transport_template *
1911 iscsi_register_transport(struct iscsi_transport *tt)
1912 {
1913         struct iscsi_internal *priv;
1914         unsigned long flags;
1915         int count = 0, err;
1916
1917         BUG_ON(!tt);
1918
1919         priv = iscsi_if_transport_lookup(tt);
1920         if (priv)
1921                 return NULL;
1922
1923         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1924         if (!priv)
1925                 return NULL;
1926         INIT_LIST_HEAD(&priv->list);
1927         priv->iscsi_transport = tt;
1928         priv->t.user_scan = iscsi_user_scan;
1929         priv->t.create_work_queue = 1;
1930
1931         priv->dev.class = &iscsi_transport_class;
1932         dev_set_name(&priv->dev, "%s", tt->name);
1933         err = device_register(&priv->dev);
1934         if (err)
1935                 goto free_priv;
1936
1937         err = sysfs_create_group(&priv->dev.kobj, &iscsi_transport_group);
1938         if (err)
1939                 goto unregister_dev;
1940
1941         /* host parameters */
1942         priv->t.host_attrs.ac.attrs = &priv->host_attrs[0];
1943         priv->t.host_attrs.ac.class = &iscsi_host_class.class;
1944         priv->t.host_attrs.ac.match = iscsi_host_match;
1945         priv->t.host_size = sizeof(struct iscsi_cls_host);
1946         transport_container_register(&priv->t.host_attrs);
1947
1948         SETUP_HOST_RD_ATTR(netdev, ISCSI_HOST_NETDEV_NAME);
1949         SETUP_HOST_RD_ATTR(ipaddress, ISCSI_HOST_IPADDRESS);
1950         SETUP_HOST_RD_ATTR(hwaddress, ISCSI_HOST_HWADDRESS);
1951         SETUP_HOST_RD_ATTR(initiatorname, ISCSI_HOST_INITIATOR_NAME);
1952         BUG_ON(count > ISCSI_HOST_ATTRS);
1953         priv->host_attrs[count] = NULL;
1954         count = 0;
1955
1956         /* connection parameters */
1957         priv->conn_cont.ac.attrs = &priv->conn_attrs[0];
1958         priv->conn_cont.ac.class = &iscsi_connection_class.class;
1959         priv->conn_cont.ac.match = iscsi_conn_match;
1960         transport_container_register(&priv->conn_cont);
1961
1962         SETUP_CONN_RD_ATTR(max_recv_dlength, ISCSI_MAX_RECV_DLENGTH);
1963         SETUP_CONN_RD_ATTR(max_xmit_dlength, ISCSI_MAX_XMIT_DLENGTH);
1964         SETUP_CONN_RD_ATTR(header_digest, ISCSI_HDRDGST_EN);
1965         SETUP_CONN_RD_ATTR(data_digest, ISCSI_DATADGST_EN);
1966         SETUP_CONN_RD_ATTR(ifmarker, ISCSI_IFMARKER_EN);
1967         SETUP_CONN_RD_ATTR(ofmarker, ISCSI_OFMARKER_EN);
1968         SETUP_CONN_RD_ATTR(address, ISCSI_CONN_ADDRESS);
1969         SETUP_CONN_RD_ATTR(port, ISCSI_CONN_PORT);
1970         SETUP_CONN_RD_ATTR(exp_statsn, ISCSI_EXP_STATSN);
1971         SETUP_CONN_RD_ATTR(persistent_address, ISCSI_PERSISTENT_ADDRESS);
1972         SETUP_CONN_RD_ATTR(persistent_port, ISCSI_PERSISTENT_PORT);
1973         SETUP_CONN_RD_ATTR(ping_tmo, ISCSI_PING_TMO);
1974         SETUP_CONN_RD_ATTR(recv_tmo, ISCSI_RECV_TMO);
1975
1976         BUG_ON(count > ISCSI_CONN_ATTRS);
1977         priv->conn_attrs[count] = NULL;
1978         count = 0;
1979
1980         /* session parameters */
1981         priv->session_cont.ac.attrs = &priv->session_attrs[0];
1982         priv->session_cont.ac.class = &iscsi_session_class.class;
1983         priv->session_cont.ac.match = iscsi_session_match;
1984         transport_container_register(&priv->session_cont);
1985
1986         SETUP_SESSION_RD_ATTR(initial_r2t, ISCSI_INITIAL_R2T_EN);
1987         SETUP_SESSION_RD_ATTR(max_outstanding_r2t, ISCSI_MAX_R2T);
1988         SETUP_SESSION_RD_ATTR(immediate_data, ISCSI_IMM_DATA_EN);
1989         SETUP_SESSION_RD_ATTR(first_burst_len, ISCSI_FIRST_BURST);
1990         SETUP_SESSION_RD_ATTR(max_burst_len, ISCSI_MAX_BURST);
1991         SETUP_SESSION_RD_ATTR(data_pdu_in_order, ISCSI_PDU_INORDER_EN);
1992         SETUP_SESSION_RD_ATTR(data_seq_in_order, ISCSI_DATASEQ_INORDER_EN);
1993         SETUP_SESSION_RD_ATTR(erl, ISCSI_ERL);
1994         SETUP_SESSION_RD_ATTR(targetname, ISCSI_TARGET_NAME);
1995         SETUP_SESSION_RD_ATTR(tpgt, ISCSI_TPGT);
1996         SETUP_SESSION_RD_ATTR(password, ISCSI_USERNAME);
1997         SETUP_SESSION_RD_ATTR(password_in, ISCSI_USERNAME_IN);
1998         SETUP_SESSION_RD_ATTR(username, ISCSI_PASSWORD);
1999         SETUP_SESSION_RD_ATTR(username_in, ISCSI_PASSWORD_IN);
2000         SETUP_SESSION_RD_ATTR(fast_abort, ISCSI_FAST_ABORT);
2001         SETUP_SESSION_RD_ATTR(abort_tmo, ISCSI_ABORT_TMO);
2002         SETUP_SESSION_RD_ATTR(lu_reset_tmo,ISCSI_LU_RESET_TMO);
2003         SETUP_SESSION_RD_ATTR(ifacename, ISCSI_IFACE_NAME);
2004         SETUP_SESSION_RD_ATTR(initiatorname, ISCSI_INITIATOR_NAME);
2005         SETUP_PRIV_SESSION_RD_ATTR(recovery_tmo);
2006         SETUP_PRIV_SESSION_RD_ATTR(state);
2007
2008         BUG_ON(count > ISCSI_SESSION_ATTRS);
2009         priv->session_attrs[count] = NULL;
2010
2011         spin_lock_irqsave(&iscsi_transport_lock, flags);
2012         list_add(&priv->list, &iscsi_transports);
2013         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
2014
2015         printk(KERN_NOTICE "iscsi: registered transport (%s)\n", tt->name);
2016         return &priv->t;
2017
2018 unregister_dev:
2019         device_unregister(&priv->dev);
2020         return NULL;
2021 free_priv:
2022         kfree(priv);
2023         return NULL;
2024 }
2025 EXPORT_SYMBOL_GPL(iscsi_register_transport);
2026
2027 int iscsi_unregister_transport(struct iscsi_transport *tt)
2028 {
2029         struct iscsi_internal *priv;
2030         unsigned long flags;
2031
2032         BUG_ON(!tt);
2033
2034         mutex_lock(&rx_queue_mutex);
2035
2036         priv = iscsi_if_transport_lookup(tt);
2037         BUG_ON (!priv);
2038
2039         spin_lock_irqsave(&iscsi_transport_lock, flags);
2040         list_del(&priv->list);
2041         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
2042
2043         transport_container_unregister(&priv->conn_cont);
2044         transport_container_unregister(&priv->session_cont);
2045         transport_container_unregister(&priv->t.host_attrs);
2046
2047         sysfs_remove_group(&priv->dev.kobj, &iscsi_transport_group);
2048         device_unregister(&priv->dev);
2049         mutex_unlock(&rx_queue_mutex);
2050
2051         return 0;
2052 }
2053 EXPORT_SYMBOL_GPL(iscsi_unregister_transport);
2054
2055 static __init int iscsi_transport_init(void)
2056 {
2057         int err;
2058
2059         printk(KERN_INFO "Loading iSCSI transport class v%s.\n",
2060                 ISCSI_TRANSPORT_VERSION);
2061
2062         atomic_set(&iscsi_session_nr, 0);
2063
2064         err = class_register(&iscsi_transport_class);
2065         if (err)
2066                 return err;
2067
2068         err = class_register(&iscsi_endpoint_class);
2069         if (err)
2070                 goto unregister_transport_class;
2071
2072         err = transport_class_register(&iscsi_host_class);
2073         if (err)
2074                 goto unregister_endpoint_class;
2075
2076         err = transport_class_register(&iscsi_connection_class);
2077         if (err)
2078                 goto unregister_host_class;
2079
2080         err = transport_class_register(&iscsi_session_class);
2081         if (err)
2082                 goto unregister_conn_class;
2083
2084         nls = netlink_kernel_create(&init_net, NETLINK_ISCSI, 1, iscsi_if_rx,
2085                                     NULL, THIS_MODULE);
2086         if (!nls) {
2087                 err = -ENOBUFS;
2088                 goto unregister_session_class;
2089         }
2090
2091         iscsi_eh_timer_workq = create_singlethread_workqueue("iscsi_eh");
2092         if (!iscsi_eh_timer_workq)
2093                 goto release_nls;
2094
2095         return 0;
2096
2097 release_nls:
2098         netlink_kernel_release(nls);
2099 unregister_session_class:
2100         transport_class_unregister(&iscsi_session_class);
2101 unregister_conn_class:
2102         transport_class_unregister(&iscsi_connection_class);
2103 unregister_host_class:
2104         transport_class_unregister(&iscsi_host_class);
2105 unregister_endpoint_class:
2106         class_unregister(&iscsi_endpoint_class);
2107 unregister_transport_class:
2108         class_unregister(&iscsi_transport_class);
2109         return err;
2110 }
2111
2112 static void __exit iscsi_transport_exit(void)
2113 {
2114         destroy_workqueue(iscsi_eh_timer_workq);
2115         netlink_kernel_release(nls);
2116         transport_class_unregister(&iscsi_connection_class);
2117         transport_class_unregister(&iscsi_session_class);
2118         transport_class_unregister(&iscsi_host_class);
2119         class_unregister(&iscsi_endpoint_class);
2120         class_unregister(&iscsi_transport_class);
2121 }
2122
2123 module_init(iscsi_transport_init);
2124 module_exit(iscsi_transport_exit);
2125
2126 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
2127               "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
2128               "Alex Aizman <itn780@yahoo.com>");
2129 MODULE_DESCRIPTION("iSCSI Transport Interface");
2130 MODULE_LICENSE("GPL");
2131 MODULE_VERSION(ISCSI_TRANSPORT_VERSION);