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 22
  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         if (session->recovery_tmo >= 0)
 631                 queue_delayed_work(iscsi_eh_timer_workq,
 632                                    &session->recovery_work,
 633                                    session->recovery_tmo * HZ);
 634 }
 635
 636 void iscsi_block_session(struct iscsi_cls_session *session)
 637 {
 638         queue_work(iscsi_eh_timer_workq, &session->block_work);
 639 }
 640 EXPORT_SYMBOL_GPL(iscsi_block_session);
 641
 642 static void __iscsi_unbind_session(struct work_struct *work)
 643 {
 644         struct iscsi_cls_session *session =
 645                         container_of(work, struct iscsi_cls_session,
 646                                      unbind_work);
 647         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 648         struct iscsi_cls_host *ihost = shost->shost_data;
 649         unsigned long flags;
 650
 651         ISCSI_DBG_TRANS_SESSION(session, "Unbinding session\n");
 652
 653         /* Prevent new scans and make sure scanning is not in progress */
 654         mutex_lock(&ihost->mutex);
 655         spin_lock_irqsave(&session->lock, flags);
 656         if (session->target_id == ISCSI_MAX_TARGET) {
 657                 spin_unlock_irqrestore(&session->lock, flags);
 658                 mutex_unlock(&ihost->mutex);
 659                 return;
 660         }
 661         session->target_id = ISCSI_MAX_TARGET;
 662         spin_unlock_irqrestore(&session->lock, flags);
 663         mutex_unlock(&ihost->mutex);
 664
 665         scsi_remove_target(&session->dev);
 666         iscsi_session_event(session, ISCSI_KEVENT_UNBIND_SESSION);
 667         ISCSI_DBG_TRANS_SESSION(session, "Completed target removal\n");
 668 }
 669
 670 struct iscsi_cls_session *
 671 iscsi_alloc_session(struct Scsi_Host *shost, struct iscsi_transport *transport,
 672                     int dd_size)
 673 {
 674         struct iscsi_cls_session *session;
 675
 676         session = kzalloc(sizeof(*session) + dd_size,
 677                           GFP_KERNEL);
 678         if (!session)
 679                 return NULL;
 680
 681         session->transport = transport;
 682         session->recovery_tmo = 120;
 683         session->state = ISCSI_SESSION_FREE;
 684         INIT_DELAYED_WORK(&session->recovery_work, session_recovery_timedout);
 685         INIT_LIST_HEAD(&session->sess_list);
 686         INIT_WORK(&session->unblock_work, __iscsi_unblock_session);
 687         INIT_WORK(&session->block_work, __iscsi_block_session);
 688         INIT_WORK(&session->unbind_work, __iscsi_unbind_session);
 689         INIT_WORK(&session->scan_work, iscsi_scan_session);
 690         spin_lock_init(&session->lock);
 691
 692         /* this is released in the dev's release function */
 693         scsi_host_get(shost);
 694         session->dev.parent = &shost->shost_gendev;
 695         session->dev.release = iscsi_session_release;
 696         device_initialize(&session->dev);
 697         if (dd_size)
 698                 session->dd_data = &session[1];
 699
 700         ISCSI_DBG_TRANS_SESSION(session, "Completed session allocation\n");
 701         return session;
 702 }
 703 EXPORT_SYMBOL_GPL(iscsi_alloc_session);
 704
 705 static int iscsi_get_next_target_id(struct device *dev, void *data)
 706 {
 707         struct iscsi_cls_session *session;
 708         unsigned long flags;
 709         int err = 0;
 710
 711         if (!iscsi_is_session_dev(dev))
 712                 return 0;
 713
 714         session = iscsi_dev_to_session(dev);
 715         spin_lock_irqsave(&session->lock, flags);
 716         if (*((unsigned int *) data) == session->target_id)
 717                 err = -EEXIST;
 718         spin_unlock_irqrestore(&session->lock, flags);
 719         return err;
 720 }
 721
 722 int iscsi_add_session(struct iscsi_cls_session *session, unsigned int target_id)
 723 {
 724         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 725         struct iscsi_cls_host *ihost;
 726         unsigned long flags;
 727         unsigned int id = target_id;
 728         int err;
 729
 730         ihost = shost->shost_data;
 731         session->sid = atomic_add_return(1, &iscsi_session_nr);
 732
 733         if (id == ISCSI_MAX_TARGET) {
 734                 for (id = 0; id < ISCSI_MAX_TARGET; id++) {
 735                         err = device_for_each_child(&shost->shost_gendev, &id,
 736                                                     iscsi_get_next_target_id);
 737                         if (!err)
 738                                 break;
 739                 }
 740
 741                 if (id == ISCSI_MAX_TARGET) {
 742                         iscsi_cls_session_printk(KERN_ERR, session,
 743                                                  "Too many iscsi targets. Max "
 744                                                  "number of targets is %d.\n",
 745                                                  ISCSI_MAX_TARGET - 1);
 746                         err = -EOVERFLOW;
 747                         goto release_host;
 748                 }
 749         }
 750         session->target_id = id;
 751
 752         dev_set_name(&session->dev, "session%u", session->sid);
 753         err = device_add(&session->dev);
 754         if (err) {
 755                 iscsi_cls_session_printk(KERN_ERR, session,
 756                                          "could not register session's dev\n");
 757                 goto release_host;
 758         }
 759         transport_register_device(&session->dev);
 760
 761         spin_lock_irqsave(&sesslock, flags);
 762         list_add(&session->sess_list, &sesslist);
 763         spin_unlock_irqrestore(&sesslock, flags);
 764
 765         iscsi_session_event(session, ISCSI_KEVENT_CREATE_SESSION);
 766         ISCSI_DBG_TRANS_SESSION(session, "Completed session adding\n");
 767         return 0;
 768
 769 release_host:
 770         scsi_host_put(shost);
 771         return err;
 772 }
 773 EXPORT_SYMBOL_GPL(iscsi_add_session);
 774
 775 /**
 776  * iscsi_create_session - create iscsi class session
 777  * @shost: scsi host
 778  * @transport: iscsi transport
 779  * @dd_size: private driver data size
 780  * @target_id: which target
 781  *
 782  * This can be called from a LLD or iscsi_transport.
 783  */
 784 struct iscsi_cls_session *
 785 iscsi_create_session(struct Scsi_Host *shost, struct iscsi_transport *transport,
 786                      int dd_size, unsigned int target_id)
 787 {
 788         struct iscsi_cls_session *session;
 789
 790         session = iscsi_alloc_session(shost, transport, dd_size);
 791         if (!session)
 792                 return NULL;
 793
 794         if (iscsi_add_session(session, target_id)) {
 795                 iscsi_free_session(session);
 796                 return NULL;
 797         }
 798         return session;
 799 }
 800 EXPORT_SYMBOL_GPL(iscsi_create_session);
 801
 802 static void iscsi_conn_release(struct device *dev)
 803 {
 804         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev);
 805         struct device *parent = conn->dev.parent;
 806
 807         ISCSI_DBG_TRANS_CONN(conn, "Releasing conn\n");
 808         kfree(conn);
 809         put_device(parent);
 810 }
 811
 812 static int iscsi_is_conn_dev(const struct device *dev)
 813 {
 814         return dev->release == iscsi_conn_release;
 815 }
 816
 817 static int iscsi_iter_destroy_conn_fn(struct device *dev, void *data)
 818 {
 819         if (!iscsi_is_conn_dev(dev))
 820                 return 0;
 821         return iscsi_destroy_conn(iscsi_dev_to_conn(dev));
 822 }
 823
 824 void iscsi_remove_session(struct iscsi_cls_session *session)
 825 {
 826         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 827         unsigned long flags;
 828         int err;
 829
 830         ISCSI_DBG_TRANS_SESSION(session, "Removing session\n");
 831
 832         spin_lock_irqsave(&sesslock, flags);
 833         list_del(&session->sess_list);
 834         spin_unlock_irqrestore(&sesslock, flags);
 835
 836         /* make sure there are no blocks/unblocks queued */
 837         flush_workqueue(iscsi_eh_timer_workq);
 838         /* make sure the timedout callout is not running */
 839         if (!cancel_delayed_work(&session->recovery_work))
 840                 flush_workqueue(iscsi_eh_timer_workq);
 841         /*
 842          * If we are blocked let commands flow again. The lld or iscsi
 843          * layer should set up the queuecommand to fail commands.
 844          * We assume that LLD will not be calling block/unblock while
 845          * removing the session.
 846          */
 847         spin_lock_irqsave(&session->lock, flags);
 848         session->state = ISCSI_SESSION_FREE;
 849         spin_unlock_irqrestore(&session->lock, flags);
 850
 851         scsi_target_unblock(&session->dev);
 852         /* flush running scans then delete devices */
 853         scsi_flush_work(shost);
 854         __iscsi_unbind_session(&session->unbind_work);
 855
 856         /* hw iscsi may not have removed all connections from session */
 857         err = device_for_each_child(&session->dev, NULL,
 858                                     iscsi_iter_destroy_conn_fn);
 859         if (err)
 860                 iscsi_cls_session_printk(KERN_ERR, session,
 861                                          "Could not delete all connections "
 862                                          "for session. Error %d.\n", err);
 863
 864         transport_unregister_device(&session->dev);
 865
 866         ISCSI_DBG_TRANS_SESSION(session, "Completing session removal\n");
 867         device_del(&session->dev);
 868 }
 869 EXPORT_SYMBOL_GPL(iscsi_remove_session);
 870
 871 void iscsi_free_session(struct iscsi_cls_session *session)
 872 {
 873         ISCSI_DBG_TRANS_SESSION(session, "Freeing session\n");
 874         iscsi_session_event(session, ISCSI_KEVENT_DESTROY_SESSION);
 875         put_device(&session->dev);
 876 }
 877 EXPORT_SYMBOL_GPL(iscsi_free_session);
 878
 879 /**
 880  * iscsi_destroy_session - destroy iscsi session
 881  * @session: iscsi_session
 882  *
 883  * Can be called by a LLD or iscsi_transport. There must not be
 884  * any running connections.
 885  */
 886 int iscsi_destroy_session(struct iscsi_cls_session *session)
 887 {
 888         iscsi_remove_session(session);
 889         ISCSI_DBG_TRANS_SESSION(session, "Completing session destruction\n");
 890         iscsi_free_session(session);
 891         return 0;
 892 }
 893 EXPORT_SYMBOL_GPL(iscsi_destroy_session);
 894
 895 /**
 896  * iscsi_create_conn - create iscsi class connection
 897  * @session: iscsi cls session
 898  * @dd_size: private driver data size
 899  * @cid: connection id
 900  *
 901  * This can be called from a LLD or iscsi_transport. The connection
 902  * is child of the session so cid must be unique for all connections
 903  * on the session.
 904  *
 905  * Since we do not support MCS, cid will normally be zero. In some cases
 906  * for software iscsi we could be trying to preallocate a connection struct
 907  * in which case there could be two connection structs and cid would be
 908  * non-zero.
 909  */
 910 struct iscsi_cls_conn *
 911 iscsi_create_conn(struct iscsi_cls_session *session, int dd_size, uint32_t cid)
 912 {
 913         struct iscsi_transport *transport = session->transport;
 914         struct iscsi_cls_conn *conn;
 915         unsigned long flags;
 916         int err;
 917
 918         conn = kzalloc(sizeof(*conn) + dd_size, GFP_KERNEL);
 919         if (!conn)
 920                 return NULL;
 921         if (dd_size)
 922                 conn->dd_data = &conn[1];
 923
 924         INIT_LIST_HEAD(&conn->conn_list);
 925         conn->transport = transport;
 926         conn->cid = cid;
 927
 928         /* this is released in the dev's release function */
 929         if (!get_device(&session->dev))
 930                 goto free_conn;
 931
 932         dev_set_name(&conn->dev, "connection%d:%u", session->sid, cid);
 933         conn->dev.parent = &session->dev;
 934         conn->dev.release = iscsi_conn_release;
 935         err = device_register(&conn->dev);
 936         if (err) {
 937                 iscsi_cls_session_printk(KERN_ERR, session, "could not "
 938                                          "register connection's dev\n");
 939                 goto release_parent_ref;
 940         }
 941         transport_register_device(&conn->dev);
 942
 943         spin_lock_irqsave(&connlock, flags);
 944         list_add(&conn->conn_list, &connlist);
 945         conn->active = 1;
 946         spin_unlock_irqrestore(&connlock, flags);
 947
 948         ISCSI_DBG_TRANS_CONN(conn, "Completed conn creation\n");
 949         return conn;
 950
 951 release_parent_ref:
 952         put_device(&session->dev);
 953 free_conn:
 954         kfree(conn);
 955         return NULL;
 956 }
 957
 958 EXPORT_SYMBOL_GPL(iscsi_create_conn);
 959
 960 /**
 961  * iscsi_destroy_conn - destroy iscsi class connection
 962  * @conn: iscsi cls session
 963  *
 964  * This can be called from a LLD or iscsi_transport.
 965  */
 966 int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
 967 {
 968         unsigned long flags;
 969
 970         spin_lock_irqsave(&connlock, flags);
 971         conn->active = 0;
 972         list_del(&conn->conn_list);
 973         spin_unlock_irqrestore(&connlock, flags);
 974
 975         transport_unregister_device(&conn->dev);
 976         ISCSI_DBG_TRANS_CONN(conn, "Completing conn destruction\n");
 977         device_unregister(&conn->dev);
 978         return 0;
 979 }
 980 EXPORT_SYMBOL_GPL(iscsi_destroy_conn);
 981
 982 /*
 983  * iscsi interface functions
 984  */
 985 static struct iscsi_internal *
 986 iscsi_if_transport_lookup(struct iscsi_transport *tt)
 987 {
 988         struct iscsi_internal *priv;
 989         unsigned long flags;
 990
 991         spin_lock_irqsave(&iscsi_transport_lock, flags);
 992         list_for_each_entry(priv, &iscsi_transports, list) {
 993                 if (tt == priv->iscsi_transport) {
 994                         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 995                         return priv;
 996                 }
 997         }
 998         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 999         return NULL;
1000 }
1001
1002 static int
1003 iscsi_multicast_skb(struct sk_buff *skb, uint32_t group, gfp_t gfp)
1004 {
1005         return nlmsg_multicast(nls, skb, 0, group, gfp);
1006 }
1007
1008 int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
1009                    char *data, uint32_t data_size)
1010 {
1011         struct nlmsghdr *nlh;
1012         struct sk_buff *skb;
1013         struct iscsi_uevent *ev;
1014         char *pdu;
1015         struct iscsi_internal *priv;
1016         int len = NLMSG_SPACE(sizeof(*ev) + sizeof(struct iscsi_hdr) +
1017                               data_size);
1018
1019         priv = iscsi_if_transport_lookup(conn->transport);
1020         if (!priv)
1021                 return -EINVAL;
1022
1023         skb = alloc_skb(len, GFP_ATOMIC);
1024         if (!skb) {
1025                 iscsi_conn_error_event(conn, ISCSI_ERR_CONN_FAILED);
1026                 iscsi_cls_conn_printk(KERN_ERR, conn, "can not deliver "
1027                                       "control PDU: OOM\n");
1028                 return -ENOMEM;
1029         }
1030
1031         nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1032         ev = NLMSG_DATA(nlh);
1033         memset(ev, 0, sizeof(*ev));
1034         ev->transport_handle = iscsi_handle(conn->transport);
1035         ev->type = ISCSI_KEVENT_RECV_PDU;
1036         ev->r.recv_req.cid = conn->cid;
1037         ev->r.recv_req.sid = iscsi_conn_get_sid(conn);
1038         pdu = (char*)ev + sizeof(*ev);
1039         memcpy(pdu, hdr, sizeof(struct iscsi_hdr));
1040         memcpy(pdu + sizeof(struct iscsi_hdr), data, data_size);
1041
1042         return iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_ATOMIC);
1043 }
1044 EXPORT_SYMBOL_GPL(iscsi_recv_pdu);
1045
1046 int iscsi_offload_mesg(struct Scsi_Host *shost,
1047                        struct iscsi_transport *transport, uint32_t type,
1048                        char *data, uint16_t data_size)
1049 {
1050         struct nlmsghdr *nlh;
1051         struct sk_buff *skb;
1052         struct iscsi_uevent *ev;
1053         int len = NLMSG_SPACE(sizeof(*ev) + data_size);
1054
1055         skb = alloc_skb(len, GFP_ATOMIC);
1056         if (!skb) {
1057                 printk(KERN_ERR "can not deliver iscsi offload message:OOM\n");
1058                 return -ENOMEM;
1059         }
1060
1061         nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1062         ev = NLMSG_DATA(nlh);
1063         memset(ev, 0, sizeof(*ev));
1064         ev->type = type;
1065         ev->transport_handle = iscsi_handle(transport);
1066         switch (type) {
1067         case ISCSI_KEVENT_PATH_REQ:
1068                 ev->r.req_path.host_no = shost->host_no;
1069                 break;
1070         case ISCSI_KEVENT_IF_DOWN:
1071                 ev->r.notify_if_down.host_no = shost->host_no;
1072                 break;
1073         }
1074
1075         memcpy((char *)ev + sizeof(*ev), data, data_size);
1076
1077         return iscsi_multicast_skb(skb, ISCSI_NL_GRP_UIP, GFP_ATOMIC);
1078 }
1079 EXPORT_SYMBOL_GPL(iscsi_offload_mesg);
1080
1081 void iscsi_conn_error_event(struct iscsi_cls_conn *conn, enum iscsi_err error)
1082 {
1083         struct nlmsghdr *nlh;
1084         struct sk_buff  *skb;
1085         struct iscsi_uevent *ev;
1086         struct iscsi_internal *priv;
1087         int len = NLMSG_SPACE(sizeof(*ev));
1088
1089         priv = iscsi_if_transport_lookup(conn->transport);
1090         if (!priv)
1091                 return;
1092
1093         skb = alloc_skb(len, GFP_ATOMIC);
1094         if (!skb) {
1095                 iscsi_cls_conn_printk(KERN_ERR, conn, "gracefully ignored "
1096                                       "conn error (%d)\n", error);
1097                 return;
1098         }
1099
1100         nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1101         ev = NLMSG_DATA(nlh);
1102         ev->transport_handle = iscsi_handle(conn->transport);
1103         ev->type = ISCSI_KEVENT_CONN_ERROR;
1104         ev->r.connerror.error = error;
1105         ev->r.connerror.cid = conn->cid;
1106         ev->r.connerror.sid = iscsi_conn_get_sid(conn);
1107
1108         iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_ATOMIC);
1109
1110         iscsi_cls_conn_printk(KERN_INFO, conn, "detected conn error (%d)\n",
1111                               error);
1112 }
1113 EXPORT_SYMBOL_GPL(iscsi_conn_error_event);
1114
1115 static int
1116 iscsi_if_send_reply(uint32_t group, int seq, int type, int done, int multi,
1117                     void *payload, int size)
1118 {
1119         struct sk_buff  *skb;
1120         struct nlmsghdr *nlh;
1121         int len = NLMSG_SPACE(size);
1122         int flags = multi ? NLM_F_MULTI : 0;
1123         int t = done ? NLMSG_DONE : type;
1124
1125         skb = alloc_skb(len, GFP_ATOMIC);
1126         if (!skb) {
1127                 printk(KERN_ERR "Could not allocate skb to send reply.\n");
1128                 return -ENOMEM;
1129         }
1130
1131         nlh = __nlmsg_put(skb, 0, 0, t, (len - sizeof(*nlh)), 0);
1132         nlh->nlmsg_flags = flags;
1133         memcpy(NLMSG_DATA(nlh), payload, size);
1134         return iscsi_multicast_skb(skb, group, GFP_ATOMIC);
1135 }
1136
1137 static int
1138 iscsi_if_get_stats(struct iscsi_transport *transport, struct nlmsghdr *nlh)
1139 {
1140         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1141         struct iscsi_stats *stats;
1142         struct sk_buff *skbstat;
1143         struct iscsi_cls_conn *conn;
1144         struct nlmsghdr *nlhstat;
1145         struct iscsi_uevent *evstat;
1146         struct iscsi_internal *priv;
1147         int len = NLMSG_SPACE(sizeof(*ev) +
1148                               sizeof(struct iscsi_stats) +
1149                               sizeof(struct iscsi_stats_custom) *
1150                               ISCSI_STATS_CUSTOM_MAX);
1151         int err = 0;
1152
1153         priv = iscsi_if_transport_lookup(transport);
1154         if (!priv)
1155                 return -EINVAL;
1156
1157         conn = iscsi_conn_lookup(ev->u.get_stats.sid, ev->u.get_stats.cid);
1158         if (!conn)
1159                 return -EEXIST;
1160
1161         do {
1162                 int actual_size;
1163
1164                 skbstat = alloc_skb(len, GFP_ATOMIC);
1165                 if (!skbstat) {
1166                         iscsi_cls_conn_printk(KERN_ERR, conn, "can not "
1167                                               "deliver stats: OOM\n");
1168                         return -ENOMEM;
1169                 }
1170
1171                 nlhstat = __nlmsg_put(skbstat, 0, 0, 0,
1172                                       (len - sizeof(*nlhstat)), 0);
1173                 evstat = NLMSG_DATA(nlhstat);
1174                 memset(evstat, 0, sizeof(*evstat));
1175                 evstat->transport_handle = iscsi_handle(conn->transport);
1176                 evstat->type = nlh->nlmsg_type;
1177                 evstat->u.get_stats.cid =
1178                         ev->u.get_stats.cid;
1179                 evstat->u.get_stats.sid =
1180                         ev->u.get_stats.sid;
1181                 stats = (struct iscsi_stats *)
1182                         ((char*)evstat + sizeof(*evstat));
1183                 memset(stats, 0, sizeof(*stats));
1184
1185                 transport->get_stats(conn, stats);
1186                 actual_size = NLMSG_SPACE(sizeof(struct iscsi_uevent) +
1187                                           sizeof(struct iscsi_stats) +
1188                                           sizeof(struct iscsi_stats_custom) *
1189                                           stats->custom_length);
1190                 actual_size -= sizeof(*nlhstat);
1191                 actual_size = NLMSG_LENGTH(actual_size);
1192                 skb_trim(skbstat, NLMSG_ALIGN(actual_size));
1193                 nlhstat->nlmsg_len = actual_size;
1194
1195                 err = iscsi_multicast_skb(skbstat, ISCSI_NL_GRP_ISCSID,
1196                                           GFP_ATOMIC);
1197         } while (err < 0 && err != -ECONNREFUSED);
1198
1199         return err;
1200 }
1201
1202 /**
1203  * iscsi_session_event - send session destr. completion event
1204  * @session: iscsi class session
1205  * @event: type of event
1206  */
1207 int iscsi_session_event(struct iscsi_cls_session *session,
1208                         enum iscsi_uevent_e event)
1209 {
1210         struct iscsi_internal *priv;
1211         struct Scsi_Host *shost;
1212         struct iscsi_uevent *ev;
1213         struct sk_buff  *skb;
1214         struct nlmsghdr *nlh;
1215         int rc, len = NLMSG_SPACE(sizeof(*ev));
1216
1217         priv = iscsi_if_transport_lookup(session->transport);
1218         if (!priv)
1219                 return -EINVAL;
1220         shost = iscsi_session_to_shost(session);
1221
1222         skb = alloc_skb(len, GFP_KERNEL);
1223         if (!skb) {
1224                 iscsi_cls_session_printk(KERN_ERR, session,
1225                                          "Cannot notify userspace of session "
1226                                          "event %u\n", event);
1227                 return -ENOMEM;
1228         }
1229
1230         nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1231         ev = NLMSG_DATA(nlh);
1232         ev->transport_handle = iscsi_handle(session->transport);
1233
1234         ev->type = event;
1235         switch (event) {
1236         case ISCSI_KEVENT_DESTROY_SESSION:
1237                 ev->r.d_session.host_no = shost->host_no;
1238                 ev->r.d_session.sid = session->sid;
1239                 break;
1240         case ISCSI_KEVENT_CREATE_SESSION:
1241                 ev->r.c_session_ret.host_no = shost->host_no;
1242                 ev->r.c_session_ret.sid = session->sid;
1243                 break;
1244         case ISCSI_KEVENT_UNBIND_SESSION:
1245                 ev->r.unbind_session.host_no = shost->host_no;
1246                 ev->r.unbind_session.sid = session->sid;
1247                 break;
1248         default:
1249                 iscsi_cls_session_printk(KERN_ERR, session, "Invalid event "
1250                                          "%u.\n", event);
1251                 kfree_skb(skb);
1252                 return -EINVAL;
1253         }
1254
1255         /*
1256          * this will occur if the daemon is not up, so we just warn
1257          * the user and when the daemon is restarted it will handle it
1258          */
1259         rc = iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_KERNEL);
1260         if (rc == -ESRCH)
1261                 iscsi_cls_session_printk(KERN_ERR, session,
1262                                          "Cannot notify userspace of session "
1263                                          "event %u. Check iscsi daemon\n",
1264                                          event);
1265
1266         ISCSI_DBG_TRANS_SESSION(session, "Completed handling event %d rc %d\n",
1267                                 event, rc);
1268         return rc;
1269 }
1270 EXPORT_SYMBOL_GPL(iscsi_session_event);
1271
1272 static int
1273 iscsi_if_create_session(struct iscsi_internal *priv, struct iscsi_endpoint *ep,
1274                         struct iscsi_uevent *ev, uint32_t initial_cmdsn,
1275                         uint16_t cmds_max, uint16_t queue_depth)
1276 {
1277         struct iscsi_transport *transport = priv->iscsi_transport;
1278         struct iscsi_cls_session *session;
1279         struct Scsi_Host *shost;
1280
1281         session = transport->create_session(ep, cmds_max, queue_depth,
1282                                             initial_cmdsn);
1283         if (!session)
1284                 return -ENOMEM;
1285
1286         shost = iscsi_session_to_shost(session);
1287         ev->r.c_session_ret.host_no = shost->host_no;
1288         ev->r.c_session_ret.sid = session->sid;
1289         ISCSI_DBG_TRANS_SESSION(session,
1290                                 "Completed creating transport session\n");
1291         return 0;
1292 }
1293
1294 static int
1295 iscsi_if_create_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1296 {
1297         struct iscsi_cls_conn *conn;
1298         struct iscsi_cls_session *session;
1299
1300         session = iscsi_session_lookup(ev->u.c_conn.sid);
1301         if (!session) {
1302                 printk(KERN_ERR "iscsi: invalid session %d.\n",
1303                        ev->u.c_conn.sid);
1304                 return -EINVAL;
1305         }
1306
1307         conn = transport->create_conn(session, ev->u.c_conn.cid);
1308         if (!conn) {
1309                 iscsi_cls_session_printk(KERN_ERR, session,
1310                                          "couldn't create a new connection.");
1311                 return -ENOMEM;
1312         }
1313
1314         ev->r.c_conn_ret.sid = session->sid;
1315         ev->r.c_conn_ret.cid = conn->cid;
1316
1317         ISCSI_DBG_TRANS_CONN(conn, "Completed creating transport conn\n");
1318         return 0;
1319 }
1320
1321 static int
1322 iscsi_if_destroy_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1323 {
1324         struct iscsi_cls_conn *conn;
1325
1326         conn = iscsi_conn_lookup(ev->u.d_conn.sid, ev->u.d_conn.cid);
1327         if (!conn)
1328                 return -EINVAL;
1329
1330         ISCSI_DBG_TRANS_CONN(conn, "Destroying transport conn\n");
1331         if (transport->destroy_conn)
1332                 transport->destroy_conn(conn);
1333
1334         return 0;
1335 }
1336
1337 static int
1338 iscsi_set_param(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1339 {
1340         char *data = (char*)ev + sizeof(*ev);
1341         struct iscsi_cls_conn *conn;
1342         struct iscsi_cls_session *session;
1343         int err = 0, value = 0;
1344
1345         session = iscsi_session_lookup(ev->u.set_param.sid);
1346         conn = iscsi_conn_lookup(ev->u.set_param.sid, ev->u.set_param.cid);
1347         if (!conn || !session)
1348                 return -EINVAL;
1349
1350         switch (ev->u.set_param.param) {
1351         case ISCSI_PARAM_SESS_RECOVERY_TMO:
1352                 sscanf(data, "%d", &value);
1353                 session->recovery_tmo = value;
1354                 break;
1355         default:
1356                 err = transport->set_param(conn, ev->u.set_param.param,
1357                                            data, ev->u.set_param.len);
1358         }
1359
1360         return err;
1361 }
1362
1363 static int iscsi_if_ep_connect(struct iscsi_transport *transport,
1364                                struct iscsi_uevent *ev, int msg_type)
1365 {
1366         struct iscsi_endpoint *ep;
1367         struct sockaddr *dst_addr;
1368         struct Scsi_Host *shost = NULL;
1369         int non_blocking, err = 0;
1370
1371         if (!transport->ep_connect)
1372                 return -EINVAL;
1373
1374         if (msg_type == ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST) {
1375                 shost = scsi_host_lookup(ev->u.ep_connect_through_host.host_no);
1376                 if (!shost) {
1377                         printk(KERN_ERR "ep connect failed. Could not find "
1378                                "host no %u\n",
1379                                ev->u.ep_connect_through_host.host_no);
1380                         return -ENODEV;
1381                 }
1382                 non_blocking = ev->u.ep_connect_through_host.non_blocking;
1383         } else
1384                 non_blocking = ev->u.ep_connect.non_blocking;
1385
1386         dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1387         ep = transport->ep_connect(shost, dst_addr, non_blocking);
1388         if (IS_ERR(ep)) {
1389                 err = PTR_ERR(ep);
1390                 goto release_host;
1391         }
1392
1393         ev->r.ep_connect_ret.handle = ep->id;
1394 release_host:
1395         if (shost)
1396                 scsi_host_put(shost);
1397         return err;
1398 }
1399
1400 static int
1401 iscsi_if_transport_ep(struct iscsi_transport *transport,
1402                       struct iscsi_uevent *ev, int msg_type)
1403 {
1404         struct iscsi_endpoint *ep;
1405         int rc = 0;
1406
1407         switch (msg_type) {
1408         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST:
1409         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1410                 rc = iscsi_if_ep_connect(transport, ev, msg_type);
1411                 break;
1412         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1413                 if (!transport->ep_poll)
1414                         return -EINVAL;
1415
1416                 ep = iscsi_lookup_endpoint(ev->u.ep_poll.ep_handle);
1417                 if (!ep)
1418                         return -EINVAL;
1419
1420                 ev->r.retcode = transport->ep_poll(ep,
1421                                                    ev->u.ep_poll.timeout_ms);
1422                 break;
1423         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1424                 if (!transport->ep_disconnect)
1425                         return -EINVAL;
1426
1427                 ep = iscsi_lookup_endpoint(ev->u.ep_disconnect.ep_handle);
1428                 if (!ep)
1429                         return -EINVAL;
1430
1431                 transport->ep_disconnect(ep);
1432                 break;
1433         }
1434         return rc;
1435 }
1436
1437 static int
1438 iscsi_tgt_dscvr(struct iscsi_transport *transport,
1439                 struct iscsi_uevent *ev)
1440 {
1441         struct Scsi_Host *shost;
1442         struct sockaddr *dst_addr;
1443         int err;
1444
1445         if (!transport->tgt_dscvr)
1446                 return -EINVAL;
1447
1448         shost = scsi_host_lookup(ev->u.tgt_dscvr.host_no);
1449         if (!shost) {
1450                 printk(KERN_ERR "target discovery could not find host no %u\n",
1451                        ev->u.tgt_dscvr.host_no);
1452                 return -ENODEV;
1453         }
1454
1455
1456         dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1457         err = transport->tgt_dscvr(shost, ev->u.tgt_dscvr.type,
1458                                    ev->u.tgt_dscvr.enable, dst_addr);
1459         scsi_host_put(shost);
1460         return err;
1461 }
1462
1463 static int
1464 iscsi_set_host_param(struct iscsi_transport *transport,
1465                      struct iscsi_uevent *ev)
1466 {
1467         char *data = (char*)ev + sizeof(*ev);
1468         struct Scsi_Host *shost;
1469         int err;
1470
1471         if (!transport->set_host_param)
1472                 return -ENOSYS;
1473
1474         shost = scsi_host_lookup(ev->u.set_host_param.host_no);
1475         if (!shost) {
1476                 printk(KERN_ERR "set_host_param could not find host no %u\n",
1477                        ev->u.set_host_param.host_no);
1478                 return -ENODEV;
1479         }
1480
1481         err = transport->set_host_param(shost, ev->u.set_host_param.param,
1482                                         data, ev->u.set_host_param.len);
1483         scsi_host_put(shost);
1484         return err;
1485 }
1486
1487 static int
1488 iscsi_set_path(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1489 {
1490         struct Scsi_Host *shost;
1491         struct iscsi_path *params;
1492         int err;
1493
1494         if (!transport->set_path)
1495                 return -ENOSYS;
1496
1497         shost = scsi_host_lookup(ev->u.set_path.host_no);
1498         if (!shost) {
1499                 printk(KERN_ERR "set path could not find host no %u\n",
1500                        ev->u.set_path.host_no);
1501                 return -ENODEV;
1502         }
1503
1504         params = (struct iscsi_path *)((char *)ev + sizeof(*ev));
1505         err = transport->set_path(shost, params);
1506
1507         scsi_host_put(shost);
1508         return err;
1509 }
1510
1511 static int
1512 iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, uint32_t *group)
1513 {
1514         int err = 0;
1515         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1516         struct iscsi_transport *transport = NULL;
1517         struct iscsi_internal *priv;
1518         struct iscsi_cls_session *session;
1519         struct iscsi_cls_conn *conn;
1520         struct iscsi_endpoint *ep = NULL;
1521
1522         if (nlh->nlmsg_type == ISCSI_UEVENT_PATH_UPDATE)
1523                 *group = ISCSI_NL_GRP_UIP;
1524         else
1525                 *group = ISCSI_NL_GRP_ISCSID;
1526
1527         priv = iscsi_if_transport_lookup(iscsi_ptr(ev->transport_handle));
1528         if (!priv)
1529                 return -EINVAL;
1530         transport = priv->iscsi_transport;
1531
1532         if (!try_module_get(transport->owner))
1533                 return -EINVAL;
1534
1535         switch (nlh->nlmsg_type) {
1536         case ISCSI_UEVENT_CREATE_SESSION:
1537                 err = iscsi_if_create_session(priv, ep, ev,
1538                                               ev->u.c_session.initial_cmdsn,
1539                                               ev->u.c_session.cmds_max,
1540                                               ev->u.c_session.queue_depth);
1541                 break;
1542         case ISCSI_UEVENT_CREATE_BOUND_SESSION:
1543                 ep = iscsi_lookup_endpoint(ev->u.c_bound_session.ep_handle);
1544                 if (!ep) {
1545                         err = -EINVAL;
1546                         break;
1547                 }
1548
1549                 err = iscsi_if_create_session(priv, ep, ev,
1550                                         ev->u.c_bound_session.initial_cmdsn,
1551                                         ev->u.c_bound_session.cmds_max,
1552                                         ev->u.c_bound_session.queue_depth);
1553                 break;
1554         case ISCSI_UEVENT_DESTROY_SESSION:
1555                 session = iscsi_session_lookup(ev->u.d_session.sid);
1556                 if (session)
1557                         transport->destroy_session(session);
1558                 else
1559                         err = -EINVAL;
1560                 break;
1561         case ISCSI_UEVENT_UNBIND_SESSION:
1562                 session = iscsi_session_lookup(ev->u.d_session.sid);
1563                 if (session)
1564                         scsi_queue_work(iscsi_session_to_shost(session),
1565                                         &session->unbind_work);
1566                 else
1567                         err = -EINVAL;
1568                 break;
1569         case ISCSI_UEVENT_CREATE_CONN:
1570                 err = iscsi_if_create_conn(transport, ev);
1571                 break;
1572         case ISCSI_UEVENT_DESTROY_CONN:
1573                 err = iscsi_if_destroy_conn(transport, ev);
1574                 break;
1575         case ISCSI_UEVENT_BIND_CONN:
1576                 session = iscsi_session_lookup(ev->u.b_conn.sid);
1577                 conn = iscsi_conn_lookup(ev->u.b_conn.sid, ev->u.b_conn.cid);
1578
1579                 if (session && conn)
1580                         ev->r.retcode = transport->bind_conn(session, conn,
1581                                         ev->u.b_conn.transport_eph,
1582                                         ev->u.b_conn.is_leading);
1583                 else
1584                         err = -EINVAL;
1585                 break;
1586         case ISCSI_UEVENT_SET_PARAM:
1587                 err = iscsi_set_param(transport, ev);
1588                 break;
1589         case ISCSI_UEVENT_START_CONN:
1590                 conn = iscsi_conn_lookup(ev->u.start_conn.sid, ev->u.start_conn.cid);
1591                 if (conn)
1592                         ev->r.retcode = transport->start_conn(conn);
1593                 else
1594                         err = -EINVAL;
1595                 break;
1596         case ISCSI_UEVENT_STOP_CONN:
1597                 conn = iscsi_conn_lookup(ev->u.stop_conn.sid, ev->u.stop_conn.cid);
1598                 if (conn)
1599                         transport->stop_conn(conn, ev->u.stop_conn.flag);
1600                 else
1601                         err = -EINVAL;
1602                 break;
1603         case ISCSI_UEVENT_SEND_PDU:
1604                 conn = iscsi_conn_lookup(ev->u.send_pdu.sid, ev->u.send_pdu.cid);
1605                 if (conn)
1606                         ev->r.retcode = transport->send_pdu(conn,
1607                                 (struct iscsi_hdr*)((char*)ev + sizeof(*ev)),
1608                                 (char*)ev + sizeof(*ev) + ev->u.send_pdu.hdr_size,
1609                                 ev->u.send_pdu.data_size);
1610                 else
1611                         err = -EINVAL;
1612                 break;
1613         case ISCSI_UEVENT_GET_STATS:
1614                 err = iscsi_if_get_stats(transport, nlh);
1615                 break;
1616         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1617         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1618         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1619         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST:
1620                 err = iscsi_if_transport_ep(transport, ev, nlh->nlmsg_type);
1621                 break;
1622         case ISCSI_UEVENT_TGT_DSCVR:
1623                 err = iscsi_tgt_dscvr(transport, ev);
1624                 break;
1625         case ISCSI_UEVENT_SET_HOST_PARAM:
1626                 err = iscsi_set_host_param(transport, ev);
1627                 break;
1628         case ISCSI_UEVENT_PATH_UPDATE:
1629                 err = iscsi_set_path(transport, ev);
1630                 break;
1631         default:
1632                 err = -ENOSYS;
1633                 break;
1634         }
1635
1636         module_put(transport->owner);
1637         return err;
1638 }
1639
1640 /*
1641  * Get message from skb.  Each message is processed by iscsi_if_recv_msg.
1642  * Malformed skbs with wrong lengths or invalid creds are not processed.
1643  */
1644 static void
1645 iscsi_if_rx(struct sk_buff *skb)
1646 {
1647         mutex_lock(&rx_queue_mutex);
1648         while (skb->len >= NLMSG_SPACE(0)) {
1649                 int err;
1650                 uint32_t rlen;
1651                 struct nlmsghdr *nlh;
1652                 struct iscsi_uevent *ev;
1653                 uint32_t group;
1654
1655                 nlh = nlmsg_hdr(skb);
1656                 if (nlh->nlmsg_len < sizeof(*nlh) ||
1657                     skb->len < nlh->nlmsg_len) {
1658                         break;
1659                 }
1660
1661                 ev = NLMSG_DATA(nlh);
1662                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1663                 if (rlen > skb->len)
1664                         rlen = skb->len;
1665
1666                 err = iscsi_if_recv_msg(skb, nlh, &group);
1667                 if (err) {
1668                         ev->type = ISCSI_KEVENT_IF_ERROR;
1669                         ev->iferror = err;
1670                 }
1671                 do {
1672                         /*
1673                          * special case for GET_STATS:
1674                          * on success - sending reply and stats from
1675                          * inside of if_recv_msg(),
1676                          * on error - fall through.
1677                          */
1678                         if (ev->type == ISCSI_UEVENT_GET_STATS && !err)
1679                                 break;
1680                         err = iscsi_if_send_reply(group, nlh->nlmsg_seq,
1681                                 nlh->nlmsg_type, 0, 0, ev, sizeof(*ev));
1682                 } while (err < 0 && err != -ECONNREFUSED);
1683                 skb_pull(skb, rlen);
1684         }
1685         mutex_unlock(&rx_queue_mutex);
1686 }
1687
1688 #define ISCSI_CLASS_ATTR(_prefix,_name,_mode,_show,_store)              \
1689 struct device_attribute dev_attr_##_prefix##_##_name =  \
1690         __ATTR(_name,_mode,_show,_store)
1691
1692 /*
1693  * iSCSI connection attrs
1694  */
1695 #define iscsi_conn_attr_show(param)                                     \
1696 static ssize_t                                                          \
1697 show_conn_param_##param(struct device *dev,                             \
1698                         struct device_attribute *attr, char *buf)       \
1699 {                                                                       \
1700         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev->parent);   \
1701         struct iscsi_transport *t = conn->transport;                    \
1702         return t->get_conn_param(conn, param, buf);                     \
1703 }
1704
1705 #define iscsi_conn_attr(field, param)                                   \
1706         iscsi_conn_attr_show(param)                                     \
1707 static ISCSI_CLASS_ATTR(conn, field, S_IRUGO, show_conn_param_##param,  \
1708                         NULL);
1709
1710 iscsi_conn_attr(max_recv_dlength, ISCSI_PARAM_MAX_RECV_DLENGTH);
1711 iscsi_conn_attr(max_xmit_dlength, ISCSI_PARAM_MAX_XMIT_DLENGTH);
1712 iscsi_conn_attr(header_digest, ISCSI_PARAM_HDRDGST_EN);
1713 iscsi_conn_attr(data_digest, ISCSI_PARAM_DATADGST_EN);
1714 iscsi_conn_attr(ifmarker, ISCSI_PARAM_IFMARKER_EN);
1715 iscsi_conn_attr(ofmarker, ISCSI_PARAM_OFMARKER_EN);
1716 iscsi_conn_attr(persistent_port, ISCSI_PARAM_PERSISTENT_PORT);
1717 iscsi_conn_attr(port, ISCSI_PARAM_CONN_PORT);
1718 iscsi_conn_attr(exp_statsn, ISCSI_PARAM_EXP_STATSN);
1719 iscsi_conn_attr(persistent_address, ISCSI_PARAM_PERSISTENT_ADDRESS);
1720 iscsi_conn_attr(address, ISCSI_PARAM_CONN_ADDRESS);
1721 iscsi_conn_attr(ping_tmo, ISCSI_PARAM_PING_TMO);
1722 iscsi_conn_attr(recv_tmo, ISCSI_PARAM_RECV_TMO);
1723
1724 /*
1725  * iSCSI session attrs
1726  */
1727 #define iscsi_session_attr_show(param, perm)                            \
1728 static ssize_t                                                          \
1729 show_session_param_##param(struct device *dev,                          \
1730                            struct device_attribute *attr, char *buf)    \
1731 {                                                                       \
1732         struct iscsi_cls_session *session =                             \
1733                 iscsi_dev_to_session(dev->parent);                      \
1734         struct iscsi_transport *t = session->transport;                 \
1735                                                                         \
1736         if (perm && !capable(CAP_SYS_ADMIN))                            \
1737                 return -EACCES;                                         \
1738         return t->get_session_param(session, param, buf);               \
1739 }
1740
1741 #define iscsi_session_attr(field, param, perm)                          \
1742         iscsi_session_attr_show(param, perm)                            \
1743 static ISCSI_CLASS_ATTR(sess, field, S_IRUGO, show_session_param_##param, \
1744                         NULL);
1745
1746 iscsi_session_attr(targetname, ISCSI_PARAM_TARGET_NAME, 0);
1747 iscsi_session_attr(initial_r2t, ISCSI_PARAM_INITIAL_R2T_EN, 0);
1748 iscsi_session_attr(max_outstanding_r2t, ISCSI_PARAM_MAX_R2T, 0);
1749 iscsi_session_attr(immediate_data, ISCSI_PARAM_IMM_DATA_EN, 0);
1750 iscsi_session_attr(first_burst_len, ISCSI_PARAM_FIRST_BURST, 0);
1751 iscsi_session_attr(max_burst_len, ISCSI_PARAM_MAX_BURST, 0);
1752 iscsi_session_attr(data_pdu_in_order, ISCSI_PARAM_PDU_INORDER_EN, 0);
1753 iscsi_session_attr(data_seq_in_order, ISCSI_PARAM_DATASEQ_INORDER_EN, 0);
1754 iscsi_session_attr(erl, ISCSI_PARAM_ERL, 0);
1755 iscsi_session_attr(tpgt, ISCSI_PARAM_TPGT, 0);
1756 iscsi_session_attr(username, ISCSI_PARAM_USERNAME, 1);
1757 iscsi_session_attr(username_in, ISCSI_PARAM_USERNAME_IN, 1);
1758 iscsi_session_attr(password, ISCSI_PARAM_PASSWORD, 1);
1759 iscsi_session_attr(password_in, ISCSI_PARAM_PASSWORD_IN, 1);
1760 iscsi_session_attr(fast_abort, ISCSI_PARAM_FAST_ABORT, 0);
1761 iscsi_session_attr(abort_tmo, ISCSI_PARAM_ABORT_TMO, 0);
1762 iscsi_session_attr(lu_reset_tmo, ISCSI_PARAM_LU_RESET_TMO, 0);
1763 iscsi_session_attr(tgt_reset_tmo, ISCSI_PARAM_TGT_RESET_TMO, 0);
1764 iscsi_session_attr(ifacename, ISCSI_PARAM_IFACE_NAME, 0);
1765 iscsi_session_attr(initiatorname, ISCSI_PARAM_INITIATOR_NAME, 0)
1766
1767 static ssize_t
1768 show_priv_session_state(struct device *dev, struct device_attribute *attr,
1769                         char *buf)
1770 {
1771         struct iscsi_cls_session *session = iscsi_dev_to_session(dev->parent);
1772         return sprintf(buf, "%s\n", iscsi_session_state_name(session->state));
1773 }
1774 static ISCSI_CLASS_ATTR(priv_sess, state, S_IRUGO, show_priv_session_state,
1775                         NULL);
1776
1777 #define iscsi_priv_session_attr_show(field, format)                     \
1778 static ssize_t                                                          \
1779 show_priv_session_##field(struct device *dev,                           \
1780                           struct device_attribute *attr, char *buf)     \
1781 {                                                                       \
1782         struct iscsi_cls_session *session =                             \
1783                         iscsi_dev_to_session(dev->parent);              \
1784         return sprintf(buf, format"\n", session->field);                \
1785 }
1786
1787 #define iscsi_priv_session_attr(field, format)                          \
1788         iscsi_priv_session_attr_show(field, format)                     \
1789 static ISCSI_CLASS_ATTR(priv_sess, field, S_IRUGO, show_priv_session_##field, \
1790                         NULL)
1791 iscsi_priv_session_attr(recovery_tmo, "%d");
1792
1793 /*
1794  * iSCSI host attrs
1795  */
1796 #define iscsi_host_attr_show(param)                                     \
1797 static ssize_t                                                          \
1798 show_host_param_##param(struct device *dev,                             \
1799                         struct device_attribute *attr, char *buf)       \
1800 {                                                                       \
1801         struct Scsi_Host *shost = transport_class_to_shost(dev);        \
1802         struct iscsi_internal *priv = to_iscsi_internal(shost->transportt); \
1803         return priv->iscsi_transport->get_host_param(shost, param, buf); \
1804 }
1805
1806 #define iscsi_host_attr(field, param)                                   \
1807         iscsi_host_attr_show(param)                                     \
1808 static ISCSI_CLASS_ATTR(host, field, S_IRUGO, show_host_param_##param,  \
1809                         NULL);
1810
1811 iscsi_host_attr(netdev, ISCSI_HOST_PARAM_NETDEV_NAME);
1812 iscsi_host_attr(hwaddress, ISCSI_HOST_PARAM_HWADDRESS);
1813 iscsi_host_attr(ipaddress, ISCSI_HOST_PARAM_IPADDRESS);
1814 iscsi_host_attr(initiatorname, ISCSI_HOST_PARAM_INITIATOR_NAME);
1815
1816 #define SETUP_PRIV_SESSION_RD_ATTR(field)                               \
1817 do {                                                                    \
1818         priv->session_attrs[count] = &dev_attr_priv_sess_##field; \
1819         count++;                                                        \
1820 } while (0)
1821
1822
1823 #define SETUP_SESSION_RD_ATTR(field, param_flag)                        \
1824 do {                                                                    \
1825         if (tt->param_mask & param_flag) {                              \
1826                 priv->session_attrs[count] = &dev_attr_sess_##field; \
1827                 count++;                                                \
1828         }                                                               \
1829 } while (0)
1830
1831 #define SETUP_CONN_RD_ATTR(field, param_flag)                           \
1832 do {                                                                    \
1833         if (tt->param_mask & param_flag) {                              \
1834                 priv->conn_attrs[count] = &dev_attr_conn_##field; \
1835                 count++;                                                \
1836         }                                                               \
1837 } while (0)
1838
1839 #define SETUP_HOST_RD_ATTR(field, param_flag)                           \
1840 do {                                                                    \
1841         if (tt->host_param_mask & param_flag) {                         \
1842                 priv->host_attrs[count] = &dev_attr_host_##field; \
1843                 count++;                                                \
1844         }                                                               \
1845 } while (0)
1846
1847 static int iscsi_session_match(struct attribute_container *cont,
1848                            struct device *dev)
1849 {
1850         struct iscsi_cls_session *session;
1851         struct Scsi_Host *shost;
1852         struct iscsi_internal *priv;
1853
1854         if (!iscsi_is_session_dev(dev))
1855                 return 0;
1856
1857         session = iscsi_dev_to_session(dev);
1858         shost = iscsi_session_to_shost(session);
1859         if (!shost->transportt)
1860                 return 0;
1861
1862         priv = to_iscsi_internal(shost->transportt);
1863         if (priv->session_cont.ac.class != &iscsi_session_class.class)
1864                 return 0;
1865
1866         return &priv->session_cont.ac == cont;
1867 }
1868
1869 static int iscsi_conn_match(struct attribute_container *cont,
1870                            struct device *dev)
1871 {
1872         struct iscsi_cls_session *session;
1873         struct iscsi_cls_conn *conn;
1874         struct Scsi_Host *shost;
1875         struct iscsi_internal *priv;
1876
1877         if (!iscsi_is_conn_dev(dev))
1878                 return 0;
1879
1880         conn = iscsi_dev_to_conn(dev);
1881         session = iscsi_dev_to_session(conn->dev.parent);
1882         shost = iscsi_session_to_shost(session);
1883
1884         if (!shost->transportt)
1885                 return 0;
1886
1887         priv = to_iscsi_internal(shost->transportt);
1888         if (priv->conn_cont.ac.class != &iscsi_connection_class.class)
1889                 return 0;
1890
1891         return &priv->conn_cont.ac == cont;
1892 }
1893
1894 static int iscsi_host_match(struct attribute_container *cont,
1895                             struct device *dev)
1896 {
1897         struct Scsi_Host *shost;
1898         struct iscsi_internal *priv;
1899
1900         if (!scsi_is_host_device(dev))
1901                 return 0;
1902
1903         shost = dev_to_shost(dev);
1904         if (!shost->transportt  ||
1905             shost->transportt->host_attrs.ac.class != &iscsi_host_class.class)
1906                 return 0;
1907
1908         priv = to_iscsi_internal(shost->transportt);
1909         return &priv->t.host_attrs.ac == cont;
1910 }
1911
1912 struct scsi_transport_template *
1913 iscsi_register_transport(struct iscsi_transport *tt)
1914 {
1915         struct iscsi_internal *priv;
1916         unsigned long flags;
1917         int count = 0, err;
1918
1919         BUG_ON(!tt);
1920
1921         priv = iscsi_if_transport_lookup(tt);
1922         if (priv)
1923                 return NULL;
1924
1925         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1926         if (!priv)
1927                 return NULL;
1928         INIT_LIST_HEAD(&priv->list);
1929         priv->iscsi_transport = tt;
1930         priv->t.user_scan = iscsi_user_scan;
1931         priv->t.create_work_queue = 1;
1932
1933         priv->dev.class = &iscsi_transport_class;
1934         dev_set_name(&priv->dev, "%s", tt->name);
1935         err = device_register(&priv->dev);
1936         if (err)
1937                 goto free_priv;
1938
1939         err = sysfs_create_group(&priv->dev.kobj, &iscsi_transport_group);
1940         if (err)
1941                 goto unregister_dev;
1942
1943         /* host parameters */
1944         priv->t.host_attrs.ac.attrs = &priv->host_attrs[0];
1945         priv->t.host_attrs.ac.class = &iscsi_host_class.class;
1946         priv->t.host_attrs.ac.match = iscsi_host_match;
1947         priv->t.host_size = sizeof(struct iscsi_cls_host);
1948         transport_container_register(&priv->t.host_attrs);
1949
1950         SETUP_HOST_RD_ATTR(netdev, ISCSI_HOST_NETDEV_NAME);
1951         SETUP_HOST_RD_ATTR(ipaddress, ISCSI_HOST_IPADDRESS);
1952         SETUP_HOST_RD_ATTR(hwaddress, ISCSI_HOST_HWADDRESS);
1953         SETUP_HOST_RD_ATTR(initiatorname, ISCSI_HOST_INITIATOR_NAME);
1954         BUG_ON(count > ISCSI_HOST_ATTRS);
1955         priv->host_attrs[count] = NULL;
1956         count = 0;
1957
1958         /* connection parameters */
1959         priv->conn_cont.ac.attrs = &priv->conn_attrs[0];
1960         priv->conn_cont.ac.class = &iscsi_connection_class.class;
1961         priv->conn_cont.ac.match = iscsi_conn_match;
1962         transport_container_register(&priv->conn_cont);
1963
1964         SETUP_CONN_RD_ATTR(max_recv_dlength, ISCSI_MAX_RECV_DLENGTH);
1965         SETUP_CONN_RD_ATTR(max_xmit_dlength, ISCSI_MAX_XMIT_DLENGTH);
1966         SETUP_CONN_RD_ATTR(header_digest, ISCSI_HDRDGST_EN);
1967         SETUP_CONN_RD_ATTR(data_digest, ISCSI_DATADGST_EN);
1968         SETUP_CONN_RD_ATTR(ifmarker, ISCSI_IFMARKER_EN);
1969         SETUP_CONN_RD_ATTR(ofmarker, ISCSI_OFMARKER_EN);
1970         SETUP_CONN_RD_ATTR(address, ISCSI_CONN_ADDRESS);
1971         SETUP_CONN_RD_ATTR(port, ISCSI_CONN_PORT);
1972         SETUP_CONN_RD_ATTR(exp_statsn, ISCSI_EXP_STATSN);
1973         SETUP_CONN_RD_ATTR(persistent_address, ISCSI_PERSISTENT_ADDRESS);
1974         SETUP_CONN_RD_ATTR(persistent_port, ISCSI_PERSISTENT_PORT);
1975         SETUP_CONN_RD_ATTR(ping_tmo, ISCSI_PING_TMO);
1976         SETUP_CONN_RD_ATTR(recv_tmo, ISCSI_RECV_TMO);
1977
1978         BUG_ON(count > ISCSI_CONN_ATTRS);
1979         priv->conn_attrs[count] = NULL;
1980         count = 0;
1981
1982         /* session parameters */
1983         priv->session_cont.ac.attrs = &priv->session_attrs[0];
1984         priv->session_cont.ac.class = &iscsi_session_class.class;
1985         priv->session_cont.ac.match = iscsi_session_match;
1986         transport_container_register(&priv->session_cont);
1987
1988         SETUP_SESSION_RD_ATTR(initial_r2t, ISCSI_INITIAL_R2T_EN);
1989         SETUP_SESSION_RD_ATTR(max_outstanding_r2t, ISCSI_MAX_R2T);
1990         SETUP_SESSION_RD_ATTR(immediate_data, ISCSI_IMM_DATA_EN);
1991         SETUP_SESSION_RD_ATTR(first_burst_len, ISCSI_FIRST_BURST);
1992         SETUP_SESSION_RD_ATTR(max_burst_len, ISCSI_MAX_BURST);
1993         SETUP_SESSION_RD_ATTR(data_pdu_in_order, ISCSI_PDU_INORDER_EN);
1994         SETUP_SESSION_RD_ATTR(data_seq_in_order, ISCSI_DATASEQ_INORDER_EN);
1995         SETUP_SESSION_RD_ATTR(erl, ISCSI_ERL);
1996         SETUP_SESSION_RD_ATTR(targetname, ISCSI_TARGET_NAME);
1997         SETUP_SESSION_RD_ATTR(tpgt, ISCSI_TPGT);
1998         SETUP_SESSION_RD_ATTR(password, ISCSI_USERNAME);
1999         SETUP_SESSION_RD_ATTR(password_in, ISCSI_USERNAME_IN);
2000         SETUP_SESSION_RD_ATTR(username, ISCSI_PASSWORD);
2001         SETUP_SESSION_RD_ATTR(username_in, ISCSI_PASSWORD_IN);
2002         SETUP_SESSION_RD_ATTR(fast_abort, ISCSI_FAST_ABORT);
2003         SETUP_SESSION_RD_ATTR(abort_tmo, ISCSI_ABORT_TMO);
2004         SETUP_SESSION_RD_ATTR(lu_reset_tmo,ISCSI_LU_RESET_TMO);
2005         SETUP_SESSION_RD_ATTR(tgt_reset_tmo,ISCSI_TGT_RESET_TMO);
2006         SETUP_SESSION_RD_ATTR(ifacename, ISCSI_IFACE_NAME);
2007         SETUP_SESSION_RD_ATTR(initiatorname, ISCSI_INITIATOR_NAME);
2008         SETUP_PRIV_SESSION_RD_ATTR(recovery_tmo);
2009         SETUP_PRIV_SESSION_RD_ATTR(state);
2010
2011         BUG_ON(count > ISCSI_SESSION_ATTRS);
2012         priv->session_attrs[count] = NULL;
2013
2014         spin_lock_irqsave(&iscsi_transport_lock, flags);
2015         list_add(&priv->list, &iscsi_transports);
2016         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
2017
2018         printk(KERN_NOTICE "iscsi: registered transport (%s)\n", tt->name);
2019         return &priv->t;
2020
2021 unregister_dev:
2022         device_unregister(&priv->dev);
2023         return NULL;
2024 free_priv:
2025         kfree(priv);
2026         return NULL;
2027 }
2028 EXPORT_SYMBOL_GPL(iscsi_register_transport);
2029
2030 int iscsi_unregister_transport(struct iscsi_transport *tt)
2031 {
2032         struct iscsi_internal *priv;
2033         unsigned long flags;
2034
2035         BUG_ON(!tt);
2036
2037         mutex_lock(&rx_queue_mutex);
2038
2039         priv = iscsi_if_transport_lookup(tt);
2040         BUG_ON (!priv);
2041
2042         spin_lock_irqsave(&iscsi_transport_lock, flags);
2043         list_del(&priv->list);
2044         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
2045
2046         transport_container_unregister(&priv->conn_cont);
2047         transport_container_unregister(&priv->session_cont);
2048         transport_container_unregister(&priv->t.host_attrs);
2049
2050         sysfs_remove_group(&priv->dev.kobj, &iscsi_transport_group);
2051         device_unregister(&priv->dev);
2052         mutex_unlock(&rx_queue_mutex);
2053
2054         return 0;
2055 }
2056 EXPORT_SYMBOL_GPL(iscsi_unregister_transport);
2057
2058 static __init int iscsi_transport_init(void)
2059 {
2060         int err;
2061
2062         printk(KERN_INFO "Loading iSCSI transport class v%s.\n",
2063                 ISCSI_TRANSPORT_VERSION);
2064
2065         atomic_set(&iscsi_session_nr, 0);
2066
2067         err = class_register(&iscsi_transport_class);
2068         if (err)
2069                 return err;
2070
2071         err = class_register(&iscsi_endpoint_class);
2072         if (err)
2073                 goto unregister_transport_class;
2074
2075         err = transport_class_register(&iscsi_host_class);
2076         if (err)
2077                 goto unregister_endpoint_class;
2078
2079         err = transport_class_register(&iscsi_connection_class);
2080         if (err)
2081                 goto unregister_host_class;
2082
2083         err = transport_class_register(&iscsi_session_class);
2084         if (err)
2085                 goto unregister_conn_class;
2086
2087         nls = netlink_kernel_create(&init_net, NETLINK_ISCSI, 1, iscsi_if_rx,
2088                                     NULL, THIS_MODULE);
2089         if (!nls) {
2090                 err = -ENOBUFS;
2091                 goto unregister_session_class;
2092         }
2093
2094         iscsi_eh_timer_workq = create_singlethread_workqueue("iscsi_eh");
2095         if (!iscsi_eh_timer_workq)
2096                 goto release_nls;
2097
2098         return 0;
2099
2100 release_nls:
2101         netlink_kernel_release(nls);
2102 unregister_session_class:
2103         transport_class_unregister(&iscsi_session_class);
2104 unregister_conn_class:
2105         transport_class_unregister(&iscsi_connection_class);
2106 unregister_host_class:
2107         transport_class_unregister(&iscsi_host_class);
2108 unregister_endpoint_class:
2109         class_unregister(&iscsi_endpoint_class);
2110 unregister_transport_class:
2111         class_unregister(&iscsi_transport_class);
2112         return err;
2113 }
2114
2115 static void __exit iscsi_transport_exit(void)
2116 {
2117         destroy_workqueue(iscsi_eh_timer_workq);
2118         netlink_kernel_release(nls);
2119         transport_class_unregister(&iscsi_connection_class);
2120         transport_class_unregister(&iscsi_session_class);
2121         transport_class_unregister(&iscsi_host_class);
2122         class_unregister(&iscsi_endpoint_class);
2123         class_unregister(&iscsi_transport_class);
2124 }
2125
2126 module_init(iscsi_transport_init);
2127 module_exit(iscsi_transport_exit);
2128
2129 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
2130               "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
2131               "Alex Aizman <itn780@yahoo.com>");
2132 MODULE_DESCRIPTION("iSCSI Transport Interface");
2133 MODULE_LICENSE("GPL");
2134 MODULE_VERSION(ISCSI_TRANSPORT_VERSION);