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 <linux/slab.h>
  26 #include <net/tcp.h>
  27 #include <scsi/scsi.h>
  28 #include <scsi/scsi_host.h>
  29 #include <scsi/scsi_device.h>
  30 #include <scsi/scsi_transport.h>
  31 #include <scsi/scsi_transport_iscsi.h>
  32 #include <scsi/iscsi_if.h>
  33 #include <scsi/scsi_cmnd.h>
  34
  35 #define ISCSI_SESSION_ATTRS 23
  36 #define ISCSI_CONN_ATTRS 13
  37 #define ISCSI_HOST_ATTRS 4
  38
  39 #define ISCSI_TRANSPORT_VERSION "2.0-870"
  40
  41 static int dbg_session;
  42 module_param_named(debug_session, dbg_session, int,
  43                    S_IRUGO | S_IWUSR);
  44 MODULE_PARM_DESC(debug_session,
  45                  "Turn on debugging for sessions in scsi_transport_iscsi "
  46                  "module. Set to 1 to turn on, and zero to turn off. Default "
  47                  "is off.");
  48
  49 static int dbg_conn;
  50 module_param_named(debug_conn, dbg_conn, int,
  51                    S_IRUGO | S_IWUSR);
  52 MODULE_PARM_DESC(debug_conn,
  53                  "Turn on debugging for connections in scsi_transport_iscsi "
  54                  "module. Set to 1 to turn on, and zero to turn off. Default "
  55                  "is off.");
  56
  57 #define ISCSI_DBG_TRANS_SESSION(_session, dbg_fmt, arg...)              \
  58         do {                                                            \
  59                 if (dbg_session)                                        \
  60                         iscsi_cls_session_printk(KERN_INFO, _session,   \
  61                                                  "%s: " dbg_fmt,        \
  62                                                  __func__, ##arg);      \
  63         } while (0);
  64
  65 #define ISCSI_DBG_TRANS_CONN(_conn, dbg_fmt, arg...)                    \
  66         do {                                                            \
  67                 if (dbg_conn)                                           \
  68                         iscsi_cls_conn_printk(KERN_INFO, _conn,         \
  69                                               "%s: " dbg_fmt,           \
  70                                               __func__, ##arg); \
  71         } while (0);
  72
  73 struct iscsi_internal {
  74         struct scsi_transport_template t;
  75         struct iscsi_transport *iscsi_transport;
  76         struct list_head list;
  77         struct device dev;
  78
  79         struct device_attribute *host_attrs[ISCSI_HOST_ATTRS + 1];
  80         struct transport_container conn_cont;
  81         struct device_attribute *conn_attrs[ISCSI_CONN_ATTRS + 1];
  82         struct transport_container session_cont;
  83         struct device_attribute *session_attrs[ISCSI_SESSION_ATTRS + 1];
  84 };
  85
  86 static atomic_t iscsi_session_nr; /* sysfs session id for next new session */
  87 static struct workqueue_struct *iscsi_eh_timer_workq;
  88
  89 /*
  90  * list of registered transports and lock that must
  91  * be held while accessing list. The iscsi_transport_lock must
  92  * be acquired after the rx_queue_mutex.
  93  */
  94 static LIST_HEAD(iscsi_transports);
  95 static DEFINE_SPINLOCK(iscsi_transport_lock);
  96
  97 #define to_iscsi_internal(tmpl) \
  98         container_of(tmpl, struct iscsi_internal, t)
  99
 100 #define dev_to_iscsi_internal(_dev) \
 101         container_of(_dev, struct iscsi_internal, dev)
 102
 103 static void iscsi_transport_release(struct device *dev)
 104 {
 105         struct iscsi_internal *priv = dev_to_iscsi_internal(dev);
 106         kfree(priv);
 107 }
 108
 109 /*
 110  * iscsi_transport_class represents the iscsi_transports that are
 111  * registered.
 112  */
 113 static struct class iscsi_transport_class = {
 114         .name = "iscsi_transport",
 115         .dev_release = iscsi_transport_release,
 116 };
 117
 118 static ssize_t
 119 show_transport_handle(struct device *dev, struct device_attribute *attr,
 120                       char *buf)
 121 {
 122         struct iscsi_internal *priv = dev_to_iscsi_internal(dev);
 123         return sprintf(buf, "%llu\n", (unsigned long long)iscsi_handle(priv->iscsi_transport));
 124 }
 125 static DEVICE_ATTR(handle, S_IRUGO, show_transport_handle, NULL);
 126
 127 #define show_transport_attr(name, format)                               \
 128 static ssize_t                                                          \
 129 show_transport_##name(struct device *dev,                               \
 130                       struct device_attribute *attr,char *buf)          \
 131 {                                                                       \
 132         struct iscsi_internal *priv = dev_to_iscsi_internal(dev);       \
 133         return sprintf(buf, format"\n", priv->iscsi_transport->name);   \
 134 }                                                                       \
 135 static DEVICE_ATTR(name, S_IRUGO, show_transport_##name, NULL);
 136
 137 show_transport_attr(caps, "0x%x");
 138
 139 static struct attribute *iscsi_transport_attrs[] = {
 140         &dev_attr_handle.attr,
 141         &dev_attr_caps.attr,
 142         NULL,
 143 };
 144
 145 static struct attribute_group iscsi_transport_group = {
 146         .attrs = iscsi_transport_attrs,
 147 };
 148
 149 /*
 150  * iSCSI endpoint attrs
 151  */
 152 #define iscsi_dev_to_endpoint(_dev) \
 153         container_of(_dev, struct iscsi_endpoint, dev)
 154
 155 #define ISCSI_ATTR(_prefix,_name,_mode,_show,_store)    \
 156 struct device_attribute dev_attr_##_prefix##_##_name =  \
 157         __ATTR(_name,_mode,_show,_store)
 158
 159 static void iscsi_endpoint_release(struct device *dev)
 160 {
 161         struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
 162         kfree(ep);
 163 }
 164
 165 static struct class iscsi_endpoint_class = {
 166         .name = "iscsi_endpoint",
 167         .dev_release = iscsi_endpoint_release,
 168 };
 169
 170 static ssize_t
 171 show_ep_handle(struct device *dev, struct device_attribute *attr, char *buf)
 172 {
 173         struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
 174         return sprintf(buf, "%llu\n", (unsigned long long) ep->id);
 175 }
 176 static ISCSI_ATTR(ep, handle, S_IRUGO, show_ep_handle, NULL);
 177
 178 static struct attribute *iscsi_endpoint_attrs[] = {
 179         &dev_attr_ep_handle.attr,
 180         NULL,
 181 };
 182
 183 static struct attribute_group iscsi_endpoint_group = {
 184         .attrs = iscsi_endpoint_attrs,
 185 };
 186
 187 #define ISCSI_MAX_EPID -1
 188
 189 static int iscsi_match_epid(struct device *dev, void *data)
 190 {
 191         struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
 192         uint64_t *epid = (uint64_t *) data;
 193
 194         return *epid == ep->id;
 195 }
 196
 197 struct iscsi_endpoint *
 198 iscsi_create_endpoint(int dd_size)
 199 {
 200         struct device *dev;
 201         struct iscsi_endpoint *ep;
 202         uint64_t id;
 203         int err;
 204
 205         for (id = 1; id < ISCSI_MAX_EPID; id++) {
 206                 dev = class_find_device(&iscsi_endpoint_class, NULL, &id,
 207                                         iscsi_match_epid);
 208                 if (!dev)
 209                         break;
 210         }
 211         if (id == ISCSI_MAX_EPID) {
 212                 printk(KERN_ERR "Too many connections. Max supported %u\n",
 213                        ISCSI_MAX_EPID - 1);
 214                 return NULL;
 215         }
 216
 217         ep = kzalloc(sizeof(*ep) + dd_size, GFP_KERNEL);
 218         if (!ep)
 219                 return NULL;
 220
 221         ep->id = id;
 222         ep->dev.class = &iscsi_endpoint_class;
 223         dev_set_name(&ep->dev, "ep-%llu", (unsigned long long) id);
 224         err = device_register(&ep->dev);
 225         if (err)
 226                 goto free_ep;
 227
 228         err = sysfs_create_group(&ep->dev.kobj, &iscsi_endpoint_group);
 229         if (err)
 230                 goto unregister_dev;
 231
 232         if (dd_size)
 233                 ep->dd_data = &ep[1];
 234         return ep;
 235
 236 unregister_dev:
 237         device_unregister(&ep->dev);
 238         return NULL;
 239
 240 free_ep:
 241         kfree(ep);
 242         return NULL;
 243 }
 244 EXPORT_SYMBOL_GPL(iscsi_create_endpoint);
 245
 246 void iscsi_destroy_endpoint(struct iscsi_endpoint *ep)
 247 {
 248         sysfs_remove_group(&ep->dev.kobj, &iscsi_endpoint_group);
 249         device_unregister(&ep->dev);
 250 }
 251 EXPORT_SYMBOL_GPL(iscsi_destroy_endpoint);
 252
 253 struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle)
 254 {
 255         struct iscsi_endpoint *ep;
 256         struct device *dev;
 257
 258         dev = class_find_device(&iscsi_endpoint_class, NULL, &handle,
 259                                 iscsi_match_epid);
 260         if (!dev)
 261                 return NULL;
 262
 263         ep = iscsi_dev_to_endpoint(dev);
 264         /*
 265          * we can drop this now because the interface will prevent
 266          * removals and lookups from racing.
 267          */
 268         put_device(dev);
 269         return ep;
 270 }
 271 EXPORT_SYMBOL_GPL(iscsi_lookup_endpoint);
 272
 273 static int iscsi_setup_host(struct transport_container *tc, struct device *dev,
 274                             struct device *cdev)
 275 {
 276         struct Scsi_Host *shost = dev_to_shost(dev);
 277         struct iscsi_cls_host *ihost = shost->shost_data;
 278
 279         memset(ihost, 0, sizeof(*ihost));
 280         atomic_set(&ihost->nr_scans, 0);
 281         mutex_init(&ihost->mutex);
 282         return 0;
 283 }
 284
 285 static DECLARE_TRANSPORT_CLASS(iscsi_host_class,
 286                                "iscsi_host",
 287                                iscsi_setup_host,
 288                                NULL,
 289                                NULL);
 290
 291 static DECLARE_TRANSPORT_CLASS(iscsi_session_class,
 292                                "iscsi_session",
 293                                NULL,
 294                                NULL,
 295                                NULL);
 296
 297 static DECLARE_TRANSPORT_CLASS(iscsi_connection_class,
 298                                "iscsi_connection",
 299                                NULL,
 300                                NULL,
 301                                NULL);
 302
 303 static struct sock *nls;
 304 static DEFINE_MUTEX(rx_queue_mutex);
 305
 306 static LIST_HEAD(sesslist);
 307 static DEFINE_SPINLOCK(sesslock);
 308 static LIST_HEAD(connlist);
 309 static DEFINE_SPINLOCK(connlock);
 310
 311 static uint32_t iscsi_conn_get_sid(struct iscsi_cls_conn *conn)
 312 {
 313         struct iscsi_cls_session *sess = iscsi_dev_to_session(conn->dev.parent);
 314         return sess->sid;
 315 }
 316
 317 /*
 318  * Returns the matching session to a given sid
 319  */
 320 static struct iscsi_cls_session *iscsi_session_lookup(uint32_t sid)
 321 {
 322         unsigned long flags;
 323         struct iscsi_cls_session *sess;
 324
 325         spin_lock_irqsave(&sesslock, flags);
 326         list_for_each_entry(sess, &sesslist, sess_list) {
 327                 if (sess->sid == sid) {
 328                         spin_unlock_irqrestore(&sesslock, flags);
 329                         return sess;
 330                 }
 331         }
 332         spin_unlock_irqrestore(&sesslock, flags);
 333         return NULL;
 334 }
 335
 336 /*
 337  * Returns the matching connection to a given sid / cid tuple
 338  */
 339 static struct iscsi_cls_conn *iscsi_conn_lookup(uint32_t sid, uint32_t cid)
 340 {
 341         unsigned long flags;
 342         struct iscsi_cls_conn *conn;
 343
 344         spin_lock_irqsave(&connlock, flags);
 345         list_for_each_entry(conn, &connlist, conn_list) {
 346                 if ((conn->cid == cid) && (iscsi_conn_get_sid(conn) == sid)) {
 347                         spin_unlock_irqrestore(&connlock, flags);
 348                         return conn;
 349                 }
 350         }
 351         spin_unlock_irqrestore(&connlock, flags);
 352         return NULL;
 353 }
 354
 355 /*
 356  * The following functions can be used by LLDs that allocate
 357  * their own scsi_hosts or by software iscsi LLDs
 358  */
 359 static struct {
 360         int value;
 361         char *name;
 362 } iscsi_session_state_names[] = {
 363         { ISCSI_SESSION_LOGGED_IN,      "LOGGED_IN" },
 364         { ISCSI_SESSION_FAILED,         "FAILED" },
 365         { ISCSI_SESSION_FREE,           "FREE" },
 366 };
 367
 368 static const char *iscsi_session_state_name(int state)
 369 {
 370         int i;
 371         char *name = NULL;
 372
 373         for (i = 0; i < ARRAY_SIZE(iscsi_session_state_names); i++) {
 374                 if (iscsi_session_state_names[i].value == state) {
 375                         name = iscsi_session_state_names[i].name;
 376                         break;
 377                 }
 378         }
 379         return name;
 380 }
 381
 382 int iscsi_session_chkready(struct iscsi_cls_session *session)
 383 {
 384         unsigned long flags;
 385         int err;
 386
 387         spin_lock_irqsave(&session->lock, flags);
 388         switch (session->state) {
 389         case ISCSI_SESSION_LOGGED_IN:
 390                 err = 0;
 391                 break;
 392         case ISCSI_SESSION_FAILED:
 393                 err = DID_IMM_RETRY << 16;
 394                 break;
 395         case ISCSI_SESSION_FREE:
 396                 err = DID_TRANSPORT_FAILFAST << 16;
 397                 break;
 398         default:
 399                 err = DID_NO_CONNECT << 16;
 400                 break;
 401         }
 402         spin_unlock_irqrestore(&session->lock, flags);
 403         return err;
 404 }
 405 EXPORT_SYMBOL_GPL(iscsi_session_chkready);
 406
 407 static void iscsi_session_release(struct device *dev)
 408 {
 409         struct iscsi_cls_session *session = iscsi_dev_to_session(dev);
 410         struct Scsi_Host *shost;
 411
 412         shost = iscsi_session_to_shost(session);
 413         scsi_host_put(shost);
 414         ISCSI_DBG_TRANS_SESSION(session, "Completing session release\n");
 415         kfree(session);
 416 }
 417
 418 static int iscsi_is_session_dev(const struct device *dev)
 419 {
 420         return dev->release == iscsi_session_release;
 421 }
 422
 423 static int iscsi_iter_session_fn(struct device *dev, void *data)
 424 {
 425         void (* fn) (struct iscsi_cls_session *) = data;
 426
 427         if (!iscsi_is_session_dev(dev))
 428                 return 0;
 429         fn(iscsi_dev_to_session(dev));
 430         return 0;
 431 }
 432
 433 void iscsi_host_for_each_session(struct Scsi_Host *shost,
 434                                  void (*fn)(struct iscsi_cls_session *))
 435 {
 436         device_for_each_child(&shost->shost_gendev, fn,
 437                               iscsi_iter_session_fn);
 438 }
 439 EXPORT_SYMBOL_GPL(iscsi_host_for_each_session);
 440
 441 /**
 442  * iscsi_scan_finished - helper to report when running scans are done
 443  * @shost: scsi host
 444  * @time: scan run time
 445  *
 446  * This function can be used by drives like qla4xxx to report to the scsi
 447  * layer when the scans it kicked off at module load time are done.
 448  */
 449 int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time)
 450 {
 451         struct iscsi_cls_host *ihost = shost->shost_data;
 452         /*
 453          * qla4xxx will have kicked off some session unblocks before calling
 454          * scsi_scan_host, so just wait for them to complete.
 455          */
 456         return !atomic_read(&ihost->nr_scans);
 457 }
 458 EXPORT_SYMBOL_GPL(iscsi_scan_finished);
 459
 460 struct iscsi_scan_data {
 461         unsigned int channel;
 462         unsigned int id;
 463         unsigned int lun;
 464 };
 465
 466 static int iscsi_user_scan_session(struct device *dev, void *data)
 467 {
 468         struct iscsi_scan_data *scan_data = data;
 469         struct iscsi_cls_session *session;
 470         struct Scsi_Host *shost;
 471         struct iscsi_cls_host *ihost;
 472         unsigned long flags;
 473         unsigned int id;
 474
 475         if (!iscsi_is_session_dev(dev))
 476                 return 0;
 477
 478         session = iscsi_dev_to_session(dev);
 479
 480         ISCSI_DBG_TRANS_SESSION(session, "Scanning session\n");
 481
 482         shost = iscsi_session_to_shost(session);
 483         ihost = shost->shost_data;
 484
 485         mutex_lock(&ihost->mutex);
 486         spin_lock_irqsave(&session->lock, flags);
 487         if (session->state != ISCSI_SESSION_LOGGED_IN) {
 488                 spin_unlock_irqrestore(&session->lock, flags);
 489                 goto user_scan_exit;
 490         }
 491         id = session->target_id;
 492         spin_unlock_irqrestore(&session->lock, flags);
 493
 494         if (id != ISCSI_MAX_TARGET) {
 495                 if ((scan_data->channel == SCAN_WILD_CARD ||
 496                      scan_data->channel == 0) &&
 497                     (scan_data->id == SCAN_WILD_CARD ||
 498                      scan_data->id == id))
 499                         scsi_scan_target(&session->dev, 0, id,
 500                                          scan_data->lun, 1);
 501         }
 502
 503 user_scan_exit:
 504         mutex_unlock(&ihost->mutex);
 505         ISCSI_DBG_TRANS_SESSION(session, "Completed session scan\n");
 506         return 0;
 507 }
 508
 509 static int iscsi_user_scan(struct Scsi_Host *shost, uint channel,
 510                            uint id, uint lun)
 511 {
 512         struct iscsi_scan_data scan_data;
 513
 514         scan_data.channel = channel;
 515         scan_data.id = id;
 516         scan_data.lun = lun;
 517
 518         return device_for_each_child(&shost->shost_gendev, &scan_data,
 519                                      iscsi_user_scan_session);
 520 }
 521
 522 static void iscsi_scan_session(struct work_struct *work)
 523 {
 524         struct iscsi_cls_session *session =
 525                         container_of(work, struct iscsi_cls_session, scan_work);
 526         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 527         struct iscsi_cls_host *ihost = shost->shost_data;
 528         struct iscsi_scan_data scan_data;
 529
 530         scan_data.channel = 0;
 531         scan_data.id = SCAN_WILD_CARD;
 532         scan_data.lun = SCAN_WILD_CARD;
 533
 534         iscsi_user_scan_session(&session->dev, &scan_data);
 535         atomic_dec(&ihost->nr_scans);
 536 }
 537
 538 /**
 539  * iscsi_block_scsi_eh - block scsi eh until session state has transistioned
 540  * @cmd: scsi cmd passed to scsi eh handler
 541  *
 542  * If the session is down this function will wait for the recovery
 543  * timer to fire or for the session to be logged back in. If the
 544  * recovery timer fires then FAST_IO_FAIL is returned. The caller
 545  * should pass this error value to the scsi eh.
 546  */
 547 int iscsi_block_scsi_eh(struct scsi_cmnd *cmd)
 548 {
 549         struct iscsi_cls_session *session =
 550                         starget_to_session(scsi_target(cmd->device));
 551         unsigned long flags;
 552         int ret = 0;
 553
 554         spin_lock_irqsave(&session->lock, flags);
 555         while (session->state != ISCSI_SESSION_LOGGED_IN) {
 556                 if (session->state == ISCSI_SESSION_FREE) {
 557                         ret = FAST_IO_FAIL;
 558                         break;
 559                 }
 560                 spin_unlock_irqrestore(&session->lock, flags);
 561                 msleep(1000);
 562                 spin_lock_irqsave(&session->lock, flags);
 563         }
 564         spin_unlock_irqrestore(&session->lock, flags);
 565         return ret;
 566 }
 567 EXPORT_SYMBOL_GPL(iscsi_block_scsi_eh);
 568
 569 static void session_recovery_timedout(struct work_struct *work)
 570 {
 571         struct iscsi_cls_session *session =
 572                 container_of(work, struct iscsi_cls_session,
 573                              recovery_work.work);
 574         unsigned long flags;
 575
 576         iscsi_cls_session_printk(KERN_INFO, session,
 577                                  "session recovery timed out after %d secs\n",
 578                                  session->recovery_tmo);
 579
 580         spin_lock_irqsave(&session->lock, flags);
 581         switch (session->state) {
 582         case ISCSI_SESSION_FAILED:
 583                 session->state = ISCSI_SESSION_FREE;
 584                 break;
 585         case ISCSI_SESSION_LOGGED_IN:
 586         case ISCSI_SESSION_FREE:
 587                 /* we raced with the unblock's flush */
 588                 spin_unlock_irqrestore(&session->lock, flags);
 589                 return;
 590         }
 591         spin_unlock_irqrestore(&session->lock, flags);
 592
 593         if (session->transport->session_recovery_timedout)
 594                 session->transport->session_recovery_timedout(session);
 595
 596         ISCSI_DBG_TRANS_SESSION(session, "Unblocking SCSI target\n");
 597         scsi_target_unblock(&session->dev);
 598         ISCSI_DBG_TRANS_SESSION(session, "Completed unblocking SCSI target\n");
 599 }
 600
 601 static void __iscsi_unblock_session(struct work_struct *work)
 602 {
 603         struct iscsi_cls_session *session =
 604                         container_of(work, struct iscsi_cls_session,
 605                                      unblock_work);
 606         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 607         struct iscsi_cls_host *ihost = shost->shost_data;
 608         unsigned long flags;
 609
 610         ISCSI_DBG_TRANS_SESSION(session, "Unblocking session\n");
 611         /*
 612          * The recovery and unblock work get run from the same workqueue,
 613          * so try to cancel it if it was going to run after this unblock.
 614          */
 615         cancel_delayed_work(&session->recovery_work);
 616         spin_lock_irqsave(&session->lock, flags);
 617         session->state = ISCSI_SESSION_LOGGED_IN;
 618         spin_unlock_irqrestore(&session->lock, flags);
 619         /* start IO */
 620         scsi_target_unblock(&session->dev);
 621         /*
 622          * Only do kernel scanning if the driver is properly hooked into
 623          * the async scanning code (drivers like iscsi_tcp do login and
 624          * scanning from userspace).
 625          */
 626         if (shost->hostt->scan_finished) {
 627                 if (scsi_queue_work(shost, &session->scan_work))
 628                         atomic_inc(&ihost->nr_scans);
 629         }
 630         ISCSI_DBG_TRANS_SESSION(session, "Completed unblocking session\n");
 631 }
 632
 633 /**
 634  * iscsi_unblock_session - set a session as logged in and start IO.
 635  * @session: iscsi session
 636  *
 637  * Mark a session as ready to accept IO.
 638  */
 639 void iscsi_unblock_session(struct iscsi_cls_session *session)
 640 {
 641         queue_work(iscsi_eh_timer_workq, &session->unblock_work);
 642         /*
 643          * make sure all the events have completed before tell the driver
 644          * it is safe
 645          */
 646         flush_workqueue(iscsi_eh_timer_workq);
 647 }
 648 EXPORT_SYMBOL_GPL(iscsi_unblock_session);
 649
 650 static void __iscsi_block_session(struct work_struct *work)
 651 {
 652         struct iscsi_cls_session *session =
 653                         container_of(work, struct iscsi_cls_session,
 654                                      block_work);
 655         unsigned long flags;
 656
 657         ISCSI_DBG_TRANS_SESSION(session, "Blocking session\n");
 658         spin_lock_irqsave(&session->lock, flags);
 659         session->state = ISCSI_SESSION_FAILED;
 660         spin_unlock_irqrestore(&session->lock, flags);
 661         scsi_target_block(&session->dev);
 662         ISCSI_DBG_TRANS_SESSION(session, "Completed SCSI target blocking\n");
 663         if (session->recovery_tmo >= 0)
 664                 queue_delayed_work(iscsi_eh_timer_workq,
 665                                    &session->recovery_work,
 666                                    session->recovery_tmo * HZ);
 667 }
 668
 669 void iscsi_block_session(struct iscsi_cls_session *session)
 670 {
 671         queue_work(iscsi_eh_timer_workq, &session->block_work);
 672 }
 673 EXPORT_SYMBOL_GPL(iscsi_block_session);
 674
 675 static void __iscsi_unbind_session(struct work_struct *work)
 676 {
 677         struct iscsi_cls_session *session =
 678                         container_of(work, struct iscsi_cls_session,
 679                                      unbind_work);
 680         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 681         struct iscsi_cls_host *ihost = shost->shost_data;
 682         unsigned long flags;
 683
 684         ISCSI_DBG_TRANS_SESSION(session, "Unbinding session\n");
 685
 686         /* Prevent new scans and make sure scanning is not in progress */
 687         mutex_lock(&ihost->mutex);
 688         spin_lock_irqsave(&session->lock, flags);
 689         if (session->target_id == ISCSI_MAX_TARGET) {
 690                 spin_unlock_irqrestore(&session->lock, flags);
 691                 mutex_unlock(&ihost->mutex);
 692                 return;
 693         }
 694         session->target_id = ISCSI_MAX_TARGET;
 695         spin_unlock_irqrestore(&session->lock, flags);
 696         mutex_unlock(&ihost->mutex);
 697
 698         scsi_remove_target(&session->dev);
 699         iscsi_session_event(session, ISCSI_KEVENT_UNBIND_SESSION);
 700         ISCSI_DBG_TRANS_SESSION(session, "Completed target removal\n");
 701 }
 702
 703 struct iscsi_cls_session *
 704 iscsi_alloc_session(struct Scsi_Host *shost, struct iscsi_transport *transport,
 705                     int dd_size)
 706 {
 707         struct iscsi_cls_session *session;
 708
 709         session = kzalloc(sizeof(*session) + dd_size,
 710                           GFP_KERNEL);
 711         if (!session)
 712                 return NULL;
 713
 714         session->transport = transport;
 715         session->recovery_tmo = 120;
 716         session->state = ISCSI_SESSION_FREE;
 717         INIT_DELAYED_WORK(&session->recovery_work, session_recovery_timedout);
 718         INIT_LIST_HEAD(&session->sess_list);
 719         INIT_WORK(&session->unblock_work, __iscsi_unblock_session);
 720         INIT_WORK(&session->block_work, __iscsi_block_session);
 721         INIT_WORK(&session->unbind_work, __iscsi_unbind_session);
 722         INIT_WORK(&session->scan_work, iscsi_scan_session);
 723         spin_lock_init(&session->lock);
 724
 725         /* this is released in the dev's release function */
 726         scsi_host_get(shost);
 727         session->dev.parent = &shost->shost_gendev;
 728         session->dev.release = iscsi_session_release;
 729         device_initialize(&session->dev);
 730         if (dd_size)
 731                 session->dd_data = &session[1];
 732
 733         ISCSI_DBG_TRANS_SESSION(session, "Completed session allocation\n");
 734         return session;
 735 }
 736 EXPORT_SYMBOL_GPL(iscsi_alloc_session);
 737
 738 static int iscsi_get_next_target_id(struct device *dev, void *data)
 739 {
 740         struct iscsi_cls_session *session;
 741         unsigned long flags;
 742         int err = 0;
 743
 744         if (!iscsi_is_session_dev(dev))
 745                 return 0;
 746
 747         session = iscsi_dev_to_session(dev);
 748         spin_lock_irqsave(&session->lock, flags);
 749         if (*((unsigned int *) data) == session->target_id)
 750                 err = -EEXIST;
 751         spin_unlock_irqrestore(&session->lock, flags);
 752         return err;
 753 }
 754
 755 int iscsi_add_session(struct iscsi_cls_session *session, unsigned int target_id)
 756 {
 757         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 758         struct iscsi_cls_host *ihost;
 759         unsigned long flags;
 760         unsigned int id = target_id;
 761         int err;
 762
 763         ihost = shost->shost_data;
 764         session->sid = atomic_add_return(1, &iscsi_session_nr);
 765
 766         if (id == ISCSI_MAX_TARGET) {
 767                 for (id = 0; id < ISCSI_MAX_TARGET; id++) {
 768                         err = device_for_each_child(&shost->shost_gendev, &id,
 769                                                     iscsi_get_next_target_id);
 770                         if (!err)
 771                                 break;
 772                 }
 773
 774                 if (id == ISCSI_MAX_TARGET) {
 775                         iscsi_cls_session_printk(KERN_ERR, session,
 776                                                  "Too many iscsi targets. Max "
 777                                                  "number of targets is %d.\n",
 778                                                  ISCSI_MAX_TARGET - 1);
 779                         err = -EOVERFLOW;
 780                         goto release_host;
 781                 }
 782         }
 783         session->target_id = id;
 784
 785         dev_set_name(&session->dev, "session%u", session->sid);
 786         err = device_add(&session->dev);
 787         if (err) {
 788                 iscsi_cls_session_printk(KERN_ERR, session,
 789                                          "could not register session's dev\n");
 790                 goto release_host;
 791         }
 792         transport_register_device(&session->dev);
 793
 794         spin_lock_irqsave(&sesslock, flags);
 795         list_add(&session->sess_list, &sesslist);
 796         spin_unlock_irqrestore(&sesslock, flags);
 797
 798         iscsi_session_event(session, ISCSI_KEVENT_CREATE_SESSION);
 799         ISCSI_DBG_TRANS_SESSION(session, "Completed session adding\n");
 800         return 0;
 801
 802 release_host:
 803         scsi_host_put(shost);
 804         return err;
 805 }
 806 EXPORT_SYMBOL_GPL(iscsi_add_session);
 807
 808 /**
 809  * iscsi_create_session - create iscsi class session
 810  * @shost: scsi host
 811  * @transport: iscsi transport
 812  * @dd_size: private driver data size
 813  * @target_id: which target
 814  *
 815  * This can be called from a LLD or iscsi_transport.
 816  */
 817 struct iscsi_cls_session *
 818 iscsi_create_session(struct Scsi_Host *shost, struct iscsi_transport *transport,
 819                      int dd_size, unsigned int target_id)
 820 {
 821         struct iscsi_cls_session *session;
 822
 823         session = iscsi_alloc_session(shost, transport, dd_size);
 824         if (!session)
 825                 return NULL;
 826
 827         if (iscsi_add_session(session, target_id)) {
 828                 iscsi_free_session(session);
 829                 return NULL;
 830         }
 831         return session;
 832 }
 833 EXPORT_SYMBOL_GPL(iscsi_create_session);
 834
 835 static void iscsi_conn_release(struct device *dev)
 836 {
 837         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev);
 838         struct device *parent = conn->dev.parent;
 839
 840         ISCSI_DBG_TRANS_CONN(conn, "Releasing conn\n");
 841         kfree(conn);
 842         put_device(parent);
 843 }
 844
 845 static int iscsi_is_conn_dev(const struct device *dev)
 846 {
 847         return dev->release == iscsi_conn_release;
 848 }
 849
 850 static int iscsi_iter_destroy_conn_fn(struct device *dev, void *data)
 851 {
 852         if (!iscsi_is_conn_dev(dev))
 853                 return 0;
 854         return iscsi_destroy_conn(iscsi_dev_to_conn(dev));
 855 }
 856
 857 void iscsi_remove_session(struct iscsi_cls_session *session)
 858 {
 859         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 860         unsigned long flags;
 861         int err;
 862
 863         ISCSI_DBG_TRANS_SESSION(session, "Removing session\n");
 864
 865         spin_lock_irqsave(&sesslock, flags);
 866         list_del(&session->sess_list);
 867         spin_unlock_irqrestore(&sesslock, flags);
 868
 869         /* make sure there are no blocks/unblocks queued */
 870         flush_workqueue(iscsi_eh_timer_workq);
 871         /* make sure the timedout callout is not running */
 872         if (!cancel_delayed_work(&session->recovery_work))
 873                 flush_workqueue(iscsi_eh_timer_workq);
 874         /*
 875          * If we are blocked let commands flow again. The lld or iscsi
 876          * layer should set up the queuecommand to fail commands.
 877          * We assume that LLD will not be calling block/unblock while
 878          * removing the session.
 879          */
 880         spin_lock_irqsave(&session->lock, flags);
 881         session->state = ISCSI_SESSION_FREE;
 882         spin_unlock_irqrestore(&session->lock, flags);
 883
 884         scsi_target_unblock(&session->dev);
 885         /* flush running scans then delete devices */
 886         scsi_flush_work(shost);
 887         __iscsi_unbind_session(&session->unbind_work);
 888
 889         /* hw iscsi may not have removed all connections from session */
 890         err = device_for_each_child(&session->dev, NULL,
 891                                     iscsi_iter_destroy_conn_fn);
 892         if (err)
 893                 iscsi_cls_session_printk(KERN_ERR, session,
 894                                          "Could not delete all connections "
 895                                          "for session. Error %d.\n", err);
 896
 897         transport_unregister_device(&session->dev);
 898
 899         ISCSI_DBG_TRANS_SESSION(session, "Completing session removal\n");
 900         device_del(&session->dev);
 901 }
 902 EXPORT_SYMBOL_GPL(iscsi_remove_session);
 903
 904 void iscsi_free_session(struct iscsi_cls_session *session)
 905 {
 906         ISCSI_DBG_TRANS_SESSION(session, "Freeing session\n");
 907         iscsi_session_event(session, ISCSI_KEVENT_DESTROY_SESSION);
 908         put_device(&session->dev);
 909 }
 910 EXPORT_SYMBOL_GPL(iscsi_free_session);
 911
 912 /**
 913  * iscsi_destroy_session - destroy iscsi session
 914  * @session: iscsi_session
 915  *
 916  * Can be called by a LLD or iscsi_transport. There must not be
 917  * any running connections.
 918  */
 919 int iscsi_destroy_session(struct iscsi_cls_session *session)
 920 {
 921         iscsi_remove_session(session);
 922         ISCSI_DBG_TRANS_SESSION(session, "Completing session destruction\n");
 923         iscsi_free_session(session);
 924         return 0;
 925 }
 926 EXPORT_SYMBOL_GPL(iscsi_destroy_session);
 927
 928 /**
 929  * iscsi_create_conn - create iscsi class connection
 930  * @session: iscsi cls session
 931  * @dd_size: private driver data size
 932  * @cid: connection id
 933  *
 934  * This can be called from a LLD or iscsi_transport. The connection
 935  * is child of the session so cid must be unique for all connections
 936  * on the session.
 937  *
 938  * Since we do not support MCS, cid will normally be zero. In some cases
 939  * for software iscsi we could be trying to preallocate a connection struct
 940  * in which case there could be two connection structs and cid would be
 941  * non-zero.
 942  */
 943 struct iscsi_cls_conn *
 944 iscsi_create_conn(struct iscsi_cls_session *session, int dd_size, uint32_t cid)
 945 {
 946         struct iscsi_transport *transport = session->transport;
 947         struct iscsi_cls_conn *conn;
 948         unsigned long flags;
 949         int err;
 950
 951         conn = kzalloc(sizeof(*conn) + dd_size, GFP_KERNEL);
 952         if (!conn)
 953                 return NULL;
 954         if (dd_size)
 955                 conn->dd_data = &conn[1];
 956
 957         mutex_init(&conn->ep_mutex);
 958         INIT_LIST_HEAD(&conn->conn_list);
 959         conn->transport = transport;
 960         conn->cid = cid;
 961
 962         /* this is released in the dev's release function */
 963         if (!get_device(&session->dev))
 964                 goto free_conn;
 965
 966         dev_set_name(&conn->dev, "connection%d:%u", session->sid, cid);
 967         conn->dev.parent = &session->dev;
 968         conn->dev.release = iscsi_conn_release;
 969         err = device_register(&conn->dev);
 970         if (err) {
 971                 iscsi_cls_session_printk(KERN_ERR, session, "could not "
 972                                          "register connection's dev\n");
 973                 goto release_parent_ref;
 974         }
 975         transport_register_device(&conn->dev);
 976
 977         spin_lock_irqsave(&connlock, flags);
 978         list_add(&conn->conn_list, &connlist);
 979         spin_unlock_irqrestore(&connlock, flags);
 980
 981         ISCSI_DBG_TRANS_CONN(conn, "Completed conn creation\n");
 982         return conn;
 983
 984 release_parent_ref:
 985         put_device(&session->dev);
 986 free_conn:
 987         kfree(conn);
 988         return NULL;
 989 }
 990
 991 EXPORT_SYMBOL_GPL(iscsi_create_conn);
 992
 993 /**
 994  * iscsi_destroy_conn - destroy iscsi class connection
 995  * @conn: iscsi cls session
 996  *
 997  * This can be called from a LLD or iscsi_transport.
 998  */
 999 int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
1000 {
1001         unsigned long flags;
1002
1003         spin_lock_irqsave(&connlock, flags);
1004         list_del(&conn->conn_list);
1005         spin_unlock_irqrestore(&connlock, flags);
1006
1007         transport_unregister_device(&conn->dev);
1008         ISCSI_DBG_TRANS_CONN(conn, "Completing conn destruction\n");
1009         device_unregister(&conn->dev);
1010         return 0;
1011 }
1012 EXPORT_SYMBOL_GPL(iscsi_destroy_conn);
1013
1014 /*
1015  * iscsi interface functions
1016  */
1017 static struct iscsi_internal *
1018 iscsi_if_transport_lookup(struct iscsi_transport *tt)
1019 {
1020         struct iscsi_internal *priv;
1021         unsigned long flags;
1022
1023         spin_lock_irqsave(&iscsi_transport_lock, flags);
1024         list_for_each_entry(priv, &iscsi_transports, list) {
1025                 if (tt == priv->iscsi_transport) {
1026                         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1027                         return priv;
1028                 }
1029         }
1030         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1031         return NULL;
1032 }
1033
1034 static int
1035 iscsi_multicast_skb(struct sk_buff *skb, uint32_t group, gfp_t gfp)
1036 {
1037         return nlmsg_multicast(nls, skb, 0, group, gfp);
1038 }
1039
1040 int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
1041                    char *data, uint32_t data_size)
1042 {
1043         struct nlmsghdr *nlh;
1044         struct sk_buff *skb;
1045         struct iscsi_uevent *ev;
1046         char *pdu;
1047         struct iscsi_internal *priv;
1048         int len = NLMSG_SPACE(sizeof(*ev) + sizeof(struct iscsi_hdr) +
1049                               data_size);
1050
1051         priv = iscsi_if_transport_lookup(conn->transport);
1052         if (!priv)
1053                 return -EINVAL;
1054
1055         skb = alloc_skb(len, GFP_ATOMIC);
1056         if (!skb) {
1057                 iscsi_conn_error_event(conn, ISCSI_ERR_CONN_FAILED);
1058                 iscsi_cls_conn_printk(KERN_ERR, conn, "can not deliver "
1059                                       "control PDU: OOM\n");
1060                 return -ENOMEM;
1061         }
1062
1063         nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1064         ev = NLMSG_DATA(nlh);
1065         memset(ev, 0, sizeof(*ev));
1066         ev->transport_handle = iscsi_handle(conn->transport);
1067         ev->type = ISCSI_KEVENT_RECV_PDU;
1068         ev->r.recv_req.cid = conn->cid;
1069         ev->r.recv_req.sid = iscsi_conn_get_sid(conn);
1070         pdu = (char*)ev + sizeof(*ev);
1071         memcpy(pdu, hdr, sizeof(struct iscsi_hdr));
1072         memcpy(pdu + sizeof(struct iscsi_hdr), data, data_size);
1073
1074         return iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_ATOMIC);
1075 }
1076 EXPORT_SYMBOL_GPL(iscsi_recv_pdu);
1077
1078 int iscsi_offload_mesg(struct Scsi_Host *shost,
1079                        struct iscsi_transport *transport, uint32_t type,
1080                        char *data, uint16_t data_size)
1081 {
1082         struct nlmsghdr *nlh;
1083         struct sk_buff *skb;
1084         struct iscsi_uevent *ev;
1085         int len = NLMSG_SPACE(sizeof(*ev) + data_size);
1086
1087         skb = alloc_skb(len, GFP_ATOMIC);
1088         if (!skb) {
1089                 printk(KERN_ERR "can not deliver iscsi offload message:OOM\n");
1090                 return -ENOMEM;
1091         }
1092
1093         nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1094         ev = NLMSG_DATA(nlh);
1095         memset(ev, 0, sizeof(*ev));
1096         ev->type = type;
1097         ev->transport_handle = iscsi_handle(transport);
1098         switch (type) {
1099         case ISCSI_KEVENT_PATH_REQ:
1100                 ev->r.req_path.host_no = shost->host_no;
1101                 break;
1102         case ISCSI_KEVENT_IF_DOWN:
1103                 ev->r.notify_if_down.host_no = shost->host_no;
1104                 break;
1105         }
1106
1107         memcpy((char *)ev + sizeof(*ev), data, data_size);
1108
1109         return iscsi_multicast_skb(skb, ISCSI_NL_GRP_UIP, GFP_ATOMIC);
1110 }
1111 EXPORT_SYMBOL_GPL(iscsi_offload_mesg);
1112
1113 void iscsi_conn_error_event(struct iscsi_cls_conn *conn, enum iscsi_err error)
1114 {
1115         struct nlmsghdr *nlh;
1116         struct sk_buff  *skb;
1117         struct iscsi_uevent *ev;
1118         struct iscsi_internal *priv;
1119         int len = NLMSG_SPACE(sizeof(*ev));
1120
1121         priv = iscsi_if_transport_lookup(conn->transport);
1122         if (!priv)
1123                 return;
1124
1125         skb = alloc_skb(len, GFP_ATOMIC);
1126         if (!skb) {
1127                 iscsi_cls_conn_printk(KERN_ERR, conn, "gracefully ignored "
1128                                       "conn error (%d)\n", error);
1129                 return;
1130         }
1131
1132         nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1133         ev = NLMSG_DATA(nlh);
1134         ev->transport_handle = iscsi_handle(conn->transport);
1135         ev->type = ISCSI_KEVENT_CONN_ERROR;
1136         ev->r.connerror.error = error;
1137         ev->r.connerror.cid = conn->cid;
1138         ev->r.connerror.sid = iscsi_conn_get_sid(conn);
1139
1140         iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_ATOMIC);
1141
1142         iscsi_cls_conn_printk(KERN_INFO, conn, "detected conn error (%d)\n",
1143                               error);
1144 }
1145 EXPORT_SYMBOL_GPL(iscsi_conn_error_event);
1146
1147 static int
1148 iscsi_if_send_reply(uint32_t group, int seq, int type, int done, int multi,
1149                     void *payload, int size)
1150 {
1151         struct sk_buff  *skb;
1152         struct nlmsghdr *nlh;
1153         int len = NLMSG_SPACE(size);
1154         int flags = multi ? NLM_F_MULTI : 0;
1155         int t = done ? NLMSG_DONE : type;
1156
1157         skb = alloc_skb(len, GFP_ATOMIC);
1158         if (!skb) {
1159                 printk(KERN_ERR "Could not allocate skb to send reply.\n");
1160                 return -ENOMEM;
1161         }
1162
1163         nlh = __nlmsg_put(skb, 0, 0, t, (len - sizeof(*nlh)), 0);
1164         nlh->nlmsg_flags = flags;
1165         memcpy(NLMSG_DATA(nlh), payload, size);
1166         return iscsi_multicast_skb(skb, group, GFP_ATOMIC);
1167 }
1168
1169 static int
1170 iscsi_if_get_stats(struct iscsi_transport *transport, struct nlmsghdr *nlh)
1171 {
1172         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1173         struct iscsi_stats *stats;
1174         struct sk_buff *skbstat;
1175         struct iscsi_cls_conn *conn;
1176         struct nlmsghdr *nlhstat;
1177         struct iscsi_uevent *evstat;
1178         struct iscsi_internal *priv;
1179         int len = NLMSG_SPACE(sizeof(*ev) +
1180                               sizeof(struct iscsi_stats) +
1181                               sizeof(struct iscsi_stats_custom) *
1182                               ISCSI_STATS_CUSTOM_MAX);
1183         int err = 0;
1184
1185         priv = iscsi_if_transport_lookup(transport);
1186         if (!priv)
1187                 return -EINVAL;
1188
1189         conn = iscsi_conn_lookup(ev->u.get_stats.sid, ev->u.get_stats.cid);
1190         if (!conn)
1191                 return -EEXIST;
1192
1193         do {
1194                 int actual_size;
1195
1196                 skbstat = alloc_skb(len, GFP_ATOMIC);
1197                 if (!skbstat) {
1198                         iscsi_cls_conn_printk(KERN_ERR, conn, "can not "
1199                                               "deliver stats: OOM\n");
1200                         return -ENOMEM;
1201                 }
1202
1203                 nlhstat = __nlmsg_put(skbstat, 0, 0, 0,
1204                                       (len - sizeof(*nlhstat)), 0);
1205                 evstat = NLMSG_DATA(nlhstat);
1206                 memset(evstat, 0, sizeof(*evstat));
1207                 evstat->transport_handle = iscsi_handle(conn->transport);
1208                 evstat->type = nlh->nlmsg_type;
1209                 evstat->u.get_stats.cid =
1210                         ev->u.get_stats.cid;
1211                 evstat->u.get_stats.sid =
1212                         ev->u.get_stats.sid;
1213                 stats = (struct iscsi_stats *)
1214                         ((char*)evstat + sizeof(*evstat));
1215                 memset(stats, 0, sizeof(*stats));
1216
1217                 transport->get_stats(conn, stats);
1218                 actual_size = NLMSG_SPACE(sizeof(struct iscsi_uevent) +
1219                                           sizeof(struct iscsi_stats) +
1220                                           sizeof(struct iscsi_stats_custom) *
1221                                           stats->custom_length);
1222                 actual_size -= sizeof(*nlhstat);
1223                 actual_size = NLMSG_LENGTH(actual_size);
1224                 skb_trim(skbstat, NLMSG_ALIGN(actual_size));
1225                 nlhstat->nlmsg_len = actual_size;
1226
1227                 err = iscsi_multicast_skb(skbstat, ISCSI_NL_GRP_ISCSID,
1228                                           GFP_ATOMIC);
1229         } while (err < 0 && err != -ECONNREFUSED);
1230
1231         return err;
1232 }
1233
1234 /**
1235  * iscsi_session_event - send session destr. completion event
1236  * @session: iscsi class session
1237  * @event: type of event
1238  */
1239 int iscsi_session_event(struct iscsi_cls_session *session,
1240                         enum iscsi_uevent_e event)
1241 {
1242         struct iscsi_internal *priv;
1243         struct Scsi_Host *shost;
1244         struct iscsi_uevent *ev;
1245         struct sk_buff  *skb;
1246         struct nlmsghdr *nlh;
1247         int rc, len = NLMSG_SPACE(sizeof(*ev));
1248
1249         priv = iscsi_if_transport_lookup(session->transport);
1250         if (!priv)
1251                 return -EINVAL;
1252         shost = iscsi_session_to_shost(session);
1253
1254         skb = alloc_skb(len, GFP_KERNEL);
1255         if (!skb) {
1256                 iscsi_cls_session_printk(KERN_ERR, session,
1257                                          "Cannot notify userspace of session "
1258                                          "event %u\n", event);
1259                 return -ENOMEM;
1260         }
1261
1262         nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1263         ev = NLMSG_DATA(nlh);
1264         ev->transport_handle = iscsi_handle(session->transport);
1265
1266         ev->type = event;
1267         switch (event) {
1268         case ISCSI_KEVENT_DESTROY_SESSION:
1269                 ev->r.d_session.host_no = shost->host_no;
1270                 ev->r.d_session.sid = session->sid;
1271                 break;
1272         case ISCSI_KEVENT_CREATE_SESSION:
1273                 ev->r.c_session_ret.host_no = shost->host_no;
1274                 ev->r.c_session_ret.sid = session->sid;
1275                 break;
1276         case ISCSI_KEVENT_UNBIND_SESSION:
1277                 ev->r.unbind_session.host_no = shost->host_no;
1278                 ev->r.unbind_session.sid = session->sid;
1279                 break;
1280         default:
1281                 iscsi_cls_session_printk(KERN_ERR, session, "Invalid event "
1282                                          "%u.\n", event);
1283                 kfree_skb(skb);
1284                 return -EINVAL;
1285         }
1286
1287         /*
1288          * this will occur if the daemon is not up, so we just warn
1289          * the user and when the daemon is restarted it will handle it
1290          */
1291         rc = iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_KERNEL);
1292         if (rc == -ESRCH)
1293                 iscsi_cls_session_printk(KERN_ERR, session,
1294                                          "Cannot notify userspace of session "
1295                                          "event %u. Check iscsi daemon\n",
1296                                          event);
1297
1298         ISCSI_DBG_TRANS_SESSION(session, "Completed handling event %d rc %d\n",
1299                                 event, rc);
1300         return rc;
1301 }
1302 EXPORT_SYMBOL_GPL(iscsi_session_event);
1303
1304 static int
1305 iscsi_if_create_session(struct iscsi_internal *priv, struct iscsi_endpoint *ep,
1306                         struct iscsi_uevent *ev, uint32_t initial_cmdsn,
1307                         uint16_t cmds_max, uint16_t queue_depth)
1308 {
1309         struct iscsi_transport *transport = priv->iscsi_transport;
1310         struct iscsi_cls_session *session;
1311         struct Scsi_Host *shost;
1312
1313         session = transport->create_session(ep, cmds_max, queue_depth,
1314                                             initial_cmdsn);
1315         if (!session)
1316                 return -ENOMEM;
1317
1318         shost = iscsi_session_to_shost(session);
1319         ev->r.c_session_ret.host_no = shost->host_no;
1320         ev->r.c_session_ret.sid = session->sid;
1321         ISCSI_DBG_TRANS_SESSION(session,
1322                                 "Completed creating transport session\n");
1323         return 0;
1324 }
1325
1326 static int
1327 iscsi_if_create_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1328 {
1329         struct iscsi_cls_conn *conn;
1330         struct iscsi_cls_session *session;
1331
1332         session = iscsi_session_lookup(ev->u.c_conn.sid);
1333         if (!session) {
1334                 printk(KERN_ERR "iscsi: invalid session %d.\n",
1335                        ev->u.c_conn.sid);
1336                 return -EINVAL;
1337         }
1338
1339         conn = transport->create_conn(session, ev->u.c_conn.cid);
1340         if (!conn) {
1341                 iscsi_cls_session_printk(KERN_ERR, session,
1342                                          "couldn't create a new connection.");
1343                 return -ENOMEM;
1344         }
1345
1346         ev->r.c_conn_ret.sid = session->sid;
1347         ev->r.c_conn_ret.cid = conn->cid;
1348
1349         ISCSI_DBG_TRANS_CONN(conn, "Completed creating transport conn\n");
1350         return 0;
1351 }
1352
1353 static int
1354 iscsi_if_destroy_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1355 {
1356         struct iscsi_cls_conn *conn;
1357
1358         conn = iscsi_conn_lookup(ev->u.d_conn.sid, ev->u.d_conn.cid);
1359         if (!conn)
1360                 return -EINVAL;
1361
1362         ISCSI_DBG_TRANS_CONN(conn, "Destroying transport conn\n");
1363         if (transport->destroy_conn)
1364                 transport->destroy_conn(conn);
1365
1366         return 0;
1367 }
1368
1369 static int
1370 iscsi_set_param(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1371 {
1372         char *data = (char*)ev + sizeof(*ev);
1373         struct iscsi_cls_conn *conn;
1374         struct iscsi_cls_session *session;
1375         int err = 0, value = 0;
1376
1377         session = iscsi_session_lookup(ev->u.set_param.sid);
1378         conn = iscsi_conn_lookup(ev->u.set_param.sid, ev->u.set_param.cid);
1379         if (!conn || !session)
1380                 return -EINVAL;
1381
1382         switch (ev->u.set_param.param) {
1383         case ISCSI_PARAM_SESS_RECOVERY_TMO:
1384                 sscanf(data, "%d", &value);
1385                 session->recovery_tmo = value;
1386                 break;
1387         default:
1388                 err = transport->set_param(conn, ev->u.set_param.param,
1389                                            data, ev->u.set_param.len);
1390         }
1391
1392         return err;
1393 }
1394
1395 static int iscsi_if_ep_connect(struct iscsi_transport *transport,
1396                                struct iscsi_uevent *ev, int msg_type)
1397 {
1398         struct iscsi_endpoint *ep;
1399         struct sockaddr *dst_addr;
1400         struct Scsi_Host *shost = NULL;
1401         int non_blocking, err = 0;
1402
1403         if (!transport->ep_connect)
1404                 return -EINVAL;
1405
1406         if (msg_type == ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST) {
1407                 shost = scsi_host_lookup(ev->u.ep_connect_through_host.host_no);
1408                 if (!shost) {
1409                         printk(KERN_ERR "ep connect failed. Could not find "
1410                                "host no %u\n",
1411                                ev->u.ep_connect_through_host.host_no);
1412                         return -ENODEV;
1413                 }
1414                 non_blocking = ev->u.ep_connect_through_host.non_blocking;
1415         } else
1416                 non_blocking = ev->u.ep_connect.non_blocking;
1417
1418         dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1419         ep = transport->ep_connect(shost, dst_addr, non_blocking);
1420         if (IS_ERR(ep)) {
1421                 err = PTR_ERR(ep);
1422                 goto release_host;
1423         }
1424
1425         ev->r.ep_connect_ret.handle = ep->id;
1426 release_host:
1427         if (shost)
1428                 scsi_host_put(shost);
1429         return err;
1430 }
1431
1432 static int iscsi_if_ep_disconnect(struct iscsi_transport *transport,
1433                                   u64 ep_handle)
1434 {
1435         struct iscsi_cls_conn *conn;
1436         struct iscsi_endpoint *ep;
1437
1438         if (!transport->ep_disconnect)
1439                 return -EINVAL;
1440
1441         ep = iscsi_lookup_endpoint(ep_handle);
1442         if (!ep)
1443                 return -EINVAL;
1444         conn = ep->conn;
1445         if (conn) {
1446                 mutex_lock(&conn->ep_mutex);
1447                 conn->ep = NULL;
1448                 mutex_unlock(&conn->ep_mutex);
1449         }
1450
1451         transport->ep_disconnect(ep);
1452         return 0;
1453 }
1454
1455 static int
1456 iscsi_if_transport_ep(struct iscsi_transport *transport,
1457                       struct iscsi_uevent *ev, int msg_type)
1458 {
1459         struct iscsi_endpoint *ep;
1460         int rc = 0;
1461
1462         switch (msg_type) {
1463         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST:
1464         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1465                 rc = iscsi_if_ep_connect(transport, ev, msg_type);
1466                 break;
1467         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1468                 if (!transport->ep_poll)
1469                         return -EINVAL;
1470
1471                 ep = iscsi_lookup_endpoint(ev->u.ep_poll.ep_handle);
1472                 if (!ep)
1473                         return -EINVAL;
1474
1475                 ev->r.retcode = transport->ep_poll(ep,
1476                                                    ev->u.ep_poll.timeout_ms);
1477                 break;
1478         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1479                 rc = iscsi_if_ep_disconnect(transport,
1480                                             ev->u.ep_disconnect.ep_handle);
1481                 break;
1482         }
1483         return rc;
1484 }
1485
1486 static int
1487 iscsi_tgt_dscvr(struct iscsi_transport *transport,
1488                 struct iscsi_uevent *ev)
1489 {
1490         struct Scsi_Host *shost;
1491         struct sockaddr *dst_addr;
1492         int err;
1493
1494         if (!transport->tgt_dscvr)
1495                 return -EINVAL;
1496
1497         shost = scsi_host_lookup(ev->u.tgt_dscvr.host_no);
1498         if (!shost) {
1499                 printk(KERN_ERR "target discovery could not find host no %u\n",
1500                        ev->u.tgt_dscvr.host_no);
1501                 return -ENODEV;
1502         }
1503
1504
1505         dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1506         err = transport->tgt_dscvr(shost, ev->u.tgt_dscvr.type,
1507                                    ev->u.tgt_dscvr.enable, dst_addr);
1508         scsi_host_put(shost);
1509         return err;
1510 }
1511
1512 static int
1513 iscsi_set_host_param(struct iscsi_transport *transport,
1514                      struct iscsi_uevent *ev)
1515 {
1516         char *data = (char*)ev + sizeof(*ev);
1517         struct Scsi_Host *shost;
1518         int err;
1519
1520         if (!transport->set_host_param)
1521                 return -ENOSYS;
1522
1523         shost = scsi_host_lookup(ev->u.set_host_param.host_no);
1524         if (!shost) {
1525                 printk(KERN_ERR "set_host_param could not find host no %u\n",
1526                        ev->u.set_host_param.host_no);
1527                 return -ENODEV;
1528         }
1529
1530         err = transport->set_host_param(shost, ev->u.set_host_param.param,
1531                                         data, ev->u.set_host_param.len);
1532         scsi_host_put(shost);
1533         return err;
1534 }
1535
1536 static int
1537 iscsi_set_path(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1538 {
1539         struct Scsi_Host *shost;
1540         struct iscsi_path *params;
1541         int err;
1542
1543         if (!transport->set_path)
1544                 return -ENOSYS;
1545
1546         shost = scsi_host_lookup(ev->u.set_path.host_no);
1547         if (!shost) {
1548                 printk(KERN_ERR "set path could not find host no %u\n",
1549                        ev->u.set_path.host_no);
1550                 return -ENODEV;
1551         }
1552
1553         params = (struct iscsi_path *)((char *)ev + sizeof(*ev));
1554         err = transport->set_path(shost, params);
1555
1556         scsi_host_put(shost);
1557         return err;
1558 }
1559
1560 static int
1561 iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, uint32_t *group)
1562 {
1563         int err = 0;
1564         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1565         struct iscsi_transport *transport = NULL;
1566         struct iscsi_internal *priv;
1567         struct iscsi_cls_session *session;
1568         struct iscsi_cls_conn *conn;
1569         struct iscsi_endpoint *ep = NULL;
1570
1571         if (nlh->nlmsg_type == ISCSI_UEVENT_PATH_UPDATE)
1572                 *group = ISCSI_NL_GRP_UIP;
1573         else
1574                 *group = ISCSI_NL_GRP_ISCSID;
1575
1576         priv = iscsi_if_transport_lookup(iscsi_ptr(ev->transport_handle));
1577         if (!priv)
1578                 return -EINVAL;
1579         transport = priv->iscsi_transport;
1580
1581         if (!try_module_get(transport->owner))
1582                 return -EINVAL;
1583
1584         switch (nlh->nlmsg_type) {
1585         case ISCSI_UEVENT_CREATE_SESSION:
1586                 err = iscsi_if_create_session(priv, ep, ev,
1587                                               ev->u.c_session.initial_cmdsn,
1588                                               ev->u.c_session.cmds_max,
1589                                               ev->u.c_session.queue_depth);
1590                 break;
1591         case ISCSI_UEVENT_CREATE_BOUND_SESSION:
1592                 ep = iscsi_lookup_endpoint(ev->u.c_bound_session.ep_handle);
1593                 if (!ep) {
1594                         err = -EINVAL;
1595                         break;
1596                 }
1597
1598                 err = iscsi_if_create_session(priv, ep, ev,
1599                                         ev->u.c_bound_session.initial_cmdsn,
1600                                         ev->u.c_bound_session.cmds_max,
1601                                         ev->u.c_bound_session.queue_depth);
1602                 break;
1603         case ISCSI_UEVENT_DESTROY_SESSION:
1604                 session = iscsi_session_lookup(ev->u.d_session.sid);
1605                 if (session)
1606                         transport->destroy_session(session);
1607                 else
1608                         err = -EINVAL;
1609                 break;
1610         case ISCSI_UEVENT_UNBIND_SESSION:
1611                 session = iscsi_session_lookup(ev->u.d_session.sid);
1612                 if (session)
1613                         scsi_queue_work(iscsi_session_to_shost(session),
1614                                         &session->unbind_work);
1615                 else
1616                         err = -EINVAL;
1617                 break;
1618         case ISCSI_UEVENT_CREATE_CONN:
1619                 err = iscsi_if_create_conn(transport, ev);
1620                 break;
1621         case ISCSI_UEVENT_DESTROY_CONN:
1622                 err = iscsi_if_destroy_conn(transport, ev);
1623                 break;
1624         case ISCSI_UEVENT_BIND_CONN:
1625                 session = iscsi_session_lookup(ev->u.b_conn.sid);
1626                 conn = iscsi_conn_lookup(ev->u.b_conn.sid, ev->u.b_conn.cid);
1627
1628                 if (conn && conn->ep)
1629                         iscsi_if_ep_disconnect(transport, conn->ep->id);
1630
1631                 if (!session || !conn) {
1632                         err = -EINVAL;
1633                         break;
1634                 }
1635
1636                 ev->r.retcode = transport->bind_conn(session, conn,
1637                                                 ev->u.b_conn.transport_eph,
1638                                                 ev->u.b_conn.is_leading);
1639                 if (ev->r.retcode || !transport->ep_connect)
1640                         break;
1641
1642                 ep = iscsi_lookup_endpoint(ev->u.b_conn.transport_eph);
1643                 if (ep) {
1644                         ep->conn = conn;
1645
1646                         mutex_lock(&conn->ep_mutex);
1647                         conn->ep = ep;
1648                         mutex_unlock(&conn->ep_mutex);
1649                 } else
1650                         iscsi_cls_conn_printk(KERN_ERR, conn,
1651                                               "Could not set ep conn "
1652                                               "binding\n");
1653                 break;
1654         case ISCSI_UEVENT_SET_PARAM:
1655                 err = iscsi_set_param(transport, ev);
1656                 break;
1657         case ISCSI_UEVENT_START_CONN:
1658                 conn = iscsi_conn_lookup(ev->u.start_conn.sid, ev->u.start_conn.cid);
1659                 if (conn)
1660                         ev->r.retcode = transport->start_conn(conn);
1661                 else
1662                         err = -EINVAL;
1663                 break;
1664         case ISCSI_UEVENT_STOP_CONN:
1665                 conn = iscsi_conn_lookup(ev->u.stop_conn.sid, ev->u.stop_conn.cid);
1666                 if (conn)
1667                         transport->stop_conn(conn, ev->u.stop_conn.flag);
1668                 else
1669                         err = -EINVAL;
1670                 break;
1671         case ISCSI_UEVENT_SEND_PDU:
1672                 conn = iscsi_conn_lookup(ev->u.send_pdu.sid, ev->u.send_pdu.cid);
1673                 if (conn)
1674                         ev->r.retcode = transport->send_pdu(conn,
1675                                 (struct iscsi_hdr*)((char*)ev + sizeof(*ev)),
1676                                 (char*)ev + sizeof(*ev) + ev->u.send_pdu.hdr_size,
1677                                 ev->u.send_pdu.data_size);
1678                 else
1679                         err = -EINVAL;
1680                 break;
1681         case ISCSI_UEVENT_GET_STATS:
1682                 err = iscsi_if_get_stats(transport, nlh);
1683                 break;
1684         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1685         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1686         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1687         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST:
1688                 err = iscsi_if_transport_ep(transport, ev, nlh->nlmsg_type);
1689                 break;
1690         case ISCSI_UEVENT_TGT_DSCVR:
1691                 err = iscsi_tgt_dscvr(transport, ev);
1692                 break;
1693         case ISCSI_UEVENT_SET_HOST_PARAM:
1694                 err = iscsi_set_host_param(transport, ev);
1695                 break;
1696         case ISCSI_UEVENT_PATH_UPDATE:
1697                 err = iscsi_set_path(transport, ev);
1698                 break;
1699         default:
1700                 err = -ENOSYS;
1701                 break;
1702         }
1703
1704         module_put(transport->owner);
1705         return err;
1706 }
1707
1708 /*
1709  * Get message from skb.  Each message is processed by iscsi_if_recv_msg.
1710  * Malformed skbs with wrong lengths or invalid creds are not processed.
1711  */
1712 static void
1713 iscsi_if_rx(struct sk_buff *skb)
1714 {
1715         mutex_lock(&rx_queue_mutex);
1716         while (skb->len >= NLMSG_SPACE(0)) {
1717                 int err;
1718                 uint32_t rlen;
1719                 struct nlmsghdr *nlh;
1720                 struct iscsi_uevent *ev;
1721                 uint32_t group;
1722
1723                 nlh = nlmsg_hdr(skb);
1724                 if (nlh->nlmsg_len < sizeof(*nlh) ||
1725                     skb->len < nlh->nlmsg_len) {
1726                         break;
1727                 }
1728
1729                 ev = NLMSG_DATA(nlh);
1730                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1731                 if (rlen > skb->len)
1732                         rlen = skb->len;
1733
1734                 err = iscsi_if_recv_msg(skb, nlh, &group);
1735                 if (err) {
1736                         ev->type = ISCSI_KEVENT_IF_ERROR;
1737                         ev->iferror = err;
1738                 }
1739                 do {
1740                         /*
1741                          * special case for GET_STATS:
1742                          * on success - sending reply and stats from
1743                          * inside of if_recv_msg(),
1744                          * on error - fall through.
1745                          */
1746                         if (ev->type == ISCSI_UEVENT_GET_STATS && !err)
1747                                 break;
1748                         err = iscsi_if_send_reply(group, nlh->nlmsg_seq,
1749                                 nlh->nlmsg_type, 0, 0, ev, sizeof(*ev));
1750                 } while (err < 0 && err != -ECONNREFUSED);
1751                 skb_pull(skb, rlen);
1752         }
1753         mutex_unlock(&rx_queue_mutex);
1754 }
1755
1756 #define ISCSI_CLASS_ATTR(_prefix,_name,_mode,_show,_store)              \
1757 struct device_attribute dev_attr_##_prefix##_##_name =  \
1758         __ATTR(_name,_mode,_show,_store)
1759
1760 /*
1761  * iSCSI connection attrs
1762  */
1763 #define iscsi_conn_attr_show(param)                                     \
1764 static ssize_t                                                          \
1765 show_conn_param_##param(struct device *dev,                             \
1766                         struct device_attribute *attr, char *buf)       \
1767 {                                                                       \
1768         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev->parent);   \
1769         struct iscsi_transport *t = conn->transport;                    \
1770         return t->get_conn_param(conn, param, buf);                     \
1771 }
1772
1773 #define iscsi_conn_attr(field, param)                                   \
1774         iscsi_conn_attr_show(param)                                     \
1775 static ISCSI_CLASS_ATTR(conn, field, S_IRUGO, show_conn_param_##param,  \
1776                         NULL);
1777
1778 iscsi_conn_attr(max_recv_dlength, ISCSI_PARAM_MAX_RECV_DLENGTH);
1779 iscsi_conn_attr(max_xmit_dlength, ISCSI_PARAM_MAX_XMIT_DLENGTH);
1780 iscsi_conn_attr(header_digest, ISCSI_PARAM_HDRDGST_EN);
1781 iscsi_conn_attr(data_digest, ISCSI_PARAM_DATADGST_EN);
1782 iscsi_conn_attr(ifmarker, ISCSI_PARAM_IFMARKER_EN);
1783 iscsi_conn_attr(ofmarker, ISCSI_PARAM_OFMARKER_EN);
1784 iscsi_conn_attr(persistent_port, ISCSI_PARAM_PERSISTENT_PORT);
1785 iscsi_conn_attr(exp_statsn, ISCSI_PARAM_EXP_STATSN);
1786 iscsi_conn_attr(persistent_address, ISCSI_PARAM_PERSISTENT_ADDRESS);
1787 iscsi_conn_attr(ping_tmo, ISCSI_PARAM_PING_TMO);
1788 iscsi_conn_attr(recv_tmo, ISCSI_PARAM_RECV_TMO);
1789
1790 #define iscsi_conn_ep_attr_show(param)                                  \
1791 static ssize_t show_conn_ep_param_##param(struct device *dev,           \
1792                                           struct device_attribute *attr,\
1793                                           char *buf)                    \
1794 {                                                                       \
1795         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev->parent);   \
1796         struct iscsi_transport *t = conn->transport;                    \
1797         struct iscsi_endpoint *ep;                                      \
1798         ssize_t rc;                                                     \
1799                                                                         \
1800         /*                                                              \
1801          * Need to make sure ep_disconnect does not free the LLD's      \
1802          * interconnect resources while we are trying to read them.     \
1803          */                                                             \
1804         mutex_lock(&conn->ep_mutex);                                    \
1805         ep = conn->ep;                                                  \
1806         if (!ep && t->ep_connect) {                                     \
1807                 mutex_unlock(&conn->ep_mutex);                          \
1808                 return -ENOTCONN;                                       \
1809         }                                                               \
1810                                                                         \
1811         if (ep)                                                         \
1812                 rc = t->get_ep_param(ep, param, buf);                   \
1813         else                                                            \
1814                 rc = t->get_conn_param(conn, param, buf);               \
1815         mutex_unlock(&conn->ep_mutex);                                  \
1816         return rc;                                                      \
1817 }
1818
1819 #define iscsi_conn_ep_attr(field, param)                                \
1820         iscsi_conn_ep_attr_show(param)                                  \
1821 static ISCSI_CLASS_ATTR(conn, field, S_IRUGO,                           \
1822                         show_conn_ep_param_##param, NULL);
1823
1824 iscsi_conn_ep_attr(address, ISCSI_PARAM_CONN_ADDRESS);
1825 iscsi_conn_ep_attr(port, ISCSI_PARAM_CONN_PORT);
1826
1827 /*
1828  * iSCSI session attrs
1829  */
1830 #define iscsi_session_attr_show(param, perm)                            \
1831 static ssize_t                                                          \
1832 show_session_param_##param(struct device *dev,                          \
1833                            struct device_attribute *attr, char *buf)    \
1834 {                                                                       \
1835         struct iscsi_cls_session *session =                             \
1836                 iscsi_dev_to_session(dev->parent);                      \
1837         struct iscsi_transport *t = session->transport;                 \
1838                                                                         \
1839         if (perm && !capable(CAP_SYS_ADMIN))                            \
1840                 return -EACCES;                                         \
1841         return t->get_session_param(session, param, buf);               \
1842 }
1843
1844 #define iscsi_session_attr(field, param, perm)                          \
1845         iscsi_session_attr_show(param, perm)                            \
1846 static ISCSI_CLASS_ATTR(sess, field, S_IRUGO, show_session_param_##param, \
1847                         NULL);
1848
1849 iscsi_session_attr(targetname, ISCSI_PARAM_TARGET_NAME, 0);
1850 iscsi_session_attr(initial_r2t, ISCSI_PARAM_INITIAL_R2T_EN, 0);
1851 iscsi_session_attr(max_outstanding_r2t, ISCSI_PARAM_MAX_R2T, 0);
1852 iscsi_session_attr(immediate_data, ISCSI_PARAM_IMM_DATA_EN, 0);
1853 iscsi_session_attr(first_burst_len, ISCSI_PARAM_FIRST_BURST, 0);
1854 iscsi_session_attr(max_burst_len, ISCSI_PARAM_MAX_BURST, 0);
1855 iscsi_session_attr(data_pdu_in_order, ISCSI_PARAM_PDU_INORDER_EN, 0);
1856 iscsi_session_attr(data_seq_in_order, ISCSI_PARAM_DATASEQ_INORDER_EN, 0);
1857 iscsi_session_attr(erl, ISCSI_PARAM_ERL, 0);
1858 iscsi_session_attr(tpgt, ISCSI_PARAM_TPGT, 0);
1859 iscsi_session_attr(username, ISCSI_PARAM_USERNAME, 1);
1860 iscsi_session_attr(username_in, ISCSI_PARAM_USERNAME_IN, 1);
1861 iscsi_session_attr(password, ISCSI_PARAM_PASSWORD, 1);
1862 iscsi_session_attr(password_in, ISCSI_PARAM_PASSWORD_IN, 1);
1863 iscsi_session_attr(fast_abort, ISCSI_PARAM_FAST_ABORT, 0);
1864 iscsi_session_attr(abort_tmo, ISCSI_PARAM_ABORT_TMO, 0);
1865 iscsi_session_attr(lu_reset_tmo, ISCSI_PARAM_LU_RESET_TMO, 0);
1866 iscsi_session_attr(tgt_reset_tmo, ISCSI_PARAM_TGT_RESET_TMO, 0);
1867 iscsi_session_attr(ifacename, ISCSI_PARAM_IFACE_NAME, 0);
1868 iscsi_session_attr(initiatorname, ISCSI_PARAM_INITIATOR_NAME, 0);
1869 iscsi_session_attr(targetalias, ISCSI_PARAM_TARGET_ALIAS, 0);
1870
1871 static ssize_t
1872 show_priv_session_state(struct device *dev, struct device_attribute *attr,
1873                         char *buf)
1874 {
1875         struct iscsi_cls_session *session = iscsi_dev_to_session(dev->parent);
1876         return sprintf(buf, "%s\n", iscsi_session_state_name(session->state));
1877 }
1878 static ISCSI_CLASS_ATTR(priv_sess, state, S_IRUGO, show_priv_session_state,
1879                         NULL);
1880
1881 #define iscsi_priv_session_attr_show(field, format)                     \
1882 static ssize_t                                                          \
1883 show_priv_session_##field(struct device *dev,                           \
1884                           struct device_attribute *attr, char *buf)     \
1885 {                                                                       \
1886         struct iscsi_cls_session *session =                             \
1887                         iscsi_dev_to_session(dev->parent);              \
1888         if (session->field == -1)                                       \
1889                 return sprintf(buf, "off\n");                           \
1890         return sprintf(buf, format"\n", session->field);                \
1891 }
1892
1893 #define iscsi_priv_session_attr_store(field)                            \
1894 static ssize_t                                                          \
1895 store_priv_session_##field(struct device *dev,                          \
1896                            struct device_attribute *attr,               \
1897                            const char *buf, size_t count)               \
1898 {                                                                       \
1899         int val;                                                        \
1900         char *cp;                                                       \
1901         struct iscsi_cls_session *session =                             \
1902                 iscsi_dev_to_session(dev->parent);                      \
1903         if ((session->state == ISCSI_SESSION_FREE) ||                   \
1904             (session->state == ISCSI_SESSION_FAILED))                   \
1905                 return -EBUSY;                                          \
1906         if (strncmp(buf, "off", 3) == 0)                                \
1907                 session->field = -1;                                    \
1908         else {                                                          \
1909                 val = simple_strtoul(buf, &cp, 0);                      \
1910                 if (*cp != '\0' && *cp != '\n')                         \
1911                         return -EINVAL;                                 \
1912                 session->field = val;                                   \
1913         }                                                               \
1914         return count;                                                   \
1915 }
1916
1917 #define iscsi_priv_session_rw_attr(field, format)                       \
1918         iscsi_priv_session_attr_show(field, format)                     \
1919         iscsi_priv_session_attr_store(field)                            \
1920 static ISCSI_CLASS_ATTR(priv_sess, field, S_IRUGO | S_IWUGO,            \
1921                         show_priv_session_##field,                      \
1922                         store_priv_session_##field)
1923 iscsi_priv_session_rw_attr(recovery_tmo, "%d");
1924
1925 /*
1926  * iSCSI host attrs
1927  */
1928 #define iscsi_host_attr_show(param)                                     \
1929 static ssize_t                                                          \
1930 show_host_param_##param(struct device *dev,                             \
1931                         struct device_attribute *attr, char *buf)       \
1932 {                                                                       \
1933         struct Scsi_Host *shost = transport_class_to_shost(dev);        \
1934         struct iscsi_internal *priv = to_iscsi_internal(shost->transportt); \
1935         return priv->iscsi_transport->get_host_param(shost, param, buf); \
1936 }
1937
1938 #define iscsi_host_attr(field, param)                                   \
1939         iscsi_host_attr_show(param)                                     \
1940 static ISCSI_CLASS_ATTR(host, field, S_IRUGO, show_host_param_##param,  \
1941                         NULL);
1942
1943 iscsi_host_attr(netdev, ISCSI_HOST_PARAM_NETDEV_NAME);
1944 iscsi_host_attr(hwaddress, ISCSI_HOST_PARAM_HWADDRESS);
1945 iscsi_host_attr(ipaddress, ISCSI_HOST_PARAM_IPADDRESS);
1946 iscsi_host_attr(initiatorname, ISCSI_HOST_PARAM_INITIATOR_NAME);
1947
1948 #define SETUP_PRIV_SESSION_RD_ATTR(field)                               \
1949 do {                                                                    \
1950         priv->session_attrs[count] = &dev_attr_priv_sess_##field; \
1951         count++;                                                        \
1952 } while (0)
1953
1954 #define SETUP_PRIV_SESSION_RW_ATTR(field)                               \
1955 do {                                                                    \
1956         priv->session_attrs[count] = &dev_attr_priv_sess_##field;       \
1957         count++;                                                        \
1958 } while (0)
1959
1960 #define SETUP_SESSION_RD_ATTR(field, param_flag)                        \
1961 do {                                                                    \
1962         if (tt->param_mask & param_flag) {                              \
1963                 priv->session_attrs[count] = &dev_attr_sess_##field; \
1964                 count++;                                                \
1965         }                                                               \
1966 } while (0)
1967
1968 #define SETUP_CONN_RD_ATTR(field, param_flag)                           \
1969 do {                                                                    \
1970         if (tt->param_mask & param_flag) {                              \
1971                 priv->conn_attrs[count] = &dev_attr_conn_##field; \
1972                 count++;                                                \
1973         }                                                               \
1974 } while (0)
1975
1976 #define SETUP_HOST_RD_ATTR(field, param_flag)                           \
1977 do {                                                                    \
1978         if (tt->host_param_mask & param_flag) {                         \
1979                 priv->host_attrs[count] = &dev_attr_host_##field; \
1980                 count++;                                                \
1981         }                                                               \
1982 } while (0)
1983
1984 static int iscsi_session_match(struct attribute_container *cont,
1985                            struct device *dev)
1986 {
1987         struct iscsi_cls_session *session;
1988         struct Scsi_Host *shost;
1989         struct iscsi_internal *priv;
1990
1991         if (!iscsi_is_session_dev(dev))
1992                 return 0;
1993
1994         session = iscsi_dev_to_session(dev);
1995         shost = iscsi_session_to_shost(session);
1996         if (!shost->transportt)
1997                 return 0;
1998
1999         priv = to_iscsi_internal(shost->transportt);
2000         if (priv->session_cont.ac.class != &iscsi_session_class.class)
2001                 return 0;
2002
2003         return &priv->session_cont.ac == cont;
2004 }
2005
2006 static int iscsi_conn_match(struct attribute_container *cont,
2007                            struct device *dev)
2008 {
2009         struct iscsi_cls_session *session;
2010         struct iscsi_cls_conn *conn;
2011         struct Scsi_Host *shost;
2012         struct iscsi_internal *priv;
2013
2014         if (!iscsi_is_conn_dev(dev))
2015                 return 0;
2016
2017         conn = iscsi_dev_to_conn(dev);
2018         session = iscsi_dev_to_session(conn->dev.parent);
2019         shost = iscsi_session_to_shost(session);
2020
2021         if (!shost->transportt)
2022                 return 0;
2023
2024         priv = to_iscsi_internal(shost->transportt);
2025         if (priv->conn_cont.ac.class != &iscsi_connection_class.class)
2026                 return 0;
2027
2028         return &priv->conn_cont.ac == cont;
2029 }
2030
2031 static int iscsi_host_match(struct attribute_container *cont,
2032                             struct device *dev)
2033 {
2034         struct Scsi_Host *shost;
2035         struct iscsi_internal *priv;
2036
2037         if (!scsi_is_host_device(dev))
2038                 return 0;
2039
2040         shost = dev_to_shost(dev);
2041         if (!shost->transportt  ||
2042             shost->transportt->host_attrs.ac.class != &iscsi_host_class.class)
2043                 return 0;
2044
2045         priv = to_iscsi_internal(shost->transportt);
2046         return &priv->t.host_attrs.ac == cont;
2047 }
2048
2049 struct scsi_transport_template *
2050 iscsi_register_transport(struct iscsi_transport *tt)
2051 {
2052         struct iscsi_internal *priv;
2053         unsigned long flags;
2054         int count = 0, err;
2055
2056         BUG_ON(!tt);
2057
2058         priv = iscsi_if_transport_lookup(tt);
2059         if (priv)
2060                 return NULL;
2061
2062         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
2063         if (!priv)
2064                 return NULL;
2065         INIT_LIST_HEAD(&priv->list);
2066         priv->iscsi_transport = tt;
2067         priv->t.user_scan = iscsi_user_scan;
2068         priv->t.create_work_queue = 1;
2069
2070         priv->dev.class = &iscsi_transport_class;
2071         dev_set_name(&priv->dev, "%s", tt->name);
2072         err = device_register(&priv->dev);
2073         if (err)
2074                 goto free_priv;
2075
2076         err = sysfs_create_group(&priv->dev.kobj, &iscsi_transport_group);
2077         if (err)
2078                 goto unregister_dev;
2079
2080         /* host parameters */
2081         priv->t.host_attrs.ac.attrs = &priv->host_attrs[0];
2082         priv->t.host_attrs.ac.class = &iscsi_host_class.class;
2083         priv->t.host_attrs.ac.match = iscsi_host_match;
2084         priv->t.host_size = sizeof(struct iscsi_cls_host);
2085         transport_container_register(&priv->t.host_attrs);
2086
2087         SETUP_HOST_RD_ATTR(netdev, ISCSI_HOST_NETDEV_NAME);
2088         SETUP_HOST_RD_ATTR(ipaddress, ISCSI_HOST_IPADDRESS);
2089         SETUP_HOST_RD_ATTR(hwaddress, ISCSI_HOST_HWADDRESS);
2090         SETUP_HOST_RD_ATTR(initiatorname, ISCSI_HOST_INITIATOR_NAME);
2091         BUG_ON(count > ISCSI_HOST_ATTRS);
2092         priv->host_attrs[count] = NULL;
2093         count = 0;
2094
2095         /* connection parameters */
2096         priv->conn_cont.ac.attrs = &priv->conn_attrs[0];
2097         priv->conn_cont.ac.class = &iscsi_connection_class.class;
2098         priv->conn_cont.ac.match = iscsi_conn_match;
2099         transport_container_register(&priv->conn_cont);
2100
2101         SETUP_CONN_RD_ATTR(max_recv_dlength, ISCSI_MAX_RECV_DLENGTH);
2102         SETUP_CONN_RD_ATTR(max_xmit_dlength, ISCSI_MAX_XMIT_DLENGTH);
2103         SETUP_CONN_RD_ATTR(header_digest, ISCSI_HDRDGST_EN);
2104         SETUP_CONN_RD_ATTR(data_digest, ISCSI_DATADGST_EN);
2105         SETUP_CONN_RD_ATTR(ifmarker, ISCSI_IFMARKER_EN);
2106         SETUP_CONN_RD_ATTR(ofmarker, ISCSI_OFMARKER_EN);
2107         SETUP_CONN_RD_ATTR(address, ISCSI_CONN_ADDRESS);
2108         SETUP_CONN_RD_ATTR(port, ISCSI_CONN_PORT);
2109         SETUP_CONN_RD_ATTR(exp_statsn, ISCSI_EXP_STATSN);
2110         SETUP_CONN_RD_ATTR(persistent_address, ISCSI_PERSISTENT_ADDRESS);
2111         SETUP_CONN_RD_ATTR(persistent_port, ISCSI_PERSISTENT_PORT);
2112         SETUP_CONN_RD_ATTR(ping_tmo, ISCSI_PING_TMO);
2113         SETUP_CONN_RD_ATTR(recv_tmo, ISCSI_RECV_TMO);
2114
2115         BUG_ON(count > ISCSI_CONN_ATTRS);
2116         priv->conn_attrs[count] = NULL;
2117         count = 0;
2118
2119         /* session parameters */
2120         priv->session_cont.ac.attrs = &priv->session_attrs[0];
2121         priv->session_cont.ac.class = &iscsi_session_class.class;
2122         priv->session_cont.ac.match = iscsi_session_match;
2123         transport_container_register(&priv->session_cont);
2124
2125         SETUP_SESSION_RD_ATTR(initial_r2t, ISCSI_INITIAL_R2T_EN);
2126         SETUP_SESSION_RD_ATTR(max_outstanding_r2t, ISCSI_MAX_R2T);
2127         SETUP_SESSION_RD_ATTR(immediate_data, ISCSI_IMM_DATA_EN);
2128         SETUP_SESSION_RD_ATTR(first_burst_len, ISCSI_FIRST_BURST);
2129         SETUP_SESSION_RD_ATTR(max_burst_len, ISCSI_MAX_BURST);
2130         SETUP_SESSION_RD_ATTR(data_pdu_in_order, ISCSI_PDU_INORDER_EN);
2131         SETUP_SESSION_RD_ATTR(data_seq_in_order, ISCSI_DATASEQ_INORDER_EN);
2132         SETUP_SESSION_RD_ATTR(erl, ISCSI_ERL);
2133         SETUP_SESSION_RD_ATTR(targetname, ISCSI_TARGET_NAME);
2134         SETUP_SESSION_RD_ATTR(tpgt, ISCSI_TPGT);
2135         SETUP_SESSION_RD_ATTR(password, ISCSI_USERNAME);
2136         SETUP_SESSION_RD_ATTR(password_in, ISCSI_USERNAME_IN);
2137         SETUP_SESSION_RD_ATTR(username, ISCSI_PASSWORD);
2138         SETUP_SESSION_RD_ATTR(username_in, ISCSI_PASSWORD_IN);
2139         SETUP_SESSION_RD_ATTR(fast_abort, ISCSI_FAST_ABORT);
2140         SETUP_SESSION_RD_ATTR(abort_tmo, ISCSI_ABORT_TMO);
2141         SETUP_SESSION_RD_ATTR(lu_reset_tmo,ISCSI_LU_RESET_TMO);
2142         SETUP_SESSION_RD_ATTR(tgt_reset_tmo,ISCSI_TGT_RESET_TMO);
2143         SETUP_SESSION_RD_ATTR(ifacename, ISCSI_IFACE_NAME);
2144         SETUP_SESSION_RD_ATTR(initiatorname, ISCSI_INITIATOR_NAME);
2145         SETUP_SESSION_RD_ATTR(targetalias, ISCSI_TARGET_ALIAS);
2146         SETUP_PRIV_SESSION_RW_ATTR(recovery_tmo);
2147         SETUP_PRIV_SESSION_RD_ATTR(state);
2148
2149         BUG_ON(count > ISCSI_SESSION_ATTRS);
2150         priv->session_attrs[count] = NULL;
2151
2152         spin_lock_irqsave(&iscsi_transport_lock, flags);
2153         list_add(&priv->list, &iscsi_transports);
2154         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
2155
2156         printk(KERN_NOTICE "iscsi: registered transport (%s)\n", tt->name);
2157         return &priv->t;
2158
2159 unregister_dev:
2160         device_unregister(&priv->dev);
2161         return NULL;
2162 free_priv:
2163         kfree(priv);
2164         return NULL;
2165 }
2166 EXPORT_SYMBOL_GPL(iscsi_register_transport);
2167
2168 int iscsi_unregister_transport(struct iscsi_transport *tt)
2169 {
2170         struct iscsi_internal *priv;
2171         unsigned long flags;
2172
2173         BUG_ON(!tt);
2174
2175         mutex_lock(&rx_queue_mutex);
2176
2177         priv = iscsi_if_transport_lookup(tt);
2178         BUG_ON (!priv);
2179
2180         spin_lock_irqsave(&iscsi_transport_lock, flags);
2181         list_del(&priv->list);
2182         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
2183
2184         transport_container_unregister(&priv->conn_cont);
2185         transport_container_unregister(&priv->session_cont);
2186         transport_container_unregister(&priv->t.host_attrs);
2187
2188         sysfs_remove_group(&priv->dev.kobj, &iscsi_transport_group);
2189         device_unregister(&priv->dev);
2190         mutex_unlock(&rx_queue_mutex);
2191
2192         return 0;
2193 }
2194 EXPORT_SYMBOL_GPL(iscsi_unregister_transport);
2195
2196 static __init int iscsi_transport_init(void)
2197 {
2198         int err;
2199
2200         printk(KERN_INFO "Loading iSCSI transport class v%s.\n",
2201                 ISCSI_TRANSPORT_VERSION);
2202
2203         atomic_set(&iscsi_session_nr, 0);
2204
2205         err = class_register(&iscsi_transport_class);
2206         if (err)
2207                 return err;
2208
2209         err = class_register(&iscsi_endpoint_class);
2210         if (err)
2211                 goto unregister_transport_class;
2212
2213         err = transport_class_register(&iscsi_host_class);
2214         if (err)
2215                 goto unregister_endpoint_class;
2216
2217         err = transport_class_register(&iscsi_connection_class);
2218         if (err)
2219                 goto unregister_host_class;
2220
2221         err = transport_class_register(&iscsi_session_class);
2222         if (err)
2223                 goto unregister_conn_class;
2224
2225         nls = netlink_kernel_create(&init_net, NETLINK_ISCSI, 1, iscsi_if_rx,
2226                                     NULL, THIS_MODULE);
2227         if (!nls) {
2228                 err = -ENOBUFS;
2229                 goto unregister_session_class;
2230         }
2231
2232         iscsi_eh_timer_workq = create_singlethread_workqueue("iscsi_eh");
2233         if (!iscsi_eh_timer_workq)
2234                 goto release_nls;
2235
2236         return 0;
2237
2238 release_nls:
2239         netlink_kernel_release(nls);
2240 unregister_session_class:
2241         transport_class_unregister(&iscsi_session_class);
2242 unregister_conn_class:
2243         transport_class_unregister(&iscsi_connection_class);
2244 unregister_host_class:
2245         transport_class_unregister(&iscsi_host_class);
2246 unregister_endpoint_class:
2247         class_unregister(&iscsi_endpoint_class);
2248 unregister_transport_class:
2249         class_unregister(&iscsi_transport_class);
2250         return err;
2251 }
2252
2253 static void __exit iscsi_transport_exit(void)
2254 {
2255         destroy_workqueue(iscsi_eh_timer_workq);
2256         netlink_kernel_release(nls);
2257         transport_class_unregister(&iscsi_connection_class);
2258         transport_class_unregister(&iscsi_session_class);
2259         transport_class_unregister(&iscsi_host_class);
2260         class_unregister(&iscsi_endpoint_class);
2261         class_unregister(&iscsi_transport_class);
2262 }
2263
2264 module_init(iscsi_transport_init);
2265 module_exit(iscsi_transport_exit);
2266
2267 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
2268               "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
2269               "Alex Aizman <itn780@yahoo.com>");
2270 MODULE_DESCRIPTION("iSCSI Transport Interface");
2271 MODULE_LICENSE("GPL");
2272 MODULE_VERSION(ISCSI_TRANSPORT_VERSION);
2273 MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_ISCSI);