linux/drivers/scsi/scsi_transport_iscsi.c
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   1/*
   2 * iSCSI transport class definitions
   3 *
   4 * Copyright (C) IBM Corporation, 2004
   5 * Copyright (C) Mike Christie, 2004 - 2005
   6 * Copyright (C) Dmitry Yusupov, 2004 - 2005
   7 * Copyright (C) Alex Aizman, 2004 - 2005
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License as published by
  11 * the Free Software Foundation; either version 2 of the License, or
  12 * (at your option) any later version.
  13 *
  14 * This program is distributed in the hope that it will be useful,
  15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 * GNU General Public License for more details.
  18 *
  19 * You should have received a copy of the GNU General Public License
  20 * along with this program; if not, write to the Free Software
  21 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  22 */
  23#include <linux/module.h>
  24#include <linux/mutex.h>
  25#include <net/tcp.h>
  26#include <scsi/scsi.h>
  27#include <scsi/scsi_host.h>
  28#include <scsi/scsi_device.h>
  29#include <scsi/scsi_transport.h>
  30#include <scsi/scsi_transport_iscsi.h>
  31#include <scsi/iscsi_if.h>
  32
  33#define ISCSI_SESSION_ATTRS 21
  34#define ISCSI_CONN_ATTRS 13
  35#define ISCSI_HOST_ATTRS 4
  36
  37#define ISCSI_TRANSPORT_VERSION "2.0-870"
  38
  39static int dbg_session;
  40module_param_named(debug_session, dbg_session, int,
  41                   S_IRUGO | S_IWUSR);
  42MODULE_PARM_DESC(debug_session,
  43                 "Turn on debugging for sessions in scsi_transport_iscsi "
  44                 "module. Set to 1 to turn on, and zero to turn off. Default "
  45                 "is off.");
  46
  47static int dbg_conn;
  48module_param_named(debug_conn, dbg_conn, int,
  49                   S_IRUGO | S_IWUSR);
  50MODULE_PARM_DESC(debug_conn,
  51                 "Turn on debugging for connections in scsi_transport_iscsi "
  52                 "module. Set to 1 to turn on, and zero to turn off. Default "
  53                 "is off.");
  54
  55#define ISCSI_DBG_TRANS_SESSION(_session, dbg_fmt, arg...)              \
  56        do {                                                            \
  57                if (dbg_session)                                        \
  58                        iscsi_cls_session_printk(KERN_INFO, _session,   \
  59                                                 "%s: " dbg_fmt,        \
  60                                                 __func__, ##arg);      \
  61        } while (0);
  62
  63#define ISCSI_DBG_TRANS_CONN(_conn, dbg_fmt, arg...)                    \
  64        do {                                                            \
  65                if (dbg_conn)                                           \
  66                        iscsi_cls_conn_printk(KERN_INFO, _conn,         \
  67                                              "%s: " dbg_fmt,           \
  68                                              __func__, ##arg); \
  69        } while (0);
  70
  71struct iscsi_internal {
  72        struct scsi_transport_template t;
  73        struct iscsi_transport *iscsi_transport;
  74        struct list_head list;
  75        struct device dev;
  76
  77        struct device_attribute *host_attrs[ISCSI_HOST_ATTRS + 1];
  78        struct transport_container conn_cont;
  79        struct device_attribute *conn_attrs[ISCSI_CONN_ATTRS + 1];
  80        struct transport_container session_cont;
  81        struct device_attribute *session_attrs[ISCSI_SESSION_ATTRS + 1];
  82};
  83
  84static atomic_t iscsi_session_nr; /* sysfs session id for next new session */
  85static struct workqueue_struct *iscsi_eh_timer_workq;
  86
  87/*
  88 * list of registered transports and lock that must
  89 * be held while accessing list. The iscsi_transport_lock must
  90 * be acquired after the rx_queue_mutex.
  91 */
  92static LIST_HEAD(iscsi_transports);
  93static DEFINE_SPINLOCK(iscsi_transport_lock);
  94
  95#define to_iscsi_internal(tmpl) \
  96        container_of(tmpl, struct iscsi_internal, t)
  97
  98#define dev_to_iscsi_internal(_dev) \
  99        container_of(_dev, struct iscsi_internal, dev)
 100
 101static void iscsi_transport_release(struct device *dev)
 102{
 103        struct iscsi_internal *priv = dev_to_iscsi_internal(dev);
 104        kfree(priv);
 105}
 106
 107/*
 108 * iscsi_transport_class represents the iscsi_transports that are
 109 * registered.
 110 */
 111static struct class iscsi_transport_class = {
 112        .name = "iscsi_transport",
 113        .dev_release = iscsi_transport_release,
 114};
 115
 116static ssize_t
 117show_transport_handle(struct device *dev, struct device_attribute *attr,
 118                      char *buf)
 119{
 120        struct iscsi_internal *priv = dev_to_iscsi_internal(dev);
 121        return sprintf(buf, "%llu\n", (unsigned long long)iscsi_handle(priv->iscsi_transport));
 122}
 123static DEVICE_ATTR(handle, S_IRUGO, show_transport_handle, NULL);
 124
 125#define show_transport_attr(name, format)                               \
 126static ssize_t                                                          \
 127show_transport_##name(struct device *dev,                               \
 128                      struct device_attribute *attr,char *buf)          \
 129{                                                                       \
 130        struct iscsi_internal *priv = dev_to_iscsi_internal(dev);       \
 131        return sprintf(buf, format"\n", priv->iscsi_transport->name);   \
 132}                                                                       \
 133static DEVICE_ATTR(name, S_IRUGO, show_transport_##name, NULL);
 134
 135show_transport_attr(caps, "0x%x");
 136
 137static struct attribute *iscsi_transport_attrs[] = {
 138        &dev_attr_handle.attr,
 139        &dev_attr_caps.attr,
 140        NULL,
 141};
 142
 143static struct attribute_group iscsi_transport_group = {
 144        .attrs = iscsi_transport_attrs,
 145};
 146
 147/*
 148 * iSCSI endpoint attrs
 149 */
 150#define iscsi_dev_to_endpoint(_dev) \
 151        container_of(_dev, struct iscsi_endpoint, dev)
 152
 153#define ISCSI_ATTR(_prefix,_name,_mode,_show,_store)    \
 154struct device_attribute dev_attr_##_prefix##_##_name =  \
 155        __ATTR(_name,_mode,_show,_store)
 156
 157static void iscsi_endpoint_release(struct device *dev)
 158{
 159        struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
 160        kfree(ep);
 161}
 162
 163static struct class iscsi_endpoint_class = {
 164        .name = "iscsi_endpoint",
 165        .dev_release = iscsi_endpoint_release,
 166};
 167
 168static ssize_t
 169show_ep_handle(struct device *dev, struct device_attribute *attr, char *buf)
 170{
 171        struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
 172        return sprintf(buf, "%llu\n", (unsigned long long) ep->id);
 173}
 174static ISCSI_ATTR(ep, handle, S_IRUGO, show_ep_handle, NULL);
 175
 176static struct attribute *iscsi_endpoint_attrs[] = {
 177        &dev_attr_ep_handle.attr,
 178        NULL,
 179};
 180
 181static struct attribute_group iscsi_endpoint_group = {
 182        .attrs = iscsi_endpoint_attrs,
 183};
 184
 185#define ISCSI_MAX_EPID -1
 186
 187static int iscsi_match_epid(struct device *dev, void *data)
 188{
 189        struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
 190        uint64_t *epid = (uint64_t *) data;
 191
 192        return *epid == ep->id;
 193}
 194
 195struct iscsi_endpoint *
 196iscsi_create_endpoint(int dd_size)
 197{
 198        struct device *dev;
 199        struct iscsi_endpoint *ep;
 200        uint64_t id;
 201        int err;
 202
 203        for (id = 1; id < ISCSI_MAX_EPID; id++) {
 204                dev = class_find_device(&iscsi_endpoint_class, NULL, &id,
 205                                        iscsi_match_epid);
 206                if (!dev)
 207                        break;
 208        }
 209        if (id == ISCSI_MAX_EPID) {
 210                printk(KERN_ERR "Too many connections. Max supported %u\n",
 211                       ISCSI_MAX_EPID - 1);
 212                return NULL;
 213        }
 214
 215        ep = kzalloc(sizeof(*ep) + dd_size, GFP_KERNEL);
 216        if (!ep)
 217                return NULL;
 218
 219        ep->id = id;
 220        ep->dev.class = &iscsi_endpoint_class;
 221        dev_set_name(&ep->dev, "ep-%llu", (unsigned long long) id);
 222        err = device_register(&ep->dev);
 223        if (err)
 224                goto free_ep;
 225
 226        err = sysfs_create_group(&ep->dev.kobj, &iscsi_endpoint_group);
 227        if (err)
 228                goto unregister_dev;
 229
 230        if (dd_size)
 231                ep->dd_data = &ep[1];
 232        return ep;
 233
 234unregister_dev:
 235        device_unregister(&ep->dev);
 236        return NULL;
 237
 238free_ep:
 239        kfree(ep);
 240        return NULL;
 241}
 242EXPORT_SYMBOL_GPL(iscsi_create_endpoint);
 243
 244void iscsi_destroy_endpoint(struct iscsi_endpoint *ep)
 245{
 246        sysfs_remove_group(&ep->dev.kobj, &iscsi_endpoint_group);
 247        device_unregister(&ep->dev);
 248}
 249EXPORT_SYMBOL_GPL(iscsi_destroy_endpoint);
 250
 251struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle)
 252{
 253        struct iscsi_endpoint *ep;
 254        struct device *dev;
 255
 256        dev = class_find_device(&iscsi_endpoint_class, NULL, &handle,
 257                                iscsi_match_epid);
 258        if (!dev)
 259                return NULL;
 260
 261        ep = iscsi_dev_to_endpoint(dev);
 262        /*
 263         * we can drop this now because the interface will prevent
 264         * removals and lookups from racing.
 265         */
 266        put_device(dev);
 267        return ep;
 268}
 269EXPORT_SYMBOL_GPL(iscsi_lookup_endpoint);
 270
 271static int iscsi_setup_host(struct transport_container *tc, struct device *dev,
 272                            struct device *cdev)
 273{
 274        struct Scsi_Host *shost = dev_to_shost(dev);
 275        struct iscsi_cls_host *ihost = shost->shost_data;
 276
 277        memset(ihost, 0, sizeof(*ihost));
 278        atomic_set(&ihost->nr_scans, 0);
 279        mutex_init(&ihost->mutex);
 280        return 0;
 281}
 282
 283static DECLARE_TRANSPORT_CLASS(iscsi_host_class,
 284                               "iscsi_host",
 285                               iscsi_setup_host,
 286                               NULL,
 287                               NULL);
 288
 289static DECLARE_TRANSPORT_CLASS(iscsi_session_class,
 290                               "iscsi_session",
 291                               NULL,
 292                               NULL,
 293                               NULL);
 294
 295static DECLARE_TRANSPORT_CLASS(iscsi_connection_class,
 296                               "iscsi_connection",
 297                               NULL,
 298                               NULL,
 299                               NULL);
 300
 301static struct sock *nls;
 302static DEFINE_MUTEX(rx_queue_mutex);
 303
 304static LIST_HEAD(sesslist);
 305static DEFINE_SPINLOCK(sesslock);
 306static LIST_HEAD(connlist);
 307static DEFINE_SPINLOCK(connlock);
 308
 309static uint32_t iscsi_conn_get_sid(struct iscsi_cls_conn *conn)
 310{
 311        struct iscsi_cls_session *sess = iscsi_dev_to_session(conn->dev.parent);
 312        return sess->sid;
 313}
 314
 315/*
 316 * Returns the matching session to a given sid
 317 */
 318static struct iscsi_cls_session *iscsi_session_lookup(uint32_t sid)
 319{
 320        unsigned long flags;
 321        struct iscsi_cls_session *sess;
 322
 323        spin_lock_irqsave(&sesslock, flags);
 324        list_for_each_entry(sess, &sesslist, sess_list) {
 325                if (sess->sid == sid) {
 326                        spin_unlock_irqrestore(&sesslock, flags);
 327                        return sess;
 328                }
 329        }
 330        spin_unlock_irqrestore(&sesslock, flags);
 331        return NULL;
 332}
 333
 334/*
 335 * Returns the matching connection to a given sid / cid tuple
 336 */
 337static struct iscsi_cls_conn *iscsi_conn_lookup(uint32_t sid, uint32_t cid)
 338{
 339        unsigned long flags;
 340        struct iscsi_cls_conn *conn;
 341
 342        spin_lock_irqsave(&connlock, flags);
 343        list_for_each_entry(conn, &connlist, conn_list) {
 344                if ((conn->cid == cid) && (iscsi_conn_get_sid(conn) == sid)) {
 345                        spin_unlock_irqrestore(&connlock, flags);
 346                        return conn;
 347                }
 348        }
 349        spin_unlock_irqrestore(&connlock, flags);
 350        return NULL;
 351}
 352
 353/*
 354 * The following functions can be used by LLDs that allocate
 355 * their own scsi_hosts or by software iscsi LLDs
 356 */
 357static struct {
 358        int value;
 359        char *name;
 360} iscsi_session_state_names[] = {
 361        { ISCSI_SESSION_LOGGED_IN,      "LOGGED_IN" },
 362        { ISCSI_SESSION_FAILED,         "FAILED" },
 363        { ISCSI_SESSION_FREE,           "FREE" },
 364};
 365
 366static const char *iscsi_session_state_name(int state)
 367{
 368        int i;
 369        char *name = NULL;
 370
 371        for (i = 0; i < ARRAY_SIZE(iscsi_session_state_names); i++) {
 372                if (iscsi_session_state_names[i].value == state) {
 373                        name = iscsi_session_state_names[i].name;
 374                        break;
 375                }
 376        }
 377        return name;
 378}
 379
 380int iscsi_session_chkready(struct iscsi_cls_session *session)
 381{
 382        unsigned long flags;
 383        int err;
 384
 385        spin_lock_irqsave(&session->lock, flags);
 386        switch (session->state) {
 387        case ISCSI_SESSION_LOGGED_IN:
 388                err = 0;
 389                break;
 390        case ISCSI_SESSION_FAILED:
 391                err = DID_IMM_RETRY << 16;
 392                break;
 393        case ISCSI_SESSION_FREE:
 394                err = DID_TRANSPORT_FAILFAST << 16;
 395                break;
 396        default:
 397                err = DID_NO_CONNECT << 16;
 398                break;
 399        }
 400        spin_unlock_irqrestore(&session->lock, flags);
 401        return err;
 402}
 403EXPORT_SYMBOL_GPL(iscsi_session_chkready);
 404
 405static void iscsi_session_release(struct device *dev)
 406{
 407        struct iscsi_cls_session *session = iscsi_dev_to_session(dev);
 408        struct Scsi_Host *shost;
 409
 410        shost = iscsi_session_to_shost(session);
 411        scsi_host_put(shost);
 412        ISCSI_DBG_TRANS_SESSION(session, "Completing session release\n");
 413        kfree(session);
 414}
 415
 416static int iscsi_is_session_dev(const struct device *dev)
 417{
 418        return dev->release == iscsi_session_release;
 419}
 420
 421static int iscsi_iter_session_fn(struct device *dev, void *data)
 422{
 423        void (* fn) (struct iscsi_cls_session *) = data;
 424
 425        if (!iscsi_is_session_dev(dev))
 426                return 0;
 427        fn(iscsi_dev_to_session(dev));
 428        return 0;
 429}
 430
 431void iscsi_host_for_each_session(struct Scsi_Host *shost,
 432                                 void (*fn)(struct iscsi_cls_session *))
 433{
 434        device_for_each_child(&shost->shost_gendev, fn,
 435                              iscsi_iter_session_fn);
 436}
 437EXPORT_SYMBOL_GPL(iscsi_host_for_each_session);
 438
 439/**
 440 * iscsi_scan_finished - helper to report when running scans are done
 441 * @shost: scsi host
 442 * @time: scan run time
 443 *
 444 * This function can be used by drives like qla4xxx to report to the scsi
 445 * layer when the scans it kicked off at module load time are done.
 446 */
 447int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time)
 448{
 449        struct iscsi_cls_host *ihost = shost->shost_data;
 450        /*
 451         * qla4xxx will have kicked off some session unblocks before calling
 452         * scsi_scan_host, so just wait for them to complete.
 453         */
 454        return !atomic_read(&ihost->nr_scans);
 455}
 456EXPORT_SYMBOL_GPL(iscsi_scan_finished);
 457
 458struct iscsi_scan_data {
 459        unsigned int channel;
 460        unsigned int id;
 461        unsigned int lun;
 462};
 463
 464static int iscsi_user_scan_session(struct device *dev, void *data)
 465{
 466        struct iscsi_scan_data *scan_data = data;
 467        struct iscsi_cls_session *session;
 468        struct Scsi_Host *shost;
 469        struct iscsi_cls_host *ihost;
 470        unsigned long flags;
 471        unsigned int id;
 472
 473        if (!iscsi_is_session_dev(dev))
 474                return 0;
 475
 476        session = iscsi_dev_to_session(dev);
 477
 478        ISCSI_DBG_TRANS_SESSION(session, "Scanning session\n");
 479
 480        shost = iscsi_session_to_shost(session);
 481        ihost = shost->shost_data;
 482
 483        mutex_lock(&ihost->mutex);
 484        spin_lock_irqsave(&session->lock, flags);
 485        if (session->state != ISCSI_SESSION_LOGGED_IN) {
 486                spin_unlock_irqrestore(&session->lock, flags);
 487                goto user_scan_exit;
 488        }
 489        id = session->target_id;
 490        spin_unlock_irqrestore(&session->lock, flags);
 491
 492        if (id != ISCSI_MAX_TARGET) {
 493                if ((scan_data->channel == SCAN_WILD_CARD ||
 494                     scan_data->channel == 0) &&
 495                    (scan_data->id == SCAN_WILD_CARD ||
 496                     scan_data->id == id))
 497                        scsi_scan_target(&session->dev, 0, id,
 498                                         scan_data->lun, 1);
 499        }
 500
 501user_scan_exit:
 502        mutex_unlock(&ihost->mutex);
 503        ISCSI_DBG_TRANS_SESSION(session, "Completed session scan\n");
 504        return 0;
 505}
 506
 507static int iscsi_user_scan(struct Scsi_Host *shost, uint channel,
 508                           uint id, uint lun)
 509{
 510        struct iscsi_scan_data scan_data;
 511
 512        scan_data.channel = channel;
 513        scan_data.id = id;
 514        scan_data.lun = lun;
 515
 516        return device_for_each_child(&shost->shost_gendev, &scan_data,
 517                                     iscsi_user_scan_session);
 518}
 519
 520static void iscsi_scan_session(struct work_struct *work)
 521{
 522        struct iscsi_cls_session *session =
 523                        container_of(work, struct iscsi_cls_session, scan_work);
 524        struct Scsi_Host *shost = iscsi_session_to_shost(session);
 525        struct iscsi_cls_host *ihost = shost->shost_data;
 526        struct iscsi_scan_data scan_data;
 527
 528        scan_data.channel = 0;
 529        scan_data.id = SCAN_WILD_CARD;
 530        scan_data.lun = SCAN_WILD_CARD;
 531
 532        iscsi_user_scan_session(&session->dev, &scan_data);
 533        atomic_dec(&ihost->nr_scans);
 534}
 535
 536static void session_recovery_timedout(struct work_struct *work)
 537{
 538        struct iscsi_cls_session *session =
 539                container_of(work, struct iscsi_cls_session,
 540                             recovery_work.work);
 541        unsigned long flags;
 542
 543        iscsi_cls_session_printk(KERN_INFO, session,
 544                                 "session recovery timed out after %d secs\n",
 545                                 session->recovery_tmo);
 546
 547        spin_lock_irqsave(&session->lock, flags);
 548        switch (session->state) {
 549        case ISCSI_SESSION_FAILED:
 550                session->state = ISCSI_SESSION_FREE;
 551                break;
 552        case ISCSI_SESSION_LOGGED_IN:
 553        case ISCSI_SESSION_FREE:
 554                /* we raced with the unblock's flush */
 555                spin_unlock_irqrestore(&session->lock, flags);
 556                return;
 557        }
 558        spin_unlock_irqrestore(&session->lock, flags);
 559
 560        if (session->transport->session_recovery_timedout)
 561                session->transport->session_recovery_timedout(session);
 562
 563        ISCSI_DBG_TRANS_SESSION(session, "Unblocking SCSI target\n");
 564        scsi_target_unblock(&session->dev);
 565        ISCSI_DBG_TRANS_SESSION(session, "Completed unblocking SCSI target\n");
 566}
 567
 568static void __iscsi_unblock_session(struct work_struct *work)
 569{
 570        struct iscsi_cls_session *session =
 571                        container_of(work, struct iscsi_cls_session,
 572                                     unblock_work);
 573        struct Scsi_Host *shost = iscsi_session_to_shost(session);
 574        struct iscsi_cls_host *ihost = shost->shost_data;
 575        unsigned long flags;
 576
 577        ISCSI_DBG_TRANS_SESSION(session, "Unblocking session\n");
 578        /*
 579         * The recovery and unblock work get run from the same workqueue,
 580         * so try to cancel it if it was going to run after this unblock.
 581         */
 582        cancel_delayed_work(&session->recovery_work);
 583        spin_lock_irqsave(&session->lock, flags);
 584        session->state = ISCSI_SESSION_LOGGED_IN;
 585        spin_unlock_irqrestore(&session->lock, flags);
 586        /* start IO */
 587        scsi_target_unblock(&session->dev);
 588        /*
 589         * Only do kernel scanning if the driver is properly hooked into
 590         * the async scanning code (drivers like iscsi_tcp do login and
 591         * scanning from userspace).
 592         */
 593        if (shost->hostt->scan_finished) {
 594                if (scsi_queue_work(shost, &session->scan_work))
 595                        atomic_inc(&ihost->nr_scans);
 596        }
 597        ISCSI_DBG_TRANS_SESSION(session, "Completed unblocking session\n");
 598}
 599
 600/**
 601 * iscsi_unblock_session - set a session as logged in and start IO.
 602 * @session: iscsi session
 603 *
 604 * Mark a session as ready to accept IO.
 605 */
 606void iscsi_unblock_session(struct iscsi_cls_session *session)
 607{
 608        queue_work(iscsi_eh_timer_workq, &session->unblock_work);
 609        /*
 610         * make sure all the events have completed before tell the driver
 611         * it is safe
 612         */
 613        flush_workqueue(iscsi_eh_timer_workq);
 614}
 615EXPORT_SYMBOL_GPL(iscsi_unblock_session);
 616
 617static void __iscsi_block_session(struct work_struct *work)
 618{
 619        struct iscsi_cls_session *session =
 620                        container_of(work, struct iscsi_cls_session,
 621                                     block_work);
 622        unsigned long flags;
 623
 624        ISCSI_DBG_TRANS_SESSION(session, "Blocking session\n");
 625        spin_lock_irqsave(&session->lock, flags);
 626        session->state = ISCSI_SESSION_FAILED;
 627        spin_unlock_irqrestore(&session->lock, flags);
 628        scsi_target_block(&session->dev);
 629        ISCSI_DBG_TRANS_SESSION(session, "Completed SCSI target blocking\n");
 630        queue_delayed_work(iscsi_eh_timer_workq, &session->recovery_work,
 631                           session->recovery_tmo * HZ);
 632}
 633
 634void iscsi_block_session(struct iscsi_cls_session *session)
 635{
 636        queue_work(iscsi_eh_timer_workq, &session->block_work);
 637}
 638EXPORT_SYMBOL_GPL(iscsi_block_session);
 639
 640static void __iscsi_unbind_session(struct work_struct *work)
 641{
 642        struct iscsi_cls_session *session =
 643                        container_of(work, struct iscsi_cls_session,
 644                                     unbind_work);
 645        struct Scsi_Host *shost = iscsi_session_to_shost(session);
 646        struct iscsi_cls_host *ihost = shost->shost_data;
 647        unsigned long flags;
 648
 649        ISCSI_DBG_TRANS_SESSION(session, "Unbinding session\n");
 650
 651        /* Prevent new scans and make sure scanning is not in progress */
 652        mutex_lock(&ihost->mutex);
 653        spin_lock_irqsave(&session->lock, flags);
 654        if (session->target_id == ISCSI_MAX_TARGET) {
 655                spin_unlock_irqrestore(&session->lock, flags);
 656                mutex_unlock(&ihost->mutex);
 657                return;
 658        }
 659        session->target_id = ISCSI_MAX_TARGET;
 660        spin_unlock_irqrestore(&session->lock, flags);
 661        mutex_unlock(&ihost->mutex);
 662
 663        scsi_remove_target(&session->dev);
 664        iscsi_session_event(session, ISCSI_KEVENT_UNBIND_SESSION);
 665        ISCSI_DBG_TRANS_SESSION(session, "Completed target removal\n");
 666}
 667
 668struct iscsi_cls_session *
 669iscsi_alloc_session(struct Scsi_Host *shost, struct iscsi_transport *transport,
 670                    int dd_size)
 671{
 672        struct iscsi_cls_session *session;
 673
 674        session = kzalloc(sizeof(*session) + dd_size,
 675                          GFP_KERNEL);
 676        if (!session)
 677                return NULL;
 678
 679        session->transport = transport;
 680        session->recovery_tmo = 120;
 681        session->state = ISCSI_SESSION_FREE;
 682        INIT_DELAYED_WORK(&session->recovery_work, session_recovery_timedout);
 683        INIT_LIST_HEAD(&session->sess_list);
 684        INIT_WORK(&session->unblock_work, __iscsi_unblock_session);
 685        INIT_WORK(&session->block_work, __iscsi_block_session);
 686        INIT_WORK(&session->unbind_work, __iscsi_unbind_session);
 687        INIT_WORK(&session->scan_work, iscsi_scan_session);
 688        spin_lock_init(&session->lock);
 689
 690        /* this is released in the dev's release function */
 691        scsi_host_get(shost);
 692        session->dev.parent = &shost->shost_gendev;
 693        session->dev.release = iscsi_session_release;
 694        device_initialize(&session->dev);
 695        if (dd_size)
 696                session->dd_data = &session[1];
 697
 698        ISCSI_DBG_TRANS_SESSION(session, "Completed session allocation\n");
 699        return session;
 700}
 701EXPORT_SYMBOL_GPL(iscsi_alloc_session);
 702
 703static int iscsi_get_next_target_id(struct device *dev, void *data)
 704{
 705        struct iscsi_cls_session *session;
 706        unsigned long flags;
 707        int err = 0;
 708
 709        if (!iscsi_is_session_dev(dev))
 710                return 0;
 711
 712        session = iscsi_dev_to_session(dev);
 713        spin_lock_irqsave(&session->lock, flags);
 714        if (*((unsigned int *) data) == session->target_id)
 715                err = -EEXIST;
 716        spin_unlock_irqrestore(&session->lock, flags);
 717        return err;
 718}
 719
 720int iscsi_add_session(struct iscsi_cls_session *session, unsigned int target_id)
 721{
 722        struct Scsi_Host *shost = iscsi_session_to_shost(session);
 723        struct iscsi_cls_host *ihost;
 724        unsigned long flags;
 725        unsigned int id = target_id;
 726        int err;
 727
 728        ihost = shost->shost_data;
 729        session->sid = atomic_add_return(1, &iscsi_session_nr);
 730
 731        if (id == ISCSI_MAX_TARGET) {
 732                for (id = 0; id < ISCSI_MAX_TARGET; id++) {
 733                        err = device_for_each_child(&shost->shost_gendev, &id,
 734                                                    iscsi_get_next_target_id);
 735                        if (!err)
 736                                break;
 737                }
 738
 739                if (id == ISCSI_MAX_TARGET) {
 740                        iscsi_cls_session_printk(KERN_ERR, session,
 741                                                 "Too many iscsi targets. Max "
 742                                                 "number of targets is %d.\n",
 743                                                 ISCSI_MAX_TARGET - 1);
 744                        err = -EOVERFLOW;
 745                        goto release_host;
 746                }
 747        }
 748        session->target_id = id;
 749
 750        dev_set_name(&session->dev, "session%u", session->sid);
 751        err = device_add(&session->dev);
 752        if (err) {
 753                iscsi_cls_session_printk(KERN_ERR, session,
 754                                         "could not register session's dev\n");
 755                goto release_host;
 756        }
 757        transport_register_device(&session->dev);
 758
 759        spin_lock_irqsave(&sesslock, flags);
 760        list_add(&session->sess_list, &sesslist);
 761        spin_unlock_irqrestore(&sesslock, flags);
 762
 763        iscsi_session_event(session, ISCSI_KEVENT_CREATE_SESSION);
 764        ISCSI_DBG_TRANS_SESSION(session, "Completed session adding\n");
 765        return 0;
 766
 767release_host:
 768        scsi_host_put(shost);
 769        return err;
 770}
 771EXPORT_SYMBOL_GPL(iscsi_add_session);
 772
 773/**
 774 * iscsi_create_session - create iscsi class session
 775 * @shost: scsi host
 776 * @transport: iscsi transport
 777 * @dd_size: private driver data size
 778 * @target_id: which target
 779 *
 780 * This can be called from a LLD or iscsi_transport.
 781 */
 782struct iscsi_cls_session *
 783iscsi_create_session(struct Scsi_Host *shost, struct iscsi_transport *transport,
 784                     int dd_size, unsigned int target_id)
 785{
 786        struct iscsi_cls_session *session;
 787
 788        session = iscsi_alloc_session(shost, transport, dd_size);
 789        if (!session)
 790                return NULL;
 791
 792        if (iscsi_add_session(session, target_id)) {
 793                iscsi_free_session(session);
 794                return NULL;
 795        }
 796        return session;
 797}
 798EXPORT_SYMBOL_GPL(iscsi_create_session);
 799
 800static void iscsi_conn_release(struct device *dev)
 801{
 802        struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev);
 803        struct device *parent = conn->dev.parent;
 804
 805        ISCSI_DBG_TRANS_CONN(conn, "Releasing conn\n");
 806        kfree(conn);
 807        put_device(parent);
 808}
 809
 810static int iscsi_is_conn_dev(const struct device *dev)
 811{
 812        return dev->release == iscsi_conn_release;
 813}
 814
 815static int iscsi_iter_destroy_conn_fn(struct device *dev, void *data)
 816{
 817        if (!iscsi_is_conn_dev(dev))
 818                return 0;
 819        return iscsi_destroy_conn(iscsi_dev_to_conn(dev));
 820}
 821
 822void iscsi_remove_session(struct iscsi_cls_session *session)
 823{
 824        struct Scsi_Host *shost = iscsi_session_to_shost(session);
 825        unsigned long flags;
 826        int err;
 827
 828        ISCSI_DBG_TRANS_SESSION(session, "Removing session\n");
 829
 830        spin_lock_irqsave(&sesslock, flags);
 831        list_del(&session->sess_list);
 832        spin_unlock_irqrestore(&sesslock, flags);
 833
 834        /* make sure there are no blocks/unblocks queued */
 835        flush_workqueue(iscsi_eh_timer_workq);
 836        /* make sure the timedout callout is not running */
 837        if (!cancel_delayed_work(&session->recovery_work))
 838                flush_workqueue(iscsi_eh_timer_workq);
 839        /*
 840         * If we are blocked let commands flow again. The lld or iscsi
 841         * layer should set up the queuecommand to fail commands.
 842         * We assume that LLD will not be calling block/unblock while
 843         * removing the session.
 844         */
 845        spin_lock_irqsave(&session->lock, flags);
 846        session->state = ISCSI_SESSION_FREE;
 847        spin_unlock_irqrestore(&session->lock, flags);
 848
 849        scsi_target_unblock(&session->dev);
 850        /* flush running scans then delete devices */
 851        scsi_flush_work(shost);
 852        __iscsi_unbind_session(&session->unbind_work);
 853
 854        /* hw iscsi may not have removed all connections from session */
 855        err = device_for_each_child(&session->dev, NULL,
 856                                    iscsi_iter_destroy_conn_fn);
 857        if (err)
 858                iscsi_cls_session_printk(KERN_ERR, session,
 859                                         "Could not delete all connections "
 860                                         "for session. Error %d.\n", err);
 861
 862        transport_unregister_device(&session->dev);
 863
 864        ISCSI_DBG_TRANS_SESSION(session, "Completing session removal\n");
 865        device_del(&session->dev);
 866}
 867EXPORT_SYMBOL_GPL(iscsi_remove_session);
 868
 869void iscsi_free_session(struct iscsi_cls_session *session)
 870{
 871        ISCSI_DBG_TRANS_SESSION(session, "Freeing session\n");
 872        iscsi_session_event(session, ISCSI_KEVENT_DESTROY_SESSION);
 873        put_device(&session->dev);
 874}
 875EXPORT_SYMBOL_GPL(iscsi_free_session);
 876
 877/**
 878 * iscsi_destroy_session - destroy iscsi session
 879 * @session: iscsi_session
 880 *
 881 * Can be called by a LLD or iscsi_transport. There must not be
 882 * any running connections.
 883 */
 884int iscsi_destroy_session(struct iscsi_cls_session *session)
 885{
 886        iscsi_remove_session(session);
 887        ISCSI_DBG_TRANS_SESSION(session, "Completing session destruction\n");
 888        iscsi_free_session(session);
 889        return 0;
 890}
 891EXPORT_SYMBOL_GPL(iscsi_destroy_session);
 892
 893/**
 894 * iscsi_create_conn - create iscsi class connection
 895 * @session: iscsi cls session
 896 * @dd_size: private driver data size
 897 * @cid: connection id
 898 *
 899 * This can be called from a LLD or iscsi_transport. The connection
 900 * is child of the session so cid must be unique for all connections
 901 * on the session.
 902 *
 903 * Since we do not support MCS, cid will normally be zero. In some cases
 904 * for software iscsi we could be trying to preallocate a connection struct
 905 * in which case there could be two connection structs and cid would be
 906 * non-zero.
 907 */
 908struct iscsi_cls_conn *
 909iscsi_create_conn(struct iscsi_cls_session *session, int dd_size, uint32_t cid)
 910{
 911        struct iscsi_transport *transport = session->transport;
 912        struct iscsi_cls_conn *conn;
 913        unsigned long flags;
 914        int err;
 915
 916        conn = kzalloc(sizeof(*conn) + dd_size, GFP_KERNEL);
 917        if (!conn)
 918                return NULL;
 919        if (dd_size)
 920                conn->dd_data = &conn[1];
 921
 922        INIT_LIST_HEAD(&conn->conn_list);
 923        conn->transport = transport;
 924        conn->cid = cid;
 925
 926        /* this is released in the dev's release function */
 927        if (!get_device(&session->dev))
 928                goto free_conn;
 929
 930        dev_set_name(&conn->dev, "connection%d:%u", session->sid, cid);
 931        conn->dev.parent = &session->dev;
 932        conn->dev.release = iscsi_conn_release;
 933        err = device_register(&conn->dev);
 934        if (err) {
 935                iscsi_cls_session_printk(KERN_ERR, session, "could not "
 936                                         "register connection's dev\n");
 937                goto release_parent_ref;
 938        }
 939        transport_register_device(&conn->dev);
 940
 941        spin_lock_irqsave(&connlock, flags);
 942        list_add(&conn->conn_list, &connlist);
 943        conn->active = 1;
 944        spin_unlock_irqrestore(&connlock, flags);
 945
 946        ISCSI_DBG_TRANS_CONN(conn, "Completed conn creation\n");
 947        return conn;
 948
 949release_parent_ref:
 950        put_device(&session->dev);
 951free_conn:
 952        kfree(conn);
 953        return NULL;
 954}
 955
 956EXPORT_SYMBOL_GPL(iscsi_create_conn);
 957
 958/**
 959 * iscsi_destroy_conn - destroy iscsi class connection
 960 * @conn: iscsi cls session
 961 *
 962 * This can be called from a LLD or iscsi_transport.
 963 */
 964int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
 965{
 966        unsigned long flags;
 967
 968        spin_lock_irqsave(&connlock, flags);
 969        conn->active = 0;
 970        list_del(&conn->conn_list);
 971        spin_unlock_irqrestore(&connlock, flags);
 972
 973        transport_unregister_device(&conn->dev);
 974        ISCSI_DBG_TRANS_CONN(conn, "Completing conn destruction\n");
 975        device_unregister(&conn->dev);
 976        return 0;
 977}
 978EXPORT_SYMBOL_GPL(iscsi_destroy_conn);
 979
 980/*
 981 * iscsi interface functions
 982 */
 983static struct iscsi_internal *
 984iscsi_if_transport_lookup(struct iscsi_transport *tt)
 985{
 986        struct iscsi_internal *priv;
 987        unsigned long flags;
 988
 989        spin_lock_irqsave(&iscsi_transport_lock, flags);
 990        list_for_each_entry(priv, &iscsi_transports, list) {
 991                if (tt == priv->iscsi_transport) {
 992                        spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 993                        return priv;
 994                }
 995        }
 996        spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 997        return NULL;
 998}
 999
1000static int
1001iscsi_multicast_skb(struct sk_buff *skb, uint32_t group, gfp_t gfp)
1002{
1003        return nlmsg_multicast(nls, skb, 0, group, gfp);
1004}
1005
1006int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
1007                   char *data, uint32_t data_size)
1008{
1009        struct nlmsghdr *nlh;
1010        struct sk_buff *skb;
1011        struct iscsi_uevent *ev;
1012        char *pdu;
1013        struct iscsi_internal *priv;
1014        int len = NLMSG_SPACE(sizeof(*ev) + sizeof(struct iscsi_hdr) +
1015                              data_size);
1016
1017        priv = iscsi_if_transport_lookup(conn->transport);
1018        if (!priv)
1019                return -EINVAL;
1020
1021        skb = alloc_skb(len, GFP_ATOMIC);
1022        if (!skb) {
1023                iscsi_conn_error_event(conn, ISCSI_ERR_CONN_FAILED);
1024                iscsi_cls_conn_printk(KERN_ERR, conn, "can not deliver "
1025                                      "control PDU: OOM\n");
1026                return -ENOMEM;
1027        }
1028
1029        nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1030        ev = NLMSG_DATA(nlh);
1031        memset(ev, 0, sizeof(*ev));
1032        ev->transport_handle = iscsi_handle(conn->transport);
1033        ev->type = ISCSI_KEVENT_RECV_PDU;
1034        ev->r.recv_req.cid = conn->cid;
1035        ev->r.recv_req.sid = iscsi_conn_get_sid(conn);
1036        pdu = (char*)ev + sizeof(*ev);
1037        memcpy(pdu, hdr, sizeof(struct iscsi_hdr));
1038        memcpy(pdu + sizeof(struct iscsi_hdr), data, data_size);
1039
1040        return iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_ATOMIC);
1041}
1042EXPORT_SYMBOL_GPL(iscsi_recv_pdu);
1043
1044int iscsi_offload_mesg(struct Scsi_Host *shost,
1045                       struct iscsi_transport *transport, uint32_t type,
1046                       char *data, uint16_t data_size)
1047{
1048        struct nlmsghdr *nlh;
1049        struct sk_buff *skb;
1050        struct iscsi_uevent *ev;
1051        int len = NLMSG_SPACE(sizeof(*ev) + data_size);
1052
1053        skb = alloc_skb(len, GFP_ATOMIC);
1054        if (!skb) {
1055                printk(KERN_ERR "can not deliver iscsi offload message:OOM\n");
1056                return -ENOMEM;
1057        }
1058
1059        nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1060        ev = NLMSG_DATA(nlh);
1061        memset(ev, 0, sizeof(*ev));
1062        ev->type = type;
1063        ev->transport_handle = iscsi_handle(transport);
1064        switch (type) {
1065        case ISCSI_KEVENT_PATH_REQ:
1066                ev->r.req_path.host_no = shost->host_no;
1067                break;
1068        case ISCSI_KEVENT_IF_DOWN:
1069                ev->r.notify_if_down.host_no = shost->host_no;
1070                break;
1071        }
1072
1073        memcpy((char *)ev + sizeof(*ev), data, data_size);
1074
1075        return iscsi_multicast_skb(skb, ISCSI_NL_GRP_UIP, GFP_ATOMIC);
1076}
1077EXPORT_SYMBOL_GPL(iscsi_offload_mesg);
1078
1079void iscsi_conn_error_event(struct iscsi_cls_conn *conn, enum iscsi_err error)
1080{
1081        struct nlmsghdr *nlh;
1082        struct sk_buff  *skb;
1083        struct iscsi_uevent *ev;
1084        struct iscsi_internal *priv;
1085        int len = NLMSG_SPACE(sizeof(*ev));
1086
1087        priv = iscsi_if_transport_lookup(conn->transport);
1088        if (!priv)
1089                return;
1090
1091        skb = alloc_skb(len, GFP_ATOMIC);
1092        if (!skb) {
1093                iscsi_cls_conn_printk(KERN_ERR, conn, "gracefully ignored "
1094                                      "conn error (%d)\n", error);
1095                return;
1096        }
1097
1098        nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1099        ev = NLMSG_DATA(nlh);
1100        ev->transport_handle = iscsi_handle(conn->transport);
1101        ev->type = ISCSI_KEVENT_CONN_ERROR;
1102        ev->r.connerror.error = error;
1103        ev->r.connerror.cid = conn->cid;
1104        ev->r.connerror.sid = iscsi_conn_get_sid(conn);
1105
1106        iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_ATOMIC);
1107
1108        iscsi_cls_conn_printk(KERN_INFO, conn, "detected conn error (%d)\n",
1109                              error);
1110}
1111EXPORT_SYMBOL_GPL(iscsi_conn_error_event);
1112
1113static int
1114iscsi_if_send_reply(uint32_t group, int seq, int type, int done, int multi,
1115                    void *payload, int size)
1116{
1117        struct sk_buff  *skb;
1118        struct nlmsghdr *nlh;
1119        int len = NLMSG_SPACE(size);
1120        int flags = multi ? NLM_F_MULTI : 0;
1121        int t = done ? NLMSG_DONE : type;
1122
1123        skb = alloc_skb(len, GFP_ATOMIC);
1124        if (!skb) {
1125                printk(KERN_ERR "Could not allocate skb to send reply.\n");
1126                return -ENOMEM;
1127        }
1128
1129        nlh = __nlmsg_put(skb, 0, 0, t, (len - sizeof(*nlh)), 0);
1130        nlh->nlmsg_flags = flags;
1131        memcpy(NLMSG_DATA(nlh), payload, size);
1132        return iscsi_multicast_skb(skb, group, GFP_ATOMIC);
1133}
1134
1135static int
1136iscsi_if_get_stats(struct iscsi_transport *transport, struct nlmsghdr *nlh)
1137{
1138        struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1139        struct iscsi_stats *stats;
1140        struct sk_buff *skbstat;
1141        struct iscsi_cls_conn *conn;
1142        struct nlmsghdr *nlhstat;
1143        struct iscsi_uevent *evstat;
1144        struct iscsi_internal *priv;
1145        int len = NLMSG_SPACE(sizeof(*ev) +
1146                              sizeof(struct iscsi_stats) +
1147                              sizeof(struct iscsi_stats_custom) *
1148                              ISCSI_STATS_CUSTOM_MAX);
1149        int err = 0;
1150
1151        priv = iscsi_if_transport_lookup(transport);
1152        if (!priv)
1153                return -EINVAL;
1154
1155        conn = iscsi_conn_lookup(ev->u.get_stats.sid, ev->u.get_stats.cid);
1156        if (!conn)
1157                return -EEXIST;
1158
1159        do {
1160                int actual_size;
1161
1162                skbstat = alloc_skb(len, GFP_ATOMIC);
1163                if (!skbstat) {
1164                        iscsi_cls_conn_printk(KERN_ERR, conn, "can not "
1165                                              "deliver stats: OOM\n");
1166                        return -ENOMEM;
1167                }
1168
1169                nlhstat = __nlmsg_put(skbstat, 0, 0, 0,
1170                                      (len - sizeof(*nlhstat)), 0);
1171                evstat = NLMSG_DATA(nlhstat);
1172                memset(evstat, 0, sizeof(*evstat));
1173                evstat->transport_handle = iscsi_handle(conn->transport);
1174                evstat->type = nlh->nlmsg_type;
1175                evstat->u.get_stats.cid =
1176                        ev->u.get_stats.cid;
1177                evstat->u.get_stats.sid =
1178                        ev->u.get_stats.sid;
1179                stats = (struct iscsi_stats *)
1180                        ((char*)evstat + sizeof(*evstat));
1181                memset(stats, 0, sizeof(*stats));
1182
1183                transport->get_stats(conn, stats);
1184                actual_size = NLMSG_SPACE(sizeof(struct iscsi_uevent) +
1185                                          sizeof(struct iscsi_stats) +
1186                                          sizeof(struct iscsi_stats_custom) *
1187                                          stats->custom_length);
1188                actual_size -= sizeof(*nlhstat);
1189                actual_size = NLMSG_LENGTH(actual_size);
1190                skb_trim(skbstat, NLMSG_ALIGN(actual_size));
1191                nlhstat->nlmsg_len = actual_size;
1192
1193                err = iscsi_multicast_skb(skbstat, ISCSI_NL_GRP_ISCSID,
1194                                          GFP_ATOMIC);
1195        } while (err < 0 && err != -ECONNREFUSED);
1196
1197        return err;
1198}
1199
1200/**
1201 * iscsi_session_event - send session destr. completion event
1202 * @session: iscsi class session
1203 * @event: type of event
1204 */
1205int iscsi_session_event(struct iscsi_cls_session *session,
1206                        enum iscsi_uevent_e event)
1207{
1208        struct iscsi_internal *priv;
1209        struct Scsi_Host *shost;
1210        struct iscsi_uevent *ev;
1211        struct sk_buff  *skb;
1212        struct nlmsghdr *nlh;
1213        int rc, len = NLMSG_SPACE(sizeof(*ev));
1214
1215        priv = iscsi_if_transport_lookup(session->transport);
1216        if (!priv)
1217                return -EINVAL;
1218        shost = iscsi_session_to_shost(session);
1219
1220        skb = alloc_skb(len, GFP_KERNEL);
1221        if (!skb) {
1222                iscsi_cls_session_printk(KERN_ERR, session,
1223                                         "Cannot notify userspace of session "
1224                                         "event %u\n", event);
1225                return -ENOMEM;
1226        }
1227
1228        nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1229        ev = NLMSG_DATA(nlh);
1230        ev->transport_handle = iscsi_handle(session->transport);
1231
1232        ev->type = event;
1233        switch (event) {
1234        case ISCSI_KEVENT_DESTROY_SESSION:
1235                ev->r.d_session.host_no = shost->host_no;
1236                ev->r.d_session.sid = session->sid;
1237                break;
1238        case ISCSI_KEVENT_CREATE_SESSION:
1239                ev->r.c_session_ret.host_no = shost->host_no;
1240                ev->r.c_session_ret.sid = session->sid;
1241                break;
1242        case ISCSI_KEVENT_UNBIND_SESSION:
1243                ev->r.unbind_session.host_no = shost->host_no;
1244                ev->r.unbind_session.sid = session->sid;
1245                break;
1246        default:
1247                iscsi_cls_session_printk(KERN_ERR, session, "Invalid event "
1248                                         "%u.\n", event);
1249                kfree_skb(skb);
1250                return -EINVAL;
1251        }
1252
1253        /*
1254         * this will occur if the daemon is not up, so we just warn
1255         * the user and when the daemon is restarted it will handle it
1256         */
1257        rc = iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_KERNEL);
1258        if (rc == -ESRCH)
1259                iscsi_cls_session_printk(KERN_ERR, session,
1260                                         "Cannot notify userspace of session "
1261                                         "event %u. Check iscsi daemon\n",
1262                                         event);
1263
1264        ISCSI_DBG_TRANS_SESSION(session, "Completed handling event %d rc %d\n",
1265                                event, rc);
1266        return rc;
1267}
1268EXPORT_SYMBOL_GPL(iscsi_session_event);
1269
1270static int
1271iscsi_if_create_session(struct iscsi_internal *priv, struct iscsi_endpoint *ep,
1272                        struct iscsi_uevent *ev, uint32_t initial_cmdsn,
1273                        uint16_t cmds_max, uint16_t queue_depth)
1274{
1275        struct iscsi_transport *transport = priv->iscsi_transport;
1276        struct iscsi_cls_session *session;
1277        struct Scsi_Host *shost;
1278
1279        session = transport->create_session(ep, cmds_max, queue_depth,
1280                                            initial_cmdsn);
1281        if (!session)
1282                return -ENOMEM;
1283
1284        shost = iscsi_session_to_shost(session);
1285        ev->r.c_session_ret.host_no = shost->host_no;
1286        ev->r.c_session_ret.sid = session->sid;
1287        ISCSI_DBG_TRANS_SESSION(session,
1288                                "Completed creating transport session\n");
1289        return 0;
1290}
1291
1292static int
1293iscsi_if_create_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1294{
1295        struct iscsi_cls_conn *conn;
1296        struct iscsi_cls_session *session;
1297
1298        session = iscsi_session_lookup(ev->u.c_conn.sid);
1299        if (!session) {
1300                printk(KERN_ERR "iscsi: invalid session %d.\n",
1301                       ev->u.c_conn.sid);
1302                return -EINVAL;
1303        }
1304
1305        conn = transport->create_conn(session, ev->u.c_conn.cid);
1306        if (!conn) {
1307                iscsi_cls_session_printk(KERN_ERR, session,
1308                                         "couldn't create a new connection.");
1309                return -ENOMEM;
1310        }
1311
1312        ev->r.c_conn_ret.sid = session->sid;
1313        ev->r.c_conn_ret.cid = conn->cid;
1314
1315        ISCSI_DBG_TRANS_CONN(conn, "Completed creating transport conn\n");
1316        return 0;
1317}
1318
1319static int
1320iscsi_if_destroy_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1321{
1322        struct iscsi_cls_conn *conn;
1323
1324        conn = iscsi_conn_lookup(ev->u.d_conn.sid, ev->u.d_conn.cid);
1325        if (!conn)
1326                return -EINVAL;
1327
1328        ISCSI_DBG_TRANS_CONN(conn, "Destroying transport conn\n");
1329        if (transport->destroy_conn)
1330                transport->destroy_conn(conn);
1331
1332        return 0;
1333}
1334
1335static int
1336iscsi_set_param(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1337{
1338        char *data = (char*)ev + sizeof(*ev);
1339        struct iscsi_cls_conn *conn;
1340        struct iscsi_cls_session *session;
1341        int err = 0, value = 0;
1342
1343        session = iscsi_session_lookup(ev->u.set_param.sid);
1344        conn = iscsi_conn_lookup(ev->u.set_param.sid, ev->u.set_param.cid);
1345        if (!conn || !session)
1346                return -EINVAL;
1347
1348        switch (ev->u.set_param.param) {
1349        case ISCSI_PARAM_SESS_RECOVERY_TMO:
1350                sscanf(data, "%d", &value);
1351                if (value != 0)
1352                        session->recovery_tmo = value;
1353                break;
1354        default:
1355                err = transport->set_param(conn, ev->u.set_param.param,
1356                                           data, ev->u.set_param.len);
1357        }
1358
1359        return err;
1360}
1361
1362static int iscsi_if_ep_connect(struct iscsi_transport *transport,
1363                               struct iscsi_uevent *ev, int msg_type)
1364{
1365        struct iscsi_endpoint *ep;
1366        struct sockaddr *dst_addr;
1367        struct Scsi_Host *shost = NULL;
1368        int non_blocking, err = 0;
1369
1370        if (!transport->ep_connect)
1371                return -EINVAL;
1372
1373        if (msg_type == ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST) {
1374                shost = scsi_host_lookup(ev->u.ep_connect_through_host.host_no);
1375                if (!shost) {
1376                        printk(KERN_ERR "ep connect failed. Could not find "
1377                               "host no %u\n",
1378                               ev->u.ep_connect_through_host.host_no);
1379                        return -ENODEV;
1380                }
1381                non_blocking = ev->u.ep_connect_through_host.non_blocking;
1382        } else
1383                non_blocking = ev->u.ep_connect.non_blocking;
1384
1385        dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1386        ep = transport->ep_connect(shost, dst_addr, non_blocking);
1387        if (IS_ERR(ep)) {
1388                err = PTR_ERR(ep);
1389                goto release_host;
1390        }
1391
1392        ev->r.ep_connect_ret.handle = ep->id;
1393release_host:
1394        if (shost)
1395                scsi_host_put(shost);
1396        return err;
1397}
1398
1399static int
1400iscsi_if_transport_ep(struct iscsi_transport *transport,
1401                      struct iscsi_uevent *ev, int msg_type)
1402{
1403        struct iscsi_endpoint *ep;
1404        int rc = 0;
1405
1406        switch (msg_type) {
1407        case ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST:
1408        case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1409                rc = iscsi_if_ep_connect(transport, ev, msg_type);
1410                break;
1411        case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1412                if (!transport->ep_poll)
1413                        return -EINVAL;
1414
1415                ep = iscsi_lookup_endpoint(ev->u.ep_poll.ep_handle);
1416                if (!ep)
1417                        return -EINVAL;
1418
1419                ev->r.retcode = transport->ep_poll(ep,
1420                                                   ev->u.ep_poll.timeout_ms);
1421                break;
1422        case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1423                if (!transport->ep_disconnect)
1424                        return -EINVAL;
1425
1426                ep = iscsi_lookup_endpoint(ev->u.ep_disconnect.ep_handle);
1427                if (!ep)
1428                        return -EINVAL;
1429
1430                transport->ep_disconnect(ep);
1431                break;
1432        }
1433        return rc;
1434}
1435
1436static int
1437iscsi_tgt_dscvr(struct iscsi_transport *transport,
1438                struct iscsi_uevent *ev)
1439{
1440        struct Scsi_Host *shost;
1441        struct sockaddr *dst_addr;
1442        int err;
1443
1444        if (!transport->tgt_dscvr)
1445                return -EINVAL;
1446
1447        shost = scsi_host_lookup(ev->u.tgt_dscvr.host_no);
1448        if (!shost) {
1449                printk(KERN_ERR "target discovery could not find host no %u\n",
1450                       ev->u.tgt_dscvr.host_no);
1451                return -ENODEV;
1452        }
1453
1454
1455        dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1456        err = transport->tgt_dscvr(shost, ev->u.tgt_dscvr.type,
1457                                   ev->u.tgt_dscvr.enable, dst_addr);
1458        scsi_host_put(shost);
1459        return err;
1460}
1461
1462static int
1463iscsi_set_host_param(struct iscsi_transport *transport,
1464                     struct iscsi_uevent *ev)
1465{
1466        char *data = (char*)ev + sizeof(*ev);
1467        struct Scsi_Host *shost;
1468        int err;
1469
1470        if (!transport->set_host_param)
1471                return -ENOSYS;
1472
1473        shost = scsi_host_lookup(ev->u.set_host_param.host_no);
1474        if (!shost) {
1475                printk(KERN_ERR "set_host_param could not find host no %u\n",
1476                       ev->u.set_host_param.host_no);
1477                return -ENODEV;
1478        }
1479
1480        err = transport->set_host_param(shost, ev->u.set_host_param.param,
1481                                        data, ev->u.set_host_param.len);
1482        scsi_host_put(shost);
1483        return err;
1484}
1485
1486static int
1487iscsi_set_path(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1488{
1489        struct Scsi_Host *shost;
1490        struct iscsi_path *params;
1491        int err;
1492
1493        if (!transport->set_path)
1494                return -ENOSYS;
1495
1496        shost = scsi_host_lookup(ev->u.set_path.host_no);
1497        if (!shost) {
1498                printk(KERN_ERR "set path could not find host no %u\n",
1499                       ev->u.set_path.host_no);
1500                return -ENODEV;
1501        }
1502
1503        params = (struct iscsi_path *)((char *)ev + sizeof(*ev));
1504        err = transport->set_path(shost, params);
1505
1506        scsi_host_put(shost);
1507        return err;
1508}
1509
1510static int
1511iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, uint32_t *group)
1512{
1513        int err = 0;
1514        struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1515        struct iscsi_transport *transport = NULL;
1516        struct iscsi_internal *priv;
1517        struct iscsi_cls_session *session;
1518        struct iscsi_cls_conn *conn;
1519        struct iscsi_endpoint *ep = NULL;
1520
1521        if (nlh->nlmsg_type == ISCSI_UEVENT_PATH_UPDATE)
1522                *group = ISCSI_NL_GRP_UIP;
1523        else
1524                *group = ISCSI_NL_GRP_ISCSID;
1525
1526        priv = iscsi_if_transport_lookup(iscsi_ptr(ev->transport_handle));
1527        if (!priv)
1528                return -EINVAL;
1529        transport = priv->iscsi_transport;
1530
1531        if (!try_module_get(transport->owner))
1532                return -EINVAL;
1533
1534        switch (nlh->nlmsg_type) {
1535        case ISCSI_UEVENT_CREATE_SESSION:
1536                err = iscsi_if_create_session(priv, ep, ev,
1537                                              ev->u.c_session.initial_cmdsn,
1538                                              ev->u.c_session.cmds_max,
1539                                              ev->u.c_session.queue_depth);
1540                break;
1541        case ISCSI_UEVENT_CREATE_BOUND_SESSION:
1542                ep = iscsi_lookup_endpoint(ev->u.c_bound_session.ep_handle);
1543                if (!ep) {
1544                        err = -EINVAL;
1545                        break;
1546                }
1547
1548                err = iscsi_if_create_session(priv, ep, ev,
1549                                        ev->u.c_bound_session.initial_cmdsn,
1550                                        ev->u.c_bound_session.cmds_max,
1551                                        ev->u.c_bound_session.queue_depth);
1552                break;
1553        case ISCSI_UEVENT_DESTROY_SESSION:
1554                session = iscsi_session_lookup(ev->u.d_session.sid);
1555                if (session)
1556                        transport->destroy_session(session);
1557                else
1558                        err = -EINVAL;
1559                break;
1560        case ISCSI_UEVENT_UNBIND_SESSION:
1561                session = iscsi_session_lookup(ev->u.d_session.sid);
1562                if (session)
1563                        scsi_queue_work(iscsi_session_to_shost(session),
1564                                        &session->unbind_work);
1565                else
1566                        err = -EINVAL;
1567                break;
1568        case ISCSI_UEVENT_CREATE_CONN:
1569                err = iscsi_if_create_conn(transport, ev);
1570                break;
1571        case ISCSI_UEVENT_DESTROY_CONN:
1572                err = iscsi_if_destroy_conn(transport, ev);
1573                break;
1574        case ISCSI_UEVENT_BIND_CONN:
1575                session = iscsi_session_lookup(ev->u.b_conn.sid);
1576                conn = iscsi_conn_lookup(ev->u.b_conn.sid, ev->u.b_conn.cid);
1577
1578                if (session && conn)
1579                        ev->r.retcode = transport->bind_conn(session, conn,
1580                                        ev->u.b_conn.transport_eph,
1581                                        ev->u.b_conn.is_leading);
1582                else
1583                        err = -EINVAL;
1584                break;
1585        case ISCSI_UEVENT_SET_PARAM:
1586                err = iscsi_set_param(transport, ev);
1587                break;
1588        case ISCSI_UEVENT_START_CONN:
1589                conn = iscsi_conn_lookup(ev->u.start_conn.sid, ev->u.start_conn.cid);
1590                if (conn)
1591                        ev->r.retcode = transport->start_conn(conn);
1592                else
1593                        err = -EINVAL;
1594                break;
1595        case ISCSI_UEVENT_STOP_CONN:
1596                conn = iscsi_conn_lookup(ev->u.stop_conn.sid, ev->u.stop_conn.cid);
1597                if (conn)
1598                        transport->stop_conn(conn, ev->u.stop_conn.flag);
1599                else
1600                        err = -EINVAL;
1601                break;
1602        case ISCSI_UEVENT_SEND_PDU:
1603                conn = iscsi_conn_lookup(ev->u.send_pdu.sid, ev->u.send_pdu.cid);
1604                if (conn)
1605                        ev->r.retcode = transport->send_pdu(conn,
1606                                (struct iscsi_hdr*)((char*)ev + sizeof(*ev)),
1607                                (char*)ev + sizeof(*ev) + ev->u.send_pdu.hdr_size,
1608                                ev->u.send_pdu.data_size);
1609                else
1610                        err = -EINVAL;
1611                break;
1612        case ISCSI_UEVENT_GET_STATS:
1613                err = iscsi_if_get_stats(transport, nlh);
1614                break;
1615        case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1616        case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1617        case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1618        case ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST:
1619                err = iscsi_if_transport_ep(transport, ev, nlh->nlmsg_type);
1620                break;
1621        case ISCSI_UEVENT_TGT_DSCVR:
1622                err = iscsi_tgt_dscvr(transport, ev);
1623                break;
1624        case ISCSI_UEVENT_SET_HOST_PARAM:
1625                err = iscsi_set_host_param(transport, ev);
1626                break;
1627        case ISCSI_UEVENT_PATH_UPDATE:
1628                err = iscsi_set_path(transport, ev);
1629                break;
1630        default:
1631                err = -ENOSYS;
1632                break;
1633        }
1634
1635        module_put(transport->owner);
1636        return err;
1637}
1638
1639/*
1640 * Get message from skb.  Each message is processed by iscsi_if_recv_msg.
1641 * Malformed skbs with wrong lengths or invalid creds are not processed.
1642 */
1643static void
1644iscsi_if_rx(struct sk_buff *skb)
1645{
1646        mutex_lock(&rx_queue_mutex);
1647        while (skb->len >= NLMSG_SPACE(0)) {
1648                int err;
1649                uint32_t rlen;
1650                struct nlmsghdr *nlh;
1651                struct iscsi_uevent *ev;
1652                uint32_t group;
1653
1654                nlh = nlmsg_hdr(skb);
1655                if (nlh->nlmsg_len < sizeof(*nlh) ||
1656                    skb->len < nlh->nlmsg_len) {
1657                        break;
1658                }
1659
1660                ev = NLMSG_DATA(nlh);
1661                rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1662                if (rlen > skb->len)
1663                        rlen = skb->len;
1664
1665                err = iscsi_if_recv_msg(skb, nlh, &group);
1666                if (err) {
1667                        ev->type = ISCSI_KEVENT_IF_ERROR;
1668                        ev->iferror = err;
1669                }
1670                do {
1671                        /*
1672                         * special case for GET_STATS:
1673                         * on success - sending reply and stats from
1674                         * inside of if_recv_msg(),
1675                         * on error - fall through.
1676                         */
1677                        if (ev->type == ISCSI_UEVENT_GET_STATS && !err)
1678                                break;
1679                        err = iscsi_if_send_reply(group, nlh->nlmsg_seq,
1680                                nlh->nlmsg_type, 0, 0, ev, sizeof(*ev));
1681                } while (err < 0 && err != -ECONNREFUSED);
1682                skb_pull(skb, rlen);
1683        }
1684        mutex_unlock(&rx_queue_mutex);
1685}
1686
1687#define ISCSI_CLASS_ATTR(_prefix,_name,_mode,_show,_store)              \
1688struct device_attribute dev_attr_##_prefix##_##_name =  \
1689        __ATTR(_name,_mode,_show,_store)
1690
1691/*
1692 * iSCSI connection attrs
1693 */
1694#define iscsi_conn_attr_show(param)                                     \
1695static ssize_t                                                          \
1696show_conn_param_##param(struct device *dev,                             \
1697                        struct device_attribute *attr, char *buf)       \
1698{                                                                       \
1699        struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev->parent);   \
1700        struct iscsi_transport *t = conn->transport;                    \
1701        return t->get_conn_param(conn, param, buf);                     \
1702}
1703
1704#define iscsi_conn_attr(field, param)                                   \
1705        iscsi_conn_attr_show(param)                                     \
1706static ISCSI_CLASS_ATTR(conn, field, S_IRUGO, show_conn_param_##param,  \
1707                        NULL);
1708
1709iscsi_conn_attr(max_recv_dlength, ISCSI_PARAM_MAX_RECV_DLENGTH);
1710iscsi_conn_attr(max_xmit_dlength, ISCSI_PARAM_MAX_XMIT_DLENGTH);
1711iscsi_conn_attr(header_digest, ISCSI_PARAM_HDRDGST_EN);
1712iscsi_conn_attr(data_digest, ISCSI_PARAM_DATADGST_EN);
1713iscsi_conn_attr(ifmarker, ISCSI_PARAM_IFMARKER_EN);
1714iscsi_conn_attr(ofmarker, ISCSI_PARAM_OFMARKER_EN);
1715iscsi_conn_attr(persistent_port, ISCSI_PARAM_PERSISTENT_PORT);
1716iscsi_conn_attr(port, ISCSI_PARAM_CONN_PORT);
1717iscsi_conn_attr(exp_statsn, ISCSI_PARAM_EXP_STATSN);
1718iscsi_conn_attr(persistent_address, ISCSI_PARAM_PERSISTENT_ADDRESS);
1719iscsi_conn_attr(address, ISCSI_PARAM_CONN_ADDRESS);
1720iscsi_conn_attr(ping_tmo, ISCSI_PARAM_PING_TMO);
1721iscsi_conn_attr(recv_tmo, ISCSI_PARAM_RECV_TMO);
1722
1723/*
1724 * iSCSI session attrs
1725 */
1726#define iscsi_session_attr_show(param, perm)                            \
1727static ssize_t                                                          \
1728show_session_param_##param(struct device *dev,                          \
1729                           struct device_attribute *attr, char *buf)    \
1730{                                                                       \
1731        struct iscsi_cls_session *session =                             \
1732                iscsi_dev_to_session(dev->parent);                      \
1733        struct iscsi_transport *t = session->transport;                 \
1734                                                                        \
1735        if (perm && !capable(CAP_SYS_ADMIN))                            \
1736                return -EACCES;                                         \
1737        return t->get_session_param(session, param, buf);               \
1738}
1739
1740#define iscsi_session_attr(field, param, perm)                          \
1741        iscsi_session_attr_show(param, perm)                            \
1742static ISCSI_CLASS_ATTR(sess, field, S_IRUGO, show_session_param_##param, \
1743                        NULL);
1744
1745iscsi_session_attr(targetname, ISCSI_PARAM_TARGET_NAME, 0);
1746iscsi_session_attr(initial_r2t, ISCSI_PARAM_INITIAL_R2T_EN, 0);
1747iscsi_session_attr(max_outstanding_r2t, ISCSI_PARAM_MAX_R2T, 0);
1748iscsi_session_attr(immediate_data, ISCSI_PARAM_IMM_DATA_EN, 0);
1749iscsi_session_attr(first_burst_len, ISCSI_PARAM_FIRST_BURST, 0);
1750iscsi_session_attr(max_burst_len, ISCSI_PARAM_MAX_BURST, 0);
1751iscsi_session_attr(data_pdu_in_order, ISCSI_PARAM_PDU_INORDER_EN, 0);
1752iscsi_session_attr(data_seq_in_order, ISCSI_PARAM_DATASEQ_INORDER_EN, 0);
1753iscsi_session_attr(erl, ISCSI_PARAM_ERL, 0);
1754iscsi_session_attr(tpgt, ISCSI_PARAM_TPGT, 0);
1755iscsi_session_attr(username, ISCSI_PARAM_USERNAME, 1);
1756iscsi_session_attr(username_in, ISCSI_PARAM_USERNAME_IN, 1);
1757iscsi_session_attr(password, ISCSI_PARAM_PASSWORD, 1);
1758iscsi_session_attr(password_in, ISCSI_PARAM_PASSWORD_IN, 1);
1759iscsi_session_attr(fast_abort, ISCSI_PARAM_FAST_ABORT, 0);
1760iscsi_session_attr(abort_tmo, ISCSI_PARAM_ABORT_TMO, 0);
1761iscsi_session_attr(lu_reset_tmo, ISCSI_PARAM_LU_RESET_TMO, 0);
1762iscsi_session_attr(ifacename, ISCSI_PARAM_IFACE_NAME, 0);
1763iscsi_session_attr(initiatorname, ISCSI_PARAM_INITIATOR_NAME, 0)
1764
1765static ssize_t
1766show_priv_session_state(struct device *dev, struct device_attribute *attr,
1767                        char *buf)
1768{
1769        struct iscsi_cls_session *session = iscsi_dev_to_session(dev->parent);
1770        return sprintf(buf, "%s\n", iscsi_session_state_name(session->state));
1771}
1772static ISCSI_CLASS_ATTR(priv_sess, state, S_IRUGO, show_priv_session_state,
1773                        NULL);
1774
1775#define iscsi_priv_session_attr_show(field, format)                     \
1776static ssize_t                                                          \
1777show_priv_session_##field(struct device *dev,                           \
1778                          struct device_attribute *attr, char *buf)     \
1779{                                                                       \
1780        struct iscsi_cls_session *session =                             \
1781                        iscsi_dev_to_session(dev->parent);              \
1782        return sprintf(buf, format"\n", session->field);                \
1783}
1784
1785#define iscsi_priv_session_attr(field, format)                          \
1786        iscsi_priv_session_attr_show(field, format)                     \
1787static ISCSI_CLASS_ATTR(priv_sess, field, S_IRUGO, show_priv_session_##field, \
1788                        NULL)
1789iscsi_priv_session_attr(recovery_tmo, "%d");
1790
1791/*
1792 * iSCSI host attrs
1793 */
1794#define iscsi_host_attr_show(param)                                     \
1795static ssize_t                                                          \
1796show_host_param_##param(struct device *dev,                             \
1797                        struct device_attribute *attr, char *buf)       \
1798{                                                                       \
1799        struct Scsi_Host *shost = transport_class_to_shost(dev);        \
1800        struct iscsi_internal *priv = to_iscsi_internal(shost->transportt); \
1801        return priv->iscsi_transport->get_host_param(shost, param, buf); \
1802}
1803
1804#define iscsi_host_attr(field, param)                                   \
1805        iscsi_host_attr_show(param)                                     \
1806static ISCSI_CLASS_ATTR(host, field, S_IRUGO, show_host_param_##param,  \
1807                        NULL);
1808
1809iscsi_host_attr(netdev, ISCSI_HOST_PARAM_NETDEV_NAME);
1810iscsi_host_attr(hwaddress, ISCSI_HOST_PARAM_HWADDRESS);
1811iscsi_host_attr(ipaddress, ISCSI_HOST_PARAM_IPADDRESS);
1812iscsi_host_attr(initiatorname, ISCSI_HOST_PARAM_INITIATOR_NAME);
1813
1814#define SETUP_PRIV_SESSION_RD_ATTR(field)                               \
1815do {                                                                    \
1816        priv->session_attrs[count] = &dev_attr_priv_sess_##field; \
1817        count++;                                                        \
1818} while (0)
1819
1820
1821#define SETUP_SESSION_RD_ATTR(field, param_flag)                        \
1822do {                                                                    \
1823        if (tt->param_mask & param_flag) {                              \
1824                priv->session_attrs[count] = &dev_attr_sess_##field; \
1825                count++;                                                \
1826        }                                                               \
1827} while (0)
1828
1829#define SETUP_CONN_RD_ATTR(field, param_flag)                           \
1830do {                                                                    \
1831        if (tt->param_mask & param_flag) {                              \
1832                priv->conn_attrs[count] = &dev_attr_conn_##field; \
1833                count++;                                                \
1834        }                                                               \
1835} while (0)
1836
1837#define SETUP_HOST_RD_ATTR(field, param_flag)                           \
1838do {                                                                    \
1839        if (tt->host_param_mask & param_flag) {                         \
1840                priv->host_attrs[count] = &dev_attr_host_##field; \
1841                count++;                                                \
1842        }                                                               \
1843} while (0)
1844
1845static int iscsi_session_match(struct attribute_container *cont,
1846                           struct device *dev)
1847{
1848        struct iscsi_cls_session *session;
1849        struct Scsi_Host *shost;
1850        struct iscsi_internal *priv;
1851
1852        if (!iscsi_is_session_dev(dev))
1853                return 0;
1854
1855        session = iscsi_dev_to_session(dev);
1856        shost = iscsi_session_to_shost(session);
1857        if (!shost->transportt)
1858                return 0;
1859
1860        priv = to_iscsi_internal(shost->transportt);
1861        if (priv->session_cont.ac.class != &iscsi_session_class.class)
1862                return 0;
1863
1864        return &priv->session_cont.ac == cont;
1865}
1866
1867static int iscsi_conn_match(struct attribute_container *cont,
1868                           struct device *dev)
1869{
1870        struct iscsi_cls_session *session;
1871        struct iscsi_cls_conn *conn;
1872        struct Scsi_Host *shost;
1873        struct iscsi_internal *priv;
1874
1875        if (!iscsi_is_conn_dev(dev))
1876                return 0;
1877
1878        conn = iscsi_dev_to_conn(dev);
1879        session = iscsi_dev_to_session(conn->dev.parent);
1880        shost = iscsi_session_to_shost(session);
1881
1882        if (!shost->transportt)
1883                return 0;
1884
1885        priv = to_iscsi_internal(shost->transportt);
1886        if (priv->conn_cont.ac.class != &iscsi_connection_class.class)
1887                return 0;
1888
1889        return &priv->conn_cont.ac == cont;
1890}
1891
1892static int iscsi_host_match(struct attribute_container *cont,
1893                            struct device *dev)
1894{
1895        struct Scsi_Host *shost;
1896        struct iscsi_internal *priv;
1897
1898        if (!scsi_is_host_device(dev))
1899                return 0;
1900
1901        shost = dev_to_shost(dev);
1902        if (!shost->transportt  ||
1903            shost->transportt->host_attrs.ac.class != &iscsi_host_class.class)
1904                return 0;
1905
1906        priv = to_iscsi_internal(shost->transportt);
1907        return &priv->t.host_attrs.ac == cont;
1908}
1909
1910struct scsi_transport_template *
1911iscsi_register_transport(struct iscsi_transport *tt)
1912{
1913        struct iscsi_internal *priv;
1914        unsigned long flags;
1915        int count = 0, err;
1916
1917        BUG_ON(!tt);
1918
1919        priv = iscsi_if_transport_lookup(tt);
1920        if (priv)
1921                return NULL;
1922
1923        priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1924        if (!priv)
1925                return NULL;
1926        INIT_LIST_HEAD(&priv->list);
1927        priv->iscsi_transport = tt;
1928        priv->t.user_scan = iscsi_user_scan;
1929        priv->t.create_work_queue = 1;
1930
1931        priv->dev.class = &iscsi_transport_class;
1932        dev_set_name(&priv->dev, "%s", tt->name);
1933        err = device_register(&priv->dev);
1934        if (err)
1935                goto free_priv;
1936
1937        err = sysfs_create_group(&priv->dev.kobj, &iscsi_transport_group);
1938        if (err)
1939                goto unregister_dev;
1940
1941        /* host parameters */
1942        priv->t.host_attrs.ac.attrs = &priv->host_attrs[0];
1943        priv->t.host_attrs.ac.class = &iscsi_host_class.class;
1944        priv->t.host_attrs.ac.match = iscsi_host_match;
1945        priv->t.host_size = sizeof(struct iscsi_cls_host);
1946        transport_container_register(&priv->t.host_attrs);
1947
1948        SETUP_HOST_RD_ATTR(netdev, ISCSI_HOST_NETDEV_NAME);
1949        SETUP_HOST_RD_ATTR(ipaddress, ISCSI_HOST_IPADDRESS);
1950        SETUP_HOST_RD_ATTR(hwaddress, ISCSI_HOST_HWADDRESS);
1951        SETUP_HOST_RD_ATTR(initiatorname, ISCSI_HOST_INITIATOR_NAME);
1952        BUG_ON(count > ISCSI_HOST_ATTRS);
1953        priv->host_attrs[count] = NULL;
1954        count = 0;
1955
1956        /* connection parameters */
1957        priv->conn_cont.ac.attrs = &priv->conn_attrs[0];
1958        priv->conn_cont.ac.class = &iscsi_connection_class.class;
1959        priv->conn_cont.ac.match = iscsi_conn_match;
1960        transport_container_register(&priv->conn_cont);
1961
1962        SETUP_CONN_RD_ATTR(max_recv_dlength, ISCSI_MAX_RECV_DLENGTH);
1963        SETUP_CONN_RD_ATTR(max_xmit_dlength, ISCSI_MAX_XMIT_DLENGTH);
1964        SETUP_CONN_RD_ATTR(header_digest, ISCSI_HDRDGST_EN);
1965        SETUP_CONN_RD_ATTR(data_digest, ISCSI_DATADGST_EN);
1966        SETUP_CONN_RD_ATTR(ifmarker, ISCSI_IFMARKER_EN);
1967        SETUP_CONN_RD_ATTR(ofmarker, ISCSI_OFMARKER_EN);
1968        SETUP_CONN_RD_ATTR(address, ISCSI_CONN_ADDRESS);
1969        SETUP_CONN_RD_ATTR(port, ISCSI_CONN_PORT);
1970        SETUP_CONN_RD_ATTR(exp_statsn, ISCSI_EXP_STATSN);
1971        SETUP_CONN_RD_ATTR(persistent_address, ISCSI_PERSISTENT_ADDRESS);
1972        SETUP_CONN_RD_ATTR(persistent_port, ISCSI_PERSISTENT_PORT);
1973        SETUP_CONN_RD_ATTR(ping_tmo, ISCSI_PING_TMO);
1974        SETUP_CONN_RD_ATTR(recv_tmo, ISCSI_RECV_TMO);
1975
1976        BUG_ON(count > ISCSI_CONN_ATTRS);
1977        priv->conn_attrs[count] = NULL;
1978        count = 0;
1979
1980        /* session parameters */
1981        priv->session_cont.ac.attrs = &priv->session_attrs[0];
1982        priv->session_cont.ac.class = &iscsi_session_class.class;
1983        priv->session_cont.ac.match = iscsi_session_match;
1984        transport_container_register(&priv->session_cont);
1985
1986        SETUP_SESSION_RD_ATTR(initial_r2t, ISCSI_INITIAL_R2T_EN);
1987        SETUP_SESSION_RD_ATTR(max_outstanding_r2t, ISCSI_MAX_R2T);
1988        SETUP_SESSION_RD_ATTR(immediate_data, ISCSI_IMM_DATA_EN);
1989        SETUP_SESSION_RD_ATTR(first_burst_len, ISCSI_FIRST_BURST);
1990        SETUP_SESSION_RD_ATTR(max_burst_len, ISCSI_MAX_BURST);
1991        SETUP_SESSION_RD_ATTR(data_pdu_in_order, ISCSI_PDU_INORDER_EN);
1992        SETUP_SESSION_RD_ATTR(data_seq_in_order, ISCSI_DATASEQ_INORDER_EN);
1993        SETUP_SESSION_RD_ATTR(erl, ISCSI_ERL);
1994        SETUP_SESSION_RD_ATTR(targetname, ISCSI_TARGET_NAME);
1995        SETUP_SESSION_RD_ATTR(tpgt, ISCSI_TPGT);
1996        SETUP_SESSION_RD_ATTR(password, ISCSI_USERNAME);
1997        SETUP_SESSION_RD_ATTR(password_in, ISCSI_USERNAME_IN);
1998        SETUP_SESSION_RD_ATTR(username, ISCSI_PASSWORD);
1999        SETUP_SESSION_RD_ATTR(username_in, ISCSI_PASSWORD_IN);
2000        SETUP_SESSION_RD_ATTR(fast_abort, ISCSI_FAST_ABORT);
2001        SETUP_SESSION_RD_ATTR(abort_tmo, ISCSI_ABORT_TMO);
2002        SETUP_SESSION_RD_ATTR(lu_reset_tmo,ISCSI_LU_RESET_TMO);
2003        SETUP_SESSION_RD_ATTR(ifacename, ISCSI_IFACE_NAME);
2004        SETUP_SESSION_RD_ATTR(initiatorname, ISCSI_INITIATOR_NAME);
2005        SETUP_PRIV_SESSION_RD_ATTR(recovery_tmo);
2006        SETUP_PRIV_SESSION_RD_ATTR(state);
2007
2008        BUG_ON(count > ISCSI_SESSION_ATTRS);
2009        priv->session_attrs[count] = NULL;
2010
2011        spin_lock_irqsave(&iscsi_transport_lock, flags);
2012        list_add(&priv->list, &iscsi_transports);
2013        spin_unlock_irqrestore(&iscsi_transport_lock, flags);
2014
2015        printk(KERN_NOTICE "iscsi: registered transport (%s)\n", tt->name);
2016        return &priv->t;
2017
2018unregister_dev:
2019        device_unregister(&priv->dev);
2020        return NULL;
2021free_priv:
2022        kfree(priv);
2023        return NULL;
2024}
2025EXPORT_SYMBOL_GPL(iscsi_register_transport);
2026
2027int iscsi_unregister_transport(struct iscsi_transport *tt)
2028{
2029        struct iscsi_internal *priv;
2030        unsigned long flags;
2031
2032        BUG_ON(!tt);
2033
2034        mutex_lock(&rx_queue_mutex);
2035
2036        priv = iscsi_if_transport_lookup(tt);
2037        BUG_ON (!priv);
2038
2039        spin_lock_irqsave(&iscsi_transport_lock, flags);
2040        list_del(&priv->list);
2041        spin_unlock_irqrestore(&iscsi_transport_lock, flags);
2042
2043        transport_container_unregister(&priv->conn_cont);
2044        transport_container_unregister(&priv->session_cont);
2045        transport_container_unregister(&priv->t.host_attrs);
2046
2047        sysfs_remove_group(&priv->dev.kobj, &iscsi_transport_group);
2048        device_unregister(&priv->dev);
2049        mutex_unlock(&rx_queue_mutex);
2050
2051        return 0;
2052}
2053EXPORT_SYMBOL_GPL(iscsi_unregister_transport);
2054
2055static __init int iscsi_transport_init(void)
2056{
2057        int err;
2058
2059        printk(KERN_INFO "Loading iSCSI transport class v%s.\n",
2060                ISCSI_TRANSPORT_VERSION);
2061
2062        atomic_set(&iscsi_session_nr, 0);
2063
2064        err = class_register(&iscsi_transport_class);
2065        if (err)
2066                return err;
2067
2068        err = class_register(&iscsi_endpoint_class);
2069        if (err)
2070                goto unregister_transport_class;
2071
2072        err = transport_class_register(&iscsi_host_class);
2073        if (err)
2074                goto unregister_endpoint_class;
2075
2076        err = transport_class_register(&iscsi_connection_class);
2077        if (err)
2078                goto unregister_host_class;
2079
2080        err = transport_class_register(&iscsi_session_class);
2081        if (err)
2082                goto unregister_conn_class;
2083
2084        nls = netlink_kernel_create(&init_net, NETLINK_ISCSI, 1, iscsi_if_rx,
2085                                    NULL, THIS_MODULE);
2086        if (!nls) {
2087                err = -ENOBUFS;
2088                goto unregister_session_class;
2089        }
2090
2091        iscsi_eh_timer_workq = create_singlethread_workqueue("iscsi_eh");
2092        if (!iscsi_eh_timer_workq)
2093                goto release_nls;
2094
2095        return 0;
2096
2097release_nls:
2098        netlink_kernel_release(nls);
2099unregister_session_class:
2100        transport_class_unregister(&iscsi_session_class);
2101unregister_conn_class:
2102        transport_class_unregister(&iscsi_connection_class);
2103unregister_host_class:
2104        transport_class_unregister(&iscsi_host_class);
2105unregister_endpoint_class:
2106        class_unregister(&iscsi_endpoint_class);
2107unregister_transport_class:
2108        class_unregister(&iscsi_transport_class);
2109        return err;
2110}
2111
2112static void __exit iscsi_transport_exit(void)
2113{
2114        destroy_workqueue(iscsi_eh_timer_workq);
2115        netlink_kernel_release(nls);
2116        transport_class_unregister(&iscsi_connection_class);
2117        transport_class_unregister(&iscsi_session_class);
2118        transport_class_unregister(&iscsi_host_class);
2119        class_unregister(&iscsi_endpoint_class);
2120        class_unregister(&iscsi_transport_class);
2121}
2122
2123module_init(iscsi_transport_init);
2124module_exit(iscsi_transport_exit);
2125
2126MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
2127              "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
2128              "Alex Aizman <itn780@yahoo.com>");
2129MODULE_DESCRIPTION("iSCSI Transport Interface");
2130MODULE_LICENSE("GPL");
2131MODULE_VERSION(ISCSI_TRANSPORT_VERSION);
2132