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 <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
  34#define ISCSI_SESSION_ATTRS 22
  35#define ISCSI_CONN_ATTRS 13
  36#define ISCSI_HOST_ATTRS 4
  37
  38#define ISCSI_TRANSPORT_VERSION "2.0-870"
  39
  40static int dbg_session;
  41module_param_named(debug_session, dbg_session, int,
  42                   S_IRUGO | S_IWUSR);
  43MODULE_PARM_DESC(debug_session,
  44                 "Turn on debugging for sessions in scsi_transport_iscsi "
  45                 "module. Set to 1 to turn on, and zero to turn off. Default "
  46                 "is off.");
  47
  48static int dbg_conn;
  49module_param_named(debug_conn, dbg_conn, int,
  50                   S_IRUGO | S_IWUSR);
  51MODULE_PARM_DESC(debug_conn,
  52                 "Turn on debugging for connections in scsi_transport_iscsi "
  53                 "module. Set to 1 to turn on, and zero to turn off. Default "
  54                 "is off.");
  55
  56#define ISCSI_DBG_TRANS_SESSION(_session, dbg_fmt, arg...)              \
  57        do {                                                            \
  58                if (dbg_session)                                        \
  59                        iscsi_cls_session_printk(KERN_INFO, _session,   \
  60                                                 "%s: " dbg_fmt,        \
  61                                                 __func__, ##arg);      \
  62        } while (0);
  63
  64#define ISCSI_DBG_TRANS_CONN(_conn, dbg_fmt, arg...)                    \
  65        do {                                                            \
  66                if (dbg_conn)                                           \
  67                        iscsi_cls_conn_printk(KERN_INFO, _conn,         \
  68                                              "%s: " dbg_fmt,           \
  69                                              __func__, ##arg); \
  70        } while (0);
  71
  72struct iscsi_internal {
  73        struct scsi_transport_template t;
  74        struct iscsi_transport *iscsi_transport;
  75        struct list_head list;
  76        struct device dev;
  77
  78        struct device_attribute *host_attrs[ISCSI_HOST_ATTRS + 1];
  79        struct transport_container conn_cont;
  80        struct device_attribute *conn_attrs[ISCSI_CONN_ATTRS + 1];
  81        struct transport_container session_cont;
  82        struct device_attribute *session_attrs[ISCSI_SESSION_ATTRS + 1];
  83};
  84
  85static atomic_t iscsi_session_nr; /* sysfs session id for next new session */
  86static struct workqueue_struct *iscsi_eh_timer_workq;
  87
  88/*
  89 * list of registered transports and lock that must
  90 * be held while accessing list. The iscsi_transport_lock must
  91 * be acquired after the rx_queue_mutex.
  92 */
  93static LIST_HEAD(iscsi_transports);
  94static DEFINE_SPINLOCK(iscsi_transport_lock);
  95
  96#define to_iscsi_internal(tmpl) \
  97        container_of(tmpl, struct iscsi_internal, t)
  98
  99#define dev_to_iscsi_internal(_dev) \
 100        container_of(_dev, struct iscsi_internal, dev)
 101
 102static void iscsi_transport_release(struct device *dev)
 103{
 104        struct iscsi_internal *priv = dev_to_iscsi_internal(dev);
 105        kfree(priv);
 106}
 107
 108/*
 109 * iscsi_transport_class represents the iscsi_transports that are
 110 * registered.
 111 */
 112static struct class iscsi_transport_class = {
 113        .name = "iscsi_transport",
 114        .dev_release = iscsi_transport_release,
 115};
 116
 117static ssize_t
 118show_transport_handle(struct device *dev, struct device_attribute *attr,
 119                      char *buf)
 120{
 121        struct iscsi_internal *priv = dev_to_iscsi_internal(dev);
 122        return sprintf(buf, "%llu\n", (unsigned long long)iscsi_handle(priv->iscsi_transport));
 123}
 124static DEVICE_ATTR(handle, S_IRUGO, show_transport_handle, NULL);
 125
 126#define show_transport_attr(name, format)                               \
 127static ssize_t                                                          \
 128show_transport_##name(struct device *dev,                               \
 129                      struct device_attribute *attr,char *buf)          \
 130{                                                                       \
 131        struct iscsi_internal *priv = dev_to_iscsi_internal(dev);       \
 132        return sprintf(buf, format"\n", priv->iscsi_transport->name);   \
 133}                                                                       \
 134static DEVICE_ATTR(name, S_IRUGO, show_transport_##name, NULL);
 135
 136show_transport_attr(caps, "0x%x");
 137
 138static struct attribute *iscsi_transport_attrs[] = {
 139        &dev_attr_handle.attr,
 140        &dev_attr_caps.attr,
 141        NULL,
 142};
 143
 144static struct attribute_group iscsi_transport_group = {
 145        .attrs = iscsi_transport_attrs,
 146};
 147
 148/*
 149 * iSCSI endpoint attrs
 150 */
 151#define iscsi_dev_to_endpoint(_dev) \
 152        container_of(_dev, struct iscsi_endpoint, dev)
 153
 154#define ISCSI_ATTR(_prefix,_name,_mode,_show,_store)    \
 155struct device_attribute dev_attr_##_prefix##_##_name =  \
 156        __ATTR(_name,_mode,_show,_store)
 157
 158static void iscsi_endpoint_release(struct device *dev)
 159{
 160        struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
 161        kfree(ep);
 162}
 163
 164static struct class iscsi_endpoint_class = {
 165        .name = "iscsi_endpoint",
 166        .dev_release = iscsi_endpoint_release,
 167};
 168
 169static ssize_t
 170show_ep_handle(struct device *dev, struct device_attribute *attr, char *buf)
 171{
 172        struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
 173        return sprintf(buf, "%llu\n", (unsigned long long) ep->id);
 174}
 175static ISCSI_ATTR(ep, handle, S_IRUGO, show_ep_handle, NULL);
 176
 177static struct attribute *iscsi_endpoint_attrs[] = {
 178        &dev_attr_ep_handle.attr,
 179        NULL,
 180};
 181
 182static struct attribute_group iscsi_endpoint_group = {
 183        .attrs = iscsi_endpoint_attrs,
 184};
 185
 186#define ISCSI_MAX_EPID -1
 187
 188static int iscsi_match_epid(struct device *dev, void *data)
 189{
 190        struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
 191        uint64_t *epid = (uint64_t *) data;
 192
 193        return *epid == ep->id;
 194}
 195
 196struct iscsi_endpoint *
 197iscsi_create_endpoint(int dd_size)
 198{
 199        struct device *dev;
 200        struct iscsi_endpoint *ep;
 201        uint64_t id;
 202        int err;
 203
 204        for (id = 1; id < ISCSI_MAX_EPID; id++) {
 205                dev = class_find_device(&iscsi_endpoint_class, NULL, &id,
 206                                        iscsi_match_epid);
 207                if (!dev)
 208                        break;
 209        }
 210        if (id == ISCSI_MAX_EPID) {
 211                printk(KERN_ERR "Too many connections. Max supported %u\n",
 212                       ISCSI_MAX_EPID - 1);
 213                return NULL;
 214        }
 215
 216        ep = kzalloc(sizeof(*ep) + dd_size, GFP_KERNEL);
 217        if (!ep)
 218                return NULL;
 219
 220        ep->id = id;
 221        ep->dev.class = &iscsi_endpoint_class;
 222        dev_set_name(&ep->dev, "ep-%llu", (unsigned long long) id);
 223        err = device_register(&ep->dev);
 224        if (err)
 225                goto free_ep;
 226
 227        err = sysfs_create_group(&ep->dev.kobj, &iscsi_endpoint_group);
 228        if (err)
 229                goto unregister_dev;
 230
 231        if (dd_size)
 232                ep->dd_data = &ep[1];
 233        return ep;
 234
 235unregister_dev:
 236        device_unregister(&ep->dev);
 237        return NULL;
 238
 239free_ep:
 240        kfree(ep);
 241        return NULL;
 242}
 243EXPORT_SYMBOL_GPL(iscsi_create_endpoint);
 244
 245void iscsi_destroy_endpoint(struct iscsi_endpoint *ep)
 246{
 247        sysfs_remove_group(&ep->dev.kobj, &iscsi_endpoint_group);
 248        device_unregister(&ep->dev);
 249}
 250EXPORT_SYMBOL_GPL(iscsi_destroy_endpoint);
 251
 252struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle)
 253{
 254        struct iscsi_endpoint *ep;
 255        struct device *dev;
 256
 257        dev = class_find_device(&iscsi_endpoint_class, NULL, &handle,
 258                                iscsi_match_epid);
 259        if (!dev)
 260                return NULL;
 261
 262        ep = iscsi_dev_to_endpoint(dev);
 263        /*
 264         * we can drop this now because the interface will prevent
 265         * removals and lookups from racing.
 266         */
 267        put_device(dev);
 268        return ep;
 269}
 270EXPORT_SYMBOL_GPL(iscsi_lookup_endpoint);
 271
 272static int iscsi_setup_host(struct transport_container *tc, struct device *dev,
 273                            struct device *cdev)
 274{
 275        struct Scsi_Host *shost = dev_to_shost(dev);
 276        struct iscsi_cls_host *ihost = shost->shost_data;
 277
 278        memset(ihost, 0, sizeof(*ihost));
 279        atomic_set(&ihost->nr_scans, 0);
 280        mutex_init(&ihost->mutex);
 281        return 0;
 282}
 283
 284static DECLARE_TRANSPORT_CLASS(iscsi_host_class,
 285                               "iscsi_host",
 286                               iscsi_setup_host,
 287                               NULL,
 288                               NULL);
 289
 290static DECLARE_TRANSPORT_CLASS(iscsi_session_class,
 291                               "iscsi_session",
 292                               NULL,
 293                               NULL,
 294                               NULL);
 295
 296static DECLARE_TRANSPORT_CLASS(iscsi_connection_class,
 297                               "iscsi_connection",
 298                               NULL,
 299                               NULL,
 300                               NULL);
 301
 302static struct sock *nls;
 303static DEFINE_MUTEX(rx_queue_mutex);
 304
 305static LIST_HEAD(sesslist);
 306static DEFINE_SPINLOCK(sesslock);
 307static LIST_HEAD(connlist);
 308static DEFINE_SPINLOCK(connlock);
 309
 310static uint32_t iscsi_conn_get_sid(struct iscsi_cls_conn *conn)
 311{
 312        struct iscsi_cls_session *sess = iscsi_dev_to_session(conn->dev.parent);
 313        return sess->sid;
 314}
 315
 316/*
 317 * Returns the matching session to a given sid
 318 */
 319static struct iscsi_cls_session *iscsi_session_lookup(uint32_t sid)
 320{
 321        unsigned long flags;
 322        struct iscsi_cls_session *sess;
 323
 324        spin_lock_irqsave(&sesslock, flags);
 325        list_for_each_entry(sess, &sesslist, sess_list) {
 326                if (sess->sid == sid) {
 327                        spin_unlock_irqrestore(&sesslock, flags);
 328                        return sess;
 329                }
 330        }
 331        spin_unlock_irqrestore(&sesslock, flags);
 332        return NULL;
 333}
 334
 335/*
 336 * Returns the matching connection to a given sid / cid tuple
 337 */
 338static struct iscsi_cls_conn *iscsi_conn_lookup(uint32_t sid, uint32_t cid)
 339{
 340        unsigned long flags;
 341        struct iscsi_cls_conn *conn;
 342
 343        spin_lock_irqsave(&connlock, flags);
 344        list_for_each_entry(conn, &connlist, conn_list) {
 345                if ((conn->cid == cid) && (iscsi_conn_get_sid(conn) == sid)) {
 346                        spin_unlock_irqrestore(&connlock, flags);
 347                        return conn;
 348                }
 349        }
 350        spin_unlock_irqrestore(&connlock, flags);
 351        return NULL;
 352}
 353
 354/*
 355 * The following functions can be used by LLDs that allocate
 356 * their own scsi_hosts or by software iscsi LLDs
 357 */
 358static struct {
 359        int value;
 360        char *name;
 361} iscsi_session_state_names[] = {
 362        { ISCSI_SESSION_LOGGED_IN,      "LOGGED_IN" },
 363        { ISCSI_SESSION_FAILED,         "FAILED" },
 364        { ISCSI_SESSION_FREE,           "FREE" },
 365};
 366
 367static const char *iscsi_session_state_name(int state)
 368{
 369        int i;
 370        char *name = NULL;
 371
 372        for (i = 0; i < ARRAY_SIZE(iscsi_session_state_names); i++) {
 373                if (iscsi_session_state_names[i].value == state) {
 374                        name = iscsi_session_state_names[i].name;
 375                        break;
 376                }
 377        }
 378        return name;
 379}
 380
 381int iscsi_session_chkready(struct iscsi_cls_session *session)
 382{
 383        unsigned long flags;
 384        int err;
 385
 386        spin_lock_irqsave(&session->lock, flags);
 387        switch (session->state) {
 388        case ISCSI_SESSION_LOGGED_IN:
 389                err = 0;
 390                break;
 391        case ISCSI_SESSION_FAILED:
 392                err = DID_IMM_RETRY << 16;
 393                break;
 394        case ISCSI_SESSION_FREE:
 395                err = DID_TRANSPORT_FAILFAST << 16;
 396                break;
 397        default:
 398                err = DID_NO_CONNECT << 16;
 399                break;
 400        }
 401        spin_unlock_irqrestore(&session->lock, flags);
 402        return err;
 403}
 404EXPORT_SYMBOL_GPL(iscsi_session_chkready);
 405
 406static void iscsi_session_release(struct device *dev)
 407{
 408        struct iscsi_cls_session *session = iscsi_dev_to_session(dev);
 409        struct Scsi_Host *shost;
 410
 411        shost = iscsi_session_to_shost(session);
 412        scsi_host_put(shost);
 413        ISCSI_DBG_TRANS_SESSION(session, "Completing session release\n");
 414        kfree(session);
 415}
 416
 417static int iscsi_is_session_dev(const struct device *dev)
 418{
 419        return dev->release == iscsi_session_release;
 420}
 421
 422static int iscsi_iter_session_fn(struct device *dev, void *data)
 423{
 424        void (* fn) (struct iscsi_cls_session *) = data;
 425
 426        if (!iscsi_is_session_dev(dev))
 427                return 0;
 428        fn(iscsi_dev_to_session(dev));
 429        return 0;
 430}
 431
 432void iscsi_host_for_each_session(struct Scsi_Host *shost,
 433                                 void (*fn)(struct iscsi_cls_session *))
 434{
 435        device_for_each_child(&shost->shost_gendev, fn,
 436                              iscsi_iter_session_fn);
 437}
 438EXPORT_SYMBOL_GPL(iscsi_host_for_each_session);
 439
 440/**
 441 * iscsi_scan_finished - helper to report when running scans are done
 442 * @shost: scsi host
 443 * @time: scan run time
 444 *
 445 * This function can be used by drives like qla4xxx to report to the scsi
 446 * layer when the scans it kicked off at module load time are done.
 447 */
 448int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time)
 449{
 450        struct iscsi_cls_host *ihost = shost->shost_data;
 451        /*
 452         * qla4xxx will have kicked off some session unblocks before calling
 453         * scsi_scan_host, so just wait for them to complete.
 454         */
 455        return !atomic_read(&ihost->nr_scans);
 456}
 457EXPORT_SYMBOL_GPL(iscsi_scan_finished);
 458
 459struct iscsi_scan_data {
 460        unsigned int channel;
 461        unsigned int id;
 462        unsigned int lun;
 463};
 464
 465static int iscsi_user_scan_session(struct device *dev, void *data)
 466{
 467        struct iscsi_scan_data *scan_data = data;
 468        struct iscsi_cls_session *session;
 469        struct Scsi_Host *shost;
 470        struct iscsi_cls_host *ihost;
 471        unsigned long flags;
 472        unsigned int id;
 473
 474        if (!iscsi_is_session_dev(dev))
 475                return 0;
 476
 477        session = iscsi_dev_to_session(dev);
 478
 479        ISCSI_DBG_TRANS_SESSION(session, "Scanning session\n");
 480
 481        shost = iscsi_session_to_shost(session);
 482        ihost = shost->shost_data;
 483
 484        mutex_lock(&ihost->mutex);
 485        spin_lock_irqsave(&session->lock, flags);
 486        if (session->state != ISCSI_SESSION_LOGGED_IN) {
 487                spin_unlock_irqrestore(&session->lock, flags);
 488                goto user_scan_exit;
 489        }
 490        id = session->target_id;
 491        spin_unlock_irqrestore(&session->lock, flags);
 492
 493        if (id != ISCSI_MAX_TARGET) {
 494                if ((scan_data->channel == SCAN_WILD_CARD ||
 495                     scan_data->channel == 0) &&
 496                    (scan_data->id == SCAN_WILD_CARD ||
 497                     scan_data->id == id))
 498                        scsi_scan_target(&session->dev, 0, id,
 499                                         scan_data->lun, 1);
 500        }
 501
 502user_scan_exit:
 503        mutex_unlock(&ihost->mutex);
 504        ISCSI_DBG_TRANS_SESSION(session, "Completed session scan\n");
 505        return 0;
 506}
 507
 508static int iscsi_user_scan(struct Scsi_Host *shost, uint channel,
 509                           uint id, uint lun)
 510{
 511        struct iscsi_scan_data scan_data;
 512
 513        scan_data.channel = channel;
 514        scan_data.id = id;
 515        scan_data.lun = lun;
 516
 517        return device_for_each_child(&shost->shost_gendev, &scan_data,
 518                                     iscsi_user_scan_session);
 519}
 520
 521static void iscsi_scan_session(struct work_struct *work)
 522{
 523        struct iscsi_cls_session *session =
 524                        container_of(work, struct iscsi_cls_session, scan_work);
 525        struct Scsi_Host *shost = iscsi_session_to_shost(session);
 526        struct iscsi_cls_host *ihost = shost->shost_data;
 527        struct iscsi_scan_data scan_data;
 528
 529        scan_data.channel = 0;
 530        scan_data.id = SCAN_WILD_CARD;
 531        scan_data.lun = SCAN_WILD_CARD;
 532
 533        iscsi_user_scan_session(&session->dev, &scan_data);
 534        atomic_dec(&ihost->nr_scans);
 535}
 536
 537static void session_recovery_timedout(struct work_struct *work)
 538{
 539        struct iscsi_cls_session *session =
 540                container_of(work, struct iscsi_cls_session,
 541                             recovery_work.work);
 542        unsigned long flags;
 543
 544        iscsi_cls_session_printk(KERN_INFO, session,
 545                                 "session recovery timed out after %d secs\n",
 546                                 session->recovery_tmo);
 547
 548        spin_lock_irqsave(&session->lock, flags);
 549        switch (session->state) {
 550        case ISCSI_SESSION_FAILED:
 551                session->state = ISCSI_SESSION_FREE;
 552                break;
 553        case ISCSI_SESSION_LOGGED_IN:
 554        case ISCSI_SESSION_FREE:
 555                /* we raced with the unblock's flush */
 556                spin_unlock_irqrestore(&session->lock, flags);
 557                return;
 558        }
 559        spin_unlock_irqrestore(&session->lock, flags);
 560
 561        if (session->transport->session_recovery_timedout)
 562                session->transport->session_recovery_timedout(session);
 563
 564        ISCSI_DBG_TRANS_SESSION(session, "Unblocking SCSI target\n");
 565        scsi_target_unblock(&session->dev);
 566        ISCSI_DBG_TRANS_SESSION(session, "Completed unblocking SCSI target\n");
 567}
 568
 569static void __iscsi_unblock_session(struct work_struct *work)
 570{
 571        struct iscsi_cls_session *session =
 572                        container_of(work, struct iscsi_cls_session,
 573                                     unblock_work);
 574        struct Scsi_Host *shost = iscsi_session_to_shost(session);
 575        struct iscsi_cls_host *ihost = shost->shost_data;
 576        unsigned long flags;
 577
 578        ISCSI_DBG_TRANS_SESSION(session, "Unblocking session\n");
 579        /*
 580         * The recovery and unblock work get run from the same workqueue,
 581         * so try to cancel it if it was going to run after this unblock.
 582         */
 583        cancel_delayed_work(&session->recovery_work);
 584        spin_lock_irqsave(&session->lock, flags);
 585        session->state = ISCSI_SESSION_LOGGED_IN;
 586        spin_unlock_irqrestore(&session->lock, flags);
 587        /* start IO */
 588        scsi_target_unblock(&session->dev);
 589        /*
 590         * Only do kernel scanning if the driver is properly hooked into
 591         * the async scanning code (drivers like iscsi_tcp do login and
 592         * scanning from userspace).
 593         */
 594        if (shost->hostt->scan_finished) {
 595                if (scsi_queue_work(shost, &session->scan_work))
 596                        atomic_inc(&ihost->nr_scans);
 597        }
 598        ISCSI_DBG_TRANS_SESSION(session, "Completed unblocking session\n");
 599}
 600
 601/**
 602 * iscsi_unblock_session - set a session as logged in and start IO.
 603 * @session: iscsi session
 604 *
 605 * Mark a session as ready to accept IO.
 606 */
 607void iscsi_unblock_session(struct iscsi_cls_session *session)
 608{
 609        queue_work(iscsi_eh_timer_workq, &session->unblock_work);
 610        /*
 611         * make sure all the events have completed before tell the driver
 612         * it is safe
 613         */
 614        flush_workqueue(iscsi_eh_timer_workq);
 615}
 616EXPORT_SYMBOL_GPL(iscsi_unblock_session);
 617
 618static void __iscsi_block_session(struct work_struct *work)
 619{
 620        struct iscsi_cls_session *session =
 621                        container_of(work, struct iscsi_cls_session,
 622                                     block_work);
 623        unsigned long flags;
 624
 625        ISCSI_DBG_TRANS_SESSION(session, "Blocking session\n");
 626        spin_lock_irqsave(&session->lock, flags);
 627        session->state = ISCSI_SESSION_FAILED;
 628        spin_unlock_irqrestore(&session->lock, flags);
 629        scsi_target_block(&session->dev);
 630        ISCSI_DBG_TRANS_SESSION(session, "Completed SCSI target blocking\n");
 631        if (session->recovery_tmo >= 0)
 632                queue_delayed_work(iscsi_eh_timer_workq,
 633                                   &session->recovery_work,
 634                                   session->recovery_tmo * HZ);
 635}
 636
 637void iscsi_block_session(struct iscsi_cls_session *session)
 638{
 639        queue_work(iscsi_eh_timer_workq, &session->block_work);
 640}
 641EXPORT_SYMBOL_GPL(iscsi_block_session);
 642
 643static void __iscsi_unbind_session(struct work_struct *work)
 644{
 645        struct iscsi_cls_session *session =
 646                        container_of(work, struct iscsi_cls_session,
 647                                     unbind_work);
 648        struct Scsi_Host *shost = iscsi_session_to_shost(session);
 649        struct iscsi_cls_host *ihost = shost->shost_data;
 650        unsigned long flags;
 651
 652        ISCSI_DBG_TRANS_SESSION(session, "Unbinding session\n");
 653
 654        /* Prevent new scans and make sure scanning is not in progress */
 655        mutex_lock(&ihost->mutex);
 656        spin_lock_irqsave(&session->lock, flags);
 657        if (session->target_id == ISCSI_MAX_TARGET) {
 658                spin_unlock_irqrestore(&session->lock, flags);
 659                mutex_unlock(&ihost->mutex);
 660                return;
 661        }
 662        session->target_id = ISCSI_MAX_TARGET;
 663        spin_unlock_irqrestore(&session->lock, flags);
 664        mutex_unlock(&ihost->mutex);
 665
 666        scsi_remove_target(&session->dev);
 667        iscsi_session_event(session, ISCSI_KEVENT_UNBIND_SESSION);
 668        ISCSI_DBG_TRANS_SESSION(session, "Completed target removal\n");
 669}
 670
 671struct iscsi_cls_session *
 672iscsi_alloc_session(struct Scsi_Host *shost, struct iscsi_transport *transport,
 673                    int dd_size)
 674{
 675        struct iscsi_cls_session *session;
 676
 677        session = kzalloc(sizeof(*session) + dd_size,
 678                          GFP_KERNEL);
 679        if (!session)
 680                return NULL;
 681
 682        session->transport = transport;
 683        session->recovery_tmo = 120;
 684        session->state = ISCSI_SESSION_FREE;
 685        INIT_DELAYED_WORK(&session->recovery_work, session_recovery_timedout);
 686        INIT_LIST_HEAD(&session->sess_list);
 687        INIT_WORK(&session->unblock_work, __iscsi_unblock_session);
 688        INIT_WORK(&session->block_work, __iscsi_block_session);
 689        INIT_WORK(&session->unbind_work, __iscsi_unbind_session);
 690        INIT_WORK(&session->scan_work, iscsi_scan_session);
 691        spin_lock_init(&session->lock);
 692
 693        /* this is released in the dev's release function */
 694        scsi_host_get(shost);
 695        session->dev.parent = &shost->shost_gendev;
 696        session->dev.release = iscsi_session_release;
 697        device_initialize(&session->dev);
 698        if (dd_size)
 699                session->dd_data = &session[1];
 700
 701        ISCSI_DBG_TRANS_SESSION(session, "Completed session allocation\n");
 702        return session;
 703}
 704EXPORT_SYMBOL_GPL(iscsi_alloc_session);
 705
 706static int iscsi_get_next_target_id(struct device *dev, void *data)
 707{
 708        struct iscsi_cls_session *session;
 709        unsigned long flags;
 710        int err = 0;
 711
 712        if (!iscsi_is_session_dev(dev))
 713                return 0;
 714
 715        session = iscsi_dev_to_session(dev);
 716        spin_lock_irqsave(&session->lock, flags);
 717        if (*((unsigned int *) data) == session->target_id)
 718                err = -EEXIST;
 719        spin_unlock_irqrestore(&session->lock, flags);
 720        return err;
 721}
 722
 723int iscsi_add_session(struct iscsi_cls_session *session, unsigned int target_id)
 724{
 725        struct Scsi_Host *shost = iscsi_session_to_shost(session);
 726        struct iscsi_cls_host *ihost;
 727        unsigned long flags;
 728        unsigned int id = target_id;
 729        int err;
 730
 731        ihost = shost->shost_data;
 732        session->sid = atomic_add_return(1, &iscsi_session_nr);
 733
 734        if (id == ISCSI_MAX_TARGET) {
 735                for (id = 0; id < ISCSI_MAX_TARGET; id++) {
 736                        err = device_for_each_child(&shost->shost_gendev, &id,
 737                                                    iscsi_get_next_target_id);
 738                        if (!err)
 739                                break;
 740                }
 741
 742                if (id == ISCSI_MAX_TARGET) {
 743                        iscsi_cls_session_printk(KERN_ERR, session,
 744                                                 "Too many iscsi targets. Max "
 745                                                 "number of targets is %d.\n",
 746                                                 ISCSI_MAX_TARGET - 1);
 747                        err = -EOVERFLOW;
 748                        goto release_host;
 749                }
 750        }
 751        session->target_id = id;
 752
 753        dev_set_name(&session->dev, "session%u", session->sid);
 754        err = device_add(&session->dev);
 755        if (err) {
 756                iscsi_cls_session_printk(KERN_ERR, session,
 757                                         "could not register session's dev\n");
 758                goto release_host;
 759        }
 760        transport_register_device(&session->dev);
 761
 762        spin_lock_irqsave(&sesslock, flags);
 763        list_add(&session->sess_list, &sesslist);
 764        spin_unlock_irqrestore(&sesslock, flags);
 765
 766        iscsi_session_event(session, ISCSI_KEVENT_CREATE_SESSION);
 767        ISCSI_DBG_TRANS_SESSION(session, "Completed session adding\n");
 768        return 0;
 769
 770release_host:
 771        scsi_host_put(shost);
 772        return err;
 773}
 774EXPORT_SYMBOL_GPL(iscsi_add_session);
 775
 776/**
 777 * iscsi_create_session - create iscsi class session
 778 * @shost: scsi host
 779 * @transport: iscsi transport
 780 * @dd_size: private driver data size
 781 * @target_id: which target
 782 *
 783 * This can be called from a LLD or iscsi_transport.
 784 */
 785struct iscsi_cls_session *
 786iscsi_create_session(struct Scsi_Host *shost, struct iscsi_transport *transport,
 787                     int dd_size, unsigned int target_id)
 788{
 789        struct iscsi_cls_session *session;
 790
 791        session = iscsi_alloc_session(shost, transport, dd_size);
 792        if (!session)
 793                return NULL;
 794
 795        if (iscsi_add_session(session, target_id)) {
 796                iscsi_free_session(session);
 797                return NULL;
 798        }
 799        return session;
 800}
 801EXPORT_SYMBOL_GPL(iscsi_create_session);
 802
 803static void iscsi_conn_release(struct device *dev)
 804{
 805        struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev);
 806        struct device *parent = conn->dev.parent;
 807
 808        ISCSI_DBG_TRANS_CONN(conn, "Releasing conn\n");
 809        kfree(conn);
 810        put_device(parent);
 811}
 812
 813static int iscsi_is_conn_dev(const struct device *dev)
 814{
 815        return dev->release == iscsi_conn_release;
 816}
 817
 818static int iscsi_iter_destroy_conn_fn(struct device *dev, void *data)
 819{
 820        if (!iscsi_is_conn_dev(dev))
 821                return 0;
 822        return iscsi_destroy_conn(iscsi_dev_to_conn(dev));
 823}
 824
 825void iscsi_remove_session(struct iscsi_cls_session *session)
 826{
 827        struct Scsi_Host *shost = iscsi_session_to_shost(session);
 828        unsigned long flags;
 829        int err;
 830
 831        ISCSI_DBG_TRANS_SESSION(session, "Removing session\n");
 832
 833        spin_lock_irqsave(&sesslock, flags);
 834        list_del(&session->sess_list);
 835        spin_unlock_irqrestore(&sesslock, flags);
 836
 837        /* make sure there are no blocks/unblocks queued */
 838        flush_workqueue(iscsi_eh_timer_workq);
 839        /* make sure the timedout callout is not running */
 840        if (!cancel_delayed_work(&session->recovery_work))
 841                flush_workqueue(iscsi_eh_timer_workq);
 842        /*
 843         * If we are blocked let commands flow again. The lld or iscsi
 844         * layer should set up the queuecommand to fail commands.
 845         * We assume that LLD will not be calling block/unblock while
 846         * removing the session.
 847         */
 848        spin_lock_irqsave(&session->lock, flags);
 849        session->state = ISCSI_SESSION_FREE;
 850        spin_unlock_irqrestore(&session->lock, flags);
 851
 852        scsi_target_unblock(&session->dev);
 853        /* flush running scans then delete devices */
 854        scsi_flush_work(shost);
 855        __iscsi_unbind_session(&session->unbind_work);
 856
 857        /* hw iscsi may not have removed all connections from session */
 858        err = device_for_each_child(&session->dev, NULL,
 859                                    iscsi_iter_destroy_conn_fn);
 860        if (err)
 861                iscsi_cls_session_printk(KERN_ERR, session,
 862                                         "Could not delete all connections "
 863                                         "for session. Error %d.\n", err);
 864
 865        transport_unregister_device(&session->dev);
 866
 867        ISCSI_DBG_TRANS_SESSION(session, "Completing session removal\n");
 868        device_del(&session->dev);
 869}
 870EXPORT_SYMBOL_GPL(iscsi_remove_session);
 871
 872void iscsi_free_session(struct iscsi_cls_session *session)
 873{
 874        ISCSI_DBG_TRANS_SESSION(session, "Freeing session\n");
 875        iscsi_session_event(session, ISCSI_KEVENT_DESTROY_SESSION);
 876        put_device(&session->dev);
 877}
 878EXPORT_SYMBOL_GPL(iscsi_free_session);
 879
 880/**
 881 * iscsi_destroy_session - destroy iscsi session
 882 * @session: iscsi_session
 883 *
 884 * Can be called by a LLD or iscsi_transport. There must not be
 885 * any running connections.
 886 */
 887int iscsi_destroy_session(struct iscsi_cls_session *session)
 888{
 889        iscsi_remove_session(session);
 890        ISCSI_DBG_TRANS_SESSION(session, "Completing session destruction\n");
 891        iscsi_free_session(session);
 892        return 0;
 893}
 894EXPORT_SYMBOL_GPL(iscsi_destroy_session);
 895
 896/**
 897 * iscsi_create_conn - create iscsi class connection
 898 * @session: iscsi cls session
 899 * @dd_size: private driver data size
 900 * @cid: connection id
 901 *
 902 * This can be called from a LLD or iscsi_transport. The connection
 903 * is child of the session so cid must be unique for all connections
 904 * on the session.
 905 *
 906 * Since we do not support MCS, cid will normally be zero. In some cases
 907 * for software iscsi we could be trying to preallocate a connection struct
 908 * in which case there could be two connection structs and cid would be
 909 * non-zero.
 910 */
 911struct iscsi_cls_conn *
 912iscsi_create_conn(struct iscsi_cls_session *session, int dd_size, uint32_t cid)
 913{
 914        struct iscsi_transport *transport = session->transport;
 915        struct iscsi_cls_conn *conn;
 916        unsigned long flags;
 917        int err;
 918
 919        conn = kzalloc(sizeof(*conn) + dd_size, GFP_KERNEL);
 920        if (!conn)
 921                return NULL;
 922        if (dd_size)
 923                conn->dd_data = &conn[1];
 924
 925        INIT_LIST_HEAD(&conn->conn_list);
 926        conn->transport = transport;
 927        conn->cid = cid;
 928
 929        /* this is released in the dev's release function */
 930        if (!get_device(&session->dev))
 931                goto free_conn;
 932
 933        dev_set_name(&conn->dev, "connection%d:%u", session->sid, cid);
 934        conn->dev.parent = &session->dev;
 935        conn->dev.release = iscsi_conn_release;
 936        err = device_register(&conn->dev);
 937        if (err) {
 938                iscsi_cls_session_printk(KERN_ERR, session, "could not "
 939                                         "register connection's dev\n");
 940                goto release_parent_ref;
 941        }
 942        transport_register_device(&conn->dev);
 943
 944        spin_lock_irqsave(&connlock, flags);
 945        list_add(&conn->conn_list, &connlist);
 946        conn->active = 1;
 947        spin_unlock_irqrestore(&connlock, flags);
 948
 949        ISCSI_DBG_TRANS_CONN(conn, "Completed conn creation\n");
 950        return conn;
 951
 952release_parent_ref:
 953        put_device(&session->dev);
 954free_conn:
 955        kfree(conn);
 956        return NULL;
 957}
 958
 959EXPORT_SYMBOL_GPL(iscsi_create_conn);
 960
 961/**
 962 * iscsi_destroy_conn - destroy iscsi class connection
 963 * @conn: iscsi cls session
 964 *
 965 * This can be called from a LLD or iscsi_transport.
 966 */
 967int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
 968{
 969        unsigned long flags;
 970
 971        spin_lock_irqsave(&connlock, flags);
 972        conn->active = 0;
 973        list_del(&conn->conn_list);
 974        spin_unlock_irqrestore(&connlock, flags);
 975
 976        transport_unregister_device(&conn->dev);
 977        ISCSI_DBG_TRANS_CONN(conn, "Completing conn destruction\n");
 978        device_unregister(&conn->dev);
 979        return 0;
 980}
 981EXPORT_SYMBOL_GPL(iscsi_destroy_conn);
 982
 983/*
 984 * iscsi interface functions
 985 */
 986static struct iscsi_internal *
 987iscsi_if_transport_lookup(struct iscsi_transport *tt)
 988{
 989        struct iscsi_internal *priv;
 990        unsigned long flags;
 991
 992        spin_lock_irqsave(&iscsi_transport_lock, flags);
 993        list_for_each_entry(priv, &iscsi_transports, list) {
 994                if (tt == priv->iscsi_transport) {
 995                        spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 996                        return priv;
 997                }
 998        }
 999        spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1000        return NULL;
1001}
1002
1003static int
1004iscsi_multicast_skb(struct sk_buff *skb, uint32_t group, gfp_t gfp)
1005{
1006        return nlmsg_multicast(nls, skb, 0, group, gfp);
1007}
1008
1009int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
1010                   char *data, uint32_t data_size)
1011{
1012        struct nlmsghdr *nlh;
1013        struct sk_buff *skb;
1014        struct iscsi_uevent *ev;
1015        char *pdu;
1016        struct iscsi_internal *priv;
1017        int len = NLMSG_SPACE(sizeof(*ev) + sizeof(struct iscsi_hdr) +
1018                              data_size);
1019
1020        priv = iscsi_if_transport_lookup(conn->transport);
1021        if (!priv)
1022                return -EINVAL;
1023
1024        skb = alloc_skb(len, GFP_ATOMIC);
1025        if (!skb) {
1026                iscsi_conn_error_event(conn, ISCSI_ERR_CONN_FAILED);
1027                iscsi_cls_conn_printk(KERN_ERR, conn, "can not deliver "
1028                                      "control PDU: OOM\n");
1029                return -ENOMEM;
1030        }
1031
1032        nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1033        ev = NLMSG_DATA(nlh);
1034        memset(ev, 0, sizeof(*ev));
1035        ev->transport_handle = iscsi_handle(conn->transport);
1036        ev->type = ISCSI_KEVENT_RECV_PDU;
1037        ev->r.recv_req.cid = conn->cid;
1038        ev->r.recv_req.sid = iscsi_conn_get_sid(conn);
1039        pdu = (char*)ev + sizeof(*ev);
1040        memcpy(pdu, hdr, sizeof(struct iscsi_hdr));
1041        memcpy(pdu + sizeof(struct iscsi_hdr), data, data_size);
1042
1043        return iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_ATOMIC);
1044}
1045EXPORT_SYMBOL_GPL(iscsi_recv_pdu);
1046
1047int iscsi_offload_mesg(struct Scsi_Host *shost,
1048                       struct iscsi_transport *transport, uint32_t type,
1049                       char *data, uint16_t data_size)
1050{
1051        struct nlmsghdr *nlh;
1052        struct sk_buff *skb;
1053        struct iscsi_uevent *ev;
1054        int len = NLMSG_SPACE(sizeof(*ev) + data_size);
1055
1056        skb = alloc_skb(len, GFP_ATOMIC);
1057        if (!skb) {
1058                printk(KERN_ERR "can not deliver iscsi offload message:OOM\n");
1059                return -ENOMEM;
1060        }
1061
1062        nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1063        ev = NLMSG_DATA(nlh);
1064        memset(ev, 0, sizeof(*ev));
1065        ev->type = type;
1066        ev->transport_handle = iscsi_handle(transport);
1067        switch (type) {
1068        case ISCSI_KEVENT_PATH_REQ:
1069                ev->r.req_path.host_no = shost->host_no;
1070                break;
1071        case ISCSI_KEVENT_IF_DOWN:
1072                ev->r.notify_if_down.host_no = shost->host_no;
1073                break;
1074        }
1075
1076        memcpy((char *)ev + sizeof(*ev), data, data_size);
1077
1078        return iscsi_multicast_skb(skb, ISCSI_NL_GRP_UIP, GFP_ATOMIC);
1079}
1080EXPORT_SYMBOL_GPL(iscsi_offload_mesg);
1081
1082void iscsi_conn_error_event(struct iscsi_cls_conn *conn, enum iscsi_err error)
1083{
1084        struct nlmsghdr *nlh;
1085        struct sk_buff  *skb;
1086        struct iscsi_uevent *ev;
1087        struct iscsi_internal *priv;
1088        int len = NLMSG_SPACE(sizeof(*ev));
1089
1090        priv = iscsi_if_transport_lookup(conn->transport);
1091        if (!priv)
1092                return;
1093
1094        skb = alloc_skb(len, GFP_ATOMIC);
1095        if (!skb) {
1096                iscsi_cls_conn_printk(KERN_ERR, conn, "gracefully ignored "
1097                                      "conn error (%d)\n", error);
1098                return;
1099        }
1100
1101        nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1102        ev = NLMSG_DATA(nlh);
1103        ev->transport_handle = iscsi_handle(conn->transport);
1104        ev->type = ISCSI_KEVENT_CONN_ERROR;
1105        ev->r.connerror.error = error;
1106        ev->r.connerror.cid = conn->cid;
1107        ev->r.connerror.sid = iscsi_conn_get_sid(conn);
1108
1109        iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_ATOMIC);
1110
1111        iscsi_cls_conn_printk(KERN_INFO, conn, "detected conn error (%d)\n",
1112                              error);
1113}
1114EXPORT_SYMBOL_GPL(iscsi_conn_error_event);
1115
1116static int
1117iscsi_if_send_reply(uint32_t group, int seq, int type, int done, int multi,
1118                    void *payload, int size)
1119{
1120        struct sk_buff  *skb;
1121        struct nlmsghdr *nlh;
1122        int len = NLMSG_SPACE(size);
1123        int flags = multi ? NLM_F_MULTI : 0;
1124        int t = done ? NLMSG_DONE : type;
1125
1126        skb = alloc_skb(len, GFP_ATOMIC);
1127        if (!skb) {
1128                printk(KERN_ERR "Could not allocate skb to send reply.\n");
1129                return -ENOMEM;
1130        }
1131
1132        nlh = __nlmsg_put(skb, 0, 0, t, (len - sizeof(*nlh)), 0);
1133        nlh->nlmsg_flags = flags;
1134        memcpy(NLMSG_DATA(nlh), payload, size);
1135        return iscsi_multicast_skb(skb, group, GFP_ATOMIC);
1136}
1137
1138static int
1139iscsi_if_get_stats(struct iscsi_transport *transport, struct nlmsghdr *nlh)
1140{
1141        struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1142        struct iscsi_stats *stats;
1143        struct sk_buff *skbstat;
1144        struct iscsi_cls_conn *conn;
1145        struct nlmsghdr *nlhstat;
1146        struct iscsi_uevent *evstat;
1147        struct iscsi_internal *priv;
1148        int len = NLMSG_SPACE(sizeof(*ev) +
1149                              sizeof(struct iscsi_stats) +
1150                              sizeof(struct iscsi_stats_custom) *
1151                              ISCSI_STATS_CUSTOM_MAX);
1152        int err = 0;
1153
1154        priv = iscsi_if_transport_lookup(transport);
1155        if (!priv)
1156                return -EINVAL;
1157
1158        conn = iscsi_conn_lookup(ev->u.get_stats.sid, ev->u.get_stats.cid);
1159        if (!conn)
1160                return -EEXIST;
1161
1162        do {
1163                int actual_size;
1164
1165                skbstat = alloc_skb(len, GFP_ATOMIC);
1166                if (!skbstat) {
1167                        iscsi_cls_conn_printk(KERN_ERR, conn, "can not "
1168                                              "deliver stats: OOM\n");
1169                        return -ENOMEM;
1170                }
1171
1172                nlhstat = __nlmsg_put(skbstat, 0, 0, 0,
1173                                      (len - sizeof(*nlhstat)), 0);
1174                evstat = NLMSG_DATA(nlhstat);
1175                memset(evstat, 0, sizeof(*evstat));
1176                evstat->transport_handle = iscsi_handle(conn->transport);
1177                evstat->type = nlh->nlmsg_type;
1178                evstat->u.get_stats.cid =
1179                        ev->u.get_stats.cid;
1180                evstat->u.get_stats.sid =
1181                        ev->u.get_stats.sid;
1182                stats = (struct iscsi_stats *)
1183                        ((char*)evstat + sizeof(*evstat));
1184                memset(stats, 0, sizeof(*stats));
1185
1186                transport->get_stats(conn, stats);
1187                actual_size = NLMSG_SPACE(sizeof(struct iscsi_uevent) +
1188                                          sizeof(struct iscsi_stats) +
1189                                          sizeof(struct iscsi_stats_custom) *
1190                                          stats->custom_length);
1191                actual_size -= sizeof(*nlhstat);
1192                actual_size = NLMSG_LENGTH(actual_size);
1193                skb_trim(skbstat, NLMSG_ALIGN(actual_size));
1194                nlhstat->nlmsg_len = actual_size;
1195
1196                err = iscsi_multicast_skb(skbstat, ISCSI_NL_GRP_ISCSID,
1197                                          GFP_ATOMIC);
1198        } while (err < 0 && err != -ECONNREFUSED);
1199
1200        return err;
1201}
1202
1203/**
1204 * iscsi_session_event - send session destr. completion event
1205 * @session: iscsi class session
1206 * @event: type of event
1207 */
1208int iscsi_session_event(struct iscsi_cls_session *session,
1209                        enum iscsi_uevent_e event)
1210{
1211        struct iscsi_internal *priv;
1212        struct Scsi_Host *shost;
1213        struct iscsi_uevent *ev;
1214        struct sk_buff  *skb;
1215        struct nlmsghdr *nlh;
1216        int rc, len = NLMSG_SPACE(sizeof(*ev));
1217
1218        priv = iscsi_if_transport_lookup(session->transport);
1219        if (!priv)
1220                return -EINVAL;
1221        shost = iscsi_session_to_shost(session);
1222
1223        skb = alloc_skb(len, GFP_KERNEL);
1224        if (!skb) {
1225                iscsi_cls_session_printk(KERN_ERR, session,
1226                                         "Cannot notify userspace of session "
1227                                         "event %u\n", event);
1228                return -ENOMEM;
1229        }
1230
1231        nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1232        ev = NLMSG_DATA(nlh);
1233        ev->transport_handle = iscsi_handle(session->transport);
1234
1235        ev->type = event;
1236        switch (event) {
1237        case ISCSI_KEVENT_DESTROY_SESSION:
1238                ev->r.d_session.host_no = shost->host_no;
1239                ev->r.d_session.sid = session->sid;
1240                break;
1241        case ISCSI_KEVENT_CREATE_SESSION:
1242                ev->r.c_session_ret.host_no = shost->host_no;
1243                ev->r.c_session_ret.sid = session->sid;
1244                break;
1245        case ISCSI_KEVENT_UNBIND_SESSION:
1246                ev->r.unbind_session.host_no = shost->host_no;
1247                ev->r.unbind_session.sid = session->sid;
1248                break;
1249        default:
1250                iscsi_cls_session_printk(KERN_ERR, session, "Invalid event "
1251                                         "%u.\n", event);
1252                kfree_skb(skb);
1253                return -EINVAL;
1254        }
1255
1256        /*
1257         * this will occur if the daemon is not up, so we just warn
1258         * the user and when the daemon is restarted it will handle it
1259         */
1260        rc = iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_KERNEL);
1261        if (rc == -ESRCH)
1262                iscsi_cls_session_printk(KERN_ERR, session,
1263                                         "Cannot notify userspace of session "
1264                                         "event %u. Check iscsi daemon\n",
1265                                         event);
1266
1267        ISCSI_DBG_TRANS_SESSION(session, "Completed handling event %d rc %d\n",
1268                                event, rc);
1269        return rc;
1270}
1271EXPORT_SYMBOL_GPL(iscsi_session_event);
1272
1273static int
1274iscsi_if_create_session(struct iscsi_internal *priv, struct iscsi_endpoint *ep,
1275                        struct iscsi_uevent *ev, uint32_t initial_cmdsn,
1276                        uint16_t cmds_max, uint16_t queue_depth)
1277{
1278        struct iscsi_transport *transport = priv->iscsi_transport;
1279        struct iscsi_cls_session *session;
1280        struct Scsi_Host *shost;
1281
1282        session = transport->create_session(ep, cmds_max, queue_depth,
1283                                            initial_cmdsn);
1284        if (!session)
1285                return -ENOMEM;
1286
1287        shost = iscsi_session_to_shost(session);
1288        ev->r.c_session_ret.host_no = shost->host_no;
1289        ev->r.c_session_ret.sid = session->sid;
1290        ISCSI_DBG_TRANS_SESSION(session,
1291                                "Completed creating transport session\n");
1292        return 0;
1293}
1294
1295static int
1296iscsi_if_create_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1297{
1298        struct iscsi_cls_conn *conn;
1299        struct iscsi_cls_session *session;
1300
1301        session = iscsi_session_lookup(ev->u.c_conn.sid);
1302        if (!session) {
1303                printk(KERN_ERR "iscsi: invalid session %d.\n",
1304                       ev->u.c_conn.sid);
1305                return -EINVAL;
1306        }
1307
1308        conn = transport->create_conn(session, ev->u.c_conn.cid);
1309        if (!conn) {
1310                iscsi_cls_session_printk(KERN_ERR, session,
1311                                         "couldn't create a new connection.");
1312                return -ENOMEM;
1313        }
1314
1315        ev->r.c_conn_ret.sid = session->sid;
1316        ev->r.c_conn_ret.cid = conn->cid;
1317
1318        ISCSI_DBG_TRANS_CONN(conn, "Completed creating transport conn\n");
1319        return 0;
1320}
1321
1322static int
1323iscsi_if_destroy_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1324{
1325        struct iscsi_cls_conn *conn;
1326
1327        conn = iscsi_conn_lookup(ev->u.d_conn.sid, ev->u.d_conn.cid);
1328        if (!conn)
1329                return -EINVAL;
1330
1331        ISCSI_DBG_TRANS_CONN(conn, "Destroying transport conn\n");
1332        if (transport->destroy_conn)
1333                transport->destroy_conn(conn);
1334
1335        return 0;
1336}
1337
1338static int
1339iscsi_set_param(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1340{
1341        char *data = (char*)ev + sizeof(*ev);
1342        struct iscsi_cls_conn *conn;
1343        struct iscsi_cls_session *session;
1344        int err = 0, value = 0;
1345
1346        session = iscsi_session_lookup(ev->u.set_param.sid);
1347        conn = iscsi_conn_lookup(ev->u.set_param.sid, ev->u.set_param.cid);
1348        if (!conn || !session)
1349                return -EINVAL;
1350
1351        switch (ev->u.set_param.param) {
1352        case ISCSI_PARAM_SESS_RECOVERY_TMO:
1353                sscanf(data, "%d", &value);
1354                session->recovery_tmo = value;
1355                break;
1356        default:
1357                err = transport->set_param(conn, ev->u.set_param.param,
1358                                           data, ev->u.set_param.len);
1359        }
1360
1361        return err;
1362}
1363
1364static int iscsi_if_ep_connect(struct iscsi_transport *transport,
1365                               struct iscsi_uevent *ev, int msg_type)
1366{
1367        struct iscsi_endpoint *ep;
1368        struct sockaddr *dst_addr;
1369        struct Scsi_Host *shost = NULL;
1370        int non_blocking, err = 0;
1371
1372        if (!transport->ep_connect)
1373                return -EINVAL;
1374
1375        if (msg_type == ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST) {
1376                shost = scsi_host_lookup(ev->u.ep_connect_through_host.host_no);
1377                if (!shost) {
1378                        printk(KERN_ERR "ep connect failed. Could not find "
1379                               "host no %u\n",
1380                               ev->u.ep_connect_through_host.host_no);
1381                        return -ENODEV;
1382                }
1383                non_blocking = ev->u.ep_connect_through_host.non_blocking;
1384        } else
1385                non_blocking = ev->u.ep_connect.non_blocking;
1386
1387        dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1388        ep = transport->ep_connect(shost, dst_addr, non_blocking);
1389        if (IS_ERR(ep)) {
1390                err = PTR_ERR(ep);
1391                goto release_host;
1392        }
1393
1394        ev->r.ep_connect_ret.handle = ep->id;
1395release_host:
1396        if (shost)
1397                scsi_host_put(shost);
1398        return err;
1399}
1400
1401static int
1402iscsi_if_transport_ep(struct iscsi_transport *transport,
1403                      struct iscsi_uevent *ev, int msg_type)
1404{
1405        struct iscsi_endpoint *ep;
1406        int rc = 0;
1407
1408        switch (msg_type) {
1409        case ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST:
1410        case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1411                rc = iscsi_if_ep_connect(transport, ev, msg_type);
1412                break;
1413        case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1414                if (!transport->ep_poll)
1415                        return -EINVAL;
1416
1417                ep = iscsi_lookup_endpoint(ev->u.ep_poll.ep_handle);
1418                if (!ep)
1419                        return -EINVAL;
1420
1421                ev->r.retcode = transport->ep_poll(ep,
1422                                                   ev->u.ep_poll.timeout_ms);
1423                break;
1424        case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1425                if (!transport->ep_disconnect)
1426                        return -EINVAL;
1427
1428                ep = iscsi_lookup_endpoint(ev->u.ep_disconnect.ep_handle);
1429                if (!ep)
1430                        return -EINVAL;
1431
1432                transport->ep_disconnect(ep);
1433                break;
1434        }
1435        return rc;
1436}
1437
1438static int
1439iscsi_tgt_dscvr(struct iscsi_transport *transport,
1440                struct iscsi_uevent *ev)
1441{
1442        struct Scsi_Host *shost;
1443        struct sockaddr *dst_addr;
1444        int err;
1445
1446        if (!transport->tgt_dscvr)
1447                return -EINVAL;
1448
1449        shost = scsi_host_lookup(ev->u.tgt_dscvr.host_no);
1450        if (!shost) {
1451                printk(KERN_ERR "target discovery could not find host no %u\n",
1452                       ev->u.tgt_dscvr.host_no);
1453                return -ENODEV;
1454        }
1455
1456
1457        dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1458        err = transport->tgt_dscvr(shost, ev->u.tgt_dscvr.type,
1459                                   ev->u.tgt_dscvr.enable, dst_addr);
1460        scsi_host_put(shost);
1461        return err;
1462}
1463
1464static int
1465iscsi_set_host_param(struct iscsi_transport *transport,
1466                     struct iscsi_uevent *ev)
1467{
1468        char *data = (char*)ev + sizeof(*ev);
1469        struct Scsi_Host *shost;
1470        int err;
1471
1472        if (!transport->set_host_param)
1473                return -ENOSYS;
1474
1475        shost = scsi_host_lookup(ev->u.set_host_param.host_no);
1476        if (!shost) {
1477                printk(KERN_ERR "set_host_param could not find host no %u\n",
1478                       ev->u.set_host_param.host_no);
1479                return -ENODEV;
1480        }
1481
1482        err = transport->set_host_param(shost, ev->u.set_host_param.param,
1483                                        data, ev->u.set_host_param.len);
1484        scsi_host_put(shost);
1485        return err;
1486}
1487
1488static int
1489iscsi_set_path(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1490{
1491        struct Scsi_Host *shost;
1492        struct iscsi_path *params;
1493        int err;
1494
1495        if (!transport->set_path)
1496                return -ENOSYS;
1497
1498        shost = scsi_host_lookup(ev->u.set_path.host_no);
1499        if (!shost) {
1500                printk(KERN_ERR "set path could not find host no %u\n",
1501                       ev->u.set_path.host_no);
1502                return -ENODEV;
1503        }
1504
1505        params = (struct iscsi_path *)((char *)ev + sizeof(*ev));
1506        err = transport->set_path(shost, params);
1507
1508        scsi_host_put(shost);
1509        return err;
1510}
1511
1512static int
1513iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, uint32_t *group)
1514{
1515        int err = 0;
1516        struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1517        struct iscsi_transport *transport = NULL;
1518        struct iscsi_internal *priv;
1519        struct iscsi_cls_session *session;
1520        struct iscsi_cls_conn *conn;
1521        struct iscsi_endpoint *ep = NULL;
1522
1523        if (nlh->nlmsg_type == ISCSI_UEVENT_PATH_UPDATE)
1524                *group = ISCSI_NL_GRP_UIP;
1525        else
1526                *group = ISCSI_NL_GRP_ISCSID;
1527
1528        priv = iscsi_if_transport_lookup(iscsi_ptr(ev->transport_handle));
1529        if (!priv)
1530                return -EINVAL;
1531        transport = priv->iscsi_transport;
1532
1533        if (!try_module_get(transport->owner))
1534                return -EINVAL;
1535
1536        switch (nlh->nlmsg_type) {
1537        case ISCSI_UEVENT_CREATE_SESSION:
1538                err = iscsi_if_create_session(priv, ep, ev,
1539                                              ev->u.c_session.initial_cmdsn,
1540                                              ev->u.c_session.cmds_max,
1541                                              ev->u.c_session.queue_depth);
1542                break;
1543        case ISCSI_UEVENT_CREATE_BOUND_SESSION:
1544                ep = iscsi_lookup_endpoint(ev->u.c_bound_session.ep_handle);
1545                if (!ep) {
1546                        err = -EINVAL;
1547                        break;
1548                }
1549
1550                err = iscsi_if_create_session(priv, ep, ev,
1551                                        ev->u.c_bound_session.initial_cmdsn,
1552                                        ev->u.c_bound_session.cmds_max,
1553                                        ev->u.c_bound_session.queue_depth);
1554                break;
1555        case ISCSI_UEVENT_DESTROY_SESSION:
1556                session = iscsi_session_lookup(ev->u.d_session.sid);
1557                if (session)
1558                        transport->destroy_session(session);
1559                else
1560                        err = -EINVAL;
1561                break;
1562        case ISCSI_UEVENT_UNBIND_SESSION:
1563                session = iscsi_session_lookup(ev->u.d_session.sid);
1564                if (session)
1565                        scsi_queue_work(iscsi_session_to_shost(session),
1566                                        &session->unbind_work);
1567                else
1568                        err = -EINVAL;
1569                break;
1570        case ISCSI_UEVENT_CREATE_CONN:
1571                err = iscsi_if_create_conn(transport, ev);
1572                break;
1573        case ISCSI_UEVENT_DESTROY_CONN:
1574                err = iscsi_if_destroy_conn(transport, ev);
1575                break;
1576        case ISCSI_UEVENT_BIND_CONN:
1577                session = iscsi_session_lookup(ev->u.b_conn.sid);
1578                conn = iscsi_conn_lookup(ev->u.b_conn.sid, ev->u.b_conn.cid);
1579
1580                if (session && conn)
1581                        ev->r.retcode = transport->bind_conn(session, conn,
1582                                        ev->u.b_conn.transport_eph,
1583                                        ev->u.b_conn.is_leading);
1584                else
1585                        err = -EINVAL;
1586                break;
1587        case ISCSI_UEVENT_SET_PARAM:
1588                err = iscsi_set_param(transport, ev);
1589                break;
1590        case ISCSI_UEVENT_START_CONN:
1591                conn = iscsi_conn_lookup(ev->u.start_conn.sid, ev->u.start_conn.cid);
1592                if (conn)
1593                        ev->r.retcode = transport->start_conn(conn);
1594                else
1595                        err = -EINVAL;
1596                break;
1597        case ISCSI_UEVENT_STOP_CONN:
1598                conn = iscsi_conn_lookup(ev->u.stop_conn.sid, ev->u.stop_conn.cid);
1599                if (conn)
1600                        transport->stop_conn(conn, ev->u.stop_conn.flag);
1601                else
1602                        err = -EINVAL;
1603                break;
1604        case ISCSI_UEVENT_SEND_PDU:
1605                conn = iscsi_conn_lookup(ev->u.send_pdu.sid, ev->u.send_pdu.cid);
1606                if (conn)
1607                        ev->r.retcode = transport->send_pdu(conn,
1608                                (struct iscsi_hdr*)((char*)ev + sizeof(*ev)),
1609                                (char*)ev + sizeof(*ev) + ev->u.send_pdu.hdr_size,
1610                                ev->u.send_pdu.data_size);
1611                else
1612                        err = -EINVAL;
1613                break;
1614        case ISCSI_UEVENT_GET_STATS:
1615                err = iscsi_if_get_stats(transport, nlh);
1616                break;
1617        case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1618        case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1619        case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1620        case ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST:
1621                err = iscsi_if_transport_ep(transport, ev, nlh->nlmsg_type);
1622                break;
1623        case ISCSI_UEVENT_TGT_DSCVR:
1624                err = iscsi_tgt_dscvr(transport, ev);
1625                break;
1626        case ISCSI_UEVENT_SET_HOST_PARAM:
1627                err = iscsi_set_host_param(transport, ev);
1628                break;
1629        case ISCSI_UEVENT_PATH_UPDATE:
1630                err = iscsi_set_path(transport, ev);
1631                break;
1632        default:
1633                err = -ENOSYS;
1634                break;
1635        }
1636
1637        module_put(transport->owner);
1638        return err;
1639}
1640
1641/*
1642 * Get message from skb.  Each message is processed by iscsi_if_recv_msg.
1643 * Malformed skbs with wrong lengths or invalid creds are not processed.
1644 */
1645static void
1646iscsi_if_rx(struct sk_buff *skb)
1647{
1648        mutex_lock(&rx_queue_mutex);
1649        while (skb->len >= NLMSG_SPACE(0)) {
1650                int err;
1651                uint32_t rlen;
1652                struct nlmsghdr *nlh;
1653                struct iscsi_uevent *ev;
1654                uint32_t group;
1655
1656                nlh = nlmsg_hdr(skb);
1657                if (nlh->nlmsg_len < sizeof(*nlh) ||
1658                    skb->len < nlh->nlmsg_len) {
1659                        break;
1660                }
1661
1662                ev = NLMSG_DATA(nlh);
1663                rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1664                if (rlen > skb->len)
1665                        rlen = skb->len;
1666
1667                err = iscsi_if_recv_msg(skb, nlh, &group);
1668                if (err) {
1669                        ev->type = ISCSI_KEVENT_IF_ERROR;
1670                        ev->iferror = err;
1671                }
1672                do {
1673                        /*
1674                         * special case for GET_STATS:
1675                         * on success - sending reply and stats from
1676                         * inside of if_recv_msg(),
1677                         * on error - fall through.
1678                         */
1679                        if (ev->type == ISCSI_UEVENT_GET_STATS && !err)
1680                                break;
1681                        err = iscsi_if_send_reply(group, nlh->nlmsg_seq,
1682                                nlh->nlmsg_type, 0, 0, ev, sizeof(*ev));
1683                } while (err < 0 && err != -ECONNREFUSED);
1684                skb_pull(skb, rlen);
1685        }
1686        mutex_unlock(&rx_queue_mutex);
1687}
1688
1689#define ISCSI_CLASS_ATTR(_prefix,_name,_mode,_show,_store)              \
1690struct device_attribute dev_attr_##_prefix##_##_name =  \
1691        __ATTR(_name,_mode,_show,_store)
1692
1693/*
1694 * iSCSI connection attrs
1695 */
1696#define iscsi_conn_attr_show(param)                                     \
1697static ssize_t                                                          \
1698show_conn_param_##param(struct device *dev,                             \
1699                        struct device_attribute *attr, char *buf)       \
1700{                                                                       \
1701        struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev->parent);   \
1702        struct iscsi_transport *t = conn->transport;                    \
1703        return t->get_conn_param(conn, param, buf);                     \
1704}
1705
1706#define iscsi_conn_attr(field, param)                                   \
1707        iscsi_conn_attr_show(param)                                     \
1708static ISCSI_CLASS_ATTR(conn, field, S_IRUGO, show_conn_param_##param,  \
1709                        NULL);
1710
1711iscsi_conn_attr(max_recv_dlength, ISCSI_PARAM_MAX_RECV_DLENGTH);
1712iscsi_conn_attr(max_xmit_dlength, ISCSI_PARAM_MAX_XMIT_DLENGTH);
1713iscsi_conn_attr(header_digest, ISCSI_PARAM_HDRDGST_EN);
1714iscsi_conn_attr(data_digest, ISCSI_PARAM_DATADGST_EN);
1715iscsi_conn_attr(ifmarker, ISCSI_PARAM_IFMARKER_EN);
1716iscsi_conn_attr(ofmarker, ISCSI_PARAM_OFMARKER_EN);
1717iscsi_conn_attr(persistent_port, ISCSI_PARAM_PERSISTENT_PORT);
1718iscsi_conn_attr(port, ISCSI_PARAM_CONN_PORT);
1719iscsi_conn_attr(exp_statsn, ISCSI_PARAM_EXP_STATSN);
1720iscsi_conn_attr(persistent_address, ISCSI_PARAM_PERSISTENT_ADDRESS);
1721iscsi_conn_attr(address, ISCSI_PARAM_CONN_ADDRESS);
1722iscsi_conn_attr(ping_tmo, ISCSI_PARAM_PING_TMO);
1723iscsi_conn_attr(recv_tmo, ISCSI_PARAM_RECV_TMO);
1724
1725/*
1726 * iSCSI session attrs
1727 */
1728#define iscsi_session_attr_show(param, perm)                            \
1729static ssize_t                                                          \
1730show_session_param_##param(struct device *dev,                          \
1731                           struct device_attribute *attr, char *buf)    \
1732{                                                                       \
1733        struct iscsi_cls_session *session =                             \
1734                iscsi_dev_to_session(dev->parent);                      \
1735        struct iscsi_transport *t = session->transport;                 \
1736                                                                        \
1737        if (perm && !capable(CAP_SYS_ADMIN))                            \
1738                return -EACCES;                                         \
1739        return t->get_session_param(session, param, buf);               \
1740}
1741
1742#define iscsi_session_attr(field, param, perm)                          \
1743        iscsi_session_attr_show(param, perm)                            \
1744static ISCSI_CLASS_ATTR(sess, field, S_IRUGO, show_session_param_##param, \
1745                        NULL);
1746
1747iscsi_session_attr(targetname, ISCSI_PARAM_TARGET_NAME, 0);
1748iscsi_session_attr(initial_r2t, ISCSI_PARAM_INITIAL_R2T_EN, 0);
1749iscsi_session_attr(max_outstanding_r2t, ISCSI_PARAM_MAX_R2T, 0);
1750iscsi_session_attr(immediate_data, ISCSI_PARAM_IMM_DATA_EN, 0);
1751iscsi_session_attr(first_burst_len, ISCSI_PARAM_FIRST_BURST, 0);
1752iscsi_session_attr(max_burst_len, ISCSI_PARAM_MAX_BURST, 0);
1753iscsi_session_attr(data_pdu_in_order, ISCSI_PARAM_PDU_INORDER_EN, 0);
1754iscsi_session_attr(data_seq_in_order, ISCSI_PARAM_DATASEQ_INORDER_EN, 0);
1755iscsi_session_attr(erl, ISCSI_PARAM_ERL, 0);
1756iscsi_session_attr(tpgt, ISCSI_PARAM_TPGT, 0);
1757iscsi_session_attr(username, ISCSI_PARAM_USERNAME, 1);
1758iscsi_session_attr(username_in, ISCSI_PARAM_USERNAME_IN, 1);
1759iscsi_session_attr(password, ISCSI_PARAM_PASSWORD, 1);
1760iscsi_session_attr(password_in, ISCSI_PARAM_PASSWORD_IN, 1);
1761iscsi_session_attr(fast_abort, ISCSI_PARAM_FAST_ABORT, 0);
1762iscsi_session_attr(abort_tmo, ISCSI_PARAM_ABORT_TMO, 0);
1763iscsi_session_attr(lu_reset_tmo, ISCSI_PARAM_LU_RESET_TMO, 0);
1764iscsi_session_attr(tgt_reset_tmo, ISCSI_PARAM_TGT_RESET_TMO, 0);
1765iscsi_session_attr(ifacename, ISCSI_PARAM_IFACE_NAME, 0);
1766iscsi_session_attr(initiatorname, ISCSI_PARAM_INITIATOR_NAME, 0)
1767
1768static ssize_t
1769show_priv_session_state(struct device *dev, struct device_attribute *attr,
1770                        char *buf)
1771{
1772        struct iscsi_cls_session *session = iscsi_dev_to_session(dev->parent);
1773        return sprintf(buf, "%s\n", iscsi_session_state_name(session->state));
1774}
1775static ISCSI_CLASS_ATTR(priv_sess, state, S_IRUGO, show_priv_session_state,
1776                        NULL);
1777
1778#define iscsi_priv_session_attr_show(field, format)                     \
1779static ssize_t                                                          \
1780show_priv_session_##field(struct device *dev,                           \
1781                          struct device_attribute *attr, char *buf)     \
1782{                                                                       \
1783        struct iscsi_cls_session *session =                             \
1784                        iscsi_dev_to_session(dev->parent);              \
1785        return sprintf(buf, format"\n", session->field);                \
1786}
1787
1788#define iscsi_priv_session_attr(field, format)                          \
1789        iscsi_priv_session_attr_show(field, format)                     \
1790static ISCSI_CLASS_ATTR(priv_sess, field, S_IRUGO, show_priv_session_##field, \
1791                        NULL)
1792iscsi_priv_session_attr(recovery_tmo, "%d");
1793
1794/*
1795 * iSCSI host attrs
1796 */
1797#define iscsi_host_attr_show(param)                                     \
1798static ssize_t                                                          \
1799show_host_param_##param(struct device *dev,                             \
1800                        struct device_attribute *attr, char *buf)       \
1801{                                                                       \
1802        struct Scsi_Host *shost = transport_class_to_shost(dev);        \
1803        struct iscsi_internal *priv = to_iscsi_internal(shost->transportt); \
1804        return priv->iscsi_transport->get_host_param(shost, param, buf); \
1805}
1806
1807#define iscsi_host_attr(field, param)                                   \
1808        iscsi_host_attr_show(param)                                     \
1809static ISCSI_CLASS_ATTR(host, field, S_IRUGO, show_host_param_##param,  \
1810                        NULL);
1811
1812iscsi_host_attr(netdev, ISCSI_HOST_PARAM_NETDEV_NAME);
1813iscsi_host_attr(hwaddress, ISCSI_HOST_PARAM_HWADDRESS);
1814iscsi_host_attr(ipaddress, ISCSI_HOST_PARAM_IPADDRESS);
1815iscsi_host_attr(initiatorname, ISCSI_HOST_PARAM_INITIATOR_NAME);
1816
1817#define SETUP_PRIV_SESSION_RD_ATTR(field)                               \
1818do {                                                                    \
1819        priv->session_attrs[count] = &dev_attr_priv_sess_##field; \
1820        count++;                                                        \
1821} while (0)
1822
1823
1824#define SETUP_SESSION_RD_ATTR(field, param_flag)                        \
1825do {                                                                    \
1826        if (tt->param_mask & param_flag) {                              \
1827                priv->session_attrs[count] = &dev_attr_sess_##field; \
1828                count++;                                                \
1829        }                                                               \
1830} while (0)
1831
1832#define SETUP_CONN_RD_ATTR(field, param_flag)                           \
1833do {                                                                    \
1834        if (tt->param_mask & param_flag) {                              \
1835                priv->conn_attrs[count] = &dev_attr_conn_##field; \
1836                count++;                                                \
1837        }                                                               \
1838} while (0)
1839
1840#define SETUP_HOST_RD_ATTR(field, param_flag)                           \
1841do {                                                                    \
1842        if (tt->host_param_mask & param_flag) {                         \
1843                priv->host_attrs[count] = &dev_attr_host_##field; \
1844                count++;                                                \
1845        }                                                               \
1846} while (0)
1847
1848static int iscsi_session_match(struct attribute_container *cont,
1849                           struct device *dev)
1850{
1851        struct iscsi_cls_session *session;
1852        struct Scsi_Host *shost;
1853        struct iscsi_internal *priv;
1854
1855        if (!iscsi_is_session_dev(dev))
1856                return 0;
1857
1858        session = iscsi_dev_to_session(dev);
1859        shost = iscsi_session_to_shost(session);
1860        if (!shost->transportt)
1861                return 0;
1862
1863        priv = to_iscsi_internal(shost->transportt);
1864        if (priv->session_cont.ac.class != &iscsi_session_class.class)
1865                return 0;
1866
1867        return &priv->session_cont.ac == cont;
1868}
1869
1870static int iscsi_conn_match(struct attribute_container *cont,
1871                           struct device *dev)
1872{
1873        struct iscsi_cls_session *session;
1874        struct iscsi_cls_conn *conn;
1875        struct Scsi_Host *shost;
1876        struct iscsi_internal *priv;
1877
1878        if (!iscsi_is_conn_dev(dev))
1879                return 0;
1880
1881        conn = iscsi_dev_to_conn(dev);
1882        session = iscsi_dev_to_session(conn->dev.parent);
1883        shost = iscsi_session_to_shost(session);
1884
1885        if (!shost->transportt)
1886                return 0;
1887
1888        priv = to_iscsi_internal(shost->transportt);
1889        if (priv->conn_cont.ac.class != &iscsi_connection_class.class)
1890                return 0;
1891
1892        return &priv->conn_cont.ac == cont;
1893}
1894
1895static int iscsi_host_match(struct attribute_container *cont,
1896                            struct device *dev)
1897{
1898        struct Scsi_Host *shost;
1899        struct iscsi_internal *priv;
1900
1901        if (!scsi_is_host_device(dev))
1902                return 0;
1903
1904        shost = dev_to_shost(dev);
1905        if (!shost->transportt  ||
1906            shost->transportt->host_attrs.ac.class != &iscsi_host_class.class)
1907                return 0;
1908
1909        priv = to_iscsi_internal(shost->transportt);
1910        return &priv->t.host_attrs.ac == cont;
1911}
1912
1913struct scsi_transport_template *
1914iscsi_register_transport(struct iscsi_transport *tt)
1915{
1916        struct iscsi_internal *priv;
1917        unsigned long flags;
1918        int count = 0, err;
1919
1920        BUG_ON(!tt);
1921
1922        priv = iscsi_if_transport_lookup(tt);
1923        if (priv)
1924                return NULL;
1925
1926        priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1927        if (!priv)
1928                return NULL;
1929        INIT_LIST_HEAD(&priv->list);
1930        priv->iscsi_transport = tt;
1931        priv->t.user_scan = iscsi_user_scan;
1932        priv->t.create_work_queue = 1;
1933
1934        priv->dev.class = &iscsi_transport_class;
1935        dev_set_name(&priv->dev, "%s", tt->name);
1936        err = device_register(&priv->dev);
1937        if (err)
1938                goto free_priv;
1939
1940        err = sysfs_create_group(&priv->dev.kobj, &iscsi_transport_group);
1941        if (err)
1942                goto unregister_dev;
1943
1944        /* host parameters */
1945        priv->t.host_attrs.ac.attrs = &priv->host_attrs[0];
1946        priv->t.host_attrs.ac.class = &iscsi_host_class.class;
1947        priv->t.host_attrs.ac.match = iscsi_host_match;
1948        priv->t.host_size = sizeof(struct iscsi_cls_host);
1949        transport_container_register(&priv->t.host_attrs);
1950
1951        SETUP_HOST_RD_ATTR(netdev, ISCSI_HOST_NETDEV_NAME);
1952        SETUP_HOST_RD_ATTR(ipaddress, ISCSI_HOST_IPADDRESS);
1953        SETUP_HOST_RD_ATTR(hwaddress, ISCSI_HOST_HWADDRESS);
1954        SETUP_HOST_RD_ATTR(initiatorname, ISCSI_HOST_INITIATOR_NAME);
1955        BUG_ON(count > ISCSI_HOST_ATTRS);
1956        priv->host_attrs[count] = NULL;
1957        count = 0;
1958
1959        /* connection parameters */
1960        priv->conn_cont.ac.attrs = &priv->conn_attrs[0];
1961        priv->conn_cont.ac.class = &iscsi_connection_class.class;
1962        priv->conn_cont.ac.match = iscsi_conn_match;
1963        transport_container_register(&priv->conn_cont);
1964
1965        SETUP_CONN_RD_ATTR(max_recv_dlength, ISCSI_MAX_RECV_DLENGTH);
1966        SETUP_CONN_RD_ATTR(max_xmit_dlength, ISCSI_MAX_XMIT_DLENGTH);
1967        SETUP_CONN_RD_ATTR(header_digest, ISCSI_HDRDGST_EN);
1968        SETUP_CONN_RD_ATTR(data_digest, ISCSI_DATADGST_EN);
1969        SETUP_CONN_RD_ATTR(ifmarker, ISCSI_IFMARKER_EN);
1970        SETUP_CONN_RD_ATTR(ofmarker, ISCSI_OFMARKER_EN);
1971        SETUP_CONN_RD_ATTR(address, ISCSI_CONN_ADDRESS);
1972        SETUP_CONN_RD_ATTR(port, ISCSI_CONN_PORT);
1973        SETUP_CONN_RD_ATTR(exp_statsn, ISCSI_EXP_STATSN);
1974        SETUP_CONN_RD_ATTR(persistent_address, ISCSI_PERSISTENT_ADDRESS);
1975        SETUP_CONN_RD_ATTR(persistent_port, ISCSI_PERSISTENT_PORT);
1976        SETUP_CONN_RD_ATTR(ping_tmo, ISCSI_PING_TMO);
1977        SETUP_CONN_RD_ATTR(recv_tmo, ISCSI_RECV_TMO);
1978
1979        BUG_ON(count > ISCSI_CONN_ATTRS);
1980        priv->conn_attrs[count] = NULL;
1981        count = 0;
1982
1983        /* session parameters */
1984        priv->session_cont.ac.attrs = &priv->session_attrs[0];
1985        priv->session_cont.ac.class = &iscsi_session_class.class;
1986        priv->session_cont.ac.match = iscsi_session_match;
1987        transport_container_register(&priv->session_cont);
1988
1989        SETUP_SESSION_RD_ATTR(initial_r2t, ISCSI_INITIAL_R2T_EN);
1990        SETUP_SESSION_RD_ATTR(max_outstanding_r2t, ISCSI_MAX_R2T);
1991        SETUP_SESSION_RD_ATTR(immediate_data, ISCSI_IMM_DATA_EN);
1992        SETUP_SESSION_RD_ATTR(first_burst_len, ISCSI_FIRST_BURST);
1993        SETUP_SESSION_RD_ATTR(max_burst_len, ISCSI_MAX_BURST);
1994        SETUP_SESSION_RD_ATTR(data_pdu_in_order, ISCSI_PDU_INORDER_EN);
1995        SETUP_SESSION_RD_ATTR(data_seq_in_order, ISCSI_DATASEQ_INORDER_EN);
1996        SETUP_SESSION_RD_ATTR(erl, ISCSI_ERL);
1997        SETUP_SESSION_RD_ATTR(targetname, ISCSI_TARGET_NAME);
1998        SETUP_SESSION_RD_ATTR(tpgt, ISCSI_TPGT);
1999        SETUP_SESSION_RD_ATTR(password, ISCSI_USERNAME);
2000        SETUP_SESSION_RD_ATTR(password_in, ISCSI_USERNAME_IN);
2001        SETUP_SESSION_RD_ATTR(username, ISCSI_PASSWORD);
2002        SETUP_SESSION_RD_ATTR(username_in, ISCSI_PASSWORD_IN);
2003        SETUP_SESSION_RD_ATTR(fast_abort, ISCSI_FAST_ABORT);
2004        SETUP_SESSION_RD_ATTR(abort_tmo, ISCSI_ABORT_TMO);
2005        SETUP_SESSION_RD_ATTR(lu_reset_tmo,ISCSI_LU_RESET_TMO);
2006        SETUP_SESSION_RD_ATTR(tgt_reset_tmo,ISCSI_TGT_RESET_TMO);
2007        SETUP_SESSION_RD_ATTR(ifacename, ISCSI_IFACE_NAME);
2008        SETUP_SESSION_RD_ATTR(initiatorname, ISCSI_INITIATOR_NAME);
2009        SETUP_PRIV_SESSION_RD_ATTR(recovery_tmo);
2010        SETUP_PRIV_SESSION_RD_ATTR(state);
2011
2012        BUG_ON(count > ISCSI_SESSION_ATTRS);
2013        priv->session_attrs[count] = NULL;
2014
2015        spin_lock_irqsave(&iscsi_transport_lock, flags);
2016        list_add(&priv->list, &iscsi_transports);
2017        spin_unlock_irqrestore(&iscsi_transport_lock, flags);
2018
2019        printk(KERN_NOTICE "iscsi: registered transport (%s)\n", tt->name);
2020        return &priv->t;
2021
2022unregister_dev:
2023        device_unregister(&priv->dev);
2024        return NULL;
2025free_priv:
2026        kfree(priv);
2027        return NULL;
2028}
2029EXPORT_SYMBOL_GPL(iscsi_register_transport);
2030
2031int iscsi_unregister_transport(struct iscsi_transport *tt)
2032{
2033        struct iscsi_internal *priv;
2034        unsigned long flags;
2035
2036        BUG_ON(!tt);
2037
2038        mutex_lock(&rx_queue_mutex);
2039
2040        priv = iscsi_if_transport_lookup(tt);
2041        BUG_ON (!priv);
2042
2043        spin_lock_irqsave(&iscsi_transport_lock, flags);
2044        list_del(&priv->list);
2045        spin_unlock_irqrestore(&iscsi_transport_lock, flags);
2046
2047        transport_container_unregister(&priv->conn_cont);
2048        transport_container_unregister(&priv->session_cont);
2049        transport_container_unregister(&priv->t.host_attrs);
2050
2051        sysfs_remove_group(&priv->dev.kobj, &iscsi_transport_group);
2052        device_unregister(&priv->dev);
2053        mutex_unlock(&rx_queue_mutex);
2054
2055        return 0;
2056}
2057EXPORT_SYMBOL_GPL(iscsi_unregister_transport);
2058
2059static __init int iscsi_transport_init(void)
2060{
2061        int err;
2062
2063        printk(KERN_INFO "Loading iSCSI transport class v%s.\n",
2064                ISCSI_TRANSPORT_VERSION);
2065
2066        atomic_set(&iscsi_session_nr, 0);
2067
2068        err = class_register(&iscsi_transport_class);
2069        if (err)
2070                return err;
2071
2072        err = class_register(&iscsi_endpoint_class);
2073        if (err)
2074                goto unregister_transport_class;
2075
2076        err = transport_class_register(&iscsi_host_class);
2077        if (err)
2078                goto unregister_endpoint_class;
2079
2080        err = transport_class_register(&iscsi_connection_class);
2081        if (err)
2082                goto unregister_host_class;
2083
2084        err = transport_class_register(&iscsi_session_class);
2085        if (err)
2086                goto unregister_conn_class;
2087
2088        nls = netlink_kernel_create(&init_net, NETLINK_ISCSI, 1, iscsi_if_rx,
2089                                    NULL, THIS_MODULE);
2090        if (!nls) {
2091                err = -ENOBUFS;
2092                goto unregister_session_class;
2093        }
2094
2095        iscsi_eh_timer_workq = create_singlethread_workqueue("iscsi_eh");
2096        if (!iscsi_eh_timer_workq)
2097                goto release_nls;
2098
2099        return 0;
2100
2101release_nls:
2102        netlink_kernel_release(nls);
2103unregister_session_class:
2104        transport_class_unregister(&iscsi_session_class);
2105unregister_conn_class:
2106        transport_class_unregister(&iscsi_connection_class);
2107unregister_host_class:
2108        transport_class_unregister(&iscsi_host_class);
2109unregister_endpoint_class:
2110        class_unregister(&iscsi_endpoint_class);
2111unregister_transport_class:
2112        class_unregister(&iscsi_transport_class);
2113        return err;
2114}
2115
2116static void __exit iscsi_transport_exit(void)
2117{
2118        destroy_workqueue(iscsi_eh_timer_workq);
2119        netlink_kernel_release(nls);
2120        transport_class_unregister(&iscsi_connection_class);
2121        transport_class_unregister(&iscsi_session_class);
2122        transport_class_unregister(&iscsi_host_class);
2123        class_unregister(&iscsi_endpoint_class);
2124        class_unregister(&iscsi_transport_class);
2125}
2126
2127module_init(iscsi_transport_init);
2128module_exit(iscsi_transport_exit);
2129
2130MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
2131              "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
2132              "Alex Aizman <itn780@yahoo.com>");
2133MODULE_DESCRIPTION("iSCSI Transport Interface");
2134MODULE_LICENSE("GPL");
2135MODULE_VERSION(ISCSI_TRANSPORT_VERSION);
2136
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