drivers/scsi/scsi_transport_iscsi.c

   1 /*
   2  * iSCSI transport class definitions
   3  *
   4  * Copyright (C) IBM Corporation, 2004
   5  * Copyright (C) Mike Christie, 2004 - 2005
   6  * Copyright (C) Dmitry Yusupov, 2004 - 2005
   7  * Copyright (C) Alex Aizman, 2004 - 2005
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  22  */
  23 #include <linux/module.h>
  24 #include <linux/mempool.h>
  25 #include <linux/mutex.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 11
  35 #define ISCSI_CONN_ATTRS 11
  36 #define ISCSI_HOST_ATTRS 0
  37
  38 struct iscsi_internal {
  39         int daemon_pid;
  40         struct scsi_transport_template t;
  41         struct iscsi_transport *iscsi_transport;
  42         struct list_head list;
  43         struct class_device cdev;
  44
  45         struct class_device_attribute *host_attrs[ISCSI_HOST_ATTRS + 1];
  46         struct transport_container conn_cont;
  47         struct class_device_attribute *conn_attrs[ISCSI_CONN_ATTRS + 1];
  48         struct transport_container session_cont;
  49         struct class_device_attribute *session_attrs[ISCSI_SESSION_ATTRS + 1];
  50 };
  51
  52 static int iscsi_session_nr;    /* sysfs session id for next new session */
  53
  54 /*
  55  * list of registered transports and lock that must
  56  * be held while accessing list. The iscsi_transport_lock must
  57  * be acquired after the rx_queue_mutex.
  58  */
  59 static LIST_HEAD(iscsi_transports);
  60 static DEFINE_SPINLOCK(iscsi_transport_lock);
  61
  62 #define to_iscsi_internal(tmpl) \
  63         container_of(tmpl, struct iscsi_internal, t)
  64
  65 #define cdev_to_iscsi_internal(_cdev) \
  66         container_of(_cdev, struct iscsi_internal, cdev)
  67
  68 static void iscsi_transport_release(struct class_device *cdev)
  69 {
  70         struct iscsi_internal *priv = cdev_to_iscsi_internal(cdev);
  71         kfree(priv);
  72 }
  73
  74 /*
  75  * iscsi_transport_class represents the iscsi_transports that are
  76  * registered.
  77  */
  78 static struct class iscsi_transport_class = {
  79         .name = "iscsi_transport",
  80         .release = iscsi_transport_release,
  81 };
  82
  83 static ssize_t
  84 show_transport_handle(struct class_device *cdev, char *buf)
  85 {
  86         struct iscsi_internal *priv = cdev_to_iscsi_internal(cdev);
  87         return sprintf(buf, "%llu\n", (unsigned long long)iscsi_handle(priv->iscsi_transport));
  88 }
  89 static CLASS_DEVICE_ATTR(handle, S_IRUGO, show_transport_handle, NULL);
  90
  91 #define show_transport_attr(name, format)                               \
  92 static ssize_t                                                          \
  93 show_transport_##name(struct class_device *cdev, char *buf)             \
  94 {                                                                       \
  95         struct iscsi_internal *priv = cdev_to_iscsi_internal(cdev);     \
  96         return sprintf(buf, format"\n", priv->iscsi_transport->name);   \
  97 }                                                                       \
  98 static CLASS_DEVICE_ATTR(name, S_IRUGO, show_transport_##name, NULL);
  99
 100 show_transport_attr(caps, "0x%x");
 101 show_transport_attr(max_lun, "%d");
 102 show_transport_attr(max_conn, "%d");
 103 show_transport_attr(max_cmd_len, "%d");
 104
 105 static struct attribute *iscsi_transport_attrs[] = {
 106         &class_device_attr_handle.attr,
 107         &class_device_attr_caps.attr,
 108         &class_device_attr_max_lun.attr,
 109         &class_device_attr_max_conn.attr,
 110         &class_device_attr_max_cmd_len.attr,
 111         NULL,
 112 };
 113
 114 static struct attribute_group iscsi_transport_group = {
 115         .attrs = iscsi_transport_attrs,
 116 };
 117
 118 static int iscsi_setup_host(struct transport_container *tc, struct device *dev,
 119                             struct class_device *cdev)
 120 {
 121         struct Scsi_Host *shost = dev_to_shost(dev);
 122         struct iscsi_host *ihost = shost->shost_data;
 123
 124         memset(ihost, 0, sizeof(*ihost));
 125         INIT_LIST_HEAD(&ihost->sessions);
 126         mutex_init(&ihost->mutex);
 127         return 0;
 128 }
 129
 130 static DECLARE_TRANSPORT_CLASS(iscsi_host_class,
 131                                "iscsi_host",
 132                                iscsi_setup_host,
 133                                NULL,
 134                                NULL);
 135
 136 static DECLARE_TRANSPORT_CLASS(iscsi_session_class,
 137                                "iscsi_session",
 138                                NULL,
 139                                NULL,
 140                                NULL);
 141
 142 static DECLARE_TRANSPORT_CLASS(iscsi_connection_class,
 143                                "iscsi_connection",
 144                                NULL,
 145                                NULL,
 146                                NULL);
 147
 148 static struct sock *nls;
 149 static DEFINE_MUTEX(rx_queue_mutex);
 150
 151 struct mempool_zone {
 152         mempool_t *pool;
 153         atomic_t allocated;
 154         int size;
 155         int hiwat;
 156         struct list_head freequeue;
 157         spinlock_t freelock;
 158 };
 159
 160 static struct mempool_zone *z_reply;
 161
 162 /*
 163  * Z_MAX_* - actual mempool size allocated at the mempool_zone_init() time
 164  * Z_HIWAT_* - zone's high watermark when if_error bit will be set to -ENOMEM
 165  *             so daemon will notice OOM on NETLINK tranposrt level and will
 166  *             be able to predict or change operational behavior
 167  */
 168 #define Z_MAX_REPLY     8
 169 #define Z_HIWAT_REPLY   6
 170 #define Z_MAX_PDU       8
 171 #define Z_HIWAT_PDU     6
 172 #define Z_MAX_ERROR     16
 173 #define Z_HIWAT_ERROR   12
 174
 175 static LIST_HEAD(sesslist);
 176 static DEFINE_SPINLOCK(sesslock);
 177 static LIST_HEAD(connlist);
 178 static DEFINE_SPINLOCK(connlock);
 179
 180 static uint32_t iscsi_conn_get_sid(struct iscsi_cls_conn *conn)
 181 {
 182         struct iscsi_cls_session *sess = iscsi_dev_to_session(conn->dev.parent);
 183         return sess->sid;
 184 }
 185
 186 /*
 187  * Returns the matching session to a given sid
 188  */
 189 static struct iscsi_cls_session *iscsi_session_lookup(uint32_t sid)
 190 {
 191         unsigned long flags;
 192         struct iscsi_cls_session *sess;
 193
 194         spin_lock_irqsave(&sesslock, flags);
 195         list_for_each_entry(sess, &sesslist, sess_list) {
 196                 if (sess->sid == sid) {
 197                         spin_unlock_irqrestore(&sesslock, flags);
 198                         return sess;
 199                 }
 200         }
 201         spin_unlock_irqrestore(&sesslock, flags);
 202         return NULL;
 203 }
 204
 205 /*
 206  * Returns the matching connection to a given sid / cid tuple
 207  */
 208 static struct iscsi_cls_conn *iscsi_conn_lookup(uint32_t sid, uint32_t cid)
 209 {
 210         unsigned long flags;
 211         struct iscsi_cls_conn *conn;
 212
 213         spin_lock_irqsave(&connlock, flags);
 214         list_for_each_entry(conn, &connlist, conn_list) {
 215                 if ((conn->cid == cid) && (iscsi_conn_get_sid(conn) == sid)) {
 216                         spin_unlock_irqrestore(&connlock, flags);
 217                         return conn;
 218                 }
 219         }
 220         spin_unlock_irqrestore(&connlock, flags);
 221         return NULL;
 222 }
 223
 224 /*
 225  * The following functions can be used by LLDs that allocate
 226  * their own scsi_hosts or by software iscsi LLDs
 227  */
 228 static void iscsi_session_release(struct device *dev)
 229 {
 230         struct iscsi_cls_session *session = iscsi_dev_to_session(dev);
 231         struct Scsi_Host *shost;
 232
 233         shost = iscsi_session_to_shost(session);
 234         scsi_host_put(shost);
 235         kfree(session);
 236 }
 237
 238 static int iscsi_is_session_dev(const struct device *dev)
 239 {
 240         return dev->release == iscsi_session_release;
 241 }
 242
 243 static int iscsi_user_scan(struct Scsi_Host *shost, uint channel,
 244                            uint id, uint lun)
 245 {
 246         struct iscsi_host *ihost = shost->shost_data;
 247         struct iscsi_cls_session *session;
 248
 249         mutex_lock(&ihost->mutex);
 250         list_for_each_entry(session, &ihost->sessions, host_list) {
 251                 if ((channel == SCAN_WILD_CARD ||
 252                      channel == session->channel) &&
 253                     (id == SCAN_WILD_CARD || id == session->target_id))
 254                         scsi_scan_target(&session->dev, session->channel,
 255                                          session->target_id, lun, 1);
 256         }
 257         mutex_unlock(&ihost->mutex);
 258
 259         return 0;
 260 }
 261
 262 static void session_recovery_timedout(void *data)
 263 {
 264         struct iscsi_cls_session *session = data;
 265
 266         dev_printk(KERN_INFO, &session->dev, "iscsi: session recovery timed "
 267                   "out after %d secs\n", session->recovery_tmo);
 268
 269         if (session->transport->session_recovery_timedout)
 270                 session->transport->session_recovery_timedout(session);
 271
 272         scsi_target_unblock(&session->dev);
 273 }
 274
 275 void iscsi_unblock_session(struct iscsi_cls_session *session)
 276 {
 277         if (!cancel_delayed_work(&session->recovery_work))
 278                 flush_scheduled_work();
 279         scsi_target_unblock(&session->dev);
 280 }
 281 EXPORT_SYMBOL_GPL(iscsi_unblock_session);
 282
 283 void iscsi_block_session(struct iscsi_cls_session *session)
 284 {
 285         scsi_target_block(&session->dev);
 286         schedule_delayed_work(&session->recovery_work,
 287                              session->recovery_tmo * HZ);
 288 }
 289 EXPORT_SYMBOL_GPL(iscsi_block_session);
 290
 291 /**
 292  * iscsi_create_session - create iscsi class session
 293  * @shost: scsi host
 294  * @transport: iscsi transport
 295  *
 296  * This can be called from a LLD or iscsi_transport.
 297  **/
 298 struct iscsi_cls_session *
 299 iscsi_create_session(struct Scsi_Host *shost,
 300                      struct iscsi_transport *transport, int channel)
 301 {
 302         struct iscsi_host *ihost;
 303         struct iscsi_cls_session *session;
 304         int err;
 305
 306         session = kzalloc(sizeof(*session) + transport->sessiondata_size,
 307                           GFP_KERNEL);
 308         if (!session)
 309                 return NULL;
 310
 311         session->transport = transport;
 312         session->recovery_tmo = 120;
 313         INIT_WORK(&session->recovery_work, session_recovery_timedout, session);
 314         INIT_LIST_HEAD(&session->host_list);
 315         INIT_LIST_HEAD(&session->sess_list);
 316
 317         if (transport->sessiondata_size)
 318                 session->dd_data = &session[1];
 319
 320         /* this is released in the dev's release function */
 321         scsi_host_get(shost);
 322         ihost = shost->shost_data;
 323
 324         session->sid = iscsi_session_nr++;
 325         session->channel = channel;
 326         session->target_id = ihost->next_target_id++;
 327
 328         snprintf(session->dev.bus_id, BUS_ID_SIZE, "session%u",
 329                  session->sid);
 330         session->dev.parent = &shost->shost_gendev;
 331         session->dev.release = iscsi_session_release;
 332         err = device_register(&session->dev);
 333         if (err) {
 334                 dev_printk(KERN_ERR, &session->dev, "iscsi: could not "
 335                            "register session's dev\n");
 336                 goto free_session;
 337         }
 338         transport_register_device(&session->dev);
 339
 340         mutex_lock(&ihost->mutex);
 341         list_add(&session->host_list, &ihost->sessions);
 342         mutex_unlock(&ihost->mutex);
 343
 344         return session;
 345
 346 free_session:
 347         kfree(session);
 348         return NULL;
 349 }
 350
 351 EXPORT_SYMBOL_GPL(iscsi_create_session);
 352
 353 /**
 354  * iscsi_destroy_session - destroy iscsi session
 355  * @session: iscsi_session
 356  *
 357  * Can be called by a LLD or iscsi_transport. There must not be
 358  * any running connections.
 359  **/
 360 int iscsi_destroy_session(struct iscsi_cls_session *session)
 361 {
 362         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 363         struct iscsi_host *ihost = shost->shost_data;
 364
 365         if (!cancel_delayed_work(&session->recovery_work))
 366                 flush_scheduled_work();
 367
 368         mutex_lock(&ihost->mutex);
 369         list_del(&session->host_list);
 370         mutex_unlock(&ihost->mutex);
 371
 372         transport_unregister_device(&session->dev);
 373         device_unregister(&session->dev);
 374         return 0;
 375 }
 376
 377 EXPORT_SYMBOL_GPL(iscsi_destroy_session);
 378
 379 static void iscsi_conn_release(struct device *dev)
 380 {
 381         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev);
 382         struct device *parent = conn->dev.parent;
 383
 384         kfree(conn);
 385         put_device(parent);
 386 }
 387
 388 static int iscsi_is_conn_dev(const struct device *dev)
 389 {
 390         return dev->release == iscsi_conn_release;
 391 }
 392
 393 /**
 394  * iscsi_create_conn - create iscsi class connection
 395  * @session: iscsi cls session
 396  * @cid: connection id
 397  *
 398  * This can be called from a LLD or iscsi_transport. The connection
 399  * is child of the session so cid must be unique for all connections
 400  * on the session.
 401  *
 402  * Since we do not support MCS, cid will normally be zero. In some cases
 403  * for software iscsi we could be trying to preallocate a connection struct
 404  * in which case there could be two connection structs and cid would be
 405  * non-zero.
 406  **/
 407 struct iscsi_cls_conn *
 408 iscsi_create_conn(struct iscsi_cls_session *session, uint32_t cid)
 409 {
 410         struct iscsi_transport *transport = session->transport;
 411         struct iscsi_cls_conn *conn;
 412         int err;
 413
 414         conn = kzalloc(sizeof(*conn) + transport->conndata_size, GFP_KERNEL);
 415         if (!conn)
 416                 return NULL;
 417
 418         if (transport->conndata_size)
 419                 conn->dd_data = &conn[1];
 420
 421         INIT_LIST_HEAD(&conn->conn_list);
 422         conn->transport = transport;
 423         conn->cid = cid;
 424
 425         /* this is released in the dev's release function */
 426         if (!get_device(&session->dev))
 427                 goto free_conn;
 428
 429         snprintf(conn->dev.bus_id, BUS_ID_SIZE, "connection%d:%u",
 430                  session->sid, cid);
 431         conn->dev.parent = &session->dev;
 432         conn->dev.release = iscsi_conn_release;
 433         err = device_register(&conn->dev);
 434         if (err) {
 435                 dev_printk(KERN_ERR, &conn->dev, "iscsi: could not register "
 436                            "connection's dev\n");
 437                 goto release_parent_ref;
 438         }
 439         transport_register_device(&conn->dev);
 440         return conn;
 441
 442 release_parent_ref:
 443         put_device(&session->dev);
 444 free_conn:
 445         kfree(conn);
 446         return NULL;
 447 }
 448
 449 EXPORT_SYMBOL_GPL(iscsi_create_conn);
 450
 451 /**
 452  * iscsi_destroy_conn - destroy iscsi class connection
 453  * @session: iscsi cls session
 454  *
 455  * This can be called from a LLD or iscsi_transport.
 456  **/
 457 int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
 458 {
 459         transport_unregister_device(&conn->dev);
 460         device_unregister(&conn->dev);
 461         return 0;
 462 }
 463
 464 EXPORT_SYMBOL_GPL(iscsi_destroy_conn);
 465
 466 /*
 467  * iscsi interface functions
 468  */
 469 static struct iscsi_internal *
 470 iscsi_if_transport_lookup(struct iscsi_transport *tt)
 471 {
 472         struct iscsi_internal *priv;
 473         unsigned long flags;
 474
 475         spin_lock_irqsave(&iscsi_transport_lock, flags);
 476         list_for_each_entry(priv, &iscsi_transports, list) {
 477                 if (tt == priv->iscsi_transport) {
 478                         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 479                         return priv;
 480                 }
 481         }
 482         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 483         return NULL;
 484 }
 485
 486 static inline struct list_head *skb_to_lh(struct sk_buff *skb)
 487 {
 488         return (struct list_head *)&skb->cb;
 489 }
 490
 491 static void*
 492 mempool_zone_alloc_skb(gfp_t gfp_mask, void *pool_data)
 493 {
 494         struct mempool_zone *zone = pool_data;
 495
 496         return alloc_skb(zone->size, gfp_mask);
 497 }
 498
 499 static void
 500 mempool_zone_free_skb(void *element, void *pool_data)
 501 {
 502         kfree_skb(element);
 503 }
 504
 505 static void
 506 mempool_zone_complete(struct mempool_zone *zone)
 507 {
 508         unsigned long flags;
 509         struct list_head *lh, *n;
 510
 511         spin_lock_irqsave(&zone->freelock, flags);
 512         list_for_each_safe(lh, n, &zone->freequeue) {
 513                 struct sk_buff *skb = (struct sk_buff *)((char *)lh -
 514                                 offsetof(struct sk_buff, cb));
 515                 if (!skb_shared(skb)) {
 516                         list_del(skb_to_lh(skb));
 517                         mempool_free(skb, zone->pool);
 518                         atomic_dec(&zone->allocated);
 519                 }
 520         }
 521         spin_unlock_irqrestore(&zone->freelock, flags);
 522 }
 523
 524 static struct mempool_zone *
 525 mempool_zone_init(unsigned max, unsigned size, unsigned hiwat)
 526 {
 527         struct mempool_zone *zp;
 528
 529         zp = kzalloc(sizeof(*zp), GFP_KERNEL);
 530         if (!zp)
 531                 return NULL;
 532
 533         zp->size = size;
 534         zp->hiwat = hiwat;
 535         INIT_LIST_HEAD(&zp->freequeue);
 536         spin_lock_init(&zp->freelock);
 537         atomic_set(&zp->allocated, 0);
 538
 539         zp->pool = mempool_create(max, mempool_zone_alloc_skb,
 540                                   mempool_zone_free_skb, zp);
 541         if (!zp->pool) {
 542                 kfree(zp);
 543                 return NULL;
 544         }
 545
 546         return zp;
 547 }
 548
 549 static void mempool_zone_destroy(struct mempool_zone *zp)
 550 {
 551         mempool_destroy(zp->pool);
 552         kfree(zp);
 553 }
 554
 555 static struct sk_buff*
 556 mempool_zone_get_skb(struct mempool_zone *zone)
 557 {
 558         struct sk_buff *skb;
 559
 560         skb = mempool_alloc(zone->pool, GFP_ATOMIC);
 561         if (skb)
 562                 atomic_inc(&zone->allocated);
 563         return skb;
 564 }
 565
 566 static int
 567 iscsi_unicast_skb(struct mempool_zone *zone, struct sk_buff *skb, int pid)
 568 {
 569         unsigned long flags;
 570         int rc;
 571
 572         skb_get(skb);
 573         rc = netlink_unicast(nls, skb, pid, MSG_DONTWAIT);
 574         if (rc < 0) {
 575                 mempool_free(skb, zone->pool);
 576                 printk(KERN_ERR "iscsi: can not unicast skb (%d)\n", rc);
 577                 return rc;
 578         }
 579
 580         spin_lock_irqsave(&zone->freelock, flags);
 581         INIT_LIST_HEAD(skb_to_lh(skb));
 582         list_add(skb_to_lh(skb), &zone->freequeue);
 583         spin_unlock_irqrestore(&zone->freelock, flags);
 584
 585         return 0;
 586 }
 587
 588 int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
 589                    char *data, uint32_t data_size)
 590 {
 591         struct nlmsghdr *nlh;
 592         struct sk_buff *skb;
 593         struct iscsi_uevent *ev;
 594         char *pdu;
 595         struct iscsi_internal *priv;
 596         int len = NLMSG_SPACE(sizeof(*ev) + sizeof(struct iscsi_hdr) +
 597                               data_size);
 598
 599         priv = iscsi_if_transport_lookup(conn->transport);
 600         if (!priv)
 601                 return -EINVAL;
 602
 603         mempool_zone_complete(conn->z_pdu);
 604
 605         skb = mempool_zone_get_skb(conn->z_pdu);
 606         if (!skb) {
 607                 iscsi_conn_error(conn, ISCSI_ERR_CONN_FAILED);
 608                 dev_printk(KERN_ERR, &conn->dev, "iscsi: can not deliver "
 609                            "control PDU: OOM\n");
 610                 return -ENOMEM;
 611         }
 612
 613         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
 614         ev = NLMSG_DATA(nlh);
 615         memset(ev, 0, sizeof(*ev));
 616         ev->transport_handle = iscsi_handle(conn->transport);
 617         ev->type = ISCSI_KEVENT_RECV_PDU;
 618         if (atomic_read(&conn->z_pdu->allocated) >= conn->z_pdu->hiwat)
 619                 ev->iferror = -ENOMEM;
 620         ev->r.recv_req.cid = conn->cid;
 621         ev->r.recv_req.sid = iscsi_conn_get_sid(conn);
 622         pdu = (char*)ev + sizeof(*ev);
 623         memcpy(pdu, hdr, sizeof(struct iscsi_hdr));
 624         memcpy(pdu + sizeof(struct iscsi_hdr), data, data_size);
 625
 626         return iscsi_unicast_skb(conn->z_pdu, skb, priv->daemon_pid);
 627 }
 628 EXPORT_SYMBOL_GPL(iscsi_recv_pdu);
 629
 630 void iscsi_conn_error(struct iscsi_cls_conn *conn, enum iscsi_err error)
 631 {
 632         struct nlmsghdr *nlh;
 633         struct sk_buff  *skb;
 634         struct iscsi_uevent *ev;
 635         struct iscsi_internal *priv;
 636         int len = NLMSG_SPACE(sizeof(*ev));
 637
 638         priv = iscsi_if_transport_lookup(conn->transport);
 639         if (!priv)
 640                 return;
 641
 642         mempool_zone_complete(conn->z_error);
 643
 644         skb = mempool_zone_get_skb(conn->z_error);
 645         if (!skb) {
 646                 dev_printk(KERN_ERR, &conn->dev, "iscsi: gracefully ignored "
 647                           "conn error (%d)\n", error);
 648                 return;
 649         }
 650
 651         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
 652         ev = NLMSG_DATA(nlh);
 653         ev->transport_handle = iscsi_handle(conn->transport);
 654         ev->type = ISCSI_KEVENT_CONN_ERROR;
 655         if (atomic_read(&conn->z_error->allocated) >= conn->z_error->hiwat)
 656                 ev->iferror = -ENOMEM;
 657         ev->r.connerror.error = error;
 658         ev->r.connerror.cid = conn->cid;
 659         ev->r.connerror.sid = iscsi_conn_get_sid(conn);
 660
 661         iscsi_unicast_skb(conn->z_error, skb, priv->daemon_pid);
 662
 663         dev_printk(KERN_INFO, &conn->dev, "iscsi: detected conn error (%d)\n",
 664                    error);
 665 }
 666 EXPORT_SYMBOL_GPL(iscsi_conn_error);
 667
 668 static int
 669 iscsi_if_send_reply(int pid, int seq, int type, int done, int multi,
 670                       void *payload, int size)
 671 {
 672         struct sk_buff  *skb;
 673         struct nlmsghdr *nlh;
 674         int len = NLMSG_SPACE(size);
 675         int flags = multi ? NLM_F_MULTI : 0;
 676         int t = done ? NLMSG_DONE : type;
 677
 678         mempool_zone_complete(z_reply);
 679
 680         skb = mempool_zone_get_skb(z_reply);
 681         /*
 682          * FIXME:
 683          * user is supposed to react on iferror == -ENOMEM;
 684          * see iscsi_if_rx().
 685          */
 686         BUG_ON(!skb);
 687
 688         nlh = __nlmsg_put(skb, pid, seq, t, (len - sizeof(*nlh)), 0);
 689         nlh->nlmsg_flags = flags;
 690         memcpy(NLMSG_DATA(nlh), payload, size);
 691         return iscsi_unicast_skb(z_reply, skb, pid);
 692 }
 693
 694 static int
 695 iscsi_if_get_stats(struct iscsi_transport *transport, struct nlmsghdr *nlh)
 696 {
 697         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
 698         struct iscsi_stats *stats;
 699         struct sk_buff *skbstat;
 700         struct iscsi_cls_conn *conn;
 701         struct nlmsghdr *nlhstat;
 702         struct iscsi_uevent *evstat;
 703         struct iscsi_internal *priv;
 704         int len = NLMSG_SPACE(sizeof(*ev) +
 705                               sizeof(struct iscsi_stats) +
 706                               sizeof(struct iscsi_stats_custom) *
 707                               ISCSI_STATS_CUSTOM_MAX);
 708         int err = 0;
 709
 710         priv = iscsi_if_transport_lookup(transport);
 711         if (!priv)
 712                 return -EINVAL;
 713
 714         conn = iscsi_conn_lookup(ev->u.get_stats.sid, ev->u.get_stats.cid);
 715         if (!conn)
 716                 return -EEXIST;
 717
 718         do {
 719                 int actual_size;
 720
 721                 mempool_zone_complete(conn->z_pdu);
 722
 723                 skbstat = mempool_zone_get_skb(conn->z_pdu);
 724                 if (!skbstat) {
 725                         dev_printk(KERN_ERR, &conn->dev, "iscsi: can not "
 726                                    "deliver stats: OOM\n");
 727                         return -ENOMEM;
 728                 }
 729
 730                 nlhstat = __nlmsg_put(skbstat, priv->daemon_pid, 0, 0,
 731                                       (len - sizeof(*nlhstat)), 0);
 732                 evstat = NLMSG_DATA(nlhstat);
 733                 memset(evstat, 0, sizeof(*evstat));
 734                 evstat->transport_handle = iscsi_handle(conn->transport);
 735                 evstat->type = nlh->nlmsg_type;
 736                 if (atomic_read(&conn->z_pdu->allocated) >= conn->z_pdu->hiwat)
 737                         evstat->iferror = -ENOMEM;
 738                 evstat->u.get_stats.cid =
 739                         ev->u.get_stats.cid;
 740                 evstat->u.get_stats.sid =
 741                         ev->u.get_stats.sid;
 742                 stats = (struct iscsi_stats *)
 743                         ((char*)evstat + sizeof(*evstat));
 744                 memset(stats, 0, sizeof(*stats));
 745
 746                 transport->get_stats(conn, stats);
 747                 actual_size = NLMSG_SPACE(sizeof(struct iscsi_uevent) +
 748                                           sizeof(struct iscsi_stats) +
 749                                           sizeof(struct iscsi_stats_custom) *
 750                                           stats->custom_length);
 751                 actual_size -= sizeof(*nlhstat);
 752                 actual_size = NLMSG_LENGTH(actual_size);
 753                 skb_trim(skbstat, NLMSG_ALIGN(actual_size));
 754                 nlhstat->nlmsg_len = actual_size;
 755
 756                 err = iscsi_unicast_skb(conn->z_pdu, skbstat, priv->daemon_pid);
 757         } while (err < 0 && err != -ECONNREFUSED);
 758
 759         return err;
 760 }
 761
 762 static int
 763 iscsi_if_create_session(struct iscsi_internal *priv, struct iscsi_uevent *ev)
 764 {
 765         struct iscsi_transport *transport = priv->iscsi_transport;
 766         struct iscsi_cls_session *session;
 767         unsigned long flags;
 768         uint32_t hostno;
 769
 770         session = transport->create_session(transport, &priv->t,
 771                                             ev->u.c_session.initial_cmdsn,
 772                                             &hostno);
 773         if (!session)
 774                 return -ENOMEM;
 775
 776         spin_lock_irqsave(&sesslock, flags);
 777         list_add(&session->sess_list, &sesslist);
 778         spin_unlock_irqrestore(&sesslock, flags);
 779
 780         ev->r.c_session_ret.host_no = hostno;
 781         ev->r.c_session_ret.sid = session->sid;
 782         return 0;
 783 }
 784
 785 static int
 786 iscsi_if_create_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
 787 {
 788         struct iscsi_cls_conn *conn;
 789         struct iscsi_cls_session *session;
 790         unsigned long flags;
 791
 792         session = iscsi_session_lookup(ev->u.c_conn.sid);
 793         if (!session) {
 794                 printk(KERN_ERR "iscsi: invalid session %d\n",
 795                        ev->u.c_conn.sid);
 796                 return -EINVAL;
 797         }
 798
 799         conn = transport->create_conn(session, ev->u.c_conn.cid);
 800         if (!conn) {
 801                 printk(KERN_ERR "iscsi: couldn't create a new "
 802                            "connection for session %d\n",
 803                            session->sid);
 804                 return -ENOMEM;
 805         }
 806
 807         conn->z_pdu = mempool_zone_init(Z_MAX_PDU,
 808                         NLMSG_SPACE(sizeof(struct iscsi_uevent) +
 809                                     sizeof(struct iscsi_hdr) +
 810                                     DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH),
 811                         Z_HIWAT_PDU);
 812         if (!conn->z_pdu) {
 813                 dev_printk(KERN_ERR, &conn->dev, "iscsi: can not allocate "
 814                            "pdu zone for new conn\n");
 815                 goto destroy_conn;
 816         }
 817
 818         conn->z_error = mempool_zone_init(Z_MAX_ERROR,
 819                         NLMSG_SPACE(sizeof(struct iscsi_uevent)),
 820                         Z_HIWAT_ERROR);
 821         if (!conn->z_error) {
 822                 dev_printk(KERN_ERR, &conn->dev, "iscsi: can not allocate "
 823                            "error zone for new conn\n");
 824                 goto free_pdu_pool;
 825         }
 826
 827         ev->r.c_conn_ret.sid = session->sid;
 828         ev->r.c_conn_ret.cid = conn->cid;
 829
 830         spin_lock_irqsave(&connlock, flags);
 831         list_add(&conn->conn_list, &connlist);
 832         conn->active = 1;
 833         spin_unlock_irqrestore(&connlock, flags);
 834
 835         return 0;
 836
 837 free_pdu_pool:
 838         mempool_zone_destroy(conn->z_pdu);
 839 destroy_conn:
 840         if (transport->destroy_conn)
 841                 transport->destroy_conn(conn->dd_data);
 842         return -ENOMEM;
 843 }
 844
 845 static int
 846 iscsi_if_destroy_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
 847 {
 848         unsigned long flags;
 849         struct iscsi_cls_conn *conn;
 850         struct mempool_zone *z_error, *z_pdu;
 851
 852         conn = iscsi_conn_lookup(ev->u.d_conn.sid, ev->u.d_conn.cid);
 853         if (!conn)
 854                 return -EINVAL;
 855         spin_lock_irqsave(&connlock, flags);
 856         conn->active = 0;
 857         list_del(&conn->conn_list);
 858         spin_unlock_irqrestore(&connlock, flags);
 859
 860         z_pdu = conn->z_pdu;
 861         z_error = conn->z_error;
 862
 863         if (transport->destroy_conn)
 864                 transport->destroy_conn(conn);
 865
 866         mempool_zone_destroy(z_pdu);
 867         mempool_zone_destroy(z_error);
 868
 869         return 0;
 870 }
 871
 872 static int
 873 iscsi_set_param(struct iscsi_transport *transport, struct iscsi_uevent *ev)
 874 {
 875         char *data = (char*)ev + sizeof(*ev);
 876         struct iscsi_cls_conn *conn;
 877         struct iscsi_cls_session *session;
 878         int err = 0, value = 0;
 879
 880         session = iscsi_session_lookup(ev->u.set_param.sid);
 881         conn = iscsi_conn_lookup(ev->u.set_param.sid, ev->u.set_param.cid);
 882         if (!conn || !session)
 883                 return -EINVAL;
 884
 885         switch (ev->u.set_param.param) {
 886         case ISCSI_PARAM_SESS_RECOVERY_TMO:
 887                 sscanf(data, "%d", &value);
 888                 if (value != 0)
 889                         session->recovery_tmo = value;
 890                 break;
 891         default:
 892                 err = transport->set_param(conn, ev->u.set_param.param,
 893                                            data, ev->u.set_param.len);
 894         }
 895
 896         return err;
 897 }
 898
 899 static int
 900 iscsi_if_transport_ep(struct iscsi_transport *transport,
 901                       struct iscsi_uevent *ev, int msg_type)
 902 {
 903         struct sockaddr *dst_addr;
 904         int rc = 0;
 905
 906         switch (msg_type) {
 907         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
 908                 if (!transport->ep_connect)
 909                         return -EINVAL;
 910
 911                 dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
 912                 rc = transport->ep_connect(dst_addr,
 913                                            ev->u.ep_connect.non_blocking,
 914                                            &ev->r.ep_connect_ret.handle);
 915                 break;
 916         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
 917                 if (!transport->ep_poll)
 918                         return -EINVAL;
 919
 920                 ev->r.retcode = transport->ep_poll(ev->u.ep_poll.ep_handle,
 921                                                    ev->u.ep_poll.timeout_ms);
 922                 break;
 923         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
 924                 if (!transport->ep_disconnect)
 925                         return -EINVAL;
 926
 927                 transport->ep_disconnect(ev->u.ep_disconnect.ep_handle);
 928                 break;
 929         }
 930         return rc;
 931 }
 932
 933 static int
 934 iscsi_tgt_dscvr(struct iscsi_transport *transport,
 935                 struct iscsi_uevent *ev)
 936 {
 937         struct sockaddr *dst_addr;
 938
 939         if (!transport->tgt_dscvr)
 940                 return -EINVAL;
 941
 942         dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
 943         return transport->tgt_dscvr(ev->u.tgt_dscvr.type,
 944                                     ev->u.tgt_dscvr.host_no,
 945                                     ev->u.tgt_dscvr.enable, dst_addr);
 946 }
 947
 948 static int
 949 iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 950 {
 951         int err = 0;
 952         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
 953         struct iscsi_transport *transport = NULL;
 954         struct iscsi_internal *priv;
 955         struct iscsi_cls_session *session;
 956         struct iscsi_cls_conn *conn;
 957         unsigned long flags;
 958
 959         priv = iscsi_if_transport_lookup(iscsi_ptr(ev->transport_handle));
 960         if (!priv)
 961                 return -EINVAL;
 962         transport = priv->iscsi_transport;
 963
 964         if (!try_module_get(transport->owner))
 965                 return -EINVAL;
 966
 967         priv->daemon_pid = NETLINK_CREDS(skb)->pid;
 968
 969         switch (nlh->nlmsg_type) {
 970         case ISCSI_UEVENT_CREATE_SESSION:
 971                 err = iscsi_if_create_session(priv, ev);
 972                 break;
 973         case ISCSI_UEVENT_DESTROY_SESSION:
 974                 session = iscsi_session_lookup(ev->u.d_session.sid);
 975                 if (session) {
 976                         spin_lock_irqsave(&sesslock, flags);
 977                         list_del(&session->sess_list);
 978                         spin_unlock_irqrestore(&sesslock, flags);
 979
 980                         transport->destroy_session(session);
 981                 } else
 982                         err = -EINVAL;
 983                 break;
 984         case ISCSI_UEVENT_CREATE_CONN:
 985                 err = iscsi_if_create_conn(transport, ev);
 986                 break;
 987         case ISCSI_UEVENT_DESTROY_CONN:
 988                 err = iscsi_if_destroy_conn(transport, ev);
 989                 break;
 990         case ISCSI_UEVENT_BIND_CONN:
 991                 session = iscsi_session_lookup(ev->u.b_conn.sid);
 992                 conn = iscsi_conn_lookup(ev->u.b_conn.sid, ev->u.b_conn.cid);
 993
 994                 if (session && conn)
 995                         ev->r.retcode = transport->bind_conn(session, conn,
 996                                         ev->u.b_conn.transport_eph,
 997                                         ev->u.b_conn.is_leading);
 998                 else
 999                         err = -EINVAL;
1000                 break;
1001         case ISCSI_UEVENT_SET_PARAM:
1002                 err = iscsi_set_param(transport, ev);
1003                 break;
1004         case ISCSI_UEVENT_START_CONN:
1005                 conn = iscsi_conn_lookup(ev->u.start_conn.sid, ev->u.start_conn.cid);
1006                 if (conn)
1007                         ev->r.retcode = transport->start_conn(conn);
1008                 else
1009                         err = -EINVAL;
1010                 break;
1011         case ISCSI_UEVENT_STOP_CONN:
1012                 conn = iscsi_conn_lookup(ev->u.stop_conn.sid, ev->u.stop_conn.cid);
1013                 if (conn)
1014                         transport->stop_conn(conn, ev->u.stop_conn.flag);
1015                 else
1016                         err = -EINVAL;
1017                 break;
1018         case ISCSI_UEVENT_SEND_PDU:
1019                 conn = iscsi_conn_lookup(ev->u.send_pdu.sid, ev->u.send_pdu.cid);
1020                 if (conn)
1021                         ev->r.retcode = transport->send_pdu(conn,
1022                                 (struct iscsi_hdr*)((char*)ev + sizeof(*ev)),
1023                                 (char*)ev + sizeof(*ev) + ev->u.send_pdu.hdr_size,
1024                                 ev->u.send_pdu.data_size);
1025                 else
1026                         err = -EINVAL;
1027                 break;
1028         case ISCSI_UEVENT_GET_STATS:
1029                 err = iscsi_if_get_stats(transport, nlh);
1030                 break;
1031         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1032         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1033         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1034                 err = iscsi_if_transport_ep(transport, ev, nlh->nlmsg_type);
1035                 break;
1036         case ISCSI_UEVENT_TGT_DSCVR:
1037                 err = iscsi_tgt_dscvr(transport, ev);
1038                 break;
1039         default:
1040                 err = -EINVAL;
1041                 break;
1042         }
1043
1044         module_put(transport->owner);
1045         return err;
1046 }
1047
1048 /*
1049  * Get message from skb (based on rtnetlink_rcv_skb).  Each message is
1050  * processed by iscsi_if_recv_msg.  Malformed skbs with wrong lengths or
1051  * invalid creds are discarded silently.
1052  */
1053 static void
1054 iscsi_if_rx(struct sock *sk, int len)
1055 {
1056         struct sk_buff *skb;
1057
1058         mutex_lock(&rx_queue_mutex);
1059         while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
1060                 if (NETLINK_CREDS(skb)->uid) {
1061                         skb_pull(skb, skb->len);
1062                         goto free_skb;
1063                 }
1064
1065                 while (skb->len >= NLMSG_SPACE(0)) {
1066                         int err;
1067                         uint32_t rlen;
1068                         struct nlmsghdr *nlh;
1069                         struct iscsi_uevent *ev;
1070
1071                         nlh = (struct nlmsghdr *)skb->data;
1072                         if (nlh->nlmsg_len < sizeof(*nlh) ||
1073                             skb->len < nlh->nlmsg_len) {
1074                                 break;
1075                         }
1076
1077                         ev = NLMSG_DATA(nlh);
1078                         rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1079                         if (rlen > skb->len)
1080                                 rlen = skb->len;
1081
1082                         err = iscsi_if_recv_msg(skb, nlh);
1083                         if (err) {
1084                                 ev->type = ISCSI_KEVENT_IF_ERROR;
1085                                 ev->iferror = err;
1086                         }
1087                         do {
1088                                 /*
1089                                  * special case for GET_STATS:
1090                                  * on success - sending reply and stats from
1091                                  * inside of if_recv_msg(),
1092                                  * on error - fall through.
1093                                  */
1094                                 if (ev->type == ISCSI_UEVENT_GET_STATS && !err)
1095                                         break;
1096                                 err = iscsi_if_send_reply(
1097                                         NETLINK_CREDS(skb)->pid, nlh->nlmsg_seq,
1098                                         nlh->nlmsg_type, 0, 0, ev, sizeof(*ev));
1099                                 if (atomic_read(&z_reply->allocated) >=
1100                                                 z_reply->hiwat)
1101                                         ev->iferror = -ENOMEM;
1102                         } while (err < 0 && err != -ECONNREFUSED);
1103                         skb_pull(skb, rlen);
1104                 }
1105 free_skb:
1106                 kfree_skb(skb);
1107         }
1108         mutex_unlock(&rx_queue_mutex);
1109 }
1110
1111 #define iscsi_cdev_to_conn(_cdev) \
1112         iscsi_dev_to_conn(_cdev->dev)
1113
1114 #define ISCSI_CLASS_ATTR(_prefix,_name,_mode,_show,_store)              \
1115 struct class_device_attribute class_device_attr_##_prefix##_##_name =   \
1116         __ATTR(_name,_mode,_show,_store)
1117
1118 /*
1119  * iSCSI connection attrs
1120  */
1121 #define iscsi_conn_attr_show(param)                                     \
1122 static ssize_t                                                          \
1123 show_conn_param_##param(struct class_device *cdev, char *buf)           \
1124 {                                                                       \
1125         struct iscsi_cls_conn *conn = iscsi_cdev_to_conn(cdev);         \
1126         struct iscsi_transport *t = conn->transport;                    \
1127         return t->get_conn_param(conn, param, buf);                     \
1128 }
1129
1130 #define iscsi_conn_attr(field, param)                                   \
1131         iscsi_conn_attr_show(param)                                     \
1132 static ISCSI_CLASS_ATTR(conn, field, S_IRUGO, show_conn_param_##param,  \
1133                         NULL);
1134
1135 iscsi_conn_attr(max_recv_dlength, ISCSI_PARAM_MAX_RECV_DLENGTH);
1136 iscsi_conn_attr(max_xmit_dlength, ISCSI_PARAM_MAX_XMIT_DLENGTH);
1137 iscsi_conn_attr(header_digest, ISCSI_PARAM_HDRDGST_EN);
1138 iscsi_conn_attr(data_digest, ISCSI_PARAM_DATADGST_EN);
1139 iscsi_conn_attr(ifmarker, ISCSI_PARAM_IFMARKER_EN);
1140 iscsi_conn_attr(ofmarker, ISCSI_PARAM_OFMARKER_EN);
1141 iscsi_conn_attr(persistent_port, ISCSI_PARAM_PERSISTENT_PORT);
1142 iscsi_conn_attr(port, ISCSI_PARAM_CONN_PORT);
1143 iscsi_conn_attr(exp_statsn, ISCSI_PARAM_EXP_STATSN);
1144 iscsi_conn_attr(persistent_address, ISCSI_PARAM_PERSISTENT_ADDRESS);
1145 iscsi_conn_attr(address, ISCSI_PARAM_CONN_ADDRESS);
1146
1147 #define iscsi_cdev_to_session(_cdev) \
1148         iscsi_dev_to_session(_cdev->dev)
1149
1150 /*
1151  * iSCSI session attrs
1152  */
1153 #define iscsi_session_attr_show(param)                                  \
1154 static ssize_t                                                          \
1155 show_session_param_##param(struct class_device *cdev, char *buf)        \
1156 {                                                                       \
1157         struct iscsi_cls_session *session = iscsi_cdev_to_session(cdev); \
1158         struct iscsi_transport *t = session->transport;                 \
1159         return t->get_session_param(session, param, buf);               \
1160 }
1161
1162 #define iscsi_session_attr(field, param)                                \
1163         iscsi_session_attr_show(param)                                  \
1164 static ISCSI_CLASS_ATTR(sess, field, S_IRUGO, show_session_param_##param, \
1165                         NULL);
1166
1167 iscsi_session_attr(targetname, ISCSI_PARAM_TARGET_NAME);
1168 iscsi_session_attr(initial_r2t, ISCSI_PARAM_INITIAL_R2T_EN);
1169 iscsi_session_attr(max_outstanding_r2t, ISCSI_PARAM_MAX_R2T);
1170 iscsi_session_attr(immediate_data, ISCSI_PARAM_IMM_DATA_EN);
1171 iscsi_session_attr(first_burst_len, ISCSI_PARAM_FIRST_BURST);
1172 iscsi_session_attr(max_burst_len, ISCSI_PARAM_MAX_BURST);
1173 iscsi_session_attr(data_pdu_in_order, ISCSI_PARAM_PDU_INORDER_EN);
1174 iscsi_session_attr(data_seq_in_order, ISCSI_PARAM_DATASEQ_INORDER_EN);
1175 iscsi_session_attr(erl, ISCSI_PARAM_ERL);
1176 iscsi_session_attr(tpgt, ISCSI_PARAM_TPGT);
1177
1178 #define iscsi_priv_session_attr_show(field, format)                     \
1179 static ssize_t                                                          \
1180 show_priv_session_##field(struct class_device *cdev, char *buf)         \
1181 {                                                                       \
1182         struct iscsi_cls_session *session = iscsi_cdev_to_session(cdev);\
1183         return sprintf(buf, format"\n", session->field);                \
1184 }
1185
1186 #define iscsi_priv_session_attr(field, format)                          \
1187         iscsi_priv_session_attr_show(field, format)                     \
1188 static ISCSI_CLASS_ATTR(priv_sess, field, S_IRUGO, show_priv_session_##field, \
1189                         NULL)
1190 iscsi_priv_session_attr(recovery_tmo, "%d");
1191
1192 #define SETUP_PRIV_SESSION_RD_ATTR(field)                               \
1193 do {                                                                    \
1194         priv->session_attrs[count] = &class_device_attr_priv_sess_##field; \
1195         count++;                                                        \
1196 } while (0)
1197
1198
1199 #define SETUP_SESSION_RD_ATTR(field, param_flag)                        \
1200 do {                                                                    \
1201         if (tt->param_mask & param_flag) {                              \
1202                 priv->session_attrs[count] = &class_device_attr_sess_##field; \
1203                 count++;                                                \
1204         }                                                               \
1205 } while (0)
1206
1207 #define SETUP_CONN_RD_ATTR(field, param_flag)                           \
1208 do {                                                                    \
1209         if (tt->param_mask & param_flag) {                              \
1210                 priv->conn_attrs[count] = &class_device_attr_conn_##field; \
1211                 count++;                                                \
1212         }                                                               \
1213 } while (0)
1214
1215 static int iscsi_session_match(struct attribute_container *cont,
1216                            struct device *dev)
1217 {
1218         struct iscsi_cls_session *session;
1219         struct Scsi_Host *shost;
1220         struct iscsi_internal *priv;
1221
1222         if (!iscsi_is_session_dev(dev))
1223                 return 0;
1224
1225         session = iscsi_dev_to_session(dev);
1226         shost = iscsi_session_to_shost(session);
1227         if (!shost->transportt)
1228                 return 0;
1229
1230         priv = to_iscsi_internal(shost->transportt);
1231         if (priv->session_cont.ac.class != &iscsi_session_class.class)
1232                 return 0;
1233
1234         return &priv->session_cont.ac == cont;
1235 }
1236
1237 static int iscsi_conn_match(struct attribute_container *cont,
1238                            struct device *dev)
1239 {
1240         struct iscsi_cls_session *session;
1241         struct iscsi_cls_conn *conn;
1242         struct Scsi_Host *shost;
1243         struct iscsi_internal *priv;
1244
1245         if (!iscsi_is_conn_dev(dev))
1246                 return 0;
1247
1248         conn = iscsi_dev_to_conn(dev);
1249         session = iscsi_dev_to_session(conn->dev.parent);
1250         shost = iscsi_session_to_shost(session);
1251
1252         if (!shost->transportt)
1253                 return 0;
1254
1255         priv = to_iscsi_internal(shost->transportt);
1256         if (priv->conn_cont.ac.class != &iscsi_connection_class.class)
1257                 return 0;
1258
1259         return &priv->conn_cont.ac == cont;
1260 }
1261
1262 static int iscsi_host_match(struct attribute_container *cont,
1263                             struct device *dev)
1264 {
1265         struct Scsi_Host *shost;
1266         struct iscsi_internal *priv;
1267
1268         if (!scsi_is_host_device(dev))
1269                 return 0;
1270
1271         shost = dev_to_shost(dev);
1272         if (!shost->transportt  ||
1273             shost->transportt->host_attrs.ac.class != &iscsi_host_class.class)
1274                 return 0;
1275
1276         priv = to_iscsi_internal(shost->transportt);
1277         return &priv->t.host_attrs.ac == cont;
1278 }
1279
1280 struct scsi_transport_template *
1281 iscsi_register_transport(struct iscsi_transport *tt)
1282 {
1283         struct iscsi_internal *priv;
1284         unsigned long flags;
1285         int count = 0, err;
1286
1287         BUG_ON(!tt);
1288
1289         priv = iscsi_if_transport_lookup(tt);
1290         if (priv)
1291                 return NULL;
1292
1293         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1294         if (!priv)
1295                 return NULL;
1296         INIT_LIST_HEAD(&priv->list);
1297         priv->iscsi_transport = tt;
1298         priv->t.user_scan = iscsi_user_scan;
1299
1300         priv->cdev.class = &iscsi_transport_class;
1301         snprintf(priv->cdev.class_id, BUS_ID_SIZE, "%s", tt->name);
1302         err = class_device_register(&priv->cdev);
1303         if (err)
1304                 goto free_priv;
1305
1306         err = sysfs_create_group(&priv->cdev.kobj, &iscsi_transport_group);
1307         if (err)
1308                 goto unregister_cdev;
1309
1310         /* host parameters */
1311         priv->t.host_attrs.ac.attrs = &priv->host_attrs[0];
1312         priv->t.host_attrs.ac.class = &iscsi_host_class.class;
1313         priv->t.host_attrs.ac.match = iscsi_host_match;
1314         priv->t.host_size = sizeof(struct iscsi_host);
1315         priv->host_attrs[0] = NULL;
1316         transport_container_register(&priv->t.host_attrs);
1317
1318         /* connection parameters */
1319         priv->conn_cont.ac.attrs = &priv->conn_attrs[0];
1320         priv->conn_cont.ac.class = &iscsi_connection_class.class;
1321         priv->conn_cont.ac.match = iscsi_conn_match;
1322         transport_container_register(&priv->conn_cont);
1323
1324         SETUP_CONN_RD_ATTR(max_recv_dlength, ISCSI_MAX_RECV_DLENGTH);
1325         SETUP_CONN_RD_ATTR(max_xmit_dlength, ISCSI_MAX_XMIT_DLENGTH);
1326         SETUP_CONN_RD_ATTR(header_digest, ISCSI_HDRDGST_EN);
1327         SETUP_CONN_RD_ATTR(data_digest, ISCSI_DATADGST_EN);
1328         SETUP_CONN_RD_ATTR(ifmarker, ISCSI_IFMARKER_EN);
1329         SETUP_CONN_RD_ATTR(ofmarker, ISCSI_OFMARKER_EN);
1330         SETUP_CONN_RD_ATTR(address, ISCSI_CONN_ADDRESS);
1331         SETUP_CONN_RD_ATTR(port, ISCSI_CONN_PORT);
1332         SETUP_CONN_RD_ATTR(exp_statsn, ISCSI_EXP_STATSN);
1333         SETUP_CONN_RD_ATTR(persistent_address, ISCSI_PERSISTENT_ADDRESS);
1334         SETUP_CONN_RD_ATTR(persistent_port, ISCSI_PERSISTENT_PORT);
1335
1336         BUG_ON(count > ISCSI_CONN_ATTRS);
1337         priv->conn_attrs[count] = NULL;
1338         count = 0;
1339
1340         /* session parameters */
1341         priv->session_cont.ac.attrs = &priv->session_attrs[0];
1342         priv->session_cont.ac.class = &iscsi_session_class.class;
1343         priv->session_cont.ac.match = iscsi_session_match;
1344         transport_container_register(&priv->session_cont);
1345
1346         SETUP_SESSION_RD_ATTR(initial_r2t, ISCSI_INITIAL_R2T_EN);
1347         SETUP_SESSION_RD_ATTR(max_outstanding_r2t, ISCSI_MAX_R2T);
1348         SETUP_SESSION_RD_ATTR(immediate_data, ISCSI_IMM_DATA_EN);
1349         SETUP_SESSION_RD_ATTR(first_burst_len, ISCSI_FIRST_BURST);
1350         SETUP_SESSION_RD_ATTR(max_burst_len, ISCSI_MAX_BURST);
1351         SETUP_SESSION_RD_ATTR(data_pdu_in_order, ISCSI_PDU_INORDER_EN);
1352         SETUP_SESSION_RD_ATTR(data_seq_in_order, ISCSI_DATASEQ_INORDER_EN);
1353         SETUP_SESSION_RD_ATTR(erl, ISCSI_ERL);
1354         SETUP_SESSION_RD_ATTR(targetname, ISCSI_TARGET_NAME);
1355         SETUP_SESSION_RD_ATTR(tpgt, ISCSI_TPGT);
1356         SETUP_PRIV_SESSION_RD_ATTR(recovery_tmo);
1357
1358         BUG_ON(count > ISCSI_SESSION_ATTRS);
1359         priv->session_attrs[count] = NULL;
1360
1361         spin_lock_irqsave(&iscsi_transport_lock, flags);
1362         list_add(&priv->list, &iscsi_transports);
1363         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1364
1365         printk(KERN_NOTICE "iscsi: registered transport (%s)\n", tt->name);
1366         return &priv->t;
1367
1368 unregister_cdev:
1369         class_device_unregister(&priv->cdev);
1370 free_priv:
1371         kfree(priv);
1372         return NULL;
1373 }
1374 EXPORT_SYMBOL_GPL(iscsi_register_transport);
1375
1376 int iscsi_unregister_transport(struct iscsi_transport *tt)
1377 {
1378         struct iscsi_internal *priv;
1379         unsigned long flags;
1380
1381         BUG_ON(!tt);
1382
1383         mutex_lock(&rx_queue_mutex);
1384
1385         priv = iscsi_if_transport_lookup(tt);
1386         BUG_ON (!priv);
1387
1388         spin_lock_irqsave(&iscsi_transport_lock, flags);
1389         list_del(&priv->list);
1390         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1391
1392         transport_container_unregister(&priv->conn_cont);
1393         transport_container_unregister(&priv->session_cont);
1394         transport_container_unregister(&priv->t.host_attrs);
1395
1396         sysfs_remove_group(&priv->cdev.kobj, &iscsi_transport_group);
1397         class_device_unregister(&priv->cdev);
1398         mutex_unlock(&rx_queue_mutex);
1399
1400         return 0;
1401 }
1402 EXPORT_SYMBOL_GPL(iscsi_unregister_transport);
1403
1404 static int
1405 iscsi_rcv_nl_event(struct notifier_block *this, unsigned long event, void *ptr)
1406 {
1407         struct netlink_notify *n = ptr;
1408
1409         if (event == NETLINK_URELEASE &&
1410             n->protocol == NETLINK_ISCSI && n->pid) {
1411                 struct iscsi_cls_conn *conn;
1412                 unsigned long flags;
1413
1414                 mempool_zone_complete(z_reply);
1415                 spin_lock_irqsave(&connlock, flags);
1416                 list_for_each_entry(conn, &connlist, conn_list) {
1417                         mempool_zone_complete(conn->z_error);
1418                         mempool_zone_complete(conn->z_pdu);
1419                 }
1420                 spin_unlock_irqrestore(&connlock, flags);
1421         }
1422
1423         return NOTIFY_DONE;
1424 }
1425
1426 static struct notifier_block iscsi_nl_notifier = {
1427         .notifier_call  = iscsi_rcv_nl_event,
1428 };
1429
1430 static __init int iscsi_transport_init(void)
1431 {
1432         int err;
1433
1434         err = class_register(&iscsi_transport_class);
1435         if (err)
1436                 return err;
1437
1438         err = transport_class_register(&iscsi_host_class);
1439         if (err)
1440                 goto unregister_transport_class;
1441
1442         err = transport_class_register(&iscsi_connection_class);
1443         if (err)
1444                 goto unregister_host_class;
1445
1446         err = transport_class_register(&iscsi_session_class);
1447         if (err)
1448                 goto unregister_conn_class;
1449
1450         err = netlink_register_notifier(&iscsi_nl_notifier);
1451         if (err)
1452                 goto unregister_session_class;
1453
1454         nls = netlink_kernel_create(NETLINK_ISCSI, 1, iscsi_if_rx,
1455                         THIS_MODULE);
1456         if (!nls) {
1457                 err = -ENOBUFS;
1458                 goto unregister_notifier;
1459         }
1460
1461         z_reply = mempool_zone_init(Z_MAX_REPLY,
1462                 NLMSG_SPACE(sizeof(struct iscsi_uevent)), Z_HIWAT_REPLY);
1463         if (z_reply)
1464                 return 0;
1465
1466         sock_release(nls->sk_socket);
1467 unregister_notifier:
1468         netlink_unregister_notifier(&iscsi_nl_notifier);
1469 unregister_session_class:
1470         transport_class_unregister(&iscsi_session_class);
1471 unregister_conn_class:
1472         transport_class_unregister(&iscsi_connection_class);
1473 unregister_host_class:
1474         transport_class_unregister(&iscsi_host_class);
1475 unregister_transport_class:
1476         class_unregister(&iscsi_transport_class);
1477         return err;
1478 }
1479
1480 static void __exit iscsi_transport_exit(void)
1481 {
1482         mempool_zone_destroy(z_reply);
1483         sock_release(nls->sk_socket);
1484         netlink_unregister_notifier(&iscsi_nl_notifier);
1485         transport_class_unregister(&iscsi_connection_class);
1486         transport_class_unregister(&iscsi_session_class);
1487         transport_class_unregister(&iscsi_host_class);
1488         class_unregister(&iscsi_transport_class);
1489 }
1490
1491 module_init(iscsi_transport_init);
1492 module_exit(iscsi_transport_exit);
1493
1494 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
1495               "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
1496               "Alex Aizman <itn780@yahoo.com>");
1497 MODULE_DESCRIPTION("iSCSI Transport Interface");
1498 MODULE_LICENSE("GPL");