drivers/scsi/scsi_transport_iscsi.c

   1 /*
   2  * iSCSI transport class definitions
   3  *
   4  * Copyright (C) IBM Corporation, 2004
   5  * Copyright (C) Mike Christie, 2004 - 2005
   6  * Copyright (C) Dmitry Yusupov, 2004 - 2005
   7  * Copyright (C) Alex Aizman, 2004 - 2005
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  22  */
  23 #include <linux/module.h>
  24 #include <linux/mutex.h>
  25 #include <net/tcp.h>
  26 #include <scsi/scsi.h>
  27 #include <scsi/scsi_host.h>
  28 #include <scsi/scsi_device.h>
  29 #include <scsi/scsi_transport.h>
  30 #include <scsi/scsi_transport_iscsi.h>
  31 #include <scsi/iscsi_if.h>
  32
  33 #define ISCSI_SESSION_ATTRS 11
  34 #define ISCSI_CONN_ATTRS 11
  35 #define ISCSI_HOST_ATTRS 0
  36 #define ISCSI_TRANSPORT_VERSION "2.0-724"
  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 static LIST_HEAD(sesslist);
 152 static DEFINE_SPINLOCK(sesslock);
 153 static LIST_HEAD(connlist);
 154 static DEFINE_SPINLOCK(connlock);
 155
 156 static uint32_t iscsi_conn_get_sid(struct iscsi_cls_conn *conn)
 157 {
 158         struct iscsi_cls_session *sess = iscsi_dev_to_session(conn->dev.parent);
 159         return sess->sid;
 160 }
 161
 162 /*
 163  * Returns the matching session to a given sid
 164  */
 165 static struct iscsi_cls_session *iscsi_session_lookup(uint32_t sid)
 166 {
 167         unsigned long flags;
 168         struct iscsi_cls_session *sess;
 169
 170         spin_lock_irqsave(&sesslock, flags);
 171         list_for_each_entry(sess, &sesslist, sess_list) {
 172                 if (sess->sid == sid) {
 173                         spin_unlock_irqrestore(&sesslock, flags);
 174                         return sess;
 175                 }
 176         }
 177         spin_unlock_irqrestore(&sesslock, flags);
 178         return NULL;
 179 }
 180
 181 /*
 182  * Returns the matching connection to a given sid / cid tuple
 183  */
 184 static struct iscsi_cls_conn *iscsi_conn_lookup(uint32_t sid, uint32_t cid)
 185 {
 186         unsigned long flags;
 187         struct iscsi_cls_conn *conn;
 188
 189         spin_lock_irqsave(&connlock, flags);
 190         list_for_each_entry(conn, &connlist, conn_list) {
 191                 if ((conn->cid == cid) && (iscsi_conn_get_sid(conn) == sid)) {
 192                         spin_unlock_irqrestore(&connlock, flags);
 193                         return conn;
 194                 }
 195         }
 196         spin_unlock_irqrestore(&connlock, flags);
 197         return NULL;
 198 }
 199
 200 /*
 201  * The following functions can be used by LLDs that allocate
 202  * their own scsi_hosts or by software iscsi LLDs
 203  */
 204 static void iscsi_session_release(struct device *dev)
 205 {
 206         struct iscsi_cls_session *session = iscsi_dev_to_session(dev);
 207         struct Scsi_Host *shost;
 208
 209         shost = iscsi_session_to_shost(session);
 210         scsi_host_put(shost);
 211         kfree(session);
 212 }
 213
 214 static int iscsi_is_session_dev(const struct device *dev)
 215 {
 216         return dev->release == iscsi_session_release;
 217 }
 218
 219 static int iscsi_user_scan(struct Scsi_Host *shost, uint channel,
 220                            uint id, uint lun)
 221 {
 222         struct iscsi_host *ihost = shost->shost_data;
 223         struct iscsi_cls_session *session;
 224
 225         mutex_lock(&ihost->mutex);
 226         list_for_each_entry(session, &ihost->sessions, host_list) {
 227                 if ((channel == SCAN_WILD_CARD || channel == 0) &&
 228                     (id == SCAN_WILD_CARD || id == session->target_id))
 229                         scsi_scan_target(&session->dev, 0,
 230                                          session->target_id, lun, 1);
 231         }
 232         mutex_unlock(&ihost->mutex);
 233
 234         return 0;
 235 }
 236
 237 static void session_recovery_timedout(void *data)
 238 {
 239         struct iscsi_cls_session *session = data;
 240
 241         dev_printk(KERN_INFO, &session->dev, "iscsi: session recovery timed "
 242                   "out after %d secs\n", session->recovery_tmo);
 243
 244         if (session->transport->session_recovery_timedout)
 245                 session->transport->session_recovery_timedout(session);
 246
 247         scsi_target_unblock(&session->dev);
 248 }
 249
 250 void iscsi_unblock_session(struct iscsi_cls_session *session)
 251 {
 252         if (!cancel_delayed_work(&session->recovery_work))
 253                 flush_scheduled_work();
 254         scsi_target_unblock(&session->dev);
 255 }
 256 EXPORT_SYMBOL_GPL(iscsi_unblock_session);
 257
 258 void iscsi_block_session(struct iscsi_cls_session *session)
 259 {
 260         scsi_target_block(&session->dev);
 261         schedule_delayed_work(&session->recovery_work,
 262                              session->recovery_tmo * HZ);
 263 }
 264 EXPORT_SYMBOL_GPL(iscsi_block_session);
 265
 266 struct iscsi_cls_session *
 267 iscsi_alloc_session(struct Scsi_Host *shost,
 268                     struct iscsi_transport *transport)
 269 {
 270         struct iscsi_cls_session *session;
 271
 272         session = kzalloc(sizeof(*session) + transport->sessiondata_size,
 273                           GFP_KERNEL);
 274         if (!session)
 275                 return NULL;
 276
 277         session->transport = transport;
 278         session->recovery_tmo = 120;
 279         INIT_WORK(&session->recovery_work, session_recovery_timedout, session);
 280         INIT_LIST_HEAD(&session->host_list);
 281         INIT_LIST_HEAD(&session->sess_list);
 282
 283         /* this is released in the dev's release function */
 284         scsi_host_get(shost);
 285         session->dev.parent = &shost->shost_gendev;
 286         session->dev.release = iscsi_session_release;
 287         device_initialize(&session->dev);
 288         if (transport->sessiondata_size)
 289                 session->dd_data = &session[1];
 290         return session;
 291 }
 292 EXPORT_SYMBOL_GPL(iscsi_alloc_session);
 293
 294 int iscsi_add_session(struct iscsi_cls_session *session, unsigned int target_id)
 295 {
 296         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 297         struct iscsi_host *ihost;
 298         int err;
 299
 300         ihost = shost->shost_data;
 301         session->sid = iscsi_session_nr++;
 302         session->target_id = target_id;
 303
 304         snprintf(session->dev.bus_id, BUS_ID_SIZE, "session%u",
 305                  session->sid);
 306         err = device_add(&session->dev);
 307         if (err) {
 308                 dev_printk(KERN_ERR, &session->dev, "iscsi: could not "
 309                            "register session's dev\n");
 310                 goto release_host;
 311         }
 312         transport_register_device(&session->dev);
 313
 314         mutex_lock(&ihost->mutex);
 315         list_add(&session->host_list, &ihost->sessions);
 316         mutex_unlock(&ihost->mutex);
 317         return 0;
 318
 319 release_host:
 320         scsi_host_put(shost);
 321         return err;
 322 }
 323 EXPORT_SYMBOL_GPL(iscsi_add_session);
 324
 325 /**
 326  * iscsi_create_session - create iscsi class session
 327  * @shost: scsi host
 328  * @transport: iscsi transport
 329  *
 330  * This can be called from a LLD or iscsi_transport.
 331  **/
 332 struct iscsi_cls_session *
 333 iscsi_create_session(struct Scsi_Host *shost,
 334                      struct iscsi_transport *transport,
 335                      unsigned int target_id)
 336 {
 337         struct iscsi_cls_session *session;
 338
 339         session = iscsi_alloc_session(shost, transport);
 340         if (!session)
 341                 return NULL;
 342
 343         if (iscsi_add_session(session, target_id)) {
 344                 iscsi_free_session(session);
 345                 return NULL;
 346         }
 347         return session;
 348 }
 349 EXPORT_SYMBOL_GPL(iscsi_create_session);
 350
 351 void iscsi_remove_session(struct iscsi_cls_session *session)
 352 {
 353         struct Scsi_Host *shost = iscsi_session_to_shost(session);
 354         struct iscsi_host *ihost = shost->shost_data;
 355
 356         if (!cancel_delayed_work(&session->recovery_work))
 357                 flush_scheduled_work();
 358
 359         mutex_lock(&ihost->mutex);
 360         list_del(&session->host_list);
 361         mutex_unlock(&ihost->mutex);
 362
 363         scsi_remove_target(&session->dev);
 364
 365         transport_unregister_device(&session->dev);
 366         device_del(&session->dev);
 367 }
 368 EXPORT_SYMBOL_GPL(iscsi_remove_session);
 369
 370 void iscsi_free_session(struct iscsi_cls_session *session)
 371 {
 372         put_device(&session->dev);
 373 }
 374
 375 EXPORT_SYMBOL_GPL(iscsi_free_session);
 376
 377 /**
 378  * iscsi_destroy_session - destroy iscsi session
 379  * @session: iscsi_session
 380  *
 381  * Can be called by a LLD or iscsi_transport. There must not be
 382  * any running connections.
 383  **/
 384 int iscsi_destroy_session(struct iscsi_cls_session *session)
 385 {
 386         iscsi_remove_session(session);
 387         iscsi_free_session(session);
 388         return 0;
 389 }
 390 EXPORT_SYMBOL_GPL(iscsi_destroy_session);
 391
 392 static void iscsi_conn_release(struct device *dev)
 393 {
 394         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev);
 395         struct device *parent = conn->dev.parent;
 396
 397         kfree(conn);
 398         put_device(parent);
 399 }
 400
 401 static int iscsi_is_conn_dev(const struct device *dev)
 402 {
 403         return dev->release == iscsi_conn_release;
 404 }
 405
 406 /**
 407  * iscsi_create_conn - create iscsi class connection
 408  * @session: iscsi cls session
 409  * @cid: connection id
 410  *
 411  * This can be called from a LLD or iscsi_transport. The connection
 412  * is child of the session so cid must be unique for all connections
 413  * on the session.
 414  *
 415  * Since we do not support MCS, cid will normally be zero. In some cases
 416  * for software iscsi we could be trying to preallocate a connection struct
 417  * in which case there could be two connection structs and cid would be
 418  * non-zero.
 419  **/
 420 struct iscsi_cls_conn *
 421 iscsi_create_conn(struct iscsi_cls_session *session, uint32_t cid)
 422 {
 423         struct iscsi_transport *transport = session->transport;
 424         struct iscsi_cls_conn *conn;
 425         int err;
 426
 427         conn = kzalloc(sizeof(*conn) + transport->conndata_size, GFP_KERNEL);
 428         if (!conn)
 429                 return NULL;
 430
 431         if (transport->conndata_size)
 432                 conn->dd_data = &conn[1];
 433
 434         INIT_LIST_HEAD(&conn->conn_list);
 435         conn->transport = transport;
 436         conn->cid = cid;
 437
 438         /* this is released in the dev's release function */
 439         if (!get_device(&session->dev))
 440                 goto free_conn;
 441
 442         snprintf(conn->dev.bus_id, BUS_ID_SIZE, "connection%d:%u",
 443                  session->sid, cid);
 444         conn->dev.parent = &session->dev;
 445         conn->dev.release = iscsi_conn_release;
 446         err = device_register(&conn->dev);
 447         if (err) {
 448                 dev_printk(KERN_ERR, &conn->dev, "iscsi: could not register "
 449                            "connection's dev\n");
 450                 goto release_parent_ref;
 451         }
 452         transport_register_device(&conn->dev);
 453         return conn;
 454
 455 release_parent_ref:
 456         put_device(&session->dev);
 457 free_conn:
 458         kfree(conn);
 459         return NULL;
 460 }
 461
 462 EXPORT_SYMBOL_GPL(iscsi_create_conn);
 463
 464 /**
 465  * iscsi_destroy_conn - destroy iscsi class connection
 466  * @session: iscsi cls session
 467  *
 468  * This can be called from a LLD or iscsi_transport.
 469  **/
 470 int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
 471 {
 472         transport_unregister_device(&conn->dev);
 473         device_unregister(&conn->dev);
 474         return 0;
 475 }
 476
 477 EXPORT_SYMBOL_GPL(iscsi_destroy_conn);
 478
 479 /*
 480  * iscsi interface functions
 481  */
 482 static struct iscsi_internal *
 483 iscsi_if_transport_lookup(struct iscsi_transport *tt)
 484 {
 485         struct iscsi_internal *priv;
 486         unsigned long flags;
 487
 488         spin_lock_irqsave(&iscsi_transport_lock, flags);
 489         list_for_each_entry(priv, &iscsi_transports, list) {
 490                 if (tt == priv->iscsi_transport) {
 491                         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 492                         return priv;
 493                 }
 494         }
 495         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 496         return NULL;
 497 }
 498
 499 static int
 500 iscsi_broadcast_skb(struct sk_buff *skb, gfp_t gfp)
 501 {
 502         int rc;
 503
 504         rc = netlink_broadcast(nls, skb, 0, 1, gfp);
 505         if (rc < 0) {
 506                 printk(KERN_ERR "iscsi: can not broadcast skb (%d)\n", rc);
 507                 return rc;
 508         }
 509
 510         return 0;
 511 }
 512
 513 static int
 514 iscsi_unicast_skb(struct sk_buff *skb, int pid)
 515 {
 516         int rc;
 517
 518         rc = netlink_unicast(nls, skb, pid, MSG_DONTWAIT);
 519         if (rc < 0) {
 520                 printk(KERN_ERR "iscsi: can not unicast skb (%d)\n", rc);
 521                 return rc;
 522         }
 523
 524         return 0;
 525 }
 526
 527 int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
 528                    char *data, uint32_t data_size)
 529 {
 530         struct nlmsghdr *nlh;
 531         struct sk_buff *skb;
 532         struct iscsi_uevent *ev;
 533         char *pdu;
 534         struct iscsi_internal *priv;
 535         int len = NLMSG_SPACE(sizeof(*ev) + sizeof(struct iscsi_hdr) +
 536                               data_size);
 537
 538         priv = iscsi_if_transport_lookup(conn->transport);
 539         if (!priv)
 540                 return -EINVAL;
 541
 542         skb = alloc_skb(len, GFP_ATOMIC);
 543         if (!skb) {
 544                 iscsi_conn_error(conn, ISCSI_ERR_CONN_FAILED);
 545                 dev_printk(KERN_ERR, &conn->dev, "iscsi: can not deliver "
 546                            "control PDU: OOM\n");
 547                 return -ENOMEM;
 548         }
 549
 550         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
 551         ev = NLMSG_DATA(nlh);
 552         memset(ev, 0, sizeof(*ev));
 553         ev->transport_handle = iscsi_handle(conn->transport);
 554         ev->type = ISCSI_KEVENT_RECV_PDU;
 555         ev->r.recv_req.cid = conn->cid;
 556         ev->r.recv_req.sid = iscsi_conn_get_sid(conn);
 557         pdu = (char*)ev + sizeof(*ev);
 558         memcpy(pdu, hdr, sizeof(struct iscsi_hdr));
 559         memcpy(pdu + sizeof(struct iscsi_hdr), data, data_size);
 560
 561         return iscsi_unicast_skb(skb, priv->daemon_pid);
 562 }
 563 EXPORT_SYMBOL_GPL(iscsi_recv_pdu);
 564
 565 void iscsi_conn_error(struct iscsi_cls_conn *conn, enum iscsi_err error)
 566 {
 567         struct nlmsghdr *nlh;
 568         struct sk_buff  *skb;
 569         struct iscsi_uevent *ev;
 570         struct iscsi_internal *priv;
 571         int len = NLMSG_SPACE(sizeof(*ev));
 572
 573         priv = iscsi_if_transport_lookup(conn->transport);
 574         if (!priv)
 575                 return;
 576
 577         skb = alloc_skb(len, GFP_ATOMIC);
 578         if (!skb) {
 579                 dev_printk(KERN_ERR, &conn->dev, "iscsi: gracefully ignored "
 580                           "conn error (%d)\n", error);
 581                 return;
 582         }
 583
 584         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
 585         ev = NLMSG_DATA(nlh);
 586         ev->transport_handle = iscsi_handle(conn->transport);
 587         ev->type = ISCSI_KEVENT_CONN_ERROR;
 588         ev->r.connerror.error = error;
 589         ev->r.connerror.cid = conn->cid;
 590         ev->r.connerror.sid = iscsi_conn_get_sid(conn);
 591
 592         iscsi_broadcast_skb(skb, GFP_ATOMIC);
 593
 594         dev_printk(KERN_INFO, &conn->dev, "iscsi: detected conn error (%d)\n",
 595                    error);
 596 }
 597 EXPORT_SYMBOL_GPL(iscsi_conn_error);
 598
 599 static int
 600 iscsi_if_send_reply(int pid, int seq, int type, int done, int multi,
 601                       void *payload, int size)
 602 {
 603         struct sk_buff  *skb;
 604         struct nlmsghdr *nlh;
 605         int len = NLMSG_SPACE(size);
 606         int flags = multi ? NLM_F_MULTI : 0;
 607         int t = done ? NLMSG_DONE : type;
 608
 609         skb = alloc_skb(len, GFP_ATOMIC);
 610         /*
 611          * FIXME:
 612          * user is supposed to react on iferror == -ENOMEM;
 613          * see iscsi_if_rx().
 614          */
 615         BUG_ON(!skb);
 616
 617         nlh = __nlmsg_put(skb, pid, seq, t, (len - sizeof(*nlh)), 0);
 618         nlh->nlmsg_flags = flags;
 619         memcpy(NLMSG_DATA(nlh), payload, size);
 620         return iscsi_unicast_skb(skb, pid);
 621 }
 622
 623 static int
 624 iscsi_if_get_stats(struct iscsi_transport *transport, struct nlmsghdr *nlh)
 625 {
 626         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
 627         struct iscsi_stats *stats;
 628         struct sk_buff *skbstat;
 629         struct iscsi_cls_conn *conn;
 630         struct nlmsghdr *nlhstat;
 631         struct iscsi_uevent *evstat;
 632         struct iscsi_internal *priv;
 633         int len = NLMSG_SPACE(sizeof(*ev) +
 634                               sizeof(struct iscsi_stats) +
 635                               sizeof(struct iscsi_stats_custom) *
 636                               ISCSI_STATS_CUSTOM_MAX);
 637         int err = 0;
 638
 639         priv = iscsi_if_transport_lookup(transport);
 640         if (!priv)
 641                 return -EINVAL;
 642
 643         conn = iscsi_conn_lookup(ev->u.get_stats.sid, ev->u.get_stats.cid);
 644         if (!conn)
 645                 return -EEXIST;
 646
 647         do {
 648                 int actual_size;
 649
 650                 skbstat = alloc_skb(len, GFP_ATOMIC);
 651                 if (!skbstat) {
 652                         dev_printk(KERN_ERR, &conn->dev, "iscsi: can not "
 653                                    "deliver stats: OOM\n");
 654                         return -ENOMEM;
 655                 }
 656
 657                 nlhstat = __nlmsg_put(skbstat, priv->daemon_pid, 0, 0,
 658                                       (len - sizeof(*nlhstat)), 0);
 659                 evstat = NLMSG_DATA(nlhstat);
 660                 memset(evstat, 0, sizeof(*evstat));
 661                 evstat->transport_handle = iscsi_handle(conn->transport);
 662                 evstat->type = nlh->nlmsg_type;
 663                 evstat->u.get_stats.cid =
 664                         ev->u.get_stats.cid;
 665                 evstat->u.get_stats.sid =
 666                         ev->u.get_stats.sid;
 667                 stats = (struct iscsi_stats *)
 668                         ((char*)evstat + sizeof(*evstat));
 669                 memset(stats, 0, sizeof(*stats));
 670
 671                 transport->get_stats(conn, stats);
 672                 actual_size = NLMSG_SPACE(sizeof(struct iscsi_uevent) +
 673                                           sizeof(struct iscsi_stats) +
 674                                           sizeof(struct iscsi_stats_custom) *
 675                                           stats->custom_length);
 676                 actual_size -= sizeof(*nlhstat);
 677                 actual_size = NLMSG_LENGTH(actual_size);
 678                 skb_trim(skbstat, NLMSG_ALIGN(actual_size));
 679                 nlhstat->nlmsg_len = actual_size;
 680
 681                 err = iscsi_unicast_skb(skbstat, priv->daemon_pid);
 682         } while (err < 0 && err != -ECONNREFUSED);
 683
 684         return err;
 685 }
 686
 687 /**
 688  * iscsi_if_destroy_session_done - send session destr. completion event
 689  * @conn: last connection for session
 690  *
 691  * This is called by HW iscsi LLDs to notify userpsace that its HW has
 692  * removed a session.
 693  **/
 694 int iscsi_if_destroy_session_done(struct iscsi_cls_conn *conn)
 695 {
 696         struct iscsi_internal *priv;
 697         struct iscsi_cls_session *session;
 698         struct Scsi_Host *shost;
 699         struct iscsi_uevent *ev;
 700         struct sk_buff  *skb;
 701         struct nlmsghdr *nlh;
 702         unsigned long flags;
 703         int rc, len = NLMSG_SPACE(sizeof(*ev));
 704
 705         priv = iscsi_if_transport_lookup(conn->transport);
 706         if (!priv)
 707                 return -EINVAL;
 708
 709         session = iscsi_dev_to_session(conn->dev.parent);
 710         shost = iscsi_session_to_shost(session);
 711
 712         skb = alloc_skb(len, GFP_KERNEL);
 713         if (!skb) {
 714                 dev_printk(KERN_ERR, &conn->dev, "Cannot notify userspace of "
 715                           "session creation event\n");
 716                 return -ENOMEM;
 717         }
 718
 719         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
 720         ev = NLMSG_DATA(nlh);
 721         ev->transport_handle = iscsi_handle(conn->transport);
 722         ev->type = ISCSI_KEVENT_DESTROY_SESSION;
 723         ev->r.d_session.host_no = shost->host_no;
 724         ev->r.d_session.sid = session->sid;
 725
 726         /*
 727          * this will occur if the daemon is not up, so we just warn
 728          * the user and when the daemon is restarted it will handle it
 729          */
 730         rc = iscsi_broadcast_skb(skb, GFP_KERNEL);
 731         if (rc < 0)
 732                 dev_printk(KERN_ERR, &conn->dev, "Cannot notify userspace of "
 733                           "session destruction event. Check iscsi daemon\n");
 734
 735         spin_lock_irqsave(&sesslock, flags);
 736         list_del(&session->sess_list);
 737         spin_unlock_irqrestore(&sesslock, flags);
 738
 739         spin_lock_irqsave(&connlock, flags);
 740         conn->active = 0;
 741         list_del(&conn->conn_list);
 742         spin_unlock_irqrestore(&connlock, flags);
 743
 744         return rc;
 745 }
 746 EXPORT_SYMBOL_GPL(iscsi_if_destroy_session_done);
 747
 748 /**
 749  * iscsi_if_create_session_done - send session creation completion event
 750  * @conn: leading connection for session
 751  *
 752  * This is called by HW iscsi LLDs to notify userpsace that its HW has
 753  * created a session or a existing session is back in the logged in state.
 754  **/
 755 int iscsi_if_create_session_done(struct iscsi_cls_conn *conn)
 756 {
 757         struct iscsi_internal *priv;
 758         struct iscsi_cls_session *session;
 759         struct Scsi_Host *shost;
 760         struct iscsi_uevent *ev;
 761         struct sk_buff  *skb;
 762         struct nlmsghdr *nlh;
 763         unsigned long flags;
 764         int rc, len = NLMSG_SPACE(sizeof(*ev));
 765
 766         priv = iscsi_if_transport_lookup(conn->transport);
 767         if (!priv)
 768                 return -EINVAL;
 769
 770         session = iscsi_dev_to_session(conn->dev.parent);
 771         shost = iscsi_session_to_shost(session);
 772
 773         skb = alloc_skb(len, GFP_KERNEL);
 774         if (!skb) {
 775                 dev_printk(KERN_ERR, &conn->dev, "Cannot notify userspace of "
 776                           "session creation event\n");
 777                 return -ENOMEM;
 778         }
 779
 780         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
 781         ev = NLMSG_DATA(nlh);
 782         ev->transport_handle = iscsi_handle(conn->transport);
 783         ev->type = ISCSI_UEVENT_CREATE_SESSION;
 784         ev->r.c_session_ret.host_no = shost->host_no;
 785         ev->r.c_session_ret.sid = session->sid;
 786
 787         /*
 788          * this will occur if the daemon is not up, so we just warn
 789          * the user and when the daemon is restarted it will handle it
 790          */
 791         rc = iscsi_broadcast_skb(skb, GFP_KERNEL);
 792         if (rc < 0)
 793                 dev_printk(KERN_ERR, &conn->dev, "Cannot notify userspace of "
 794                           "session creation event. Check iscsi daemon\n");
 795
 796         spin_lock_irqsave(&sesslock, flags);
 797         list_add(&session->sess_list, &sesslist);
 798         spin_unlock_irqrestore(&sesslock, flags);
 799
 800         spin_lock_irqsave(&connlock, flags);
 801         list_add(&conn->conn_list, &connlist);
 802         conn->active = 1;
 803         spin_unlock_irqrestore(&connlock, flags);
 804         return rc;
 805 }
 806 EXPORT_SYMBOL_GPL(iscsi_if_create_session_done);
 807
 808 static int
 809 iscsi_if_create_session(struct iscsi_internal *priv, struct iscsi_uevent *ev)
 810 {
 811         struct iscsi_transport *transport = priv->iscsi_transport;
 812         struct iscsi_cls_session *session;
 813         unsigned long flags;
 814         uint32_t hostno;
 815
 816         session = transport->create_session(transport, &priv->t,
 817                                             ev->u.c_session.initial_cmdsn,
 818                                             &hostno);
 819         if (!session)
 820                 return -ENOMEM;
 821
 822         spin_lock_irqsave(&sesslock, flags);
 823         list_add(&session->sess_list, &sesslist);
 824         spin_unlock_irqrestore(&sesslock, flags);
 825
 826         ev->r.c_session_ret.host_no = hostno;
 827         ev->r.c_session_ret.sid = session->sid;
 828         return 0;
 829 }
 830
 831 static int
 832 iscsi_if_create_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
 833 {
 834         struct iscsi_cls_conn *conn;
 835         struct iscsi_cls_session *session;
 836         unsigned long flags;
 837
 838         session = iscsi_session_lookup(ev->u.c_conn.sid);
 839         if (!session) {
 840                 printk(KERN_ERR "iscsi: invalid session %d\n",
 841                        ev->u.c_conn.sid);
 842                 return -EINVAL;
 843         }
 844
 845         conn = transport->create_conn(session, ev->u.c_conn.cid);
 846         if (!conn) {
 847                 printk(KERN_ERR "iscsi: couldn't create a new "
 848                            "connection for session %d\n",
 849                            session->sid);
 850                 return -ENOMEM;
 851         }
 852
 853         ev->r.c_conn_ret.sid = session->sid;
 854         ev->r.c_conn_ret.cid = conn->cid;
 855
 856         spin_lock_irqsave(&connlock, flags);
 857         list_add(&conn->conn_list, &connlist);
 858         conn->active = 1;
 859         spin_unlock_irqrestore(&connlock, flags);
 860
 861         return 0;
 862 }
 863
 864 static int
 865 iscsi_if_destroy_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
 866 {
 867         unsigned long flags;
 868         struct iscsi_cls_conn *conn;
 869
 870         conn = iscsi_conn_lookup(ev->u.d_conn.sid, ev->u.d_conn.cid);
 871         if (!conn)
 872                 return -EINVAL;
 873         spin_lock_irqsave(&connlock, flags);
 874         conn->active = 0;
 875         list_del(&conn->conn_list);
 876         spin_unlock_irqrestore(&connlock, flags);
 877
 878         if (transport->destroy_conn)
 879                 transport->destroy_conn(conn);
 880         return 0;
 881 }
 882
 883 static int
 884 iscsi_set_param(struct iscsi_transport *transport, struct iscsi_uevent *ev)
 885 {
 886         char *data = (char*)ev + sizeof(*ev);
 887         struct iscsi_cls_conn *conn;
 888         struct iscsi_cls_session *session;
 889         int err = 0, value = 0;
 890
 891         session = iscsi_session_lookup(ev->u.set_param.sid);
 892         conn = iscsi_conn_lookup(ev->u.set_param.sid, ev->u.set_param.cid);
 893         if (!conn || !session)
 894                 return -EINVAL;
 895
 896         switch (ev->u.set_param.param) {
 897         case ISCSI_PARAM_SESS_RECOVERY_TMO:
 898                 sscanf(data, "%d", &value);
 899                 if (value != 0)
 900                         session->recovery_tmo = value;
 901                 break;
 902         default:
 903                 err = transport->set_param(conn, ev->u.set_param.param,
 904                                            data, ev->u.set_param.len);
 905         }
 906
 907         return err;
 908 }
 909
 910 static int
 911 iscsi_if_transport_ep(struct iscsi_transport *transport,
 912                       struct iscsi_uevent *ev, int msg_type)
 913 {
 914         struct sockaddr *dst_addr;
 915         int rc = 0;
 916
 917         switch (msg_type) {
 918         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
 919                 if (!transport->ep_connect)
 920                         return -EINVAL;
 921
 922                 dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
 923                 rc = transport->ep_connect(dst_addr,
 924                                            ev->u.ep_connect.non_blocking,
 925                                            &ev->r.ep_connect_ret.handle);
 926                 break;
 927         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
 928                 if (!transport->ep_poll)
 929                         return -EINVAL;
 930
 931                 ev->r.retcode = transport->ep_poll(ev->u.ep_poll.ep_handle,
 932                                                    ev->u.ep_poll.timeout_ms);
 933                 break;
 934         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
 935                 if (!transport->ep_disconnect)
 936                         return -EINVAL;
 937
 938                 transport->ep_disconnect(ev->u.ep_disconnect.ep_handle);
 939                 break;
 940         }
 941         return rc;
 942 }
 943
 944 static int
 945 iscsi_tgt_dscvr(struct iscsi_transport *transport,
 946                 struct iscsi_uevent *ev)
 947 {
 948         struct sockaddr *dst_addr;
 949
 950         if (!transport->tgt_dscvr)
 951                 return -EINVAL;
 952
 953         dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
 954         return transport->tgt_dscvr(ev->u.tgt_dscvr.type,
 955                                     ev->u.tgt_dscvr.host_no,
 956                                     ev->u.tgt_dscvr.enable, dst_addr);
 957 }
 958
 959 static int
 960 iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 961 {
 962         int err = 0;
 963         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
 964         struct iscsi_transport *transport = NULL;
 965         struct iscsi_internal *priv;
 966         struct iscsi_cls_session *session;
 967         struct iscsi_cls_conn *conn;
 968         unsigned long flags;
 969
 970         priv = iscsi_if_transport_lookup(iscsi_ptr(ev->transport_handle));
 971         if (!priv)
 972                 return -EINVAL;
 973         transport = priv->iscsi_transport;
 974
 975         if (!try_module_get(transport->owner))
 976                 return -EINVAL;
 977
 978         priv->daemon_pid = NETLINK_CREDS(skb)->pid;
 979
 980         switch (nlh->nlmsg_type) {
 981         case ISCSI_UEVENT_CREATE_SESSION:
 982                 err = iscsi_if_create_session(priv, ev);
 983                 break;
 984         case ISCSI_UEVENT_DESTROY_SESSION:
 985                 session = iscsi_session_lookup(ev->u.d_session.sid);
 986                 if (session) {
 987                         spin_lock_irqsave(&sesslock, flags);
 988                         list_del(&session->sess_list);
 989                         spin_unlock_irqrestore(&sesslock, flags);
 990
 991                         transport->destroy_session(session);
 992                 } else
 993                         err = -EINVAL;
 994                 break;
 995         case ISCSI_UEVENT_CREATE_CONN:
 996                 err = iscsi_if_create_conn(transport, ev);
 997                 break;
 998         case ISCSI_UEVENT_DESTROY_CONN:
 999                 err = iscsi_if_destroy_conn(transport, ev);
1000                 break;
1001         case ISCSI_UEVENT_BIND_CONN:
1002                 session = iscsi_session_lookup(ev->u.b_conn.sid);
1003                 conn = iscsi_conn_lookup(ev->u.b_conn.sid, ev->u.b_conn.cid);
1004
1005                 if (session && conn)
1006                         ev->r.retcode = transport->bind_conn(session, conn,
1007                                         ev->u.b_conn.transport_eph,
1008                                         ev->u.b_conn.is_leading);
1009                 else
1010                         err = -EINVAL;
1011                 break;
1012         case ISCSI_UEVENT_SET_PARAM:
1013                 err = iscsi_set_param(transport, ev);
1014                 break;
1015         case ISCSI_UEVENT_START_CONN:
1016                 conn = iscsi_conn_lookup(ev->u.start_conn.sid, ev->u.start_conn.cid);
1017                 if (conn)
1018                         ev->r.retcode = transport->start_conn(conn);
1019                 else
1020                         err = -EINVAL;
1021                 break;
1022         case ISCSI_UEVENT_STOP_CONN:
1023                 conn = iscsi_conn_lookup(ev->u.stop_conn.sid, ev->u.stop_conn.cid);
1024                 if (conn)
1025                         transport->stop_conn(conn, ev->u.stop_conn.flag);
1026                 else
1027                         err = -EINVAL;
1028                 break;
1029         case ISCSI_UEVENT_SEND_PDU:
1030                 conn = iscsi_conn_lookup(ev->u.send_pdu.sid, ev->u.send_pdu.cid);
1031                 if (conn)
1032                         ev->r.retcode = transport->send_pdu(conn,
1033                                 (struct iscsi_hdr*)((char*)ev + sizeof(*ev)),
1034                                 (char*)ev + sizeof(*ev) + ev->u.send_pdu.hdr_size,
1035                                 ev->u.send_pdu.data_size);
1036                 else
1037                         err = -EINVAL;
1038                 break;
1039         case ISCSI_UEVENT_GET_STATS:
1040                 err = iscsi_if_get_stats(transport, nlh);
1041                 break;
1042         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1043         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1044         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1045                 err = iscsi_if_transport_ep(transport, ev, nlh->nlmsg_type);
1046                 break;
1047         case ISCSI_UEVENT_TGT_DSCVR:
1048                 err = iscsi_tgt_dscvr(transport, ev);
1049                 break;
1050         default:
1051                 err = -EINVAL;
1052                 break;
1053         }
1054
1055         module_put(transport->owner);
1056         return err;
1057 }
1058
1059 /*
1060  * Get message from skb (based on rtnetlink_rcv_skb).  Each message is
1061  * processed by iscsi_if_recv_msg.  Malformed skbs with wrong lengths or
1062  * invalid creds are discarded silently.
1063  */
1064 static void
1065 iscsi_if_rx(struct sock *sk, int len)
1066 {
1067         struct sk_buff *skb;
1068
1069         mutex_lock(&rx_queue_mutex);
1070         while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
1071                 if (NETLINK_CREDS(skb)->uid) {
1072                         skb_pull(skb, skb->len);
1073                         goto free_skb;
1074                 }
1075
1076                 while (skb->len >= NLMSG_SPACE(0)) {
1077                         int err;
1078                         uint32_t rlen;
1079                         struct nlmsghdr *nlh;
1080                         struct iscsi_uevent *ev;
1081
1082                         nlh = (struct nlmsghdr *)skb->data;
1083                         if (nlh->nlmsg_len < sizeof(*nlh) ||
1084                             skb->len < nlh->nlmsg_len) {
1085                                 break;
1086                         }
1087
1088                         ev = NLMSG_DATA(nlh);
1089                         rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1090                         if (rlen > skb->len)
1091                                 rlen = skb->len;
1092
1093                         err = iscsi_if_recv_msg(skb, nlh);
1094                         if (err) {
1095                                 ev->type = ISCSI_KEVENT_IF_ERROR;
1096                                 ev->iferror = err;
1097                         }
1098                         do {
1099                                 /*
1100                                  * special case for GET_STATS:
1101                                  * on success - sending reply and stats from
1102                                  * inside of if_recv_msg(),
1103                                  * on error - fall through.
1104                                  */
1105                                 if (ev->type == ISCSI_UEVENT_GET_STATS && !err)
1106                                         break;
1107                                 err = iscsi_if_send_reply(
1108                                         NETLINK_CREDS(skb)->pid, nlh->nlmsg_seq,
1109                                         nlh->nlmsg_type, 0, 0, ev, sizeof(*ev));
1110                         } while (err < 0 && err != -ECONNREFUSED);
1111                         skb_pull(skb, rlen);
1112                 }
1113 free_skb:
1114                 kfree_skb(skb);
1115         }
1116         mutex_unlock(&rx_queue_mutex);
1117 }
1118
1119 #define iscsi_cdev_to_conn(_cdev) \
1120         iscsi_dev_to_conn(_cdev->dev)
1121
1122 #define ISCSI_CLASS_ATTR(_prefix,_name,_mode,_show,_store)              \
1123 struct class_device_attribute class_device_attr_##_prefix##_##_name =   \
1124         __ATTR(_name,_mode,_show,_store)
1125
1126 /*
1127  * iSCSI connection attrs
1128  */
1129 #define iscsi_conn_attr_show(param)                                     \
1130 static ssize_t                                                          \
1131 show_conn_param_##param(struct class_device *cdev, char *buf)           \
1132 {                                                                       \
1133         struct iscsi_cls_conn *conn = iscsi_cdev_to_conn(cdev);         \
1134         struct iscsi_transport *t = conn->transport;                    \
1135         return t->get_conn_param(conn, param, buf);                     \
1136 }
1137
1138 #define iscsi_conn_attr(field, param)                                   \
1139         iscsi_conn_attr_show(param)                                     \
1140 static ISCSI_CLASS_ATTR(conn, field, S_IRUGO, show_conn_param_##param,  \
1141                         NULL);
1142
1143 iscsi_conn_attr(max_recv_dlength, ISCSI_PARAM_MAX_RECV_DLENGTH);
1144 iscsi_conn_attr(max_xmit_dlength, ISCSI_PARAM_MAX_XMIT_DLENGTH);
1145 iscsi_conn_attr(header_digest, ISCSI_PARAM_HDRDGST_EN);
1146 iscsi_conn_attr(data_digest, ISCSI_PARAM_DATADGST_EN);
1147 iscsi_conn_attr(ifmarker, ISCSI_PARAM_IFMARKER_EN);
1148 iscsi_conn_attr(ofmarker, ISCSI_PARAM_OFMARKER_EN);
1149 iscsi_conn_attr(persistent_port, ISCSI_PARAM_PERSISTENT_PORT);
1150 iscsi_conn_attr(port, ISCSI_PARAM_CONN_PORT);
1151 iscsi_conn_attr(exp_statsn, ISCSI_PARAM_EXP_STATSN);
1152 iscsi_conn_attr(persistent_address, ISCSI_PARAM_PERSISTENT_ADDRESS);
1153 iscsi_conn_attr(address, ISCSI_PARAM_CONN_ADDRESS);
1154
1155 #define iscsi_cdev_to_session(_cdev) \
1156         iscsi_dev_to_session(_cdev->dev)
1157
1158 /*
1159  * iSCSI session attrs
1160  */
1161 #define iscsi_session_attr_show(param)                                  \
1162 static ssize_t                                                          \
1163 show_session_param_##param(struct class_device *cdev, char *buf)        \
1164 {                                                                       \
1165         struct iscsi_cls_session *session = iscsi_cdev_to_session(cdev); \
1166         struct iscsi_transport *t = session->transport;                 \
1167         return t->get_session_param(session, param, buf);               \
1168 }
1169
1170 #define iscsi_session_attr(field, param)                                \
1171         iscsi_session_attr_show(param)                                  \
1172 static ISCSI_CLASS_ATTR(sess, field, S_IRUGO, show_session_param_##param, \
1173                         NULL);
1174
1175 iscsi_session_attr(targetname, ISCSI_PARAM_TARGET_NAME);
1176 iscsi_session_attr(initial_r2t, ISCSI_PARAM_INITIAL_R2T_EN);
1177 iscsi_session_attr(max_outstanding_r2t, ISCSI_PARAM_MAX_R2T);
1178 iscsi_session_attr(immediate_data, ISCSI_PARAM_IMM_DATA_EN);
1179 iscsi_session_attr(first_burst_len, ISCSI_PARAM_FIRST_BURST);
1180 iscsi_session_attr(max_burst_len, ISCSI_PARAM_MAX_BURST);
1181 iscsi_session_attr(data_pdu_in_order, ISCSI_PARAM_PDU_INORDER_EN);
1182 iscsi_session_attr(data_seq_in_order, ISCSI_PARAM_DATASEQ_INORDER_EN);
1183 iscsi_session_attr(erl, ISCSI_PARAM_ERL);
1184 iscsi_session_attr(tpgt, ISCSI_PARAM_TPGT);
1185
1186 #define iscsi_priv_session_attr_show(field, format)                     \
1187 static ssize_t                                                          \
1188 show_priv_session_##field(struct class_device *cdev, char *buf)         \
1189 {                                                                       \
1190         struct iscsi_cls_session *session = iscsi_cdev_to_session(cdev);\
1191         return sprintf(buf, format"\n", session->field);                \
1192 }
1193
1194 #define iscsi_priv_session_attr(field, format)                          \
1195         iscsi_priv_session_attr_show(field, format)                     \
1196 static ISCSI_CLASS_ATTR(priv_sess, field, S_IRUGO, show_priv_session_##field, \
1197                         NULL)
1198 iscsi_priv_session_attr(recovery_tmo, "%d");
1199
1200 #define SETUP_PRIV_SESSION_RD_ATTR(field)                               \
1201 do {                                                                    \
1202         priv->session_attrs[count] = &class_device_attr_priv_sess_##field; \
1203         count++;                                                        \
1204 } while (0)
1205
1206
1207 #define SETUP_SESSION_RD_ATTR(field, param_flag)                        \
1208 do {                                                                    \
1209         if (tt->param_mask & param_flag) {                              \
1210                 priv->session_attrs[count] = &class_device_attr_sess_##field; \
1211                 count++;                                                \
1212         }                                                               \
1213 } while (0)
1214
1215 #define SETUP_CONN_RD_ATTR(field, param_flag)                           \
1216 do {                                                                    \
1217         if (tt->param_mask & param_flag) {                              \
1218                 priv->conn_attrs[count] = &class_device_attr_conn_##field; \
1219                 count++;                                                \
1220         }                                                               \
1221 } while (0)
1222
1223 static int iscsi_session_match(struct attribute_container *cont,
1224                            struct device *dev)
1225 {
1226         struct iscsi_cls_session *session;
1227         struct Scsi_Host *shost;
1228         struct iscsi_internal *priv;
1229
1230         if (!iscsi_is_session_dev(dev))
1231                 return 0;
1232
1233         session = iscsi_dev_to_session(dev);
1234         shost = iscsi_session_to_shost(session);
1235         if (!shost->transportt)
1236                 return 0;
1237
1238         priv = to_iscsi_internal(shost->transportt);
1239         if (priv->session_cont.ac.class != &iscsi_session_class.class)
1240                 return 0;
1241
1242         return &priv->session_cont.ac == cont;
1243 }
1244
1245 static int iscsi_conn_match(struct attribute_container *cont,
1246                            struct device *dev)
1247 {
1248         struct iscsi_cls_session *session;
1249         struct iscsi_cls_conn *conn;
1250         struct Scsi_Host *shost;
1251         struct iscsi_internal *priv;
1252
1253         if (!iscsi_is_conn_dev(dev))
1254                 return 0;
1255
1256         conn = iscsi_dev_to_conn(dev);
1257         session = iscsi_dev_to_session(conn->dev.parent);
1258         shost = iscsi_session_to_shost(session);
1259
1260         if (!shost->transportt)
1261                 return 0;
1262
1263         priv = to_iscsi_internal(shost->transportt);
1264         if (priv->conn_cont.ac.class != &iscsi_connection_class.class)
1265                 return 0;
1266
1267         return &priv->conn_cont.ac == cont;
1268 }
1269
1270 static int iscsi_host_match(struct attribute_container *cont,
1271                             struct device *dev)
1272 {
1273         struct Scsi_Host *shost;
1274         struct iscsi_internal *priv;
1275
1276         if (!scsi_is_host_device(dev))
1277                 return 0;
1278
1279         shost = dev_to_shost(dev);
1280         if (!shost->transportt  ||
1281             shost->transportt->host_attrs.ac.class != &iscsi_host_class.class)
1282                 return 0;
1283
1284         priv = to_iscsi_internal(shost->transportt);
1285         return &priv->t.host_attrs.ac == cont;
1286 }
1287
1288 struct scsi_transport_template *
1289 iscsi_register_transport(struct iscsi_transport *tt)
1290 {
1291         struct iscsi_internal *priv;
1292         unsigned long flags;
1293         int count = 0, err;
1294
1295         BUG_ON(!tt);
1296
1297         priv = iscsi_if_transport_lookup(tt);
1298         if (priv)
1299                 return NULL;
1300
1301         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1302         if (!priv)
1303                 return NULL;
1304         INIT_LIST_HEAD(&priv->list);
1305         priv->daemon_pid = -1;
1306         priv->iscsi_transport = tt;
1307         priv->t.user_scan = iscsi_user_scan;
1308
1309         priv->cdev.class = &iscsi_transport_class;
1310         snprintf(priv->cdev.class_id, BUS_ID_SIZE, "%s", tt->name);
1311         err = class_device_register(&priv->cdev);
1312         if (err)
1313                 goto free_priv;
1314
1315         err = sysfs_create_group(&priv->cdev.kobj, &iscsi_transport_group);
1316         if (err)
1317                 goto unregister_cdev;
1318
1319         /* host parameters */
1320         priv->t.host_attrs.ac.attrs = &priv->host_attrs[0];
1321         priv->t.host_attrs.ac.class = &iscsi_host_class.class;
1322         priv->t.host_attrs.ac.match = iscsi_host_match;
1323         priv->t.host_size = sizeof(struct iscsi_host);
1324         priv->host_attrs[0] = NULL;
1325         transport_container_register(&priv->t.host_attrs);
1326
1327         /* connection parameters */
1328         priv->conn_cont.ac.attrs = &priv->conn_attrs[0];
1329         priv->conn_cont.ac.class = &iscsi_connection_class.class;
1330         priv->conn_cont.ac.match = iscsi_conn_match;
1331         transport_container_register(&priv->conn_cont);
1332
1333         SETUP_CONN_RD_ATTR(max_recv_dlength, ISCSI_MAX_RECV_DLENGTH);
1334         SETUP_CONN_RD_ATTR(max_xmit_dlength, ISCSI_MAX_XMIT_DLENGTH);
1335         SETUP_CONN_RD_ATTR(header_digest, ISCSI_HDRDGST_EN);
1336         SETUP_CONN_RD_ATTR(data_digest, ISCSI_DATADGST_EN);
1337         SETUP_CONN_RD_ATTR(ifmarker, ISCSI_IFMARKER_EN);
1338         SETUP_CONN_RD_ATTR(ofmarker, ISCSI_OFMARKER_EN);
1339         SETUP_CONN_RD_ATTR(address, ISCSI_CONN_ADDRESS);
1340         SETUP_CONN_RD_ATTR(port, ISCSI_CONN_PORT);
1341         SETUP_CONN_RD_ATTR(exp_statsn, ISCSI_EXP_STATSN);
1342         SETUP_CONN_RD_ATTR(persistent_address, ISCSI_PERSISTENT_ADDRESS);
1343         SETUP_CONN_RD_ATTR(persistent_port, ISCSI_PERSISTENT_PORT);
1344
1345         BUG_ON(count > ISCSI_CONN_ATTRS);
1346         priv->conn_attrs[count] = NULL;
1347         count = 0;
1348
1349         /* session parameters */
1350         priv->session_cont.ac.attrs = &priv->session_attrs[0];
1351         priv->session_cont.ac.class = &iscsi_session_class.class;
1352         priv->session_cont.ac.match = iscsi_session_match;
1353         transport_container_register(&priv->session_cont);
1354
1355         SETUP_SESSION_RD_ATTR(initial_r2t, ISCSI_INITIAL_R2T_EN);
1356         SETUP_SESSION_RD_ATTR(max_outstanding_r2t, ISCSI_MAX_R2T);
1357         SETUP_SESSION_RD_ATTR(immediate_data, ISCSI_IMM_DATA_EN);
1358         SETUP_SESSION_RD_ATTR(first_burst_len, ISCSI_FIRST_BURST);
1359         SETUP_SESSION_RD_ATTR(max_burst_len, ISCSI_MAX_BURST);
1360         SETUP_SESSION_RD_ATTR(data_pdu_in_order, ISCSI_PDU_INORDER_EN);
1361         SETUP_SESSION_RD_ATTR(data_seq_in_order, ISCSI_DATASEQ_INORDER_EN);
1362         SETUP_SESSION_RD_ATTR(erl, ISCSI_ERL);
1363         SETUP_SESSION_RD_ATTR(targetname, ISCSI_TARGET_NAME);
1364         SETUP_SESSION_RD_ATTR(tpgt, ISCSI_TPGT);
1365         SETUP_PRIV_SESSION_RD_ATTR(recovery_tmo);
1366
1367         BUG_ON(count > ISCSI_SESSION_ATTRS);
1368         priv->session_attrs[count] = NULL;
1369
1370         spin_lock_irqsave(&iscsi_transport_lock, flags);
1371         list_add(&priv->list, &iscsi_transports);
1372         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1373
1374         printk(KERN_NOTICE "iscsi: registered transport (%s)\n", tt->name);
1375         return &priv->t;
1376
1377 unregister_cdev:
1378         class_device_unregister(&priv->cdev);
1379 free_priv:
1380         kfree(priv);
1381         return NULL;
1382 }
1383 EXPORT_SYMBOL_GPL(iscsi_register_transport);
1384
1385 int iscsi_unregister_transport(struct iscsi_transport *tt)
1386 {
1387         struct iscsi_internal *priv;
1388         unsigned long flags;
1389
1390         BUG_ON(!tt);
1391
1392         mutex_lock(&rx_queue_mutex);
1393
1394         priv = iscsi_if_transport_lookup(tt);
1395         BUG_ON (!priv);
1396
1397         spin_lock_irqsave(&iscsi_transport_lock, flags);
1398         list_del(&priv->list);
1399         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1400
1401         transport_container_unregister(&priv->conn_cont);
1402         transport_container_unregister(&priv->session_cont);
1403         transport_container_unregister(&priv->t.host_attrs);
1404
1405         sysfs_remove_group(&priv->cdev.kobj, &iscsi_transport_group);
1406         class_device_unregister(&priv->cdev);
1407         mutex_unlock(&rx_queue_mutex);
1408
1409         return 0;
1410 }
1411 EXPORT_SYMBOL_GPL(iscsi_unregister_transport);
1412
1413 static __init int iscsi_transport_init(void)
1414 {
1415         int err;
1416
1417         printk(KERN_INFO "Loading iSCSI transport class v%s.",
1418                 ISCSI_TRANSPORT_VERSION);
1419
1420         err = class_register(&iscsi_transport_class);
1421         if (err)
1422                 return err;
1423
1424         err = transport_class_register(&iscsi_host_class);
1425         if (err)
1426                 goto unregister_transport_class;
1427
1428         err = transport_class_register(&iscsi_connection_class);
1429         if (err)
1430                 goto unregister_host_class;
1431
1432         err = transport_class_register(&iscsi_session_class);
1433         if (err)
1434                 goto unregister_conn_class;
1435
1436         nls = netlink_kernel_create(NETLINK_ISCSI, 1, iscsi_if_rx,
1437                         THIS_MODULE);
1438         if (!nls) {
1439                 err = -ENOBUFS;
1440                 goto unregister_session_class;
1441         }
1442
1443         return 0;
1444
1445 unregister_session_class:
1446         transport_class_unregister(&iscsi_session_class);
1447 unregister_conn_class:
1448         transport_class_unregister(&iscsi_connection_class);
1449 unregister_host_class:
1450         transport_class_unregister(&iscsi_host_class);
1451 unregister_transport_class:
1452         class_unregister(&iscsi_transport_class);
1453         return err;
1454 }
1455
1456 static void __exit iscsi_transport_exit(void)
1457 {
1458         sock_release(nls->sk_socket);
1459         transport_class_unregister(&iscsi_connection_class);
1460         transport_class_unregister(&iscsi_session_class);
1461         transport_class_unregister(&iscsi_host_class);
1462         class_unregister(&iscsi_transport_class);
1463 }
1464
1465 module_init(iscsi_transport_init);
1466 module_exit(iscsi_transport_exit);
1467
1468 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
1469               "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
1470               "Alex Aizman <itn780@yahoo.com>");
1471 MODULE_DESCRIPTION("iSCSI Transport Interface");
1472 MODULE_LICENSE("GPL");
1473 MODULE_VERSION(ISCSI_TRANSPORT_VERSION);