Merge branch 'for-linus' of git://linux-nfs.org/~bfields/linux
[linux-2.6] / 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 19
34 #define ISCSI_CONN_ATTRS 13
35 #define ISCSI_HOST_ATTRS 4
36 #define ISCSI_TRANSPORT_VERSION "2.0-868"
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 atomic_t iscsi_session_nr; /* sysfs session id for next new session */
53 static struct workqueue_struct *iscsi_eh_timer_workq;
54
55 /*
56  * list of registered transports and lock that must
57  * be held while accessing list. The iscsi_transport_lock must
58  * be acquired after the rx_queue_mutex.
59  */
60 static LIST_HEAD(iscsi_transports);
61 static DEFINE_SPINLOCK(iscsi_transport_lock);
62
63 #define to_iscsi_internal(tmpl) \
64         container_of(tmpl, struct iscsi_internal, t)
65
66 #define cdev_to_iscsi_internal(_cdev) \
67         container_of(_cdev, struct iscsi_internal, cdev)
68
69 static void iscsi_transport_release(struct class_device *cdev)
70 {
71         struct iscsi_internal *priv = cdev_to_iscsi_internal(cdev);
72         kfree(priv);
73 }
74
75 /*
76  * iscsi_transport_class represents the iscsi_transports that are
77  * registered.
78  */
79 static struct class iscsi_transport_class = {
80         .name = "iscsi_transport",
81         .release = iscsi_transport_release,
82 };
83
84 static ssize_t
85 show_transport_handle(struct class_device *cdev, char *buf)
86 {
87         struct iscsi_internal *priv = cdev_to_iscsi_internal(cdev);
88         return sprintf(buf, "%llu\n", (unsigned long long)iscsi_handle(priv->iscsi_transport));
89 }
90 static CLASS_DEVICE_ATTR(handle, S_IRUGO, show_transport_handle, NULL);
91
92 #define show_transport_attr(name, format)                               \
93 static ssize_t                                                          \
94 show_transport_##name(struct class_device *cdev, char *buf)             \
95 {                                                                       \
96         struct iscsi_internal *priv = cdev_to_iscsi_internal(cdev);     \
97         return sprintf(buf, format"\n", priv->iscsi_transport->name);   \
98 }                                                                       \
99 static CLASS_DEVICE_ATTR(name, S_IRUGO, show_transport_##name, NULL);
100
101 show_transport_attr(caps, "0x%x");
102 show_transport_attr(max_lun, "%d");
103 show_transport_attr(max_conn, "%d");
104 show_transport_attr(max_cmd_len, "%d");
105
106 static struct attribute *iscsi_transport_attrs[] = {
107         &class_device_attr_handle.attr,
108         &class_device_attr_caps.attr,
109         &class_device_attr_max_lun.attr,
110         &class_device_attr_max_conn.attr,
111         &class_device_attr_max_cmd_len.attr,
112         NULL,
113 };
114
115 static struct attribute_group iscsi_transport_group = {
116         .attrs = iscsi_transport_attrs,
117 };
118
119
120
121 static int iscsi_setup_host(struct transport_container *tc, struct device *dev,
122                             struct class_device *cdev)
123 {
124         struct Scsi_Host *shost = dev_to_shost(dev);
125         struct iscsi_host *ihost = shost->shost_data;
126
127         memset(ihost, 0, sizeof(*ihost));
128         INIT_LIST_HEAD(&ihost->sessions);
129         mutex_init(&ihost->mutex);
130         atomic_set(&ihost->nr_scans, 0);
131
132         snprintf(ihost->scan_workq_name, KOBJ_NAME_LEN, "iscsi_scan_%d",
133                 shost->host_no);
134         ihost->scan_workq = create_singlethread_workqueue(
135                                                 ihost->scan_workq_name);
136         if (!ihost->scan_workq)
137                 return -ENOMEM;
138         return 0;
139 }
140
141 static int iscsi_remove_host(struct transport_container *tc, struct device *dev,
142                              struct class_device *cdev)
143 {
144         struct Scsi_Host *shost = dev_to_shost(dev);
145         struct iscsi_host *ihost = shost->shost_data;
146
147         destroy_workqueue(ihost->scan_workq);
148         return 0;
149 }
150
151 static DECLARE_TRANSPORT_CLASS(iscsi_host_class,
152                                "iscsi_host",
153                                iscsi_setup_host,
154                                iscsi_remove_host,
155                                NULL);
156
157 static DECLARE_TRANSPORT_CLASS(iscsi_session_class,
158                                "iscsi_session",
159                                NULL,
160                                NULL,
161                                NULL);
162
163 static DECLARE_TRANSPORT_CLASS(iscsi_connection_class,
164                                "iscsi_connection",
165                                NULL,
166                                NULL,
167                                NULL);
168
169 static struct sock *nls;
170 static DEFINE_MUTEX(rx_queue_mutex);
171
172 static LIST_HEAD(sesslist);
173 static DEFINE_SPINLOCK(sesslock);
174 static LIST_HEAD(connlist);
175 static DEFINE_SPINLOCK(connlock);
176
177 static uint32_t iscsi_conn_get_sid(struct iscsi_cls_conn *conn)
178 {
179         struct iscsi_cls_session *sess = iscsi_dev_to_session(conn->dev.parent);
180         return sess->sid;
181 }
182
183 /*
184  * Returns the matching session to a given sid
185  */
186 static struct iscsi_cls_session *iscsi_session_lookup(uint32_t sid)
187 {
188         unsigned long flags;
189         struct iscsi_cls_session *sess;
190
191         spin_lock_irqsave(&sesslock, flags);
192         list_for_each_entry(sess, &sesslist, sess_list) {
193                 if (sess->sid == sid) {
194                         spin_unlock_irqrestore(&sesslock, flags);
195                         return sess;
196                 }
197         }
198         spin_unlock_irqrestore(&sesslock, flags);
199         return NULL;
200 }
201
202 /*
203  * Returns the matching connection to a given sid / cid tuple
204  */
205 static struct iscsi_cls_conn *iscsi_conn_lookup(uint32_t sid, uint32_t cid)
206 {
207         unsigned long flags;
208         struct iscsi_cls_conn *conn;
209
210         spin_lock_irqsave(&connlock, flags);
211         list_for_each_entry(conn, &connlist, conn_list) {
212                 if ((conn->cid == cid) && (iscsi_conn_get_sid(conn) == sid)) {
213                         spin_unlock_irqrestore(&connlock, flags);
214                         return conn;
215                 }
216         }
217         spin_unlock_irqrestore(&connlock, flags);
218         return NULL;
219 }
220
221 /*
222  * The following functions can be used by LLDs that allocate
223  * their own scsi_hosts or by software iscsi LLDs
224  */
225 static struct {
226         int value;
227         char *name;
228 } iscsi_session_state_names[] = {
229         { ISCSI_SESSION_LOGGED_IN,      "LOGGED_IN" },
230         { ISCSI_SESSION_FAILED,         "FAILED" },
231         { ISCSI_SESSION_FREE,           "FREE" },
232 };
233
234 const char *iscsi_session_state_name(int state)
235 {
236         int i;
237         char *name = NULL;
238
239         for (i = 0; i < ARRAY_SIZE(iscsi_session_state_names); i++) {
240                 if (iscsi_session_state_names[i].value == state) {
241                         name = iscsi_session_state_names[i].name;
242                         break;
243                 }
244         }
245         return name;
246 }
247
248 int iscsi_session_chkready(struct iscsi_cls_session *session)
249 {
250         unsigned long flags;
251         int err;
252
253         spin_lock_irqsave(&session->lock, flags);
254         switch (session->state) {
255         case ISCSI_SESSION_LOGGED_IN:
256                 err = 0;
257                 break;
258         case ISCSI_SESSION_FAILED:
259                 err = DID_IMM_RETRY << 16;
260                 break;
261         case ISCSI_SESSION_FREE:
262                 err = DID_NO_CONNECT << 16;
263                 break;
264         default:
265                 err = DID_NO_CONNECT << 16;
266                 break;
267         }
268         spin_unlock_irqrestore(&session->lock, flags);
269         return err;
270 }
271 EXPORT_SYMBOL_GPL(iscsi_session_chkready);
272
273 static void iscsi_session_release(struct device *dev)
274 {
275         struct iscsi_cls_session *session = iscsi_dev_to_session(dev);
276         struct Scsi_Host *shost;
277
278         shost = iscsi_session_to_shost(session);
279         scsi_host_put(shost);
280         kfree(session);
281 }
282
283 static int iscsi_is_session_dev(const struct device *dev)
284 {
285         return dev->release == iscsi_session_release;
286 }
287
288 /**
289  * iscsi_scan_finished - helper to report when running scans are done
290  * @shost: scsi host
291  * @time: scan run time
292  *
293  * This function can be used by drives like qla4xxx to report to the scsi
294  * layer when the scans it kicked off at module load time are done.
295  */
296 int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time)
297 {
298         struct iscsi_host *ihost = shost->shost_data;
299         /*
300          * qla4xxx will have kicked off some session unblocks before calling
301          * scsi_scan_host, so just wait for them to complete.
302          */
303         return !atomic_read(&ihost->nr_scans);
304 }
305 EXPORT_SYMBOL_GPL(iscsi_scan_finished);
306
307 static int iscsi_user_scan(struct Scsi_Host *shost, uint channel,
308                            uint id, uint lun)
309 {
310         struct iscsi_host *ihost = shost->shost_data;
311         struct iscsi_cls_session *session;
312
313         mutex_lock(&ihost->mutex);
314         list_for_each_entry(session, &ihost->sessions, host_list) {
315                 if ((channel == SCAN_WILD_CARD || channel == 0) &&
316                     (id == SCAN_WILD_CARD || id == session->target_id))
317                         scsi_scan_target(&session->dev, 0,
318                                          session->target_id, lun, 1);
319         }
320         mutex_unlock(&ihost->mutex);
321
322         return 0;
323 }
324
325 static void iscsi_scan_session(struct work_struct *work)
326 {
327         struct iscsi_cls_session *session =
328                         container_of(work, struct iscsi_cls_session, scan_work);
329         struct Scsi_Host *shost = iscsi_session_to_shost(session);
330         struct iscsi_host *ihost = shost->shost_data;
331         unsigned long flags;
332
333         spin_lock_irqsave(&session->lock, flags);
334         if (session->state != ISCSI_SESSION_LOGGED_IN) {
335                 spin_unlock_irqrestore(&session->lock, flags);
336                 goto done;
337         }
338         spin_unlock_irqrestore(&session->lock, flags);
339
340         scsi_scan_target(&session->dev, 0, session->target_id,
341                          SCAN_WILD_CARD, 1);
342 done:
343         atomic_dec(&ihost->nr_scans);
344 }
345
346 static void session_recovery_timedout(struct work_struct *work)
347 {
348         struct iscsi_cls_session *session =
349                 container_of(work, struct iscsi_cls_session,
350                              recovery_work.work);
351         unsigned long flags;
352
353         iscsi_cls_session_printk(KERN_INFO, session,
354                                  "session recovery timed out after %d secs\n",
355                                  session->recovery_tmo);
356
357         spin_lock_irqsave(&session->lock, flags);
358         switch (session->state) {
359         case ISCSI_SESSION_FAILED:
360                 session->state = ISCSI_SESSION_FREE;
361                 break;
362         case ISCSI_SESSION_LOGGED_IN:
363         case ISCSI_SESSION_FREE:
364                 /* we raced with the unblock's flush */
365                 spin_unlock_irqrestore(&session->lock, flags);
366                 return;
367         }
368         spin_unlock_irqrestore(&session->lock, flags);
369
370         if (session->transport->session_recovery_timedout)
371                 session->transport->session_recovery_timedout(session);
372
373         scsi_target_unblock(&session->dev);
374 }
375
376 void __iscsi_unblock_session(struct iscsi_cls_session *session)
377 {
378         if (!cancel_delayed_work(&session->recovery_work))
379                 flush_workqueue(iscsi_eh_timer_workq);
380         scsi_target_unblock(&session->dev);
381 }
382
383 void iscsi_unblock_session(struct iscsi_cls_session *session)
384 {
385         struct Scsi_Host *shost = iscsi_session_to_shost(session);
386         struct iscsi_host *ihost = shost->shost_data;
387         unsigned long flags;
388
389         spin_lock_irqsave(&session->lock, flags);
390         session->state = ISCSI_SESSION_LOGGED_IN;
391         spin_unlock_irqrestore(&session->lock, flags);
392
393         __iscsi_unblock_session(session);
394         /*
395          * Only do kernel scanning if the driver is properly hooked into
396          * the async scanning code (drivers like iscsi_tcp do login and
397          * scanning from userspace).
398          */
399         if (shost->hostt->scan_finished) {
400                 if (queue_work(ihost->scan_workq, &session->scan_work))
401                         atomic_inc(&ihost->nr_scans);
402         }
403 }
404 EXPORT_SYMBOL_GPL(iscsi_unblock_session);
405
406 void iscsi_block_session(struct iscsi_cls_session *session)
407 {
408         unsigned long flags;
409
410         spin_lock_irqsave(&session->lock, flags);
411         session->state = ISCSI_SESSION_FAILED;
412         spin_unlock_irqrestore(&session->lock, flags);
413
414         scsi_target_block(&session->dev);
415         queue_delayed_work(iscsi_eh_timer_workq, &session->recovery_work,
416                            session->recovery_tmo * HZ);
417 }
418 EXPORT_SYMBOL_GPL(iscsi_block_session);
419
420 static void __iscsi_unbind_session(struct work_struct *work)
421 {
422         struct iscsi_cls_session *session =
423                         container_of(work, struct iscsi_cls_session,
424                                      unbind_work);
425         struct Scsi_Host *shost = iscsi_session_to_shost(session);
426         struct iscsi_host *ihost = shost->shost_data;
427
428         /* Prevent new scans and make sure scanning is not in progress */
429         mutex_lock(&ihost->mutex);
430         if (list_empty(&session->host_list)) {
431                 mutex_unlock(&ihost->mutex);
432                 return;
433         }
434         list_del_init(&session->host_list);
435         mutex_unlock(&ihost->mutex);
436
437         scsi_remove_target(&session->dev);
438         iscsi_session_event(session, ISCSI_KEVENT_UNBIND_SESSION);
439 }
440
441 static int iscsi_unbind_session(struct iscsi_cls_session *session)
442 {
443         struct Scsi_Host *shost = iscsi_session_to_shost(session);
444         struct iscsi_host *ihost = shost->shost_data;
445
446         return queue_work(ihost->scan_workq, &session->unbind_work);
447 }
448
449 struct iscsi_cls_session *
450 iscsi_alloc_session(struct Scsi_Host *shost,
451                     struct iscsi_transport *transport)
452 {
453         struct iscsi_cls_session *session;
454
455         session = kzalloc(sizeof(*session) + transport->sessiondata_size,
456                           GFP_KERNEL);
457         if (!session)
458                 return NULL;
459
460         session->transport = transport;
461         session->recovery_tmo = 120;
462         session->state = ISCSI_SESSION_FREE;
463         INIT_DELAYED_WORK(&session->recovery_work, session_recovery_timedout);
464         INIT_LIST_HEAD(&session->host_list);
465         INIT_LIST_HEAD(&session->sess_list);
466         INIT_WORK(&session->unbind_work, __iscsi_unbind_session);
467         INIT_WORK(&session->scan_work, iscsi_scan_session);
468         spin_lock_init(&session->lock);
469
470         /* this is released in the dev's release function */
471         scsi_host_get(shost);
472         session->dev.parent = &shost->shost_gendev;
473         session->dev.release = iscsi_session_release;
474         device_initialize(&session->dev);
475         if (transport->sessiondata_size)
476                 session->dd_data = &session[1];
477         return session;
478 }
479 EXPORT_SYMBOL_GPL(iscsi_alloc_session);
480
481 int iscsi_add_session(struct iscsi_cls_session *session, unsigned int target_id)
482 {
483         struct Scsi_Host *shost = iscsi_session_to_shost(session);
484         struct iscsi_host *ihost;
485         unsigned long flags;
486         int err;
487
488         ihost = shost->shost_data;
489         session->sid = atomic_add_return(1, &iscsi_session_nr);
490         session->target_id = target_id;
491
492         snprintf(session->dev.bus_id, BUS_ID_SIZE, "session%u",
493                  session->sid);
494         err = device_add(&session->dev);
495         if (err) {
496                 iscsi_cls_session_printk(KERN_ERR, session,
497                                          "could not register session's dev\n");
498                 goto release_host;
499         }
500         transport_register_device(&session->dev);
501
502         spin_lock_irqsave(&sesslock, flags);
503         list_add(&session->sess_list, &sesslist);
504         spin_unlock_irqrestore(&sesslock, flags);
505
506         mutex_lock(&ihost->mutex);
507         list_add(&session->host_list, &ihost->sessions);
508         mutex_unlock(&ihost->mutex);
509
510         iscsi_session_event(session, ISCSI_KEVENT_CREATE_SESSION);
511         return 0;
512
513 release_host:
514         scsi_host_put(shost);
515         return err;
516 }
517 EXPORT_SYMBOL_GPL(iscsi_add_session);
518
519 /**
520  * iscsi_create_session - create iscsi class session
521  * @shost: scsi host
522  * @transport: iscsi transport
523  * @target_id: which target
524  *
525  * This can be called from a LLD or iscsi_transport.
526  */
527 struct iscsi_cls_session *
528 iscsi_create_session(struct Scsi_Host *shost,
529                      struct iscsi_transport *transport,
530                      unsigned int target_id)
531 {
532         struct iscsi_cls_session *session;
533
534         session = iscsi_alloc_session(shost, transport);
535         if (!session)
536                 return NULL;
537
538         if (iscsi_add_session(session, target_id)) {
539                 iscsi_free_session(session);
540                 return NULL;
541         }
542         return session;
543 }
544 EXPORT_SYMBOL_GPL(iscsi_create_session);
545
546 static void iscsi_conn_release(struct device *dev)
547 {
548         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev);
549         struct device *parent = conn->dev.parent;
550
551         kfree(conn);
552         put_device(parent);
553 }
554
555 static int iscsi_is_conn_dev(const struct device *dev)
556 {
557         return dev->release == iscsi_conn_release;
558 }
559
560 static int iscsi_iter_destroy_conn_fn(struct device *dev, void *data)
561 {
562         if (!iscsi_is_conn_dev(dev))
563                 return 0;
564         return iscsi_destroy_conn(iscsi_dev_to_conn(dev));
565 }
566
567 void iscsi_remove_session(struct iscsi_cls_session *session)
568 {
569         struct Scsi_Host *shost = iscsi_session_to_shost(session);
570         struct iscsi_host *ihost = shost->shost_data;
571         unsigned long flags;
572         int err;
573
574         spin_lock_irqsave(&sesslock, flags);
575         list_del(&session->sess_list);
576         spin_unlock_irqrestore(&sesslock, flags);
577
578         /*
579          * If we are blocked let commands flow again. The lld or iscsi
580          * layer should set up the queuecommand to fail commands.
581          */
582         spin_lock_irqsave(&session->lock, flags);
583         session->state = ISCSI_SESSION_FREE;
584         spin_unlock_irqrestore(&session->lock, flags);
585         __iscsi_unblock_session(session);
586         __iscsi_unbind_session(&session->unbind_work);
587
588         /* flush running scans */
589         flush_workqueue(ihost->scan_workq);
590         /*
591          * If the session dropped while removing devices then we need to make
592          * sure it is not blocked
593          */
594         if (!cancel_delayed_work(&session->recovery_work))
595                 flush_workqueue(iscsi_eh_timer_workq);
596
597         /* hw iscsi may not have removed all connections from session */
598         err = device_for_each_child(&session->dev, NULL,
599                                     iscsi_iter_destroy_conn_fn);
600         if (err)
601                 iscsi_cls_session_printk(KERN_ERR, session,
602                                          "Could not delete all connections "
603                                          "for session. Error %d.\n", err);
604
605         transport_unregister_device(&session->dev);
606         device_del(&session->dev);
607 }
608 EXPORT_SYMBOL_GPL(iscsi_remove_session);
609
610 void iscsi_free_session(struct iscsi_cls_session *session)
611 {
612         iscsi_session_event(session, ISCSI_KEVENT_DESTROY_SESSION);
613         put_device(&session->dev);
614 }
615 EXPORT_SYMBOL_GPL(iscsi_free_session);
616
617 /**
618  * iscsi_destroy_session - destroy iscsi session
619  * @session: iscsi_session
620  *
621  * Can be called by a LLD or iscsi_transport. There must not be
622  * any running connections.
623  */
624 int iscsi_destroy_session(struct iscsi_cls_session *session)
625 {
626         iscsi_remove_session(session);
627         iscsi_free_session(session);
628         return 0;
629 }
630 EXPORT_SYMBOL_GPL(iscsi_destroy_session);
631
632 /**
633  * iscsi_create_conn - create iscsi class connection
634  * @session: iscsi cls session
635  * @cid: connection id
636  *
637  * This can be called from a LLD or iscsi_transport. The connection
638  * is child of the session so cid must be unique for all connections
639  * on the session.
640  *
641  * Since we do not support MCS, cid will normally be zero. In some cases
642  * for software iscsi we could be trying to preallocate a connection struct
643  * in which case there could be two connection structs and cid would be
644  * non-zero.
645  */
646 struct iscsi_cls_conn *
647 iscsi_create_conn(struct iscsi_cls_session *session, uint32_t cid)
648 {
649         struct iscsi_transport *transport = session->transport;
650         struct iscsi_cls_conn *conn;
651         unsigned long flags;
652         int err;
653
654         conn = kzalloc(sizeof(*conn) + transport->conndata_size, GFP_KERNEL);
655         if (!conn)
656                 return NULL;
657
658         if (transport->conndata_size)
659                 conn->dd_data = &conn[1];
660
661         INIT_LIST_HEAD(&conn->conn_list);
662         conn->transport = transport;
663         conn->cid = cid;
664
665         /* this is released in the dev's release function */
666         if (!get_device(&session->dev))
667                 goto free_conn;
668
669         snprintf(conn->dev.bus_id, BUS_ID_SIZE, "connection%d:%u",
670                  session->sid, cid);
671         conn->dev.parent = &session->dev;
672         conn->dev.release = iscsi_conn_release;
673         err = device_register(&conn->dev);
674         if (err) {
675                 iscsi_cls_session_printk(KERN_ERR, session, "could not "
676                                          "register connection's dev\n");
677                 goto release_parent_ref;
678         }
679         transport_register_device(&conn->dev);
680
681         spin_lock_irqsave(&connlock, flags);
682         list_add(&conn->conn_list, &connlist);
683         conn->active = 1;
684         spin_unlock_irqrestore(&connlock, flags);
685         return conn;
686
687 release_parent_ref:
688         put_device(&session->dev);
689 free_conn:
690         kfree(conn);
691         return NULL;
692 }
693
694 EXPORT_SYMBOL_GPL(iscsi_create_conn);
695
696 /**
697  * iscsi_destroy_conn - destroy iscsi class connection
698  * @conn: iscsi cls session
699  *
700  * This can be called from a LLD or iscsi_transport.
701  */
702 int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
703 {
704         unsigned long flags;
705
706         spin_lock_irqsave(&connlock, flags);
707         conn->active = 0;
708         list_del(&conn->conn_list);
709         spin_unlock_irqrestore(&connlock, flags);
710
711         transport_unregister_device(&conn->dev);
712         device_unregister(&conn->dev);
713         return 0;
714 }
715 EXPORT_SYMBOL_GPL(iscsi_destroy_conn);
716
717 /*
718  * iscsi interface functions
719  */
720 static struct iscsi_internal *
721 iscsi_if_transport_lookup(struct iscsi_transport *tt)
722 {
723         struct iscsi_internal *priv;
724         unsigned long flags;
725
726         spin_lock_irqsave(&iscsi_transport_lock, flags);
727         list_for_each_entry(priv, &iscsi_transports, list) {
728                 if (tt == priv->iscsi_transport) {
729                         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
730                         return priv;
731                 }
732         }
733         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
734         return NULL;
735 }
736
737 static int
738 iscsi_broadcast_skb(struct sk_buff *skb, gfp_t gfp)
739 {
740         int rc;
741
742         rc = netlink_broadcast(nls, skb, 0, 1, gfp);
743         if (rc < 0) {
744                 printk(KERN_ERR "iscsi: can not broadcast skb (%d)\n", rc);
745                 return rc;
746         }
747
748         return 0;
749 }
750
751 static int
752 iscsi_unicast_skb(struct sk_buff *skb, int pid)
753 {
754         int rc;
755
756         rc = netlink_unicast(nls, skb, pid, MSG_DONTWAIT);
757         if (rc < 0) {
758                 printk(KERN_ERR "iscsi: can not unicast skb (%d)\n", rc);
759                 return rc;
760         }
761
762         return 0;
763 }
764
765 int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
766                    char *data, uint32_t data_size)
767 {
768         struct nlmsghdr *nlh;
769         struct sk_buff *skb;
770         struct iscsi_uevent *ev;
771         char *pdu;
772         struct iscsi_internal *priv;
773         int len = NLMSG_SPACE(sizeof(*ev) + sizeof(struct iscsi_hdr) +
774                               data_size);
775
776         priv = iscsi_if_transport_lookup(conn->transport);
777         if (!priv)
778                 return -EINVAL;
779
780         skb = alloc_skb(len, GFP_ATOMIC);
781         if (!skb) {
782                 iscsi_conn_error(conn, ISCSI_ERR_CONN_FAILED);
783                 iscsi_cls_conn_printk(KERN_ERR, conn, "can not deliver "
784                                       "control PDU: OOM\n");
785                 return -ENOMEM;
786         }
787
788         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
789         ev = NLMSG_DATA(nlh);
790         memset(ev, 0, sizeof(*ev));
791         ev->transport_handle = iscsi_handle(conn->transport);
792         ev->type = ISCSI_KEVENT_RECV_PDU;
793         ev->r.recv_req.cid = conn->cid;
794         ev->r.recv_req.sid = iscsi_conn_get_sid(conn);
795         pdu = (char*)ev + sizeof(*ev);
796         memcpy(pdu, hdr, sizeof(struct iscsi_hdr));
797         memcpy(pdu + sizeof(struct iscsi_hdr), data, data_size);
798
799         return iscsi_unicast_skb(skb, priv->daemon_pid);
800 }
801 EXPORT_SYMBOL_GPL(iscsi_recv_pdu);
802
803 void iscsi_conn_error(struct iscsi_cls_conn *conn, enum iscsi_err error)
804 {
805         struct iscsi_cls_session *session = iscsi_conn_to_session(conn);
806         struct nlmsghdr *nlh;
807         struct sk_buff  *skb;
808         struct iscsi_uevent *ev;
809         struct iscsi_internal *priv;
810         int len = NLMSG_SPACE(sizeof(*ev));
811         unsigned long flags;
812
813         priv = iscsi_if_transport_lookup(conn->transport);
814         if (!priv)
815                 return;
816
817         spin_lock_irqsave(&session->lock, flags);
818         if (session->state == ISCSI_SESSION_LOGGED_IN)
819                 session->state = ISCSI_SESSION_FAILED;
820         spin_unlock_irqrestore(&session->lock, flags);
821
822         skb = alloc_skb(len, GFP_ATOMIC);
823         if (!skb) {
824                 iscsi_cls_conn_printk(KERN_ERR, conn, "gracefully ignored "
825                                       "conn error (%d)\n", error);
826                 return;
827         }
828
829         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
830         ev = NLMSG_DATA(nlh);
831         ev->transport_handle = iscsi_handle(conn->transport);
832         ev->type = ISCSI_KEVENT_CONN_ERROR;
833         ev->r.connerror.error = error;
834         ev->r.connerror.cid = conn->cid;
835         ev->r.connerror.sid = iscsi_conn_get_sid(conn);
836
837         iscsi_broadcast_skb(skb, GFP_ATOMIC);
838
839         iscsi_cls_conn_printk(KERN_INFO, conn, "detected conn error (%d)\n",
840                               error);
841 }
842 EXPORT_SYMBOL_GPL(iscsi_conn_error);
843
844 static int
845 iscsi_if_send_reply(int pid, int seq, int type, int done, int multi,
846                       void *payload, int size)
847 {
848         struct sk_buff  *skb;
849         struct nlmsghdr *nlh;
850         int len = NLMSG_SPACE(size);
851         int flags = multi ? NLM_F_MULTI : 0;
852         int t = done ? NLMSG_DONE : type;
853
854         skb = alloc_skb(len, GFP_ATOMIC);
855         if (!skb) {
856                 printk(KERN_ERR "Could not allocate skb to send reply.\n");
857                 return -ENOMEM;
858         }
859
860         nlh = __nlmsg_put(skb, pid, seq, t, (len - sizeof(*nlh)), 0);
861         nlh->nlmsg_flags = flags;
862         memcpy(NLMSG_DATA(nlh), payload, size);
863         return iscsi_unicast_skb(skb, pid);
864 }
865
866 static int
867 iscsi_if_get_stats(struct iscsi_transport *transport, struct nlmsghdr *nlh)
868 {
869         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
870         struct iscsi_stats *stats;
871         struct sk_buff *skbstat;
872         struct iscsi_cls_conn *conn;
873         struct nlmsghdr *nlhstat;
874         struct iscsi_uevent *evstat;
875         struct iscsi_internal *priv;
876         int len = NLMSG_SPACE(sizeof(*ev) +
877                               sizeof(struct iscsi_stats) +
878                               sizeof(struct iscsi_stats_custom) *
879                               ISCSI_STATS_CUSTOM_MAX);
880         int err = 0;
881
882         priv = iscsi_if_transport_lookup(transport);
883         if (!priv)
884                 return -EINVAL;
885
886         conn = iscsi_conn_lookup(ev->u.get_stats.sid, ev->u.get_stats.cid);
887         if (!conn)
888                 return -EEXIST;
889
890         do {
891                 int actual_size;
892
893                 skbstat = alloc_skb(len, GFP_ATOMIC);
894                 if (!skbstat) {
895                         iscsi_cls_conn_printk(KERN_ERR, conn, "can not "
896                                               "deliver stats: OOM\n");
897                         return -ENOMEM;
898                 }
899
900                 nlhstat = __nlmsg_put(skbstat, priv->daemon_pid, 0, 0,
901                                       (len - sizeof(*nlhstat)), 0);
902                 evstat = NLMSG_DATA(nlhstat);
903                 memset(evstat, 0, sizeof(*evstat));
904                 evstat->transport_handle = iscsi_handle(conn->transport);
905                 evstat->type = nlh->nlmsg_type;
906                 evstat->u.get_stats.cid =
907                         ev->u.get_stats.cid;
908                 evstat->u.get_stats.sid =
909                         ev->u.get_stats.sid;
910                 stats = (struct iscsi_stats *)
911                         ((char*)evstat + sizeof(*evstat));
912                 memset(stats, 0, sizeof(*stats));
913
914                 transport->get_stats(conn, stats);
915                 actual_size = NLMSG_SPACE(sizeof(struct iscsi_uevent) +
916                                           sizeof(struct iscsi_stats) +
917                                           sizeof(struct iscsi_stats_custom) *
918                                           stats->custom_length);
919                 actual_size -= sizeof(*nlhstat);
920                 actual_size = NLMSG_LENGTH(actual_size);
921                 skb_trim(skbstat, NLMSG_ALIGN(actual_size));
922                 nlhstat->nlmsg_len = actual_size;
923
924                 err = iscsi_unicast_skb(skbstat, priv->daemon_pid);
925         } while (err < 0 && err != -ECONNREFUSED);
926
927         return err;
928 }
929
930 /**
931  * iscsi_session_event - send session destr. completion event
932  * @session: iscsi class session
933  * @event: type of event
934  */
935 int iscsi_session_event(struct iscsi_cls_session *session,
936                         enum iscsi_uevent_e event)
937 {
938         struct iscsi_internal *priv;
939         struct Scsi_Host *shost;
940         struct iscsi_uevent *ev;
941         struct sk_buff  *skb;
942         struct nlmsghdr *nlh;
943         int rc, len = NLMSG_SPACE(sizeof(*ev));
944
945         priv = iscsi_if_transport_lookup(session->transport);
946         if (!priv)
947                 return -EINVAL;
948         shost = iscsi_session_to_shost(session);
949
950         skb = alloc_skb(len, GFP_KERNEL);
951         if (!skb) {
952                 iscsi_cls_session_printk(KERN_ERR, session,
953                                          "Cannot notify userspace of session "
954                                          "event %u\n", event);
955                 return -ENOMEM;
956         }
957
958         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
959         ev = NLMSG_DATA(nlh);
960         ev->transport_handle = iscsi_handle(session->transport);
961
962         ev->type = event;
963         switch (event) {
964         case ISCSI_KEVENT_DESTROY_SESSION:
965                 ev->r.d_session.host_no = shost->host_no;
966                 ev->r.d_session.sid = session->sid;
967                 break;
968         case ISCSI_KEVENT_CREATE_SESSION:
969                 ev->r.c_session_ret.host_no = shost->host_no;
970                 ev->r.c_session_ret.sid = session->sid;
971                 break;
972         case ISCSI_KEVENT_UNBIND_SESSION:
973                 ev->r.unbind_session.host_no = shost->host_no;
974                 ev->r.unbind_session.sid = session->sid;
975                 break;
976         default:
977                 iscsi_cls_session_printk(KERN_ERR, session, "Invalid event "
978                                          "%u.\n", event);
979                 kfree_skb(skb);
980                 return -EINVAL;
981         }
982
983         /*
984          * this will occur if the daemon is not up, so we just warn
985          * the user and when the daemon is restarted it will handle it
986          */
987         rc = iscsi_broadcast_skb(skb, GFP_KERNEL);
988         if (rc < 0)
989                 iscsi_cls_session_printk(KERN_ERR, session,
990                                          "Cannot notify userspace of session "
991                                          "event %u. Check iscsi daemon\n",
992                                          event);
993         return rc;
994 }
995 EXPORT_SYMBOL_GPL(iscsi_session_event);
996
997 static int
998 iscsi_if_create_session(struct iscsi_internal *priv, struct iscsi_uevent *ev)
999 {
1000         struct iscsi_transport *transport = priv->iscsi_transport;
1001         struct iscsi_cls_session *session;
1002         uint32_t hostno;
1003
1004         session = transport->create_session(transport, &priv->t,
1005                                             ev->u.c_session.cmds_max,
1006                                             ev->u.c_session.queue_depth,
1007                                             ev->u.c_session.initial_cmdsn,
1008                                             &hostno);
1009         if (!session)
1010                 return -ENOMEM;
1011
1012         ev->r.c_session_ret.host_no = hostno;
1013         ev->r.c_session_ret.sid = session->sid;
1014         return 0;
1015 }
1016
1017 static int
1018 iscsi_if_create_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1019 {
1020         struct iscsi_cls_conn *conn;
1021         struct iscsi_cls_session *session;
1022
1023         session = iscsi_session_lookup(ev->u.c_conn.sid);
1024         if (!session) {
1025                 printk(KERN_ERR "iscsi: invalid session %d.\n",
1026                        ev->u.c_conn.sid);
1027                 return -EINVAL;
1028         }
1029
1030         conn = transport->create_conn(session, ev->u.c_conn.cid);
1031         if (!conn) {
1032                 iscsi_cls_session_printk(KERN_ERR, session,
1033                                          "couldn't create a new connection.");
1034                 return -ENOMEM;
1035         }
1036
1037         ev->r.c_conn_ret.sid = session->sid;
1038         ev->r.c_conn_ret.cid = conn->cid;
1039         return 0;
1040 }
1041
1042 static int
1043 iscsi_if_destroy_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1044 {
1045         struct iscsi_cls_conn *conn;
1046
1047         conn = iscsi_conn_lookup(ev->u.d_conn.sid, ev->u.d_conn.cid);
1048         if (!conn)
1049                 return -EINVAL;
1050
1051         if (transport->destroy_conn)
1052                 transport->destroy_conn(conn);
1053         return 0;
1054 }
1055
1056 static int
1057 iscsi_set_param(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1058 {
1059         char *data = (char*)ev + sizeof(*ev);
1060         struct iscsi_cls_conn *conn;
1061         struct iscsi_cls_session *session;
1062         int err = 0, value = 0;
1063
1064         session = iscsi_session_lookup(ev->u.set_param.sid);
1065         conn = iscsi_conn_lookup(ev->u.set_param.sid, ev->u.set_param.cid);
1066         if (!conn || !session)
1067                 return -EINVAL;
1068
1069         switch (ev->u.set_param.param) {
1070         case ISCSI_PARAM_SESS_RECOVERY_TMO:
1071                 sscanf(data, "%d", &value);
1072                 if (value != 0)
1073                         session->recovery_tmo = value;
1074                 break;
1075         default:
1076                 err = transport->set_param(conn, ev->u.set_param.param,
1077                                            data, ev->u.set_param.len);
1078         }
1079
1080         return err;
1081 }
1082
1083 static int
1084 iscsi_if_transport_ep(struct iscsi_transport *transport,
1085                       struct iscsi_uevent *ev, int msg_type)
1086 {
1087         struct sockaddr *dst_addr;
1088         int rc = 0;
1089
1090         switch (msg_type) {
1091         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1092                 if (!transport->ep_connect)
1093                         return -EINVAL;
1094
1095                 dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1096                 rc = transport->ep_connect(dst_addr,
1097                                            ev->u.ep_connect.non_blocking,
1098                                            &ev->r.ep_connect_ret.handle);
1099                 break;
1100         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1101                 if (!transport->ep_poll)
1102                         return -EINVAL;
1103
1104                 ev->r.retcode = transport->ep_poll(ev->u.ep_poll.ep_handle,
1105                                                    ev->u.ep_poll.timeout_ms);
1106                 break;
1107         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1108                 if (!transport->ep_disconnect)
1109                         return -EINVAL;
1110
1111                 transport->ep_disconnect(ev->u.ep_disconnect.ep_handle);
1112                 break;
1113         }
1114         return rc;
1115 }
1116
1117 static int
1118 iscsi_tgt_dscvr(struct iscsi_transport *transport,
1119                 struct iscsi_uevent *ev)
1120 {
1121         struct Scsi_Host *shost;
1122         struct sockaddr *dst_addr;
1123         int err;
1124
1125         if (!transport->tgt_dscvr)
1126                 return -EINVAL;
1127
1128         shost = scsi_host_lookup(ev->u.tgt_dscvr.host_no);
1129         if (IS_ERR(shost)) {
1130                 printk(KERN_ERR "target discovery could not find host no %u\n",
1131                        ev->u.tgt_dscvr.host_no);
1132                 return -ENODEV;
1133         }
1134
1135
1136         dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1137         err = transport->tgt_dscvr(shost, ev->u.tgt_dscvr.type,
1138                                    ev->u.tgt_dscvr.enable, dst_addr);
1139         scsi_host_put(shost);
1140         return err;
1141 }
1142
1143 static int
1144 iscsi_set_host_param(struct iscsi_transport *transport,
1145                      struct iscsi_uevent *ev)
1146 {
1147         char *data = (char*)ev + sizeof(*ev);
1148         struct Scsi_Host *shost;
1149         int err;
1150
1151         if (!transport->set_host_param)
1152                 return -ENOSYS;
1153
1154         shost = scsi_host_lookup(ev->u.set_host_param.host_no);
1155         if (IS_ERR(shost)) {
1156                 printk(KERN_ERR "set_host_param could not find host no %u\n",
1157                        ev->u.set_host_param.host_no);
1158                 return -ENODEV;
1159         }
1160
1161         err = transport->set_host_param(shost, ev->u.set_host_param.param,
1162                                         data, ev->u.set_host_param.len);
1163         scsi_host_put(shost);
1164         return err;
1165 }
1166
1167 static int
1168 iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
1169 {
1170         int err = 0;
1171         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1172         struct iscsi_transport *transport = NULL;
1173         struct iscsi_internal *priv;
1174         struct iscsi_cls_session *session;
1175         struct iscsi_cls_conn *conn;
1176
1177         priv = iscsi_if_transport_lookup(iscsi_ptr(ev->transport_handle));
1178         if (!priv)
1179                 return -EINVAL;
1180         transport = priv->iscsi_transport;
1181
1182         if (!try_module_get(transport->owner))
1183                 return -EINVAL;
1184
1185         priv->daemon_pid = NETLINK_CREDS(skb)->pid;
1186
1187         switch (nlh->nlmsg_type) {
1188         case ISCSI_UEVENT_CREATE_SESSION:
1189                 err = iscsi_if_create_session(priv, ev);
1190                 break;
1191         case ISCSI_UEVENT_DESTROY_SESSION:
1192                 session = iscsi_session_lookup(ev->u.d_session.sid);
1193                 if (session)
1194                         transport->destroy_session(session);
1195                 else
1196                         err = -EINVAL;
1197                 break;
1198         case ISCSI_UEVENT_UNBIND_SESSION:
1199                 session = iscsi_session_lookup(ev->u.d_session.sid);
1200                 if (session)
1201                         iscsi_unbind_session(session);
1202                 else
1203                         err = -EINVAL;
1204                 break;
1205         case ISCSI_UEVENT_CREATE_CONN:
1206                 err = iscsi_if_create_conn(transport, ev);
1207                 break;
1208         case ISCSI_UEVENT_DESTROY_CONN:
1209                 err = iscsi_if_destroy_conn(transport, ev);
1210                 break;
1211         case ISCSI_UEVENT_BIND_CONN:
1212                 session = iscsi_session_lookup(ev->u.b_conn.sid);
1213                 conn = iscsi_conn_lookup(ev->u.b_conn.sid, ev->u.b_conn.cid);
1214
1215                 if (session && conn)
1216                         ev->r.retcode = transport->bind_conn(session, conn,
1217                                         ev->u.b_conn.transport_eph,
1218                                         ev->u.b_conn.is_leading);
1219                 else
1220                         err = -EINVAL;
1221                 break;
1222         case ISCSI_UEVENT_SET_PARAM:
1223                 err = iscsi_set_param(transport, ev);
1224                 break;
1225         case ISCSI_UEVENT_START_CONN:
1226                 conn = iscsi_conn_lookup(ev->u.start_conn.sid, ev->u.start_conn.cid);
1227                 if (conn)
1228                         ev->r.retcode = transport->start_conn(conn);
1229                 else
1230                         err = -EINVAL;
1231                 break;
1232         case ISCSI_UEVENT_STOP_CONN:
1233                 conn = iscsi_conn_lookup(ev->u.stop_conn.sid, ev->u.stop_conn.cid);
1234                 if (conn)
1235                         transport->stop_conn(conn, ev->u.stop_conn.flag);
1236                 else
1237                         err = -EINVAL;
1238                 break;
1239         case ISCSI_UEVENT_SEND_PDU:
1240                 conn = iscsi_conn_lookup(ev->u.send_pdu.sid, ev->u.send_pdu.cid);
1241                 if (conn)
1242                         ev->r.retcode = transport->send_pdu(conn,
1243                                 (struct iscsi_hdr*)((char*)ev + sizeof(*ev)),
1244                                 (char*)ev + sizeof(*ev) + ev->u.send_pdu.hdr_size,
1245                                 ev->u.send_pdu.data_size);
1246                 else
1247                         err = -EINVAL;
1248                 break;
1249         case ISCSI_UEVENT_GET_STATS:
1250                 err = iscsi_if_get_stats(transport, nlh);
1251                 break;
1252         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1253         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1254         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1255                 err = iscsi_if_transport_ep(transport, ev, nlh->nlmsg_type);
1256                 break;
1257         case ISCSI_UEVENT_TGT_DSCVR:
1258                 err = iscsi_tgt_dscvr(transport, ev);
1259                 break;
1260         case ISCSI_UEVENT_SET_HOST_PARAM:
1261                 err = iscsi_set_host_param(transport, ev);
1262                 break;
1263         default:
1264                 err = -ENOSYS;
1265                 break;
1266         }
1267
1268         module_put(transport->owner);
1269         return err;
1270 }
1271
1272 /*
1273  * Get message from skb.  Each message is processed by iscsi_if_recv_msg.
1274  * Malformed skbs with wrong lengths or invalid creds are not processed.
1275  */
1276 static void
1277 iscsi_if_rx(struct sk_buff *skb)
1278 {
1279         mutex_lock(&rx_queue_mutex);
1280         while (skb->len >= NLMSG_SPACE(0)) {
1281                 int err;
1282                 uint32_t rlen;
1283                 struct nlmsghdr *nlh;
1284                 struct iscsi_uevent *ev;
1285
1286                 nlh = nlmsg_hdr(skb);
1287                 if (nlh->nlmsg_len < sizeof(*nlh) ||
1288                     skb->len < nlh->nlmsg_len) {
1289                         break;
1290                 }
1291
1292                 ev = NLMSG_DATA(nlh);
1293                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1294                 if (rlen > skb->len)
1295                         rlen = skb->len;
1296
1297                 err = iscsi_if_recv_msg(skb, nlh);
1298                 if (err) {
1299                         ev->type = ISCSI_KEVENT_IF_ERROR;
1300                         ev->iferror = err;
1301                 }
1302                 do {
1303                         /*
1304                          * special case for GET_STATS:
1305                          * on success - sending reply and stats from
1306                          * inside of if_recv_msg(),
1307                          * on error - fall through.
1308                          */
1309                         if (ev->type == ISCSI_UEVENT_GET_STATS && !err)
1310                                 break;
1311                         err = iscsi_if_send_reply(
1312                                 NETLINK_CREDS(skb)->pid, nlh->nlmsg_seq,
1313                                 nlh->nlmsg_type, 0, 0, ev, sizeof(*ev));
1314                 } while (err < 0 && err != -ECONNREFUSED);
1315                 skb_pull(skb, rlen);
1316         }
1317         mutex_unlock(&rx_queue_mutex);
1318 }
1319
1320 #define iscsi_cdev_to_conn(_cdev) \
1321         iscsi_dev_to_conn(_cdev->dev)
1322
1323 #define ISCSI_CLASS_ATTR(_prefix,_name,_mode,_show,_store)              \
1324 struct class_device_attribute class_device_attr_##_prefix##_##_name =   \
1325         __ATTR(_name,_mode,_show,_store)
1326
1327 /*
1328  * iSCSI connection attrs
1329  */
1330 #define iscsi_conn_attr_show(param)                                     \
1331 static ssize_t                                                          \
1332 show_conn_param_##param(struct class_device *cdev, char *buf)           \
1333 {                                                                       \
1334         struct iscsi_cls_conn *conn = iscsi_cdev_to_conn(cdev);         \
1335         struct iscsi_transport *t = conn->transport;                    \
1336         return t->get_conn_param(conn, param, buf);                     \
1337 }
1338
1339 #define iscsi_conn_attr(field, param)                                   \
1340         iscsi_conn_attr_show(param)                                     \
1341 static ISCSI_CLASS_ATTR(conn, field, S_IRUGO, show_conn_param_##param,  \
1342                         NULL);
1343
1344 iscsi_conn_attr(max_recv_dlength, ISCSI_PARAM_MAX_RECV_DLENGTH);
1345 iscsi_conn_attr(max_xmit_dlength, ISCSI_PARAM_MAX_XMIT_DLENGTH);
1346 iscsi_conn_attr(header_digest, ISCSI_PARAM_HDRDGST_EN);
1347 iscsi_conn_attr(data_digest, ISCSI_PARAM_DATADGST_EN);
1348 iscsi_conn_attr(ifmarker, ISCSI_PARAM_IFMARKER_EN);
1349 iscsi_conn_attr(ofmarker, ISCSI_PARAM_OFMARKER_EN);
1350 iscsi_conn_attr(persistent_port, ISCSI_PARAM_PERSISTENT_PORT);
1351 iscsi_conn_attr(port, ISCSI_PARAM_CONN_PORT);
1352 iscsi_conn_attr(exp_statsn, ISCSI_PARAM_EXP_STATSN);
1353 iscsi_conn_attr(persistent_address, ISCSI_PARAM_PERSISTENT_ADDRESS);
1354 iscsi_conn_attr(address, ISCSI_PARAM_CONN_ADDRESS);
1355 iscsi_conn_attr(ping_tmo, ISCSI_PARAM_PING_TMO);
1356 iscsi_conn_attr(recv_tmo, ISCSI_PARAM_RECV_TMO);
1357
1358 #define iscsi_cdev_to_session(_cdev) \
1359         iscsi_dev_to_session(_cdev->dev)
1360
1361 /*
1362  * iSCSI session attrs
1363  */
1364 #define iscsi_session_attr_show(param, perm)                            \
1365 static ssize_t                                                          \
1366 show_session_param_##param(struct class_device *cdev, char *buf)        \
1367 {                                                                       \
1368         struct iscsi_cls_session *session = iscsi_cdev_to_session(cdev); \
1369         struct iscsi_transport *t = session->transport;                 \
1370                                                                         \
1371         if (perm && !capable(CAP_SYS_ADMIN))                            \
1372                 return -EACCES;                                         \
1373         return t->get_session_param(session, param, buf);               \
1374 }
1375
1376 #define iscsi_session_attr(field, param, perm)                          \
1377         iscsi_session_attr_show(param, perm)                            \
1378 static ISCSI_CLASS_ATTR(sess, field, S_IRUGO, show_session_param_##param, \
1379                         NULL);
1380
1381 iscsi_session_attr(targetname, ISCSI_PARAM_TARGET_NAME, 0);
1382 iscsi_session_attr(initial_r2t, ISCSI_PARAM_INITIAL_R2T_EN, 0);
1383 iscsi_session_attr(max_outstanding_r2t, ISCSI_PARAM_MAX_R2T, 0);
1384 iscsi_session_attr(immediate_data, ISCSI_PARAM_IMM_DATA_EN, 0);
1385 iscsi_session_attr(first_burst_len, ISCSI_PARAM_FIRST_BURST, 0);
1386 iscsi_session_attr(max_burst_len, ISCSI_PARAM_MAX_BURST, 0);
1387 iscsi_session_attr(data_pdu_in_order, ISCSI_PARAM_PDU_INORDER_EN, 0);
1388 iscsi_session_attr(data_seq_in_order, ISCSI_PARAM_DATASEQ_INORDER_EN, 0);
1389 iscsi_session_attr(erl, ISCSI_PARAM_ERL, 0);
1390 iscsi_session_attr(tpgt, ISCSI_PARAM_TPGT, 0);
1391 iscsi_session_attr(username, ISCSI_PARAM_USERNAME, 1);
1392 iscsi_session_attr(username_in, ISCSI_PARAM_USERNAME_IN, 1);
1393 iscsi_session_attr(password, ISCSI_PARAM_PASSWORD, 1);
1394 iscsi_session_attr(password_in, ISCSI_PARAM_PASSWORD_IN, 1);
1395 iscsi_session_attr(fast_abort, ISCSI_PARAM_FAST_ABORT, 0);
1396 iscsi_session_attr(abort_tmo, ISCSI_PARAM_ABORT_TMO, 0);
1397 iscsi_session_attr(lu_reset_tmo, ISCSI_PARAM_LU_RESET_TMO, 0);
1398
1399 static ssize_t
1400 show_priv_session_state(struct class_device *cdev, char *buf)
1401 {
1402         struct iscsi_cls_session *session = iscsi_cdev_to_session(cdev);
1403         return sprintf(buf, "%s\n", iscsi_session_state_name(session->state));
1404 }
1405 static ISCSI_CLASS_ATTR(priv_sess, state, S_IRUGO, show_priv_session_state,
1406                         NULL);
1407
1408 #define iscsi_priv_session_attr_show(field, format)                     \
1409 static ssize_t                                                          \
1410 show_priv_session_##field(struct class_device *cdev, char *buf)         \
1411 {                                                                       \
1412         struct iscsi_cls_session *session = iscsi_cdev_to_session(cdev);\
1413         return sprintf(buf, format"\n", session->field);                \
1414 }
1415
1416 #define iscsi_priv_session_attr(field, format)                          \
1417         iscsi_priv_session_attr_show(field, format)                     \
1418 static ISCSI_CLASS_ATTR(priv_sess, field, S_IRUGO, show_priv_session_##field, \
1419                         NULL)
1420 iscsi_priv_session_attr(recovery_tmo, "%d");
1421
1422 /*
1423  * iSCSI host attrs
1424  */
1425 #define iscsi_host_attr_show(param)                                     \
1426 static ssize_t                                                          \
1427 show_host_param_##param(struct class_device *cdev, char *buf)           \
1428 {                                                                       \
1429         struct Scsi_Host *shost = transport_class_to_shost(cdev);       \
1430         struct iscsi_internal *priv = to_iscsi_internal(shost->transportt); \
1431         return priv->iscsi_transport->get_host_param(shost, param, buf); \
1432 }
1433
1434 #define iscsi_host_attr(field, param)                                   \
1435         iscsi_host_attr_show(param)                                     \
1436 static ISCSI_CLASS_ATTR(host, field, S_IRUGO, show_host_param_##param,  \
1437                         NULL);
1438
1439 iscsi_host_attr(netdev, ISCSI_HOST_PARAM_NETDEV_NAME);
1440 iscsi_host_attr(hwaddress, ISCSI_HOST_PARAM_HWADDRESS);
1441 iscsi_host_attr(ipaddress, ISCSI_HOST_PARAM_IPADDRESS);
1442 iscsi_host_attr(initiatorname, ISCSI_HOST_PARAM_INITIATOR_NAME);
1443
1444 #define SETUP_PRIV_SESSION_RD_ATTR(field)                               \
1445 do {                                                                    \
1446         priv->session_attrs[count] = &class_device_attr_priv_sess_##field; \
1447         count++;                                                        \
1448 } while (0)
1449
1450
1451 #define SETUP_SESSION_RD_ATTR(field, param_flag)                        \
1452 do {                                                                    \
1453         if (tt->param_mask & param_flag) {                              \
1454                 priv->session_attrs[count] = &class_device_attr_sess_##field; \
1455                 count++;                                                \
1456         }                                                               \
1457 } while (0)
1458
1459 #define SETUP_CONN_RD_ATTR(field, param_flag)                           \
1460 do {                                                                    \
1461         if (tt->param_mask & param_flag) {                              \
1462                 priv->conn_attrs[count] = &class_device_attr_conn_##field; \
1463                 count++;                                                \
1464         }                                                               \
1465 } while (0)
1466
1467 #define SETUP_HOST_RD_ATTR(field, param_flag)                           \
1468 do {                                                                    \
1469         if (tt->host_param_mask & param_flag) {                         \
1470                 priv->host_attrs[count] = &class_device_attr_host_##field; \
1471                 count++;                                                \
1472         }                                                               \
1473 } while (0)
1474
1475 static int iscsi_session_match(struct attribute_container *cont,
1476                            struct device *dev)
1477 {
1478         struct iscsi_cls_session *session;
1479         struct Scsi_Host *shost;
1480         struct iscsi_internal *priv;
1481
1482         if (!iscsi_is_session_dev(dev))
1483                 return 0;
1484
1485         session = iscsi_dev_to_session(dev);
1486         shost = iscsi_session_to_shost(session);
1487         if (!shost->transportt)
1488                 return 0;
1489
1490         priv = to_iscsi_internal(shost->transportt);
1491         if (priv->session_cont.ac.class != &iscsi_session_class.class)
1492                 return 0;
1493
1494         return &priv->session_cont.ac == cont;
1495 }
1496
1497 static int iscsi_conn_match(struct attribute_container *cont,
1498                            struct device *dev)
1499 {
1500         struct iscsi_cls_session *session;
1501         struct iscsi_cls_conn *conn;
1502         struct Scsi_Host *shost;
1503         struct iscsi_internal *priv;
1504
1505         if (!iscsi_is_conn_dev(dev))
1506                 return 0;
1507
1508         conn = iscsi_dev_to_conn(dev);
1509         session = iscsi_dev_to_session(conn->dev.parent);
1510         shost = iscsi_session_to_shost(session);
1511
1512         if (!shost->transportt)
1513                 return 0;
1514
1515         priv = to_iscsi_internal(shost->transportt);
1516         if (priv->conn_cont.ac.class != &iscsi_connection_class.class)
1517                 return 0;
1518
1519         return &priv->conn_cont.ac == cont;
1520 }
1521
1522 static int iscsi_host_match(struct attribute_container *cont,
1523                             struct device *dev)
1524 {
1525         struct Scsi_Host *shost;
1526         struct iscsi_internal *priv;
1527
1528         if (!scsi_is_host_device(dev))
1529                 return 0;
1530
1531         shost = dev_to_shost(dev);
1532         if (!shost->transportt  ||
1533             shost->transportt->host_attrs.ac.class != &iscsi_host_class.class)
1534                 return 0;
1535
1536         priv = to_iscsi_internal(shost->transportt);
1537         return &priv->t.host_attrs.ac == cont;
1538 }
1539
1540 struct scsi_transport_template *
1541 iscsi_register_transport(struct iscsi_transport *tt)
1542 {
1543         struct iscsi_internal *priv;
1544         unsigned long flags;
1545         int count = 0, err;
1546
1547         BUG_ON(!tt);
1548
1549         priv = iscsi_if_transport_lookup(tt);
1550         if (priv)
1551                 return NULL;
1552
1553         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1554         if (!priv)
1555                 return NULL;
1556         INIT_LIST_HEAD(&priv->list);
1557         priv->daemon_pid = -1;
1558         priv->iscsi_transport = tt;
1559         priv->t.user_scan = iscsi_user_scan;
1560
1561         priv->cdev.class = &iscsi_transport_class;
1562         snprintf(priv->cdev.class_id, BUS_ID_SIZE, "%s", tt->name);
1563         err = class_device_register(&priv->cdev);
1564         if (err)
1565                 goto free_priv;
1566
1567         err = sysfs_create_group(&priv->cdev.kobj, &iscsi_transport_group);
1568         if (err)
1569                 goto unregister_cdev;
1570
1571         /* host parameters */
1572         priv->t.host_attrs.ac.attrs = &priv->host_attrs[0];
1573         priv->t.host_attrs.ac.class = &iscsi_host_class.class;
1574         priv->t.host_attrs.ac.match = iscsi_host_match;
1575         priv->t.host_size = sizeof(struct iscsi_host);
1576         transport_container_register(&priv->t.host_attrs);
1577
1578         SETUP_HOST_RD_ATTR(netdev, ISCSI_HOST_NETDEV_NAME);
1579         SETUP_HOST_RD_ATTR(ipaddress, ISCSI_HOST_IPADDRESS);
1580         SETUP_HOST_RD_ATTR(hwaddress, ISCSI_HOST_HWADDRESS);
1581         SETUP_HOST_RD_ATTR(initiatorname, ISCSI_HOST_INITIATOR_NAME);
1582         BUG_ON(count > ISCSI_HOST_ATTRS);
1583         priv->host_attrs[count] = NULL;
1584         count = 0;
1585
1586         /* connection parameters */
1587         priv->conn_cont.ac.attrs = &priv->conn_attrs[0];
1588         priv->conn_cont.ac.class = &iscsi_connection_class.class;
1589         priv->conn_cont.ac.match = iscsi_conn_match;
1590         transport_container_register(&priv->conn_cont);
1591
1592         SETUP_CONN_RD_ATTR(max_recv_dlength, ISCSI_MAX_RECV_DLENGTH);
1593         SETUP_CONN_RD_ATTR(max_xmit_dlength, ISCSI_MAX_XMIT_DLENGTH);
1594         SETUP_CONN_RD_ATTR(header_digest, ISCSI_HDRDGST_EN);
1595         SETUP_CONN_RD_ATTR(data_digest, ISCSI_DATADGST_EN);
1596         SETUP_CONN_RD_ATTR(ifmarker, ISCSI_IFMARKER_EN);
1597         SETUP_CONN_RD_ATTR(ofmarker, ISCSI_OFMARKER_EN);
1598         SETUP_CONN_RD_ATTR(address, ISCSI_CONN_ADDRESS);
1599         SETUP_CONN_RD_ATTR(port, ISCSI_CONN_PORT);
1600         SETUP_CONN_RD_ATTR(exp_statsn, ISCSI_EXP_STATSN);
1601         SETUP_CONN_RD_ATTR(persistent_address, ISCSI_PERSISTENT_ADDRESS);
1602         SETUP_CONN_RD_ATTR(persistent_port, ISCSI_PERSISTENT_PORT);
1603         SETUP_CONN_RD_ATTR(ping_tmo, ISCSI_PING_TMO);
1604         SETUP_CONN_RD_ATTR(recv_tmo, ISCSI_RECV_TMO);
1605
1606         BUG_ON(count > ISCSI_CONN_ATTRS);
1607         priv->conn_attrs[count] = NULL;
1608         count = 0;
1609
1610         /* session parameters */
1611         priv->session_cont.ac.attrs = &priv->session_attrs[0];
1612         priv->session_cont.ac.class = &iscsi_session_class.class;
1613         priv->session_cont.ac.match = iscsi_session_match;
1614         transport_container_register(&priv->session_cont);
1615
1616         SETUP_SESSION_RD_ATTR(initial_r2t, ISCSI_INITIAL_R2T_EN);
1617         SETUP_SESSION_RD_ATTR(max_outstanding_r2t, ISCSI_MAX_R2T);
1618         SETUP_SESSION_RD_ATTR(immediate_data, ISCSI_IMM_DATA_EN);
1619         SETUP_SESSION_RD_ATTR(first_burst_len, ISCSI_FIRST_BURST);
1620         SETUP_SESSION_RD_ATTR(max_burst_len, ISCSI_MAX_BURST);
1621         SETUP_SESSION_RD_ATTR(data_pdu_in_order, ISCSI_PDU_INORDER_EN);
1622         SETUP_SESSION_RD_ATTR(data_seq_in_order, ISCSI_DATASEQ_INORDER_EN);
1623         SETUP_SESSION_RD_ATTR(erl, ISCSI_ERL);
1624         SETUP_SESSION_RD_ATTR(targetname, ISCSI_TARGET_NAME);
1625         SETUP_SESSION_RD_ATTR(tpgt, ISCSI_TPGT);
1626         SETUP_SESSION_RD_ATTR(password, ISCSI_USERNAME);
1627         SETUP_SESSION_RD_ATTR(password_in, ISCSI_USERNAME_IN);
1628         SETUP_SESSION_RD_ATTR(username, ISCSI_PASSWORD);
1629         SETUP_SESSION_RD_ATTR(username_in, ISCSI_PASSWORD_IN);
1630         SETUP_SESSION_RD_ATTR(fast_abort, ISCSI_FAST_ABORT);
1631         SETUP_SESSION_RD_ATTR(abort_tmo, ISCSI_ABORT_TMO);
1632         SETUP_SESSION_RD_ATTR(lu_reset_tmo,ISCSI_LU_RESET_TMO);
1633         SETUP_PRIV_SESSION_RD_ATTR(recovery_tmo);
1634         SETUP_PRIV_SESSION_RD_ATTR(state);
1635
1636         BUG_ON(count > ISCSI_SESSION_ATTRS);
1637         priv->session_attrs[count] = NULL;
1638
1639         spin_lock_irqsave(&iscsi_transport_lock, flags);
1640         list_add(&priv->list, &iscsi_transports);
1641         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1642
1643         printk(KERN_NOTICE "iscsi: registered transport (%s)\n", tt->name);
1644         return &priv->t;
1645
1646 unregister_cdev:
1647         class_device_unregister(&priv->cdev);
1648 free_priv:
1649         kfree(priv);
1650         return NULL;
1651 }
1652 EXPORT_SYMBOL_GPL(iscsi_register_transport);
1653
1654 int iscsi_unregister_transport(struct iscsi_transport *tt)
1655 {
1656         struct iscsi_internal *priv;
1657         unsigned long flags;
1658
1659         BUG_ON(!tt);
1660
1661         mutex_lock(&rx_queue_mutex);
1662
1663         priv = iscsi_if_transport_lookup(tt);
1664         BUG_ON (!priv);
1665
1666         spin_lock_irqsave(&iscsi_transport_lock, flags);
1667         list_del(&priv->list);
1668         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1669
1670         transport_container_unregister(&priv->conn_cont);
1671         transport_container_unregister(&priv->session_cont);
1672         transport_container_unregister(&priv->t.host_attrs);
1673
1674         sysfs_remove_group(&priv->cdev.kobj, &iscsi_transport_group);
1675         class_device_unregister(&priv->cdev);
1676         mutex_unlock(&rx_queue_mutex);
1677
1678         return 0;
1679 }
1680 EXPORT_SYMBOL_GPL(iscsi_unregister_transport);
1681
1682 static __init int iscsi_transport_init(void)
1683 {
1684         int err;
1685
1686         printk(KERN_INFO "Loading iSCSI transport class v%s.\n",
1687                 ISCSI_TRANSPORT_VERSION);
1688
1689         atomic_set(&iscsi_session_nr, 0);
1690
1691         err = class_register(&iscsi_transport_class);
1692         if (err)
1693                 return err;
1694
1695         err = transport_class_register(&iscsi_host_class);
1696         if (err)
1697                 goto unregister_transport_class;
1698
1699         err = transport_class_register(&iscsi_connection_class);
1700         if (err)
1701                 goto unregister_host_class;
1702
1703         err = transport_class_register(&iscsi_session_class);
1704         if (err)
1705                 goto unregister_conn_class;
1706
1707         nls = netlink_kernel_create(&init_net, NETLINK_ISCSI, 1, iscsi_if_rx, NULL,
1708                         THIS_MODULE);
1709         if (!nls) {
1710                 err = -ENOBUFS;
1711                 goto unregister_session_class;
1712         }
1713
1714         iscsi_eh_timer_workq = create_singlethread_workqueue("iscsi_eh");
1715         if (!iscsi_eh_timer_workq)
1716                 goto release_nls;
1717
1718         return 0;
1719
1720 release_nls:
1721         netlink_kernel_release(nls);
1722 unregister_session_class:
1723         transport_class_unregister(&iscsi_session_class);
1724 unregister_conn_class:
1725         transport_class_unregister(&iscsi_connection_class);
1726 unregister_host_class:
1727         transport_class_unregister(&iscsi_host_class);
1728 unregister_transport_class:
1729         class_unregister(&iscsi_transport_class);
1730         return err;
1731 }
1732
1733 static void __exit iscsi_transport_exit(void)
1734 {
1735         destroy_workqueue(iscsi_eh_timer_workq);
1736         netlink_kernel_release(nls);
1737         transport_class_unregister(&iscsi_connection_class);
1738         transport_class_unregister(&iscsi_session_class);
1739         transport_class_unregister(&iscsi_host_class);
1740         class_unregister(&iscsi_transport_class);
1741 }
1742
1743 module_init(iscsi_transport_init);
1744 module_exit(iscsi_transport_exit);
1745
1746 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
1747               "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
1748               "Alex Aizman <itn780@yahoo.com>");
1749 MODULE_DESCRIPTION("iSCSI Transport Interface");
1750 MODULE_LICENSE("GPL");
1751 MODULE_VERSION(ISCSI_TRANSPORT_VERSION);