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