Merge branch 'topic/hdsp' into for-linus
[pandora-kernel.git] / 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_IMM_RETRY << 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         return netlink_broadcast(nls, skb, 0, 1, gfp);
944 }
945
946 static int
947 iscsi_unicast_skb(struct sk_buff *skb, int pid)
948 {
949         int rc;
950
951         rc = netlink_unicast(nls, skb, pid, MSG_DONTWAIT);
952         if (rc < 0) {
953                 printk(KERN_ERR "iscsi: can not unicast skb (%d)\n", rc);
954                 return rc;
955         }
956
957         return 0;
958 }
959
960 int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
961                    char *data, uint32_t data_size)
962 {
963         struct nlmsghdr *nlh;
964         struct sk_buff *skb;
965         struct iscsi_uevent *ev;
966         char *pdu;
967         struct iscsi_internal *priv;
968         int len = NLMSG_SPACE(sizeof(*ev) + sizeof(struct iscsi_hdr) +
969                               data_size);
970
971         priv = iscsi_if_transport_lookup(conn->transport);
972         if (!priv)
973                 return -EINVAL;
974
975         skb = alloc_skb(len, GFP_ATOMIC);
976         if (!skb) {
977                 iscsi_conn_error_event(conn, ISCSI_ERR_CONN_FAILED);
978                 iscsi_cls_conn_printk(KERN_ERR, conn, "can not deliver "
979                                       "control PDU: OOM\n");
980                 return -ENOMEM;
981         }
982
983         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
984         ev = NLMSG_DATA(nlh);
985         memset(ev, 0, sizeof(*ev));
986         ev->transport_handle = iscsi_handle(conn->transport);
987         ev->type = ISCSI_KEVENT_RECV_PDU;
988         ev->r.recv_req.cid = conn->cid;
989         ev->r.recv_req.sid = iscsi_conn_get_sid(conn);
990         pdu = (char*)ev + sizeof(*ev);
991         memcpy(pdu, hdr, sizeof(struct iscsi_hdr));
992         memcpy(pdu + sizeof(struct iscsi_hdr), data, data_size);
993
994         return iscsi_unicast_skb(skb, priv->daemon_pid);
995 }
996 EXPORT_SYMBOL_GPL(iscsi_recv_pdu);
997
998 void iscsi_conn_error_event(struct iscsi_cls_conn *conn, enum iscsi_err error)
999 {
1000         struct nlmsghdr *nlh;
1001         struct sk_buff  *skb;
1002         struct iscsi_uevent *ev;
1003         struct iscsi_internal *priv;
1004         int len = NLMSG_SPACE(sizeof(*ev));
1005
1006         priv = iscsi_if_transport_lookup(conn->transport);
1007         if (!priv)
1008                 return;
1009
1010         skb = alloc_skb(len, GFP_ATOMIC);
1011         if (!skb) {
1012                 iscsi_cls_conn_printk(KERN_ERR, conn, "gracefully ignored "
1013                                       "conn error (%d)\n", error);
1014                 return;
1015         }
1016
1017         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
1018         ev = NLMSG_DATA(nlh);
1019         ev->transport_handle = iscsi_handle(conn->transport);
1020         ev->type = ISCSI_KEVENT_CONN_ERROR;
1021         ev->r.connerror.error = error;
1022         ev->r.connerror.cid = conn->cid;
1023         ev->r.connerror.sid = iscsi_conn_get_sid(conn);
1024
1025         iscsi_broadcast_skb(skb, GFP_ATOMIC);
1026
1027         iscsi_cls_conn_printk(KERN_INFO, conn, "detected conn error (%d)\n",
1028                               error);
1029 }
1030 EXPORT_SYMBOL_GPL(iscsi_conn_error_event);
1031
1032 static int
1033 iscsi_if_send_reply(int pid, int seq, int type, int done, int multi,
1034                       void *payload, int size)
1035 {
1036         struct sk_buff  *skb;
1037         struct nlmsghdr *nlh;
1038         int len = NLMSG_SPACE(size);
1039         int flags = multi ? NLM_F_MULTI : 0;
1040         int t = done ? NLMSG_DONE : type;
1041
1042         skb = alloc_skb(len, GFP_ATOMIC);
1043         if (!skb) {
1044                 printk(KERN_ERR "Could not allocate skb to send reply.\n");
1045                 return -ENOMEM;
1046         }
1047
1048         nlh = __nlmsg_put(skb, pid, seq, t, (len - sizeof(*nlh)), 0);
1049         nlh->nlmsg_flags = flags;
1050         memcpy(NLMSG_DATA(nlh), payload, size);
1051         return iscsi_unicast_skb(skb, pid);
1052 }
1053
1054 static int
1055 iscsi_if_get_stats(struct iscsi_transport *transport, struct nlmsghdr *nlh)
1056 {
1057         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1058         struct iscsi_stats *stats;
1059         struct sk_buff *skbstat;
1060         struct iscsi_cls_conn *conn;
1061         struct nlmsghdr *nlhstat;
1062         struct iscsi_uevent *evstat;
1063         struct iscsi_internal *priv;
1064         int len = NLMSG_SPACE(sizeof(*ev) +
1065                               sizeof(struct iscsi_stats) +
1066                               sizeof(struct iscsi_stats_custom) *
1067                               ISCSI_STATS_CUSTOM_MAX);
1068         int err = 0;
1069
1070         priv = iscsi_if_transport_lookup(transport);
1071         if (!priv)
1072                 return -EINVAL;
1073
1074         conn = iscsi_conn_lookup(ev->u.get_stats.sid, ev->u.get_stats.cid);
1075         if (!conn)
1076                 return -EEXIST;
1077
1078         do {
1079                 int actual_size;
1080
1081                 skbstat = alloc_skb(len, GFP_ATOMIC);
1082                 if (!skbstat) {
1083                         iscsi_cls_conn_printk(KERN_ERR, conn, "can not "
1084                                               "deliver stats: OOM\n");
1085                         return -ENOMEM;
1086                 }
1087
1088                 nlhstat = __nlmsg_put(skbstat, priv->daemon_pid, 0, 0,
1089                                       (len - sizeof(*nlhstat)), 0);
1090                 evstat = NLMSG_DATA(nlhstat);
1091                 memset(evstat, 0, sizeof(*evstat));
1092                 evstat->transport_handle = iscsi_handle(conn->transport);
1093                 evstat->type = nlh->nlmsg_type;
1094                 evstat->u.get_stats.cid =
1095                         ev->u.get_stats.cid;
1096                 evstat->u.get_stats.sid =
1097                         ev->u.get_stats.sid;
1098                 stats = (struct iscsi_stats *)
1099                         ((char*)evstat + sizeof(*evstat));
1100                 memset(stats, 0, sizeof(*stats));
1101
1102                 transport->get_stats(conn, stats);
1103                 actual_size = NLMSG_SPACE(sizeof(struct iscsi_uevent) +
1104                                           sizeof(struct iscsi_stats) +
1105                                           sizeof(struct iscsi_stats_custom) *
1106                                           stats->custom_length);
1107                 actual_size -= sizeof(*nlhstat);
1108                 actual_size = NLMSG_LENGTH(actual_size);
1109                 skb_trim(skbstat, NLMSG_ALIGN(actual_size));
1110                 nlhstat->nlmsg_len = actual_size;
1111
1112                 err = iscsi_unicast_skb(skbstat, priv->daemon_pid);
1113         } while (err < 0 && err != -ECONNREFUSED);
1114
1115         return err;
1116 }
1117
1118 /**
1119  * iscsi_session_event - send session destr. completion event
1120  * @session: iscsi class session
1121  * @event: type of event
1122  */
1123 int iscsi_session_event(struct iscsi_cls_session *session,
1124                         enum iscsi_uevent_e event)
1125 {
1126         struct iscsi_internal *priv;
1127         struct Scsi_Host *shost;
1128         struct iscsi_uevent *ev;
1129         struct sk_buff  *skb;
1130         struct nlmsghdr *nlh;
1131         int rc, len = NLMSG_SPACE(sizeof(*ev));
1132
1133         priv = iscsi_if_transport_lookup(session->transport);
1134         if (!priv)
1135                 return -EINVAL;
1136         shost = iscsi_session_to_shost(session);
1137
1138         skb = alloc_skb(len, GFP_KERNEL);
1139         if (!skb) {
1140                 iscsi_cls_session_printk(KERN_ERR, session,
1141                                          "Cannot notify userspace of session "
1142                                          "event %u\n", event);
1143                 return -ENOMEM;
1144         }
1145
1146         nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
1147         ev = NLMSG_DATA(nlh);
1148         ev->transport_handle = iscsi_handle(session->transport);
1149
1150         ev->type = event;
1151         switch (event) {
1152         case ISCSI_KEVENT_DESTROY_SESSION:
1153                 ev->r.d_session.host_no = shost->host_no;
1154                 ev->r.d_session.sid = session->sid;
1155                 break;
1156         case ISCSI_KEVENT_CREATE_SESSION:
1157                 ev->r.c_session_ret.host_no = shost->host_no;
1158                 ev->r.c_session_ret.sid = session->sid;
1159                 break;
1160         case ISCSI_KEVENT_UNBIND_SESSION:
1161                 ev->r.unbind_session.host_no = shost->host_no;
1162                 ev->r.unbind_session.sid = session->sid;
1163                 break;
1164         default:
1165                 iscsi_cls_session_printk(KERN_ERR, session, "Invalid event "
1166                                          "%u.\n", event);
1167                 kfree_skb(skb);
1168                 return -EINVAL;
1169         }
1170
1171         /*
1172          * this will occur if the daemon is not up, so we just warn
1173          * the user and when the daemon is restarted it will handle it
1174          */
1175         rc = iscsi_broadcast_skb(skb, GFP_KERNEL);
1176         if (rc == -ESRCH)
1177                 iscsi_cls_session_printk(KERN_ERR, session,
1178                                          "Cannot notify userspace of session "
1179                                          "event %u. Check iscsi daemon\n",
1180                                          event);
1181         return rc;
1182 }
1183 EXPORT_SYMBOL_GPL(iscsi_session_event);
1184
1185 static int
1186 iscsi_if_create_session(struct iscsi_internal *priv, struct iscsi_endpoint *ep,
1187                         struct iscsi_uevent *ev, uint32_t initial_cmdsn,
1188                         uint16_t cmds_max, uint16_t queue_depth)
1189 {
1190         struct iscsi_transport *transport = priv->iscsi_transport;
1191         struct iscsi_cls_session *session;
1192         struct Scsi_Host *shost;
1193
1194         session = transport->create_session(ep, cmds_max, queue_depth,
1195                                             initial_cmdsn);
1196         if (!session)
1197                 return -ENOMEM;
1198
1199         shost = iscsi_session_to_shost(session);
1200         ev->r.c_session_ret.host_no = shost->host_no;
1201         ev->r.c_session_ret.sid = session->sid;
1202         return 0;
1203 }
1204
1205 static int
1206 iscsi_if_create_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1207 {
1208         struct iscsi_cls_conn *conn;
1209         struct iscsi_cls_session *session;
1210
1211         session = iscsi_session_lookup(ev->u.c_conn.sid);
1212         if (!session) {
1213                 printk(KERN_ERR "iscsi: invalid session %d.\n",
1214                        ev->u.c_conn.sid);
1215                 return -EINVAL;
1216         }
1217
1218         conn = transport->create_conn(session, ev->u.c_conn.cid);
1219         if (!conn) {
1220                 iscsi_cls_session_printk(KERN_ERR, session,
1221                                          "couldn't create a new connection.");
1222                 return -ENOMEM;
1223         }
1224
1225         ev->r.c_conn_ret.sid = session->sid;
1226         ev->r.c_conn_ret.cid = conn->cid;
1227         return 0;
1228 }
1229
1230 static int
1231 iscsi_if_destroy_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1232 {
1233         struct iscsi_cls_conn *conn;
1234
1235         conn = iscsi_conn_lookup(ev->u.d_conn.sid, ev->u.d_conn.cid);
1236         if (!conn)
1237                 return -EINVAL;
1238
1239         if (transport->destroy_conn)
1240                 transport->destroy_conn(conn);
1241         return 0;
1242 }
1243
1244 static int
1245 iscsi_set_param(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1246 {
1247         char *data = (char*)ev + sizeof(*ev);
1248         struct iscsi_cls_conn *conn;
1249         struct iscsi_cls_session *session;
1250         int err = 0, value = 0;
1251
1252         session = iscsi_session_lookup(ev->u.set_param.sid);
1253         conn = iscsi_conn_lookup(ev->u.set_param.sid, ev->u.set_param.cid);
1254         if (!conn || !session)
1255                 return -EINVAL;
1256
1257         switch (ev->u.set_param.param) {
1258         case ISCSI_PARAM_SESS_RECOVERY_TMO:
1259                 sscanf(data, "%d", &value);
1260                 if (value != 0)
1261                         session->recovery_tmo = value;
1262                 break;
1263         default:
1264                 err = transport->set_param(conn, ev->u.set_param.param,
1265                                            data, ev->u.set_param.len);
1266         }
1267
1268         return err;
1269 }
1270
1271 static int
1272 iscsi_if_transport_ep(struct iscsi_transport *transport,
1273                       struct iscsi_uevent *ev, int msg_type)
1274 {
1275         struct iscsi_endpoint *ep;
1276         struct sockaddr *dst_addr;
1277         int rc = 0;
1278
1279         switch (msg_type) {
1280         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1281                 if (!transport->ep_connect)
1282                         return -EINVAL;
1283
1284                 dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1285                 ep = transport->ep_connect(dst_addr,
1286                                            ev->u.ep_connect.non_blocking);
1287                 if (IS_ERR(ep))
1288                         return PTR_ERR(ep);
1289
1290                 ev->r.ep_connect_ret.handle = ep->id;
1291                 break;
1292         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1293                 if (!transport->ep_poll)
1294                         return -EINVAL;
1295
1296                 ep = iscsi_lookup_endpoint(ev->u.ep_poll.ep_handle);
1297                 if (!ep)
1298                         return -EINVAL;
1299
1300                 ev->r.retcode = transport->ep_poll(ep,
1301                                                    ev->u.ep_poll.timeout_ms);
1302                 break;
1303         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1304                 if (!transport->ep_disconnect)
1305                         return -EINVAL;
1306
1307                 ep = iscsi_lookup_endpoint(ev->u.ep_disconnect.ep_handle);
1308                 if (!ep)
1309                         return -EINVAL;
1310
1311                 transport->ep_disconnect(ep);
1312                 break;
1313         }
1314         return rc;
1315 }
1316
1317 static int
1318 iscsi_tgt_dscvr(struct iscsi_transport *transport,
1319                 struct iscsi_uevent *ev)
1320 {
1321         struct Scsi_Host *shost;
1322         struct sockaddr *dst_addr;
1323         int err;
1324
1325         if (!transport->tgt_dscvr)
1326                 return -EINVAL;
1327
1328         shost = scsi_host_lookup(ev->u.tgt_dscvr.host_no);
1329         if (!shost) {
1330                 printk(KERN_ERR "target discovery could not find host no %u\n",
1331                        ev->u.tgt_dscvr.host_no);
1332                 return -ENODEV;
1333         }
1334
1335
1336         dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1337         err = transport->tgt_dscvr(shost, ev->u.tgt_dscvr.type,
1338                                    ev->u.tgt_dscvr.enable, dst_addr);
1339         scsi_host_put(shost);
1340         return err;
1341 }
1342
1343 static int
1344 iscsi_set_host_param(struct iscsi_transport *transport,
1345                      struct iscsi_uevent *ev)
1346 {
1347         char *data = (char*)ev + sizeof(*ev);
1348         struct Scsi_Host *shost;
1349         int err;
1350
1351         if (!transport->set_host_param)
1352                 return -ENOSYS;
1353
1354         shost = scsi_host_lookup(ev->u.set_host_param.host_no);
1355         if (!shost) {
1356                 printk(KERN_ERR "set_host_param could not find host no %u\n",
1357                        ev->u.set_host_param.host_no);
1358                 return -ENODEV;
1359         }
1360
1361         err = transport->set_host_param(shost, ev->u.set_host_param.param,
1362                                         data, ev->u.set_host_param.len);
1363         scsi_host_put(shost);
1364         return err;
1365 }
1366
1367 static int
1368 iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
1369 {
1370         int err = 0;
1371         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1372         struct iscsi_transport *transport = NULL;
1373         struct iscsi_internal *priv;
1374         struct iscsi_cls_session *session;
1375         struct iscsi_cls_conn *conn;
1376         struct iscsi_endpoint *ep = NULL;
1377
1378         priv = iscsi_if_transport_lookup(iscsi_ptr(ev->transport_handle));
1379         if (!priv)
1380                 return -EINVAL;
1381         transport = priv->iscsi_transport;
1382
1383         if (!try_module_get(transport->owner))
1384                 return -EINVAL;
1385
1386         priv->daemon_pid = NETLINK_CREDS(skb)->pid;
1387
1388         switch (nlh->nlmsg_type) {
1389         case ISCSI_UEVENT_CREATE_SESSION:
1390                 err = iscsi_if_create_session(priv, ep, ev,
1391                                               ev->u.c_session.initial_cmdsn,
1392                                               ev->u.c_session.cmds_max,
1393                                               ev->u.c_session.queue_depth);
1394                 break;
1395         case ISCSI_UEVENT_CREATE_BOUND_SESSION:
1396                 ep = iscsi_lookup_endpoint(ev->u.c_bound_session.ep_handle);
1397                 if (!ep) {
1398                         err = -EINVAL;
1399                         break;
1400                 }
1401
1402                 err = iscsi_if_create_session(priv, ep, ev,
1403                                         ev->u.c_bound_session.initial_cmdsn,
1404                                         ev->u.c_bound_session.cmds_max,
1405                                         ev->u.c_bound_session.queue_depth);
1406                 break;
1407         case ISCSI_UEVENT_DESTROY_SESSION:
1408                 session = iscsi_session_lookup(ev->u.d_session.sid);
1409                 if (session)
1410                         transport->destroy_session(session);
1411                 else
1412                         err = -EINVAL;
1413                 break;
1414         case ISCSI_UEVENT_UNBIND_SESSION:
1415                 session = iscsi_session_lookup(ev->u.d_session.sid);
1416                 if (session)
1417                         scsi_queue_work(iscsi_session_to_shost(session),
1418                                         &session->unbind_work);
1419                 else
1420                         err = -EINVAL;
1421                 break;
1422         case ISCSI_UEVENT_CREATE_CONN:
1423                 err = iscsi_if_create_conn(transport, ev);
1424                 break;
1425         case ISCSI_UEVENT_DESTROY_CONN:
1426                 err = iscsi_if_destroy_conn(transport, ev);
1427                 break;
1428         case ISCSI_UEVENT_BIND_CONN:
1429                 session = iscsi_session_lookup(ev->u.b_conn.sid);
1430                 conn = iscsi_conn_lookup(ev->u.b_conn.sid, ev->u.b_conn.cid);
1431
1432                 if (session && conn)
1433                         ev->r.retcode = transport->bind_conn(session, conn,
1434                                         ev->u.b_conn.transport_eph,
1435                                         ev->u.b_conn.is_leading);
1436                 else
1437                         err = -EINVAL;
1438                 break;
1439         case ISCSI_UEVENT_SET_PARAM:
1440                 err = iscsi_set_param(transport, ev);
1441                 break;
1442         case ISCSI_UEVENT_START_CONN:
1443                 conn = iscsi_conn_lookup(ev->u.start_conn.sid, ev->u.start_conn.cid);
1444                 if (conn)
1445                         ev->r.retcode = transport->start_conn(conn);
1446                 else
1447                         err = -EINVAL;
1448                 break;
1449         case ISCSI_UEVENT_STOP_CONN:
1450                 conn = iscsi_conn_lookup(ev->u.stop_conn.sid, ev->u.stop_conn.cid);
1451                 if (conn)
1452                         transport->stop_conn(conn, ev->u.stop_conn.flag);
1453                 else
1454                         err = -EINVAL;
1455                 break;
1456         case ISCSI_UEVENT_SEND_PDU:
1457                 conn = iscsi_conn_lookup(ev->u.send_pdu.sid, ev->u.send_pdu.cid);
1458                 if (conn)
1459                         ev->r.retcode = transport->send_pdu(conn,
1460                                 (struct iscsi_hdr*)((char*)ev + sizeof(*ev)),
1461                                 (char*)ev + sizeof(*ev) + ev->u.send_pdu.hdr_size,
1462                                 ev->u.send_pdu.data_size);
1463                 else
1464                         err = -EINVAL;
1465                 break;
1466         case ISCSI_UEVENT_GET_STATS:
1467                 err = iscsi_if_get_stats(transport, nlh);
1468                 break;
1469         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1470         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1471         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1472                 err = iscsi_if_transport_ep(transport, ev, nlh->nlmsg_type);
1473                 break;
1474         case ISCSI_UEVENT_TGT_DSCVR:
1475                 err = iscsi_tgt_dscvr(transport, ev);
1476                 break;
1477         case ISCSI_UEVENT_SET_HOST_PARAM:
1478                 err = iscsi_set_host_param(transport, ev);
1479                 break;
1480         default:
1481                 err = -ENOSYS;
1482                 break;
1483         }
1484
1485         module_put(transport->owner);
1486         return err;
1487 }
1488
1489 /*
1490  * Get message from skb.  Each message is processed by iscsi_if_recv_msg.
1491  * Malformed skbs with wrong lengths or invalid creds are not processed.
1492  */
1493 static void
1494 iscsi_if_rx(struct sk_buff *skb)
1495 {
1496         mutex_lock(&rx_queue_mutex);
1497         while (skb->len >= NLMSG_SPACE(0)) {
1498                 int err;
1499                 uint32_t rlen;
1500                 struct nlmsghdr *nlh;
1501                 struct iscsi_uevent *ev;
1502
1503                 nlh = nlmsg_hdr(skb);
1504                 if (nlh->nlmsg_len < sizeof(*nlh) ||
1505                     skb->len < nlh->nlmsg_len) {
1506                         break;
1507                 }
1508
1509                 ev = NLMSG_DATA(nlh);
1510                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1511                 if (rlen > skb->len)
1512                         rlen = skb->len;
1513
1514                 err = iscsi_if_recv_msg(skb, nlh);
1515                 if (err) {
1516                         ev->type = ISCSI_KEVENT_IF_ERROR;
1517                         ev->iferror = err;
1518                 }
1519                 do {
1520                         /*
1521                          * special case for GET_STATS:
1522                          * on success - sending reply and stats from
1523                          * inside of if_recv_msg(),
1524                          * on error - fall through.
1525                          */
1526                         if (ev->type == ISCSI_UEVENT_GET_STATS && !err)
1527                                 break;
1528                         err = iscsi_if_send_reply(
1529                                 NETLINK_CREDS(skb)->pid, nlh->nlmsg_seq,
1530                                 nlh->nlmsg_type, 0, 0, ev, sizeof(*ev));
1531                 } while (err < 0 && err != -ECONNREFUSED);
1532                 skb_pull(skb, rlen);
1533         }
1534         mutex_unlock(&rx_queue_mutex);
1535 }
1536
1537 #define ISCSI_CLASS_ATTR(_prefix,_name,_mode,_show,_store)              \
1538 struct device_attribute dev_attr_##_prefix##_##_name =  \
1539         __ATTR(_name,_mode,_show,_store)
1540
1541 /*
1542  * iSCSI connection attrs
1543  */
1544 #define iscsi_conn_attr_show(param)                                     \
1545 static ssize_t                                                          \
1546 show_conn_param_##param(struct device *dev,                             \
1547                         struct device_attribute *attr, char *buf)       \
1548 {                                                                       \
1549         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev->parent);   \
1550         struct iscsi_transport *t = conn->transport;                    \
1551         return t->get_conn_param(conn, param, buf);                     \
1552 }
1553
1554 #define iscsi_conn_attr(field, param)                                   \
1555         iscsi_conn_attr_show(param)                                     \
1556 static ISCSI_CLASS_ATTR(conn, field, S_IRUGO, show_conn_param_##param,  \
1557                         NULL);
1558
1559 iscsi_conn_attr(max_recv_dlength, ISCSI_PARAM_MAX_RECV_DLENGTH);
1560 iscsi_conn_attr(max_xmit_dlength, ISCSI_PARAM_MAX_XMIT_DLENGTH);
1561 iscsi_conn_attr(header_digest, ISCSI_PARAM_HDRDGST_EN);
1562 iscsi_conn_attr(data_digest, ISCSI_PARAM_DATADGST_EN);
1563 iscsi_conn_attr(ifmarker, ISCSI_PARAM_IFMARKER_EN);
1564 iscsi_conn_attr(ofmarker, ISCSI_PARAM_OFMARKER_EN);
1565 iscsi_conn_attr(persistent_port, ISCSI_PARAM_PERSISTENT_PORT);
1566 iscsi_conn_attr(port, ISCSI_PARAM_CONN_PORT);
1567 iscsi_conn_attr(exp_statsn, ISCSI_PARAM_EXP_STATSN);
1568 iscsi_conn_attr(persistent_address, ISCSI_PARAM_PERSISTENT_ADDRESS);
1569 iscsi_conn_attr(address, ISCSI_PARAM_CONN_ADDRESS);
1570 iscsi_conn_attr(ping_tmo, ISCSI_PARAM_PING_TMO);
1571 iscsi_conn_attr(recv_tmo, ISCSI_PARAM_RECV_TMO);
1572
1573 /*
1574  * iSCSI session attrs
1575  */
1576 #define iscsi_session_attr_show(param, perm)                            \
1577 static ssize_t                                                          \
1578 show_session_param_##param(struct device *dev,                          \
1579                            struct device_attribute *attr, char *buf)    \
1580 {                                                                       \
1581         struct iscsi_cls_session *session =                             \
1582                 iscsi_dev_to_session(dev->parent);                      \
1583         struct iscsi_transport *t = session->transport;                 \
1584                                                                         \
1585         if (perm && !capable(CAP_SYS_ADMIN))                            \
1586                 return -EACCES;                                         \
1587         return t->get_session_param(session, param, buf);               \
1588 }
1589
1590 #define iscsi_session_attr(field, param, perm)                          \
1591         iscsi_session_attr_show(param, perm)                            \
1592 static ISCSI_CLASS_ATTR(sess, field, S_IRUGO, show_session_param_##param, \
1593                         NULL);
1594
1595 iscsi_session_attr(targetname, ISCSI_PARAM_TARGET_NAME, 0);
1596 iscsi_session_attr(initial_r2t, ISCSI_PARAM_INITIAL_R2T_EN, 0);
1597 iscsi_session_attr(max_outstanding_r2t, ISCSI_PARAM_MAX_R2T, 0);
1598 iscsi_session_attr(immediate_data, ISCSI_PARAM_IMM_DATA_EN, 0);
1599 iscsi_session_attr(first_burst_len, ISCSI_PARAM_FIRST_BURST, 0);
1600 iscsi_session_attr(max_burst_len, ISCSI_PARAM_MAX_BURST, 0);
1601 iscsi_session_attr(data_pdu_in_order, ISCSI_PARAM_PDU_INORDER_EN, 0);
1602 iscsi_session_attr(data_seq_in_order, ISCSI_PARAM_DATASEQ_INORDER_EN, 0);
1603 iscsi_session_attr(erl, ISCSI_PARAM_ERL, 0);
1604 iscsi_session_attr(tpgt, ISCSI_PARAM_TPGT, 0);
1605 iscsi_session_attr(username, ISCSI_PARAM_USERNAME, 1);
1606 iscsi_session_attr(username_in, ISCSI_PARAM_USERNAME_IN, 1);
1607 iscsi_session_attr(password, ISCSI_PARAM_PASSWORD, 1);
1608 iscsi_session_attr(password_in, ISCSI_PARAM_PASSWORD_IN, 1);
1609 iscsi_session_attr(fast_abort, ISCSI_PARAM_FAST_ABORT, 0);
1610 iscsi_session_attr(abort_tmo, ISCSI_PARAM_ABORT_TMO, 0);
1611 iscsi_session_attr(lu_reset_tmo, ISCSI_PARAM_LU_RESET_TMO, 0);
1612 iscsi_session_attr(ifacename, ISCSI_PARAM_IFACE_NAME, 0);
1613 iscsi_session_attr(initiatorname, ISCSI_PARAM_INITIATOR_NAME, 0)
1614
1615 static ssize_t
1616 show_priv_session_state(struct device *dev, struct device_attribute *attr,
1617                         char *buf)
1618 {
1619         struct iscsi_cls_session *session = iscsi_dev_to_session(dev->parent);
1620         return sprintf(buf, "%s\n", iscsi_session_state_name(session->state));
1621 }
1622 static ISCSI_CLASS_ATTR(priv_sess, state, S_IRUGO, show_priv_session_state,
1623                         NULL);
1624
1625 #define iscsi_priv_session_attr_show(field, format)                     \
1626 static ssize_t                                                          \
1627 show_priv_session_##field(struct device *dev,                           \
1628                           struct device_attribute *attr, char *buf)     \
1629 {                                                                       \
1630         struct iscsi_cls_session *session =                             \
1631                         iscsi_dev_to_session(dev->parent);              \
1632         return sprintf(buf, format"\n", session->field);                \
1633 }
1634
1635 #define iscsi_priv_session_attr(field, format)                          \
1636         iscsi_priv_session_attr_show(field, format)                     \
1637 static ISCSI_CLASS_ATTR(priv_sess, field, S_IRUGO, show_priv_session_##field, \
1638                         NULL)
1639 iscsi_priv_session_attr(recovery_tmo, "%d");
1640
1641 /*
1642  * iSCSI host attrs
1643  */
1644 #define iscsi_host_attr_show(param)                                     \
1645 static ssize_t                                                          \
1646 show_host_param_##param(struct device *dev,                             \
1647                         struct device_attribute *attr, char *buf)       \
1648 {                                                                       \
1649         struct Scsi_Host *shost = transport_class_to_shost(dev);        \
1650         struct iscsi_internal *priv = to_iscsi_internal(shost->transportt); \
1651         return priv->iscsi_transport->get_host_param(shost, param, buf); \
1652 }
1653
1654 #define iscsi_host_attr(field, param)                                   \
1655         iscsi_host_attr_show(param)                                     \
1656 static ISCSI_CLASS_ATTR(host, field, S_IRUGO, show_host_param_##param,  \
1657                         NULL);
1658
1659 iscsi_host_attr(netdev, ISCSI_HOST_PARAM_NETDEV_NAME);
1660 iscsi_host_attr(hwaddress, ISCSI_HOST_PARAM_HWADDRESS);
1661 iscsi_host_attr(ipaddress, ISCSI_HOST_PARAM_IPADDRESS);
1662 iscsi_host_attr(initiatorname, ISCSI_HOST_PARAM_INITIATOR_NAME);
1663
1664 #define SETUP_PRIV_SESSION_RD_ATTR(field)                               \
1665 do {                                                                    \
1666         priv->session_attrs[count] = &dev_attr_priv_sess_##field; \
1667         count++;                                                        \
1668 } while (0)
1669
1670
1671 #define SETUP_SESSION_RD_ATTR(field, param_flag)                        \
1672 do {                                                                    \
1673         if (tt->param_mask & param_flag) {                              \
1674                 priv->session_attrs[count] = &dev_attr_sess_##field; \
1675                 count++;                                                \
1676         }                                                               \
1677 } while (0)
1678
1679 #define SETUP_CONN_RD_ATTR(field, param_flag)                           \
1680 do {                                                                    \
1681         if (tt->param_mask & param_flag) {                              \
1682                 priv->conn_attrs[count] = &dev_attr_conn_##field; \
1683                 count++;                                                \
1684         }                                                               \
1685 } while (0)
1686
1687 #define SETUP_HOST_RD_ATTR(field, param_flag)                           \
1688 do {                                                                    \
1689         if (tt->host_param_mask & param_flag) {                         \
1690                 priv->host_attrs[count] = &dev_attr_host_##field; \
1691                 count++;                                                \
1692         }                                                               \
1693 } while (0)
1694
1695 static int iscsi_session_match(struct attribute_container *cont,
1696                            struct device *dev)
1697 {
1698         struct iscsi_cls_session *session;
1699         struct Scsi_Host *shost;
1700         struct iscsi_internal *priv;
1701
1702         if (!iscsi_is_session_dev(dev))
1703                 return 0;
1704
1705         session = iscsi_dev_to_session(dev);
1706         shost = iscsi_session_to_shost(session);
1707         if (!shost->transportt)
1708                 return 0;
1709
1710         priv = to_iscsi_internal(shost->transportt);
1711         if (priv->session_cont.ac.class != &iscsi_session_class.class)
1712                 return 0;
1713
1714         return &priv->session_cont.ac == cont;
1715 }
1716
1717 static int iscsi_conn_match(struct attribute_container *cont,
1718                            struct device *dev)
1719 {
1720         struct iscsi_cls_session *session;
1721         struct iscsi_cls_conn *conn;
1722         struct Scsi_Host *shost;
1723         struct iscsi_internal *priv;
1724
1725         if (!iscsi_is_conn_dev(dev))
1726                 return 0;
1727
1728         conn = iscsi_dev_to_conn(dev);
1729         session = iscsi_dev_to_session(conn->dev.parent);
1730         shost = iscsi_session_to_shost(session);
1731
1732         if (!shost->transportt)
1733                 return 0;
1734
1735         priv = to_iscsi_internal(shost->transportt);
1736         if (priv->conn_cont.ac.class != &iscsi_connection_class.class)
1737                 return 0;
1738
1739         return &priv->conn_cont.ac == cont;
1740 }
1741
1742 static int iscsi_host_match(struct attribute_container *cont,
1743                             struct device *dev)
1744 {
1745         struct Scsi_Host *shost;
1746         struct iscsi_internal *priv;
1747
1748         if (!scsi_is_host_device(dev))
1749                 return 0;
1750
1751         shost = dev_to_shost(dev);
1752         if (!shost->transportt  ||
1753             shost->transportt->host_attrs.ac.class != &iscsi_host_class.class)
1754                 return 0;
1755
1756         priv = to_iscsi_internal(shost->transportt);
1757         return &priv->t.host_attrs.ac == cont;
1758 }
1759
1760 struct scsi_transport_template *
1761 iscsi_register_transport(struct iscsi_transport *tt)
1762 {
1763         struct iscsi_internal *priv;
1764         unsigned long flags;
1765         int count = 0, err;
1766
1767         BUG_ON(!tt);
1768
1769         priv = iscsi_if_transport_lookup(tt);
1770         if (priv)
1771                 return NULL;
1772
1773         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1774         if (!priv)
1775                 return NULL;
1776         INIT_LIST_HEAD(&priv->list);
1777         priv->daemon_pid = -1;
1778         priv->iscsi_transport = tt;
1779         priv->t.user_scan = iscsi_user_scan;
1780         priv->t.create_work_queue = 1;
1781
1782         priv->dev.class = &iscsi_transport_class;
1783         dev_set_name(&priv->dev, "%s", tt->name);
1784         err = device_register(&priv->dev);
1785         if (err)
1786                 goto free_priv;
1787
1788         err = sysfs_create_group(&priv->dev.kobj, &iscsi_transport_group);
1789         if (err)
1790                 goto unregister_dev;
1791
1792         /* host parameters */
1793         priv->t.host_attrs.ac.attrs = &priv->host_attrs[0];
1794         priv->t.host_attrs.ac.class = &iscsi_host_class.class;
1795         priv->t.host_attrs.ac.match = iscsi_host_match;
1796         priv->t.host_size = sizeof(struct iscsi_cls_host);
1797         transport_container_register(&priv->t.host_attrs);
1798
1799         SETUP_HOST_RD_ATTR(netdev, ISCSI_HOST_NETDEV_NAME);
1800         SETUP_HOST_RD_ATTR(ipaddress, ISCSI_HOST_IPADDRESS);
1801         SETUP_HOST_RD_ATTR(hwaddress, ISCSI_HOST_HWADDRESS);
1802         SETUP_HOST_RD_ATTR(initiatorname, ISCSI_HOST_INITIATOR_NAME);
1803         BUG_ON(count > ISCSI_HOST_ATTRS);
1804         priv->host_attrs[count] = NULL;
1805         count = 0;
1806
1807         /* connection parameters */
1808         priv->conn_cont.ac.attrs = &priv->conn_attrs[0];
1809         priv->conn_cont.ac.class = &iscsi_connection_class.class;
1810         priv->conn_cont.ac.match = iscsi_conn_match;
1811         transport_container_register(&priv->conn_cont);
1812
1813         SETUP_CONN_RD_ATTR(max_recv_dlength, ISCSI_MAX_RECV_DLENGTH);
1814         SETUP_CONN_RD_ATTR(max_xmit_dlength, ISCSI_MAX_XMIT_DLENGTH);
1815         SETUP_CONN_RD_ATTR(header_digest, ISCSI_HDRDGST_EN);
1816         SETUP_CONN_RD_ATTR(data_digest, ISCSI_DATADGST_EN);
1817         SETUP_CONN_RD_ATTR(ifmarker, ISCSI_IFMARKER_EN);
1818         SETUP_CONN_RD_ATTR(ofmarker, ISCSI_OFMARKER_EN);
1819         SETUP_CONN_RD_ATTR(address, ISCSI_CONN_ADDRESS);
1820         SETUP_CONN_RD_ATTR(port, ISCSI_CONN_PORT);
1821         SETUP_CONN_RD_ATTR(exp_statsn, ISCSI_EXP_STATSN);
1822         SETUP_CONN_RD_ATTR(persistent_address, ISCSI_PERSISTENT_ADDRESS);
1823         SETUP_CONN_RD_ATTR(persistent_port, ISCSI_PERSISTENT_PORT);
1824         SETUP_CONN_RD_ATTR(ping_tmo, ISCSI_PING_TMO);
1825         SETUP_CONN_RD_ATTR(recv_tmo, ISCSI_RECV_TMO);
1826
1827         BUG_ON(count > ISCSI_CONN_ATTRS);
1828         priv->conn_attrs[count] = NULL;
1829         count = 0;
1830
1831         /* session parameters */
1832         priv->session_cont.ac.attrs = &priv->session_attrs[0];
1833         priv->session_cont.ac.class = &iscsi_session_class.class;
1834         priv->session_cont.ac.match = iscsi_session_match;
1835         transport_container_register(&priv->session_cont);
1836
1837         SETUP_SESSION_RD_ATTR(initial_r2t, ISCSI_INITIAL_R2T_EN);
1838         SETUP_SESSION_RD_ATTR(max_outstanding_r2t, ISCSI_MAX_R2T);
1839         SETUP_SESSION_RD_ATTR(immediate_data, ISCSI_IMM_DATA_EN);
1840         SETUP_SESSION_RD_ATTR(first_burst_len, ISCSI_FIRST_BURST);
1841         SETUP_SESSION_RD_ATTR(max_burst_len, ISCSI_MAX_BURST);
1842         SETUP_SESSION_RD_ATTR(data_pdu_in_order, ISCSI_PDU_INORDER_EN);
1843         SETUP_SESSION_RD_ATTR(data_seq_in_order, ISCSI_DATASEQ_INORDER_EN);
1844         SETUP_SESSION_RD_ATTR(erl, ISCSI_ERL);
1845         SETUP_SESSION_RD_ATTR(targetname, ISCSI_TARGET_NAME);
1846         SETUP_SESSION_RD_ATTR(tpgt, ISCSI_TPGT);
1847         SETUP_SESSION_RD_ATTR(password, ISCSI_USERNAME);
1848         SETUP_SESSION_RD_ATTR(password_in, ISCSI_USERNAME_IN);
1849         SETUP_SESSION_RD_ATTR(username, ISCSI_PASSWORD);
1850         SETUP_SESSION_RD_ATTR(username_in, ISCSI_PASSWORD_IN);
1851         SETUP_SESSION_RD_ATTR(fast_abort, ISCSI_FAST_ABORT);
1852         SETUP_SESSION_RD_ATTR(abort_tmo, ISCSI_ABORT_TMO);
1853         SETUP_SESSION_RD_ATTR(lu_reset_tmo,ISCSI_LU_RESET_TMO);
1854         SETUP_SESSION_RD_ATTR(ifacename, ISCSI_IFACE_NAME);
1855         SETUP_SESSION_RD_ATTR(initiatorname, ISCSI_INITIATOR_NAME);
1856         SETUP_PRIV_SESSION_RD_ATTR(recovery_tmo);
1857         SETUP_PRIV_SESSION_RD_ATTR(state);
1858
1859         BUG_ON(count > ISCSI_SESSION_ATTRS);
1860         priv->session_attrs[count] = NULL;
1861
1862         spin_lock_irqsave(&iscsi_transport_lock, flags);
1863         list_add(&priv->list, &iscsi_transports);
1864         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1865
1866         printk(KERN_NOTICE "iscsi: registered transport (%s)\n", tt->name);
1867         return &priv->t;
1868
1869 unregister_dev:
1870         device_unregister(&priv->dev);
1871         return NULL;
1872 free_priv:
1873         kfree(priv);
1874         return NULL;
1875 }
1876 EXPORT_SYMBOL_GPL(iscsi_register_transport);
1877
1878 int iscsi_unregister_transport(struct iscsi_transport *tt)
1879 {
1880         struct iscsi_internal *priv;
1881         unsigned long flags;
1882
1883         BUG_ON(!tt);
1884
1885         mutex_lock(&rx_queue_mutex);
1886
1887         priv = iscsi_if_transport_lookup(tt);
1888         BUG_ON (!priv);
1889
1890         spin_lock_irqsave(&iscsi_transport_lock, flags);
1891         list_del(&priv->list);
1892         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1893
1894         transport_container_unregister(&priv->conn_cont);
1895         transport_container_unregister(&priv->session_cont);
1896         transport_container_unregister(&priv->t.host_attrs);
1897
1898         sysfs_remove_group(&priv->dev.kobj, &iscsi_transport_group);
1899         device_unregister(&priv->dev);
1900         mutex_unlock(&rx_queue_mutex);
1901
1902         return 0;
1903 }
1904 EXPORT_SYMBOL_GPL(iscsi_unregister_transport);
1905
1906 static __init int iscsi_transport_init(void)
1907 {
1908         int err;
1909
1910         printk(KERN_INFO "Loading iSCSI transport class v%s.\n",
1911                 ISCSI_TRANSPORT_VERSION);
1912
1913         atomic_set(&iscsi_session_nr, 0);
1914
1915         err = class_register(&iscsi_transport_class);
1916         if (err)
1917                 return err;
1918
1919         err = class_register(&iscsi_endpoint_class);
1920         if (err)
1921                 goto unregister_transport_class;
1922
1923         err = transport_class_register(&iscsi_host_class);
1924         if (err)
1925                 goto unregister_endpoint_class;
1926
1927         err = transport_class_register(&iscsi_connection_class);
1928         if (err)
1929                 goto unregister_host_class;
1930
1931         err = transport_class_register(&iscsi_session_class);
1932         if (err)
1933                 goto unregister_conn_class;
1934
1935         nls = netlink_kernel_create(&init_net, NETLINK_ISCSI, 1, iscsi_if_rx,
1936                                     NULL, THIS_MODULE);
1937         if (!nls) {
1938                 err = -ENOBUFS;
1939                 goto unregister_session_class;
1940         }
1941
1942         iscsi_eh_timer_workq = create_singlethread_workqueue("iscsi_eh");
1943         if (!iscsi_eh_timer_workq)
1944                 goto release_nls;
1945
1946         return 0;
1947
1948 release_nls:
1949         netlink_kernel_release(nls);
1950 unregister_session_class:
1951         transport_class_unregister(&iscsi_session_class);
1952 unregister_conn_class:
1953         transport_class_unregister(&iscsi_connection_class);
1954 unregister_host_class:
1955         transport_class_unregister(&iscsi_host_class);
1956 unregister_endpoint_class:
1957         class_unregister(&iscsi_endpoint_class);
1958 unregister_transport_class:
1959         class_unregister(&iscsi_transport_class);
1960         return err;
1961 }
1962
1963 static void __exit iscsi_transport_exit(void)
1964 {
1965         destroy_workqueue(iscsi_eh_timer_workq);
1966         netlink_kernel_release(nls);
1967         transport_class_unregister(&iscsi_connection_class);
1968         transport_class_unregister(&iscsi_session_class);
1969         transport_class_unregister(&iscsi_host_class);
1970         class_unregister(&iscsi_endpoint_class);
1971         class_unregister(&iscsi_transport_class);
1972 }
1973
1974 module_init(iscsi_transport_init);
1975 module_exit(iscsi_transport_exit);
1976
1977 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
1978               "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
1979               "Alex Aizman <itn780@yahoo.com>");
1980 MODULE_DESCRIPTION("iSCSI Transport Interface");
1981 MODULE_LICENSE("GPL");
1982 MODULE_VERSION(ISCSI_TRANSPORT_VERSION);