d4b96623aa59fa5c886c61fdfcd97010dab8231f
[linux-2.6.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 <linux/slab.h>
26 #include <net/tcp.h>
27 #include <scsi/scsi.h>
28 #include <scsi/scsi_host.h>
29 #include <scsi/scsi_device.h>
30 #include <scsi/scsi_transport.h>
31 #include <scsi/scsi_transport_iscsi.h>
32 #include <scsi/iscsi_if.h>
33
34 #define ISCSI_SESSION_ATTRS 23
35 #define ISCSI_CONN_ATTRS 13
36 #define ISCSI_HOST_ATTRS 4
37
38 #define ISCSI_TRANSPORT_VERSION "2.0-870"
39
40 static int dbg_session;
41 module_param_named(debug_session, dbg_session, int,
42                    S_IRUGO | S_IWUSR);
43 MODULE_PARM_DESC(debug_session,
44                  "Turn on debugging for sessions in scsi_transport_iscsi "
45                  "module. Set to 1 to turn on, and zero to turn off. Default "
46                  "is off.");
47
48 static int dbg_conn;
49 module_param_named(debug_conn, dbg_conn, int,
50                    S_IRUGO | S_IWUSR);
51 MODULE_PARM_DESC(debug_conn,
52                  "Turn on debugging for connections in scsi_transport_iscsi "
53                  "module. Set to 1 to turn on, and zero to turn off. Default "
54                  "is off.");
55
56 #define ISCSI_DBG_TRANS_SESSION(_session, dbg_fmt, arg...)              \
57         do {                                                            \
58                 if (dbg_session)                                        \
59                         iscsi_cls_session_printk(KERN_INFO, _session,   \
60                                                  "%s: " dbg_fmt,        \
61                                                  __func__, ##arg);      \
62         } while (0);
63
64 #define ISCSI_DBG_TRANS_CONN(_conn, dbg_fmt, arg...)                    \
65         do {                                                            \
66                 if (dbg_conn)                                           \
67                         iscsi_cls_conn_printk(KERN_INFO, _conn,         \
68                                               "%s: " dbg_fmt,           \
69                                               __func__, ##arg); \
70         } while (0);
71
72 struct iscsi_internal {
73         struct scsi_transport_template t;
74         struct iscsi_transport *iscsi_transport;
75         struct list_head list;
76         struct device dev;
77
78         struct device_attribute *host_attrs[ISCSI_HOST_ATTRS + 1];
79         struct transport_container conn_cont;
80         struct device_attribute *conn_attrs[ISCSI_CONN_ATTRS + 1];
81         struct transport_container session_cont;
82         struct device_attribute *session_attrs[ISCSI_SESSION_ATTRS + 1];
83 };
84
85 static atomic_t iscsi_session_nr; /* sysfs session id for next new session */
86 static struct workqueue_struct *iscsi_eh_timer_workq;
87
88 /*
89  * list of registered transports and lock that must
90  * be held while accessing list. The iscsi_transport_lock must
91  * be acquired after the rx_queue_mutex.
92  */
93 static LIST_HEAD(iscsi_transports);
94 static DEFINE_SPINLOCK(iscsi_transport_lock);
95
96 #define to_iscsi_internal(tmpl) \
97         container_of(tmpl, struct iscsi_internal, t)
98
99 #define dev_to_iscsi_internal(_dev) \
100         container_of(_dev, struct iscsi_internal, dev)
101
102 static void iscsi_transport_release(struct device *dev)
103 {
104         struct iscsi_internal *priv = dev_to_iscsi_internal(dev);
105         kfree(priv);
106 }
107
108 /*
109  * iscsi_transport_class represents the iscsi_transports that are
110  * registered.
111  */
112 static struct class iscsi_transport_class = {
113         .name = "iscsi_transport",
114         .dev_release = iscsi_transport_release,
115 };
116
117 static ssize_t
118 show_transport_handle(struct device *dev, struct device_attribute *attr,
119                       char *buf)
120 {
121         struct iscsi_internal *priv = dev_to_iscsi_internal(dev);
122         return sprintf(buf, "%llu\n", (unsigned long long)iscsi_handle(priv->iscsi_transport));
123 }
124 static DEVICE_ATTR(handle, S_IRUGO, show_transport_handle, NULL);
125
126 #define show_transport_attr(name, format)                               \
127 static ssize_t                                                          \
128 show_transport_##name(struct device *dev,                               \
129                       struct device_attribute *attr,char *buf)          \
130 {                                                                       \
131         struct iscsi_internal *priv = dev_to_iscsi_internal(dev);       \
132         return sprintf(buf, format"\n", priv->iscsi_transport->name);   \
133 }                                                                       \
134 static DEVICE_ATTR(name, S_IRUGO, show_transport_##name, NULL);
135
136 show_transport_attr(caps, "0x%x");
137
138 static struct attribute *iscsi_transport_attrs[] = {
139         &dev_attr_handle.attr,
140         &dev_attr_caps.attr,
141         NULL,
142 };
143
144 static struct attribute_group iscsi_transport_group = {
145         .attrs = iscsi_transport_attrs,
146 };
147
148 /*
149  * iSCSI endpoint attrs
150  */
151 #define iscsi_dev_to_endpoint(_dev) \
152         container_of(_dev, struct iscsi_endpoint, dev)
153
154 #define ISCSI_ATTR(_prefix,_name,_mode,_show,_store)    \
155 struct device_attribute dev_attr_##_prefix##_##_name =  \
156         __ATTR(_name,_mode,_show,_store)
157
158 static void iscsi_endpoint_release(struct device *dev)
159 {
160         struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
161         kfree(ep);
162 }
163
164 static struct class iscsi_endpoint_class = {
165         .name = "iscsi_endpoint",
166         .dev_release = iscsi_endpoint_release,
167 };
168
169 static ssize_t
170 show_ep_handle(struct device *dev, struct device_attribute *attr, char *buf)
171 {
172         struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
173         return sprintf(buf, "%llu\n", (unsigned long long) ep->id);
174 }
175 static ISCSI_ATTR(ep, handle, S_IRUGO, show_ep_handle, NULL);
176
177 static struct attribute *iscsi_endpoint_attrs[] = {
178         &dev_attr_ep_handle.attr,
179         NULL,
180 };
181
182 static struct attribute_group iscsi_endpoint_group = {
183         .attrs = iscsi_endpoint_attrs,
184 };
185
186 #define ISCSI_MAX_EPID -1
187
188 static int iscsi_match_epid(struct device *dev, void *data)
189 {
190         struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
191         uint64_t *epid = (uint64_t *) data;
192
193         return *epid == ep->id;
194 }
195
196 struct iscsi_endpoint *
197 iscsi_create_endpoint(int dd_size)
198 {
199         struct device *dev;
200         struct iscsi_endpoint *ep;
201         uint64_t id;
202         int err;
203
204         for (id = 1; id < ISCSI_MAX_EPID; id++) {
205                 dev = class_find_device(&iscsi_endpoint_class, NULL, &id,
206                                         iscsi_match_epid);
207                 if (!dev)
208                         break;
209         }
210         if (id == ISCSI_MAX_EPID) {
211                 printk(KERN_ERR "Too many connections. Max supported %u\n",
212                        ISCSI_MAX_EPID - 1);
213                 return NULL;
214         }
215
216         ep = kzalloc(sizeof(*ep) + dd_size, GFP_KERNEL);
217         if (!ep)
218                 return NULL;
219
220         ep->id = id;
221         ep->dev.class = &iscsi_endpoint_class;
222         dev_set_name(&ep->dev, "ep-%llu", (unsigned long long) id);
223         err = device_register(&ep->dev);
224         if (err)
225                 goto free_ep;
226
227         err = sysfs_create_group(&ep->dev.kobj, &iscsi_endpoint_group);
228         if (err)
229                 goto unregister_dev;
230
231         if (dd_size)
232                 ep->dd_data = &ep[1];
233         return ep;
234
235 unregister_dev:
236         device_unregister(&ep->dev);
237         return NULL;
238
239 free_ep:
240         kfree(ep);
241         return NULL;
242 }
243 EXPORT_SYMBOL_GPL(iscsi_create_endpoint);
244
245 void iscsi_destroy_endpoint(struct iscsi_endpoint *ep)
246 {
247         sysfs_remove_group(&ep->dev.kobj, &iscsi_endpoint_group);
248         device_unregister(&ep->dev);
249 }
250 EXPORT_SYMBOL_GPL(iscsi_destroy_endpoint);
251
252 struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle)
253 {
254         struct iscsi_endpoint *ep;
255         struct device *dev;
256
257         dev = class_find_device(&iscsi_endpoint_class, NULL, &handle,
258                                 iscsi_match_epid);
259         if (!dev)
260                 return NULL;
261
262         ep = iscsi_dev_to_endpoint(dev);
263         /*
264          * we can drop this now because the interface will prevent
265          * removals and lookups from racing.
266          */
267         put_device(dev);
268         return ep;
269 }
270 EXPORT_SYMBOL_GPL(iscsi_lookup_endpoint);
271
272 static int iscsi_setup_host(struct transport_container *tc, struct device *dev,
273                             struct device *cdev)
274 {
275         struct Scsi_Host *shost = dev_to_shost(dev);
276         struct iscsi_cls_host *ihost = shost->shost_data;
277
278         memset(ihost, 0, sizeof(*ihost));
279         atomic_set(&ihost->nr_scans, 0);
280         mutex_init(&ihost->mutex);
281         return 0;
282 }
283
284 static DECLARE_TRANSPORT_CLASS(iscsi_host_class,
285                                "iscsi_host",
286                                iscsi_setup_host,
287                                NULL,
288                                NULL);
289
290 static DECLARE_TRANSPORT_CLASS(iscsi_session_class,
291                                "iscsi_session",
292                                NULL,
293                                NULL,
294                                NULL);
295
296 static DECLARE_TRANSPORT_CLASS(iscsi_connection_class,
297                                "iscsi_connection",
298                                NULL,
299                                NULL,
300                                NULL);
301
302 static struct sock *nls;
303 static DEFINE_MUTEX(rx_queue_mutex);
304
305 static LIST_HEAD(sesslist);
306 static DEFINE_SPINLOCK(sesslock);
307 static LIST_HEAD(connlist);
308 static DEFINE_SPINLOCK(connlock);
309
310 static uint32_t iscsi_conn_get_sid(struct iscsi_cls_conn *conn)
311 {
312         struct iscsi_cls_session *sess = iscsi_dev_to_session(conn->dev.parent);
313         return sess->sid;
314 }
315
316 /*
317  * Returns the matching session to a given sid
318  */
319 static struct iscsi_cls_session *iscsi_session_lookup(uint32_t sid)
320 {
321         unsigned long flags;
322         struct iscsi_cls_session *sess;
323
324         spin_lock_irqsave(&sesslock, flags);
325         list_for_each_entry(sess, &sesslist, sess_list) {
326                 if (sess->sid == sid) {
327                         spin_unlock_irqrestore(&sesslock, flags);
328                         return sess;
329                 }
330         }
331         spin_unlock_irqrestore(&sesslock, flags);
332         return NULL;
333 }
334
335 /*
336  * Returns the matching connection to a given sid / cid tuple
337  */
338 static struct iscsi_cls_conn *iscsi_conn_lookup(uint32_t sid, uint32_t cid)
339 {
340         unsigned long flags;
341         struct iscsi_cls_conn *conn;
342
343         spin_lock_irqsave(&connlock, flags);
344         list_for_each_entry(conn, &connlist, conn_list) {
345                 if ((conn->cid == cid) && (iscsi_conn_get_sid(conn) == sid)) {
346                         spin_unlock_irqrestore(&connlock, flags);
347                         return conn;
348                 }
349         }
350         spin_unlock_irqrestore(&connlock, flags);
351         return NULL;
352 }
353
354 /*
355  * The following functions can be used by LLDs that allocate
356  * their own scsi_hosts or by software iscsi LLDs
357  */
358 static struct {
359         int value;
360         char *name;
361 } iscsi_session_state_names[] = {
362         { ISCSI_SESSION_LOGGED_IN,      "LOGGED_IN" },
363         { ISCSI_SESSION_FAILED,         "FAILED" },
364         { ISCSI_SESSION_FREE,           "FREE" },
365 };
366
367 static const char *iscsi_session_state_name(int state)
368 {
369         int i;
370         char *name = NULL;
371
372         for (i = 0; i < ARRAY_SIZE(iscsi_session_state_names); i++) {
373                 if (iscsi_session_state_names[i].value == state) {
374                         name = iscsi_session_state_names[i].name;
375                         break;
376                 }
377         }
378         return name;
379 }
380
381 int iscsi_session_chkready(struct iscsi_cls_session *session)
382 {
383         unsigned long flags;
384         int err;
385
386         spin_lock_irqsave(&session->lock, flags);
387         switch (session->state) {
388         case ISCSI_SESSION_LOGGED_IN:
389                 err = 0;
390                 break;
391         case ISCSI_SESSION_FAILED:
392                 err = DID_IMM_RETRY << 16;
393                 break;
394         case ISCSI_SESSION_FREE:
395                 err = DID_TRANSPORT_FAILFAST << 16;
396                 break;
397         default:
398                 err = DID_NO_CONNECT << 16;
399                 break;
400         }
401         spin_unlock_irqrestore(&session->lock, flags);
402         return err;
403 }
404 EXPORT_SYMBOL_GPL(iscsi_session_chkready);
405
406 static void iscsi_session_release(struct device *dev)
407 {
408         struct iscsi_cls_session *session = iscsi_dev_to_session(dev);
409         struct Scsi_Host *shost;
410
411         shost = iscsi_session_to_shost(session);
412         scsi_host_put(shost);
413         ISCSI_DBG_TRANS_SESSION(session, "Completing session release\n");
414         kfree(session);
415 }
416
417 static int iscsi_is_session_dev(const struct device *dev)
418 {
419         return dev->release == iscsi_session_release;
420 }
421
422 static int iscsi_iter_session_fn(struct device *dev, void *data)
423 {
424         void (* fn) (struct iscsi_cls_session *) = data;
425
426         if (!iscsi_is_session_dev(dev))
427                 return 0;
428         fn(iscsi_dev_to_session(dev));
429         return 0;
430 }
431
432 void iscsi_host_for_each_session(struct Scsi_Host *shost,
433                                  void (*fn)(struct iscsi_cls_session *))
434 {
435         device_for_each_child(&shost->shost_gendev, fn,
436                               iscsi_iter_session_fn);
437 }
438 EXPORT_SYMBOL_GPL(iscsi_host_for_each_session);
439
440 /**
441  * iscsi_scan_finished - helper to report when running scans are done
442  * @shost: scsi host
443  * @time: scan run time
444  *
445  * This function can be used by drives like qla4xxx to report to the scsi
446  * layer when the scans it kicked off at module load time are done.
447  */
448 int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time)
449 {
450         struct iscsi_cls_host *ihost = shost->shost_data;
451         /*
452          * qla4xxx will have kicked off some session unblocks before calling
453          * scsi_scan_host, so just wait for them to complete.
454          */
455         return !atomic_read(&ihost->nr_scans);
456 }
457 EXPORT_SYMBOL_GPL(iscsi_scan_finished);
458
459 struct iscsi_scan_data {
460         unsigned int channel;
461         unsigned int id;
462         unsigned int lun;
463 };
464
465 static int iscsi_user_scan_session(struct device *dev, void *data)
466 {
467         struct iscsi_scan_data *scan_data = data;
468         struct iscsi_cls_session *session;
469         struct Scsi_Host *shost;
470         struct iscsi_cls_host *ihost;
471         unsigned long flags;
472         unsigned int id;
473
474         if (!iscsi_is_session_dev(dev))
475                 return 0;
476
477         session = iscsi_dev_to_session(dev);
478
479         ISCSI_DBG_TRANS_SESSION(session, "Scanning session\n");
480
481         shost = iscsi_session_to_shost(session);
482         ihost = shost->shost_data;
483
484         mutex_lock(&ihost->mutex);
485         spin_lock_irqsave(&session->lock, flags);
486         if (session->state != ISCSI_SESSION_LOGGED_IN) {
487                 spin_unlock_irqrestore(&session->lock, flags);
488                 goto user_scan_exit;
489         }
490         id = session->target_id;
491         spin_unlock_irqrestore(&session->lock, flags);
492
493         if (id != ISCSI_MAX_TARGET) {
494                 if ((scan_data->channel == SCAN_WILD_CARD ||
495                      scan_data->channel == 0) &&
496                     (scan_data->id == SCAN_WILD_CARD ||
497                      scan_data->id == id))
498                         scsi_scan_target(&session->dev, 0, id,
499                                          scan_data->lun, 1);
500         }
501
502 user_scan_exit:
503         mutex_unlock(&ihost->mutex);
504         ISCSI_DBG_TRANS_SESSION(session, "Completed session scan\n");
505         return 0;
506 }
507
508 static int iscsi_user_scan(struct Scsi_Host *shost, uint channel,
509                            uint id, uint lun)
510 {
511         struct iscsi_scan_data scan_data;
512
513         scan_data.channel = channel;
514         scan_data.id = id;
515         scan_data.lun = lun;
516
517         return device_for_each_child(&shost->shost_gendev, &scan_data,
518                                      iscsi_user_scan_session);
519 }
520
521 static void iscsi_scan_session(struct work_struct *work)
522 {
523         struct iscsi_cls_session *session =
524                         container_of(work, struct iscsi_cls_session, scan_work);
525         struct Scsi_Host *shost = iscsi_session_to_shost(session);
526         struct iscsi_cls_host *ihost = shost->shost_data;
527         struct iscsi_scan_data scan_data;
528
529         scan_data.channel = 0;
530         scan_data.id = SCAN_WILD_CARD;
531         scan_data.lun = SCAN_WILD_CARD;
532
533         iscsi_user_scan_session(&session->dev, &scan_data);
534         atomic_dec(&ihost->nr_scans);
535 }
536
537 static void session_recovery_timedout(struct work_struct *work)
538 {
539         struct iscsi_cls_session *session =
540                 container_of(work, struct iscsi_cls_session,
541                              recovery_work.work);
542         unsigned long flags;
543
544         iscsi_cls_session_printk(KERN_INFO, session,
545                                  "session recovery timed out after %d secs\n",
546                                  session->recovery_tmo);
547
548         spin_lock_irqsave(&session->lock, flags);
549         switch (session->state) {
550         case ISCSI_SESSION_FAILED:
551                 session->state = ISCSI_SESSION_FREE;
552                 break;
553         case ISCSI_SESSION_LOGGED_IN:
554         case ISCSI_SESSION_FREE:
555                 /* we raced with the unblock's flush */
556                 spin_unlock_irqrestore(&session->lock, flags);
557                 return;
558         }
559         spin_unlock_irqrestore(&session->lock, flags);
560
561         if (session->transport->session_recovery_timedout)
562                 session->transport->session_recovery_timedout(session);
563
564         ISCSI_DBG_TRANS_SESSION(session, "Unblocking SCSI target\n");
565         scsi_target_unblock(&session->dev);
566         ISCSI_DBG_TRANS_SESSION(session, "Completed unblocking SCSI target\n");
567 }
568
569 static void __iscsi_unblock_session(struct work_struct *work)
570 {
571         struct iscsi_cls_session *session =
572                         container_of(work, struct iscsi_cls_session,
573                                      unblock_work);
574         struct Scsi_Host *shost = iscsi_session_to_shost(session);
575         struct iscsi_cls_host *ihost = shost->shost_data;
576         unsigned long flags;
577
578         ISCSI_DBG_TRANS_SESSION(session, "Unblocking session\n");
579         /*
580          * The recovery and unblock work get run from the same workqueue,
581          * so try to cancel it if it was going to run after this unblock.
582          */
583         cancel_delayed_work(&session->recovery_work);
584         spin_lock_irqsave(&session->lock, flags);
585         session->state = ISCSI_SESSION_LOGGED_IN;
586         spin_unlock_irqrestore(&session->lock, flags);
587         /* start IO */
588         scsi_target_unblock(&session->dev);
589         /*
590          * Only do kernel scanning if the driver is properly hooked into
591          * the async scanning code (drivers like iscsi_tcp do login and
592          * scanning from userspace).
593          */
594         if (shost->hostt->scan_finished) {
595                 if (scsi_queue_work(shost, &session->scan_work))
596                         atomic_inc(&ihost->nr_scans);
597         }
598         ISCSI_DBG_TRANS_SESSION(session, "Completed unblocking session\n");
599 }
600
601 /**
602  * iscsi_unblock_session - set a session as logged in and start IO.
603  * @session: iscsi session
604  *
605  * Mark a session as ready to accept IO.
606  */
607 void iscsi_unblock_session(struct iscsi_cls_session *session)
608 {
609         queue_work(iscsi_eh_timer_workq, &session->unblock_work);
610         /*
611          * make sure all the events have completed before tell the driver
612          * it is safe
613          */
614         flush_workqueue(iscsi_eh_timer_workq);
615 }
616 EXPORT_SYMBOL_GPL(iscsi_unblock_session);
617
618 static void __iscsi_block_session(struct work_struct *work)
619 {
620         struct iscsi_cls_session *session =
621                         container_of(work, struct iscsi_cls_session,
622                                      block_work);
623         unsigned long flags;
624
625         ISCSI_DBG_TRANS_SESSION(session, "Blocking session\n");
626         spin_lock_irqsave(&session->lock, flags);
627         session->state = ISCSI_SESSION_FAILED;
628         spin_unlock_irqrestore(&session->lock, flags);
629         scsi_target_block(&session->dev);
630         ISCSI_DBG_TRANS_SESSION(session, "Completed SCSI target blocking\n");
631         if (session->recovery_tmo >= 0)
632                 queue_delayed_work(iscsi_eh_timer_workq,
633                                    &session->recovery_work,
634                                    session->recovery_tmo * HZ);
635 }
636
637 void iscsi_block_session(struct iscsi_cls_session *session)
638 {
639         queue_work(iscsi_eh_timer_workq, &session->block_work);
640 }
641 EXPORT_SYMBOL_GPL(iscsi_block_session);
642
643 static void __iscsi_unbind_session(struct work_struct *work)
644 {
645         struct iscsi_cls_session *session =
646                         container_of(work, struct iscsi_cls_session,
647                                      unbind_work);
648         struct Scsi_Host *shost = iscsi_session_to_shost(session);
649         struct iscsi_cls_host *ihost = shost->shost_data;
650         unsigned long flags;
651
652         ISCSI_DBG_TRANS_SESSION(session, "Unbinding session\n");
653
654         /* Prevent new scans and make sure scanning is not in progress */
655         mutex_lock(&ihost->mutex);
656         spin_lock_irqsave(&session->lock, flags);
657         if (session->target_id == ISCSI_MAX_TARGET) {
658                 spin_unlock_irqrestore(&session->lock, flags);
659                 mutex_unlock(&ihost->mutex);
660                 return;
661         }
662         session->target_id = ISCSI_MAX_TARGET;
663         spin_unlock_irqrestore(&session->lock, flags);
664         mutex_unlock(&ihost->mutex);
665
666         scsi_remove_target(&session->dev);
667         iscsi_session_event(session, ISCSI_KEVENT_UNBIND_SESSION);
668         ISCSI_DBG_TRANS_SESSION(session, "Completed target removal\n");
669 }
670
671 struct iscsi_cls_session *
672 iscsi_alloc_session(struct Scsi_Host *shost, struct iscsi_transport *transport,
673                     int dd_size)
674 {
675         struct iscsi_cls_session *session;
676
677         session = kzalloc(sizeof(*session) + dd_size,
678                           GFP_KERNEL);
679         if (!session)
680                 return NULL;
681
682         session->transport = transport;
683         session->recovery_tmo = 120;
684         session->state = ISCSI_SESSION_FREE;
685         INIT_DELAYED_WORK(&session->recovery_work, session_recovery_timedout);
686         INIT_LIST_HEAD(&session->sess_list);
687         INIT_WORK(&session->unblock_work, __iscsi_unblock_session);
688         INIT_WORK(&session->block_work, __iscsi_block_session);
689         INIT_WORK(&session->unbind_work, __iscsi_unbind_session);
690         INIT_WORK(&session->scan_work, iscsi_scan_session);
691         spin_lock_init(&session->lock);
692
693         /* this is released in the dev's release function */
694         scsi_host_get(shost);
695         session->dev.parent = &shost->shost_gendev;
696         session->dev.release = iscsi_session_release;
697         device_initialize(&session->dev);
698         if (dd_size)
699                 session->dd_data = &session[1];
700
701         ISCSI_DBG_TRANS_SESSION(session, "Completed session allocation\n");
702         return session;
703 }
704 EXPORT_SYMBOL_GPL(iscsi_alloc_session);
705
706 static int iscsi_get_next_target_id(struct device *dev, void *data)
707 {
708         struct iscsi_cls_session *session;
709         unsigned long flags;
710         int err = 0;
711
712         if (!iscsi_is_session_dev(dev))
713                 return 0;
714
715         session = iscsi_dev_to_session(dev);
716         spin_lock_irqsave(&session->lock, flags);
717         if (*((unsigned int *) data) == session->target_id)
718                 err = -EEXIST;
719         spin_unlock_irqrestore(&session->lock, flags);
720         return err;
721 }
722
723 int iscsi_add_session(struct iscsi_cls_session *session, unsigned int target_id)
724 {
725         struct Scsi_Host *shost = iscsi_session_to_shost(session);
726         struct iscsi_cls_host *ihost;
727         unsigned long flags;
728         unsigned int id = target_id;
729         int err;
730
731         ihost = shost->shost_data;
732         session->sid = atomic_add_return(1, &iscsi_session_nr);
733
734         if (id == ISCSI_MAX_TARGET) {
735                 for (id = 0; id < ISCSI_MAX_TARGET; id++) {
736                         err = device_for_each_child(&shost->shost_gendev, &id,
737                                                     iscsi_get_next_target_id);
738                         if (!err)
739                                 break;
740                 }
741
742                 if (id == ISCSI_MAX_TARGET) {
743                         iscsi_cls_session_printk(KERN_ERR, session,
744                                                  "Too many iscsi targets. Max "
745                                                  "number of targets is %d.\n",
746                                                  ISCSI_MAX_TARGET - 1);
747                         err = -EOVERFLOW;
748                         goto release_host;
749                 }
750         }
751         session->target_id = id;
752
753         dev_set_name(&session->dev, "session%u", session->sid);
754         err = device_add(&session->dev);
755         if (err) {
756                 iscsi_cls_session_printk(KERN_ERR, session,
757                                          "could not register session's dev\n");
758                 goto release_host;
759         }
760         transport_register_device(&session->dev);
761
762         spin_lock_irqsave(&sesslock, flags);
763         list_add(&session->sess_list, &sesslist);
764         spin_unlock_irqrestore(&sesslock, flags);
765
766         iscsi_session_event(session, ISCSI_KEVENT_CREATE_SESSION);
767         ISCSI_DBG_TRANS_SESSION(session, "Completed session adding\n");
768         return 0;
769
770 release_host:
771         scsi_host_put(shost);
772         return err;
773 }
774 EXPORT_SYMBOL_GPL(iscsi_add_session);
775
776 /**
777  * iscsi_create_session - create iscsi class session
778  * @shost: scsi host
779  * @transport: iscsi transport
780  * @dd_size: private driver data size
781  * @target_id: which target
782  *
783  * This can be called from a LLD or iscsi_transport.
784  */
785 struct iscsi_cls_session *
786 iscsi_create_session(struct Scsi_Host *shost, struct iscsi_transport *transport,
787                      int dd_size, unsigned int target_id)
788 {
789         struct iscsi_cls_session *session;
790
791         session = iscsi_alloc_session(shost, transport, dd_size);
792         if (!session)
793                 return NULL;
794
795         if (iscsi_add_session(session, target_id)) {
796                 iscsi_free_session(session);
797                 return NULL;
798         }
799         return session;
800 }
801 EXPORT_SYMBOL_GPL(iscsi_create_session);
802
803 static void iscsi_conn_release(struct device *dev)
804 {
805         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev);
806         struct device *parent = conn->dev.parent;
807
808         ISCSI_DBG_TRANS_CONN(conn, "Releasing conn\n");
809         kfree(conn);
810         put_device(parent);
811 }
812
813 static int iscsi_is_conn_dev(const struct device *dev)
814 {
815         return dev->release == iscsi_conn_release;
816 }
817
818 static int iscsi_iter_destroy_conn_fn(struct device *dev, void *data)
819 {
820         if (!iscsi_is_conn_dev(dev))
821                 return 0;
822         return iscsi_destroy_conn(iscsi_dev_to_conn(dev));
823 }
824
825 void iscsi_remove_session(struct iscsi_cls_session *session)
826 {
827         struct Scsi_Host *shost = iscsi_session_to_shost(session);
828         unsigned long flags;
829         int err;
830
831         ISCSI_DBG_TRANS_SESSION(session, "Removing session\n");
832
833         spin_lock_irqsave(&sesslock, flags);
834         list_del(&session->sess_list);
835         spin_unlock_irqrestore(&sesslock, flags);
836
837         /* make sure there are no blocks/unblocks queued */
838         flush_workqueue(iscsi_eh_timer_workq);
839         /* make sure the timedout callout is not running */
840         if (!cancel_delayed_work(&session->recovery_work))
841                 flush_workqueue(iscsi_eh_timer_workq);
842         /*
843          * If we are blocked let commands flow again. The lld or iscsi
844          * layer should set up the queuecommand to fail commands.
845          * We assume that LLD will not be calling block/unblock while
846          * removing the session.
847          */
848         spin_lock_irqsave(&session->lock, flags);
849         session->state = ISCSI_SESSION_FREE;
850         spin_unlock_irqrestore(&session->lock, flags);
851
852         scsi_target_unblock(&session->dev);
853         /* flush running scans then delete devices */
854         scsi_flush_work(shost);
855         __iscsi_unbind_session(&session->unbind_work);
856
857         /* hw iscsi may not have removed all connections from session */
858         err = device_for_each_child(&session->dev, NULL,
859                                     iscsi_iter_destroy_conn_fn);
860         if (err)
861                 iscsi_cls_session_printk(KERN_ERR, session,
862                                          "Could not delete all connections "
863                                          "for session. Error %d.\n", err);
864
865         transport_unregister_device(&session->dev);
866
867         ISCSI_DBG_TRANS_SESSION(session, "Completing session removal\n");
868         device_del(&session->dev);
869 }
870 EXPORT_SYMBOL_GPL(iscsi_remove_session);
871
872 void iscsi_free_session(struct iscsi_cls_session *session)
873 {
874         ISCSI_DBG_TRANS_SESSION(session, "Freeing session\n");
875         iscsi_session_event(session, ISCSI_KEVENT_DESTROY_SESSION);
876         put_device(&session->dev);
877 }
878 EXPORT_SYMBOL_GPL(iscsi_free_session);
879
880 /**
881  * iscsi_destroy_session - destroy iscsi session
882  * @session: iscsi_session
883  *
884  * Can be called by a LLD or iscsi_transport. There must not be
885  * any running connections.
886  */
887 int iscsi_destroy_session(struct iscsi_cls_session *session)
888 {
889         iscsi_remove_session(session);
890         ISCSI_DBG_TRANS_SESSION(session, "Completing session destruction\n");
891         iscsi_free_session(session);
892         return 0;
893 }
894 EXPORT_SYMBOL_GPL(iscsi_destroy_session);
895
896 /**
897  * iscsi_create_conn - create iscsi class connection
898  * @session: iscsi cls session
899  * @dd_size: private driver data size
900  * @cid: connection id
901  *
902  * This can be called from a LLD or iscsi_transport. The connection
903  * is child of the session so cid must be unique for all connections
904  * on the session.
905  *
906  * Since we do not support MCS, cid will normally be zero. In some cases
907  * for software iscsi we could be trying to preallocate a connection struct
908  * in which case there could be two connection structs and cid would be
909  * non-zero.
910  */
911 struct iscsi_cls_conn *
912 iscsi_create_conn(struct iscsi_cls_session *session, int dd_size, uint32_t cid)
913 {
914         struct iscsi_transport *transport = session->transport;
915         struct iscsi_cls_conn *conn;
916         unsigned long flags;
917         int err;
918
919         conn = kzalloc(sizeof(*conn) + dd_size, GFP_KERNEL);
920         if (!conn)
921                 return NULL;
922         if (dd_size)
923                 conn->dd_data = &conn[1];
924
925         INIT_LIST_HEAD(&conn->conn_list);
926         conn->transport = transport;
927         conn->cid = cid;
928
929         /* this is released in the dev's release function */
930         if (!get_device(&session->dev))
931                 goto free_conn;
932
933         dev_set_name(&conn->dev, "connection%d:%u", session->sid, cid);
934         conn->dev.parent = &session->dev;
935         conn->dev.release = iscsi_conn_release;
936         err = device_register(&conn->dev);
937         if (err) {
938                 iscsi_cls_session_printk(KERN_ERR, session, "could not "
939                                          "register connection's dev\n");
940                 goto release_parent_ref;
941         }
942         transport_register_device(&conn->dev);
943
944         spin_lock_irqsave(&connlock, flags);
945         list_add(&conn->conn_list, &connlist);
946         conn->active = 1;
947         spin_unlock_irqrestore(&connlock, flags);
948
949         ISCSI_DBG_TRANS_CONN(conn, "Completed conn creation\n");
950         return conn;
951
952 release_parent_ref:
953         put_device(&session->dev);
954 free_conn:
955         kfree(conn);
956         return NULL;
957 }
958
959 EXPORT_SYMBOL_GPL(iscsi_create_conn);
960
961 /**
962  * iscsi_destroy_conn - destroy iscsi class connection
963  * @conn: iscsi cls session
964  *
965  * This can be called from a LLD or iscsi_transport.
966  */
967 int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
968 {
969         unsigned long flags;
970
971         spin_lock_irqsave(&connlock, flags);
972         conn->active = 0;
973         list_del(&conn->conn_list);
974         spin_unlock_irqrestore(&connlock, flags);
975
976         transport_unregister_device(&conn->dev);
977         ISCSI_DBG_TRANS_CONN(conn, "Completing conn destruction\n");
978         device_unregister(&conn->dev);
979         return 0;
980 }
981 EXPORT_SYMBOL_GPL(iscsi_destroy_conn);
982
983 /*
984  * iscsi interface functions
985  */
986 static struct iscsi_internal *
987 iscsi_if_transport_lookup(struct iscsi_transport *tt)
988 {
989         struct iscsi_internal *priv;
990         unsigned long flags;
991
992         spin_lock_irqsave(&iscsi_transport_lock, flags);
993         list_for_each_entry(priv, &iscsi_transports, list) {
994                 if (tt == priv->iscsi_transport) {
995                         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
996                         return priv;
997                 }
998         }
999         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1000         return NULL;
1001 }
1002
1003 static int
1004 iscsi_multicast_skb(struct sk_buff *skb, uint32_t group, gfp_t gfp)
1005 {
1006         return nlmsg_multicast(nls, skb, 0, group, gfp);
1007 }
1008
1009 int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
1010                    char *data, uint32_t data_size)
1011 {
1012         struct nlmsghdr *nlh;
1013         struct sk_buff *skb;
1014         struct iscsi_uevent *ev;
1015         char *pdu;
1016         struct iscsi_internal *priv;
1017         int len = NLMSG_SPACE(sizeof(*ev) + sizeof(struct iscsi_hdr) +
1018                               data_size);
1019
1020         priv = iscsi_if_transport_lookup(conn->transport);
1021         if (!priv)
1022                 return -EINVAL;
1023
1024         skb = alloc_skb(len, GFP_ATOMIC);
1025         if (!skb) {
1026                 iscsi_conn_error_event(conn, ISCSI_ERR_CONN_FAILED);
1027                 iscsi_cls_conn_printk(KERN_ERR, conn, "can not deliver "
1028                                       "control PDU: OOM\n");
1029                 return -ENOMEM;
1030         }
1031
1032         nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1033         ev = NLMSG_DATA(nlh);
1034         memset(ev, 0, sizeof(*ev));
1035         ev->transport_handle = iscsi_handle(conn->transport);
1036         ev->type = ISCSI_KEVENT_RECV_PDU;
1037         ev->r.recv_req.cid = conn->cid;
1038         ev->r.recv_req.sid = iscsi_conn_get_sid(conn);
1039         pdu = (char*)ev + sizeof(*ev);
1040         memcpy(pdu, hdr, sizeof(struct iscsi_hdr));
1041         memcpy(pdu + sizeof(struct iscsi_hdr), data, data_size);
1042
1043         return iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_ATOMIC);
1044 }
1045 EXPORT_SYMBOL_GPL(iscsi_recv_pdu);
1046
1047 int iscsi_offload_mesg(struct Scsi_Host *shost,
1048                        struct iscsi_transport *transport, uint32_t type,
1049                        char *data, uint16_t data_size)
1050 {
1051         struct nlmsghdr *nlh;
1052         struct sk_buff *skb;
1053         struct iscsi_uevent *ev;
1054         int len = NLMSG_SPACE(sizeof(*ev) + data_size);
1055
1056         skb = alloc_skb(len, GFP_ATOMIC);
1057         if (!skb) {
1058                 printk(KERN_ERR "can not deliver iscsi offload message:OOM\n");
1059                 return -ENOMEM;
1060         }
1061
1062         nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1063         ev = NLMSG_DATA(nlh);
1064         memset(ev, 0, sizeof(*ev));
1065         ev->type = type;
1066         ev->transport_handle = iscsi_handle(transport);
1067         switch (type) {
1068         case ISCSI_KEVENT_PATH_REQ:
1069                 ev->r.req_path.host_no = shost->host_no;
1070                 break;
1071         case ISCSI_KEVENT_IF_DOWN:
1072                 ev->r.notify_if_down.host_no = shost->host_no;
1073                 break;
1074         }
1075
1076         memcpy((char *)ev + sizeof(*ev), data, data_size);
1077
1078         return iscsi_multicast_skb(skb, ISCSI_NL_GRP_UIP, GFP_ATOMIC);
1079 }
1080 EXPORT_SYMBOL_GPL(iscsi_offload_mesg);
1081
1082 void iscsi_conn_error_event(struct iscsi_cls_conn *conn, enum iscsi_err error)
1083 {
1084         struct nlmsghdr *nlh;
1085         struct sk_buff  *skb;
1086         struct iscsi_uevent *ev;
1087         struct iscsi_internal *priv;
1088         int len = NLMSG_SPACE(sizeof(*ev));
1089
1090         priv = iscsi_if_transport_lookup(conn->transport);
1091         if (!priv)
1092                 return;
1093
1094         skb = alloc_skb(len, GFP_ATOMIC);
1095         if (!skb) {
1096                 iscsi_cls_conn_printk(KERN_ERR, conn, "gracefully ignored "
1097                                       "conn error (%d)\n", error);
1098                 return;
1099         }
1100
1101         nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1102         ev = NLMSG_DATA(nlh);
1103         ev->transport_handle = iscsi_handle(conn->transport);
1104         ev->type = ISCSI_KEVENT_CONN_ERROR;
1105         ev->r.connerror.error = error;
1106         ev->r.connerror.cid = conn->cid;
1107         ev->r.connerror.sid = iscsi_conn_get_sid(conn);
1108
1109         iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_ATOMIC);
1110
1111         iscsi_cls_conn_printk(KERN_INFO, conn, "detected conn error (%d)\n",
1112                               error);
1113 }
1114 EXPORT_SYMBOL_GPL(iscsi_conn_error_event);
1115
1116 static int
1117 iscsi_if_send_reply(uint32_t group, int seq, int type, int done, int multi,
1118                     void *payload, int size)
1119 {
1120         struct sk_buff  *skb;
1121         struct nlmsghdr *nlh;
1122         int len = NLMSG_SPACE(size);
1123         int flags = multi ? NLM_F_MULTI : 0;
1124         int t = done ? NLMSG_DONE : type;
1125
1126         skb = alloc_skb(len, GFP_ATOMIC);
1127         if (!skb) {
1128                 printk(KERN_ERR "Could not allocate skb to send reply.\n");
1129                 return -ENOMEM;
1130         }
1131
1132         nlh = __nlmsg_put(skb, 0, 0, t, (len - sizeof(*nlh)), 0);
1133         nlh->nlmsg_flags = flags;
1134         memcpy(NLMSG_DATA(nlh), payload, size);
1135         return iscsi_multicast_skb(skb, group, GFP_ATOMIC);
1136 }
1137
1138 static int
1139 iscsi_if_get_stats(struct iscsi_transport *transport, struct nlmsghdr *nlh)
1140 {
1141         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1142         struct iscsi_stats *stats;
1143         struct sk_buff *skbstat;
1144         struct iscsi_cls_conn *conn;
1145         struct nlmsghdr *nlhstat;
1146         struct iscsi_uevent *evstat;
1147         struct iscsi_internal *priv;
1148         int len = NLMSG_SPACE(sizeof(*ev) +
1149                               sizeof(struct iscsi_stats) +
1150                               sizeof(struct iscsi_stats_custom) *
1151                               ISCSI_STATS_CUSTOM_MAX);
1152         int err = 0;
1153
1154         priv = iscsi_if_transport_lookup(transport);
1155         if (!priv)
1156                 return -EINVAL;
1157
1158         conn = iscsi_conn_lookup(ev->u.get_stats.sid, ev->u.get_stats.cid);
1159         if (!conn)
1160                 return -EEXIST;
1161
1162         do {
1163                 int actual_size;
1164
1165                 skbstat = alloc_skb(len, GFP_ATOMIC);
1166                 if (!skbstat) {
1167                         iscsi_cls_conn_printk(KERN_ERR, conn, "can not "
1168                                               "deliver stats: OOM\n");
1169                         return -ENOMEM;
1170                 }
1171
1172                 nlhstat = __nlmsg_put(skbstat, 0, 0, 0,
1173                                       (len - sizeof(*nlhstat)), 0);
1174                 evstat = NLMSG_DATA(nlhstat);
1175                 memset(evstat, 0, sizeof(*evstat));
1176                 evstat->transport_handle = iscsi_handle(conn->transport);
1177                 evstat->type = nlh->nlmsg_type;
1178                 evstat->u.get_stats.cid =
1179                         ev->u.get_stats.cid;
1180                 evstat->u.get_stats.sid =
1181                         ev->u.get_stats.sid;
1182                 stats = (struct iscsi_stats *)
1183                         ((char*)evstat + sizeof(*evstat));
1184                 memset(stats, 0, sizeof(*stats));
1185
1186                 transport->get_stats(conn, stats);
1187                 actual_size = NLMSG_SPACE(sizeof(struct iscsi_uevent) +
1188                                           sizeof(struct iscsi_stats) +
1189                                           sizeof(struct iscsi_stats_custom) *
1190                                           stats->custom_length);
1191                 actual_size -= sizeof(*nlhstat);
1192                 actual_size = NLMSG_LENGTH(actual_size);
1193                 skb_trim(skbstat, NLMSG_ALIGN(actual_size));
1194                 nlhstat->nlmsg_len = actual_size;
1195
1196                 err = iscsi_multicast_skb(skbstat, ISCSI_NL_GRP_ISCSID,
1197                                           GFP_ATOMIC);
1198         } while (err < 0 && err != -ECONNREFUSED);
1199
1200         return err;
1201 }
1202
1203 /**
1204  * iscsi_session_event - send session destr. completion event
1205  * @session: iscsi class session
1206  * @event: type of event
1207  */
1208 int iscsi_session_event(struct iscsi_cls_session *session,
1209                         enum iscsi_uevent_e event)
1210 {
1211         struct iscsi_internal *priv;
1212         struct Scsi_Host *shost;
1213         struct iscsi_uevent *ev;
1214         struct sk_buff  *skb;
1215         struct nlmsghdr *nlh;
1216         int rc, len = NLMSG_SPACE(sizeof(*ev));
1217
1218         priv = iscsi_if_transport_lookup(session->transport);
1219         if (!priv)
1220                 return -EINVAL;
1221         shost = iscsi_session_to_shost(session);
1222
1223         skb = alloc_skb(len, GFP_KERNEL);
1224         if (!skb) {
1225                 iscsi_cls_session_printk(KERN_ERR, session,
1226                                          "Cannot notify userspace of session "
1227                                          "event %u\n", event);
1228                 return -ENOMEM;
1229         }
1230
1231         nlh = __nlmsg_put(skb, 0, 0, 0, (len - sizeof(*nlh)), 0);
1232         ev = NLMSG_DATA(nlh);
1233         ev->transport_handle = iscsi_handle(session->transport);
1234
1235         ev->type = event;
1236         switch (event) {
1237         case ISCSI_KEVENT_DESTROY_SESSION:
1238                 ev->r.d_session.host_no = shost->host_no;
1239                 ev->r.d_session.sid = session->sid;
1240                 break;
1241         case ISCSI_KEVENT_CREATE_SESSION:
1242                 ev->r.c_session_ret.host_no = shost->host_no;
1243                 ev->r.c_session_ret.sid = session->sid;
1244                 break;
1245         case ISCSI_KEVENT_UNBIND_SESSION:
1246                 ev->r.unbind_session.host_no = shost->host_no;
1247                 ev->r.unbind_session.sid = session->sid;
1248                 break;
1249         default:
1250                 iscsi_cls_session_printk(KERN_ERR, session, "Invalid event "
1251                                          "%u.\n", event);
1252                 kfree_skb(skb);
1253                 return -EINVAL;
1254         }
1255
1256         /*
1257          * this will occur if the daemon is not up, so we just warn
1258          * the user and when the daemon is restarted it will handle it
1259          */
1260         rc = iscsi_multicast_skb(skb, ISCSI_NL_GRP_ISCSID, GFP_KERNEL);
1261         if (rc == -ESRCH)
1262                 iscsi_cls_session_printk(KERN_ERR, session,
1263                                          "Cannot notify userspace of session "
1264                                          "event %u. Check iscsi daemon\n",
1265                                          event);
1266
1267         ISCSI_DBG_TRANS_SESSION(session, "Completed handling event %d rc %d\n",
1268                                 event, rc);
1269         return rc;
1270 }
1271 EXPORT_SYMBOL_GPL(iscsi_session_event);
1272
1273 static int
1274 iscsi_if_create_session(struct iscsi_internal *priv, struct iscsi_endpoint *ep,
1275                         struct iscsi_uevent *ev, uint32_t initial_cmdsn,
1276                         uint16_t cmds_max, uint16_t queue_depth)
1277 {
1278         struct iscsi_transport *transport = priv->iscsi_transport;
1279         struct iscsi_cls_session *session;
1280         struct Scsi_Host *shost;
1281
1282         session = transport->create_session(ep, cmds_max, queue_depth,
1283                                             initial_cmdsn);
1284         if (!session)
1285                 return -ENOMEM;
1286
1287         shost = iscsi_session_to_shost(session);
1288         ev->r.c_session_ret.host_no = shost->host_no;
1289         ev->r.c_session_ret.sid = session->sid;
1290         ISCSI_DBG_TRANS_SESSION(session,
1291                                 "Completed creating transport session\n");
1292         return 0;
1293 }
1294
1295 static int
1296 iscsi_if_create_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1297 {
1298         struct iscsi_cls_conn *conn;
1299         struct iscsi_cls_session *session;
1300
1301         session = iscsi_session_lookup(ev->u.c_conn.sid);
1302         if (!session) {
1303                 printk(KERN_ERR "iscsi: invalid session %d.\n",
1304                        ev->u.c_conn.sid);
1305                 return -EINVAL;
1306         }
1307
1308         conn = transport->create_conn(session, ev->u.c_conn.cid);
1309         if (!conn) {
1310                 iscsi_cls_session_printk(KERN_ERR, session,
1311                                          "couldn't create a new connection.");
1312                 return -ENOMEM;
1313         }
1314
1315         ev->r.c_conn_ret.sid = session->sid;
1316         ev->r.c_conn_ret.cid = conn->cid;
1317
1318         ISCSI_DBG_TRANS_CONN(conn, "Completed creating transport conn\n");
1319         return 0;
1320 }
1321
1322 static int
1323 iscsi_if_destroy_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1324 {
1325         struct iscsi_cls_conn *conn;
1326
1327         conn = iscsi_conn_lookup(ev->u.d_conn.sid, ev->u.d_conn.cid);
1328         if (!conn)
1329                 return -EINVAL;
1330
1331         ISCSI_DBG_TRANS_CONN(conn, "Destroying transport conn\n");
1332         if (transport->destroy_conn)
1333                 transport->destroy_conn(conn);
1334
1335         return 0;
1336 }
1337
1338 static int
1339 iscsi_set_param(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1340 {
1341         char *data = (char*)ev + sizeof(*ev);
1342         struct iscsi_cls_conn *conn;
1343         struct iscsi_cls_session *session;
1344         int err = 0, value = 0;
1345
1346         session = iscsi_session_lookup(ev->u.set_param.sid);
1347         conn = iscsi_conn_lookup(ev->u.set_param.sid, ev->u.set_param.cid);
1348         if (!conn || !session)
1349                 return -EINVAL;
1350
1351         switch (ev->u.set_param.param) {
1352         case ISCSI_PARAM_SESS_RECOVERY_TMO:
1353                 sscanf(data, "%d", &value);
1354                 session->recovery_tmo = value;
1355                 break;
1356         default:
1357                 err = transport->set_param(conn, ev->u.set_param.param,
1358                                            data, ev->u.set_param.len);
1359         }
1360
1361         return err;
1362 }
1363
1364 static int iscsi_if_ep_connect(struct iscsi_transport *transport,
1365                                struct iscsi_uevent *ev, int msg_type)
1366 {
1367         struct iscsi_endpoint *ep;
1368         struct sockaddr *dst_addr;
1369         struct Scsi_Host *shost = NULL;
1370         int non_blocking, err = 0;
1371
1372         if (!transport->ep_connect)
1373                 return -EINVAL;
1374
1375         if (msg_type == ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST) {
1376                 shost = scsi_host_lookup(ev->u.ep_connect_through_host.host_no);
1377                 if (!shost) {
1378                         printk(KERN_ERR "ep connect failed. Could not find "
1379                                "host no %u\n",
1380                                ev->u.ep_connect_through_host.host_no);
1381                         return -ENODEV;
1382                 }
1383                 non_blocking = ev->u.ep_connect_through_host.non_blocking;
1384         } else
1385                 non_blocking = ev->u.ep_connect.non_blocking;
1386
1387         dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1388         ep = transport->ep_connect(shost, dst_addr, non_blocking);
1389         if (IS_ERR(ep)) {
1390                 err = PTR_ERR(ep);
1391                 goto release_host;
1392         }
1393
1394         ev->r.ep_connect_ret.handle = ep->id;
1395 release_host:
1396         if (shost)
1397                 scsi_host_put(shost);
1398         return err;
1399 }
1400
1401 static int
1402 iscsi_if_transport_ep(struct iscsi_transport *transport,
1403                       struct iscsi_uevent *ev, int msg_type)
1404 {
1405         struct iscsi_endpoint *ep;
1406         int rc = 0;
1407
1408         switch (msg_type) {
1409         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST:
1410         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1411                 rc = iscsi_if_ep_connect(transport, ev, msg_type);
1412                 break;
1413         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1414                 if (!transport->ep_poll)
1415                         return -EINVAL;
1416
1417                 ep = iscsi_lookup_endpoint(ev->u.ep_poll.ep_handle);
1418                 if (!ep)
1419                         return -EINVAL;
1420
1421                 ev->r.retcode = transport->ep_poll(ep,
1422                                                    ev->u.ep_poll.timeout_ms);
1423                 break;
1424         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1425                 if (!transport->ep_disconnect)
1426                         return -EINVAL;
1427
1428                 ep = iscsi_lookup_endpoint(ev->u.ep_disconnect.ep_handle);
1429                 if (!ep)
1430                         return -EINVAL;
1431
1432                 transport->ep_disconnect(ep);
1433                 break;
1434         }
1435         return rc;
1436 }
1437
1438 static int
1439 iscsi_tgt_dscvr(struct iscsi_transport *transport,
1440                 struct iscsi_uevent *ev)
1441 {
1442         struct Scsi_Host *shost;
1443         struct sockaddr *dst_addr;
1444         int err;
1445
1446         if (!transport->tgt_dscvr)
1447                 return -EINVAL;
1448
1449         shost = scsi_host_lookup(ev->u.tgt_dscvr.host_no);
1450         if (!shost) {
1451                 printk(KERN_ERR "target discovery could not find host no %u\n",
1452                        ev->u.tgt_dscvr.host_no);
1453                 return -ENODEV;
1454         }
1455
1456
1457         dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
1458         err = transport->tgt_dscvr(shost, ev->u.tgt_dscvr.type,
1459                                    ev->u.tgt_dscvr.enable, dst_addr);
1460         scsi_host_put(shost);
1461         return err;
1462 }
1463
1464 static int
1465 iscsi_set_host_param(struct iscsi_transport *transport,
1466                      struct iscsi_uevent *ev)
1467 {
1468         char *data = (char*)ev + sizeof(*ev);
1469         struct Scsi_Host *shost;
1470         int err;
1471
1472         if (!transport->set_host_param)
1473                 return -ENOSYS;
1474
1475         shost = scsi_host_lookup(ev->u.set_host_param.host_no);
1476         if (!shost) {
1477                 printk(KERN_ERR "set_host_param could not find host no %u\n",
1478                        ev->u.set_host_param.host_no);
1479                 return -ENODEV;
1480         }
1481
1482         err = transport->set_host_param(shost, ev->u.set_host_param.param,
1483                                         data, ev->u.set_host_param.len);
1484         scsi_host_put(shost);
1485         return err;
1486 }
1487
1488 static int
1489 iscsi_set_path(struct iscsi_transport *transport, struct iscsi_uevent *ev)
1490 {
1491         struct Scsi_Host *shost;
1492         struct iscsi_path *params;
1493         int err;
1494
1495         if (!transport->set_path)
1496                 return -ENOSYS;
1497
1498         shost = scsi_host_lookup(ev->u.set_path.host_no);
1499         if (!shost) {
1500                 printk(KERN_ERR "set path could not find host no %u\n",
1501                        ev->u.set_path.host_no);
1502                 return -ENODEV;
1503         }
1504
1505         params = (struct iscsi_path *)((char *)ev + sizeof(*ev));
1506         err = transport->set_path(shost, params);
1507
1508         scsi_host_put(shost);
1509         return err;
1510 }
1511
1512 static int
1513 iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, uint32_t *group)
1514 {
1515         int err = 0;
1516         struct iscsi_uevent *ev = NLMSG_DATA(nlh);
1517         struct iscsi_transport *transport = NULL;
1518         struct iscsi_internal *priv;
1519         struct iscsi_cls_session *session;
1520         struct iscsi_cls_conn *conn;
1521         struct iscsi_endpoint *ep = NULL;
1522
1523         if (nlh->nlmsg_type == ISCSI_UEVENT_PATH_UPDATE)
1524                 *group = ISCSI_NL_GRP_UIP;
1525         else
1526                 *group = ISCSI_NL_GRP_ISCSID;
1527
1528         priv = iscsi_if_transport_lookup(iscsi_ptr(ev->transport_handle));
1529         if (!priv)
1530                 return -EINVAL;
1531         transport = priv->iscsi_transport;
1532
1533         if (!try_module_get(transport->owner))
1534                 return -EINVAL;
1535
1536         switch (nlh->nlmsg_type) {
1537         case ISCSI_UEVENT_CREATE_SESSION:
1538                 err = iscsi_if_create_session(priv, ep, ev,
1539                                               ev->u.c_session.initial_cmdsn,
1540                                               ev->u.c_session.cmds_max,
1541                                               ev->u.c_session.queue_depth);
1542                 break;
1543         case ISCSI_UEVENT_CREATE_BOUND_SESSION:
1544                 ep = iscsi_lookup_endpoint(ev->u.c_bound_session.ep_handle);
1545                 if (!ep) {
1546                         err = -EINVAL;
1547                         break;
1548                 }
1549
1550                 err = iscsi_if_create_session(priv, ep, ev,
1551                                         ev->u.c_bound_session.initial_cmdsn,
1552                                         ev->u.c_bound_session.cmds_max,
1553                                         ev->u.c_bound_session.queue_depth);
1554                 break;
1555         case ISCSI_UEVENT_DESTROY_SESSION:
1556                 session = iscsi_session_lookup(ev->u.d_session.sid);
1557                 if (session)
1558                         transport->destroy_session(session);
1559                 else
1560                         err = -EINVAL;
1561                 break;
1562         case ISCSI_UEVENT_UNBIND_SESSION:
1563                 session = iscsi_session_lookup(ev->u.d_session.sid);
1564                 if (session)
1565                         scsi_queue_work(iscsi_session_to_shost(session),
1566                                         &session->unbind_work);
1567                 else
1568                         err = -EINVAL;
1569                 break;
1570         case ISCSI_UEVENT_CREATE_CONN:
1571                 err = iscsi_if_create_conn(transport, ev);
1572                 break;
1573         case ISCSI_UEVENT_DESTROY_CONN:
1574                 err = iscsi_if_destroy_conn(transport, ev);
1575                 break;
1576         case ISCSI_UEVENT_BIND_CONN:
1577                 session = iscsi_session_lookup(ev->u.b_conn.sid);
1578                 conn = iscsi_conn_lookup(ev->u.b_conn.sid, ev->u.b_conn.cid);
1579
1580                 if (session && conn)
1581                         ev->r.retcode = transport->bind_conn(session, conn,
1582                                         ev->u.b_conn.transport_eph,
1583                                         ev->u.b_conn.is_leading);
1584                 else
1585                         err = -EINVAL;
1586                 break;
1587         case ISCSI_UEVENT_SET_PARAM:
1588                 err = iscsi_set_param(transport, ev);
1589                 break;
1590         case ISCSI_UEVENT_START_CONN:
1591                 conn = iscsi_conn_lookup(ev->u.start_conn.sid, ev->u.start_conn.cid);
1592                 if (conn)
1593                         ev->r.retcode = transport->start_conn(conn);
1594                 else
1595                         err = -EINVAL;
1596                 break;
1597         case ISCSI_UEVENT_STOP_CONN:
1598                 conn = iscsi_conn_lookup(ev->u.stop_conn.sid, ev->u.stop_conn.cid);
1599                 if (conn)
1600                         transport->stop_conn(conn, ev->u.stop_conn.flag);
1601                 else
1602                         err = -EINVAL;
1603                 break;
1604         case ISCSI_UEVENT_SEND_PDU:
1605                 conn = iscsi_conn_lookup(ev->u.send_pdu.sid, ev->u.send_pdu.cid);
1606                 if (conn)
1607                         ev->r.retcode = transport->send_pdu(conn,
1608                                 (struct iscsi_hdr*)((char*)ev + sizeof(*ev)),
1609                                 (char*)ev + sizeof(*ev) + ev->u.send_pdu.hdr_size,
1610                                 ev->u.send_pdu.data_size);
1611                 else
1612                         err = -EINVAL;
1613                 break;
1614         case ISCSI_UEVENT_GET_STATS:
1615                 err = iscsi_if_get_stats(transport, nlh);
1616                 break;
1617         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
1618         case ISCSI_UEVENT_TRANSPORT_EP_POLL:
1619         case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
1620         case ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST:
1621                 err = iscsi_if_transport_ep(transport, ev, nlh->nlmsg_type);
1622                 break;
1623         case ISCSI_UEVENT_TGT_DSCVR:
1624                 err = iscsi_tgt_dscvr(transport, ev);
1625                 break;
1626         case ISCSI_UEVENT_SET_HOST_PARAM:
1627                 err = iscsi_set_host_param(transport, ev);
1628                 break;
1629         case ISCSI_UEVENT_PATH_UPDATE:
1630                 err = iscsi_set_path(transport, ev);
1631                 break;
1632         default:
1633                 err = -ENOSYS;
1634                 break;
1635         }
1636
1637         module_put(transport->owner);
1638         return err;
1639 }
1640
1641 /*
1642  * Get message from skb.  Each message is processed by iscsi_if_recv_msg.
1643  * Malformed skbs with wrong lengths or invalid creds are not processed.
1644  */
1645 static void
1646 iscsi_if_rx(struct sk_buff *skb)
1647 {
1648         mutex_lock(&rx_queue_mutex);
1649         while (skb->len >= NLMSG_SPACE(0)) {
1650                 int err;
1651                 uint32_t rlen;
1652                 struct nlmsghdr *nlh;
1653                 struct iscsi_uevent *ev;
1654                 uint32_t group;
1655
1656                 nlh = nlmsg_hdr(skb);
1657                 if (nlh->nlmsg_len < sizeof(*nlh) ||
1658                     skb->len < nlh->nlmsg_len) {
1659                         break;
1660                 }
1661
1662                 ev = NLMSG_DATA(nlh);
1663                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
1664                 if (rlen > skb->len)
1665                         rlen = skb->len;
1666
1667                 err = iscsi_if_recv_msg(skb, nlh, &group);
1668                 if (err) {
1669                         ev->type = ISCSI_KEVENT_IF_ERROR;
1670                         ev->iferror = err;
1671                 }
1672                 do {
1673                         /*
1674                          * special case for GET_STATS:
1675                          * on success - sending reply and stats from
1676                          * inside of if_recv_msg(),
1677                          * on error - fall through.
1678                          */
1679                         if (ev->type == ISCSI_UEVENT_GET_STATS && !err)
1680                                 break;
1681                         err = iscsi_if_send_reply(group, nlh->nlmsg_seq,
1682                                 nlh->nlmsg_type, 0, 0, ev, sizeof(*ev));
1683                 } while (err < 0 && err != -ECONNREFUSED);
1684                 skb_pull(skb, rlen);
1685         }
1686         mutex_unlock(&rx_queue_mutex);
1687 }
1688
1689 #define ISCSI_CLASS_ATTR(_prefix,_name,_mode,_show,_store)              \
1690 struct device_attribute dev_attr_##_prefix##_##_name =  \
1691         __ATTR(_name,_mode,_show,_store)
1692
1693 /*
1694  * iSCSI connection attrs
1695  */
1696 #define iscsi_conn_attr_show(param)                                     \
1697 static ssize_t                                                          \
1698 show_conn_param_##param(struct device *dev,                             \
1699                         struct device_attribute *attr, char *buf)       \
1700 {                                                                       \
1701         struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev->parent);   \
1702         struct iscsi_transport *t = conn->transport;                    \
1703         return t->get_conn_param(conn, param, buf);                     \
1704 }
1705
1706 #define iscsi_conn_attr(field, param)                                   \
1707         iscsi_conn_attr_show(param)                                     \
1708 static ISCSI_CLASS_ATTR(conn, field, S_IRUGO, show_conn_param_##param,  \
1709                         NULL);
1710
1711 iscsi_conn_attr(max_recv_dlength, ISCSI_PARAM_MAX_RECV_DLENGTH);
1712 iscsi_conn_attr(max_xmit_dlength, ISCSI_PARAM_MAX_XMIT_DLENGTH);
1713 iscsi_conn_attr(header_digest, ISCSI_PARAM_HDRDGST_EN);
1714 iscsi_conn_attr(data_digest, ISCSI_PARAM_DATADGST_EN);
1715 iscsi_conn_attr(ifmarker, ISCSI_PARAM_IFMARKER_EN);
1716 iscsi_conn_attr(ofmarker, ISCSI_PARAM_OFMARKER_EN);
1717 iscsi_conn_attr(persistent_port, ISCSI_PARAM_PERSISTENT_PORT);
1718 iscsi_conn_attr(port, ISCSI_PARAM_CONN_PORT);
1719 iscsi_conn_attr(exp_statsn, ISCSI_PARAM_EXP_STATSN);
1720 iscsi_conn_attr(persistent_address, ISCSI_PARAM_PERSISTENT_ADDRESS);
1721 iscsi_conn_attr(address, ISCSI_PARAM_CONN_ADDRESS);
1722 iscsi_conn_attr(ping_tmo, ISCSI_PARAM_PING_TMO);
1723 iscsi_conn_attr(recv_tmo, ISCSI_PARAM_RECV_TMO);
1724
1725 /*
1726  * iSCSI session attrs
1727  */
1728 #define iscsi_session_attr_show(param, perm)                            \
1729 static ssize_t                                                          \
1730 show_session_param_##param(struct device *dev,                          \
1731                            struct device_attribute *attr, char *buf)    \
1732 {                                                                       \
1733         struct iscsi_cls_session *session =                             \
1734                 iscsi_dev_to_session(dev->parent);                      \
1735         struct iscsi_transport *t = session->transport;                 \
1736                                                                         \
1737         if (perm && !capable(CAP_SYS_ADMIN))                            \
1738                 return -EACCES;                                         \
1739         return t->get_session_param(session, param, buf);               \
1740 }
1741
1742 #define iscsi_session_attr(field, param, perm)                          \
1743         iscsi_session_attr_show(param, perm)                            \
1744 static ISCSI_CLASS_ATTR(sess, field, S_IRUGO, show_session_param_##param, \
1745                         NULL);
1746
1747 iscsi_session_attr(targetname, ISCSI_PARAM_TARGET_NAME, 0);
1748 iscsi_session_attr(initial_r2t, ISCSI_PARAM_INITIAL_R2T_EN, 0);
1749 iscsi_session_attr(max_outstanding_r2t, ISCSI_PARAM_MAX_R2T, 0);
1750 iscsi_session_attr(immediate_data, ISCSI_PARAM_IMM_DATA_EN, 0);
1751 iscsi_session_attr(first_burst_len, ISCSI_PARAM_FIRST_BURST, 0);
1752 iscsi_session_attr(max_burst_len, ISCSI_PARAM_MAX_BURST, 0);
1753 iscsi_session_attr(data_pdu_in_order, ISCSI_PARAM_PDU_INORDER_EN, 0);
1754 iscsi_session_attr(data_seq_in_order, ISCSI_PARAM_DATASEQ_INORDER_EN, 0);
1755 iscsi_session_attr(erl, ISCSI_PARAM_ERL, 0);
1756 iscsi_session_attr(tpgt, ISCSI_PARAM_TPGT, 0);
1757 iscsi_session_attr(username, ISCSI_PARAM_USERNAME, 1);
1758 iscsi_session_attr(username_in, ISCSI_PARAM_USERNAME_IN, 1);
1759 iscsi_session_attr(password, ISCSI_PARAM_PASSWORD, 1);
1760 iscsi_session_attr(password_in, ISCSI_PARAM_PASSWORD_IN, 1);
1761 iscsi_session_attr(fast_abort, ISCSI_PARAM_FAST_ABORT, 0);
1762 iscsi_session_attr(abort_tmo, ISCSI_PARAM_ABORT_TMO, 0);
1763 iscsi_session_attr(lu_reset_tmo, ISCSI_PARAM_LU_RESET_TMO, 0);
1764 iscsi_session_attr(tgt_reset_tmo, ISCSI_PARAM_TGT_RESET_TMO, 0);
1765 iscsi_session_attr(ifacename, ISCSI_PARAM_IFACE_NAME, 0);
1766 iscsi_session_attr(initiatorname, ISCSI_PARAM_INITIATOR_NAME, 0);
1767 iscsi_session_attr(targetalias, ISCSI_PARAM_TARGET_ALIAS, 0);
1768
1769 static ssize_t
1770 show_priv_session_state(struct device *dev, struct device_attribute *attr,
1771                         char *buf)
1772 {
1773         struct iscsi_cls_session *session = iscsi_dev_to_session(dev->parent);
1774         return sprintf(buf, "%s\n", iscsi_session_state_name(session->state));
1775 }
1776 static ISCSI_CLASS_ATTR(priv_sess, state, S_IRUGO, show_priv_session_state,
1777                         NULL);
1778
1779 #define iscsi_priv_session_attr_show(field, format)                     \
1780 static ssize_t                                                          \
1781 show_priv_session_##field(struct device *dev,                           \
1782                           struct device_attribute *attr, char *buf)     \
1783 {                                                                       \
1784         struct iscsi_cls_session *session =                             \
1785                         iscsi_dev_to_session(dev->parent);              \
1786         if (session->field == -1)                                       \
1787                 return sprintf(buf, "off\n");                           \
1788         return sprintf(buf, format"\n", session->field);                \
1789 }
1790
1791 #define iscsi_priv_session_attr_store(field)                            \
1792 static ssize_t                                                          \
1793 store_priv_session_##field(struct device *dev,                          \
1794                            struct device_attribute *attr,               \
1795                            const char *buf, size_t count)               \
1796 {                                                                       \
1797         int val;                                                        \
1798         char *cp;                                                       \
1799         struct iscsi_cls_session *session =                             \
1800                 iscsi_dev_to_session(dev->parent);                      \
1801         if ((session->state == ISCSI_SESSION_FREE) ||                   \
1802             (session->state == ISCSI_SESSION_FAILED))                   \
1803                 return -EBUSY;                                          \
1804         if (strncmp(buf, "off", 3) == 0)                                \
1805                 session->field = -1;                                    \
1806         else {                                                          \
1807                 val = simple_strtoul(buf, &cp, 0);                      \
1808                 if (*cp != '\0' && *cp != '\n')                         \
1809                         return -EINVAL;                                 \
1810                 session->field = val;                                   \
1811         }                                                               \
1812         return count;                                                   \
1813 }
1814
1815 #define iscsi_priv_session_rw_attr(field, format)                       \
1816         iscsi_priv_session_attr_show(field, format)                     \
1817         iscsi_priv_session_attr_store(field)                            \
1818 static ISCSI_CLASS_ATTR(priv_sess, field, S_IRUGO | S_IWUGO,            \
1819                         show_priv_session_##field,                      \
1820                         store_priv_session_##field)
1821 iscsi_priv_session_rw_attr(recovery_tmo, "%d");
1822
1823 /*
1824  * iSCSI host attrs
1825  */
1826 #define iscsi_host_attr_show(param)                                     \
1827 static ssize_t                                                          \
1828 show_host_param_##param(struct device *dev,                             \
1829                         struct device_attribute *attr, char *buf)       \
1830 {                                                                       \
1831         struct Scsi_Host *shost = transport_class_to_shost(dev);        \
1832         struct iscsi_internal *priv = to_iscsi_internal(shost->transportt); \
1833         return priv->iscsi_transport->get_host_param(shost, param, buf); \
1834 }
1835
1836 #define iscsi_host_attr(field, param)                                   \
1837         iscsi_host_attr_show(param)                                     \
1838 static ISCSI_CLASS_ATTR(host, field, S_IRUGO, show_host_param_##param,  \
1839                         NULL);
1840
1841 iscsi_host_attr(netdev, ISCSI_HOST_PARAM_NETDEV_NAME);
1842 iscsi_host_attr(hwaddress, ISCSI_HOST_PARAM_HWADDRESS);
1843 iscsi_host_attr(ipaddress, ISCSI_HOST_PARAM_IPADDRESS);
1844 iscsi_host_attr(initiatorname, ISCSI_HOST_PARAM_INITIATOR_NAME);
1845
1846 #define SETUP_PRIV_SESSION_RD_ATTR(field)                               \
1847 do {                                                                    \
1848         priv->session_attrs[count] = &dev_attr_priv_sess_##field; \
1849         count++;                                                        \
1850 } while (0)
1851
1852 #define SETUP_PRIV_SESSION_RW_ATTR(field)                               \
1853 do {                                                                    \
1854         priv->session_attrs[count] = &dev_attr_priv_sess_##field;       \
1855         count++;                                                        \
1856 } while (0)
1857
1858 #define SETUP_SESSION_RD_ATTR(field, param_flag)                        \
1859 do {                                                                    \
1860         if (tt->param_mask & param_flag) {                              \
1861                 priv->session_attrs[count] = &dev_attr_sess_##field; \
1862                 count++;                                                \
1863         }                                                               \
1864 } while (0)
1865
1866 #define SETUP_CONN_RD_ATTR(field, param_flag)                           \
1867 do {                                                                    \
1868         if (tt->param_mask & param_flag) {                              \
1869                 priv->conn_attrs[count] = &dev_attr_conn_##field; \
1870                 count++;                                                \
1871         }                                                               \
1872 } while (0)
1873
1874 #define SETUP_HOST_RD_ATTR(field, param_flag)                           \
1875 do {                                                                    \
1876         if (tt->host_param_mask & param_flag) {                         \
1877                 priv->host_attrs[count] = &dev_attr_host_##field; \
1878                 count++;                                                \
1879         }                                                               \
1880 } while (0)
1881
1882 static int iscsi_session_match(struct attribute_container *cont,
1883                            struct device *dev)
1884 {
1885         struct iscsi_cls_session *session;
1886         struct Scsi_Host *shost;
1887         struct iscsi_internal *priv;
1888
1889         if (!iscsi_is_session_dev(dev))
1890                 return 0;
1891
1892         session = iscsi_dev_to_session(dev);
1893         shost = iscsi_session_to_shost(session);
1894         if (!shost->transportt)
1895                 return 0;
1896
1897         priv = to_iscsi_internal(shost->transportt);
1898         if (priv->session_cont.ac.class != &iscsi_session_class.class)
1899                 return 0;
1900
1901         return &priv->session_cont.ac == cont;
1902 }
1903
1904 static int iscsi_conn_match(struct attribute_container *cont,
1905                            struct device *dev)
1906 {
1907         struct iscsi_cls_session *session;
1908         struct iscsi_cls_conn *conn;
1909         struct Scsi_Host *shost;
1910         struct iscsi_internal *priv;
1911
1912         if (!iscsi_is_conn_dev(dev))
1913                 return 0;
1914
1915         conn = iscsi_dev_to_conn(dev);
1916         session = iscsi_dev_to_session(conn->dev.parent);
1917         shost = iscsi_session_to_shost(session);
1918
1919         if (!shost->transportt)
1920                 return 0;
1921
1922         priv = to_iscsi_internal(shost->transportt);
1923         if (priv->conn_cont.ac.class != &iscsi_connection_class.class)
1924                 return 0;
1925
1926         return &priv->conn_cont.ac == cont;
1927 }
1928
1929 static int iscsi_host_match(struct attribute_container *cont,
1930                             struct device *dev)
1931 {
1932         struct Scsi_Host *shost;
1933         struct iscsi_internal *priv;
1934
1935         if (!scsi_is_host_device(dev))
1936                 return 0;
1937
1938         shost = dev_to_shost(dev);
1939         if (!shost->transportt  ||
1940             shost->transportt->host_attrs.ac.class != &iscsi_host_class.class)
1941                 return 0;
1942
1943         priv = to_iscsi_internal(shost->transportt);
1944         return &priv->t.host_attrs.ac == cont;
1945 }
1946
1947 struct scsi_transport_template *
1948 iscsi_register_transport(struct iscsi_transport *tt)
1949 {
1950         struct iscsi_internal *priv;
1951         unsigned long flags;
1952         int count = 0, err;
1953
1954         BUG_ON(!tt);
1955
1956         priv = iscsi_if_transport_lookup(tt);
1957         if (priv)
1958                 return NULL;
1959
1960         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1961         if (!priv)
1962                 return NULL;
1963         INIT_LIST_HEAD(&priv->list);
1964         priv->iscsi_transport = tt;
1965         priv->t.user_scan = iscsi_user_scan;
1966         priv->t.create_work_queue = 1;
1967
1968         priv->dev.class = &iscsi_transport_class;
1969         dev_set_name(&priv->dev, "%s", tt->name);
1970         err = device_register(&priv->dev);
1971         if (err)
1972                 goto free_priv;
1973
1974         err = sysfs_create_group(&priv->dev.kobj, &iscsi_transport_group);
1975         if (err)
1976                 goto unregister_dev;
1977
1978         /* host parameters */
1979         priv->t.host_attrs.ac.attrs = &priv->host_attrs[0];
1980         priv->t.host_attrs.ac.class = &iscsi_host_class.class;
1981         priv->t.host_attrs.ac.match = iscsi_host_match;
1982         priv->t.host_size = sizeof(struct iscsi_cls_host);
1983         transport_container_register(&priv->t.host_attrs);
1984
1985         SETUP_HOST_RD_ATTR(netdev, ISCSI_HOST_NETDEV_NAME);
1986         SETUP_HOST_RD_ATTR(ipaddress, ISCSI_HOST_IPADDRESS);
1987         SETUP_HOST_RD_ATTR(hwaddress, ISCSI_HOST_HWADDRESS);
1988         SETUP_HOST_RD_ATTR(initiatorname, ISCSI_HOST_INITIATOR_NAME);
1989         BUG_ON(count > ISCSI_HOST_ATTRS);
1990         priv->host_attrs[count] = NULL;
1991         count = 0;
1992
1993         /* connection parameters */
1994         priv->conn_cont.ac.attrs = &priv->conn_attrs[0];
1995         priv->conn_cont.ac.class = &iscsi_connection_class.class;
1996         priv->conn_cont.ac.match = iscsi_conn_match;
1997         transport_container_register(&priv->conn_cont);
1998
1999         SETUP_CONN_RD_ATTR(max_recv_dlength, ISCSI_MAX_RECV_DLENGTH);
2000         SETUP_CONN_RD_ATTR(max_xmit_dlength, ISCSI_MAX_XMIT_DLENGTH);
2001         SETUP_CONN_RD_ATTR(header_digest, ISCSI_HDRDGST_EN);
2002         SETUP_CONN_RD_ATTR(data_digest, ISCSI_DATADGST_EN);
2003         SETUP_CONN_RD_ATTR(ifmarker, ISCSI_IFMARKER_EN);
2004         SETUP_CONN_RD_ATTR(ofmarker, ISCSI_OFMARKER_EN);
2005         SETUP_CONN_RD_ATTR(address, ISCSI_CONN_ADDRESS);
2006         SETUP_CONN_RD_ATTR(port, ISCSI_CONN_PORT);
2007         SETUP_CONN_RD_ATTR(exp_statsn, ISCSI_EXP_STATSN);
2008         SETUP_CONN_RD_ATTR(persistent_address, ISCSI_PERSISTENT_ADDRESS);
2009         SETUP_CONN_RD_ATTR(persistent_port, ISCSI_PERSISTENT_PORT);
2010         SETUP_CONN_RD_ATTR(ping_tmo, ISCSI_PING_TMO);
2011         SETUP_CONN_RD_ATTR(recv_tmo, ISCSI_RECV_TMO);
2012
2013         BUG_ON(count > ISCSI_CONN_ATTRS);
2014         priv->conn_attrs[count] = NULL;
2015         count = 0;
2016
2017         /* session parameters */
2018         priv->session_cont.ac.attrs = &priv->session_attrs[0];
2019         priv->session_cont.ac.class = &iscsi_session_class.class;
2020         priv->session_cont.ac.match = iscsi_session_match;
2021         transport_container_register(&priv->session_cont);
2022
2023         SETUP_SESSION_RD_ATTR(initial_r2t, ISCSI_INITIAL_R2T_EN);
2024         SETUP_SESSION_RD_ATTR(max_outstanding_r2t, ISCSI_MAX_R2T);
2025         SETUP_SESSION_RD_ATTR(immediate_data, ISCSI_IMM_DATA_EN);
2026         SETUP_SESSION_RD_ATTR(first_burst_len, ISCSI_FIRST_BURST);
2027         SETUP_SESSION_RD_ATTR(max_burst_len, ISCSI_MAX_BURST);
2028         SETUP_SESSION_RD_ATTR(data_pdu_in_order, ISCSI_PDU_INORDER_EN);
2029         SETUP_SESSION_RD_ATTR(data_seq_in_order, ISCSI_DATASEQ_INORDER_EN);
2030         SETUP_SESSION_RD_ATTR(erl, ISCSI_ERL);
2031         SETUP_SESSION_RD_ATTR(targetname, ISCSI_TARGET_NAME);
2032         SETUP_SESSION_RD_ATTR(tpgt, ISCSI_TPGT);
2033         SETUP_SESSION_RD_ATTR(password, ISCSI_USERNAME);
2034         SETUP_SESSION_RD_ATTR(password_in, ISCSI_USERNAME_IN);
2035         SETUP_SESSION_RD_ATTR(username, ISCSI_PASSWORD);
2036         SETUP_SESSION_RD_ATTR(username_in, ISCSI_PASSWORD_IN);
2037         SETUP_SESSION_RD_ATTR(fast_abort, ISCSI_FAST_ABORT);
2038         SETUP_SESSION_RD_ATTR(abort_tmo, ISCSI_ABORT_TMO);
2039         SETUP_SESSION_RD_ATTR(lu_reset_tmo,ISCSI_LU_RESET_TMO);
2040         SETUP_SESSION_RD_ATTR(tgt_reset_tmo,ISCSI_TGT_RESET_TMO);
2041         SETUP_SESSION_RD_ATTR(ifacename, ISCSI_IFACE_NAME);
2042         SETUP_SESSION_RD_ATTR(initiatorname, ISCSI_INITIATOR_NAME);
2043         SETUP_SESSION_RD_ATTR(targetalias, ISCSI_TARGET_ALIAS);
2044         SETUP_PRIV_SESSION_RW_ATTR(recovery_tmo);
2045         SETUP_PRIV_SESSION_RD_ATTR(state);
2046
2047         BUG_ON(count > ISCSI_SESSION_ATTRS);
2048         priv->session_attrs[count] = NULL;
2049
2050         spin_lock_irqsave(&iscsi_transport_lock, flags);
2051         list_add(&priv->list, &iscsi_transports);
2052         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
2053
2054         printk(KERN_NOTICE "iscsi: registered transport (%s)\n", tt->name);
2055         return &priv->t;
2056
2057 unregister_dev:
2058         device_unregister(&priv->dev);
2059         return NULL;
2060 free_priv:
2061         kfree(priv);
2062         return NULL;
2063 }
2064 EXPORT_SYMBOL_GPL(iscsi_register_transport);
2065
2066 int iscsi_unregister_transport(struct iscsi_transport *tt)
2067 {
2068         struct iscsi_internal *priv;
2069         unsigned long flags;
2070
2071         BUG_ON(!tt);
2072
2073         mutex_lock(&rx_queue_mutex);
2074
2075         priv = iscsi_if_transport_lookup(tt);
2076         BUG_ON (!priv);
2077
2078         spin_lock_irqsave(&iscsi_transport_lock, flags);
2079         list_del(&priv->list);
2080         spin_unlock_irqrestore(&iscsi_transport_lock, flags);
2081
2082         transport_container_unregister(&priv->conn_cont);
2083         transport_container_unregister(&priv->session_cont);
2084         transport_container_unregister(&priv->t.host_attrs);
2085
2086         sysfs_remove_group(&priv->dev.kobj, &iscsi_transport_group);
2087         device_unregister(&priv->dev);
2088         mutex_unlock(&rx_queue_mutex);
2089
2090         return 0;
2091 }
2092 EXPORT_SYMBOL_GPL(iscsi_unregister_transport);
2093
2094 static __init int iscsi_transport_init(void)
2095 {
2096         int err;
2097
2098         printk(KERN_INFO "Loading iSCSI transport class v%s.\n",
2099                 ISCSI_TRANSPORT_VERSION);
2100
2101         atomic_set(&iscsi_session_nr, 0);
2102
2103         err = class_register(&iscsi_transport_class);
2104         if (err)
2105                 return err;
2106
2107         err = class_register(&iscsi_endpoint_class);
2108         if (err)
2109                 goto unregister_transport_class;
2110
2111         err = transport_class_register(&iscsi_host_class);
2112         if (err)
2113                 goto unregister_endpoint_class;
2114
2115         err = transport_class_register(&iscsi_connection_class);
2116         if (err)
2117                 goto unregister_host_class;
2118
2119         err = transport_class_register(&iscsi_session_class);
2120         if (err)
2121                 goto unregister_conn_class;
2122
2123         nls = netlink_kernel_create(&init_net, NETLINK_ISCSI, 1, iscsi_if_rx,
2124                                     NULL, THIS_MODULE);
2125         if (!nls) {
2126                 err = -ENOBUFS;
2127                 goto unregister_session_class;
2128         }
2129
2130         iscsi_eh_timer_workq = create_singlethread_workqueue("iscsi_eh");
2131         if (!iscsi_eh_timer_workq)
2132                 goto release_nls;
2133
2134         return 0;
2135
2136 release_nls:
2137         netlink_kernel_release(nls);
2138 unregister_session_class:
2139         transport_class_unregister(&iscsi_session_class);
2140 unregister_conn_class:
2141         transport_class_unregister(&iscsi_connection_class);
2142 unregister_host_class:
2143         transport_class_unregister(&iscsi_host_class);
2144 unregister_endpoint_class:
2145         class_unregister(&iscsi_endpoint_class);
2146 unregister_transport_class:
2147         class_unregister(&iscsi_transport_class);
2148         return err;
2149 }
2150
2151 static void __exit iscsi_transport_exit(void)
2152 {
2153         destroy_workqueue(iscsi_eh_timer_workq);
2154         netlink_kernel_release(nls);
2155         transport_class_unregister(&iscsi_connection_class);
2156         transport_class_unregister(&iscsi_session_class);
2157         transport_class_unregister(&iscsi_host_class);
2158         class_unregister(&iscsi_endpoint_class);
2159         class_unregister(&iscsi_transport_class);
2160 }
2161
2162 module_init(iscsi_transport_init);
2163 module_exit(iscsi_transport_exit);
2164
2165 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
2166               "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
2167               "Alex Aizman <itn780@yahoo.com>");
2168 MODULE_DESCRIPTION("iSCSI Transport Interface");
2169 MODULE_LICENSE("GPL");
2170 MODULE_VERSION(ISCSI_TRANSPORT_VERSION);