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);
1983