[SCSI] sym2: Use DMA_40BIT_MASK constant
[linux-2.6/openmoko-kernel/knife-kernel.git] / drivers / scsi / scsi_transport_iscsi.c
blob49fd18c1a9c6d2d4daa433fd8b5ef15ff0ff8ae6
1 /*
2 * iSCSI transport class definitions
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
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.
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.
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.
23 #include <linux/module.h>
24 #include <linux/string.h>
25 #include <linux/slab.h>
26 #include <linux/mempool.h>
27 #include <net/tcp.h>
29 #include <scsi/scsi.h>
30 #include <scsi/scsi_host.h>
31 #include <scsi/scsi_device.h>
32 #include <scsi/scsi_transport.h>
33 #include <scsi/scsi_transport_iscsi.h>
34 #include <scsi/iscsi_if.h>
36 #define ISCSI_SESSION_ATTRS 8
37 #define ISCSI_CONN_ATTRS 6
39 struct iscsi_internal {
40 struct scsi_transport_template t;
41 struct iscsi_transport *iscsi_transport;
42 struct list_head list;
44 * List of sessions for this transport
46 struct list_head sessions;
48 * lock to serialize access to the sessions list which must
49 * be taken after the rx_queue_sema
51 spinlock_t session_lock;
53 * based on transport capabilities, at register time we set these
54 * bits to tell the transport class it wants attributes displayed
55 * in sysfs or that it can support different iSCSI Data-Path
56 * capabilities
58 uint32_t param_mask;
60 struct class_device cdev;
62 * We do not have any private or other attrs.
64 struct transport_container conn_cont;
65 struct class_device_attribute *conn_attrs[ISCSI_CONN_ATTRS + 1];
66 struct transport_container session_cont;
67 struct class_device_attribute *session_attrs[ISCSI_SESSION_ATTRS + 1];
71 * list of registered transports and lock that must
72 * be held while accessing list. The iscsi_transport_lock must
73 * be acquired after the rx_queue_sema.
75 static LIST_HEAD(iscsi_transports);
76 static DEFINE_SPINLOCK(iscsi_transport_lock);
78 #define to_iscsi_internal(tmpl) \
79 container_of(tmpl, struct iscsi_internal, t)
81 #define cdev_to_iscsi_internal(_cdev) \
82 container_of(_cdev, struct iscsi_internal, cdev)
84 static void iscsi_transport_release(struct class_device *cdev)
86 struct iscsi_internal *priv = cdev_to_iscsi_internal(cdev);
87 kfree(priv);
91 * iscsi_transport_class represents the iscsi_transports that are
92 * registered.
94 static struct class iscsi_transport_class = {
95 .name = "iscsi_transport",
96 .release = iscsi_transport_release,
99 static ssize_t
100 show_transport_handle(struct class_device *cdev, char *buf)
102 struct iscsi_internal *priv = cdev_to_iscsi_internal(cdev);
103 return sprintf(buf, "%llu\n", (unsigned long long)iscsi_handle(priv->iscsi_transport));
105 static CLASS_DEVICE_ATTR(handle, S_IRUGO, show_transport_handle, NULL);
107 #define show_transport_attr(name, format) \
108 static ssize_t \
109 show_transport_##name(struct class_device *cdev, char *buf) \
111 struct iscsi_internal *priv = cdev_to_iscsi_internal(cdev); \
112 return sprintf(buf, format"\n", priv->iscsi_transport->name); \
114 static CLASS_DEVICE_ATTR(name, S_IRUGO, show_transport_##name, NULL);
116 show_transport_attr(caps, "0x%x");
117 show_transport_attr(max_lun, "%d");
118 show_transport_attr(max_conn, "%d");
119 show_transport_attr(max_cmd_len, "%d");
121 static struct attribute *iscsi_transport_attrs[] = {
122 &class_device_attr_handle.attr,
123 &class_device_attr_caps.attr,
124 &class_device_attr_max_lun.attr,
125 &class_device_attr_max_conn.attr,
126 &class_device_attr_max_cmd_len.attr,
127 NULL,
130 static struct attribute_group iscsi_transport_group = {
131 .attrs = iscsi_transport_attrs,
134 static DECLARE_TRANSPORT_CLASS(iscsi_session_class,
135 "iscsi_session",
136 NULL,
137 NULL,
138 NULL);
140 static DECLARE_TRANSPORT_CLASS(iscsi_connection_class,
141 "iscsi_connection",
142 NULL,
143 NULL,
144 NULL);
146 static struct sock *nls;
147 static int daemon_pid;
148 static DECLARE_MUTEX(rx_queue_sema);
150 struct mempool_zone {
151 mempool_t *pool;
152 atomic_t allocated;
153 int size;
154 int hiwat;
155 struct list_head freequeue;
156 spinlock_t freelock;
159 static struct mempool_zone z_reply;
162 * Z_MAX_* - actual mempool size allocated at the mempool_zone_init() time
163 * Z_HIWAT_* - zone's high watermark when if_error bit will be set to -ENOMEM
164 * so daemon will notice OOM on NETLINK tranposrt level and will
165 * be able to predict or change operational behavior
167 #define Z_MAX_REPLY 8
168 #define Z_HIWAT_REPLY 6
169 #define Z_MAX_PDU 8
170 #define Z_HIWAT_PDU 6
171 #define Z_MAX_ERROR 16
172 #define Z_HIWAT_ERROR 12
174 struct iscsi_if_conn {
175 struct list_head conn_list; /* item in connlist */
176 struct list_head session_list; /* item in session->connections */
177 iscsi_connh_t connh;
178 int active; /* must be accessed with the connlock */
179 struct Scsi_Host *host; /* originated shost */
180 struct device dev; /* sysfs transport/container device */
181 struct iscsi_transport *transport;
182 struct mempool_zone z_error;
183 struct mempool_zone z_pdu;
184 struct list_head freequeue;
187 #define iscsi_dev_to_if_conn(_dev) \
188 container_of(_dev, struct iscsi_if_conn, dev)
190 #define iscsi_cdev_to_if_conn(_cdev) \
191 iscsi_dev_to_if_conn(_cdev->dev)
193 static LIST_HEAD(connlist);
194 static DEFINE_SPINLOCK(connlock);
196 struct iscsi_if_session {
197 struct list_head list; /* item in session_list */
198 struct list_head connections;
199 iscsi_sessionh_t sessionh;
200 struct iscsi_transport *transport;
201 struct device dev; /* sysfs transport/container device */
204 #define iscsi_dev_to_if_session(_dev) \
205 container_of(_dev, struct iscsi_if_session, dev)
207 #define iscsi_cdev_to_if_session(_cdev) \
208 iscsi_dev_to_if_session(_cdev->dev)
210 #define iscsi_if_session_to_shost(_session) \
211 dev_to_shost(_session->dev.parent)
213 static struct iscsi_if_conn*
214 iscsi_if_find_conn(uint64_t key)
216 unsigned long flags;
217 struct iscsi_if_conn *conn;
219 spin_lock_irqsave(&connlock, flags);
220 list_for_each_entry(conn, &connlist, conn_list)
221 if (conn->connh == key) {
222 spin_unlock_irqrestore(&connlock, flags);
223 return conn;
225 spin_unlock_irqrestore(&connlock, flags);
226 return NULL;
229 static struct iscsi_internal *
230 iscsi_if_transport_lookup(struct iscsi_transport *tt)
232 struct iscsi_internal *priv;
233 unsigned long flags;
235 spin_lock_irqsave(&iscsi_transport_lock, flags);
236 list_for_each_entry(priv, &iscsi_transports, list) {
237 if (tt == priv->iscsi_transport) {
238 spin_unlock_irqrestore(&iscsi_transport_lock, flags);
239 return priv;
242 spin_unlock_irqrestore(&iscsi_transport_lock, flags);
243 return NULL;
246 static inline struct list_head *skb_to_lh(struct sk_buff *skb)
248 return (struct list_head *)&skb->cb;
251 static void*
252 mempool_zone_alloc_skb(unsigned int gfp_mask, void *pool_data)
254 struct mempool_zone *zone = pool_data;
256 return alloc_skb(zone->size, gfp_mask);
259 static void
260 mempool_zone_free_skb(void *element, void *pool_data)
262 kfree_skb(element);
265 static void
266 mempool_zone_complete(struct mempool_zone *zone)
268 unsigned long flags;
269 struct list_head *lh, *n;
271 spin_lock_irqsave(&zone->freelock, flags);
272 list_for_each_safe(lh, n, &zone->freequeue) {
273 struct sk_buff *skb = (struct sk_buff *)((char *)lh -
274 offsetof(struct sk_buff, cb));
275 if (!skb_shared(skb)) {
276 list_del(skb_to_lh(skb));
277 mempool_free(skb, zone->pool);
278 atomic_dec(&zone->allocated);
281 spin_unlock_irqrestore(&zone->freelock, flags);
284 static int
285 mempool_zone_init(struct mempool_zone *zp, unsigned max, unsigned size,
286 unsigned hiwat)
288 zp->pool = mempool_create(max, mempool_zone_alloc_skb,
289 mempool_zone_free_skb, zp);
290 if (!zp->pool)
291 return -ENOMEM;
293 zp->size = size;
294 zp->hiwat = hiwat;
296 INIT_LIST_HEAD(&zp->freequeue);
297 spin_lock_init(&zp->freelock);
298 atomic_set(&zp->allocated, 0);
300 return 0;
304 static struct sk_buff*
305 mempool_zone_get_skb(struct mempool_zone *zone)
307 struct sk_buff *skb;
309 skb = mempool_alloc(zone->pool, GFP_ATOMIC);
310 if (skb)
311 atomic_inc(&zone->allocated);
312 return skb;
315 static int
316 iscsi_unicast_skb(struct mempool_zone *zone, struct sk_buff *skb)
318 unsigned long flags;
319 int rc;
321 skb_get(skb);
322 rc = netlink_unicast(nls, skb, daemon_pid, MSG_DONTWAIT);
323 if (rc < 0) {
324 mempool_free(skb, zone->pool);
325 printk(KERN_ERR "iscsi: can not unicast skb (%d)\n", rc);
326 return rc;
329 spin_lock_irqsave(&zone->freelock, flags);
330 list_add(skb_to_lh(skb), &zone->freequeue);
331 spin_unlock_irqrestore(&zone->freelock, flags);
333 return 0;
336 int iscsi_recv_pdu(iscsi_connh_t connh, struct iscsi_hdr *hdr,
337 char *data, uint32_t data_size)
339 struct nlmsghdr *nlh;
340 struct sk_buff *skb;
341 struct iscsi_uevent *ev;
342 struct iscsi_if_conn *conn;
343 char *pdu;
344 int len = NLMSG_SPACE(sizeof(*ev) + sizeof(struct iscsi_hdr) +
345 data_size);
347 conn = iscsi_if_find_conn(connh);
348 BUG_ON(!conn);
350 mempool_zone_complete(&conn->z_pdu);
352 skb = mempool_zone_get_skb(&conn->z_pdu);
353 if (!skb) {
354 iscsi_conn_error(connh, ISCSI_ERR_CONN_FAILED);
355 printk(KERN_ERR "iscsi%d: can not deliver control PDU: OOM\n",
356 conn->host->host_no);
357 return -ENOMEM;
360 nlh = __nlmsg_put(skb, daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
361 ev = NLMSG_DATA(nlh);
362 memset(ev, 0, sizeof(*ev));
363 ev->transport_handle = iscsi_handle(conn->transport);
364 ev->type = ISCSI_KEVENT_RECV_PDU;
365 if (atomic_read(&conn->z_pdu.allocated) >= conn->z_pdu.hiwat)
366 ev->iferror = -ENOMEM;
367 ev->r.recv_req.conn_handle = connh;
368 pdu = (char*)ev + sizeof(*ev);
369 memcpy(pdu, hdr, sizeof(struct iscsi_hdr));
370 memcpy(pdu + sizeof(struct iscsi_hdr), data, data_size);
372 return iscsi_unicast_skb(&conn->z_pdu, skb);
374 EXPORT_SYMBOL_GPL(iscsi_recv_pdu);
376 void iscsi_conn_error(iscsi_connh_t connh, enum iscsi_err error)
378 struct nlmsghdr *nlh;
379 struct sk_buff *skb;
380 struct iscsi_uevent *ev;
381 struct iscsi_if_conn *conn;
382 int len = NLMSG_SPACE(sizeof(*ev));
384 conn = iscsi_if_find_conn(connh);
385 BUG_ON(!conn);
387 mempool_zone_complete(&conn->z_error);
389 skb = mempool_zone_get_skb(&conn->z_error);
390 if (!skb) {
391 printk(KERN_ERR "iscsi%d: gracefully ignored conn error (%d)\n",
392 conn->host->host_no, error);
393 return;
396 nlh = __nlmsg_put(skb, daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
397 ev = NLMSG_DATA(nlh);
398 ev->transport_handle = iscsi_handle(conn->transport);
399 ev->type = ISCSI_KEVENT_CONN_ERROR;
400 if (atomic_read(&conn->z_error.allocated) >= conn->z_error.hiwat)
401 ev->iferror = -ENOMEM;
402 ev->r.connerror.error = error;
403 ev->r.connerror.conn_handle = connh;
405 iscsi_unicast_skb(&conn->z_error, skb);
407 printk(KERN_INFO "iscsi%d: detected conn error (%d)\n",
408 conn->host->host_no, error);
410 EXPORT_SYMBOL_GPL(iscsi_conn_error);
412 static int
413 iscsi_if_send_reply(int pid, int seq, int type, int done, int multi,
414 void *payload, int size)
416 struct sk_buff *skb;
417 struct nlmsghdr *nlh;
418 int len = NLMSG_SPACE(size);
419 int flags = multi ? NLM_F_MULTI : 0;
420 int t = done ? NLMSG_DONE : type;
422 mempool_zone_complete(&z_reply);
424 skb = mempool_zone_get_skb(&z_reply);
426 * FIXME:
427 * user is supposed to react on iferror == -ENOMEM;
428 * see iscsi_if_rx().
430 BUG_ON(!skb);
432 nlh = __nlmsg_put(skb, pid, seq, t, (len - sizeof(*nlh)), 0);
433 nlh->nlmsg_flags = flags;
434 memcpy(NLMSG_DATA(nlh), payload, size);
435 return iscsi_unicast_skb(&z_reply, skb);
439 * iSCSI Session's hostdata organization:
441 * *------------------* <== host->hostdata
442 * | transport |
443 * |------------------| <== iscsi_hostdata(host->hostdata)
444 * | transport's data |
445 * |------------------| <== hostdata_session(host->hostdata)
446 * | interface's data |
447 * *------------------*
450 #define hostdata_privsize(_t) (sizeof(unsigned long) + _t->hostdata_size + \
451 _t->hostdata_size % sizeof(unsigned long) + \
452 sizeof(struct iscsi_if_session))
454 #define hostdata_session(_hostdata) ((void*)_hostdata + sizeof(unsigned long) + \
455 ((struct iscsi_transport *) \
456 iscsi_ptr(*(uint64_t *)_hostdata))->hostdata_size)
458 static void iscsi_if_session_dev_release(struct device *dev)
460 struct iscsi_if_session *session = iscsi_dev_to_if_session(dev);
461 struct iscsi_transport *transport = session->transport;
462 struct Scsi_Host *shost = iscsi_if_session_to_shost(session);
463 struct iscsi_if_conn *conn, *tmp;
464 unsigned long flags;
466 /* now free connections */
467 spin_lock_irqsave(&connlock, flags);
468 list_for_each_entry_safe(conn, tmp, &session->connections,
469 session_list) {
470 list_del(&conn->session_list);
471 mempool_destroy(conn->z_pdu.pool);
472 mempool_destroy(conn->z_error.pool);
473 kfree(conn);
475 spin_unlock_irqrestore(&connlock, flags);
476 scsi_host_put(shost);
477 module_put(transport->owner);
480 static int
481 iscsi_if_create_session(struct iscsi_internal *priv, struct iscsi_uevent *ev)
483 struct iscsi_transport *transport = priv->iscsi_transport;
484 struct iscsi_if_session *session;
485 struct Scsi_Host *shost;
486 unsigned long flags;
487 int error;
489 if (!try_module_get(transport->owner))
490 return -EPERM;
492 shost = scsi_host_alloc(transport->host_template,
493 hostdata_privsize(transport));
494 if (!shost) {
495 ev->r.c_session_ret.session_handle = iscsi_handle(NULL);
496 printk(KERN_ERR "iscsi: can not allocate SCSI host for "
497 "session\n");
498 error = -ENOMEM;
499 goto out_module_put;
501 shost->max_id = 1;
502 shost->max_channel = 0;
503 shost->max_lun = transport->max_lun;
504 shost->max_cmd_len = transport->max_cmd_len;
505 shost->transportt = &priv->t;
507 /* store struct iscsi_transport in hostdata */
508 *(uint64_t*)shost->hostdata = ev->transport_handle;
510 ev->r.c_session_ret.session_handle = transport->create_session(
511 ev->u.c_session.initial_cmdsn, shost);
512 if (ev->r.c_session_ret.session_handle == iscsi_handle(NULL)) {
513 error = 0;
514 goto out_host_put;
517 /* host_no becomes assigned SID */
518 ev->r.c_session_ret.sid = shost->host_no;
519 /* initialize session */
520 session = hostdata_session(shost->hostdata);
521 INIT_LIST_HEAD(&session->connections);
522 INIT_LIST_HEAD(&session->list);
523 session->sessionh = ev->r.c_session_ret.session_handle;
524 session->transport = transport;
526 error = scsi_add_host(shost, NULL);
527 if (error)
528 goto out_destroy_session;
531 * this is released in the dev's release function)
533 scsi_host_get(shost);
534 snprintf(session->dev.bus_id, BUS_ID_SIZE, "session%u", shost->host_no);
535 session->dev.parent = &shost->shost_gendev;
536 session->dev.release = iscsi_if_session_dev_release;
537 error = device_register(&session->dev);
538 if (error) {
539 printk(KERN_ERR "iscsi: could not register session%d's dev\n",
540 shost->host_no);
541 goto out_remove_host;
543 transport_register_device(&session->dev);
545 /* add this session to the list of active sessions */
546 spin_lock_irqsave(&priv->session_lock, flags);
547 list_add(&session->list, &priv->sessions);
548 spin_unlock_irqrestore(&priv->session_lock, flags);
550 return 0;
552 out_remove_host:
553 scsi_remove_host(shost);
554 out_destroy_session:
555 transport->destroy_session(ev->r.c_session_ret.session_handle);
556 ev->r.c_session_ret.session_handle = iscsi_handle(NULL);
557 out_host_put:
558 scsi_host_put(shost);
559 out_module_put:
560 module_put(transport->owner);
561 return error;
564 static int
565 iscsi_if_destroy_session(struct iscsi_internal *priv, struct iscsi_uevent *ev)
567 struct iscsi_transport *transport = priv->iscsi_transport;
568 struct Scsi_Host *shost;
569 struct iscsi_if_session *session;
570 unsigned long flags;
571 struct iscsi_if_conn *conn;
572 int error = 0;
574 shost = scsi_host_lookup(ev->u.d_session.sid);
575 if (shost == ERR_PTR(-ENXIO))
576 return -EEXIST;
577 session = hostdata_session(shost->hostdata);
579 /* check if we have active connections */
580 spin_lock_irqsave(&connlock, flags);
581 list_for_each_entry(conn, &session->connections, session_list) {
582 if (conn->active) {
583 printk(KERN_ERR "iscsi%d: can not destroy session: "
584 "has active connection (%p)\n",
585 shost->host_no, iscsi_ptr(conn->connh));
586 spin_unlock_irqrestore(&connlock, flags);
587 error = EIO;
588 goto out_release_ref;
591 spin_unlock_irqrestore(&connlock, flags);
593 scsi_remove_host(shost);
594 transport->destroy_session(ev->u.d_session.session_handle);
595 transport_unregister_device(&session->dev);
596 device_unregister(&session->dev);
598 /* remove this session from the list of active sessions */
599 spin_lock_irqsave(&priv->session_lock, flags);
600 list_del(&session->list);
601 spin_unlock_irqrestore(&priv->session_lock, flags);
603 /* ref from host alloc */
604 scsi_host_put(shost);
605 out_release_ref:
606 /* ref from host lookup */
607 scsi_host_put(shost);
608 return error;
611 static void iscsi_if_conn_dev_release(struct device *dev)
613 struct iscsi_if_conn *conn = iscsi_dev_to_if_conn(dev);
614 struct Scsi_Host *shost = conn->host;
616 scsi_host_put(shost);
619 static int
620 iscsi_if_create_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
622 struct iscsi_if_session *session;
623 struct Scsi_Host *shost;
624 struct iscsi_if_conn *conn;
625 unsigned long flags;
626 int error;
628 shost = scsi_host_lookup(ev->u.c_conn.sid);
629 if (shost == ERR_PTR(-ENXIO))
630 return -EEXIST;
631 session = hostdata_session(shost->hostdata);
633 conn = kmalloc(sizeof(struct iscsi_if_conn), GFP_KERNEL);
634 if (!conn) {
635 error = -ENOMEM;
636 goto out_release_ref;
638 memset(conn, 0, sizeof(struct iscsi_if_conn));
639 INIT_LIST_HEAD(&conn->session_list);
640 INIT_LIST_HEAD(&conn->conn_list);
641 conn->host = shost;
642 conn->transport = transport;
644 error = mempool_zone_init(&conn->z_pdu, Z_MAX_PDU,
645 NLMSG_SPACE(sizeof(struct iscsi_uevent) +
646 sizeof(struct iscsi_hdr) +
647 DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH),
648 Z_HIWAT_PDU);
649 if (error) {
650 printk(KERN_ERR "iscsi%d: can not allocate pdu zone for new "
651 "conn\n", shost->host_no);
652 goto out_free_conn;
654 error = mempool_zone_init(&conn->z_error, Z_MAX_ERROR,
655 NLMSG_SPACE(sizeof(struct iscsi_uevent)),
656 Z_HIWAT_ERROR);
657 if (error) {
658 printk(KERN_ERR "iscsi%d: can not allocate error zone for "
659 "new conn\n", shost->host_no);
660 goto out_free_pdu_pool;
663 ev->r.handle = transport->create_conn(ev->u.c_conn.session_handle,
664 ev->u.c_conn.cid);
665 if (!ev->r.handle) {
666 error = -ENODEV;
667 goto out_free_error_pool;
670 conn->connh = ev->r.handle;
673 * this is released in the dev's release function
675 if (!scsi_host_get(shost))
676 goto out_destroy_conn;
677 snprintf(conn->dev.bus_id, BUS_ID_SIZE, "connection%d:%u",
678 shost->host_no, ev->u.c_conn.cid);
679 conn->dev.parent = &session->dev;
680 conn->dev.release = iscsi_if_conn_dev_release;
681 error = device_register(&conn->dev);
682 if (error) {
683 printk(KERN_ERR "iscsi%d: could not register connections%u "
684 "dev\n", shost->host_no, ev->u.c_conn.cid);
685 goto out_release_parent_ref;
687 transport_register_device(&conn->dev);
689 spin_lock_irqsave(&connlock, flags);
690 list_add(&conn->conn_list, &connlist);
691 list_add(&conn->session_list, &session->connections);
692 conn->active = 1;
693 spin_unlock_irqrestore(&connlock, flags);
695 scsi_host_put(shost);
696 return 0;
698 out_release_parent_ref:
699 scsi_host_put(shost);
700 out_destroy_conn:
701 transport->destroy_conn(ev->r.handle);
702 out_free_error_pool:
703 mempool_destroy(conn->z_error.pool);
704 out_free_pdu_pool:
705 mempool_destroy(conn->z_pdu.pool);
706 out_free_conn:
707 kfree(conn);
708 out_release_ref:
709 scsi_host_put(shost);
710 return error;
713 static int
714 iscsi_if_destroy_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
716 unsigned long flags;
717 struct iscsi_if_conn *conn;
719 conn = iscsi_if_find_conn(ev->u.d_conn.conn_handle);
720 if (!conn)
721 return -EEXIST;
723 transport->destroy_conn(ev->u.d_conn.conn_handle);
725 spin_lock_irqsave(&connlock, flags);
726 conn->active = 0;
727 list_del(&conn->conn_list);
728 spin_unlock_irqrestore(&connlock, flags);
730 transport_unregister_device(&conn->dev);
731 device_unregister(&conn->dev);
732 return 0;
735 static int
736 iscsi_if_get_stats(struct iscsi_transport *transport, struct sk_buff *skb,
737 struct nlmsghdr *nlh)
739 struct iscsi_uevent *ev = NLMSG_DATA(nlh);
740 struct iscsi_stats *stats;
741 struct sk_buff *skbstat;
742 struct iscsi_if_conn *conn;
743 struct nlmsghdr *nlhstat;
744 struct iscsi_uevent *evstat;
745 int len = NLMSG_SPACE(sizeof(*ev) +
746 sizeof(struct iscsi_stats) +
747 sizeof(struct iscsi_stats_custom) *
748 ISCSI_STATS_CUSTOM_MAX);
749 int err = 0;
751 conn = iscsi_if_find_conn(ev->u.get_stats.conn_handle);
752 if (!conn)
753 return -EEXIST;
755 do {
756 int actual_size;
758 mempool_zone_complete(&conn->z_pdu);
760 skbstat = mempool_zone_get_skb(&conn->z_pdu);
761 if (!skbstat) {
762 printk(KERN_ERR "iscsi%d: can not deliver stats: OOM\n",
763 conn->host->host_no);
764 return -ENOMEM;
767 nlhstat = __nlmsg_put(skbstat, daemon_pid, 0, 0,
768 (len - sizeof(*nlhstat)), 0);
769 evstat = NLMSG_DATA(nlhstat);
770 memset(evstat, 0, sizeof(*evstat));
771 evstat->transport_handle = iscsi_handle(conn->transport);
772 evstat->type = nlh->nlmsg_type;
773 if (atomic_read(&conn->z_pdu.allocated) >= conn->z_pdu.hiwat)
774 evstat->iferror = -ENOMEM;
775 evstat->u.get_stats.conn_handle =
776 ev->u.get_stats.conn_handle;
777 stats = (struct iscsi_stats *)
778 ((char*)evstat + sizeof(*evstat));
779 memset(stats, 0, sizeof(*stats));
781 transport->get_stats(ev->u.get_stats.conn_handle, stats);
782 actual_size = NLMSG_SPACE(sizeof(struct iscsi_uevent) +
783 sizeof(struct iscsi_stats) +
784 sizeof(struct iscsi_stats_custom) *
785 stats->custom_length);
786 actual_size -= sizeof(*nlhstat);
787 actual_size = NLMSG_LENGTH(actual_size);
788 skb_trim(skb, NLMSG_ALIGN(actual_size));
789 nlhstat->nlmsg_len = actual_size;
791 err = iscsi_unicast_skb(&conn->z_pdu, skbstat);
792 } while (err < 0 && err != -ECONNREFUSED);
794 return err;
797 static int
798 iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
800 int err = 0;
801 struct iscsi_uevent *ev = NLMSG_DATA(nlh);
802 struct iscsi_transport *transport = NULL;
803 struct iscsi_internal *priv;
805 if (NETLINK_CREDS(skb)->uid)
806 return -EPERM;
808 priv = iscsi_if_transport_lookup(iscsi_ptr(ev->transport_handle));
809 if (!priv)
810 return -EINVAL;
811 transport = priv->iscsi_transport;
813 daemon_pid = NETLINK_CREDS(skb)->pid;
815 switch (nlh->nlmsg_type) {
816 case ISCSI_UEVENT_CREATE_SESSION:
817 err = iscsi_if_create_session(priv, ev);
818 break;
819 case ISCSI_UEVENT_DESTROY_SESSION:
820 err = iscsi_if_destroy_session(priv, ev);
821 break;
822 case ISCSI_UEVENT_CREATE_CONN:
823 err = iscsi_if_create_conn(transport, ev);
824 break;
825 case ISCSI_UEVENT_DESTROY_CONN:
826 err = iscsi_if_destroy_conn(transport, ev);
827 break;
828 case ISCSI_UEVENT_BIND_CONN:
829 if (!iscsi_if_find_conn(ev->u.b_conn.conn_handle))
830 return -EEXIST;
831 ev->r.retcode = transport->bind_conn(
832 ev->u.b_conn.session_handle,
833 ev->u.b_conn.conn_handle,
834 ev->u.b_conn.transport_fd,
835 ev->u.b_conn.is_leading);
836 break;
837 case ISCSI_UEVENT_SET_PARAM:
838 if (!iscsi_if_find_conn(ev->u.set_param.conn_handle))
839 return -EEXIST;
840 ev->r.retcode = transport->set_param(
841 ev->u.set_param.conn_handle,
842 ev->u.set_param.param, ev->u.set_param.value);
843 break;
844 case ISCSI_UEVENT_START_CONN:
845 if (!iscsi_if_find_conn(ev->u.start_conn.conn_handle))
846 return -EEXIST;
847 ev->r.retcode = transport->start_conn(
848 ev->u.start_conn.conn_handle);
849 break;
850 case ISCSI_UEVENT_STOP_CONN:
851 if (!iscsi_if_find_conn(ev->u.stop_conn.conn_handle))
852 return -EEXIST;
853 transport->stop_conn(ev->u.stop_conn.conn_handle,
854 ev->u.stop_conn.flag);
855 break;
856 case ISCSI_UEVENT_SEND_PDU:
857 if (!iscsi_if_find_conn(ev->u.send_pdu.conn_handle))
858 return -EEXIST;
859 ev->r.retcode = transport->send_pdu(
860 ev->u.send_pdu.conn_handle,
861 (struct iscsi_hdr*)((char*)ev + sizeof(*ev)),
862 (char*)ev + sizeof(*ev) + ev->u.send_pdu.hdr_size,
863 ev->u.send_pdu.data_size);
864 break;
865 case ISCSI_UEVENT_GET_STATS:
866 err = iscsi_if_get_stats(transport, skb, nlh);
867 break;
868 default:
869 err = -EINVAL;
870 break;
873 return err;
876 /* Get message from skb (based on rtnetlink_rcv_skb). Each message is
877 * processed by iscsi_if_recv_msg. Malformed skbs with wrong length are
878 * discarded silently. */
879 static void
880 iscsi_if_rx(struct sock *sk, int len)
882 struct sk_buff *skb;
884 down(&rx_queue_sema);
885 while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
886 while (skb->len >= NLMSG_SPACE(0)) {
887 int err;
888 uint32_t rlen;
889 struct nlmsghdr *nlh;
890 struct iscsi_uevent *ev;
892 nlh = (struct nlmsghdr *)skb->data;
893 if (nlh->nlmsg_len < sizeof(*nlh) ||
894 skb->len < nlh->nlmsg_len) {
895 break;
897 ev = NLMSG_DATA(nlh);
898 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
899 if (rlen > skb->len)
900 rlen = skb->len;
901 err = iscsi_if_recv_msg(skb, nlh);
902 if (err) {
903 ev->type = ISCSI_KEVENT_IF_ERROR;
904 ev->iferror = err;
906 do {
908 * special case for GET_STATS:
909 * on success - sending reply and stats from
910 * inside of if_recv_msg(),
911 * on error - fall through.
913 if (ev->type == ISCSI_UEVENT_GET_STATS && !err)
914 break;
915 err = iscsi_if_send_reply(
916 NETLINK_CREDS(skb)->pid, nlh->nlmsg_seq,
917 nlh->nlmsg_type, 0, 0, ev, sizeof(*ev));
918 if (atomic_read(&z_reply.allocated) >=
919 z_reply.hiwat)
920 ev->iferror = -ENOMEM;
921 } while (err < 0 && err != -ECONNREFUSED);
922 skb_pull(skb, rlen);
924 kfree_skb(skb);
926 up(&rx_queue_sema);
930 * iSCSI connection attrs
932 #define iscsi_conn_int_attr_show(param, format) \
933 static ssize_t \
934 show_conn_int_param_##param(struct class_device *cdev, char *buf) \
936 uint32_t value = 0; \
937 struct iscsi_if_conn *conn = iscsi_cdev_to_if_conn(cdev); \
938 struct iscsi_internal *priv; \
940 priv = to_iscsi_internal(conn->host->transportt); \
941 if (priv->param_mask & (1 << param)) \
942 priv->iscsi_transport->get_param(conn->connh, param, &value); \
943 return snprintf(buf, 20, format"\n", value); \
946 #define iscsi_conn_int_attr(field, param, format) \
947 iscsi_conn_int_attr_show(param, format) \
948 static CLASS_DEVICE_ATTR(field, S_IRUGO, show_conn_int_param_##param, NULL);
950 iscsi_conn_int_attr(max_recv_dlength, ISCSI_PARAM_MAX_RECV_DLENGTH, "%u");
951 iscsi_conn_int_attr(max_xmit_dlength, ISCSI_PARAM_MAX_XMIT_DLENGTH, "%u");
952 iscsi_conn_int_attr(header_digest, ISCSI_PARAM_HDRDGST_EN, "%d");
953 iscsi_conn_int_attr(data_digest, ISCSI_PARAM_DATADGST_EN, "%d");
954 iscsi_conn_int_attr(ifmarker, ISCSI_PARAM_IFMARKER_EN, "%d");
955 iscsi_conn_int_attr(ofmarker, ISCSI_PARAM_OFMARKER_EN, "%d");
958 * iSCSI session attrs
960 #define iscsi_session_int_attr_show(param, format) \
961 static ssize_t \
962 show_session_int_param_##param(struct class_device *cdev, char *buf) \
964 uint32_t value = 0; \
965 struct iscsi_if_session *session = iscsi_cdev_to_if_session(cdev); \
966 struct Scsi_Host *shost = iscsi_if_session_to_shost(session); \
967 struct iscsi_internal *priv = to_iscsi_internal(shost->transportt); \
968 struct iscsi_if_conn *conn = NULL; \
969 unsigned long flags; \
971 spin_lock_irqsave(&connlock, flags); \
972 if (!list_empty(&session->connections)) \
973 conn = list_entry(session->connections.next, \
974 struct iscsi_if_conn, session_list); \
975 spin_unlock_irqrestore(&connlock, flags); \
977 if (conn && (priv->param_mask & (1 << param))) \
978 priv->iscsi_transport->get_param(conn->connh, param, &value);\
979 return snprintf(buf, 20, format"\n", value); \
982 #define iscsi_session_int_attr(field, param, format) \
983 iscsi_session_int_attr_show(param, format) \
984 static CLASS_DEVICE_ATTR(field, S_IRUGO, show_session_int_param_##param, NULL);
986 iscsi_session_int_attr(initial_r2t, ISCSI_PARAM_INITIAL_R2T_EN, "%d");
987 iscsi_session_int_attr(max_outstanding_r2t, ISCSI_PARAM_MAX_R2T, "%hu");
988 iscsi_session_int_attr(immediate_data, ISCSI_PARAM_IMM_DATA_EN, "%d");
989 iscsi_session_int_attr(first_burst_len, ISCSI_PARAM_FIRST_BURST, "%u");
990 iscsi_session_int_attr(max_burst_len, ISCSI_PARAM_MAX_BURST, "%u");
991 iscsi_session_int_attr(data_pdu_in_order, ISCSI_PARAM_PDU_INORDER_EN, "%d");
992 iscsi_session_int_attr(data_seq_in_order, ISCSI_PARAM_DATASEQ_INORDER_EN, "%d");
993 iscsi_session_int_attr(erl, ISCSI_PARAM_ERL, "%d");
995 #define SETUP_SESSION_RD_ATTR(field, param) \
996 if (priv->param_mask & (1 << param)) { \
997 priv->session_attrs[count] = &class_device_attr_##field;\
998 count++; \
1001 #define SETUP_CONN_RD_ATTR(field, param) \
1002 if (priv->param_mask & (1 << param)) { \
1003 priv->conn_attrs[count] = &class_device_attr_##field; \
1004 count++; \
1007 static int iscsi_is_session_dev(const struct device *dev)
1009 return dev->release == iscsi_if_session_dev_release;
1012 static int iscsi_session_match(struct attribute_container *cont,
1013 struct device *dev)
1015 struct iscsi_if_session *session;
1016 struct Scsi_Host *shost;
1017 struct iscsi_internal *priv;
1019 if (!iscsi_is_session_dev(dev))
1020 return 0;
1022 session = iscsi_dev_to_if_session(dev);
1023 shost = iscsi_if_session_to_shost(session);
1024 if (!shost->transportt)
1025 return 0;
1027 priv = to_iscsi_internal(shost->transportt);
1028 if (priv->session_cont.ac.class != &iscsi_session_class.class)
1029 return 0;
1031 return &priv->session_cont.ac == cont;
1034 static int iscsi_is_conn_dev(const struct device *dev)
1036 return dev->release == iscsi_if_conn_dev_release;
1039 static int iscsi_conn_match(struct attribute_container *cont,
1040 struct device *dev)
1042 struct iscsi_if_conn *conn;
1043 struct Scsi_Host *shost;
1044 struct iscsi_internal *priv;
1046 if (!iscsi_is_conn_dev(dev))
1047 return 0;
1049 conn = iscsi_dev_to_if_conn(dev);
1050 shost = conn->host;
1051 if (!shost->transportt)
1052 return 0;
1054 priv = to_iscsi_internal(shost->transportt);
1055 if (priv->conn_cont.ac.class != &iscsi_connection_class.class)
1056 return 0;
1058 return &priv->conn_cont.ac == cont;
1061 int iscsi_register_transport(struct iscsi_transport *tt)
1063 struct iscsi_internal *priv;
1064 unsigned long flags;
1065 int count = 0, err;
1067 BUG_ON(!tt);
1069 priv = iscsi_if_transport_lookup(tt);
1070 if (priv)
1071 return -EEXIST;
1073 priv = kmalloc(sizeof(*priv), GFP_KERNEL);
1074 if (!priv)
1075 return -ENOMEM;
1076 memset(priv, 0, sizeof(*priv));
1077 INIT_LIST_HEAD(&priv->list);
1078 INIT_LIST_HEAD(&priv->sessions);
1079 spin_lock_init(&priv->session_lock);
1080 priv->iscsi_transport = tt;
1082 priv->cdev.class = &iscsi_transport_class;
1083 snprintf(priv->cdev.class_id, BUS_ID_SIZE, "%s", tt->name);
1084 err = class_device_register(&priv->cdev);
1085 if (err)
1086 goto free_priv;
1088 err = sysfs_create_group(&priv->cdev.kobj, &iscsi_transport_group);
1089 if (err)
1090 goto unregister_cdev;
1092 /* setup parameters mask */
1093 priv->param_mask = 0xFFFFFFFF;
1094 if (!(tt->caps & CAP_MULTI_R2T))
1095 priv->param_mask &= ~(1 << ISCSI_PARAM_MAX_R2T);
1096 if (!(tt->caps & CAP_HDRDGST))
1097 priv->param_mask &= ~(1 << ISCSI_PARAM_HDRDGST_EN);
1098 if (!(tt->caps & CAP_DATADGST))
1099 priv->param_mask &= ~(1 << ISCSI_PARAM_DATADGST_EN);
1100 if (!(tt->caps & CAP_MARKERS)) {
1101 priv->param_mask &= ~(1 << ISCSI_PARAM_IFMARKER_EN);
1102 priv->param_mask &= ~(1 << ISCSI_PARAM_OFMARKER_EN);
1105 /* connection parameters */
1106 priv->conn_cont.ac.attrs = &priv->conn_attrs[0];
1107 priv->conn_cont.ac.class = &iscsi_connection_class.class;
1108 priv->conn_cont.ac.match = iscsi_conn_match;
1109 transport_container_register(&priv->conn_cont);
1111 SETUP_CONN_RD_ATTR(max_recv_dlength, ISCSI_PARAM_MAX_RECV_DLENGTH);
1112 SETUP_CONN_RD_ATTR(max_xmit_dlength, ISCSI_PARAM_MAX_XMIT_DLENGTH);
1113 SETUP_CONN_RD_ATTR(header_digest, ISCSI_PARAM_HDRDGST_EN);
1114 SETUP_CONN_RD_ATTR(data_digest, ISCSI_PARAM_DATADGST_EN);
1115 SETUP_CONN_RD_ATTR(ifmarker, ISCSI_PARAM_IFMARKER_EN);
1116 SETUP_CONN_RD_ATTR(ofmarker, ISCSI_PARAM_OFMARKER_EN);
1118 BUG_ON(count > ISCSI_CONN_ATTRS);
1119 priv->conn_attrs[count] = NULL;
1120 count = 0;
1122 /* session parameters */
1123 priv->session_cont.ac.attrs = &priv->session_attrs[0];
1124 priv->session_cont.ac.class = &iscsi_session_class.class;
1125 priv->session_cont.ac.match = iscsi_session_match;
1126 transport_container_register(&priv->session_cont);
1128 SETUP_SESSION_RD_ATTR(initial_r2t, ISCSI_PARAM_INITIAL_R2T_EN);
1129 SETUP_SESSION_RD_ATTR(max_outstanding_r2t, ISCSI_PARAM_MAX_R2T);
1130 SETUP_SESSION_RD_ATTR(immediate_data, ISCSI_PARAM_IMM_DATA_EN);
1131 SETUP_SESSION_RD_ATTR(first_burst_len, ISCSI_PARAM_FIRST_BURST);
1132 SETUP_SESSION_RD_ATTR(max_burst_len, ISCSI_PARAM_MAX_BURST);
1133 SETUP_SESSION_RD_ATTR(data_pdu_in_order, ISCSI_PARAM_PDU_INORDER_EN);
1134 SETUP_SESSION_RD_ATTR(data_seq_in_order,ISCSI_PARAM_DATASEQ_INORDER_EN)
1135 SETUP_SESSION_RD_ATTR(erl, ISCSI_PARAM_ERL);
1137 BUG_ON(count > ISCSI_SESSION_ATTRS);
1138 priv->session_attrs[count] = NULL;
1140 spin_lock_irqsave(&iscsi_transport_lock, flags);
1141 list_add(&priv->list, &iscsi_transports);
1142 spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1144 printk(KERN_NOTICE "iscsi: registered transport (%s)\n", tt->name);
1145 return 0;
1147 unregister_cdev:
1148 class_device_unregister(&priv->cdev);
1149 free_priv:
1150 kfree(priv);
1151 return err;
1153 EXPORT_SYMBOL_GPL(iscsi_register_transport);
1155 int iscsi_unregister_transport(struct iscsi_transport *tt)
1157 struct iscsi_internal *priv;
1158 unsigned long flags;
1160 BUG_ON(!tt);
1162 down(&rx_queue_sema);
1164 priv = iscsi_if_transport_lookup(tt);
1165 BUG_ON (!priv);
1167 spin_lock_irqsave(&priv->session_lock, flags);
1168 if (!list_empty(&priv->sessions)) {
1169 spin_unlock_irqrestore(&priv->session_lock, flags);
1170 up(&rx_queue_sema);
1171 return -EPERM;
1173 spin_unlock_irqrestore(&priv->session_lock, flags);
1175 spin_lock_irqsave(&iscsi_transport_lock, flags);
1176 list_del(&priv->list);
1177 spin_unlock_irqrestore(&iscsi_transport_lock, flags);
1179 transport_container_unregister(&priv->conn_cont);
1180 transport_container_unregister(&priv->session_cont);
1182 sysfs_remove_group(&priv->cdev.kobj, &iscsi_transport_group);
1183 class_device_unregister(&priv->cdev);
1184 up(&rx_queue_sema);
1186 return 0;
1188 EXPORT_SYMBOL_GPL(iscsi_unregister_transport);
1190 static int
1191 iscsi_rcv_nl_event(struct notifier_block *this, unsigned long event, void *ptr)
1193 struct netlink_notify *n = ptr;
1195 if (event == NETLINK_URELEASE &&
1196 n->protocol == NETLINK_ISCSI && n->pid) {
1197 struct iscsi_if_conn *conn;
1198 unsigned long flags;
1200 mempool_zone_complete(&z_reply);
1201 spin_lock_irqsave(&connlock, flags);
1202 list_for_each_entry(conn, &connlist, conn_list) {
1203 mempool_zone_complete(&conn->z_error);
1204 mempool_zone_complete(&conn->z_pdu);
1206 spin_unlock_irqrestore(&connlock, flags);
1209 return NOTIFY_DONE;
1212 static struct notifier_block iscsi_nl_notifier = {
1213 .notifier_call = iscsi_rcv_nl_event,
1216 static __init int iscsi_transport_init(void)
1218 int err;
1220 err = class_register(&iscsi_transport_class);
1221 if (err)
1222 return err;
1224 err = transport_class_register(&iscsi_connection_class);
1225 if (err)
1226 goto unregister_transport_class;
1228 err = transport_class_register(&iscsi_session_class);
1229 if (err)
1230 goto unregister_conn_class;
1232 err = netlink_register_notifier(&iscsi_nl_notifier);
1233 if (err)
1234 goto unregister_session_class;
1236 nls = netlink_kernel_create(NETLINK_ISCSI, 1, iscsi_if_rx,
1237 THIS_MODULE);
1238 if (!nls) {
1239 err = -ENOBUFS;
1240 goto unregister_notifier;
1243 err = mempool_zone_init(&z_reply, Z_MAX_REPLY,
1244 NLMSG_SPACE(sizeof(struct iscsi_uevent)), Z_HIWAT_REPLY);
1245 if (!err)
1246 return 0;
1248 sock_release(nls->sk_socket);
1249 unregister_notifier:
1250 netlink_unregister_notifier(&iscsi_nl_notifier);
1251 unregister_session_class:
1252 transport_class_unregister(&iscsi_session_class);
1253 unregister_conn_class:
1254 transport_class_unregister(&iscsi_connection_class);
1255 unregister_transport_class:
1256 class_unregister(&iscsi_transport_class);
1257 return err;
1260 static void __exit iscsi_transport_exit(void)
1262 mempool_destroy(z_reply.pool);
1263 sock_release(nls->sk_socket);
1264 netlink_unregister_notifier(&iscsi_nl_notifier);
1265 transport_class_unregister(&iscsi_connection_class);
1266 transport_class_unregister(&iscsi_session_class);
1267 class_unregister(&iscsi_transport_class);
1270 module_init(iscsi_transport_init);
1271 module_exit(iscsi_transport_exit);
1273 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
1274 "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
1275 "Alex Aizman <itn780@yahoo.com>");
1276 MODULE_DESCRIPTION("iSCSI Transport Interface");
1277 MODULE_LICENSE("GPL");