Merge master.kernel.org:/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6

1 files changed, 448 insertions, 411 deletions

diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index e08462d..59a1c9d 100644
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -21,11 +21,9 @@
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 #include <linux/module.h>
-#include <linux/string.h>
-#include <linux/slab.h>
 #include <linux/mempool.h>
+#include <linux/mutex.h>
 #include <net/tcp.h>
-
 #include <scsi/scsi.h>
 #include <scsi/scsi_host.h>
 #include <scsi/scsi_device.h>
@@ -45,11 +43,6 @@ struct iscsi_internal {
 	 */
 	struct list_head sessions;
 	/*
-	 * lock to serialize access to the sessions list which must
-	 * be taken after the rx_queue_sema
-	 */
-	spinlock_t session_lock;
-	/*
 	 * based on transport capabilities, at register time we set these
 	 * bits to tell the transport class it wants attributes displayed
 	 * in sysfs or that it can support different iSCSI Data-Path
@@ -70,7 +63,7 @@ struct iscsi_internal {
 /*
  * list of registered transports and lock that must
  * be held while accessing list. The iscsi_transport_lock must
- * be acquired after the rx_queue_sema.
+ * be acquired after the rx_queue_mutex.
  */
 static LIST_HEAD(iscsi_transports);
 static DEFINE_SPINLOCK(iscsi_transport_lock);
@@ -145,7 +138,7 @@ static DECLARE_TRANSPORT_CLASS(iscsi_connection_class,
 
 static struct sock *nls;
 static int daemon_pid;
-static DECLARE_MUTEX(rx_queue_sema);
+static DEFINE_MUTEX(rx_queue_mutex);
 
 struct mempool_zone {
 	mempool_t *pool;
@@ -156,7 +149,7 @@ struct mempool_zone {
 	spinlock_t freelock;
 };
 
-static struct mempool_zone z_reply;
+static struct mempool_zone *z_reply;
 
 /*
  * Z_MAX_* - actual mempool size allocated at the mempool_zone_init() time
@@ -171,50 +164,271 @@ static struct mempool_zone z_reply;
 #define Z_MAX_ERROR	16
 #define Z_HIWAT_ERROR	12
 
-struct iscsi_if_conn {
-	struct list_head conn_list;	/* item in connlist */
-	struct list_head session_list;	/* item in session->connections */
-	iscsi_connh_t connh;
-	int active;			/* must be accessed with the connlock */
-	struct Scsi_Host *host;		/* originated shost */
-	struct device dev;		/* sysfs transport/container device */
-	struct iscsi_transport *transport;
-	struct mempool_zone z_error;
-	struct mempool_zone z_pdu;
-	struct list_head freequeue;
-};
+static LIST_HEAD(connlist);
+static DEFINE_SPINLOCK(connlock);
 
-#define iscsi_dev_to_if_conn(_dev) \
-	container_of(_dev, struct iscsi_if_conn, dev)
+/*
+ * The following functions can be used by LLDs that allocate
+ * their own scsi_hosts or by software iscsi LLDs
+ */
+static void iscsi_session_release(struct device *dev)
+{
+	struct iscsi_cls_session *session = iscsi_dev_to_session(dev);
+	struct iscsi_transport *transport = session->transport;
+	struct Scsi_Host *shost;
 
-#define iscsi_cdev_to_if_conn(_cdev) \
-	iscsi_dev_to_if_conn(_cdev->dev)
+	shost = iscsi_session_to_shost(session);
+	scsi_host_put(shost);
+	kfree(session);
+	module_put(transport->owner);
+}
 
-static LIST_HEAD(connlist);
-static DEFINE_SPINLOCK(connlock);
+static int iscsi_is_session_dev(const struct device *dev)
+{
+	return dev->release == iscsi_session_release;
+}
 
-struct iscsi_if_session {
-	struct list_head list;	/* item in session_list */
-	struct list_head connections;
-	iscsi_sessionh_t sessionh;
-	struct iscsi_transport *transport;
-	struct device dev;	/* sysfs transport/container device */
-};
+/**
+ * iscsi_create_session - create iscsi class session
+ * @shost: scsi host
+ * @transport: iscsi transport
+ *
+ * This can be called from a LLD or iscsi_transport
+ **/
+struct iscsi_cls_session *
+iscsi_create_session(struct Scsi_Host *shost, struct iscsi_transport *transport)
+{
+	struct iscsi_cls_session *session;
+	int err;
+
+	if (!try_module_get(transport->owner))
+		return NULL;
+
+	session = kzalloc(sizeof(*session), GFP_KERNEL);
+	if (!session)
+		goto module_put;
+	session->transport = transport;
+
+	/* this is released in the dev's release function */
+	scsi_host_get(shost);
+	snprintf(session->dev.bus_id, BUS_ID_SIZE, "session%u", shost->host_no);
+	session->dev.parent = &shost->shost_gendev;
+	session->dev.release = iscsi_session_release;
+	err = device_register(&session->dev);
+	if (err) {
+		dev_printk(KERN_ERR, &session->dev, "iscsi: could not "
+			   "register session's dev\n");
+		goto free_session;
+	}
+	transport_register_device(&session->dev);
+
+	return session;
+
+free_session:
+	kfree(session);
+module_put:
+	module_put(transport->owner);
+	return NULL;
+}
+
+EXPORT_SYMBOL_GPL(iscsi_create_session);
+
+/**
+ * iscsi_destroy_session - destroy iscsi session
+ * @session: iscsi_session
+ *
+ * Can be called by a LLD or iscsi_transport. There must not be
+ * any running connections.
+ **/
+int iscsi_destroy_session(struct iscsi_cls_session *session)
+{
+	transport_unregister_device(&session->dev);
+	device_unregister(&session->dev);
+	return 0;
+}
+
+EXPORT_SYMBOL_GPL(iscsi_destroy_session);
+
+static void iscsi_conn_release(struct device *dev)
+{
+	struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev);
+	struct device *parent = conn->dev.parent;
+
+	kfree(conn);
+	put_device(parent);
+}
+
+static int iscsi_is_conn_dev(const struct device *dev)
+{
+	return dev->release == iscsi_conn_release;
+}
+
+/**
+ * iscsi_create_conn - create iscsi class connection
+ * @session: iscsi cls session
+ * @cid: connection id
+ *
+ * This can be called from a LLD or iscsi_transport. The connection
+ * is child of the session so cid must be unique for all connections
+ * on the session.
+ **/
+struct iscsi_cls_conn *
+iscsi_create_conn(struct iscsi_cls_session *session, uint32_t cid)
+{
+	struct iscsi_transport *transport = session->transport;
+	struct Scsi_Host *shost = iscsi_session_to_shost(session);
+	struct iscsi_cls_conn *conn;
+	int err;
+
+	conn = kzalloc(sizeof(*conn) + transport->conndata_size, GFP_KERNEL);
+	if (!conn)
+		return NULL;
+
+	if (transport->conndata_size)
+		conn->dd_data = &conn[1];
+
+	INIT_LIST_HEAD(&conn->conn_list);
+	conn->transport = transport;
+
+	/* this is released in the dev's release function */
+	if (!get_device(&session->dev))
+		goto free_conn;
+	snprintf(conn->dev.bus_id, BUS_ID_SIZE, "connection%d:%u",
+		 shost->host_no, cid);
+	conn->dev.parent = &session->dev;
+	conn->dev.release = iscsi_conn_release;
+	err = device_register(&conn->dev);
+	if (err) {
+		dev_printk(KERN_ERR, &conn->dev, "iscsi: could not register "
+			   "connection's dev\n");
+		goto release_parent_ref;
+	}
+	transport_register_device(&conn->dev);
+	return conn;
+
+release_parent_ref:
+	put_device(&session->dev);
+free_conn:
+	kfree(conn);
+	return NULL;
+}
+
+EXPORT_SYMBOL_GPL(iscsi_create_conn);
+
+/**
+ * iscsi_destroy_conn - destroy iscsi class connection
+ * @session: iscsi cls session
+ *
+ * This can be called from a LLD or iscsi_transport.
+ **/
+int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
+{
+	transport_unregister_device(&conn->dev);
+	device_unregister(&conn->dev);
+	return 0;
+}
+
+EXPORT_SYMBOL_GPL(iscsi_destroy_conn);
+
+/*
+ * These functions are used only by software iscsi_transports
+ * which do not allocate and more their scsi_hosts since this
+ * is initiated from userspace.
+ */
+
+/*
+ * iSCSI Session's hostdata organization:
+ *
+ *    *------------------* <== hostdata_session(host->hostdata)
+ *    | ptr to class sess|
+ *    |------------------| <== iscsi_hostdata(host->hostdata)
+ *    | transport's data |
+ *    *------------------*
+ */
+
+#define hostdata_privsize(_t)	(sizeof(unsigned long) + _t->hostdata_size + \
+				 _t->hostdata_size % sizeof(unsigned long))
+
+#define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
+
+/**
+ * iscsi_transport_create_session - create iscsi cls session and host
+ * scsit: scsi transport template
+ * transport: iscsi transport template
+ *
+ * This can be used by software iscsi_transports that allocate
+ * a session per scsi host.
+ **/
+struct Scsi_Host *
+iscsi_transport_create_session(struct scsi_transport_template *scsit,
+			       struct iscsi_transport *transport)
+{
+	struct iscsi_cls_session *session;
+	struct Scsi_Host *shost;
+
+	shost = scsi_host_alloc(transport->host_template,
+				hostdata_privsize(transport));
+	if (!shost) {
+		printk(KERN_ERR "iscsi: can not allocate SCSI host for "
+			"session\n");
+		return NULL;
+	}
+
+	shost->max_id = 1;
+	shost->max_channel = 0;
+	shost->max_lun = transport->max_lun;
+	shost->max_cmd_len = transport->max_cmd_len;
+	shost->transportt = scsit;
+	shost->transportt->create_work_queue = 1;
+
+	if (scsi_add_host(shost, NULL))
+		goto free_host;
+
+	session = iscsi_create_session(shost, transport);
+	if (!session)
+		goto remove_host;
 
-#define iscsi_dev_to_if_session(_dev) \
-	container_of(_dev, struct iscsi_if_session, dev)
+	*(unsigned long*)shost->hostdata = (unsigned long)session;
+	return shost;
+
+remove_host:
+	scsi_remove_host(shost);
+free_host:
+	scsi_host_put(shost);
+	return NULL;
+}
 
-#define iscsi_cdev_to_if_session(_cdev) \
-	iscsi_dev_to_if_session(_cdev->dev)
+EXPORT_SYMBOL_GPL(iscsi_transport_create_session);
 
-#define iscsi_if_session_to_shost(_session) \
-	dev_to_shost(_session->dev.parent)
+/**
+ * iscsi_transport_destroy_session - destroy session and scsi host
+ * shost: scsi host
+ *
+ * This can be used by software iscsi_transports that allocate
+ * a session per scsi host.
+ **/
+int iscsi_transport_destroy_session(struct Scsi_Host *shost)
+{
+	struct iscsi_cls_session *session;
 
-static struct iscsi_if_conn*
+	scsi_remove_host(shost);
+	session = hostdata_session(shost->hostdata);
+	iscsi_destroy_session(session);
+	/* ref from host alloc */
+	scsi_host_put(shost);
+	return 0;
+}
+
+EXPORT_SYMBOL_GPL(iscsi_transport_destroy_session);
+
+/*
+ * iscsi interface functions
+ */
+static struct iscsi_cls_conn*
 iscsi_if_find_conn(uint64_t key)
 {
 	unsigned long flags;
-	struct iscsi_if_conn *conn;
+	struct iscsi_cls_conn *conn;
 
 	spin_lock_irqsave(&connlock, flags);
 	list_for_each_entry(conn, &connlist, conn_list)
@@ -249,7 +463,7 @@ static inline struct list_head *skb_to_lh(struct sk_buff *skb)
 }
 
 static void*
-mempool_zone_alloc_skb(gfp_t gfp_mask, void *pool_data)
+mempool_zone_alloc_skb(unsigned int gfp_mask, void *pool_data)
 {
 	struct mempool_zone *zone = pool_data;
 
@@ -281,14 +495,21 @@ mempool_zone_complete(struct mempool_zone *zone)
 	spin_unlock_irqrestore(&zone->freelock, flags);
 }
 
-static int
-mempool_zone_init(struct mempool_zone *zp, unsigned max, unsigned size,
-		unsigned hiwat)
+static struct mempool_zone *
+mempool_zone_init(unsigned max, unsigned size, unsigned hiwat)
 {
+	struct mempool_zone *zp;
+
+	zp = kzalloc(sizeof(*zp), GFP_KERNEL);
+	if (!zp)
+		return NULL;
+
 	zp->pool = mempool_create(max, mempool_zone_alloc_skb,
 				  mempool_zone_free_skb, zp);
-	if (!zp->pool)
-		return -ENOMEM;
+	if (!zp->pool) {
+		kfree(zp);
+		return NULL;
+	}
 
 	zp->size = size;
 	zp->hiwat = hiwat;
@@ -297,9 +518,14 @@ mempool_zone_init(struct mempool_zone *zp, unsigned max, unsigned size,
 	spin_lock_init(&zp->freelock);
 	atomic_set(&zp->allocated, 0);
 
-	return 0;
+	return zp;
 }
 
+static void mempool_zone_destroy(struct mempool_zone *zp)
+{
+	mempool_destroy(zp->pool);
+	kfree(zp);
+}
 
 static struct sk_buff*
 mempool_zone_get_skb(struct mempool_zone *zone)
@@ -339,7 +565,7 @@ int iscsi_recv_pdu(iscsi_connh_t connh, struct iscsi_hdr *hdr,
 	struct nlmsghdr	*nlh;
 	struct sk_buff *skb;
 	struct iscsi_uevent *ev;
-	struct iscsi_if_conn *conn;
+	struct iscsi_cls_conn *conn;
 	char *pdu;
 	int len = NLMSG_SPACE(sizeof(*ev) + sizeof(struct iscsi_hdr) +
 			      data_size);
@@ -347,13 +573,13 @@ int iscsi_recv_pdu(iscsi_connh_t connh, struct iscsi_hdr *hdr,
 	conn = iscsi_if_find_conn(connh);
 	BUG_ON(!conn);
 
-	mempool_zone_complete(&conn->z_pdu);
+	mempool_zone_complete(conn->z_pdu);
 
-	skb = mempool_zone_get_skb(&conn->z_pdu);
+	skb = mempool_zone_get_skb(conn->z_pdu);
 	if (!skb) {
 		iscsi_conn_error(connh, ISCSI_ERR_CONN_FAILED);
-		printk(KERN_ERR "iscsi%d: can not deliver control PDU: OOM\n",
-		       conn->host->host_no);
+		dev_printk(KERN_ERR, &conn->dev, "iscsi: can not deliver "
+			   "control PDU: OOM\n");
 		return -ENOMEM;
 	}
 
@@ -362,14 +588,14 @@ int iscsi_recv_pdu(iscsi_connh_t connh, struct iscsi_hdr *hdr,
 	memset(ev, 0, sizeof(*ev));
 	ev->transport_handle = iscsi_handle(conn->transport);
 	ev->type = ISCSI_KEVENT_RECV_PDU;
-	if (atomic_read(&conn->z_pdu.allocated) >= conn->z_pdu.hiwat)
+	if (atomic_read(&conn->z_pdu->allocated) >= conn->z_pdu->hiwat)
 		ev->iferror = -ENOMEM;
 	ev->r.recv_req.conn_handle = connh;
 	pdu = (char*)ev + sizeof(*ev);
 	memcpy(pdu, hdr, sizeof(struct iscsi_hdr));
 	memcpy(pdu + sizeof(struct iscsi_hdr), data, data_size);
 
-	return iscsi_unicast_skb(&conn->z_pdu, skb);
+	return iscsi_unicast_skb(conn->z_pdu, skb);
 }
 EXPORT_SYMBOL_GPL(iscsi_recv_pdu);
 
@@ -378,18 +604,18 @@ void iscsi_conn_error(iscsi_connh_t connh, enum iscsi_err error)
 	struct nlmsghdr	*nlh;
 	struct sk_buff	*skb;
 	struct iscsi_uevent *ev;
-	struct iscsi_if_conn *conn;
+	struct iscsi_cls_conn *conn;
 	int len = NLMSG_SPACE(sizeof(*ev));
 
 	conn = iscsi_if_find_conn(connh);
 	BUG_ON(!conn);
 
-	mempool_zone_complete(&conn->z_error);
+	mempool_zone_complete(conn->z_error);
 
-	skb = mempool_zone_get_skb(&conn->z_error);
+	skb = mempool_zone_get_skb(conn->z_error);
 	if (!skb) {
-		printk(KERN_ERR "iscsi%d: gracefully ignored conn error (%d)\n",
-		       conn->host->host_no, error);
+		dev_printk(KERN_ERR, &conn->dev, "iscsi: gracefully ignored "
+			  "conn error (%d)\n", error);
 		return;
 	}
 
@@ -397,15 +623,15 @@ void iscsi_conn_error(iscsi_connh_t connh, enum iscsi_err error)
 	ev = NLMSG_DATA(nlh);
 	ev->transport_handle = iscsi_handle(conn->transport);
 	ev->type = ISCSI_KEVENT_CONN_ERROR;
-	if (atomic_read(&conn->z_error.allocated) >= conn->z_error.hiwat)
+	if (atomic_read(&conn->z_error->allocated) >= conn->z_error->hiwat)
 		ev->iferror = -ENOMEM;
 	ev->r.connerror.error = error;
 	ev->r.connerror.conn_handle = connh;
 
-	iscsi_unicast_skb(&conn->z_error, skb);
+	iscsi_unicast_skb(conn->z_error, skb);
 
-	printk(KERN_INFO "iscsi%d: detected conn error (%d)\n",
-	       conn->host->host_no, error);
+	dev_printk(KERN_INFO, &conn->dev, "iscsi: detected conn error (%d)\n",
+		   error);
 }
 EXPORT_SYMBOL_GPL(iscsi_conn_error);
 
@@ -419,9 +645,9 @@ iscsi_if_send_reply(int pid, int seq, int type, int done, int multi,
 	int flags = multi ? NLM_F_MULTI : 0;
 	int t = done ? NLMSG_DONE : type;
 
-	mempool_zone_complete(&z_reply);
+	mempool_zone_complete(z_reply);
 
-	skb = mempool_zone_get_skb(&z_reply);
+	skb = mempool_zone_get_skb(z_reply);
 	/*
 	 * FIXME:
 	 * user is supposed to react on iferror == -ENOMEM;
@@ -432,366 +658,197 @@ iscsi_if_send_reply(int pid, int seq, int type, int done, int multi,
 	nlh = __nlmsg_put(skb, pid, seq, t, (len - sizeof(*nlh)), 0);
 	nlh->nlmsg_flags = flags;
 	memcpy(NLMSG_DATA(nlh), payload, size);
-	return iscsi_unicast_skb(&z_reply, skb);
+	return iscsi_unicast_skb(z_reply, skb);
 }
 
-/*
- * iSCSI Session's hostdata organization:
- *
- *    *------------------* <== host->hostdata
- *    | transport        |
- *    |------------------| <== iscsi_hostdata(host->hostdata)
- *    | transport's data |
- *    |------------------| <== hostdata_session(host->hostdata)
- *    | interface's data |
- *    *------------------*
- */
+static int
+iscsi_if_get_stats(struct iscsi_transport *transport, struct sk_buff *skb,
+		   struct nlmsghdr *nlh)
+{
+	struct iscsi_uevent *ev = NLMSG_DATA(nlh);
+	struct iscsi_stats *stats;
+	struct sk_buff *skbstat;
+	struct iscsi_cls_conn *conn;
+	struct nlmsghdr	*nlhstat;
+	struct iscsi_uevent *evstat;
+	int len = NLMSG_SPACE(sizeof(*ev) +
+			      sizeof(struct iscsi_stats) +
+			      sizeof(struct iscsi_stats_custom) *
+			      ISCSI_STATS_CUSTOM_MAX);
+	int err = 0;
 
-#define hostdata_privsize(_t)	(sizeof(unsigned long) + _t->hostdata_size + \
-				 _t->hostdata_size % sizeof(unsigned long) + \
-				 sizeof(struct iscsi_if_session))
+	conn = iscsi_if_find_conn(ev->u.get_stats.conn_handle);
+	if (!conn)
+		return -EEXIST;
 
-#define hostdata_session(_hostdata) ((void*)_hostdata + sizeof(unsigned long) + \
-			((struct iscsi_transport *) \
-			 iscsi_ptr(*(uint64_t *)_hostdata))->hostdata_size)
+	do {
+		int actual_size;
 
-static void iscsi_if_session_dev_release(struct device *dev)
-{
-	struct iscsi_if_session *session = iscsi_dev_to_if_session(dev);
-	struct iscsi_transport *transport = session->transport;
-	struct Scsi_Host *shost = iscsi_if_session_to_shost(session);
-	struct iscsi_if_conn *conn, *tmp;
-	unsigned long flags;
+		mempool_zone_complete(conn->z_pdu);
 
-	/* now free connections */
-	spin_lock_irqsave(&connlock, flags);
-	list_for_each_entry_safe(conn, tmp, &session->connections,
-				 session_list) {
-		list_del(&conn->session_list);
-		mempool_destroy(conn->z_pdu.pool);
-		mempool_destroy(conn->z_error.pool);
-		kfree(conn);
-	}
-	spin_unlock_irqrestore(&connlock, flags);
-	scsi_host_put(shost);
-	module_put(transport->owner);
+		skbstat = mempool_zone_get_skb(conn->z_pdu);
+		if (!skbstat) {
+			dev_printk(KERN_ERR, &conn->dev, "iscsi: can not "
+				   "deliver stats: OOM\n");
+			return -ENOMEM;
+		}
+
+		nlhstat = __nlmsg_put(skbstat, daemon_pid, 0, 0,
+				      (len - sizeof(*nlhstat)), 0);
+		evstat = NLMSG_DATA(nlhstat);
+		memset(evstat, 0, sizeof(*evstat));
+		evstat->transport_handle = iscsi_handle(conn->transport);
+		evstat->type = nlh->nlmsg_type;
+		if (atomic_read(&conn->z_pdu->allocated) >= conn->z_pdu->hiwat)
+			evstat->iferror = -ENOMEM;
+		evstat->u.get_stats.conn_handle =
+			ev->u.get_stats.conn_handle;
+		stats = (struct iscsi_stats *)
+			((char*)evstat + sizeof(*evstat));
+		memset(stats, 0, sizeof(*stats));
+
+		transport->get_stats(ev->u.get_stats.conn_handle, stats);
+		actual_size = NLMSG_SPACE(sizeof(struct iscsi_uevent) +
+					  sizeof(struct iscsi_stats) +
+					  sizeof(struct iscsi_stats_custom) *
+					  stats->custom_length);
+		actual_size -= sizeof(*nlhstat);
+		actual_size = NLMSG_LENGTH(actual_size);
+		skb_trim(skb, NLMSG_ALIGN(actual_size));
+		nlhstat->nlmsg_len = actual_size;
+
+		err = iscsi_unicast_skb(conn->z_pdu, skbstat);
+	} while (err < 0 && err != -ECONNREFUSED);
+
+	return err;
 }
 
 static int
 iscsi_if_create_session(struct iscsi_internal *priv, struct iscsi_uevent *ev)
 {
 	struct iscsi_transport *transport = priv->iscsi_transport;
-	struct iscsi_if_session *session;
 	struct Scsi_Host *shost;
-	unsigned long flags;
-	int error;
-
-	if (!try_module_get(transport->owner))
-		return -EPERM;
 
-	shost = scsi_host_alloc(transport->host_template,
-				hostdata_privsize(transport));
-	if (!shost) {
-		ev->r.c_session_ret.session_handle = iscsi_handle(NULL);
-		printk(KERN_ERR "iscsi: can not allocate SCSI host for "
-		       "session\n");
-		error = -ENOMEM;
-		goto out_module_put;
-	}
-	shost->max_id = 1;
-	shost->max_channel = 0;
-	shost->max_lun = transport->max_lun;
-	shost->max_cmd_len = transport->max_cmd_len;
-	shost->transportt = &priv->t;
-
-	/* store struct iscsi_transport in hostdata */
-	*(uint64_t*)shost->hostdata = ev->transport_handle;
+	if (!transport->create_session)
+		return -EINVAL;
 
-	ev->r.c_session_ret.session_handle = transport->create_session(
-					ev->u.c_session.initial_cmdsn, shost);
-	if (ev->r.c_session_ret.session_handle == iscsi_handle(NULL)) {
-		error = 0;
-		goto out_host_put;
-	}
+	shost = transport->create_session(&priv->t,
+					  ev->u.c_session.initial_cmdsn);
+	if (!shost)
+		return -ENOMEM;
 
-	/* host_no becomes assigned SID */
+	ev->r.c_session_ret.session_handle = iscsi_handle(iscsi_hostdata(shost->hostdata));
 	ev->r.c_session_ret.sid = shost->host_no;
-	/* initialize session */
-	session = hostdata_session(shost->hostdata);
-	INIT_LIST_HEAD(&session->connections);
-	INIT_LIST_HEAD(&session->list);
-	session->sessionh = ev->r.c_session_ret.session_handle;
-	session->transport = transport;
-
-	error = scsi_add_host(shost, NULL);
-	if (error)
-		goto out_destroy_session;
-
-	/*
-	 * this is released in the dev's release function)
-	 */
-	scsi_host_get(shost);
-	snprintf(session->dev.bus_id, BUS_ID_SIZE, "session%u", shost->host_no);
-	session->dev.parent = &shost->shost_gendev;
-	session->dev.release = iscsi_if_session_dev_release;
-	error = device_register(&session->dev);
-	if (error) {
-		printk(KERN_ERR "iscsi: could not register session%d's dev\n",
-		       shost->host_no);
-		goto out_remove_host;
-	}
-	transport_register_device(&session->dev);
-
-	/* add this session to the list of active sessions */
-	spin_lock_irqsave(&priv->session_lock, flags);
-	list_add(&session->list, &priv->sessions);
-	spin_unlock_irqrestore(&priv->session_lock, flags);
-
 	return 0;
-
-out_remove_host:
-	scsi_remove_host(shost);
-out_destroy_session:
-	transport->destroy_session(ev->r.c_session_ret.session_handle);
-	ev->r.c_session_ret.session_handle = iscsi_handle(NULL);
-out_host_put:
-	scsi_host_put(shost);
-out_module_put:
-	module_put(transport->owner);
-	return error;
 }
 
 static int
 iscsi_if_destroy_session(struct iscsi_internal *priv, struct iscsi_uevent *ev)
 {
 	struct iscsi_transport *transport = priv->iscsi_transport;
+
 	struct Scsi_Host *shost;
-	struct iscsi_if_session *session;
-	unsigned long flags;
-	struct iscsi_if_conn *conn;
-	int error = 0;
+
+	if (!transport->destroy_session)
+		return -EINVAL;
 
 	shost = scsi_host_lookup(ev->u.d_session.sid);
 	if (shost == ERR_PTR(-ENXIO))
 		return -EEXIST;
-	session = hostdata_session(shost->hostdata);
 
-	/* check if we have active connections */
-	spin_lock_irqsave(&connlock, flags);
-	list_for_each_entry(conn, &session->connections, session_list) {
-		if (conn->active) {
-			printk(KERN_ERR "iscsi%d: can not destroy session: "
-			       "has active connection (%p)\n",
-			       shost->host_no, iscsi_ptr(conn->connh));
-			spin_unlock_irqrestore(&connlock, flags);
-			error = EIO;
-			goto out_release_ref;
-		}
-	}
-	spin_unlock_irqrestore(&connlock, flags);
-
-	scsi_remove_host(shost);
-	transport->destroy_session(ev->u.d_session.session_handle);
-	transport_unregister_device(&session->dev);
-	device_unregister(&session->dev);
-
-	/* remove this session from the list of active sessions */
-	spin_lock_irqsave(&priv->session_lock, flags);
-	list_del(&session->list);
-	spin_unlock_irqrestore(&priv->session_lock, flags);
-
-	/* ref from host alloc */
-	scsi_host_put(shost);
-out_release_ref:
-	/* ref from host lookup */
-	scsi_host_put(shost);
-	return error;
-}
-
-static void iscsi_if_conn_dev_release(struct device *dev)
-{
-	struct iscsi_if_conn *conn = iscsi_dev_to_if_conn(dev);
-	struct Scsi_Host *shost = conn->host;
-
-	scsi_host_put(shost);
+	if (transport->destroy_session)
+		transport->destroy_session(shost);
+        /* ref from host lookup */
+        scsi_host_put(shost);
+	return 0;
 }
 
 static int
-iscsi_if_create_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
-{
-	struct iscsi_if_session *session;
+iscsi_if_create_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev){
 	struct Scsi_Host *shost;
-	struct iscsi_if_conn *conn;
+	struct iscsi_cls_conn *conn;
 	unsigned long flags;
-	int error;
+
+	if (!transport->create_conn)
+		return -EINVAL;
 
 	shost = scsi_host_lookup(ev->u.c_conn.sid);
 	if (shost == ERR_PTR(-ENXIO))
 		return -EEXIST;
-	session = hostdata_session(shost->hostdata);
 
-	conn = kmalloc(sizeof(struct iscsi_if_conn), GFP_KERNEL);
-	if (!conn) {
-		error = -ENOMEM;
-		goto out_release_ref;
-	}
-	memset(conn, 0, sizeof(struct iscsi_if_conn));
-	INIT_LIST_HEAD(&conn->session_list);
-	INIT_LIST_HEAD(&conn->conn_list);
-	conn->host = shost;
-	conn->transport = transport;
+	conn = transport->create_conn(shost, ev->u.c_conn.cid);
+	if (!conn)
+		goto release_ref;
 
-	error = mempool_zone_init(&conn->z_pdu, Z_MAX_PDU,
+	conn->z_pdu = mempool_zone_init(Z_MAX_PDU,
 			NLMSG_SPACE(sizeof(struct iscsi_uevent) +
 				    sizeof(struct iscsi_hdr) +
 				    DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH),
 			Z_HIWAT_PDU);
-	if (error) {
-		printk(KERN_ERR "iscsi%d: can not allocate pdu zone for new "
-		       "conn\n", shost->host_no);
-		goto out_free_conn;
+	if (!conn->z_pdu) {
+		dev_printk(KERN_ERR, &conn->dev, "iscsi: can not allocate "
+			   "pdu zone for new conn\n");
+		goto destroy_conn;
 	}
-	error = mempool_zone_init(&conn->z_error, Z_MAX_ERROR,
+
+	conn->z_error = mempool_zone_init(Z_MAX_ERROR,
 			NLMSG_SPACE(sizeof(struct iscsi_uevent)),
 			Z_HIWAT_ERROR);
-	if (error) {
-		printk(KERN_ERR "iscsi%d: can not allocate error zone for "
-		       "new conn\n", shost->host_no);
-		goto out_free_pdu_pool;
-	}
-
-	ev->r.handle = transport->create_conn(ev->u.c_conn.session_handle,
-					ev->u.c_conn.cid);
-	if (!ev->r.handle) {
-		error = -ENODEV;
-		goto out_free_error_pool;
+	if (!conn->z_error) {
+		dev_printk(KERN_ERR, &conn->dev, "iscsi: can not allocate "
+			   "error zone for new conn\n");
+		goto free_pdu_pool;
 	}
 
-	conn->connh = ev->r.handle;
-
-	/*
-	 * this is released in the dev's release function
-	 */
-	if (!scsi_host_get(shost))
-		goto out_destroy_conn;
-	snprintf(conn->dev.bus_id, BUS_ID_SIZE, "connection%d:%u",
-		 shost->host_no, ev->u.c_conn.cid);
-	conn->dev.parent = &session->dev;
-	conn->dev.release = iscsi_if_conn_dev_release;
-	error = device_register(&conn->dev);
-	if (error) {
-		printk(KERN_ERR "iscsi%d: could not register connections%u "
-		       "dev\n", shost->host_no, ev->u.c_conn.cid);
-		goto out_release_parent_ref;
-	}
-	transport_register_device(&conn->dev);
+	ev->r.handle = conn->connh = iscsi_handle(conn->dd_data);
 
 	spin_lock_irqsave(&connlock, flags);
 	list_add(&conn->conn_list, &connlist);
-	list_add(&conn->session_list, &session->connections);
 	conn->active = 1;
 	spin_unlock_irqrestore(&connlock, flags);
 
 	scsi_host_put(shost);
 	return 0;
 
-out_release_parent_ref:
+free_pdu_pool:
+	mempool_zone_destroy(conn->z_pdu);
+destroy_conn:
+	if (transport->destroy_conn)
+		transport->destroy_conn(conn->dd_data);
+release_ref:
 	scsi_host_put(shost);
-out_destroy_conn:
-	transport->destroy_conn(ev->r.handle);
-out_free_error_pool:
-	mempool_destroy(conn->z_error.pool);
-out_free_pdu_pool:
-	mempool_destroy(conn->z_pdu.pool);
-out_free_conn:
-	kfree(conn);
-out_release_ref:
-	scsi_host_put(shost);
-	return error;
+	return -ENOMEM;
 }
 
 static int
 iscsi_if_destroy_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
 {
 	unsigned long flags;
-	struct iscsi_if_conn *conn;
+	struct iscsi_cls_conn *conn;
+	struct mempool_zone *z_error, *z_pdu;
 
 	conn = iscsi_if_find_conn(ev->u.d_conn.conn_handle);
 	if (!conn)
 		return -EEXIST;
 
-	transport->destroy_conn(ev->u.d_conn.conn_handle);
+	if (!transport->destroy_conn)
+		return -EINVAL;
 
 	spin_lock_irqsave(&connlock, flags);
 	conn->active = 0;
 	list_del(&conn->conn_list);
 	spin_unlock_irqrestore(&connlock, flags);
 
-	transport_unregister_device(&conn->dev);
-	device_unregister(&conn->dev);
-	return 0;
-}
-
-static int
-iscsi_if_get_stats(struct iscsi_transport *transport, struct sk_buff *skb,
-		   struct nlmsghdr *nlh)
-{
-	struct iscsi_uevent *ev = NLMSG_DATA(nlh);
-	struct iscsi_stats *stats;
-	struct sk_buff *skbstat;
-	struct iscsi_if_conn *conn;
-	struct nlmsghdr	*nlhstat;
-	struct iscsi_uevent *evstat;
-	int len = NLMSG_SPACE(sizeof(*ev) +
-			      sizeof(struct iscsi_stats) +
-			      sizeof(struct iscsi_stats_custom) *
-			      ISCSI_STATS_CUSTOM_MAX);
-	int err = 0;
-
-	conn = iscsi_if_find_conn(ev->u.get_stats.conn_handle);
-	if (!conn)
-		return -EEXIST;
-
-	do {
-		int actual_size;
-
-		mempool_zone_complete(&conn->z_pdu);
-
-		skbstat = mempool_zone_get_skb(&conn->z_pdu);
-		if (!skbstat) {
-			printk(KERN_ERR "iscsi%d: can not deliver stats: OOM\n",
-			       conn->host->host_no);
-			return -ENOMEM;
-		}
-
-		nlhstat = __nlmsg_put(skbstat, daemon_pid, 0, 0,
-				      (len - sizeof(*nlhstat)), 0);
-		evstat = NLMSG_DATA(nlhstat);
-		memset(evstat, 0, sizeof(*evstat));
-		evstat->transport_handle = iscsi_handle(conn->transport);
-		evstat->type = nlh->nlmsg_type;
-		if (atomic_read(&conn->z_pdu.allocated) >= conn->z_pdu.hiwat)
-			evstat->iferror = -ENOMEM;
-		evstat->u.get_stats.conn_handle =
-			ev->u.get_stats.conn_handle;
-		stats = (struct iscsi_stats *)
-			((char*)evstat + sizeof(*evstat));
-		memset(stats, 0, sizeof(*stats));
+	z_pdu = conn->z_pdu;
+	z_error = conn->z_error;
 
-		transport->get_stats(ev->u.get_stats.conn_handle, stats);
-		actual_size = NLMSG_SPACE(sizeof(struct iscsi_uevent) +
-					  sizeof(struct iscsi_stats) +
-					  sizeof(struct iscsi_stats_custom) *
-					  stats->custom_length);
-		actual_size -= sizeof(*nlhstat);
-		actual_size = NLMSG_LENGTH(actual_size);
-		skb_trim(skb, NLMSG_ALIGN(actual_size));
-		nlhstat->nlmsg_len = actual_size;
+	if (transport->destroy_conn)
+		transport->destroy_conn(conn);
 
-		err = iscsi_unicast_skb(&conn->z_pdu, skbstat);
-	} while (err < 0 && err != -ECONNREFUSED);
+	mempool_zone_destroy(z_pdu);
+	mempool_zone_destroy(z_error);
 
-	return err;
+	return 0;
 }
 
 static int
@@ -881,7 +938,7 @@ iscsi_if_rx(struct sock *sk, int len)
 {
 	struct sk_buff *skb;
 
-	down(&rx_queue_sema);
+	mutex_lock(&rx_queue_mutex);
 	while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
 		while (skb->len >= NLMSG_SPACE(0)) {
 			int err;
@@ -915,17 +972,20 @@ iscsi_if_rx(struct sock *sk, int len)
 				err = iscsi_if_send_reply(
 					NETLINK_CREDS(skb)->pid, nlh->nlmsg_seq,
 					nlh->nlmsg_type, 0, 0, ev, sizeof(*ev));
-				if (atomic_read(&z_reply.allocated) >=
-						z_reply.hiwat)
+				if (atomic_read(&z_reply->allocated) >=
+						z_reply->hiwat)
 					ev->iferror = -ENOMEM;
 			} while (err < 0 && err != -ECONNREFUSED);
 			skb_pull(skb, rlen);
 		}
 		kfree_skb(skb);
 	}
-	up(&rx_queue_sema);
+	mutex_unlock(&rx_queue_mutex);
 }
 
+#define iscsi_cdev_to_conn(_cdev) \
+	iscsi_dev_to_conn(_cdev->dev)
+
 /*
  * iSCSI connection attrs
  */
@@ -934,12 +994,10 @@ static ssize_t								\
 show_conn_int_param_##param(struct class_device *cdev, char *buf)	\
 {									\
 	uint32_t value = 0;						\
-	struct iscsi_if_conn *conn = iscsi_cdev_to_if_conn(cdev);	\
-	struct iscsi_internal *priv;					\
+	struct iscsi_cls_conn *conn = iscsi_cdev_to_conn(cdev);		\
+	struct iscsi_transport *t = conn->transport;			\
 									\
-	priv = to_iscsi_internal(conn->host->transportt);		\
-	if (priv->param_mask & (1 << param))				\
-		priv->iscsi_transport->get_param(conn->connh, param, &value); \
+	t->get_conn_param(conn->dd_data, param, &value);		\
 	return snprintf(buf, 20, format"\n", value);			\
 }
 
@@ -954,6 +1012,9 @@ iscsi_conn_int_attr(data_digest, ISCSI_PARAM_DATADGST_EN, "%d");
 iscsi_conn_int_attr(ifmarker, ISCSI_PARAM_IFMARKER_EN, "%d");
 iscsi_conn_int_attr(ofmarker, ISCSI_PARAM_OFMARKER_EN, "%d");
 
+#define iscsi_cdev_to_session(_cdev) \
+	iscsi_dev_to_session(_cdev->dev)
+
 /*
  * iSCSI session attrs
  */
@@ -962,20 +1023,11 @@ static ssize_t								\
 show_session_int_param_##param(struct class_device *cdev, char *buf)	\
 {									\
 	uint32_t value = 0;						\
-	struct iscsi_if_session *session = iscsi_cdev_to_if_session(cdev); \
-	struct Scsi_Host *shost = iscsi_if_session_to_shost(session);	\
-	struct iscsi_internal *priv = to_iscsi_internal(shost->transportt); \
-	struct iscsi_if_conn *conn = NULL;				\
-	unsigned long  flags;						\
-									\
-	spin_lock_irqsave(&connlock, flags);				\
-	if (!list_empty(&session->connections))				\
-		conn = list_entry(session->connections.next,		\
-				  struct iscsi_if_conn, session_list);	\
-	spin_unlock_irqrestore(&connlock, flags);			\
+	struct iscsi_cls_session *session = iscsi_cdev_to_session(cdev);	\
+	struct Scsi_Host *shost = iscsi_session_to_shost(session);	\
+	struct iscsi_transport *t = session->transport;			\
 									\
-	if (conn && (priv->param_mask & (1 << param)))			\
-		priv->iscsi_transport->get_param(conn->connh, param, &value);\
+	t->get_session_param(shost, param, &value);			\
 	return snprintf(buf, 20, format"\n", value);			\
 }
 
@@ -1004,23 +1056,18 @@ iscsi_session_int_attr(erl, ISCSI_PARAM_ERL, "%d");
 		count++;						\
 	}
 
-static int iscsi_is_session_dev(const struct device *dev)
-{
-	return dev->release == iscsi_if_session_dev_release;
-}
-
 static int iscsi_session_match(struct attribute_container *cont,
 			   struct device *dev)
 {
-	struct iscsi_if_session *session;
+	struct iscsi_cls_session *session;
 	struct Scsi_Host *shost;
 	struct iscsi_internal *priv;
 
 	if (!iscsi_is_session_dev(dev))
 		return 0;
 
-	session = iscsi_dev_to_if_session(dev);
-	shost = iscsi_if_session_to_shost(session);
+	session = iscsi_dev_to_session(dev);
+	shost = iscsi_session_to_shost(session);
 	if (!shost->transportt)
 		return 0;
 
@@ -1031,23 +1078,21 @@ static int iscsi_session_match(struct attribute_container *cont,
 	return &priv->session_cont.ac == cont;
 }
 
-static int iscsi_is_conn_dev(const struct device *dev)
-{
-	return dev->release == iscsi_if_conn_dev_release;
-}
-
 static int iscsi_conn_match(struct attribute_container *cont,
 			   struct device *dev)
 {
-	struct iscsi_if_conn *conn;
+	struct iscsi_cls_session *session;
+	struct iscsi_cls_conn *conn;
 	struct Scsi_Host *shost;
 	struct iscsi_internal *priv;
 
 	if (!iscsi_is_conn_dev(dev))
 		return 0;
 
-	conn = iscsi_dev_to_if_conn(dev);
-	shost = conn->host;
+	conn = iscsi_dev_to_conn(dev);
+	session = iscsi_dev_to_session(conn->dev.parent);
+	shost = iscsi_session_to_shost(session);
+
 	if (!shost->transportt)
 		return 0;
 
@@ -1058,7 +1103,8 @@ static int iscsi_conn_match(struct attribute_container *cont,
 	return &priv->conn_cont.ac == cont;
 }
 
-int iscsi_register_transport(struct iscsi_transport *tt)
+struct scsi_transport_template *
+iscsi_register_transport(struct iscsi_transport *tt)
 {
 	struct iscsi_internal *priv;
 	unsigned long flags;
@@ -1068,15 +1114,14 @@ int iscsi_register_transport(struct iscsi_transport *tt)
 
 	priv = iscsi_if_transport_lookup(tt);
 	if (priv)
-		return -EEXIST;
+		return NULL;
 
 	priv = kmalloc(sizeof(*priv), GFP_KERNEL);
 	if (!priv)
-		return -ENOMEM;
+		return NULL;
 	memset(priv, 0, sizeof(*priv));
 	INIT_LIST_HEAD(&priv->list);
 	INIT_LIST_HEAD(&priv->sessions);
-	spin_lock_init(&priv->session_lock);
 	priv->iscsi_transport = tt;
 
 	priv->cdev.class = &iscsi_transport_class;
@@ -1142,13 +1187,13 @@ int iscsi_register_transport(struct iscsi_transport *tt)
 	spin_unlock_irqrestore(&iscsi_transport_lock, flags);
 
 	printk(KERN_NOTICE "iscsi: registered transport (%s)\n", tt->name);
-	return 0;
+	return &priv->t;
 
 unregister_cdev:
 	class_device_unregister(&priv->cdev);
 free_priv:
 	kfree(priv);
-	return err;
+	return NULL;
 }
 EXPORT_SYMBOL_GPL(iscsi_register_transport);
 
@@ -1159,19 +1204,11 @@ int iscsi_unregister_transport(struct iscsi_transport *tt)
 
 	BUG_ON(!tt);
 
-	down(&rx_queue_sema);
+	mutex_lock(&rx_queue_mutex);
 
 	priv = iscsi_if_transport_lookup(tt);
 	BUG_ON (!priv);
 
-	spin_lock_irqsave(&priv->session_lock, flags);
-	if (!list_empty(&priv->sessions)) {
-		spin_unlock_irqrestore(&priv->session_lock, flags);
-		up(&rx_queue_sema);
-		return -EPERM;
-	}
-	spin_unlock_irqrestore(&priv->session_lock, flags);
-
 	spin_lock_irqsave(&iscsi_transport_lock, flags);
 	list_del(&priv->list);
 	spin_unlock_irqrestore(&iscsi_transport_lock, flags);
@@ -1181,7 +1218,7 @@ int iscsi_unregister_transport(struct iscsi_transport *tt)
 
 	sysfs_remove_group(&priv->cdev.kobj, &iscsi_transport_group);
 	class_device_unregister(&priv->cdev);
-	up(&rx_queue_sema);
+	mutex_unlock(&rx_queue_mutex);
 
 	return 0;
 }
@@ -1194,14 +1231,14 @@ iscsi_rcv_nl_event(struct notifier_block *this, unsigned long event, void *ptr)
 
 	if (event == NETLINK_URELEASE &&
 	    n->protocol == NETLINK_ISCSI && n->pid) {
-		struct iscsi_if_conn *conn;
+		struct iscsi_cls_conn *conn;
 		unsigned long flags;
 
-		mempool_zone_complete(&z_reply);
+		mempool_zone_complete(z_reply);
 		spin_lock_irqsave(&connlock, flags);
 		list_for_each_entry(conn, &connlist, conn_list) {
-			mempool_zone_complete(&conn->z_error);
-			mempool_zone_complete(&conn->z_pdu);
+			mempool_zone_complete(conn->z_error);
+			mempool_zone_complete(conn->z_pdu);
 		}
 		spin_unlock_irqrestore(&connlock, flags);
 	}
@@ -1234,15 +1271,15 @@ static __init int iscsi_transport_init(void)
 		goto unregister_session_class;
 
 	nls = netlink_kernel_create(NETLINK_ISCSI, 1, iscsi_if_rx,
-				    THIS_MODULE);
+			THIS_MODULE);
 	if (!nls) {
 		err = -ENOBUFS;
 		goto unregister_notifier;
 	}
 
-	err = mempool_zone_init(&z_reply, Z_MAX_REPLY,
+	z_reply = mempool_zone_init(Z_MAX_REPLY,
 		NLMSG_SPACE(sizeof(struct iscsi_uevent)), Z_HIWAT_REPLY);
-	if (!err)
+	if (z_reply)
 		return 0;
 
 	sock_release(nls->sk_socket);
@@ -1259,7 +1296,7 @@ unregister_transport_class:
 
 static void __exit iscsi_transport_exit(void)
 {
-	mempool_destroy(z_reply.pool);
+	mempool_zone_destroy(z_reply);
 	sock_release(nls->sk_socket);
 	netlink_unregister_notifier(&iscsi_nl_notifier);
 	transport_class_unregister(&iscsi_connection_class);