IB/iser: iSCSI iSER transport provider high level code

This file contains the code that registeres with the iscsi transport manager
and with the SCSI Mid Layer, where much of the provided functions to iSCSI and
SCSI are implemented in libiscsi.

Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 790 insertions, 0 deletions

diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.c b/drivers/infiniband/ulp/iser/iscsi_iser.c
new file mode 100644
index 00000000000..4c3f2de2a06
--- /dev/null
+++ b/drivers/infiniband/ulp/iser/iscsi_iser.c
@@ -0,0 +1,790 @@
+/*
+ * iSCSI Initiator over iSER Data-Path
+ *
+ * Copyright (C) 2004 Dmitry Yusupov
+ * Copyright (C) 2004 Alex Aizman
+ * Copyright (C) 2005 Mike Christie
+ * Copyright (c) 2005, 2006 Voltaire, Inc. All rights reserved.
+ * maintained by openib-general@openib.org
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *	- Redistributions of source code must retain the above
+ *	  copyright notice, this list of conditions and the following
+ *	  disclaimer.
+ *
+ *	- Redistributions in binary form must reproduce the above
+ *	  copyright notice, this list of conditions and the following
+ *	  disclaimer in the documentation and/or other materials
+ *	  provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * Credits:
+ *	Christoph Hellwig
+ *	FUJITA Tomonori
+ *	Arne Redlich
+ *	Zhenyu Wang
+ * Modified by:
+ *      Erez Zilber
+ *
+ *
+ * $Id: iscsi_iser.c 6965 2006-05-07 11:36:20Z ogerlitz $
+ */
+
+#include <linux/types.h>
+#include <linux/list.h>
+#include <linux/hardirq.h>
+#include <linux/kfifo.h>
+#include <linux/blkdev.h>
+#include <linux/init.h>
+#include <linux/ioctl.h>
+#include <linux/devfs_fs_kernel.h>
+#include <linux/cdev.h>
+#include <linux/in.h>
+#include <linux/net.h>
+#include <linux/scatterlist.h>
+#include <linux/delay.h>
+
+#include <net/sock.h>
+
+#include <asm/uaccess.h>
+
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_tcq.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_transport_iscsi.h>
+
+#include "iscsi_iser.h"
+
+static unsigned int iscsi_max_lun = 512;
+module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO);
+
+int iser_debug_level = 0;
+
+MODULE_DESCRIPTION("iSER (iSCSI Extensions for RDMA) Datamover "
+		   "v" DRV_VER " (" DRV_DATE ")");
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_AUTHOR("Alex Nezhinsky, Dan Bar Dov, Or Gerlitz");
+
+module_param_named(debug_level, iser_debug_level, int, 0644);
+MODULE_PARM_DESC(debug_level, "Enable debug tracing if > 0 (default:disabled)");
+
+struct iser_global ig;
+
+void
+iscsi_iser_recv(struct iscsi_conn *conn,
+		struct iscsi_hdr *hdr, char *rx_data, int rx_data_len)
+{
+	int rc = 0;
+	uint32_t ret_itt;
+	int datalen;
+	int ahslen;
+
+	/* verify PDU length */
+	datalen = ntoh24(hdr->dlength);
+	if (datalen != rx_data_len) {
+		printk(KERN_ERR "iscsi_iser: datalen %d (hdr) != %d (IB) \n",
+		       datalen, rx_data_len);
+		rc = ISCSI_ERR_DATALEN;
+		goto error;
+	}
+
+	/* read AHS */
+	ahslen = hdr->hlength * 4;
+
+	/* verify itt (itt encoding: age+cid+itt) */
+	rc = iscsi_verify_itt(conn, hdr, &ret_itt);
+
+	if (!rc)
+		rc = iscsi_complete_pdu(conn, hdr, rx_data, rx_data_len);
+
+	if (rc && rc != ISCSI_ERR_NO_SCSI_CMD)
+		goto error;
+
+	return;
+error:
+	iscsi_conn_failure(conn, rc);
+}
+
+
+/**
+ * iscsi_iser_cmd_init - Initialize iSCSI SCSI_READ or SCSI_WRITE commands
+ *
+ **/
+static void
+iscsi_iser_cmd_init(struct iscsi_cmd_task *ctask)
+{
+	struct iscsi_iser_conn     *iser_conn  = ctask->conn->dd_data;
+	struct iscsi_iser_cmd_task *iser_ctask = ctask->dd_data;
+	struct scsi_cmnd  *sc = ctask->sc;
+
+	iser_ctask->command_sent = 0;
+	iser_ctask->iser_conn    = iser_conn;
+
+	if (sc->sc_data_direction == DMA_TO_DEVICE) {
+		BUG_ON(ctask->total_length == 0);
+		/* bytes to be sent via RDMA operations */
+		iser_ctask->rdma_data_count = ctask->total_length -
+					 ctask->imm_count -
+					 ctask->unsol_count;
+
+		debug_scsi("cmd [itt %x total %d imm %d unsol_data %d "
+			   "rdma_data %d]\n",
+			   ctask->itt, ctask->total_length, ctask->imm_count,
+			   ctask->unsol_count, iser_ctask->rdma_data_count);
+	} else
+		/* bytes to be sent via RDMA operations */
+		iser_ctask->rdma_data_count = ctask->total_length;
+
+	iser_ctask_rdma_init(iser_ctask);
+}
+
+/**
+ * iscsi_mtask_xmit - xmit management(immediate) task
+ * @conn: iscsi connection
+ * @mtask: task management task
+ *
+ * Notes:
+ *	The function can return -EAGAIN in which case caller must
+ *	call it again later, or recover. '0' return code means successful
+ *	xmit.
+ *
+ **/
+static int
+iscsi_iser_mtask_xmit(struct iscsi_conn *conn,
+		      struct iscsi_mgmt_task *mtask)
+{
+	int error = 0;
+
+	debug_scsi("mtask deq [cid %d itt 0x%x]\n", conn->id, mtask->itt);
+
+	error = iser_send_control(conn, mtask);
+
+	/* since iser xmits control with zero copy, mtasks can not be recycled
+	 * right after sending them.
+	 * The recycling scheme is based on whether a response is expected
+	 * - if yes, the mtask is recycled at iscsi_complete_pdu
+	 * - if no,  the mtask is recycled at iser_snd_completion
+	 */
+	if (error && error != -EAGAIN)
+		iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
+
+	return error;
+}
+
+static int
+iscsi_iser_ctask_xmit_unsol_data(struct iscsi_conn *conn,
+				 struct iscsi_cmd_task *ctask)
+{
+	struct iscsi_data  hdr;
+	int error = 0;
+	struct iscsi_iser_cmd_task *iser_ctask = ctask->dd_data;
+
+	/* Send data-out PDUs while there's still unsolicited data to send */
+	while (ctask->unsol_count > 0) {
+		iscsi_prep_unsolicit_data_pdu(ctask, &hdr,
+					      iser_ctask->rdma_data_count);
+
+		debug_scsi("Sending data-out: itt 0x%x, data count %d\n",
+			   hdr.itt, ctask->data_count);
+
+		/* the buffer description has been passed with the command */
+		/* Send the command */
+		error = iser_send_data_out(conn, ctask, &hdr);
+		if (error) {
+			ctask->unsol_datasn--;
+			goto iscsi_iser_ctask_xmit_unsol_data_exit;
+		}
+		ctask->unsol_count -= ctask->data_count;
+		debug_scsi("Need to send %d more as data-out PDUs\n",
+			   ctask->unsol_count);
+	}
+
+iscsi_iser_ctask_xmit_unsol_data_exit:
+	return error;
+}
+
+static int
+iscsi_iser_ctask_xmit(struct iscsi_conn *conn,
+		      struct iscsi_cmd_task *ctask)
+{
+	struct iscsi_iser_cmd_task *iser_ctask = ctask->dd_data;
+	int error = 0;
+
+	debug_scsi("ctask deq [cid %d itt 0x%x]\n",
+		   conn->id, ctask->itt);
+
+	/*
+	 * serialize with TMF AbortTask
+	 */
+	if (ctask->mtask)
+		return error;
+
+	/* Send the cmd PDU */
+	if (!iser_ctask->command_sent) {
+		error = iser_send_command(conn, ctask);
+		if (error)
+			goto iscsi_iser_ctask_xmit_exit;
+		iser_ctask->command_sent = 1;
+	}
+
+	/* Send unsolicited data-out PDU(s) if necessary */
+	if (ctask->unsol_count)
+		error = iscsi_iser_ctask_xmit_unsol_data(conn, ctask);
+
+ iscsi_iser_ctask_xmit_exit:
+	if (error && error != -EAGAIN)
+		iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
+	return error;
+}
+
+static void
+iscsi_iser_cleanup_ctask(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
+{
+	struct iscsi_iser_cmd_task *iser_ctask = ctask->dd_data;
+
+	if (iser_ctask->status == ISER_TASK_STATUS_STARTED) {
+		iser_ctask->status = ISER_TASK_STATUS_COMPLETED;
+		iser_ctask_rdma_finalize(iser_ctask);
+	}
+}
+
+static struct iser_conn *
+iscsi_iser_ib_conn_lookup(__u64 ep_handle)
+{
+	struct iser_conn *ib_conn;
+	struct iser_conn *uib_conn = (struct iser_conn *)(unsigned long)ep_handle;
+
+	mutex_lock(&ig.connlist_mutex);
+	list_for_each_entry(ib_conn, &ig.connlist, conn_list) {
+		if (ib_conn == uib_conn) {
+			mutex_unlock(&ig.connlist_mutex);
+			return ib_conn;
+		}
+	}
+	mutex_unlock(&ig.connlist_mutex);
+	iser_err("no conn exists for eph %llx\n",(unsigned long long)ep_handle);
+	return NULL;
+}
+
+static struct iscsi_cls_conn *
+iscsi_iser_conn_create(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
+{
+	struct iscsi_conn *conn;
+	struct iscsi_cls_conn *cls_conn;
+	struct iscsi_iser_conn *iser_conn;
+
+	cls_conn = iscsi_conn_setup(cls_session, conn_idx);
+	if (!cls_conn)
+		return NULL;
+	conn = cls_conn->dd_data;
+
+	/*
+	 * due to issues with the login code re iser sematics
+	 * this not set in iscsi_conn_setup - FIXME
+	 */
+	conn->max_recv_dlength = 128;
+
+	iser_conn = kzalloc(sizeof(*iser_conn), GFP_KERNEL);
+	if (!iser_conn)
+		goto conn_alloc_fail;
+
+	/* currently this is the only field which need to be initiated */
+	rwlock_init(&iser_conn->lock);
+
+	conn->dd_data = iser_conn;
+	iser_conn->iscsi_conn = conn;
+
+	return cls_conn;
+
+conn_alloc_fail:
+	iscsi_conn_teardown(cls_conn);
+	return NULL;
+}
+
+static void
+iscsi_iser_conn_destroy(struct iscsi_cls_conn *cls_conn)
+{
+	struct iscsi_conn *conn = cls_conn->dd_data;
+	struct iscsi_iser_conn *iser_conn = conn->dd_data;
+
+	iscsi_conn_teardown(cls_conn);
+	kfree(iser_conn);
+}
+
+static int
+iscsi_iser_conn_bind(struct iscsi_cls_session *cls_session,
+		     struct iscsi_cls_conn *cls_conn, uint64_t transport_eph,
+		     int is_leading)
+{
+	struct iscsi_conn *conn = cls_conn->dd_data;
+	struct iscsi_iser_conn *iser_conn;
+	struct iser_conn *ib_conn;
+	int error;
+
+	error = iscsi_conn_bind(cls_session, cls_conn, is_leading);
+	if (error)
+		return error;
+
+	/* the transport ep handle comes from user space so it must be
+	 * verified against the global ib connections list */
+	ib_conn = iscsi_iser_ib_conn_lookup(transport_eph);
+	if (!ib_conn) {
+		iser_err("can't bind eph %llx\n",
+			 (unsigned long long)transport_eph);
+		return -EINVAL;
+	}
+	/* binds the iSER connection retrieved from the previously
+	 * connected ep_handle to the iSCSI layer connection. exchanges
+	 * connection pointers */
+	iser_err("binding iscsi conn %p to iser_conn %p\n",conn,ib_conn);
+	iser_conn = conn->dd_data;
+	ib_conn->iser_conn = iser_conn;
+	iser_conn->ib_conn  = ib_conn;
+
+	conn->recv_lock = &iser_conn->lock;
+
+	return 0;
+}
+
+static int
+iscsi_iser_conn_start(struct iscsi_cls_conn *cls_conn)
+{
+	struct iscsi_conn *conn = cls_conn->dd_data;
+	int err;
+
+	err = iscsi_conn_start(cls_conn);
+	if (err)
+		return err;
+
+	return iser_conn_set_full_featured_mode(conn);
+}
+
+static void
+iscsi_iser_conn_terminate(struct iscsi_conn *conn)
+{
+	struct iscsi_iser_conn *iser_conn = conn->dd_data;
+	struct iser_conn *ib_conn = iser_conn->ib_conn;
+
+	BUG_ON(!ib_conn);
+	/* starts conn teardown process, waits until all previously   *
+	 * posted buffers get flushed, deallocates all conn resources */
+	iser_conn_terminate(ib_conn);
+	iser_conn->ib_conn = NULL;
+	conn->recv_lock = NULL;
+}
+
+
+static struct iscsi_transport iscsi_iser_transport;
+
+static struct iscsi_cls_session *
+iscsi_iser_session_create(struct iscsi_transport *iscsit,
+			 struct scsi_transport_template *scsit,
+			  uint32_t initial_cmdsn, uint32_t *hostno)
+{
+	struct iscsi_cls_session *cls_session;
+	struct iscsi_session *session;
+	int i;
+	uint32_t hn;
+	struct iscsi_cmd_task  *ctask;
+	struct iscsi_mgmt_task *mtask;
+	struct iscsi_iser_cmd_task *iser_ctask;
+	struct iser_desc *desc;
+
+	cls_session = iscsi_session_setup(iscsit, scsit,
+					  sizeof(struct iscsi_iser_cmd_task),
+					  sizeof(struct iser_desc),
+					  initial_cmdsn, &hn);
+	if (!cls_session)
+	return NULL;
+
+	*hostno = hn;
+	session = class_to_transport_session(cls_session);
+
+	/* libiscsi setup itts, data and pool so just set desc fields */
+	for (i = 0; i < session->cmds_max; i++) {
+		ctask      = session->cmds[i];
+		iser_ctask = ctask->dd_data;
+		ctask->hdr = (struct iscsi_cmd *)&iser_ctask->desc.iscsi_header;
+	}
+
+	for (i = 0; i < session->mgmtpool_max; i++) {
+		mtask      = session->mgmt_cmds[i];
+		desc       = mtask->dd_data;
+		mtask->hdr = &desc->iscsi_header;
+		desc->data = mtask->data;
+	}
+
+	return cls_session;
+}
+
+static int
+iscsi_iser_conn_set_param(struct iscsi_cls_conn *cls_conn,
+			  enum iscsi_param param, uint32_t value)
+{
+	struct iscsi_conn *conn = cls_conn->dd_data;
+	struct iscsi_session *session = conn->session;
+
+	spin_lock_bh(&session->lock);
+	if (conn->c_stage != ISCSI_CONN_INITIAL_STAGE &&
+	    conn->stop_stage != STOP_CONN_RECOVER) {
+		printk(KERN_ERR "iscsi_iser: can not change parameter [%d]\n",
+		       param);
+		spin_unlock_bh(&session->lock);
+		return 0;
+	}
+	spin_unlock_bh(&session->lock);
+
+	switch (param) {
+	case ISCSI_PARAM_MAX_RECV_DLENGTH:
+		/* TBD */
+		break;
+	case ISCSI_PARAM_MAX_XMIT_DLENGTH:
+		conn->max_xmit_dlength =  value;
+		break;
+	case ISCSI_PARAM_HDRDGST_EN:
+		if (value) {
+			printk(KERN_ERR "DataDigest wasn't negotiated to None");
+			return -EPROTO;
+		}
+		break;
+	case ISCSI_PARAM_DATADGST_EN:
+		if (value) {
+			printk(KERN_ERR "DataDigest wasn't negotiated to None");
+			return -EPROTO;
+		}
+		break;
+	case ISCSI_PARAM_INITIAL_R2T_EN:
+		session->initial_r2t_en = value;
+		break;
+	case ISCSI_PARAM_IMM_DATA_EN:
+		session->imm_data_en = value;
+		break;
+	case ISCSI_PARAM_FIRST_BURST:
+		session->first_burst = value;
+		break;
+	case ISCSI_PARAM_MAX_BURST:
+		session->max_burst = value;
+		break;
+	case ISCSI_PARAM_PDU_INORDER_EN:
+		session->pdu_inorder_en = value;
+		break;
+	case ISCSI_PARAM_DATASEQ_INORDER_EN:
+		session->dataseq_inorder_en = value;
+		break;
+	case ISCSI_PARAM_ERL:
+		session->erl = value;
+		break;
+	case ISCSI_PARAM_IFMARKER_EN:
+		if (value) {
+			printk(KERN_ERR "IFMarker wasn't negotiated to No");
+			return -EPROTO;
+		}
+		break;
+	case ISCSI_PARAM_OFMARKER_EN:
+		if (value) {
+			printk(KERN_ERR "OFMarker wasn't negotiated to No");
+			return -EPROTO;
+		}
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static int
+iscsi_iser_session_get_param(struct iscsi_cls_session *cls_session,
+			     enum iscsi_param param, uint32_t *value)
+{
+	struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
+	struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
+
+	switch (param) {
+	case ISCSI_PARAM_INITIAL_R2T_EN:
+		*value = session->initial_r2t_en;
+		break;
+	case ISCSI_PARAM_MAX_R2T:
+		*value = session->max_r2t;
+		break;
+	case ISCSI_PARAM_IMM_DATA_EN:
+		*value = session->imm_data_en;
+		break;
+	case ISCSI_PARAM_FIRST_BURST:
+		*value = session->first_burst;
+		break;
+	case ISCSI_PARAM_MAX_BURST:
+		*value = session->max_burst;
+		break;
+	case ISCSI_PARAM_PDU_INORDER_EN:
+		*value = session->pdu_inorder_en;
+		break;
+	case ISCSI_PARAM_DATASEQ_INORDER_EN:
+		*value = session->dataseq_inorder_en;
+		break;
+	case ISCSI_PARAM_ERL:
+		*value = session->erl;
+		break;
+	case ISCSI_PARAM_IFMARKER_EN:
+		*value = 0;
+		break;
+	case ISCSI_PARAM_OFMARKER_EN:
+		*value = 0;
+		break;
+	default:
+		return ISCSI_ERR_PARAM_NOT_FOUND;
+	}
+
+	return 0;
+}
+
+static int
+iscsi_iser_conn_get_param(struct iscsi_cls_conn *cls_conn,
+			  enum iscsi_param param, uint32_t *value)
+{
+	struct iscsi_conn *conn = cls_conn->dd_data;
+
+	switch(param) {
+	case ISCSI_PARAM_MAX_RECV_DLENGTH:
+		*value = conn->max_recv_dlength;
+		break;
+	case ISCSI_PARAM_MAX_XMIT_DLENGTH:
+		*value = conn->max_xmit_dlength;
+		break;
+	case ISCSI_PARAM_HDRDGST_EN:
+		*value = 0;
+		break;
+	case ISCSI_PARAM_DATADGST_EN:
+		*value = 0;
+		break;
+	/*case ISCSI_PARAM_TARGET_RECV_DLENGTH:
+		*value = conn->target_recv_dlength;
+		break;
+	case ISCSI_PARAM_INITIATOR_RECV_DLENGTH:
+		*value = conn->initiator_recv_dlength;
+		break;*/
+	default:
+		return ISCSI_ERR_PARAM_NOT_FOUND;
+	}
+
+	return 0;
+}
+
+
+static void
+iscsi_iser_conn_get_stats(struct iscsi_cls_conn *cls_conn, struct iscsi_stats *stats)
+{
+	struct iscsi_conn *conn = cls_conn->dd_data;
+
+	stats->txdata_octets = conn->txdata_octets;
+	stats->rxdata_octets = conn->rxdata_octets;
+	stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
+	stats->dataout_pdus = conn->dataout_pdus_cnt;
+	stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
+	stats->datain_pdus = conn->datain_pdus_cnt; /* always 0 */
+	stats->r2t_pdus = conn->r2t_pdus_cnt; /* always 0 */
+	stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
+	stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
+	stats->custom_length = 3;
+	strcpy(stats->custom[0].desc, "qp_tx_queue_full");
+	stats->custom[0].value = 0; /* TB iser_conn->qp_tx_queue_full; */
+	strcpy(stats->custom[1].desc, "fmr_map_not_avail");
+	stats->custom[1].value = 0; /* TB iser_conn->fmr_map_not_avail */;
+	strcpy(stats->custom[2].desc, "eh_abort_cnt");
+	stats->custom[2].value = conn->eh_abort_cnt;
+}
+
+static int
+iscsi_iser_ep_connect(struct sockaddr *dst_addr, int non_blocking,
+		      __u64 *ep_handle)
+{
+	int err;
+	struct iser_conn *ib_conn;
+
+	err = iser_conn_init(&ib_conn);
+	if (err)
+		goto out;
+
+	err = iser_connect(ib_conn, NULL, (struct sockaddr_in *)dst_addr, non_blocking);
+	if (!err)
+		*ep_handle = (__u64)(unsigned long)ib_conn;
+
+out:
+	return err;
+}
+
+static int
+iscsi_iser_ep_poll(__u64 ep_handle, int timeout_ms)
+{
+	struct iser_conn *ib_conn = iscsi_iser_ib_conn_lookup(ep_handle);
+	int rc;
+
+	if (!ib_conn)
+		return -EINVAL;
+
+	rc = wait_event_interruptible_timeout(ib_conn->wait,
+			     ib_conn->state == ISER_CONN_UP,
+			     msecs_to_jiffies(timeout_ms));
+
+	/* if conn establishment failed, return error code to iscsi */
+	if (!rc &&
+	    (ib_conn->state == ISER_CONN_TERMINATING ||
+	     ib_conn->state == ISER_CONN_DOWN))
+		rc = -1;
+
+	iser_err("ib conn %p rc = %d\n", ib_conn, rc);
+
+	if (rc > 0)
+		return 1; /* success, this is the equivalent of POLLOUT */
+	else if (!rc)
+		return 0; /* timeout */
+	else
+		return rc; /* signal */
+}
+
+static void
+iscsi_iser_ep_disconnect(__u64 ep_handle)
+{
+	struct iser_conn *ib_conn = iscsi_iser_ib_conn_lookup(ep_handle);
+
+	if (!ib_conn)
+		return;
+
+	iser_err("ib conn %p state %d\n",ib_conn, ib_conn->state);
+
+	iser_conn_terminate(ib_conn);
+}
+
+static struct scsi_host_template iscsi_iser_sht = {
+	.name                   = "iSCSI Initiator over iSER, v." DRV_VER,
+	.queuecommand           = iscsi_queuecommand,
+	.can_queue		= ISCSI_XMIT_CMDS_MAX - 1,
+	.sg_tablesize           = ISCSI_ISER_SG_TABLESIZE,
+	.cmd_per_lun            = ISCSI_MAX_CMD_PER_LUN,
+	.eh_abort_handler       = iscsi_eh_abort,
+	.eh_host_reset_handler	= iscsi_eh_host_reset,
+	.use_clustering         = DISABLE_CLUSTERING,
+	.proc_name              = "iscsi_iser",
+	.this_id                = -1,
+};
+
+static struct iscsi_transport iscsi_iser_transport = {
+	.owner                  = THIS_MODULE,
+	.name                   = "iser",
+	.caps                   = CAP_RECOVERY_L0 | CAP_MULTI_R2T,
+	.param_mask		= ISCSI_MAX_RECV_DLENGTH |
+				  ISCSI_MAX_XMIT_DLENGTH |
+				  ISCSI_HDRDGST_EN |
+				  ISCSI_DATADGST_EN |
+				  ISCSI_INITIAL_R2T_EN |
+				  ISCSI_MAX_R2T |
+				  ISCSI_IMM_DATA_EN |
+				  ISCSI_FIRST_BURST |
+				  ISCSI_MAX_BURST |
+				  ISCSI_PDU_INORDER_EN |
+				  ISCSI_DATASEQ_INORDER_EN,
+	.host_template          = &iscsi_iser_sht,
+	.conndata_size		= sizeof(struct iscsi_conn),
+	.max_lun                = ISCSI_ISER_MAX_LUN,
+	.max_cmd_len            = ISCSI_ISER_MAX_CMD_LEN,
+	/* session management */
+	.create_session         = iscsi_iser_session_create,
+	.destroy_session        = iscsi_session_teardown,
+	/* connection management */
+	.create_conn            = iscsi_iser_conn_create,
+	.bind_conn              = iscsi_iser_conn_bind,
+	.destroy_conn           = iscsi_iser_conn_destroy,
+	.set_param              = iscsi_iser_conn_set_param,
+	.get_conn_param		= iscsi_iser_conn_get_param,
+	.get_session_param	= iscsi_iser_session_get_param,
+	.start_conn             = iscsi_iser_conn_start,
+	.stop_conn              = iscsi_conn_stop,
+	/* these are called as part of conn recovery */
+	.suspend_conn_recv	= NULL, /* FIXME is/how this relvant to iser? */
+	.terminate_conn		= iscsi_iser_conn_terminate,
+	/* IO */
+	.send_pdu		= iscsi_conn_send_pdu,
+	.get_stats		= iscsi_iser_conn_get_stats,
+	.init_cmd_task		= iscsi_iser_cmd_init,
+	.xmit_cmd_task		= iscsi_iser_ctask_xmit,
+	.xmit_mgmt_task		= iscsi_iser_mtask_xmit,
+	.cleanup_cmd_task	= iscsi_iser_cleanup_ctask,
+	/* recovery */
+	.session_recovery_timedout = iscsi_session_recovery_timedout,
+
+	.ep_connect             = iscsi_iser_ep_connect,
+	.ep_poll                = iscsi_iser_ep_poll,
+	.ep_disconnect          = iscsi_iser_ep_disconnect
+};
+
+static int __init iser_init(void)
+{
+	int err;
+
+	iser_dbg("Starting iSER datamover...\n");
+
+	if (iscsi_max_lun < 1) {
+		printk(KERN_ERR "Invalid max_lun value of %u\n", iscsi_max_lun);
+		return -EINVAL;
+	}
+
+	iscsi_iser_transport.max_lun = iscsi_max_lun;
+
+	memset(&ig, 0, sizeof(struct iser_global));
+
+	ig.desc_cache = kmem_cache_create("iser_descriptors",
+					  sizeof (struct iser_desc),
+					  0, SLAB_HWCACHE_ALIGN,
+					  NULL, NULL);
+	if (ig.desc_cache == NULL)
+		return -ENOMEM;
+
+	/* device init is called only after the first addr resolution */
+	mutex_init(&ig.device_list_mutex);
+	INIT_LIST_HEAD(&ig.device_list);
+	mutex_init(&ig.connlist_mutex);
+	INIT_LIST_HEAD(&ig.connlist);
+
+	if (!iscsi_register_transport(&iscsi_iser_transport)) {
+		iser_err("iscsi_register_transport failed\n");
+		err = -EINVAL;
+		goto register_transport_failure;
+	}
+
+	return 0;
+
+register_transport_failure:
+	kmem_cache_destroy(ig.desc_cache);
+
+	return err;
+}
+
+static void __exit iser_exit(void)
+{
+	iser_dbg("Removing iSER datamover...\n");
+	iscsi_unregister_transport(&iscsi_iser_transport);
+	kmem_cache_destroy(ig.desc_cache);
+}
+
+module_init(iser_init);
+module_exit(iser_exit);