Merge branch 'master' of /home/trondmy/kernel/linux-2.6/

Conflicts:

	fs/nfs/inode.c
	fs/super.c

Fix conflicts between patch 'NFS: Split fs/nfs/inode.c' and patch
'VFS: Permit filesystem to override root dentry on mount'

1 files changed, 1702 insertions, 0 deletions

diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
new file mode 100644
index 00000000000..2673a11a949
--- /dev/null
+++ b/drivers/scsi/libiscsi.c
@@ -0,0 +1,1702 @@
+/*
+ * iSCSI lib functions
+ *
+ * Copyright (C) 2006 Red Hat, Inc.  All rights reserved.
+ * Copyright (C) 2004 - 2006 Mike Christie
+ * Copyright (C) 2004 - 2005 Dmitry Yusupov
+ * Copyright (C) 2004 - 2005 Alex Aizman
+ * maintained by open-iscsi@googlegroups.com
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+#include <linux/types.h>
+#include <linux/mutex.h>
+#include <linux/kfifo.h>
+#include <linux/delay.h>
+#include <net/tcp.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/iscsi_proto.h>
+#include <scsi/scsi_transport.h>
+#include <scsi/scsi_transport_iscsi.h>
+#include <scsi/libiscsi.h>
+
+struct iscsi_session *
+class_to_transport_session(struct iscsi_cls_session *cls_session)
+{
+	struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
+	return iscsi_hostdata(shost->hostdata);
+}
+EXPORT_SYMBOL_GPL(class_to_transport_session);
+
+#define INVALID_SN_DELTA	0xffff
+
+int
+iscsi_check_assign_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
+{
+	uint32_t max_cmdsn = be32_to_cpu(hdr->max_cmdsn);
+	uint32_t exp_cmdsn = be32_to_cpu(hdr->exp_cmdsn);
+
+	if (max_cmdsn < exp_cmdsn -1 &&
+	    max_cmdsn > exp_cmdsn - INVALID_SN_DELTA)
+		return ISCSI_ERR_MAX_CMDSN;
+	if (max_cmdsn > session->max_cmdsn ||
+	    max_cmdsn < session->max_cmdsn - INVALID_SN_DELTA)
+		session->max_cmdsn = max_cmdsn;
+	if (exp_cmdsn > session->exp_cmdsn ||
+	    exp_cmdsn < session->exp_cmdsn - INVALID_SN_DELTA)
+		session->exp_cmdsn = exp_cmdsn;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(iscsi_check_assign_cmdsn);
+
+void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *ctask,
+				   struct iscsi_data *hdr,
+				   int transport_data_cnt)
+{
+	struct iscsi_conn *conn = ctask->conn;
+
+	memset(hdr, 0, sizeof(struct iscsi_data));
+	hdr->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
+	hdr->datasn = cpu_to_be32(ctask->unsol_datasn);
+	ctask->unsol_datasn++;
+	hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
+	memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
+
+	hdr->itt = ctask->hdr->itt;
+	hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
+
+	hdr->offset = cpu_to_be32(ctask->total_length -
+				  transport_data_cnt -
+				  ctask->unsol_count);
+
+	if (ctask->unsol_count > conn->max_xmit_dlength) {
+		hton24(hdr->dlength, conn->max_xmit_dlength);
+		ctask->data_count = conn->max_xmit_dlength;
+		hdr->flags = 0;
+	} else {
+		hton24(hdr->dlength, ctask->unsol_count);
+		ctask->data_count = ctask->unsol_count;
+		hdr->flags = ISCSI_FLAG_CMD_FINAL;
+	}
+}
+EXPORT_SYMBOL_GPL(iscsi_prep_unsolicit_data_pdu);
+
+/**
+ * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
+ * @ctask: iscsi cmd task
+ *
+ * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
+ * fields like dlength or final based on how much data it sends
+ */
+static void iscsi_prep_scsi_cmd_pdu(struct iscsi_cmd_task *ctask)
+{
+	struct iscsi_conn *conn = ctask->conn;
+	struct iscsi_session *session = conn->session;
+	struct iscsi_cmd *hdr = ctask->hdr;
+	struct scsi_cmnd *sc = ctask->sc;
+
+        hdr->opcode = ISCSI_OP_SCSI_CMD;
+        hdr->flags = ISCSI_ATTR_SIMPLE;
+        int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
+        hdr->itt = ctask->itt | (conn->id << ISCSI_CID_SHIFT) |
+                         (session->age << ISCSI_AGE_SHIFT);
+        hdr->data_length = cpu_to_be32(sc->request_bufflen);
+        hdr->cmdsn = cpu_to_be32(session->cmdsn);
+        session->cmdsn++;
+        hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
+        memcpy(hdr->cdb, sc->cmnd, sc->cmd_len);
+        memset(&hdr->cdb[sc->cmd_len], 0, MAX_COMMAND_SIZE - sc->cmd_len);
+
+	if (sc->sc_data_direction == DMA_TO_DEVICE) {
+		hdr->flags |= ISCSI_FLAG_CMD_WRITE;
+		/*
+		 * Write counters:
+		 *
+		 *	imm_count	bytes to be sent right after
+		 *			SCSI PDU Header
+		 *
+		 *	unsol_count	bytes(as Data-Out) to be sent
+		 *			without	R2T ack right after
+		 *			immediate data
+		 *
+		 *	r2t_data_count	bytes to be sent via R2T ack's
+		 *
+		 *      pad_count       bytes to be sent as zero-padding
+		 */
+		ctask->imm_count = 0;
+		ctask->unsol_count = 0;
+		ctask->unsol_datasn = 0;
+
+		if (session->imm_data_en) {
+			if (ctask->total_length >= session->first_burst)
+				ctask->imm_count = min(session->first_burst,
+							conn->max_xmit_dlength);
+			else
+				ctask->imm_count = min(ctask->total_length,
+							conn->max_xmit_dlength);
+			hton24(ctask->hdr->dlength, ctask->imm_count);
+		} else
+			zero_data(ctask->hdr->dlength);
+
+		if (!session->initial_r2t_en)
+			ctask->unsol_count = min(session->first_burst,
+				ctask->total_length) - ctask->imm_count;
+		if (!ctask->unsol_count)
+			/* No unsolicit Data-Out's */
+			ctask->hdr->flags |= ISCSI_FLAG_CMD_FINAL;
+	} else {
+		ctask->datasn = 0;
+		hdr->flags |= ISCSI_FLAG_CMD_FINAL;
+		zero_data(hdr->dlength);
+
+		if (sc->sc_data_direction == DMA_FROM_DEVICE)
+			hdr->flags |= ISCSI_FLAG_CMD_READ;
+	}
+
+	conn->scsicmd_pdus_cnt++;
+}
+EXPORT_SYMBOL_GPL(iscsi_prep_scsi_cmd_pdu);
+
+/**
+ * iscsi_complete_command - return command back to scsi-ml
+ * @session: iscsi session
+ * @ctask: iscsi cmd task
+ *
+ * Must be called with session lock.
+ * This function returns the scsi command to scsi-ml and returns
+ * the cmd task to the pool of available cmd tasks.
+ */
+static void iscsi_complete_command(struct iscsi_session *session,
+				   struct iscsi_cmd_task *ctask)
+{
+	struct scsi_cmnd *sc = ctask->sc;
+
+	ctask->sc = NULL;
+	list_del_init(&ctask->running);
+	__kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
+	sc->scsi_done(sc);
+}
+
+/**
+ * iscsi_cmd_rsp - SCSI Command Response processing
+ * @conn: iscsi connection
+ * @hdr: iscsi header
+ * @ctask: scsi command task
+ * @data: cmd data buffer
+ * @datalen: len of buffer
+ *
+ * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
+ * then completes the command and task.
+ **/
+static int iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
+			      struct iscsi_cmd_task *ctask, char *data,
+			      int datalen)
+{
+	int rc;
+	struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)hdr;
+	struct iscsi_session *session = conn->session;
+	struct scsi_cmnd *sc = ctask->sc;
+
+	rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)rhdr);
+	if (rc) {
+		sc->result = DID_ERROR << 16;
+		goto out;
+	}
+
+	conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
+
+	sc->result = (DID_OK << 16) | rhdr->cmd_status;
+
+	if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
+		sc->result = DID_ERROR << 16;
+		goto out;
+	}
+
+	if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
+		int senselen;
+
+		if (datalen < 2) {
+invalid_datalen:
+			printk(KERN_ERR "iscsi: Got CHECK_CONDITION but "
+			       "invalid data buffer size of %d\n", datalen);
+			sc->result = DID_BAD_TARGET << 16;
+			goto out;
+		}
+
+		senselen = (data[0] << 8) | data[1];
+		if (datalen < senselen)
+			goto invalid_datalen;
+
+		memcpy(sc->sense_buffer, data + 2,
+		       min(senselen, SCSI_SENSE_BUFFERSIZE));
+		debug_scsi("copied %d bytes of sense\n",
+			   min(senselen, SCSI_SENSE_BUFFERSIZE));
+	}
+
+	if (sc->sc_data_direction == DMA_TO_DEVICE)
+		goto out;
+
+	if (rhdr->flags & ISCSI_FLAG_CMD_UNDERFLOW) {
+		int res_count = be32_to_cpu(rhdr->residual_count);
+
+		if (res_count > 0 && res_count <= sc->request_bufflen)
+			sc->resid = res_count;
+		else
+			sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
+	} else if (rhdr->flags & ISCSI_FLAG_CMD_BIDI_UNDERFLOW)
+		sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
+	else if (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW)
+		sc->resid = be32_to_cpu(rhdr->residual_count);
+
+out:
+	debug_scsi("done [sc %lx res %d itt 0x%x]\n",
+		   (long)sc, sc->result, ctask->itt);
+	conn->scsirsp_pdus_cnt++;
+
+	iscsi_complete_command(conn->session, ctask);
+	return rc;
+}
+
+/**
+ * __iscsi_complete_pdu - complete pdu
+ * @conn: iscsi conn
+ * @hdr: iscsi header
+ * @data: data buffer
+ * @datalen: len of data buffer
+ *
+ * Completes pdu processing by freeing any resources allocated at
+ * queuecommand or send generic. session lock must be held and verify
+ * itt must have been called.
+ */
+int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
+			 char *data, int datalen)
+{
+	struct iscsi_session *session = conn->session;
+	int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
+	struct iscsi_cmd_task *ctask;
+	struct iscsi_mgmt_task *mtask;
+	uint32_t itt;
+
+	if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG))
+		itt = hdr->itt & ISCSI_ITT_MASK;
+	else
+		itt = hdr->itt;
+
+	if (itt < session->cmds_max) {
+		ctask = session->cmds[itt];
+
+		debug_scsi("cmdrsp [op 0x%x cid %d itt 0x%x len %d]\n",
+			   opcode, conn->id, ctask->itt, datalen);
+
+		switch(opcode) {
+		case ISCSI_OP_SCSI_CMD_RSP:
+			BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
+			rc = iscsi_scsi_cmd_rsp(conn, hdr, ctask, data,
+						datalen);
+			break;
+		case ISCSI_OP_SCSI_DATA_IN:
+			BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
+			if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
+				conn->scsirsp_pdus_cnt++;
+				iscsi_complete_command(session, ctask);
+			}
+			break;
+		case ISCSI_OP_R2T:
+			/* LLD handles this for now */
+			break;
+		default:
+			rc = ISCSI_ERR_BAD_OPCODE;
+			break;
+		}
+	} else if (itt >= ISCSI_MGMT_ITT_OFFSET &&
+		   itt < ISCSI_MGMT_ITT_OFFSET + session->mgmtpool_max) {
+		mtask = session->mgmt_cmds[itt - ISCSI_MGMT_ITT_OFFSET];
+
+		debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
+			   opcode, conn->id, mtask->itt, datalen);
+
+		rc = iscsi_check_assign_cmdsn(session,
+					      (struct iscsi_nopin*)hdr);
+		if (rc)
+			goto done;
+
+		switch(opcode) {
+		case ISCSI_OP_LOGOUT_RSP:
+			conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
+			/* fall through */
+		case ISCSI_OP_LOGIN_RSP:
+		case ISCSI_OP_TEXT_RSP:
+			/*
+			 * login related PDU's exp_statsn is handled in
+			 * userspace
+			 */
+			rc = iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen);
+			list_del(&mtask->running);
+			if (conn->login_mtask != mtask)
+				__kfifo_put(session->mgmtpool.queue,
+					    (void*)&mtask, sizeof(void*));
+			break;
+		case ISCSI_OP_SCSI_TMFUNC_RSP:
+			if (datalen) {
+				rc = ISCSI_ERR_PROTO;
+				break;
+			}
+
+			conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
+			conn->tmfrsp_pdus_cnt++;
+			if (conn->tmabort_state == TMABORT_INITIAL) {
+				conn->tmabort_state =
+					((struct iscsi_tm_rsp *)hdr)->
+					response == ISCSI_TMF_RSP_COMPLETE ?
+						TMABORT_SUCCESS:TMABORT_FAILED;
+				/* unblock eh_abort() */
+				wake_up(&conn->ehwait);
+			}
+			break;
+		case ISCSI_OP_NOOP_IN:
+			if (hdr->ttt != ISCSI_RESERVED_TAG) {
+				rc = ISCSI_ERR_PROTO;
+				break;
+			}
+			conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
+
+			rc = iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen);
+			list_del(&mtask->running);
+			if (conn->login_mtask != mtask)
+				__kfifo_put(session->mgmtpool.queue,
+					    (void*)&mtask, sizeof(void*));
+			break;
+		default:
+			rc = ISCSI_ERR_BAD_OPCODE;
+			break;
+		}
+	} else if (itt == ISCSI_RESERVED_TAG) {
+		switch(opcode) {
+		case ISCSI_OP_NOOP_IN:
+			if (!datalen) {
+				rc = iscsi_check_assign_cmdsn(session,
+						 (struct iscsi_nopin*)hdr);
+				if (!rc && hdr->ttt != ISCSI_RESERVED_TAG)
+					rc = iscsi_recv_pdu(conn->cls_conn,
+							    hdr, NULL, 0);
+			} else
+				rc = ISCSI_ERR_PROTO;
+			break;
+		case ISCSI_OP_REJECT:
+			/* we need sth like iscsi_reject_rsp()*/
+		case ISCSI_OP_ASYNC_EVENT:
+			conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
+			/* we need sth like iscsi_async_event_rsp() */
+			rc = ISCSI_ERR_BAD_OPCODE;
+			break;
+		default:
+			rc = ISCSI_ERR_BAD_OPCODE;
+			break;
+		}
+	} else
+		rc = ISCSI_ERR_BAD_ITT;
+
+done:
+	return rc;
+}
+EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);
+
+int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
+		       char *data, int datalen)
+{
+	int rc;
+
+	spin_lock(&conn->session->lock);
+	rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
+	spin_unlock(&conn->session->lock);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
+
+/* verify itt (itt encoding: age+cid+itt) */
+int iscsi_verify_itt(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
+		     uint32_t *ret_itt)
+{
+	struct iscsi_session *session = conn->session;
+	struct iscsi_cmd_task *ctask;
+	uint32_t itt;
+
+	if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
+		if ((hdr->itt & ISCSI_AGE_MASK) !=
+		    (session->age << ISCSI_AGE_SHIFT)) {
+			printk(KERN_ERR "iscsi: received itt %x expected "
+				"session age (%x)\n", hdr->itt,
+				session->age & ISCSI_AGE_MASK);
+			return ISCSI_ERR_BAD_ITT;
+		}
+
+		if ((hdr->itt & ISCSI_CID_MASK) !=
+		    (conn->id << ISCSI_CID_SHIFT)) {
+			printk(KERN_ERR "iscsi: received itt %x, expected "
+				"CID (%x)\n", hdr->itt, conn->id);
+			return ISCSI_ERR_BAD_ITT;
+		}
+		itt = hdr->itt & ISCSI_ITT_MASK;
+	} else
+		itt = hdr->itt;
+
+	if (itt < session->cmds_max) {
+		ctask = session->cmds[itt];
+
+		if (!ctask->sc) {
+			printk(KERN_INFO "iscsi: dropping ctask with "
+			       "itt 0x%x\n", ctask->itt);
+			/* force drop */
+			return ISCSI_ERR_NO_SCSI_CMD;
+		}
+
+		if (ctask->sc->SCp.phase != session->age) {
+			printk(KERN_ERR "iscsi: ctask's session age %d, "
+				"expected %d\n", ctask->sc->SCp.phase,
+				session->age);
+			return ISCSI_ERR_SESSION_FAILED;
+		}
+	}
+
+	*ret_itt = itt;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(iscsi_verify_itt);
+
+void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
+{
+	struct iscsi_session *session = conn->session;
+	unsigned long flags;
+
+	spin_lock_irqsave(&session->lock, flags);
+	if (session->state == ISCSI_STATE_FAILED) {
+		spin_unlock_irqrestore(&session->lock, flags);
+		return;
+	}
+
+	if (conn->stop_stage == 0)
+		session->state = ISCSI_STATE_FAILED;
+	spin_unlock_irqrestore(&session->lock, flags);
+	set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
+	set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
+	iscsi_conn_error(conn->cls_conn, err);
+}
+EXPORT_SYMBOL_GPL(iscsi_conn_failure);
+
+/**
+ * iscsi_data_xmit - xmit any command into the scheduled connection
+ * @conn: iscsi connection
+ *
+ * Notes:
+ *	The function can return -EAGAIN in which case the caller must
+ *	re-schedule it again later or recover. '0' return code means
+ *	successful xmit.
+ **/
+static int iscsi_data_xmit(struct iscsi_conn *conn)
+{
+	struct iscsi_transport *tt;
+	int rc = 0;
+
+	if (unlikely(conn->suspend_tx)) {
+		debug_scsi("conn %d Tx suspended!\n", conn->id);
+		return -ENODATA;
+	}
+	tt = conn->session->tt;
+
+	/*
+	 * Transmit in the following order:
+	 *
+	 * 1) un-finished xmit (ctask or mtask)
+	 * 2) immediate control PDUs
+	 * 3) write data
+	 * 4) SCSI commands
+	 * 5) non-immediate control PDUs
+	 *
+	 * No need to lock around __kfifo_get as long as
+	 * there's one producer and one consumer.
+	 */
+
+	BUG_ON(conn->ctask && conn->mtask);
+
+	if (conn->ctask) {
+		rc = tt->xmit_cmd_task(conn, conn->ctask);
+		if (rc)
+			goto again;
+		/* done with this in-progress ctask */
+		conn->ctask = NULL;
+	}
+	if (conn->mtask) {
+		rc = tt->xmit_mgmt_task(conn, conn->mtask);
+	        if (rc)
+		        goto again;
+		/* done with this in-progress mtask */
+		conn->mtask = NULL;
+	}
+
+	/* process immediate first */
+        if (unlikely(__kfifo_len(conn->immqueue))) {
+	        while (__kfifo_get(conn->immqueue, (void*)&conn->mtask,
+			           sizeof(void*))) {
+			spin_lock_bh(&conn->session->lock);
+			list_add_tail(&conn->mtask->running,
+				      &conn->mgmt_run_list);
+			spin_unlock_bh(&conn->session->lock);
+			rc = tt->xmit_mgmt_task(conn, conn->mtask);
+		        if (rc)
+			        goto again;
+	        }
+		/* done with this mtask */
+		conn->mtask = NULL;
+	}
+
+	/* process command queue */
+	while (__kfifo_get(conn->xmitqueue, (void*)&conn->ctask,
+			   sizeof(void*))) {
+		/*
+		 * iscsi tcp may readd the task to the xmitqueue to send
+		 * write data
+		 */
+		spin_lock_bh(&conn->session->lock);
+		if (list_empty(&conn->ctask->running))
+			list_add_tail(&conn->ctask->running, &conn->run_list);
+		spin_unlock_bh(&conn->session->lock);
+		rc = tt->xmit_cmd_task(conn, conn->ctask);
+		if (rc)
+			goto again;
+	}
+	/* done with this ctask */
+	conn->ctask = NULL;
+
+	/* process the rest control plane PDUs, if any */
+        if (unlikely(__kfifo_len(conn->mgmtqueue))) {
+	        while (__kfifo_get(conn->mgmtqueue, (void*)&conn->mtask,
+			           sizeof(void*))) {
+			spin_lock_bh(&conn->session->lock);
+			list_add_tail(&conn->mtask->running,
+				      &conn->mgmt_run_list);
+			spin_unlock_bh(&conn->session->lock);
+		        rc = tt->xmit_mgmt_task(conn, conn->mtask);
+			if (rc)
+			        goto again;
+	        }
+		/* done with this mtask */
+		conn->mtask = NULL;
+	}
+
+	return -ENODATA;
+
+again:
+	if (unlikely(conn->suspend_tx))
+		return -ENODATA;
+
+	return rc;
+}
+
+static void iscsi_xmitworker(void *data)
+{
+	struct iscsi_conn *conn = data;
+	int rc;
+	/*
+	 * serialize Xmit worker on a per-connection basis.
+	 */
+	mutex_lock(&conn->xmitmutex);
+	do {
+		rc = iscsi_data_xmit(conn);
+	} while (rc >= 0 || rc == -EAGAIN);
+	mutex_unlock(&conn->xmitmutex);
+}
+
+enum {
+	FAILURE_BAD_HOST = 1,
+	FAILURE_SESSION_FAILED,
+	FAILURE_SESSION_FREED,
+	FAILURE_WINDOW_CLOSED,
+	FAILURE_SESSION_TERMINATE,
+	FAILURE_SESSION_IN_RECOVERY,
+	FAILURE_SESSION_RECOVERY_TIMEOUT,
+};
+
+int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
+{
+	struct Scsi_Host *host;
+	int reason = 0;
+	struct iscsi_session *session;
+	struct iscsi_conn *conn;
+	struct iscsi_cmd_task *ctask = NULL;
+
+	sc->scsi_done = done;
+	sc->result = 0;
+
+	host = sc->device->host;
+	session = iscsi_hostdata(host->hostdata);
+
+	spin_lock(&session->lock);
+
+	/*
+	 * ISCSI_STATE_FAILED is a temp. state. The recovery
+	 * code will decide what is best to do with command queued
+	 * during this time
+	 */
+	if (session->state != ISCSI_STATE_LOGGED_IN &&
+	    session->state != ISCSI_STATE_FAILED) {
+		/*
+		 * to handle the race between when we set the recovery state
+		 * and block the session we requeue here (commands could
+		 * be entering our queuecommand while a block is starting
+		 * up because the block code is not locked)
+		 */
+		if (session->state == ISCSI_STATE_IN_RECOVERY) {
+			reason = FAILURE_SESSION_IN_RECOVERY;
+			goto reject;
+		}
+
+		if (session->state == ISCSI_STATE_RECOVERY_FAILED)
+			reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
+		else if (session->state == ISCSI_STATE_TERMINATE)
+			reason = FAILURE_SESSION_TERMINATE;
+		else
+			reason = FAILURE_SESSION_FREED;
+		goto fault;
+	}
+
+	/*
+	 * Check for iSCSI window and take care of CmdSN wrap-around
+	 */
+	if ((int)(session->max_cmdsn - session->cmdsn) < 0) {
+		reason = FAILURE_WINDOW_CLOSED;
+		goto reject;
+	}
+
+	conn = session->leadconn;
+
+	__kfifo_get(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
+	sc->SCp.phase = session->age;
+	sc->SCp.ptr = (char *)ctask;
+
+	ctask->mtask = NULL;
+	ctask->conn = conn;
+	ctask->sc = sc;
+	INIT_LIST_HEAD(&ctask->running);
+	ctask->total_length = sc->request_bufflen;
+	iscsi_prep_scsi_cmd_pdu(ctask);
+
+	session->tt->init_cmd_task(ctask);
+
+	__kfifo_put(conn->xmitqueue, (void*)&ctask, sizeof(void*));
+	debug_scsi(
+	       "ctask enq [%s cid %d sc %lx itt 0x%x len %d cmdsn %d win %d]\n",
+		sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
+		conn->id, (long)sc, ctask->itt, sc->request_bufflen,
+		session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
+	spin_unlock(&session->lock);
+
+	scsi_queue_work(host, &conn->xmitwork);
+	return 0;
+
+reject:
+	spin_unlock(&session->lock);
+	debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
+	return SCSI_MLQUEUE_HOST_BUSY;
+
+fault:
+	spin_unlock(&session->lock);
+	printk(KERN_ERR "iscsi: cmd 0x%x is not queued (%d)\n",
+	       sc->cmnd[0], reason);
+	sc->result = (DID_NO_CONNECT << 16);
+	sc->resid = sc->request_bufflen;
+	sc->scsi_done(sc);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(iscsi_queuecommand);
+
+int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
+{
+	if (depth > ISCSI_MAX_CMD_PER_LUN)
+		depth = ISCSI_MAX_CMD_PER_LUN;
+	scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
+	return sdev->queue_depth;
+}
+EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
+
+static int
+iscsi_conn_send_generic(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
+			char *data, uint32_t data_size)
+{
+	struct iscsi_session *session = conn->session;
+	struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
+	struct iscsi_mgmt_task *mtask;
+
+	spin_lock_bh(&session->lock);
+	if (session->state == ISCSI_STATE_TERMINATE) {
+		spin_unlock_bh(&session->lock);
+		return -EPERM;
+	}
+	if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
+	    hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
+		/*
+		 * Login and Text are sent serially, in
+		 * request-followed-by-response sequence.
+		 * Same mtask can be used. Same ITT must be used.
+		 * Note that login_mtask is preallocated at conn_create().
+		 */
+		mtask = conn->login_mtask;
+	else {
+		BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
+		BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
+
+		nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
+		if (!__kfifo_get(session->mgmtpool.queue,
+				 (void*)&mtask, sizeof(void*))) {
+			spin_unlock_bh(&session->lock);
+			return -ENOSPC;
+		}
+	}
+
+	/*
+	 * pre-format CmdSN for outgoing PDU.
+	 */
+	if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
+		hdr->itt = mtask->itt | (conn->id << ISCSI_CID_SHIFT) |
+			   (session->age << ISCSI_AGE_SHIFT);
+		nop->cmdsn = cpu_to_be32(session->cmdsn);
+		if (conn->c_stage == ISCSI_CONN_STARTED &&
+		    !(hdr->opcode & ISCSI_OP_IMMEDIATE))
+			session->cmdsn++;
+	} else
+		/* do not advance CmdSN */
+		nop->cmdsn = cpu_to_be32(session->cmdsn);
+
+	if (data_size) {
+		memcpy(mtask->data, data, data_size);
+		mtask->data_count = data_size;
+	} else
+		mtask->data_count = 0;
+
+	INIT_LIST_HEAD(&mtask->running);
+	memcpy(mtask->hdr, hdr, sizeof(struct iscsi_hdr));
+	if (session->tt->init_mgmt_task)
+		session->tt->init_mgmt_task(conn, mtask, data, data_size);
+	spin_unlock_bh(&session->lock);
+
+	debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
+		   hdr->opcode, hdr->itt, data_size);
+
+	/*
+	 * since send_pdu() could be called at least from two contexts,
+	 * we need to serialize __kfifo_put, so we don't have to take
+	 * additional lock on fast data-path
+	 */
+        if (hdr->opcode & ISCSI_OP_IMMEDIATE)
+	        __kfifo_put(conn->immqueue, (void*)&mtask, sizeof(void*));
+	else
+	        __kfifo_put(conn->mgmtqueue, (void*)&mtask, sizeof(void*));
+
+	scsi_queue_work(session->host, &conn->xmitwork);
+	return 0;
+}
+
+int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
+			char *data, uint32_t data_size)
+{
+	struct iscsi_conn *conn = cls_conn->dd_data;
+	int rc;
+
+	mutex_lock(&conn->xmitmutex);
+	rc = iscsi_conn_send_generic(conn, hdr, data, data_size);
+	mutex_unlock(&conn->xmitmutex);
+
+	return rc;
+}
+EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
+
+void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
+{
+	struct iscsi_session *session = class_to_transport_session(cls_session);
+	struct iscsi_conn *conn = session->leadconn;
+
+	spin_lock_bh(&session->lock);
+	if (session->state != ISCSI_STATE_LOGGED_IN) {
+		session->state = ISCSI_STATE_RECOVERY_FAILED;
+		if (conn)
+			wake_up(&conn->ehwait);
+	}
+	spin_unlock_bh(&session->lock);
+}
+EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
+
+int iscsi_eh_host_reset(struct scsi_cmnd *sc)
+{
+	struct Scsi_Host *host = sc->device->host;
+	struct iscsi_session *session = iscsi_hostdata(host->hostdata);
+	struct iscsi_conn *conn = session->leadconn;
+	int fail_session = 0;
+
+	spin_lock_bh(&session->lock);
+	if (session->state == ISCSI_STATE_TERMINATE) {
+failed:
+		debug_scsi("failing host reset: session terminated "
+			   "[CID %d age %d]", conn->id, session->age);
+		spin_unlock_bh(&session->lock);
+		return FAILED;
+	}
+
+	if (sc->SCp.phase == session->age) {
+		debug_scsi("failing connection CID %d due to SCSI host reset",
+			   conn->id);
+		fail_session = 1;
+	}
+	spin_unlock_bh(&session->lock);
+
+	/*
+	 * we drop the lock here but the leadconn cannot be destoyed while
+	 * we are in the scsi eh
+	 */
+	if (fail_session)
+		iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
+
+	debug_scsi("iscsi_eh_host_reset wait for relogin\n");
+	wait_event_interruptible(conn->ehwait,
+				 session->state == ISCSI_STATE_TERMINATE ||
+				 session->state == ISCSI_STATE_LOGGED_IN ||
+				 session->state == ISCSI_STATE_RECOVERY_FAILED);
+	if (signal_pending(current))
+		flush_signals(current);
+
+	spin_lock_bh(&session->lock);
+	if (session->state == ISCSI_STATE_LOGGED_IN)
+		printk(KERN_INFO "iscsi: host reset succeeded\n");
+	else
+		goto failed;
+	spin_unlock_bh(&session->lock);
+
+	return SUCCESS;
+}
+EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
+
+static void iscsi_tmabort_timedout(unsigned long data)
+{
+	struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)data;
+	struct iscsi_conn *conn = ctask->conn;
+	struct iscsi_session *session = conn->session;
+
+	spin_lock(&session->lock);
+	if (conn->tmabort_state == TMABORT_INITIAL) {
+		conn->tmabort_state = TMABORT_TIMEDOUT;
+		debug_scsi("tmabort timedout [sc %p itt 0x%x]\n",
+			ctask->sc, ctask->itt);
+		/* unblock eh_abort() */
+		wake_up(&conn->ehwait);
+	}
+	spin_unlock(&session->lock);
+}
+
+/* must be called with the mutex lock */
+static int iscsi_exec_abort_task(struct scsi_cmnd *sc,
+				 struct iscsi_cmd_task *ctask)
+{
+	struct iscsi_conn *conn = ctask->conn;
+	struct iscsi_session *session = conn->session;
+	struct iscsi_tm *hdr = &conn->tmhdr;
+	int rc;
+
+	/*
+	 * ctask timed out but session is OK requests must be serialized.
+	 */
+	memset(hdr, 0, sizeof(struct iscsi_tm));
+	hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
+	hdr->flags = ISCSI_TM_FUNC_ABORT_TASK;
+	hdr->flags |= ISCSI_FLAG_CMD_FINAL;
+	memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
+	hdr->rtt = ctask->hdr->itt;
+	hdr->refcmdsn = ctask->hdr->cmdsn;
+
+	rc = iscsi_conn_send_generic(conn, (struct iscsi_hdr *)hdr,
+				     NULL, 0);
+	if (rc) {
+		iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
+		debug_scsi("abort sent failure [itt 0x%x] %d", ctask->itt, rc);
+		return rc;
+	}
+
+	debug_scsi("abort sent [itt 0x%x]\n", ctask->itt);
+
+	spin_lock_bh(&session->lock);
+	ctask->mtask = (struct iscsi_mgmt_task *)
+			session->mgmt_cmds[(hdr->itt & ISCSI_ITT_MASK) -
+					ISCSI_MGMT_ITT_OFFSET];
+
+	if (conn->tmabort_state == TMABORT_INITIAL) {
+		conn->tmfcmd_pdus_cnt++;
+		conn->tmabort_timer.expires = 10*HZ + jiffies;
+		conn->tmabort_timer.function = iscsi_tmabort_timedout;
+		conn->tmabort_timer.data = (unsigned long)ctask;
+		add_timer(&conn->tmabort_timer);
+		debug_scsi("abort set timeout [itt 0x%x]", ctask->itt);
+	}
+	spin_unlock_bh(&session->lock);
+	mutex_unlock(&conn->xmitmutex);
+
+	/*
+	 * block eh thread until:
+	 *
+	 * 1) abort response
+	 * 2) abort timeout
+	 * 3) session is terminated or restarted or userspace has
+	 * given up on recovery
+	 */
+	wait_event_interruptible(conn->ehwait,
+				 sc->SCp.phase != session->age ||
+				 session->state != ISCSI_STATE_LOGGED_IN ||
+				 conn->tmabort_state != TMABORT_INITIAL);
+	if (signal_pending(current))
+		flush_signals(current);
+	del_timer_sync(&conn->tmabort_timer);
+
+	mutex_lock(&conn->xmitmutex);
+	return 0;
+}
+
+/*
+ * xmit mutex and session lock must be held
+ */
+#define iscsi_remove_task(tasktype)					\
+static struct iscsi_##tasktype *					\
+iscsi_remove_##tasktype(struct kfifo *fifo, uint32_t itt)		\
+{									\
+	int i, nr_tasks = __kfifo_len(fifo) / sizeof(void*);		\
+	struct iscsi_##tasktype *task;					\
+									\
+	debug_scsi("searching %d tasks\n", nr_tasks);			\
+									\
+	for (i = 0; i < nr_tasks; i++) {				\
+		__kfifo_get(fifo, (void*)&task, sizeof(void*));		\
+		debug_scsi("check task %u\n", task->itt);		\
+									\
+		if (task->itt == itt) {					\
+			debug_scsi("matched task\n");			\
+			return task;					\
+		}							\
+									\
+		__kfifo_put(fifo, (void*)&task, sizeof(void*));		\
+	}								\
+	return NULL;							\
+}
+
+iscsi_remove_task(mgmt_task);
+iscsi_remove_task(cmd_task);
+
+static int iscsi_ctask_mtask_cleanup(struct iscsi_cmd_task *ctask)
+{
+	struct iscsi_conn *conn = ctask->conn;
+	struct iscsi_session *session = conn->session;
+
+	if (!ctask->mtask)
+		return -EINVAL;
+
+	if (!iscsi_remove_mgmt_task(conn->immqueue, ctask->mtask->itt))
+		list_del(&ctask->mtask->running);
+	__kfifo_put(session->mgmtpool.queue, (void*)&ctask->mtask,
+		    sizeof(void*));
+	ctask->mtask = NULL;
+	return 0;
+}
+
+/*
+ * session lock and xmitmutex must be held
+ */
+static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
+			 int err)
+{
+	struct scsi_cmnd *sc;
+
+	conn->session->tt->cleanup_cmd_task(conn, ctask);
+	iscsi_ctask_mtask_cleanup(ctask);
+
+	sc = ctask->sc;
+	if (!sc)
+		return;
+	sc->result = err;
+	sc->resid = sc->request_bufflen;
+	iscsi_complete_command(conn->session, ctask);
+}
+
+int iscsi_eh_abort(struct scsi_cmnd *sc)
+{
+	struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
+	struct iscsi_conn *conn = ctask->conn;
+	struct iscsi_session *session = conn->session;
+	struct iscsi_cmd_task *pending_ctask;
+	int rc;
+
+	conn->eh_abort_cnt++;
+	debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
+
+	mutex_lock(&conn->xmitmutex);
+	spin_lock_bh(&session->lock);
+
+	/*
+	 * If we are not logged in or we have started a new session
+	 * then let the host reset code handle this
+	 */
+	if (session->state != ISCSI_STATE_LOGGED_IN ||
+	    sc->SCp.phase != session->age)
+		goto failed;
+
+	/* ctask completed before time out */
+	if (!ctask->sc)
+		goto success;
+
+	/* what should we do here ? */
+	if (conn->ctask == ctask) {
+		printk(KERN_INFO "iscsi: sc %p itt 0x%x partially sent. "
+		       "Failing abort\n", sc, ctask->itt);
+		goto failed;
+	}
+
+	/* check for the easy pending cmd abort */
+	pending_ctask = iscsi_remove_cmd_task(conn->xmitqueue, ctask->itt);
+	if (pending_ctask) {
+		/* iscsi_tcp queues write transfers on the xmitqueue */
+		if (list_empty(&pending_ctask->running)) {
+			debug_scsi("found pending task\n");
+			goto success;
+		} else
+			__kfifo_put(conn->xmitqueue, (void*)&pending_ctask,
+				    sizeof(void*));
+	}
+
+	conn->tmabort_state = TMABORT_INITIAL;
+
+	spin_unlock_bh(&session->lock);
+	rc = iscsi_exec_abort_task(sc, ctask);
+	spin_lock_bh(&session->lock);
+
+	iscsi_ctask_mtask_cleanup(ctask);
+	if (rc || sc->SCp.phase != session->age ||
+	    session->state != ISCSI_STATE_LOGGED_IN)
+		goto failed;
+
+	/* ctask completed before tmf abort response */
+	if (!ctask->sc) {
+		debug_scsi("sc completed while abort in progress\n");
+		goto success;
+	}
+
+	if (conn->tmabort_state != TMABORT_SUCCESS) {
+		spin_unlock_bh(&session->lock);
+		iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
+		spin_lock_bh(&session->lock);
+		goto failed;
+	}
+
+success:
+	debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
+	spin_unlock_bh(&session->lock);
+
+	/*
+	 * clean up task if aborted. we have the xmitmutex so grab
+	 * the recv lock as a writer
+	 */
+	write_lock_bh(conn->recv_lock);
+	spin_lock(&session->lock);
+	fail_command(conn, ctask, DID_ABORT << 16);
+	spin_unlock(&session->lock);
+	write_unlock_bh(conn->recv_lock);
+
+	mutex_unlock(&conn->xmitmutex);
+	return SUCCESS;
+
+failed:
+	spin_unlock_bh(&session->lock);
+	mutex_unlock(&conn->xmitmutex);
+
+	debug_scsi("abort failed [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
+	return FAILED;
+}
+EXPORT_SYMBOL_GPL(iscsi_eh_abort);
+
+int
+iscsi_pool_init(struct iscsi_queue *q, int max, void ***items, int item_size)
+{
+	int i;
+
+	*items = kmalloc(max * sizeof(void*), GFP_KERNEL);
+	if (*items == NULL)
+		return -ENOMEM;
+
+	q->max = max;
+	q->pool = kmalloc(max * sizeof(void*), GFP_KERNEL);
+	if (q->pool == NULL) {
+		kfree(*items);
+		return -ENOMEM;
+	}
+
+	q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
+			      GFP_KERNEL, NULL);
+	if (q->queue == ERR_PTR(-ENOMEM)) {
+		kfree(q->pool);
+		kfree(*items);
+		return -ENOMEM;
+	}
+
+	for (i = 0; i < max; i++) {
+		q->pool[i] = kmalloc(item_size, GFP_KERNEL);
+		if (q->pool[i] == NULL) {
+			int j;
+
+			for (j = 0; j < i; j++)
+				kfree(q->pool[j]);
+
+			kfifo_free(q->queue);
+			kfree(q->pool);
+			kfree(*items);
+			return -ENOMEM;
+		}
+		memset(q->pool[i], 0, item_size);
+		(*items)[i] = q->pool[i];
+		__kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(iscsi_pool_init);
+
+void iscsi_pool_free(struct iscsi_queue *q, void **items)
+{
+	int i;
+
+	for (i = 0; i < q->max; i++)
+		kfree(items[i]);
+	kfree(q->pool);
+	kfree(items);
+}
+EXPORT_SYMBOL_GPL(iscsi_pool_free);
+
+/*
+ * iSCSI Session's hostdata organization:
+ *
+ *    *------------------* <== hostdata_session(host->hostdata)
+ *    | ptr to class sess|
+ *    |------------------| <== iscsi_hostdata(host->hostdata)
+ *    | iscsi_session    |
+ *    *------------------*
+ */
+
+#define hostdata_privsize(_sz)	(sizeof(unsigned long) + _sz + \
+				 _sz % sizeof(unsigned long))
+
+#define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
+
+/**
+ * iscsi_session_setup - create iscsi cls session and host and session
+ * @scsit: scsi transport template
+ * @iscsit: iscsi transport template
+ * @initial_cmdsn: initial CmdSN
+ * @hostno: host no allocated
+ *
+ * This can be used by software iscsi_transports that allocate
+ * a session per scsi host.
+ **/
+struct iscsi_cls_session *
+iscsi_session_setup(struct iscsi_transport *iscsit,
+		    struct scsi_transport_template *scsit,
+		    int cmd_task_size, int mgmt_task_size,
+		    uint32_t initial_cmdsn, uint32_t *hostno)
+{
+	struct Scsi_Host *shost;
+	struct iscsi_session *session;
+	struct iscsi_cls_session *cls_session;
+	int cmd_i;
+
+	shost = scsi_host_alloc(iscsit->host_template,
+				hostdata_privsize(sizeof(*session)));
+	if (!shost)
+		return NULL;
+
+	shost->max_id = 1;
+	shost->max_channel = 0;
+	shost->max_lun = iscsit->max_lun;
+	shost->max_cmd_len = iscsit->max_cmd_len;
+	shost->transportt = scsit;
+	shost->transportt->create_work_queue = 1;
+	*hostno = shost->host_no;
+
+	session = iscsi_hostdata(shost->hostdata);
+	memset(session, 0, sizeof(struct iscsi_session));
+	session->host = shost;
+	session->state = ISCSI_STATE_FREE;
+	session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
+	session->cmds_max = ISCSI_XMIT_CMDS_MAX;
+	session->cmdsn = initial_cmdsn;
+	session->exp_cmdsn = initial_cmdsn + 1;
+	session->max_cmdsn = initial_cmdsn + 1;
+	session->max_r2t = 1;
+	session->tt = iscsit;
+
+	/* initialize SCSI PDU commands pool */
+	if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
+			    (void***)&session->cmds,
+			    cmd_task_size + sizeof(struct iscsi_cmd_task)))
+		goto cmdpool_alloc_fail;
+
+	/* pre-format cmds pool with ITT */
+	for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
+		struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
+
+		if (cmd_task_size)
+			ctask->dd_data = &ctask[1];
+		ctask->itt = cmd_i;
+	}
+
+	spin_lock_init(&session->lock);
+	INIT_LIST_HEAD(&session->connections);
+
+	/* initialize immediate command pool */
+	if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
+			   (void***)&session->mgmt_cmds,
+			   mgmt_task_size + sizeof(struct iscsi_mgmt_task)))
+		goto mgmtpool_alloc_fail;
+
+
+	/* pre-format immediate cmds pool with ITT */
+	for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
+		struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
+
+		if (mgmt_task_size)
+			mtask->dd_data = &mtask[1];
+		mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
+	}
+
+	if (scsi_add_host(shost, NULL))
+		goto add_host_fail;
+
+	cls_session = iscsi_create_session(shost, iscsit, 0);
+	if (!cls_session)
+		goto cls_session_fail;
+	*(unsigned long*)shost->hostdata = (unsigned long)cls_session;
+
+	return cls_session;
+
+cls_session_fail:
+	scsi_remove_host(shost);
+add_host_fail:
+	iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
+mgmtpool_alloc_fail:
+	iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
+cmdpool_alloc_fail:
+	scsi_host_put(shost);
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(iscsi_session_setup);
+
+/**
+ * iscsi_session_teardown - destroy session, host, and cls_session
+ * shost: scsi host
+ *
+ * This can be used by software iscsi_transports that allocate
+ * a session per scsi host.
+ **/
+void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
+{
+	struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
+	struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
+
+	scsi_remove_host(shost);
+
+	iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
+	iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
+
+	iscsi_destroy_session(cls_session);
+	scsi_host_put(shost);
+}
+EXPORT_SYMBOL_GPL(iscsi_session_teardown);
+
+/**
+ * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
+ * @cls_session: iscsi_cls_session
+ * @conn_idx: cid
+ **/
+struct iscsi_cls_conn *
+iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
+{
+	struct iscsi_session *session = class_to_transport_session(cls_session);
+	struct iscsi_conn *conn;
+	struct iscsi_cls_conn *cls_conn;
+	char *data;
+
+	cls_conn = iscsi_create_conn(cls_session, conn_idx);
+	if (!cls_conn)
+		return NULL;
+	conn = cls_conn->dd_data;
+	memset(conn, 0, sizeof(*conn));
+
+	conn->session = session;
+	conn->cls_conn = cls_conn;
+	conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
+	conn->id = conn_idx;
+	conn->exp_statsn = 0;
+	conn->tmabort_state = TMABORT_INITIAL;
+	INIT_LIST_HEAD(&conn->run_list);
+	INIT_LIST_HEAD(&conn->mgmt_run_list);
+
+	/* initialize general xmit PDU commands queue */
+	conn->xmitqueue = kfifo_alloc(session->cmds_max * sizeof(void*),
+					GFP_KERNEL, NULL);
+	if (conn->xmitqueue == ERR_PTR(-ENOMEM))
+		goto xmitqueue_alloc_fail;
+
+	/* initialize general immediate & non-immediate PDU commands queue */
+	conn->immqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
+			                GFP_KERNEL, NULL);
+	if (conn->immqueue == ERR_PTR(-ENOMEM))
+		goto immqueue_alloc_fail;
+
+	conn->mgmtqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
+			                GFP_KERNEL, NULL);
+	if (conn->mgmtqueue == ERR_PTR(-ENOMEM))
+		goto mgmtqueue_alloc_fail;
+
+	INIT_WORK(&conn->xmitwork, iscsi_xmitworker, conn);
+
+	/* allocate login_mtask used for the login/text sequences */
+	spin_lock_bh(&session->lock);
+	if (!__kfifo_get(session->mgmtpool.queue,
+                         (void*)&conn->login_mtask,
+			 sizeof(void*))) {
+		spin_unlock_bh(&session->lock);
+		goto login_mtask_alloc_fail;
+	}
+	spin_unlock_bh(&session->lock);
+
+	data = kmalloc(DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH, GFP_KERNEL);
+	if (!data)
+		goto login_mtask_data_alloc_fail;
+	conn->login_mtask->data = data;
+
+	init_timer(&conn->tmabort_timer);
+	mutex_init(&conn->xmitmutex);
+	init_waitqueue_head(&conn->ehwait);
+
+	return cls_conn;
+
+login_mtask_data_alloc_fail:
+	__kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
+		    sizeof(void*));
+login_mtask_alloc_fail:
+	kfifo_free(conn->mgmtqueue);
+mgmtqueue_alloc_fail:
+	kfifo_free(conn->immqueue);
+immqueue_alloc_fail:
+	kfifo_free(conn->xmitqueue);
+xmitqueue_alloc_fail:
+	iscsi_destroy_conn(cls_conn);
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(iscsi_conn_setup);
+
+/**
+ * iscsi_conn_teardown - teardown iscsi connection
+ * cls_conn: iscsi class connection
+ *
+ * TODO: we may need to make this into a two step process
+ * like scsi-mls remove + put host
+ */
+void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
+{
+	struct iscsi_conn *conn = cls_conn->dd_data;
+	struct iscsi_session *session = conn->session;
+	unsigned long flags;
+
+	set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
+	mutex_lock(&conn->xmitmutex);
+	if (conn->c_stage == ISCSI_CONN_INITIAL_STAGE) {
+		if (session->tt->suspend_conn_recv)
+			session->tt->suspend_conn_recv(conn);
+
+		session->tt->terminate_conn(conn);
+	}
+
+	spin_lock_bh(&session->lock);
+	conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
+	if (session->leadconn == conn) {
+		/*
+		 * leading connection? then give up on recovery.
+		 */
+		session->state = ISCSI_STATE_TERMINATE;
+		wake_up(&conn->ehwait);
+	}
+	spin_unlock_bh(&session->lock);
+
+	mutex_unlock(&conn->xmitmutex);
+
+	/*
+	 * Block until all in-progress commands for this connection
+	 * time out or fail.
+	 */
+	for (;;) {
+		spin_lock_irqsave(session->host->host_lock, flags);
+		if (!session->host->host_busy) { /* OK for ERL == 0 */
+			spin_unlock_irqrestore(session->host->host_lock, flags);
+			break;
+		}
+		spin_unlock_irqrestore(session->host->host_lock, flags);
+		msleep_interruptible(500);
+		printk(KERN_INFO "iscsi: scsi conn_destroy(): host_busy %d "
+		       "host_failed %d\n", session->host->host_busy,
+		       session->host->host_failed);
+		/*
+		 * force eh_abort() to unblock
+		 */
+		wake_up(&conn->ehwait);
+	}
+
+	spin_lock_bh(&session->lock);
+	kfree(conn->login_mtask->data);
+	__kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
+		    sizeof(void*));
+	list_del(&conn->item);
+	if (list_empty(&session->connections))
+		session->leadconn = NULL;
+	if (session->leadconn && session->leadconn == conn)
+		session->leadconn = container_of(session->connections.next,
+			struct iscsi_conn, item);
+
+	if (session->leadconn == NULL)
+		/* no connections exits.. reset sequencing */
+		session->cmdsn = session->max_cmdsn = session->exp_cmdsn = 1;
+	spin_unlock_bh(&session->lock);
+
+	kfifo_free(conn->xmitqueue);
+	kfifo_free(conn->immqueue);
+	kfifo_free(conn->mgmtqueue);
+
+	iscsi_destroy_conn(cls_conn);
+}
+EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
+
+int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
+{
+	struct iscsi_conn *conn = cls_conn->dd_data;
+	struct iscsi_session *session = conn->session;
+
+	if (session == NULL) {
+		printk(KERN_ERR "iscsi: can't start unbound connection\n");
+		return -EPERM;
+	}
+
+	spin_lock_bh(&session->lock);
+	conn->c_stage = ISCSI_CONN_STARTED;
+	session->state = ISCSI_STATE_LOGGED_IN;
+
+	switch(conn->stop_stage) {
+	case STOP_CONN_RECOVER:
+		/*
+		 * unblock eh_abort() if it is blocked. re-try all
+		 * commands after successful recovery
+		 */
+		conn->stop_stage = 0;
+		conn->tmabort_state = TMABORT_INITIAL;
+		session->age++;
+		spin_unlock_bh(&session->lock);
+
+		iscsi_unblock_session(session_to_cls(session));
+		wake_up(&conn->ehwait);
+		return 0;
+	case STOP_CONN_TERM:
+		conn->stop_stage = 0;
+		break;
+	default:
+		break;
+	}
+	spin_unlock_bh(&session->lock);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(iscsi_conn_start);
+
+static void
+flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
+{
+	struct iscsi_mgmt_task *mtask, *tmp;
+
+	/* handle pending */
+	while (__kfifo_get(conn->immqueue, (void*)&mtask, sizeof(void*)) ||
+	       __kfifo_get(conn->mgmtqueue, (void*)&mtask, sizeof(void*))) {
+		if (mtask == conn->login_mtask)
+			continue;
+		debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
+		__kfifo_put(session->mgmtpool.queue, (void*)&mtask,
+			    sizeof(void*));
+	}
+
+	/* handle running */
+	list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
+		debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
+		list_del(&mtask->running);
+
+		if (mtask == conn->login_mtask)
+			continue;
+		__kfifo_put(session->mgmtpool.queue, (void*)&mtask,
+			   sizeof(void*));
+	}
+
+	conn->mtask = NULL;
+}
+
+/* Fail commands. Mutex and session lock held and recv side suspended */
+static void fail_all_commands(struct iscsi_conn *conn)
+{
+	struct iscsi_cmd_task *ctask, *tmp;
+
+	/* flush pending */
+	while (__kfifo_get(conn->xmitqueue, (void*)&ctask, sizeof(void*))) {
+		debug_scsi("failing pending sc %p itt 0x%x\n", ctask->sc,
+			   ctask->itt);
+		fail_command(conn, ctask, DID_BUS_BUSY << 16);
+	}
+
+	/* fail all other running */
+	list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) {
+		debug_scsi("failing in progress sc %p itt 0x%x\n",
+			   ctask->sc, ctask->itt);
+		fail_command(conn, ctask, DID_BUS_BUSY << 16);
+	}
+
+	conn->ctask = NULL;
+}
+
+static void iscsi_start_session_recovery(struct iscsi_session *session,
+					 struct iscsi_conn *conn, int flag)
+{
+	int old_stop_stage;
+
+	spin_lock_bh(&session->lock);
+	if (conn->stop_stage == STOP_CONN_TERM) {
+		spin_unlock_bh(&session->lock);
+		return;
+	}
+
+	/*
+	 * When this is called for the in_login state, we only want to clean
+	 * up the login task and connection. We do not need to block and set
+	 * the recovery state again
+	 */
+	if (flag == STOP_CONN_TERM)
+		session->state = ISCSI_STATE_TERMINATE;
+	else if (conn->stop_stage != STOP_CONN_RECOVER)
+		session->state = ISCSI_STATE_IN_RECOVERY;
+
+	old_stop_stage = conn->stop_stage;
+	conn->stop_stage = flag;
+	conn->c_stage = ISCSI_CONN_STOPPED;
+	set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
+	spin_unlock_bh(&session->lock);
+
+	if (session->tt->suspend_conn_recv)
+		session->tt->suspend_conn_recv(conn);
+
+	mutex_lock(&conn->xmitmutex);
+	/*
+	 * for connection level recovery we should not calculate
+	 * header digest. conn->hdr_size used for optimization
+	 * in hdr_extract() and will be re-negotiated at
+	 * set_param() time.
+	 */
+	if (flag == STOP_CONN_RECOVER) {
+		conn->hdrdgst_en = 0;
+		conn->datadgst_en = 0;
+		if (session->state == ISCSI_STATE_IN_RECOVERY &&
+		    old_stop_stage != STOP_CONN_RECOVER) {
+			debug_scsi("blocking session\n");
+			iscsi_block_session(session_to_cls(session));
+		}
+	}
+
+	session->tt->terminate_conn(conn);
+	/*
+	 * flush queues.
+	 */
+	spin_lock_bh(&session->lock);
+	fail_all_commands(conn);
+	flush_control_queues(session, conn);
+	spin_unlock_bh(&session->lock);
+
+	mutex_unlock(&conn->xmitmutex);
+}
+
+void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
+{
+	struct iscsi_conn *conn = cls_conn->dd_data;
+	struct iscsi_session *session = conn->session;
+
+	switch (flag) {
+	case STOP_CONN_RECOVER:
+	case STOP_CONN_TERM:
+		iscsi_start_session_recovery(session, conn, flag);
+		break;
+	default:
+		printk(KERN_ERR "iscsi: invalid stop flag %d\n", flag);
+	}
+}
+EXPORT_SYMBOL_GPL(iscsi_conn_stop);
+
+int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
+		    struct iscsi_cls_conn *cls_conn, int is_leading)
+{
+	struct iscsi_session *session = class_to_transport_session(cls_session);
+	struct iscsi_conn *tmp = ERR_PTR(-EEXIST), *conn = cls_conn->dd_data;
+
+	/* lookup for existing connection */
+	spin_lock_bh(&session->lock);
+	list_for_each_entry(tmp, &session->connections, item) {
+		if (tmp == conn) {
+			if (conn->c_stage != ISCSI_CONN_STOPPED ||
+			    conn->stop_stage == STOP_CONN_TERM) {
+				printk(KERN_ERR "iscsi: can't bind "
+				       "non-stopped connection (%d:%d)\n",
+				       conn->c_stage, conn->stop_stage);
+				spin_unlock_bh(&session->lock);
+				return -EIO;
+			}
+			break;
+		}
+	}
+	if (tmp != conn) {
+		/* bind new iSCSI connection to session */
+		conn->session = session;
+		list_add(&conn->item, &session->connections);
+	}
+	spin_unlock_bh(&session->lock);
+
+	if (is_leading)
+		session->leadconn = conn;
+
+	/*
+	 * Unblock xmitworker(), Login Phase will pass through.
+	 */
+	clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
+	clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(iscsi_conn_bind);
+
+MODULE_AUTHOR("Mike Christie");
+MODULE_DESCRIPTION("iSCSI library functions");
+MODULE_LICENSE("GPL");