[SCSI] libfc: A modular Fibre Channel library

libFC is composed of 4 blocks supported by an exchange manager
and a framing library. The upper 4 layers are fc_lport, fc_disc,
fc_rport and fc_fcp. A LLD that uses libfc could choose to
either use libfc's block, or using the transport template
defined in libfc.h, override one or more blocks with its own
implementation.

The EM (Exchange Manager) manages exhcanges/sequences for all
commands- ELS, CT and FCP.

The framing library frames ELS and CT commands.

The fc_lport block manages the library's representation of the
host's FC enabled ports.

The fc_disc block manages discovery of targets as well as
handling changes that occur in the FC fabric (via. RSCN events).

The fc_rport block manages the library's representation of other
entities in the FC fabric. Currently the library uses this block
for targets, its peer when in point-to-point mode and the
directory server, but can be extended for other entities if
needed.

The fc_fcp block interacts with the scsi-ml and handles all
I/O.

Signed-off-by: Robert Love <[e-mail]>
[jejb: added include of delay.h to fix ppc64 compile prob spotted by sfr]
Signed-off-by: James Bottomley <[e-mail]>

drivers/scsi/Kconfig

···
 	  substantial, so users of MultiMaster Host Adapters may not
 	  wish to include it.
 
+config LIBFC
+	tristate "LibFC module"
+	depends on SCSI && SCSI_FC_ATTRS
+	---help---
+	  Fibre Channel library module
+
 config SCSI_DMX3191D
 	tristate "DMX3191D SCSI support"
 	depends on PCI && SCSI

drivers/scsi/Makefile

···
 obj-$(CONFIG_SCSI_SRP_ATTRS)	+= scsi_transport_srp.o
 obj-$(CONFIG_SCSI_DH)		+= device_handler/
 
+obj-$(CONFIG_LIBFC)		+= libfc/
 obj-$(CONFIG_ISCSI_TCP) 	+= libiscsi.o	libiscsi_tcp.o iscsi_tcp.o
 obj-$(CONFIG_INFINIBAND_ISER) 	+= libiscsi.o
 obj-$(CONFIG_SCSI_A4000T)	+= 53c700.o	a4000t.o

drivers/scsi/libfc/Makefile

···
+# $Id: Makefile
+
+obj-$(CONFIG_LIBFC) += libfc.o
+
+libfc-objs := \
+	fc_disc.o \
+	fc_exch.o \
+	fc_elsct.o \
+	fc_frame.o \
+	fc_lport.o \
+	fc_rport.o \
+	fc_fcp.o

drivers/scsi/libfc/fc_disc.c

···
+/*
+ * Copyright(c) 2007 - 2008 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Maintained at www.Open-FCoE.org
+ */
+
+/*
+ * Target Discovery
+ *
+ * This block discovers all FC-4 remote ports, including FCP initiators. It
+ * also handles RSCN events and re-discovery if necessary.
+ */
+
+/*
+ * DISC LOCKING
+ *
+ * The disc mutex is can be locked when acquiring rport locks, but may not
+ * be held when acquiring the lport lock. Refer to fc_lport.c for more
+ * details.
+ */
+
+#include <linux/timer.h>
+#include <linux/err.h>
+#include <asm/unaligned.h>
+
+#include <scsi/fc/fc_gs.h>
+
+#include <scsi/libfc.h>
+
+#define FC_DISC_RETRY_LIMIT	3	/* max retries */
+#define FC_DISC_RETRY_DELAY	500UL	/* (msecs) delay */
+
+#define	FC_DISC_DELAY		3
+
+static int fc_disc_debug;
+
+#define FC_DEBUG_DISC(fmt...)			\
+	do {					\
+		if (fc_disc_debug)		\
+			FC_DBG(fmt);		\
+	} while (0)
+
+static void fc_disc_gpn_ft_req(struct fc_disc *);
+static void fc_disc_gpn_ft_resp(struct fc_seq *, struct fc_frame *, void *);
+static int fc_disc_new_target(struct fc_disc *, struct fc_rport *,
+			      struct fc_rport_identifiers *);
+static void fc_disc_del_target(struct fc_disc *, struct fc_rport *);
+static void fc_disc_done(struct fc_disc *);
+static void fc_disc_timeout(struct work_struct *);
+static void fc_disc_single(struct fc_disc *, struct fc_disc_port *);
+static void fc_disc_restart(struct fc_disc *);
+
+/**
+ * fc_disc_lookup_rport - lookup a remote port by port_id
+ * @lport: Fibre Channel host port instance
+ * @port_id: remote port port_id to match
+ */
+struct fc_rport *fc_disc_lookup_rport(const struct fc_lport *lport,
+				      u32 port_id)
+{
+	const struct fc_disc *disc = &lport->disc;
+	struct fc_rport *rport, *found = NULL;
+	struct fc_rport_libfc_priv *rdata;
+	int disc_found = 0;
+
+	list_for_each_entry(rdata, &disc->rports, peers) {
+		rport = PRIV_TO_RPORT(rdata);
+		if (rport->port_id == port_id) {
+			disc_found = 1;
+			found = rport;
+			break;
+		}
+	}
+
+	if (!disc_found)
+		found = NULL;
+
+	return found;
+}
+
+/**
+ * fc_disc_stop_rports - delete all the remote ports associated with the lport
+ * @disc: The discovery job to stop rports on
+ *
+ * Locking Note: This function expects that the lport mutex is locked before
+ * calling it.
+ */
+void fc_disc_stop_rports(struct fc_disc *disc)
+{
+	struct fc_lport *lport;
+	struct fc_rport *rport;
+	struct fc_rport_libfc_priv *rdata, *next;
+
+	lport = disc->lport;
+
+	mutex_lock(&disc->disc_mutex);
+	list_for_each_entry_safe(rdata, next, &disc->rports, peers) {
+		rport = PRIV_TO_RPORT(rdata);
+		list_del(&rdata->peers);
+		lport->tt.rport_logoff(rport);
+	}
+
+	mutex_unlock(&disc->disc_mutex);
+}
+
+/**
+ * fc_disc_rport_callback - Event handler for rport events
+ * @lport: The lport which is receiving the event
+ * @rport: The rport which the event has occured on
+ * @event: The event that occured
+ *
+ * Locking Note: The rport lock should not be held when calling
+ *		 this function.
+ */
+static void fc_disc_rport_callback(struct fc_lport *lport,
+				   struct fc_rport *rport,
+				   enum fc_rport_event event)
+{
+	struct fc_rport_libfc_priv *rdata = rport->dd_data;
+	struct fc_disc *disc = &lport->disc;
+	int found = 0;
+
+	FC_DEBUG_DISC("Received a %d event for port (%6x)\n", event,
+		      rport->port_id);
+
+	if (event == RPORT_EV_CREATED) {
+		if (disc) {
+			found = 1;
+			mutex_lock(&disc->disc_mutex);
+			list_add_tail(&rdata->peers, &disc->rports);
+			mutex_unlock(&disc->disc_mutex);
+		}
+	}
+
+	if (!found)
+		FC_DEBUG_DISC("The rport (%6x) is not maintained "
+			      "by the discovery layer\n", rport->port_id);
+}
+
+/**
+ * fc_disc_recv_rscn_req - Handle Registered State Change Notification (RSCN)
+ * @sp: Current sequence of the RSCN exchange
+ * @fp: RSCN Frame
+ * @lport: Fibre Channel host port instance
+ *
+ * Locking Note: This function expects that the disc_mutex is locked
+ *		 before it is called.
+ */
+static void fc_disc_recv_rscn_req(struct fc_seq *sp, struct fc_frame *fp,
+				  struct fc_disc *disc)
+{
+	struct fc_lport *lport;
+	struct fc_rport *rport;
+	struct fc_rport_libfc_priv *rdata;
+	struct fc_els_rscn *rp;
+	struct fc_els_rscn_page *pp;
+	struct fc_seq_els_data rjt_data;
+	unsigned int len;
+	int redisc = 0;
+	enum fc_els_rscn_ev_qual ev_qual;
+	enum fc_els_rscn_addr_fmt fmt;
+	LIST_HEAD(disc_ports);
+	struct fc_disc_port *dp, *next;
+
+	lport = disc->lport;
+
+	FC_DEBUG_DISC("Received an RSCN event on port (%6x)\n",
+		      fc_host_port_id(lport->host));
+
+	/* make sure the frame contains an RSCN message */
+	rp = fc_frame_payload_get(fp, sizeof(*rp));
+	if (!rp)
+		goto reject;
+	/* make sure the page length is as expected (4 bytes) */
+	if (rp->rscn_page_len != sizeof(*pp))
+		goto reject;
+	/* get the RSCN payload length */
+	len = ntohs(rp->rscn_plen);
+	if (len < sizeof(*rp))
+		goto reject;
+	/* make sure the frame contains the expected payload */
+	rp = fc_frame_payload_get(fp, len);
+	if (!rp)
+		goto reject;
+	/* payload must be a multiple of the RSCN page size */
+	len -= sizeof(*rp);
+	if (len % sizeof(*pp))
+		goto reject;
+
+	for (pp = (void *)(rp + 1); len > 0; len -= sizeof(*pp), pp++) {
+		ev_qual = pp->rscn_page_flags >> ELS_RSCN_EV_QUAL_BIT;
+		ev_qual &= ELS_RSCN_EV_QUAL_MASK;
+		fmt = pp->rscn_page_flags >> ELS_RSCN_ADDR_FMT_BIT;
+		fmt &= ELS_RSCN_ADDR_FMT_MASK;
+		/*
+		 * if we get an address format other than port
+		 * (area, domain, fabric), then do a full discovery
+		 */
+		switch (fmt) {
+		case ELS_ADDR_FMT_PORT:
+			FC_DEBUG_DISC("Port address format for port (%6x)\n",
+				      ntoh24(pp->rscn_fid));
+			dp = kzalloc(sizeof(*dp), GFP_KERNEL);
+			if (!dp) {
+				redisc = 1;
+				break;
+			}
+			dp->lp = lport;
+			dp->ids.port_id = ntoh24(pp->rscn_fid);
+			dp->ids.port_name = -1;
+			dp->ids.node_name = -1;
+			dp->ids.roles = FC_RPORT_ROLE_UNKNOWN;
+			list_add_tail(&dp->peers, &disc_ports);
+			break;
+		case ELS_ADDR_FMT_AREA:
+		case ELS_ADDR_FMT_DOM:
+		case ELS_ADDR_FMT_FAB:
+		default:
+			FC_DEBUG_DISC("Address format is (%d)\n", fmt);
+			redisc = 1;
+			break;
+		}
+	}
+	lport->tt.seq_els_rsp_send(sp, ELS_LS_ACC, NULL);
+	if (redisc) {
+		FC_DEBUG_DISC("RSCN received: rediscovering\n");
+		fc_disc_restart(disc);
+	} else {
+		FC_DEBUG_DISC("RSCN received: not rediscovering. "
+			      "redisc %d state %d in_prog %d\n",
+			      redisc, lport->state, disc->pending);
+		list_for_each_entry_safe(dp, next, &disc_ports, peers) {
+			list_del(&dp->peers);
+			rport = lport->tt.rport_lookup(lport, dp->ids.port_id);
+			if (rport) {
+				rdata = RPORT_TO_PRIV(rport);
+				list_del(&rdata->peers);
+				lport->tt.rport_logoff(rport);
+			}
+			fc_disc_single(disc, dp);
+		}
+	}
+	fc_frame_free(fp);
+	return;
+reject:
+	FC_DEBUG_DISC("Received a bad RSCN frame\n");
+	rjt_data.fp = NULL;
+	rjt_data.reason = ELS_RJT_LOGIC;
+	rjt_data.explan = ELS_EXPL_NONE;
+	lport->tt.seq_els_rsp_send(sp, ELS_LS_RJT, &rjt_data);
+	fc_frame_free(fp);
+}
+
+/**
+ * fc_disc_recv_req - Handle incoming requests
+ * @sp: Current sequence of the request exchange
+ * @fp: The frame
+ * @lport: The FC local port
+ *
+ * Locking Note: This function is called from the EM and will lock
+ *		 the disc_mutex before calling the handler for the
+ *		 request.
+ */
+static void fc_disc_recv_req(struct fc_seq *sp, struct fc_frame *fp,
+			     struct fc_lport *lport)
+{
+	u8 op;
+	struct fc_disc *disc = &lport->disc;
+
+	op = fc_frame_payload_op(fp);
+	switch (op) {
+	case ELS_RSCN:
+		mutex_lock(&disc->disc_mutex);
+		fc_disc_recv_rscn_req(sp, fp, disc);
+		mutex_unlock(&disc->disc_mutex);
+		break;
+	default:
+		FC_DBG("Received an unsupported request. opcode (%x)\n", op);
+		break;
+	}
+}
+
+/**
+ * fc_disc_restart - Restart discovery
+ * @lport: FC discovery context
+ *
+ * Locking Note: This function expects that the disc mutex
+ *		 is already locked.
+ */
+static void fc_disc_restart(struct fc_disc *disc)
+{
+	struct fc_rport *rport;
+	struct fc_rport_libfc_priv *rdata, *next;
+	struct fc_lport *lport = disc->lport;
+
+	FC_DEBUG_DISC("Restarting discovery for port (%6x)\n",
+		      fc_host_port_id(lport->host));
+
+	list_for_each_entry_safe(rdata, next, &disc->rports, peers) {
+		rport = PRIV_TO_RPORT(rdata);
+		FC_DEBUG_DISC("list_del(%6x)\n", rport->port_id);
+		list_del(&rdata->peers);
+		lport->tt.rport_logoff(rport);
+	}
+
+	disc->requested = 1;
+	if (!disc->pending)
+		fc_disc_gpn_ft_req(disc);
+}
+
+/**
+ * fc_disc_start - Fibre Channel Target discovery
+ * @lport: FC local port
+ *
+ * Returns non-zero if discovery cannot be started.
+ */
+static void fc_disc_start(void (*disc_callback)(struct fc_lport *,
+						enum fc_disc_event),
+			  struct fc_lport *lport)
+{
+	struct fc_rport *rport;
+	struct fc_rport_identifiers ids;
+	struct fc_disc *disc = &lport->disc;
+
+	/*
+	 * At this point we may have a new disc job or an existing
+	 * one. Either way, let's lock when we make changes to it
+	 * and send the GPN_FT request.
+	 */
+	mutex_lock(&disc->disc_mutex);
+
+	disc->disc_callback = disc_callback;
+
+	/*
+	 * If not ready, or already running discovery, just set request flag.
+	 */
+	disc->requested = 1;
+
+	if (disc->pending) {
+		mutex_unlock(&disc->disc_mutex);
+		return;
+	}
+
+	/*
+	 * Handle point-to-point mode as a simple discovery
+	 * of the remote port. Yucky, yucky, yuck, yuck!
+	 */
+	rport = disc->lport->ptp_rp;
+	if (rport) {
+		ids.port_id = rport->port_id;
+		ids.port_name = rport->port_name;
+		ids.node_name = rport->node_name;
+		ids.roles = FC_RPORT_ROLE_UNKNOWN;
+		get_device(&rport->dev);
+
+		if (!fc_disc_new_target(disc, rport, &ids)) {
+			disc->event = DISC_EV_SUCCESS;
+			fc_disc_done(disc);
+		}
+		put_device(&rport->dev);
+	} else {
+		fc_disc_gpn_ft_req(disc);	/* get ports by FC-4 type */
+	}
+
+	mutex_unlock(&disc->disc_mutex);
+}
+
+static struct fc_rport_operations fc_disc_rport_ops = {
+	.event_callback = fc_disc_rport_callback,
+};
+
+/**
+ * fc_disc_new_target - Handle new target found by discovery
+ * @lport: FC local port
+ * @rport: The previous FC remote port (NULL if new remote port)
+ * @ids: Identifiers for the new FC remote port
+ *
+ * Locking Note: This function expects that the disc_mutex is locked
+ *		 before it is called.
+ */
+static int fc_disc_new_target(struct fc_disc *disc,
+			      struct fc_rport *rport,
+			      struct fc_rport_identifiers *ids)
+{
+	struct fc_lport *lport = disc->lport;
+	struct fc_rport_libfc_priv *rp;
+	int error = 0;
+
+	if (rport && ids->port_name) {
+		if (rport->port_name == -1) {
+			/*
+			 * Set WWN and fall through to notify of create.
+			 */
+			fc_rport_set_name(rport, ids->port_name,
+					  rport->node_name);
+		} else if (rport->port_name != ids->port_name) {
+			/*
+			 * This is a new port with the same FCID as
+			 * a previously-discovered port.  Presumably the old
+			 * port logged out and a new port logged in and was
+			 * assigned the same FCID.  This should be rare.
+			 * Delete the old one and fall thru to re-create.
+			 */
+			fc_disc_del_target(disc, rport);
+			rport = NULL;
+		}
+	}
+	if (((ids->port_name != -1) || (ids->port_id != -1)) &&
+	    ids->port_id != fc_host_port_id(lport->host) &&
+	    ids->port_name != lport->wwpn) {
+		if (!rport) {
+			rport = lport->tt.rport_lookup(lport, ids->port_id);
+			if (!rport) {
+				struct fc_disc_port dp;
+				dp.lp = lport;
+				dp.ids.port_id = ids->port_id;
+				dp.ids.port_name = ids->port_name;
+				dp.ids.node_name = ids->node_name;
+				dp.ids.roles = ids->roles;
+				rport = fc_rport_rogue_create(&dp);
+			}
+			if (!rport)
+				error = -ENOMEM;
+		}
+		if (rport) {
+			rp = rport->dd_data;
+			rp->ops = &fc_disc_rport_ops;
+			rp->rp_state = RPORT_ST_INIT;
+			lport->tt.rport_login(rport);
+		}
+	}
+	return error;
+}
+
+/**
+ * fc_disc_del_target - Delete a target
+ * @disc: FC discovery context
+ * @rport: The remote port to be removed
+ */
+static void fc_disc_del_target(struct fc_disc *disc, struct fc_rport *rport)
+{
+	struct fc_lport *lport = disc->lport;
+	struct fc_rport_libfc_priv *rdata = RPORT_TO_PRIV(rport);
+	list_del(&rdata->peers);
+	lport->tt.rport_logoff(rport);
+}
+
+/**
+ * fc_disc_done - Discovery has been completed
+ * @disc: FC discovery context
+ */
+static void fc_disc_done(struct fc_disc *disc)
+{
+	struct fc_lport *lport = disc->lport;
+
+	FC_DEBUG_DISC("Discovery complete for port (%6x)\n",
+		      fc_host_port_id(lport->host));
+
+	disc->disc_callback(lport, disc->event);
+	disc->event = DISC_EV_NONE;
+
+	if (disc->requested)
+		fc_disc_gpn_ft_req(disc);
+	else
+		disc->pending = 0;
+}
+
+/**
+ * fc_disc_error - Handle error on dNS request
+ * @disc: FC discovery context
+ * @fp: The frame pointer
+ */
+static void fc_disc_error(struct fc_disc *disc, struct fc_frame *fp)
+{
+	struct fc_lport *lport = disc->lport;
+	unsigned long delay = 0;
+	if (fc_disc_debug)
+		FC_DBG("Error %ld, retries %d/%d\n",
+		       PTR_ERR(fp), disc->retry_count,
+		       FC_DISC_RETRY_LIMIT);
+
+	if (!fp || PTR_ERR(fp) == -FC_EX_TIMEOUT) {
+		/*
+		 * Memory allocation failure, or the exchange timed out,
+		 * retry after delay.
+		 */
+		if (disc->retry_count < FC_DISC_RETRY_LIMIT) {
+			/* go ahead and retry */
+			if (!fp)
+				delay = msecs_to_jiffies(FC_DISC_RETRY_DELAY);
+			else {
+				delay = msecs_to_jiffies(lport->e_d_tov);
+
+				/* timeout faster first time */
+				if (!disc->retry_count)
+					delay /= 4;
+			}
+			disc->retry_count++;
+			schedule_delayed_work(&disc->disc_work, delay);
+		} else {
+			/* exceeded retries */
+			disc->event = DISC_EV_FAILED;
+			fc_disc_done(disc);
+		}
+	}
+}
+
+/**
+ * fc_disc_gpn_ft_req - Send Get Port Names by FC-4 type (GPN_FT) request
+ * @lport: FC discovery context
+ *
+ * Locking Note: This function expects that the disc_mutex is locked
+ *		 before it is called.
+ */
+static void fc_disc_gpn_ft_req(struct fc_disc *disc)
+{
+	struct fc_frame *fp;
+	struct fc_lport *lport = disc->lport;
+
+	WARN_ON(!fc_lport_test_ready(lport));
+
+	disc->pending = 1;
+	disc->requested = 0;
+
+	disc->buf_len = 0;
+	disc->seq_count = 0;
+	fp = fc_frame_alloc(lport,
+			    sizeof(struct fc_ct_hdr) +
+			    sizeof(struct fc_ns_gid_ft));
+	if (!fp)
+		goto err;
+
+	if (lport->tt.elsct_send(lport, NULL, fp,
+				 FC_NS_GPN_FT,
+				 fc_disc_gpn_ft_resp,
+				 disc, lport->e_d_tov))
+		return;
+err:
+	fc_disc_error(disc, fp);
+}
+
+/**
+ * fc_disc_gpn_ft_parse - Parse the list of IDs and names resulting from a request
+ * @lport: Fibre Channel host port instance
+ * @buf: GPN_FT response buffer
+ * @len: size of response buffer
+ */
+static int fc_disc_gpn_ft_parse(struct fc_disc *disc, void *buf, size_t len)
+{
+	struct fc_lport *lport;
+	struct fc_gpn_ft_resp *np;
+	char *bp;
+	size_t plen;
+	size_t tlen;
+	int error = 0;
+	struct fc_disc_port dp;
+	struct fc_rport *rport;
+	struct fc_rport_libfc_priv *rdata;
+
+	lport = disc->lport;
+
+	/*
+	 * Handle partial name record left over from previous call.
+	 */
+	bp = buf;
+	plen = len;
+	np = (struct fc_gpn_ft_resp *)bp;
+	tlen = disc->buf_len;
+	if (tlen) {
+		WARN_ON(tlen >= sizeof(*np));
+		plen = sizeof(*np) - tlen;
+		WARN_ON(plen <= 0);
+		WARN_ON(plen >= sizeof(*np));
+		if (plen > len)
+			plen = len;
+		np = &disc->partial_buf;
+		memcpy((char *)np + tlen, bp, plen);
+
+		/*
+		 * Set bp so that the loop below will advance it to the
+		 * first valid full name element.
+		 */
+		bp -= tlen;
+		len += tlen;
+		plen += tlen;
+		disc->buf_len = (unsigned char) plen;
+		if (plen == sizeof(*np))
+			disc->buf_len = 0;
+	}
+
+	/*
+	 * Handle full name records, including the one filled from above.
+	 * Normally, np == bp and plen == len, but from the partial case above,
+	 * bp, len describe the overall buffer, and np, plen describe the
+	 * partial buffer, which if would usually be full now.
+	 * After the first time through the loop, things return to "normal".
+	 */
+	while (plen >= sizeof(*np)) {
+		dp.lp = lport;
+		dp.ids.port_id = ntoh24(np->fp_fid);
+		dp.ids.port_name = ntohll(np->fp_wwpn);
+		dp.ids.node_name = -1;
+		dp.ids.roles = FC_RPORT_ROLE_UNKNOWN;
+
+		if ((dp.ids.port_id != fc_host_port_id(lport->host)) &&
+		    (dp.ids.port_name != lport->wwpn)) {
+			rport = fc_rport_rogue_create(&dp);
+			if (rport) {
+				rdata = rport->dd_data;
+				rdata->ops = &fc_disc_rport_ops;
+				rdata->local_port = lport;
+				lport->tt.rport_login(rport);
+			} else
+				FC_DBG("Failed to allocate memory for "
+				       "the newly discovered port (%6x)\n",
+				       dp.ids.port_id);
+		}
+
+		if (np->fp_flags & FC_NS_FID_LAST) {
+			disc->event = DISC_EV_SUCCESS;
+			fc_disc_done(disc);
+			len = 0;
+			break;
+		}
+		len -= sizeof(*np);
+		bp += sizeof(*np);
+		np = (struct fc_gpn_ft_resp *)bp;
+		plen = len;
+	}
+
+	/*
+	 * Save any partial record at the end of the buffer for next time.
+	 */
+	if (error == 0 && len > 0 && len < sizeof(*np)) {
+		if (np != &disc->partial_buf) {
+			FC_DEBUG_DISC("Partial buffer remains "
+				      "for discovery by (%6x)\n",
+				      fc_host_port_id(lport->host));
+			memcpy(&disc->partial_buf, np, len);
+		}
+		disc->buf_len = (unsigned char) len;
+	} else {
+		disc->buf_len = 0;
+	}
+	return error;
+}
+
+/*
+ * Handle retry of memory allocation for remote ports.
+ */
+static void fc_disc_timeout(struct work_struct *work)
+{
+	struct fc_disc *disc = container_of(work,
+					    struct fc_disc,
+					    disc_work.work);
+	mutex_lock(&disc->disc_mutex);
+	if (disc->requested && !disc->pending)
+		fc_disc_gpn_ft_req(disc);
+	mutex_unlock(&disc->disc_mutex);
+}
+
+/**
+ * fc_disc_gpn_ft_resp - Handle a response frame from Get Port Names (GPN_FT)
+ * @sp: Current sequence of GPN_FT exchange
+ * @fp: response frame
+ * @lp_arg: Fibre Channel host port instance
+ *
+ * Locking Note: This function expects that the disc_mutex is locked
+ *		 before it is called.
+ */
+static void fc_disc_gpn_ft_resp(struct fc_seq *sp, struct fc_frame *fp,
+				void *disc_arg)
+{
+	struct fc_disc *disc = disc_arg;
+	struct fc_ct_hdr *cp;
+	struct fc_frame_header *fh;
+	unsigned int seq_cnt;
+	void *buf = NULL;
+	unsigned int len;
+	int error;
+
+	FC_DEBUG_DISC("Received a GPN_FT response on port (%6x)\n",
+		      fc_host_port_id(disc->lport->host));
+
+	if (IS_ERR(fp)) {
+		fc_disc_error(disc, fp);
+		return;
+	}
+
+	WARN_ON(!fc_frame_is_linear(fp));	/* buffer must be contiguous */
+	fh = fc_frame_header_get(fp);
+	len = fr_len(fp) - sizeof(*fh);
+	seq_cnt = ntohs(fh->fh_seq_cnt);
+	if (fr_sof(fp) == FC_SOF_I3 && seq_cnt == 0 &&
+	    disc->seq_count == 0) {
+		cp = fc_frame_payload_get(fp, sizeof(*cp));
+		if (!cp) {
+			FC_DBG("GPN_FT response too short, len %d\n",
+			       fr_len(fp));
+		} else if (ntohs(cp->ct_cmd) == FC_FS_ACC) {
+
+			/*
+			 * Accepted.  Parse response.
+			 */
+			buf = cp + 1;
+			len -= sizeof(*cp);
+		} else if (ntohs(cp->ct_cmd) == FC_FS_RJT) {
+			FC_DBG("GPN_FT rejected reason %x exp %x "
+			       "(check zoning)\n", cp->ct_reason,
+			       cp->ct_explan);
+			disc->event = DISC_EV_FAILED;
+			fc_disc_done(disc);
+		} else {
+			FC_DBG("GPN_FT unexpected response code %x\n",
+			       ntohs(cp->ct_cmd));
+		}
+	} else if (fr_sof(fp) == FC_SOF_N3 &&
+		   seq_cnt == disc->seq_count) {
+		buf = fh + 1;
+	} else {
+		FC_DBG("GPN_FT unexpected frame - out of sequence? "
+		       "seq_cnt %x expected %x sof %x eof %x\n",
+		       seq_cnt, disc->seq_count, fr_sof(fp), fr_eof(fp));
+	}
+	if (buf) {
+		error = fc_disc_gpn_ft_parse(disc, buf, len);
+		if (error)
+			fc_disc_error(disc, fp);
+		else
+			disc->seq_count++;
+	}
+	fc_frame_free(fp);
+}
+
+/**
+ * fc_disc_single - Discover the directory information for a single target
+ * @lport: FC local port
+ * @dp: The port to rediscover
+ *
+ * Locking Note: This function expects that the disc_mutex is locked
+ *		 before it is called.
+ */
+static void fc_disc_single(struct fc_disc *disc, struct fc_disc_port *dp)
+{
+	struct fc_lport *lport;
+	struct fc_rport *rport;
+	struct fc_rport *new_rport;
+	struct fc_rport_libfc_priv *rdata;
+
+	lport = disc->lport;
+
+	if (dp->ids.port_id == fc_host_port_id(lport->host))
+		goto out;
+
+	rport = lport->tt.rport_lookup(lport, dp->ids.port_id);
+	if (rport)
+		fc_disc_del_target(disc, rport);
+
+	new_rport = fc_rport_rogue_create(dp);
+	if (new_rport) {
+		rdata = new_rport->dd_data;
+		rdata->ops = &fc_disc_rport_ops;
+		kfree(dp);
+		lport->tt.rport_login(new_rport);
+	}
+	return;
+out:
+	kfree(dp);
+}
+
+/**
+ * fc_disc_stop - Stop discovery for a given lport
+ * @lport: The lport that discovery should stop for
+ */
+void fc_disc_stop(struct fc_lport *lport)
+{
+	struct fc_disc *disc = &lport->disc;
+
+	if (disc) {
+		cancel_delayed_work_sync(&disc->disc_work);
+		fc_disc_stop_rports(disc);
+	}
+}
+
+/**
+ * fc_disc_stop_final - Stop discovery for a given lport
+ * @lport: The lport that discovery should stop for
+ *
+ * This function will block until discovery has been
+ * completely stopped and all rports have been deleted.
+ */
+void fc_disc_stop_final(struct fc_lport *lport)
+{
+	fc_disc_stop(lport);
+	lport->tt.rport_flush_queue();
+}
+
+/**
+ * fc_disc_init - Initialize the discovery block
+ * @lport: FC local port
+ */
+int fc_disc_init(struct fc_lport *lport)
+{
+	struct fc_disc *disc;
+
+	if (!lport->tt.disc_start)
+		lport->tt.disc_start = fc_disc_start;
+
+	if (!lport->tt.disc_stop)
+		lport->tt.disc_stop = fc_disc_stop;
+
+	if (!lport->tt.disc_stop_final)
+		lport->tt.disc_stop_final = fc_disc_stop_final;
+
+	if (!lport->tt.disc_recv_req)
+		lport->tt.disc_recv_req = fc_disc_recv_req;
+
+	if (!lport->tt.rport_lookup)
+		lport->tt.rport_lookup = fc_disc_lookup_rport;
+
+	disc = &lport->disc;
+	INIT_DELAYED_WORK(&disc->disc_work, fc_disc_timeout);
+	mutex_init(&disc->disc_mutex);
+	INIT_LIST_HEAD(&disc->rports);
+
+	disc->lport = lport;
+	disc->delay = FC_DISC_DELAY;
+	disc->event = DISC_EV_NONE;
+
+	return 0;
+}
+EXPORT_SYMBOL(fc_disc_init);

drivers/scsi/libfc/fc_elsct.c

···
+/*
+ * Copyright(c) 2008 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Maintained at www.Open-FCoE.org
+ */
+
+/*
+ * Provide interface to send ELS/CT FC frames
+ */
+
+#include <asm/unaligned.h>
+#include <scsi/fc/fc_gs.h>
+#include <scsi/fc/fc_ns.h>
+#include <scsi/fc/fc_els.h>
+#include <scsi/libfc.h>
+#include <scsi/fc_encode.h>
+
+/*
+ * fc_elsct_send - sends ELS/CT frame
+ */
+static struct fc_seq *fc_elsct_send(struct fc_lport *lport,
+				    struct fc_rport *rport,
+				    struct fc_frame *fp,
+				    unsigned int op,
+				    void (*resp)(struct fc_seq *,
+						 struct fc_frame *fp,
+						 void *arg),
+				    void *arg, u32 timer_msec)
+{
+	enum fc_rctl r_ctl;
+	u32 did;
+	enum fc_fh_type fh_type;
+	int rc;
+
+	/* ELS requests */
+	if ((op >= ELS_LS_RJT) && (op <= ELS_AUTH_ELS))
+		rc = fc_els_fill(lport, rport, fp, op, &r_ctl, &did, &fh_type);
+	else
+		/* CT requests */
+		rc = fc_ct_fill(lport, fp, op, &r_ctl, &did, &fh_type);
+
+	if (rc)
+		return NULL;
+
+	fc_fill_fc_hdr(fp, r_ctl, did, fc_host_port_id(lport->host), fh_type,
+		       FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
+
+	return lport->tt.exch_seq_send(lport, fp, resp, NULL, arg, timer_msec);
+}
+
+int fc_elsct_init(struct fc_lport *lport)
+{
+	if (!lport->tt.elsct_send)
+		lport->tt.elsct_send = fc_elsct_send;
+
+	return 0;
+}
+EXPORT_SYMBOL(fc_elsct_init);

drivers/scsi/libfc/fc_exch.c

···
+/*
+ * Copyright(c) 2007 Intel Corporation. All rights reserved.
+ * Copyright(c) 2008 Red Hat, Inc.  All rights reserved.
+ * Copyright(c) 2008 Mike Christie
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Maintained at www.Open-FCoE.org
+ */
+
+/*
+ * Fibre Channel exchange and sequence handling.
+ */
+
+#include <linux/timer.h>
+#include <linux/gfp.h>
+#include <linux/err.h>
+
+#include <scsi/fc/fc_fc2.h>
+
+#include <scsi/libfc.h>
+#include <scsi/fc_encode.h>
+
+#define	  FC_DEF_R_A_TOV      (10 * 1000) /* resource allocation timeout */
+
+/*
+ * fc_exch_debug can be set in debugger or at compile time to get more logs.
+ */
+static int fc_exch_debug;
+
+#define FC_DEBUG_EXCH(fmt...)			\
+	do {					\
+		if (fc_exch_debug)		\
+			FC_DBG(fmt);		\
+	} while (0)
+
+static struct kmem_cache *fc_em_cachep;	/* cache for exchanges */
+
+/*
+ * Structure and function definitions for managing Fibre Channel Exchanges
+ * and Sequences.
+ *
+ * The three primary structures used here are fc_exch_mgr, fc_exch, and fc_seq.
+ *
+ * fc_exch_mgr holds the exchange state for an N port
+ *
+ * fc_exch holds state for one exchange and links to its active sequence.
+ *
+ * fc_seq holds the state for an individual sequence.
+ */
+
+/*
+ * Exchange manager.
+ *
+ * This structure is the center for creating exchanges and sequences.
+ * It manages the allocation of exchange IDs.
+ */
+struct fc_exch_mgr {
+	enum fc_class	class;		/* default class for sequences */
+	spinlock_t	em_lock;	/* exchange manager lock,
+					   must be taken before ex_lock */
+	u16		last_xid;	/* last allocated exchange ID */
+	u16		min_xid;	/* min exchange ID */
+	u16		max_xid;	/* max exchange ID */
+	u16		max_read;	/* max exchange ID for read */
+	u16		last_read;	/* last xid allocated for read */
+	u32	total_exches;		/* total allocated exchanges */
+	struct list_head	ex_list;	/* allocated exchanges list */
+	struct fc_lport	*lp;		/* fc device instance */
+	mempool_t	*ep_pool;	/* reserve ep's */
+
+	/*
+	 * currently exchange mgr stats are updated but not used.
+	 * either stats can be expose via sysfs or remove them
+	 * all together if not used XXX
+	 */
+	struct {
+		atomic_t no_free_exch;
+		atomic_t no_free_exch_xid;
+		atomic_t xid_not_found;
+		atomic_t xid_busy;
+		atomic_t seq_not_found;
+		atomic_t non_bls_resp;
+	} stats;
+	struct fc_exch **exches;	/* for exch pointers indexed by xid */
+};
+#define	fc_seq_exch(sp) container_of(sp, struct fc_exch, seq)
+
+static void fc_exch_rrq(struct fc_exch *);
+static void fc_seq_ls_acc(struct fc_seq *);
+static void fc_seq_ls_rjt(struct fc_seq *, enum fc_els_rjt_reason,
+			  enum fc_els_rjt_explan);
+static void fc_exch_els_rec(struct fc_seq *, struct fc_frame *);
+static void fc_exch_els_rrq(struct fc_seq *, struct fc_frame *);
+static struct fc_seq *fc_seq_start_next_locked(struct fc_seq *sp);
+
+/*
+ * Internal implementation notes.
+ *
+ * The exchange manager is one by default in libfc but LLD may choose
+ * to have one per CPU. The sequence manager is one per exchange manager
+ * and currently never separated.
+ *
+ * Section 9.8 in FC-FS-2 specifies:  "The SEQ_ID is a one-byte field
+ * assigned by the Sequence Initiator that shall be unique for a specific
+ * D_ID and S_ID pair while the Sequence is open."   Note that it isn't
+ * qualified by exchange ID, which one might think it would be.
+ * In practice this limits the number of open sequences and exchanges to 256
+ * per session.	 For most targets we could treat this limit as per exchange.
+ *
+ * The exchange and its sequence are freed when the last sequence is received.
+ * It's possible for the remote port to leave an exchange open without
+ * sending any sequences.
+ *
+ * Notes on reference counts:
+ *
+ * Exchanges are reference counted and exchange gets freed when the reference
+ * count becomes zero.
+ *
+ * Timeouts:
+ * Sequences are timed out for E_D_TOV and R_A_TOV.
+ *
+ * Sequence event handling:
+ *
+ * The following events may occur on initiator sequences:
+ *
+ *	Send.
+ *	    For now, the whole thing is sent.
+ *	Receive ACK
+ *	    This applies only to class F.
+ *	    The sequence is marked complete.
+ *	ULP completion.
+ *	    The upper layer calls fc_exch_done() when done
+ *	    with exchange and sequence tuple.
+ *	RX-inferred completion.
+ *	    When we receive the next sequence on the same exchange, we can
+ *	    retire the previous sequence ID.  (XXX not implemented).
+ *	Timeout.
+ *	    R_A_TOV frees the sequence ID.  If we're waiting for ACK,
+ *	    E_D_TOV causes abort and calls upper layer response handler
+ *	    with FC_EX_TIMEOUT error.
+ *	Receive RJT
+ *	    XXX defer.
+ *	Send ABTS
+ *	    On timeout.
+ *
+ * The following events may occur on recipient sequences:
+ *
+ *	Receive
+ *	    Allocate sequence for first frame received.
+ *	    Hold during receive handler.
+ *	    Release when final frame received.
+ *	    Keep status of last N of these for the ELS RES command.  XXX TBD.
+ *	Receive ABTS
+ *	    Deallocate sequence
+ *	Send RJT
+ *	    Deallocate
+ *
+ * For now, we neglect conditions where only part of a sequence was
+ * received or transmitted, or where out-of-order receipt is detected.
+ */
+
+/*
+ * Locking notes:
+ *
+ * The EM code run in a per-CPU worker thread.
+ *
+ * To protect against concurrency between a worker thread code and timers,
+ * sequence allocation and deallocation must be locked.
+ *  - exchange refcnt can be done atomicly without locks.
+ *  - sequence allocation must be locked by exch lock.
+ *  - If the em_lock and ex_lock must be taken at the same time, then the
+ *    em_lock must be taken before the ex_lock.
+ */
+
+/*
+ * opcode names for debugging.
+ */
+static char *fc_exch_rctl_names[] = FC_RCTL_NAMES_INIT;
+
+#define FC_TABLE_SIZE(x)   (sizeof(x) / sizeof(x[0]))
+
+static inline const char *fc_exch_name_lookup(unsigned int op, char **table,
+					      unsigned int max_index)
+{
+	const char *name = NULL;
+
+	if (op < max_index)
+		name = table[op];
+	if (!name)
+		name = "unknown";
+	return name;
+}
+
+static const char *fc_exch_rctl_name(unsigned int op)
+{
+	return fc_exch_name_lookup(op, fc_exch_rctl_names,
+				   FC_TABLE_SIZE(fc_exch_rctl_names));
+}
+
+/*
+ * Hold an exchange - keep it from being freed.
+ */
+static void fc_exch_hold(struct fc_exch *ep)
+{
+	atomic_inc(&ep->ex_refcnt);
+}
+
+/*
+ * setup fc hdr by initializing few more FC header fields and sof/eof.
+ * Initialized fields by this func:
+ *	- fh_ox_id, fh_rx_id, fh_seq_id, fh_seq_cnt
+ *	- sof and eof
+ */
+static void fc_exch_setup_hdr(struct fc_exch *ep, struct fc_frame *fp,
+			      u32 f_ctl)
+{
+	struct fc_frame_header *fh = fc_frame_header_get(fp);
+	u16 fill;
+
+	fr_sof(fp) = ep->class;
+	if (ep->seq.cnt)
+		fr_sof(fp) = fc_sof_normal(ep->class);
+
+	if (f_ctl & FC_FC_END_SEQ) {
+		fr_eof(fp) = FC_EOF_T;
+		if (fc_sof_needs_ack(ep->class))
+			fr_eof(fp) = FC_EOF_N;
+		/*
+		 * Form f_ctl.
+		 * The number of fill bytes to make the length a 4-byte
+		 * multiple is the low order 2-bits of the f_ctl.
+		 * The fill itself will have been cleared by the frame
+		 * allocation.
+		 * After this, the length will be even, as expected by
+		 * the transport.
+		 */
+		fill = fr_len(fp) & 3;
+		if (fill) {
+			fill = 4 - fill;
+			/* TODO, this may be a problem with fragmented skb */
+			skb_put(fp_skb(fp), fill);
+			hton24(fh->fh_f_ctl, f_ctl | fill);
+		}
+	} else {
+		WARN_ON(fr_len(fp) % 4 != 0);	/* no pad to non last frame */
+		fr_eof(fp) = FC_EOF_N;
+	}
+
+	/*
+	 * Initialize remainig fh fields
+	 * from fc_fill_fc_hdr
+	 */
+	fh->fh_ox_id = htons(ep->oxid);
+	fh->fh_rx_id = htons(ep->rxid);
+	fh->fh_seq_id = ep->seq.id;
+	fh->fh_seq_cnt = htons(ep->seq.cnt);
+}
+
+
+/*
+ * Release a reference to an exchange.
+ * If the refcnt goes to zero and the exchange is complete, it is freed.
+ */
+static void fc_exch_release(struct fc_exch *ep)
+{
+	struct fc_exch_mgr *mp;
+
+	if (atomic_dec_and_test(&ep->ex_refcnt)) {
+		mp = ep->em;
+		if (ep->destructor)
+			ep->destructor(&ep->seq, ep->arg);
+		if (ep->lp->tt.exch_put)
+			ep->lp->tt.exch_put(ep->lp, mp, ep->xid);
+		WARN_ON(!ep->esb_stat & ESB_ST_COMPLETE);
+		mempool_free(ep, mp->ep_pool);
+	}
+}
+
+static int fc_exch_done_locked(struct fc_exch *ep)
+{
+	int rc = 1;
+
+	/*
+	 * We must check for completion in case there are two threads
+	 * tyring to complete this. But the rrq code will reuse the
+	 * ep, and in that case we only clear the resp and set it as
+	 * complete, so it can be reused by the timer to send the rrq.
+	 */
+	ep->resp = NULL;
+	if (ep->state & FC_EX_DONE)
+		return rc;
+	ep->esb_stat |= ESB_ST_COMPLETE;
+
+	if (!(ep->esb_stat & ESB_ST_REC_QUAL)) {
+		ep->state |= FC_EX_DONE;
+		if (cancel_delayed_work(&ep->timeout_work))
+			atomic_dec(&ep->ex_refcnt); /* drop hold for timer */
+		rc = 0;
+	}
+	return rc;
+}
+
+static void fc_exch_mgr_delete_ep(struct fc_exch *ep)
+{
+	struct fc_exch_mgr *mp;
+
+	mp = ep->em;
+	spin_lock_bh(&mp->em_lock);
+	WARN_ON(mp->total_exches <= 0);
+	mp->total_exches--;
+	mp->exches[ep->xid - mp->min_xid] = NULL;
+	list_del(&ep->ex_list);
+	spin_unlock_bh(&mp->em_lock);
+	fc_exch_release(ep);	/* drop hold for exch in mp */
+}
+
+/*
+ * Internal version of fc_exch_timer_set - used with lock held.
+ */
+static inline void fc_exch_timer_set_locked(struct fc_exch *ep,
+					    unsigned int timer_msec)
+{
+	if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE))
+		return;
+
+	FC_DEBUG_EXCH("Exchange (%4x) timed out, notifying the upper layer\n",
+		      ep->xid);
+	if (schedule_delayed_work(&ep->timeout_work,
+				  msecs_to_jiffies(timer_msec)))
+		fc_exch_hold(ep);		/* hold for timer */
+}
+
+/*
+ * Set timer for an exchange.
+ * The time is a minimum delay in milliseconds until the timer fires.
+ * Used for upper level protocols to time out the exchange.
+ * The timer is cancelled when it fires or when the exchange completes.
+ * Returns non-zero if a timer couldn't be allocated.
+ */
+static void fc_exch_timer_set(struct fc_exch *ep, unsigned int timer_msec)
+{
+	spin_lock_bh(&ep->ex_lock);
+	fc_exch_timer_set_locked(ep, timer_msec);
+	spin_unlock_bh(&ep->ex_lock);
+}
+
+int fc_seq_exch_abort(const struct fc_seq *req_sp, unsigned int timer_msec)
+{
+	struct fc_seq *sp;
+	struct fc_exch *ep;
+	struct fc_frame *fp;
+	int error;
+
+	ep = fc_seq_exch(req_sp);
+
+	spin_lock_bh(&ep->ex_lock);
+	if (ep->esb_stat & (ESB_ST_COMPLETE | ESB_ST_ABNORMAL) ||
+	    ep->state & (FC_EX_DONE | FC_EX_RST_CLEANUP)) {
+		spin_unlock_bh(&ep->ex_lock);
+		return -ENXIO;
+	}
+
+	/*
+	 * Send the abort on a new sequence if possible.
+	 */
+	sp = fc_seq_start_next_locked(&ep->seq);
+	if (!sp) {
+		spin_unlock_bh(&ep->ex_lock);
+		return -ENOMEM;
+	}
+
+	ep->esb_stat |= ESB_ST_SEQ_INIT | ESB_ST_ABNORMAL;
+	if (timer_msec)
+		fc_exch_timer_set_locked(ep, timer_msec);
+	spin_unlock_bh(&ep->ex_lock);
+
+	/*
+	 * If not logged into the fabric, don't send ABTS but leave
+	 * sequence active until next timeout.
+	 */
+	if (!ep->sid)
+		return 0;
+
+	/*
+	 * Send an abort for the sequence that timed out.
+	 */
+	fp = fc_frame_alloc(ep->lp, 0);
+	if (fp) {
+		fc_fill_fc_hdr(fp, FC_RCTL_BA_ABTS, ep->did, ep->sid,
+			       FC_TYPE_BLS, FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
+		error = fc_seq_send(ep->lp, sp, fp);
+	} else
+		error = -ENOBUFS;
+	return error;
+}
+EXPORT_SYMBOL(fc_seq_exch_abort);
+
+/*
+ * Exchange timeout - handle exchange timer expiration.
+ * The timer will have been cancelled before this is called.
+ */
+static void fc_exch_timeout(struct work_struct *work)
+{
+	struct fc_exch *ep = container_of(work, struct fc_exch,
+					  timeout_work.work);
+	struct fc_seq *sp = &ep->seq;
+	void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
+	void *arg;
+	u32 e_stat;
+	int rc = 1;
+
+	spin_lock_bh(&ep->ex_lock);
+	if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE))
+		goto unlock;
+
+	e_stat = ep->esb_stat;
+	if (e_stat & ESB_ST_COMPLETE) {
+		ep->esb_stat = e_stat & ~ESB_ST_REC_QUAL;
+		if (e_stat & ESB_ST_REC_QUAL)
+			fc_exch_rrq(ep);
+		spin_unlock_bh(&ep->ex_lock);
+		goto done;
+	} else {
+		resp = ep->resp;
+		arg = ep->arg;
+		ep->resp = NULL;
+		if (e_stat & ESB_ST_ABNORMAL)
+			rc = fc_exch_done_locked(ep);
+		spin_unlock_bh(&ep->ex_lock);
+		if (!rc)
+			fc_exch_mgr_delete_ep(ep);
+		if (resp)
+			resp(sp, ERR_PTR(-FC_EX_TIMEOUT), arg);
+		fc_seq_exch_abort(sp, 2 * ep->r_a_tov);
+		goto done;
+	}
+unlock:
+	spin_unlock_bh(&ep->ex_lock);
+done:
+	/*
+	 * This release matches the hold taken when the timer was set.
+	 */
+	fc_exch_release(ep);
+}
+
+/*
+ * Allocate a sequence.
+ *
+ * We don't support multiple originated sequences on the same exchange.
+ * By implication, any previously originated sequence on this exchange
+ * is complete, and we reallocate the same sequence.
+ */
+static struct fc_seq *fc_seq_alloc(struct fc_exch *ep, u8 seq_id)
+{
+	struct fc_seq *sp;
+
+	sp = &ep->seq;
+	sp->ssb_stat = 0;
+	sp->cnt = 0;
+	sp->id = seq_id;
+	return sp;
+}
+
+/*
+ * fc_em_alloc_xid - returns an xid based on request type
+ * @lp : ptr to associated lport
+ * @fp : ptr to the assocated frame
+ *
+ * check the associated fc_fsp_pkt to get scsi command type and
+ * command direction to decide from which range this exch id
+ * will be allocated from.
+ *
+ * Returns : 0 or an valid xid
+ */
+static u16 fc_em_alloc_xid(struct fc_exch_mgr *mp, const struct fc_frame *fp)
+{
+	u16 xid, min, max;
+	u16 *plast;
+	struct fc_exch *ep = NULL;
+
+	if (mp->max_read) {
+		if (fc_frame_is_read(fp)) {
+			min = mp->min_xid;
+			max = mp->max_read;
+			plast = &mp->last_read;
+		} else {
+			min = mp->max_read + 1;
+			max = mp->max_xid;
+			plast = &mp->last_xid;
+		}
+	} else {
+		min = mp->min_xid;
+		max = mp->max_xid;
+		plast = &mp->last_xid;
+	}
+	xid = *plast;
+	do {
+		xid = (xid == max) ? min : xid + 1;
+		ep = mp->exches[xid - mp->min_xid];
+	} while ((ep != NULL) && (xid != *plast));
+
+	if (unlikely(ep))
+		xid = 0;
+	else
+		*plast = xid;
+
+	return xid;
+}
+
+/*
+ * fc_exch_alloc - allocate an exchange.
+ * @mp : ptr to the exchange manager
+ * @xid: input xid
+ *
+ * if xid is supplied zero then assign next free exchange ID
+ * from exchange manager, otherwise use supplied xid.
+ * Returns with exch lock held.
+ */
+struct fc_exch *fc_exch_alloc(struct fc_exch_mgr *mp,
+			      struct fc_frame *fp, u16 xid)
+{
+	struct fc_exch *ep;
+
+	/* allocate memory for exchange */
+	ep = mempool_alloc(mp->ep_pool, GFP_ATOMIC);
+	if (!ep) {
+		atomic_inc(&mp->stats.no_free_exch);
+		goto out;
+	}
+	memset(ep, 0, sizeof(*ep));
+
+	spin_lock_bh(&mp->em_lock);
+	/* alloc xid if input xid 0 */
+	if (!xid) {
+		/* alloc a new xid */
+		xid = fc_em_alloc_xid(mp, fp);
+		if (!xid) {
+			printk(KERN_ERR "fc_em_alloc_xid() failed\n");
+			goto err;
+		}
+	}
+
+	fc_exch_hold(ep);	/* hold for exch in mp */
+	spin_lock_init(&ep->ex_lock);
+	/*
+	 * Hold exch lock for caller to prevent fc_exch_reset()
+	 * from releasing exch	while fc_exch_alloc() caller is
+	 * still working on exch.
+	 */
+	spin_lock_bh(&ep->ex_lock);
+
+	mp->exches[xid - mp->min_xid] = ep;
+	list_add_tail(&ep->ex_list, &mp->ex_list);
+	fc_seq_alloc(ep, ep->seq_id++);
+	mp->total_exches++;
+	spin_unlock_bh(&mp->em_lock);
+
+	/*
+	 *  update exchange
+	 */
+	ep->oxid = ep->xid = xid;
+	ep->em = mp;
+	ep->lp = mp->lp;
+	ep->f_ctl = FC_FC_FIRST_SEQ;	/* next seq is first seq */
+	ep->rxid = FC_XID_UNKNOWN;
+	ep->class = mp->class;
+	INIT_DELAYED_WORK(&ep->timeout_work, fc_exch_timeout);
+out:
+	return ep;
+err:
+	spin_unlock_bh(&mp->em_lock);
+	atomic_inc(&mp->stats.no_free_exch_xid);
+	mempool_free(ep, mp->ep_pool);
+	return NULL;
+}
+EXPORT_SYMBOL(fc_exch_alloc);
+
+/*
+ * Lookup and hold an exchange.
+ */
+static struct fc_exch *fc_exch_find(struct fc_exch_mgr *mp, u16 xid)
+{
+	struct fc_exch *ep = NULL;
+
+	if ((xid >= mp->min_xid) && (xid <= mp->max_xid)) {
+		spin_lock_bh(&mp->em_lock);
+		ep = mp->exches[xid - mp->min_xid];
+		if (ep) {
+			fc_exch_hold(ep);
+			WARN_ON(ep->xid != xid);
+		}
+		spin_unlock_bh(&mp->em_lock);
+	}
+	return ep;
+}
+
+void fc_exch_done(struct fc_seq *sp)
+{
+	struct fc_exch *ep = fc_seq_exch(sp);
+	int rc;
+
+	spin_lock_bh(&ep->ex_lock);
+	rc = fc_exch_done_locked(ep);
+	spin_unlock_bh(&ep->ex_lock);
+	if (!rc)
+		fc_exch_mgr_delete_ep(ep);
+}
+EXPORT_SYMBOL(fc_exch_done);
+
+/*
+ * Allocate a new exchange as responder.
+ * Sets the responder ID in the frame header.
+ */
+static struct fc_exch *fc_exch_resp(struct fc_exch_mgr *mp, struct fc_frame *fp)
+{
+	struct fc_exch *ep;
+	struct fc_frame_header *fh;
+	u16 rxid;
+
+	ep = mp->lp->tt.exch_get(mp->lp, fp);
+	if (ep) {
+		ep->class = fc_frame_class(fp);
+
+		/*
+		 * Set EX_CTX indicating we're responding on this exchange.
+		 */
+		ep->f_ctl |= FC_FC_EX_CTX;	/* we're responding */
+		ep->f_ctl &= ~FC_FC_FIRST_SEQ;	/* not new */
+		fh = fc_frame_header_get(fp);
+		ep->sid = ntoh24(fh->fh_d_id);
+		ep->did = ntoh24(fh->fh_s_id);
+		ep->oid = ep->did;
+
+		/*
+		 * Allocated exchange has placed the XID in the
+		 * originator field. Move it to the responder field,
+		 * and set the originator XID from the frame.
+		 */
+		ep->rxid = ep->xid;
+		ep->oxid = ntohs(fh->fh_ox_id);
+		ep->esb_stat |= ESB_ST_RESP | ESB_ST_SEQ_INIT;
+		if ((ntoh24(fh->fh_f_ctl) & FC_FC_SEQ_INIT) == 0)
+			ep->esb_stat &= ~ESB_ST_SEQ_INIT;
+
+		/*
+		 * Set the responder ID in the frame header.
+		 * The old one should've been 0xffff.
+		 * If it isn't, don't assign one.
+		 * Incoming basic link service frames may specify
+		 * a referenced RX_ID.
+		 */
+		if (fh->fh_type != FC_TYPE_BLS) {
+			rxid = ntohs(fh->fh_rx_id);
+			WARN_ON(rxid != FC_XID_UNKNOWN);
+			fh->fh_rx_id = htons(ep->rxid);
+		}
+		fc_exch_hold(ep);	/* hold for caller */
+		spin_unlock_bh(&ep->ex_lock);	/* lock from exch_get */
+	}
+	return ep;
+}
+
+/*
+ * Find a sequence for receive where the other end is originating the sequence.
+ * If fc_pf_rjt_reason is FC_RJT_NONE then this function will have a hold
+ * on the ep that should be released by the caller.
+ */
+static enum fc_pf_rjt_reason
+fc_seq_lookup_recip(struct fc_exch_mgr *mp, struct fc_frame *fp)
+{
+	struct fc_frame_header *fh = fc_frame_header_get(fp);
+	struct fc_exch *ep = NULL;
+	struct fc_seq *sp = NULL;
+	enum fc_pf_rjt_reason reject = FC_RJT_NONE;
+	u32 f_ctl;
+	u16 xid;
+
+	f_ctl = ntoh24(fh->fh_f_ctl);
+	WARN_ON((f_ctl & FC_FC_SEQ_CTX) != 0);
+
+	/*
+	 * Lookup or create the exchange if we will be creating the sequence.
+	 */
+	if (f_ctl & FC_FC_EX_CTX) {
+		xid = ntohs(fh->fh_ox_id);	/* we originated exch */
+		ep = fc_exch_find(mp, xid);
+		if (!ep) {
+			atomic_inc(&mp->stats.xid_not_found);
+			reject = FC_RJT_OX_ID;
+			goto out;
+		}
+		if (ep->rxid == FC_XID_UNKNOWN)
+			ep->rxid = ntohs(fh->fh_rx_id);
+		else if (ep->rxid != ntohs(fh->fh_rx_id)) {
+			reject = FC_RJT_OX_ID;
+			goto rel;
+		}
+	} else {
+		xid = ntohs(fh->fh_rx_id);	/* we are the responder */
+
+		/*
+		 * Special case for MDS issuing an ELS TEST with a
+		 * bad rxid of 0.
+		 * XXX take this out once we do the proper reject.
+		 */
+		if (xid == 0 && fh->fh_r_ctl == FC_RCTL_ELS_REQ &&
+		    fc_frame_payload_op(fp) == ELS_TEST) {
+			fh->fh_rx_id = htons(FC_XID_UNKNOWN);
+			xid = FC_XID_UNKNOWN;
+		}
+
+		/*
+		 * new sequence - find the exchange
+		 */
+		ep = fc_exch_find(mp, xid);
+		if ((f_ctl & FC_FC_FIRST_SEQ) && fc_sof_is_init(fr_sof(fp))) {
+			if (ep) {
+				atomic_inc(&mp->stats.xid_busy);
+				reject = FC_RJT_RX_ID;
+				goto rel;
+			}
+			ep = fc_exch_resp(mp, fp);
+			if (!ep) {
+				reject = FC_RJT_EXCH_EST;	/* XXX */
+				goto out;
+			}
+			xid = ep->xid;	/* get our XID */
+		} else if (!ep) {
+			atomic_inc(&mp->stats.xid_not_found);
+			reject = FC_RJT_RX_ID;	/* XID not found */
+			goto out;
+		}
+	}
+
+	/*
+	 * At this point, we have the exchange held.
+	 * Find or create the sequence.
+	 */
+	if (fc_sof_is_init(fr_sof(fp))) {
+		sp = fc_seq_start_next(&ep->seq);
+		if (!sp) {
+			reject = FC_RJT_SEQ_XS;	/* exchange shortage */
+			goto rel;
+		}
+		sp->id = fh->fh_seq_id;
+		sp->ssb_stat |= SSB_ST_RESP;
+	} else {
+		sp = &ep->seq;
+		if (sp->id != fh->fh_seq_id) {
+			atomic_inc(&mp->stats.seq_not_found);
+			reject = FC_RJT_SEQ_ID;	/* sequence/exch should exist */
+			goto rel;
+		}
+	}
+	WARN_ON(ep != fc_seq_exch(sp));
+
+	if (f_ctl & FC_FC_SEQ_INIT)
+		ep->esb_stat |= ESB_ST_SEQ_INIT;
+
+	fr_seq(fp) = sp;
+out:
+	return reject;
+rel:
+	fc_exch_done(&ep->seq);
+	fc_exch_release(ep);	/* hold from fc_exch_find/fc_exch_resp */
+	return reject;
+}
+
+/*
+ * Find the sequence for a frame being received.
+ * We originated the sequence, so it should be found.
+ * We may or may not have originated the exchange.
+ * Does not hold the sequence for the caller.
+ */
+static struct fc_seq *fc_seq_lookup_orig(struct fc_exch_mgr *mp,
+					 struct fc_frame *fp)
+{
+	struct fc_frame_header *fh = fc_frame_header_get(fp);
+	struct fc_exch *ep;
+	struct fc_seq *sp = NULL;
+	u32 f_ctl;
+	u16 xid;
+
+	f_ctl = ntoh24(fh->fh_f_ctl);
+	WARN_ON((f_ctl & FC_FC_SEQ_CTX) != FC_FC_SEQ_CTX);
+	xid = ntohs((f_ctl & FC_FC_EX_CTX) ? fh->fh_ox_id : fh->fh_rx_id);
+	ep = fc_exch_find(mp, xid);
+	if (!ep)
+		return NULL;
+	if (ep->seq.id == fh->fh_seq_id) {
+		/*
+		 * Save the RX_ID if we didn't previously know it.
+		 */
+		sp = &ep->seq;
+		if ((f_ctl & FC_FC_EX_CTX) != 0 &&
+		    ep->rxid == FC_XID_UNKNOWN) {
+			ep->rxid = ntohs(fh->fh_rx_id);
+		}
+	}
+	fc_exch_release(ep);
+	return sp;
+}
+
+/*
+ * Set addresses for an exchange.
+ * Note this must be done before the first sequence of the exchange is sent.
+ */
+static void fc_exch_set_addr(struct fc_exch *ep,
+			     u32 orig_id, u32 resp_id)
+{
+	ep->oid = orig_id;
+	if (ep->esb_stat & ESB_ST_RESP) {
+		ep->sid = resp_id;
+		ep->did = orig_id;
+	} else {
+		ep->sid = orig_id;
+		ep->did = resp_id;
+	}
+}
+
+static struct fc_seq *fc_seq_start_next_locked(struct fc_seq *sp)
+{
+	struct fc_exch *ep = fc_seq_exch(sp);
+
+	sp = fc_seq_alloc(ep, ep->seq_id++);
+	FC_DEBUG_EXCH("exch %4x f_ctl %6x seq %2x\n",
+		      ep->xid, ep->f_ctl, sp->id);
+	return sp;
+}
+/*
+ * Allocate a new sequence on the same exchange as the supplied sequence.
+ * This will never return NULL.
+ */
+struct fc_seq *fc_seq_start_next(struct fc_seq *sp)
+{
+	struct fc_exch *ep = fc_seq_exch(sp);
+
+	spin_lock_bh(&ep->ex_lock);
+	WARN_ON((ep->esb_stat & ESB_ST_COMPLETE) != 0);
+	sp = fc_seq_start_next_locked(sp);
+	spin_unlock_bh(&ep->ex_lock);
+
+	return sp;
+}
+EXPORT_SYMBOL(fc_seq_start_next);
+
+int fc_seq_send(struct fc_lport *lp, struct fc_seq *sp, struct fc_frame *fp)
+{
+	struct fc_exch *ep;
+	struct fc_frame_header *fh = fc_frame_header_get(fp);
+	int error;
+	u32	f_ctl;
+
+	ep = fc_seq_exch(sp);
+	WARN_ON((ep->esb_stat & ESB_ST_SEQ_INIT) != ESB_ST_SEQ_INIT);
+
+	f_ctl = ntoh24(fh->fh_f_ctl);
+	fc_exch_setup_hdr(ep, fp, f_ctl);
+
+	/*
+	 * update sequence count if this frame is carrying
+	 * multiple FC frames when sequence offload is enabled
+	 * by LLD.
+	 */
+	if (fr_max_payload(fp))
+		sp->cnt += DIV_ROUND_UP((fr_len(fp) - sizeof(*fh)),
+					fr_max_payload(fp));
+	else
+		sp->cnt++;
+
+	/*
+	 * Send the frame.
+	 */
+	error = lp->tt.frame_send(lp, fp);
+
+	/*
+	 * Update the exchange and sequence flags,
+	 * assuming all frames for the sequence have been sent.
+	 * We can only be called to send once for each sequence.
+	 */
+	spin_lock_bh(&ep->ex_lock);
+	ep->f_ctl = f_ctl & ~FC_FC_FIRST_SEQ;	/* not first seq */
+	if (f_ctl & (FC_FC_END_SEQ | FC_FC_SEQ_INIT))
+		ep->esb_stat &= ~ESB_ST_SEQ_INIT;
+	spin_unlock_bh(&ep->ex_lock);
+	return error;
+}
+EXPORT_SYMBOL(fc_seq_send);
+
+void fc_seq_els_rsp_send(struct fc_seq *sp, enum fc_els_cmd els_cmd,
+			 struct fc_seq_els_data *els_data)
+{
+	switch (els_cmd) {
+	case ELS_LS_RJT:
+		fc_seq_ls_rjt(sp, els_data->reason, els_data->explan);
+		break;
+	case ELS_LS_ACC:
+		fc_seq_ls_acc(sp);
+		break;
+	case ELS_RRQ:
+		fc_exch_els_rrq(sp, els_data->fp);
+		break;
+	case ELS_REC:
+		fc_exch_els_rec(sp, els_data->fp);
+		break;
+	default:
+		FC_DBG("Invalid ELS CMD:%x\n", els_cmd);
+	}
+}
+EXPORT_SYMBOL(fc_seq_els_rsp_send);
+
+/*
+ * Send a sequence, which is also the last sequence in the exchange.
+ */
+static void fc_seq_send_last(struct fc_seq *sp, struct fc_frame *fp,
+			     enum fc_rctl rctl, enum fc_fh_type fh_type)
+{
+	u32 f_ctl;
+	struct fc_exch *ep = fc_seq_exch(sp);
+
+	f_ctl = FC_FC_LAST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT;
+	f_ctl |= ep->f_ctl;
+	fc_fill_fc_hdr(fp, rctl, ep->did, ep->sid, fh_type, f_ctl, 0);
+	fc_seq_send(ep->lp, sp, fp);
+}
+
+/*
+ * Send ACK_1 (or equiv.) indicating we received something.
+ * The frame we're acking is supplied.
+ */
+static void fc_seq_send_ack(struct fc_seq *sp, const struct fc_frame *rx_fp)
+{
+	struct fc_frame *fp;
+	struct fc_frame_header *rx_fh;
+	struct fc_frame_header *fh;
+	struct fc_exch *ep = fc_seq_exch(sp);
+	struct fc_lport *lp = ep->lp;
+	unsigned int f_ctl;
+
+	/*
+	 * Don't send ACKs for class 3.
+	 */
+	if (fc_sof_needs_ack(fr_sof(rx_fp))) {
+		fp = fc_frame_alloc(lp, 0);
+		if (!fp)
+			return;
+
+		fh = fc_frame_header_get(fp);
+		fh->fh_r_ctl = FC_RCTL_ACK_1;
+		fh->fh_type = FC_TYPE_BLS;
+
+		/*
+		 * Form f_ctl by inverting EX_CTX and SEQ_CTX (bits 23, 22).
+		 * Echo FIRST_SEQ, LAST_SEQ, END_SEQ, END_CONN, SEQ_INIT.
+		 * Bits 9-8 are meaningful (retransmitted or unidirectional).
+		 * Last ACK uses bits 7-6 (continue sequence),
+		 * bits 5-4 are meaningful (what kind of ACK to use).
+		 */
+		rx_fh = fc_frame_header_get(rx_fp);
+		f_ctl = ntoh24(rx_fh->fh_f_ctl);
+		f_ctl &= FC_FC_EX_CTX | FC_FC_SEQ_CTX |
+			FC_FC_FIRST_SEQ | FC_FC_LAST_SEQ |
+			FC_FC_END_SEQ | FC_FC_END_CONN | FC_FC_SEQ_INIT |
+			FC_FC_RETX_SEQ | FC_FC_UNI_TX;
+		f_ctl ^= FC_FC_EX_CTX | FC_FC_SEQ_CTX;
+		hton24(fh->fh_f_ctl, f_ctl);
+
+		fc_exch_setup_hdr(ep, fp, f_ctl);
+		fh->fh_seq_id = rx_fh->fh_seq_id;
+		fh->fh_seq_cnt = rx_fh->fh_seq_cnt;
+		fh->fh_parm_offset = htonl(1);	/* ack single frame */
+
+		fr_sof(fp) = fr_sof(rx_fp);
+		if (f_ctl & FC_FC_END_SEQ)
+			fr_eof(fp) = FC_EOF_T;
+		else
+			fr_eof(fp) = FC_EOF_N;
+
+		(void) lp->tt.frame_send(lp, fp);
+	}
+}
+
+/*
+ * Send BLS Reject.
+ * This is for rejecting BA_ABTS only.
+ */
+static void
+fc_exch_send_ba_rjt(struct fc_frame *rx_fp, enum fc_ba_rjt_reason reason,
+		    enum fc_ba_rjt_explan explan)
+{
+	struct fc_frame *fp;
+	struct fc_frame_header *rx_fh;
+	struct fc_frame_header *fh;
+	struct fc_ba_rjt *rp;
+	struct fc_lport *lp;
+	unsigned int f_ctl;
+
+	lp = fr_dev(rx_fp);
+	fp = fc_frame_alloc(lp, sizeof(*rp));
+	if (!fp)
+		return;
+	fh = fc_frame_header_get(fp);
+	rx_fh = fc_frame_header_get(rx_fp);
+
+	memset(fh, 0, sizeof(*fh) + sizeof(*rp));
+
+	rp = fc_frame_payload_get(fp, sizeof(*rp));
+	rp->br_reason = reason;
+	rp->br_explan = explan;
+
+	/*
+	 * seq_id, cs_ctl, df_ctl and param/offset are zero.
+	 */
+	memcpy(fh->fh_s_id, rx_fh->fh_d_id, 3);
+	memcpy(fh->fh_d_id, rx_fh->fh_s_id, 3);
+	fh->fh_ox_id = rx_fh->fh_rx_id;
+	fh->fh_rx_id = rx_fh->fh_ox_id;
+	fh->fh_seq_cnt = rx_fh->fh_seq_cnt;
+	fh->fh_r_ctl = FC_RCTL_BA_RJT;
+	fh->fh_type = FC_TYPE_BLS;
+
+	/*
+	 * Form f_ctl by inverting EX_CTX and SEQ_CTX (bits 23, 22).
+	 * Echo FIRST_SEQ, LAST_SEQ, END_SEQ, END_CONN, SEQ_INIT.
+	 * Bits 9-8 are meaningful (retransmitted or unidirectional).
+	 * Last ACK uses bits 7-6 (continue sequence),
+	 * bits 5-4 are meaningful (what kind of ACK to use).
+	 * Always set LAST_SEQ, END_SEQ.
+	 */
+	f_ctl = ntoh24(rx_fh->fh_f_ctl);
+	f_ctl &= FC_FC_EX_CTX | FC_FC_SEQ_CTX |
+		FC_FC_END_CONN | FC_FC_SEQ_INIT |
+		FC_FC_RETX_SEQ | FC_FC_UNI_TX;
+	f_ctl ^= FC_FC_EX_CTX | FC_FC_SEQ_CTX;
+	f_ctl |= FC_FC_LAST_SEQ | FC_FC_END_SEQ;
+	f_ctl &= ~FC_FC_FIRST_SEQ;
+	hton24(fh->fh_f_ctl, f_ctl);
+
+	fr_sof(fp) = fc_sof_class(fr_sof(rx_fp));
+	fr_eof(fp) = FC_EOF_T;
+	if (fc_sof_needs_ack(fr_sof(fp)))
+		fr_eof(fp) = FC_EOF_N;
+
+	(void) lp->tt.frame_send(lp, fp);
+}
+
+/*
+ * Handle an incoming ABTS.  This would be for target mode usually,
+ * but could be due to lost FCP transfer ready, confirm or RRQ.
+ * We always handle this as an exchange abort, ignoring the parameter.
+ */
+static void fc_exch_recv_abts(struct fc_exch *ep, struct fc_frame *rx_fp)
+{
+	struct fc_frame *fp;
+	struct fc_ba_acc *ap;
+	struct fc_frame_header *fh;
+	struct fc_seq *sp;
+
+	if (!ep)
+		goto reject;
+	spin_lock_bh(&ep->ex_lock);
+	if (ep->esb_stat & ESB_ST_COMPLETE) {
+		spin_unlock_bh(&ep->ex_lock);
+		goto reject;
+	}
+	if (!(ep->esb_stat & ESB_ST_REC_QUAL))
+		fc_exch_hold(ep);		/* hold for REC_QUAL */
+	ep->esb_stat |= ESB_ST_ABNORMAL | ESB_ST_REC_QUAL;
+	fc_exch_timer_set_locked(ep, ep->r_a_tov);
+
+	fp = fc_frame_alloc(ep->lp, sizeof(*ap));
+	if (!fp) {
+		spin_unlock_bh(&ep->ex_lock);
+		goto free;
+	}
+	fh = fc_frame_header_get(fp);
+	ap = fc_frame_payload_get(fp, sizeof(*ap));
+	memset(ap, 0, sizeof(*ap));
+	sp = &ep->seq;
+	ap->ba_high_seq_cnt = htons(0xffff);
+	if (sp->ssb_stat & SSB_ST_RESP) {
+		ap->ba_seq_id = sp->id;
+		ap->ba_seq_id_val = FC_BA_SEQ_ID_VAL;
+		ap->ba_high_seq_cnt = fh->fh_seq_cnt;
+		ap->ba_low_seq_cnt = htons(sp->cnt);
+	}
+	sp = fc_seq_start_next(sp);
+	spin_unlock_bh(&ep->ex_lock);
+	fc_seq_send_last(sp, fp, FC_RCTL_BA_ACC, FC_TYPE_BLS);
+	fc_frame_free(rx_fp);
+	return;
+
+reject:
+	fc_exch_send_ba_rjt(rx_fp, FC_BA_RJT_UNABLE, FC_BA_RJT_INV_XID);
+free:
+	fc_frame_free(rx_fp);
+}
+
+/*
+ * Handle receive where the other end is originating the sequence.
+ */
+static void fc_exch_recv_req(struct fc_lport *lp, struct fc_exch_mgr *mp,
+			     struct fc_frame *fp)
+{
+	struct fc_frame_header *fh = fc_frame_header_get(fp);
+	struct fc_seq *sp = NULL;
+	struct fc_exch *ep = NULL;
+	enum fc_sof sof;
+	enum fc_eof eof;
+	u32 f_ctl;
+	enum fc_pf_rjt_reason reject;
+
+	fr_seq(fp) = NULL;
+	reject = fc_seq_lookup_recip(mp, fp);
+	if (reject == FC_RJT_NONE) {
+		sp = fr_seq(fp);	/* sequence will be held */
+		ep = fc_seq_exch(sp);
+		sof = fr_sof(fp);
+		eof = fr_eof(fp);
+		f_ctl = ntoh24(fh->fh_f_ctl);
+		fc_seq_send_ack(sp, fp);
+
+		/*
+		 * Call the receive function.
+		 *
+		 * The receive function may allocate a new sequence
+		 * over the old one, so we shouldn't change the
+		 * sequence after this.
+		 *
+		 * The frame will be freed by the receive function.
+		 * If new exch resp handler is valid then call that
+		 * first.
+		 */
+		if (ep->resp)
+			ep->resp(sp, fp, ep->arg);
+		else
+			lp->tt.lport_recv(lp, sp, fp);
+		fc_exch_release(ep);	/* release from lookup */
+	} else {
+		FC_DEBUG_EXCH("exch/seq lookup failed: reject %x\n", reject);
+		fc_frame_free(fp);
+	}
+}
+
+/*
+ * Handle receive where the other end is originating the sequence in
+ * response to our exchange.
+ */
+static void fc_exch_recv_seq_resp(struct fc_exch_mgr *mp, struct fc_frame *fp)
+{
+	struct fc_frame_header *fh = fc_frame_header_get(fp);
+	struct fc_seq *sp;
+	struct fc_exch *ep;
+	enum fc_sof sof;
+	u32 f_ctl;
+	void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
+	void *ex_resp_arg;
+	int rc;
+
+	ep = fc_exch_find(mp, ntohs(fh->fh_ox_id));
+	if (!ep) {
+		atomic_inc(&mp->stats.xid_not_found);
+		goto out;
+	}
+	if (ep->rxid == FC_XID_UNKNOWN)
+		ep->rxid = ntohs(fh->fh_rx_id);
+	if (ep->sid != 0 && ep->sid != ntoh24(fh->fh_d_id)) {
+		atomic_inc(&mp->stats.xid_not_found);
+		goto rel;
+	}
+	if (ep->did != ntoh24(fh->fh_s_id) &&
+	    ep->did != FC_FID_FLOGI) {
+		atomic_inc(&mp->stats.xid_not_found);
+		goto rel;
+	}
+	sof = fr_sof(fp);
+	if (fc_sof_is_init(sof)) {
+		sp = fc_seq_start_next(&ep->seq);
+		sp->id = fh->fh_seq_id;
+		sp->ssb_stat |= SSB_ST_RESP;
+	} else {
+		sp = &ep->seq;
+		if (sp->id != fh->fh_seq_id) {
+			atomic_inc(&mp->stats.seq_not_found);
+			goto rel;
+		}
+	}
+	f_ctl = ntoh24(fh->fh_f_ctl);
+	fr_seq(fp) = sp;
+	if (f_ctl & FC_FC_SEQ_INIT)
+		ep->esb_stat |= ESB_ST_SEQ_INIT;
+
+	if (fc_sof_needs_ack(sof))
+		fc_seq_send_ack(sp, fp);
+	resp = ep->resp;
+	ex_resp_arg = ep->arg;
+
+	if (fh->fh_type != FC_TYPE_FCP && fr_eof(fp) == FC_EOF_T &&
+	    (f_ctl & (FC_FC_LAST_SEQ | FC_FC_END_SEQ)) ==
+	    (FC_FC_LAST_SEQ | FC_FC_END_SEQ)) {
+		spin_lock_bh(&ep->ex_lock);
+		rc = fc_exch_done_locked(ep);
+		WARN_ON(fc_seq_exch(sp) != ep);
+		spin_unlock_bh(&ep->ex_lock);
+		if (!rc)
+			fc_exch_mgr_delete_ep(ep);
+	}
+
+	/*
+	 * Call the receive function.
+	 * The sequence is held (has a refcnt) for us,
+	 * but not for the receive function.
+	 *
+	 * The receive function may allocate a new sequence
+	 * over the old one, so we shouldn't change the
+	 * sequence after this.
+	 *
+	 * The frame will be freed by the receive function.
+	 * If new exch resp handler is valid then call that
+	 * first.
+	 */
+	if (resp)
+		resp(sp, fp, ex_resp_arg);
+	else
+		fc_frame_free(fp);
+	fc_exch_release(ep);
+	return;
+rel:
+	fc_exch_release(ep);
+out:
+	fc_frame_free(fp);
+}
+
+/*
+ * Handle receive for a sequence where other end is responding to our sequence.
+ */
+static void fc_exch_recv_resp(struct fc_exch_mgr *mp, struct fc_frame *fp)
+{
+	struct fc_seq *sp;
+
+	sp = fc_seq_lookup_orig(mp, fp);	/* doesn't hold sequence */
+	if (!sp) {
+		atomic_inc(&mp->stats.xid_not_found);
+		FC_DEBUG_EXCH("seq lookup failed\n");
+	} else {
+		atomic_inc(&mp->stats.non_bls_resp);
+		FC_DEBUG_EXCH("non-BLS response to sequence");
+	}
+	fc_frame_free(fp);
+}
+
+/*
+ * Handle the response to an ABTS for exchange or sequence.
+ * This can be BA_ACC or BA_RJT.
+ */
+static void fc_exch_abts_resp(struct fc_exch *ep, struct fc_frame *fp)
+{
+	void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
+	void *ex_resp_arg;
+	struct fc_frame_header *fh;
+	struct fc_ba_acc *ap;
+	struct fc_seq *sp;
+	u16 low;
+	u16 high;
+	int rc = 1, has_rec = 0;
+
+	fh = fc_frame_header_get(fp);
+	FC_DEBUG_EXCH("exch: BLS rctl %x - %s\n",
+		      fh->fh_r_ctl, fc_exch_rctl_name(fh->fh_r_ctl));
+
+	if (cancel_delayed_work_sync(&ep->timeout_work))
+		fc_exch_release(ep);	/* release from pending timer hold */
+
+	spin_lock_bh(&ep->ex_lock);
+	switch (fh->fh_r_ctl) {
+	case FC_RCTL_BA_ACC:
+		ap = fc_frame_payload_get(fp, sizeof(*ap));
+		if (!ap)
+			break;
+
+		/*
+		 * Decide whether to establish a Recovery Qualifier.
+		 * We do this if there is a non-empty SEQ_CNT range and
+		 * SEQ_ID is the same as the one we aborted.
+		 */
+		low = ntohs(ap->ba_low_seq_cnt);
+		high = ntohs(ap->ba_high_seq_cnt);
+		if ((ep->esb_stat & ESB_ST_REC_QUAL) == 0 &&
+		    (ap->ba_seq_id_val != FC_BA_SEQ_ID_VAL ||
+		     ap->ba_seq_id == ep->seq_id) && low != high) {
+			ep->esb_stat |= ESB_ST_REC_QUAL;
+			fc_exch_hold(ep);  /* hold for recovery qualifier */
+			has_rec = 1;
+		}
+		break;
+	case FC_RCTL_BA_RJT:
+		break;
+	default:
+		break;
+	}
+
+	resp = ep->resp;
+	ex_resp_arg = ep->arg;
+
+	/* do we need to do some other checks here. Can we reuse more of
+	 * fc_exch_recv_seq_resp
+	 */
+	sp = &ep->seq;
+	/*
+	 * do we want to check END_SEQ as well as LAST_SEQ here?
+	 */
+	if (ep->fh_type != FC_TYPE_FCP &&
+	    ntoh24(fh->fh_f_ctl) & FC_FC_LAST_SEQ)
+		rc = fc_exch_done_locked(ep);
+	spin_unlock_bh(&ep->ex_lock);
+	if (!rc)
+		fc_exch_mgr_delete_ep(ep);
+
+	if (resp)
+		resp(sp, fp, ex_resp_arg);
+	else
+		fc_frame_free(fp);
+
+	if (has_rec)
+		fc_exch_timer_set(ep, ep->r_a_tov);
+
+}
+
+/*
+ * Receive BLS sequence.
+ * This is always a sequence initiated by the remote side.
+ * We may be either the originator or recipient of the exchange.
+ */
+static void fc_exch_recv_bls(struct fc_exch_mgr *mp, struct fc_frame *fp)
+{
+	struct fc_frame_header *fh;
+	struct fc_exch *ep;
+	u32 f_ctl;
+
+	fh = fc_frame_header_get(fp);
+	f_ctl = ntoh24(fh->fh_f_ctl);
+	fr_seq(fp) = NULL;
+
+	ep = fc_exch_find(mp, (f_ctl & FC_FC_EX_CTX) ?
+			  ntohs(fh->fh_ox_id) : ntohs(fh->fh_rx_id));
+	if (ep && (f_ctl & FC_FC_SEQ_INIT)) {
+		spin_lock_bh(&ep->ex_lock);
+		ep->esb_stat |= ESB_ST_SEQ_INIT;
+		spin_unlock_bh(&ep->ex_lock);
+	}
+	if (f_ctl & FC_FC_SEQ_CTX) {
+		/*
+		 * A response to a sequence we initiated.
+		 * This should only be ACKs for class 2 or F.
+		 */
+		switch (fh->fh_r_ctl) {
+		case FC_RCTL_ACK_1:
+		case FC_RCTL_ACK_0:
+			break;
+		default:
+			FC_DEBUG_EXCH("BLS rctl %x - %s received",
+				      fh->fh_r_ctl,
+				      fc_exch_rctl_name(fh->fh_r_ctl));
+			break;
+		}
+		fc_frame_free(fp);
+	} else {
+		switch (fh->fh_r_ctl) {
+		case FC_RCTL_BA_RJT:
+		case FC_RCTL_BA_ACC:
+			if (ep)
+				fc_exch_abts_resp(ep, fp);
+			else
+				fc_frame_free(fp);
+			break;
+		case FC_RCTL_BA_ABTS:
+			fc_exch_recv_abts(ep, fp);
+			break;
+		default:			/* ignore junk */
+			fc_frame_free(fp);
+			break;
+		}
+	}
+	if (ep)
+		fc_exch_release(ep);	/* release hold taken by fc_exch_find */
+}
+
+/*
+ * Accept sequence with LS_ACC.
+ * If this fails due to allocation or transmit congestion, assume the
+ * originator will repeat the sequence.
+ */
+static void fc_seq_ls_acc(struct fc_seq *req_sp)
+{
+	struct fc_seq *sp;
+	struct fc_els_ls_acc *acc;
+	struct fc_frame *fp;
+
+	sp = fc_seq_start_next(req_sp);
+	fp = fc_frame_alloc(fc_seq_exch(sp)->lp, sizeof(*acc));
+	if (fp) {
+		acc = fc_frame_payload_get(fp, sizeof(*acc));
+		memset(acc, 0, sizeof(*acc));
+		acc->la_cmd = ELS_LS_ACC;
+		fc_seq_send_last(sp, fp, FC_RCTL_ELS_REP, FC_TYPE_ELS);
+	}
+}
+
+/*
+ * Reject sequence with ELS LS_RJT.
+ * If this fails due to allocation or transmit congestion, assume the
+ * originator will repeat the sequence.
+ */
+static void fc_seq_ls_rjt(struct fc_seq *req_sp, enum fc_els_rjt_reason reason,
+			  enum fc_els_rjt_explan explan)
+{
+	struct fc_seq *sp;
+	struct fc_els_ls_rjt *rjt;
+	struct fc_frame *fp;
+
+	sp = fc_seq_start_next(req_sp);
+	fp = fc_frame_alloc(fc_seq_exch(sp)->lp, sizeof(*rjt));
+	if (fp) {
+		rjt = fc_frame_payload_get(fp, sizeof(*rjt));
+		memset(rjt, 0, sizeof(*rjt));
+		rjt->er_cmd = ELS_LS_RJT;
+		rjt->er_reason = reason;
+		rjt->er_explan = explan;
+		fc_seq_send_last(sp, fp, FC_RCTL_ELS_REP, FC_TYPE_ELS);
+	}
+}
+
+static void fc_exch_reset(struct fc_exch *ep)
+{
+	struct fc_seq *sp;
+	void (*resp)(struct fc_seq *, struct fc_frame *, void *);
+	void *arg;
+	int rc = 1;
+
+	spin_lock_bh(&ep->ex_lock);
+	ep->state |= FC_EX_RST_CLEANUP;
+	/*
+	 * we really want to call del_timer_sync, but cannot due
+	 * to the lport calling with the lport lock held (some resp
+	 * functions can also grab the lport lock which could cause
+	 * a deadlock).
+	 */
+	if (cancel_delayed_work(&ep->timeout_work))
+		atomic_dec(&ep->ex_refcnt);	/* drop hold for timer */
+	resp = ep->resp;
+	ep->resp = NULL;
+	if (ep->esb_stat & ESB_ST_REC_QUAL)
+		atomic_dec(&ep->ex_refcnt);	/* drop hold for rec_qual */
+	ep->esb_stat &= ~ESB_ST_REC_QUAL;
+	arg = ep->arg;
+	sp = &ep->seq;
+	rc = fc_exch_done_locked(ep);
+	spin_unlock_bh(&ep->ex_lock);
+	if (!rc)
+		fc_exch_mgr_delete_ep(ep);
+
+	if (resp)
+		resp(sp, ERR_PTR(-FC_EX_CLOSED), arg);
+}
+
+/*
+ * Reset an exchange manager, releasing all sequences and exchanges.
+ * If sid is non-zero, reset only exchanges we source from that FID.
+ * If did is non-zero, reset only exchanges destined to that FID.
+ */
+void fc_exch_mgr_reset(struct fc_exch_mgr *mp, u32 sid, u32 did)
+{
+	struct fc_exch *ep;
+	struct fc_exch *next;
+
+	spin_lock_bh(&mp->em_lock);
+restart:
+	list_for_each_entry_safe(ep, next, &mp->ex_list, ex_list) {
+		if ((sid == 0 || sid == ep->sid) &&
+		    (did == 0 || did == ep->did)) {
+			fc_exch_hold(ep);
+			spin_unlock_bh(&mp->em_lock);
+
+			fc_exch_reset(ep);
+
+			fc_exch_release(ep);
+			spin_lock_bh(&mp->em_lock);
+
+			/*
+			 * must restart loop incase while lock was down
+			 * multiple eps were released.
+			 */
+			goto restart;
+		}
+	}
+	spin_unlock_bh(&mp->em_lock);
+}
+EXPORT_SYMBOL(fc_exch_mgr_reset);
+
+/*
+ * Handle incoming ELS REC - Read Exchange Concise.
+ * Note that the requesting port may be different than the S_ID in the request.
+ */
+static void fc_exch_els_rec(struct fc_seq *sp, struct fc_frame *rfp)
+{
+	struct fc_frame *fp;
+	struct fc_exch *ep;
+	struct fc_exch_mgr *em;
+	struct fc_els_rec *rp;
+	struct fc_els_rec_acc *acc;
+	enum fc_els_rjt_reason reason = ELS_RJT_LOGIC;
+	enum fc_els_rjt_explan explan;
+	u32 sid;
+	u16 rxid;
+	u16 oxid;
+
+	rp = fc_frame_payload_get(rfp, sizeof(*rp));
+	explan = ELS_EXPL_INV_LEN;
+	if (!rp)
+		goto reject;
+	sid = ntoh24(rp->rec_s_id);
+	rxid = ntohs(rp->rec_rx_id);
+	oxid = ntohs(rp->rec_ox_id);
+
+	/*
+	 * Currently it's hard to find the local S_ID from the exchange
+	 * manager.  This will eventually be fixed, but for now it's easier
+	 * to lookup the subject exchange twice, once as if we were
+	 * the initiator, and then again if we weren't.
+	 */
+	em = fc_seq_exch(sp)->em;
+	ep = fc_exch_find(em, oxid);
+	explan = ELS_EXPL_OXID_RXID;
+	if (ep && ep->oid == sid) {
+		if (ep->rxid != FC_XID_UNKNOWN &&
+		    rxid != FC_XID_UNKNOWN &&
+		    ep->rxid != rxid)
+			goto rel;
+	} else {
+		if (ep)
+			fc_exch_release(ep);
+		ep = NULL;
+		if (rxid != FC_XID_UNKNOWN)
+			ep = fc_exch_find(em, rxid);
+		if (!ep)
+			goto reject;
+	}
+
+	fp = fc_frame_alloc(fc_seq_exch(sp)->lp, sizeof(*acc));
+	if (!fp) {
+		fc_exch_done(sp);
+		goto out;
+	}
+	sp = fc_seq_start_next(sp);
+	acc = fc_frame_payload_get(fp, sizeof(*acc));
+	memset(acc, 0, sizeof(*acc));
+	acc->reca_cmd = ELS_LS_ACC;
+	acc->reca_ox_id = rp->rec_ox_id;
+	memcpy(acc->reca_ofid, rp->rec_s_id, 3);
+	acc->reca_rx_id = htons(ep->rxid);
+	if (ep->sid == ep->oid)
+		hton24(acc->reca_rfid, ep->did);
+	else
+		hton24(acc->reca_rfid, ep->sid);
+	acc->reca_fc4value = htonl(ep->seq.rec_data);
+	acc->reca_e_stat = htonl(ep->esb_stat & (ESB_ST_RESP |
+						 ESB_ST_SEQ_INIT |
+						 ESB_ST_COMPLETE));
+	sp = fc_seq_start_next(sp);
+	fc_seq_send_last(sp, fp, FC_RCTL_ELS_REP, FC_TYPE_ELS);
+out:
+	fc_exch_release(ep);
+	fc_frame_free(rfp);
+	return;
+
+rel:
+	fc_exch_release(ep);
+reject:
+	fc_seq_ls_rjt(sp, reason, explan);
+	fc_frame_free(rfp);
+}
+
+/*
+ * Handle response from RRQ.
+ * Not much to do here, really.
+ * Should report errors.
+ *
+ * TODO: fix error handler.
+ */
+static void fc_exch_rrq_resp(struct fc_seq *sp, struct fc_frame *fp, void *arg)
+{
+	struct fc_exch *aborted_ep = arg;
+	unsigned int op;
+
+	if (IS_ERR(fp)) {
+		int err = PTR_ERR(fp);
+
+		if (err == -FC_EX_CLOSED)
+			goto cleanup;
+		FC_DBG("Cannot process RRQ, because of frame error %d\n", err);
+		return;
+	}
+
+	op = fc_frame_payload_op(fp);
+	fc_frame_free(fp);
+
+	switch (op) {
+	case ELS_LS_RJT:
+		FC_DBG("LS_RJT for RRQ");
+		/* fall through */
+	case ELS_LS_ACC:
+		goto cleanup;
+	default:
+		FC_DBG("unexpected response op %x for RRQ", op);
+		return;
+	}
+
+cleanup:
+	fc_exch_done(&aborted_ep->seq);
+	/* drop hold for rec qual */
+	fc_exch_release(aborted_ep);
+}
+
+/*
+ * Send ELS RRQ - Reinstate Recovery Qualifier.
+ * This tells the remote port to stop blocking the use of
+ * the exchange and the seq_cnt range.
+ */
+static void fc_exch_rrq(struct fc_exch *ep)
+{
+	struct fc_lport *lp;
+	struct fc_els_rrq *rrq;
+	struct fc_frame *fp;
+	struct fc_seq *rrq_sp;
+	u32 did;
+
+	lp = ep->lp;
+
+	fp = fc_frame_alloc(lp, sizeof(*rrq));
+	if (!fp)
+		return;
+	rrq = fc_frame_payload_get(fp, sizeof(*rrq));
+	memset(rrq, 0, sizeof(*rrq));
+	rrq->rrq_cmd = ELS_RRQ;
+	hton24(rrq->rrq_s_id, ep->sid);
+	rrq->rrq_ox_id = htons(ep->oxid);
+	rrq->rrq_rx_id = htons(ep->rxid);
+
+	did = ep->did;
+	if (ep->esb_stat & ESB_ST_RESP)
+		did = ep->sid;
+
+	fc_fill_fc_hdr(fp, FC_RCTL_ELS_REQ, did,
+		       fc_host_port_id(lp->host), FC_TYPE_ELS,
+		       FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
+
+	rrq_sp = fc_exch_seq_send(lp, fp, fc_exch_rrq_resp, NULL, ep,
+				  lp->e_d_tov);
+	if (!rrq_sp) {
+		ep->esb_stat |= ESB_ST_REC_QUAL;
+		fc_exch_timer_set_locked(ep, ep->r_a_tov);
+		return;
+	}
+}
+
+
+/*
+ * Handle incoming ELS RRQ - Reset Recovery Qualifier.
+ */
+static void fc_exch_els_rrq(struct fc_seq *sp, struct fc_frame *fp)
+{
+	struct fc_exch *ep;		/* request or subject exchange */
+	struct fc_els_rrq *rp;
+	u32 sid;
+	u16 xid;
+	enum fc_els_rjt_explan explan;
+
+	rp = fc_frame_payload_get(fp, sizeof(*rp));
+	explan = ELS_EXPL_INV_LEN;
+	if (!rp)
+		goto reject;
+
+	/*
+	 * lookup subject exchange.
+	 */
+	ep = fc_seq_exch(sp);
+	sid = ntoh24(rp->rrq_s_id);		/* subject source */
+	xid = ep->did == sid ? ntohs(rp->rrq_ox_id) : ntohs(rp->rrq_rx_id);
+	ep = fc_exch_find(ep->em, xid);
+
+	explan = ELS_EXPL_OXID_RXID;
+	if (!ep)
+		goto reject;
+	spin_lock_bh(&ep->ex_lock);
+	if (ep->oxid != ntohs(rp->rrq_ox_id))
+		goto unlock_reject;
+	if (ep->rxid != ntohs(rp->rrq_rx_id) &&
+	    ep->rxid != FC_XID_UNKNOWN)
+		goto unlock_reject;
+	explan = ELS_EXPL_SID;
+	if (ep->sid != sid)
+		goto unlock_reject;
+
+	/*
+	 * Clear Recovery Qualifier state, and cancel timer if complete.
+	 */
+	if (ep->esb_stat & ESB_ST_REC_QUAL) {
+		ep->esb_stat &= ~ESB_ST_REC_QUAL;
+		atomic_dec(&ep->ex_refcnt);	/* drop hold for rec qual */
+	}
+	if (ep->esb_stat & ESB_ST_COMPLETE) {
+		if (cancel_delayed_work(&ep->timeout_work))
+			atomic_dec(&ep->ex_refcnt);	/* drop timer hold */
+	}
+
+	spin_unlock_bh(&ep->ex_lock);
+
+	/*
+	 * Send LS_ACC.
+	 */
+	fc_seq_ls_acc(sp);
+	fc_frame_free(fp);
+	return;
+
+unlock_reject:
+	spin_unlock_bh(&ep->ex_lock);
+	fc_exch_release(ep);	/* drop hold from fc_exch_find */
+reject:
+	fc_seq_ls_rjt(sp, ELS_RJT_LOGIC, explan);
+	fc_frame_free(fp);
+}
+
+struct fc_exch_mgr *fc_exch_mgr_alloc(struct fc_lport *lp,
+				      enum fc_class class,
+				      u16 min_xid, u16 max_xid)
+{
+	struct fc_exch_mgr *mp;
+	size_t len;
+
+	if (max_xid <= min_xid || min_xid == 0 || max_xid == FC_XID_UNKNOWN) {
+		FC_DBG("Invalid min_xid 0x:%x and max_xid 0x:%x\n",
+		       min_xid, max_xid);
+		return NULL;
+	}
+
+	/*
+	 * Memory need for EM
+	 */
+#define xid_ok(i, m1, m2) (((i) >= (m1)) && ((i) <= (m2)))
+	len = (max_xid - min_xid + 1) * (sizeof(struct fc_exch *));
+	len += sizeof(struct fc_exch_mgr);
+
+	mp = kzalloc(len, GFP_ATOMIC);
+	if (!mp)
+		return NULL;
+
+	mp->class = class;
+	mp->total_exches = 0;
+	mp->exches = (struct fc_exch **)(mp + 1);
+	mp->lp = lp;
+	/* adjust em exch xid range for offload */
+	mp->min_xid = min_xid;
+	mp->max_xid = max_xid;
+	mp->last_xid = min_xid - 1;
+	mp->max_read = 0;
+	mp->last_read = 0;
+	if (lp->lro_enabled && xid_ok(lp->lro_xid, min_xid, max_xid)) {
+		mp->max_read = lp->lro_xid;
+		mp->last_read = min_xid - 1;
+		mp->last_xid = mp->max_read;
+	} else {
+		/* disable lro if no xid control over read */
+		lp->lro_enabled = 0;
+	}
+
+	INIT_LIST_HEAD(&mp->ex_list);
+	spin_lock_init(&mp->em_lock);
+
+	mp->ep_pool = mempool_create_slab_pool(2, fc_em_cachep);
+	if (!mp->ep_pool)
+		goto free_mp;
+
+	return mp;
+
+free_mp:
+	kfree(mp);
+	return NULL;
+}
+EXPORT_SYMBOL(fc_exch_mgr_alloc);
+
+void fc_exch_mgr_free(struct fc_exch_mgr *mp)
+{
+	WARN_ON(!mp);
+	/*
+	 * The total exch count must be zero
+	 * before freeing exchange manager.
+	 */
+	WARN_ON(mp->total_exches != 0);
+	mempool_destroy(mp->ep_pool);
+	kfree(mp);
+}
+EXPORT_SYMBOL(fc_exch_mgr_free);
+
+struct fc_exch *fc_exch_get(struct fc_lport *lp, struct fc_frame *fp)
+{
+	if (!lp || !lp->emp)
+		return NULL;
+
+	return fc_exch_alloc(lp->emp, fp, 0);
+}
+EXPORT_SYMBOL(fc_exch_get);
+
+struct fc_seq *fc_exch_seq_send(struct fc_lport *lp,
+				struct fc_frame *fp,
+				void (*resp)(struct fc_seq *,
+					     struct fc_frame *fp,
+					     void *arg),
+				void (*destructor)(struct fc_seq *, void *),
+				void *arg, u32 timer_msec)
+{
+	struct fc_exch *ep;
+	struct fc_seq *sp = NULL;
+	struct fc_frame_header *fh;
+	int rc = 1;
+
+	ep = lp->tt.exch_get(lp, fp);
+	if (!ep) {
+		fc_frame_free(fp);
+		return NULL;
+	}
+	ep->esb_stat |= ESB_ST_SEQ_INIT;
+	fh = fc_frame_header_get(fp);
+	fc_exch_set_addr(ep, ntoh24(fh->fh_s_id), ntoh24(fh->fh_d_id));
+	ep->resp = resp;
+	ep->destructor = destructor;
+	ep->arg = arg;
+	ep->r_a_tov = FC_DEF_R_A_TOV;
+	ep->lp = lp;
+	sp = &ep->seq;
+
+	ep->fh_type = fh->fh_type; /* save for possbile timeout handling */
+	ep->f_ctl = ntoh24(fh->fh_f_ctl);
+	fc_exch_setup_hdr(ep, fp, ep->f_ctl);
+	sp->cnt++;
+
+	if (unlikely(lp->tt.frame_send(lp, fp)))
+		goto err;
+
+	if (timer_msec)
+		fc_exch_timer_set_locked(ep, timer_msec);
+	ep->f_ctl &= ~FC_FC_FIRST_SEQ;	/* not first seq */
+
+	if (ep->f_ctl & FC_FC_SEQ_INIT)
+		ep->esb_stat &= ~ESB_ST_SEQ_INIT;
+	spin_unlock_bh(&ep->ex_lock);
+	return sp;
+err:
+	rc = fc_exch_done_locked(ep);
+	spin_unlock_bh(&ep->ex_lock);
+	if (!rc)
+		fc_exch_mgr_delete_ep(ep);
+	return NULL;
+}
+EXPORT_SYMBOL(fc_exch_seq_send);
+
+/*
+ * Receive a frame
+ */
+void fc_exch_recv(struct fc_lport *lp, struct fc_exch_mgr *mp,
+		  struct fc_frame *fp)
+{
+	struct fc_frame_header *fh = fc_frame_header_get(fp);
+	u32 f_ctl;
+
+	/* lport lock ? */
+	if (!lp || !mp || (lp->state == LPORT_ST_NONE)) {
+		FC_DBG("fc_lport or EM is not allocated and configured");
+		fc_frame_free(fp);
+		return;
+	}
+
+	/*
+	 * If frame is marked invalid, just drop it.
+	 */
+	f_ctl = ntoh24(fh->fh_f_ctl);
+	switch (fr_eof(fp)) {
+	case FC_EOF_T:
+		if (f_ctl & FC_FC_END_SEQ)
+			skb_trim(fp_skb(fp), fr_len(fp) - FC_FC_FILL(f_ctl));
+		/* fall through */
+	case FC_EOF_N:
+		if (fh->fh_type == FC_TYPE_BLS)
+			fc_exch_recv_bls(mp, fp);
+		else if ((f_ctl & (FC_FC_EX_CTX | FC_FC_SEQ_CTX)) ==
+			 FC_FC_EX_CTX)
+			fc_exch_recv_seq_resp(mp, fp);
+		else if (f_ctl & FC_FC_SEQ_CTX)
+			fc_exch_recv_resp(mp, fp);
+		else
+			fc_exch_recv_req(lp, mp, fp);
+		break;
+	default:
+		FC_DBG("dropping invalid frame (eof %x)", fr_eof(fp));
+		fc_frame_free(fp);
+		break;
+	}
+}
+EXPORT_SYMBOL(fc_exch_recv);
+
+int fc_exch_init(struct fc_lport *lp)
+{
+	if (!lp->tt.exch_get) {
+		/*
+		 *  exch_put() should be NULL if
+		 *  exch_get() is NULL
+		 */
+		WARN_ON(lp->tt.exch_put);
+		lp->tt.exch_get = fc_exch_get;
+	}
+
+	if (!lp->tt.seq_start_next)
+		lp->tt.seq_start_next = fc_seq_start_next;
+
+	if (!lp->tt.exch_seq_send)
+		lp->tt.exch_seq_send = fc_exch_seq_send;
+
+	if (!lp->tt.seq_send)
+		lp->tt.seq_send = fc_seq_send;
+
+	if (!lp->tt.seq_els_rsp_send)
+		lp->tt.seq_els_rsp_send = fc_seq_els_rsp_send;
+
+	if (!lp->tt.exch_done)
+		lp->tt.exch_done = fc_exch_done;
+
+	if (!lp->tt.exch_mgr_reset)
+		lp->tt.exch_mgr_reset = fc_exch_mgr_reset;
+
+	if (!lp->tt.seq_exch_abort)
+		lp->tt.seq_exch_abort = fc_seq_exch_abort;
+
+	return 0;
+}
+EXPORT_SYMBOL(fc_exch_init);
+
+int fc_setup_exch_mgr(void)
+{
+	fc_em_cachep = kmem_cache_create("libfc_em", sizeof(struct fc_exch),
+					 0, SLAB_HWCACHE_ALIGN, NULL);
+	if (!fc_em_cachep)
+		return -ENOMEM;
+	return 0;
+}
+
+void fc_destroy_exch_mgr(void)
+{
+	kmem_cache_destroy(fc_em_cachep);
+}

drivers/scsi/libfc/fc_fcp.c

···
+/*
+ * Copyright(c) 2007 Intel Corporation. All rights reserved.
+ * Copyright(c) 2008 Red Hat, Inc.  All rights reserved.
+ * Copyright(c) 2008 Mike Christie
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Maintained at www.Open-FCoE.org
+ */
+
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/spinlock.h>
+#include <linux/scatterlist.h>
+#include <linux/err.h>
+#include <linux/crc32.h>
+
+#include <scsi/scsi_tcq.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_cmnd.h>
+
+#include <scsi/fc/fc_fc2.h>
+
+#include <scsi/libfc.h>
+#include <scsi/fc_encode.h>
+
+MODULE_AUTHOR("Open-FCoE.org");
+MODULE_DESCRIPTION("libfc");
+MODULE_LICENSE("GPL");
+
+static int fc_fcp_debug;
+
+#define FC_DEBUG_FCP(fmt...)			\
+	do {					\
+		if (fc_fcp_debug)		\
+			FC_DBG(fmt);		\
+	} while (0)
+
+static struct kmem_cache *scsi_pkt_cachep;
+
+/* SRB state definitions */
+#define FC_SRB_FREE		0		/* cmd is free */
+#define FC_SRB_CMD_SENT		(1 << 0)	/* cmd has been sent */
+#define FC_SRB_RCV_STATUS	(1 << 1)	/* response has arrived */
+#define FC_SRB_ABORT_PENDING	(1 << 2)	/* cmd abort sent to device */
+#define FC_SRB_ABORTED		(1 << 3)	/* abort acknowleged */
+#define FC_SRB_DISCONTIG	(1 << 4)	/* non-sequential data recvd */
+#define FC_SRB_COMPL		(1 << 5)	/* fc_io_compl has been run */
+#define FC_SRB_FCP_PROCESSING_TMO (1 << 6)	/* timer function processing */
+#define FC_SRB_NOMEM		(1 << 7)	/* dropped to out of mem */
+
+#define FC_SRB_READ		(1 << 1)
+#define FC_SRB_WRITE		(1 << 0)
+
+/*
+ * The SCp.ptr should be tested and set under the host lock. NULL indicates
+ * that the command has been retruned to the scsi layer.
+ */
+#define CMD_SP(Cmnd)		    ((struct fc_fcp_pkt *)(Cmnd)->SCp.ptr)
+#define CMD_ENTRY_STATUS(Cmnd)	    ((Cmnd)->SCp.have_data_in)
+#define CMD_COMPL_STATUS(Cmnd)	    ((Cmnd)->SCp.this_residual)
+#define CMD_SCSI_STATUS(Cmnd)	    ((Cmnd)->SCp.Status)
+#define CMD_RESID_LEN(Cmnd)	    ((Cmnd)->SCp.buffers_residual)
+
+struct fc_fcp_internal {
+	mempool_t	*scsi_pkt_pool;
+	struct list_head scsi_pkt_queue;
+	u8		throttled;
+};
+
+#define fc_get_scsi_internal(x)	((struct fc_fcp_internal *)(x)->scsi_priv)
+
+/*
+ * function prototypes
+ * FC scsi I/O related functions
+ */
+static void fc_fcp_recv_data(struct fc_fcp_pkt *, struct fc_frame *);
+static void fc_fcp_recv(struct fc_seq *, struct fc_frame *, void *);
+static void fc_fcp_resp(struct fc_fcp_pkt *, struct fc_frame *);
+static void fc_fcp_complete_locked(struct fc_fcp_pkt *);
+static void fc_tm_done(struct fc_seq *, struct fc_frame *, void *);
+static void fc_fcp_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp);
+static void fc_timeout_error(struct fc_fcp_pkt *);
+static void fc_fcp_timeout(unsigned long data);
+static void fc_fcp_rec(struct fc_fcp_pkt *);
+static void fc_fcp_rec_error(struct fc_fcp_pkt *, struct fc_frame *);
+static void fc_fcp_rec_resp(struct fc_seq *, struct fc_frame *, void *);
+static void fc_io_compl(struct fc_fcp_pkt *);
+
+static void fc_fcp_srr(struct fc_fcp_pkt *, enum fc_rctl, u32);
+static void fc_fcp_srr_resp(struct fc_seq *, struct fc_frame *, void *);
+static void fc_fcp_srr_error(struct fc_fcp_pkt *, struct fc_frame *);
+
+/*
+ * command status codes
+ */
+#define FC_COMPLETE		0
+#define FC_CMD_ABORTED		1
+#define FC_CMD_RESET		2
+#define FC_CMD_PLOGO		3
+#define FC_SNS_RCV		4
+#define FC_TRANS_ERR		5
+#define FC_DATA_OVRRUN		6
+#define FC_DATA_UNDRUN		7
+#define FC_ERROR		8
+#define FC_HRD_ERROR		9
+#define FC_CMD_TIME_OUT		10
+
+/*
+ * Error recovery timeout values.
+ */
+#define FC_SCSI_ER_TIMEOUT	(10 * HZ)
+#define FC_SCSI_TM_TOV		(10 * HZ)
+#define FC_SCSI_REC_TOV		(2 * HZ)
+#define FC_HOST_RESET_TIMEOUT	(30 * HZ)
+
+#define FC_MAX_ERROR_CNT	5
+#define FC_MAX_RECOV_RETRY	3
+
+#define FC_FCP_DFLT_QUEUE_DEPTH 32
+
+/**
+ * fc_fcp_pkt_alloc - allocation routine for scsi_pkt packet
+ * @lp:		fc lport struct
+ * @gfp:	gfp flags for allocation
+ *
+ * This is used by upper layer scsi driver.
+ * Return Value : scsi_pkt structure or null on allocation failure.
+ * Context	: call from process context. no locking required.
+ */
+static struct fc_fcp_pkt *fc_fcp_pkt_alloc(struct fc_lport *lp, gfp_t gfp)
+{
+	struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
+	struct fc_fcp_pkt *fsp;
+
+	fsp = mempool_alloc(si->scsi_pkt_pool, gfp);
+	if (fsp) {
+		memset(fsp, 0, sizeof(*fsp));
+		fsp->lp = lp;
+		atomic_set(&fsp->ref_cnt, 1);
+		init_timer(&fsp->timer);
+		INIT_LIST_HEAD(&fsp->list);
+		spin_lock_init(&fsp->scsi_pkt_lock);
+	}
+	return fsp;
+}
+
+/**
+ * fc_fcp_pkt_release - release hold on scsi_pkt packet
+ * @fsp:	fcp packet struct
+ *
+ * This is used by upper layer scsi driver.
+ * Context	: call from process  and interrupt context.
+ *		  no locking required
+ */
+static void fc_fcp_pkt_release(struct fc_fcp_pkt *fsp)
+{
+	if (atomic_dec_and_test(&fsp->ref_cnt)) {
+		struct fc_fcp_internal *si = fc_get_scsi_internal(fsp->lp);
+
+		mempool_free(fsp, si->scsi_pkt_pool);
+	}
+}
+
+static void fc_fcp_pkt_hold(struct fc_fcp_pkt *fsp)
+{
+	atomic_inc(&fsp->ref_cnt);
+}
+
+/**
+ * fc_fcp_pkt_destory - release hold on scsi_pkt packet
+ *
+ * @seq:		exchange sequence
+ * @fsp:	fcp packet struct
+ *
+ * Release hold on scsi_pkt packet set to keep scsi_pkt
+ * till EM layer exch resource is not freed.
+ * Context	: called from from EM layer.
+ *		  no locking required
+ */
+static void fc_fcp_pkt_destroy(struct fc_seq *seq, void *fsp)
+{
+	fc_fcp_pkt_release(fsp);
+}
+
+/**
+ * fc_fcp_lock_pkt - lock a packet and get a ref to it.
+ * @fsp:	fcp packet
+ *
+ * We should only return error if we return a command to scsi-ml before
+ * getting a response. This can happen in cases where we send a abort, but
+ * do not wait for the response and the abort and command can be passing
+ * each other on the wire/network-layer.
+ *
+ * Note: this function locks the packet and gets a reference to allow
+ * callers to call the completion function while the lock is held and
+ * not have to worry about the packets refcount.
+ *
+ * TODO: Maybe we should just have callers grab/release the lock and
+ * have a function that they call to verify the fsp and grab a ref if
+ * needed.
+ */
+static inline int fc_fcp_lock_pkt(struct fc_fcp_pkt *fsp)
+{
+	spin_lock_bh(&fsp->scsi_pkt_lock);
+	if (fsp->state & FC_SRB_COMPL) {
+		spin_unlock_bh(&fsp->scsi_pkt_lock);
+		return -EPERM;
+	}
+
+	fc_fcp_pkt_hold(fsp);
+	return 0;
+}
+
+static inline void fc_fcp_unlock_pkt(struct fc_fcp_pkt *fsp)
+{
+	spin_unlock_bh(&fsp->scsi_pkt_lock);
+	fc_fcp_pkt_release(fsp);
+}
+
+static void fc_fcp_timer_set(struct fc_fcp_pkt *fsp, unsigned long delay)
+{
+	if (!(fsp->state & FC_SRB_COMPL))
+		mod_timer(&fsp->timer, jiffies + delay);
+}
+
+static int fc_fcp_send_abort(struct fc_fcp_pkt *fsp)
+{
+	if (!fsp->seq_ptr)
+		return -EINVAL;
+
+	fsp->state |= FC_SRB_ABORT_PENDING;
+	return fsp->lp->tt.seq_exch_abort(fsp->seq_ptr, 0);
+}
+
+/*
+ * Retry command.
+ * An abort isn't needed.
+ */
+static void fc_fcp_retry_cmd(struct fc_fcp_pkt *fsp)
+{
+	if (fsp->seq_ptr) {
+		fsp->lp->tt.exch_done(fsp->seq_ptr);
+		fsp->seq_ptr = NULL;
+	}
+
+	fsp->state &= ~FC_SRB_ABORT_PENDING;
+	fsp->io_status = SUGGEST_RETRY << 24;
+	fsp->status_code = FC_ERROR;
+	fc_fcp_complete_locked(fsp);
+}
+
+/*
+ * Receive SCSI data from target.
+ * Called after receiving solicited data.
+ */
+static void fc_fcp_recv_data(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
+{
+	struct scsi_cmnd *sc = fsp->cmd;
+	struct fc_lport *lp = fsp->lp;
+	struct fcoe_dev_stats *stats;
+	struct fc_frame_header *fh;
+	size_t start_offset;
+	size_t offset;
+	u32 crc;
+	u32 copy_len = 0;
+	size_t len;
+	void *buf;
+	struct scatterlist *sg;
+	size_t remaining;
+
+	fh = fc_frame_header_get(fp);
+	offset = ntohl(fh->fh_parm_offset);
+	start_offset = offset;
+	len = fr_len(fp) - sizeof(*fh);
+	buf = fc_frame_payload_get(fp, 0);
+
+	if (offset + len > fsp->data_len) {
+		/*
+		 * this should never happen
+		 */
+		if ((fr_flags(fp) & FCPHF_CRC_UNCHECKED) &&
+		    fc_frame_crc_check(fp))
+			goto crc_err;
+		FC_DEBUG_FCP("data received past end. len %zx offset %zx "
+			     "data_len %x\n", len, offset, fsp->data_len);
+		fc_fcp_retry_cmd(fsp);
+		return;
+	}
+	if (offset != fsp->xfer_len)
+		fsp->state |= FC_SRB_DISCONTIG;
+
+	crc = 0;
+	if (fr_flags(fp) & FCPHF_CRC_UNCHECKED)
+		crc = crc32(~0, (u8 *) fh, sizeof(*fh));
+
+	sg = scsi_sglist(sc);
+	remaining = len;
+
+	while (remaining > 0 && sg) {
+		size_t off;
+		void *page_addr;
+		size_t sg_bytes;
+
+		if (offset >= sg->length) {
+			offset -= sg->length;
+			sg = sg_next(sg);
+			continue;
+		}
+		sg_bytes = min(remaining, sg->length - offset);
+
+		/*
+		 * The scatterlist item may be bigger than PAGE_SIZE,
+		 * but we are limited to mapping PAGE_SIZE at a time.
+		 */
+		off = offset + sg->offset;
+		sg_bytes = min(sg_bytes, (size_t)
+			       (PAGE_SIZE - (off & ~PAGE_MASK)));
+		page_addr = kmap_atomic(sg_page(sg) + (off >> PAGE_SHIFT),
+					KM_SOFTIRQ0);
+		if (!page_addr)
+			break;		/* XXX panic? */
+
+		if (fr_flags(fp) & FCPHF_CRC_UNCHECKED)
+			crc = crc32(crc, buf, sg_bytes);
+		memcpy((char *)page_addr + (off & ~PAGE_MASK), buf,
+		       sg_bytes);
+
+		kunmap_atomic(page_addr, KM_SOFTIRQ0);
+		buf += sg_bytes;
+		offset += sg_bytes;
+		remaining -= sg_bytes;
+		copy_len += sg_bytes;
+	}
+
+	if (fr_flags(fp) & FCPHF_CRC_UNCHECKED) {
+		buf = fc_frame_payload_get(fp, 0);
+		if (len % 4) {
+			crc = crc32(crc, buf + len, 4 - (len % 4));
+			len += 4 - (len % 4);
+		}
+
+		if (~crc != le32_to_cpu(fr_crc(fp))) {
+crc_err:
+			stats = lp->dev_stats[smp_processor_id()];
+			stats->ErrorFrames++;
+			if (stats->InvalidCRCCount++ < 5)
+				FC_DBG("CRC error on data frame\n");
+			/*
+			 * Assume the frame is total garbage.
+			 * We may have copied it over the good part
+			 * of the buffer.
+			 * If so, we need to retry the entire operation.
+			 * Otherwise, ignore it.
+			 */
+			if (fsp->state & FC_SRB_DISCONTIG)
+				fc_fcp_retry_cmd(fsp);
+			return;
+		}
+	}
+
+	if (fsp->xfer_contig_end == start_offset)
+		fsp->xfer_contig_end += copy_len;
+	fsp->xfer_len += copy_len;
+
+	/*
+	 * In the very rare event that this data arrived after the response
+	 * and completes the transfer, call the completion handler.
+	 */
+	if (unlikely(fsp->state & FC_SRB_RCV_STATUS) &&
+	    fsp->xfer_len == fsp->data_len - fsp->scsi_resid)
+		fc_fcp_complete_locked(fsp);
+}
+
+/*
+ * fc_fcp_send_data -  Send SCSI data to target.
+ * @fsp: ptr to fc_fcp_pkt
+ * @sp: ptr to this sequence
+ * @offset: starting offset for this data request
+ * @seq_blen: the burst length for this data request
+ *
+ * Called after receiving a Transfer Ready data descriptor.
+ * if LLD is capable of seq offload then send down seq_blen
+ * size of data in single frame, otherwise send multiple FC
+ * frames of max FC frame payload supported by target port.
+ *
+ * Returns : 0 for success.
+ */
+static int fc_fcp_send_data(struct fc_fcp_pkt *fsp, struct fc_seq *seq,
+			    size_t offset, size_t seq_blen)
+{
+	struct fc_exch *ep;
+	struct scsi_cmnd *sc;
+	struct scatterlist *sg;
+	struct fc_frame *fp = NULL;
+	struct fc_lport *lp = fsp->lp;
+	size_t remaining;
+	size_t t_blen;
+	size_t tlen;
+	size_t sg_bytes;
+	size_t frame_offset, fh_parm_offset;
+	int error;
+	void *data = NULL;
+	void *page_addr;
+	int using_sg = lp->sg_supp;
+	u32 f_ctl;
+
+	WARN_ON(seq_blen <= 0);
+	if (unlikely(offset + seq_blen > fsp->data_len)) {
+		/* this should never happen */
+		FC_DEBUG_FCP("xfer-ready past end. seq_blen %zx offset %zx\n",
+			     seq_blen, offset);
+		fc_fcp_send_abort(fsp);
+		return 0;
+	} else if (offset != fsp->xfer_len) {
+		/* Out of Order Data Request - no problem, but unexpected. */
+		FC_DEBUG_FCP("xfer-ready non-contiguous. "
+			     "seq_blen %zx offset %zx\n", seq_blen, offset);
+	}
+
+	/*
+	 * if LLD is capable of seq_offload then set transport
+	 * burst length (t_blen) to seq_blen, otherwise set t_blen
+	 * to max FC frame payload previously set in fsp->max_payload.
+	 */
+	t_blen = lp->seq_offload ? seq_blen : fsp->max_payload;
+	WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD);
+	if (t_blen > 512)
+		t_blen &= ~(512 - 1);	/* round down to block size */
+	WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD);	/* won't go below 256 */
+	sc = fsp->cmd;
+
+	remaining = seq_blen;
+	fh_parm_offset = frame_offset = offset;
+	tlen = 0;
+	seq = lp->tt.seq_start_next(seq);
+	f_ctl = FC_FC_REL_OFF;
+	WARN_ON(!seq);
+
+	/*
+	 * If a get_page()/put_page() will fail, don't use sg lists
+	 * in the fc_frame structure.
+	 *
+	 * The put_page() may be long after the I/O has completed
+	 * in the case of FCoE, since the network driver does it
+	 * via free_skb().  See the test in free_pages_check().
+	 *
+	 * Test this case with 'dd </dev/zero >/dev/st0 bs=64k'.
+	 */
+	if (using_sg) {
+		for (sg = scsi_sglist(sc); sg; sg = sg_next(sg)) {
+			if (page_count(sg_page(sg)) == 0 ||
+			    (sg_page(sg)->flags & (1 << PG_lru |
+						   1 << PG_private |
+						   1 << PG_locked |
+						   1 << PG_active |
+						   1 << PG_slab |
+						   1 << PG_swapcache |
+						   1 << PG_writeback |
+						   1 << PG_reserved |
+						   1 << PG_buddy))) {
+				using_sg = 0;
+				break;
+			}
+		}
+	}
+	sg = scsi_sglist(sc);
+
+	while (remaining > 0 && sg) {
+		if (offset >= sg->length) {
+			offset -= sg->length;
+			sg = sg_next(sg);
+			continue;
+		}
+		if (!fp) {
+			tlen = min(t_blen, remaining);
+
+			/*
+			 * TODO.  Temporary workaround.	 fc_seq_send() can't
+			 * handle odd lengths in non-linear skbs.
+			 * This will be the final fragment only.
+			 */
+			if (tlen % 4)
+				using_sg = 0;
+			if (using_sg) {
+				fp = _fc_frame_alloc(lp, 0);
+				if (!fp)
+					return -ENOMEM;
+			} else {
+				fp = fc_frame_alloc(lp, tlen);
+				if (!fp)
+					return -ENOMEM;
+
+				data = (void *)(fr_hdr(fp)) +
+					sizeof(struct fc_frame_header);
+			}
+			fh_parm_offset = frame_offset;
+			fr_max_payload(fp) = fsp->max_payload;
+		}
+		sg_bytes = min(tlen, sg->length - offset);
+		if (using_sg) {
+			WARN_ON(skb_shinfo(fp_skb(fp))->nr_frags >
+				FC_FRAME_SG_LEN);
+			get_page(sg_page(sg));
+			skb_fill_page_desc(fp_skb(fp),
+					   skb_shinfo(fp_skb(fp))->nr_frags,
+					   sg_page(sg), sg->offset + offset,
+					   sg_bytes);
+			fp_skb(fp)->data_len += sg_bytes;
+			fr_len(fp) += sg_bytes;
+			fp_skb(fp)->truesize += PAGE_SIZE;
+		} else {
+			size_t off = offset + sg->offset;
+
+			/*
+			 * The scatterlist item may be bigger than PAGE_SIZE,
+			 * but we must not cross pages inside the kmap.
+			 */
+			sg_bytes = min(sg_bytes, (size_t) (PAGE_SIZE -
+							   (off & ~PAGE_MASK)));
+			page_addr = kmap_atomic(sg_page(sg) +
+						(off >> PAGE_SHIFT),
+						KM_SOFTIRQ0);
+			memcpy(data, (char *)page_addr + (off & ~PAGE_MASK),
+			       sg_bytes);
+			kunmap_atomic(page_addr, KM_SOFTIRQ0);
+			data += sg_bytes;
+		}
+		offset += sg_bytes;
+		frame_offset += sg_bytes;
+		tlen -= sg_bytes;
+		remaining -= sg_bytes;
+
+		if (tlen)
+			continue;
+
+		/*
+		 * Send sequence with transfer sequence initiative in case
+		 * this is last FCP frame of the sequence.
+		 */
+		if (remaining == 0)
+			f_ctl |= FC_FC_SEQ_INIT | FC_FC_END_SEQ;
+
+		ep = fc_seq_exch(seq);
+		fc_fill_fc_hdr(fp, FC_RCTL_DD_SOL_DATA, ep->did, ep->sid,
+			       FC_TYPE_FCP, f_ctl, fh_parm_offset);
+
+		/*
+		 * send fragment using for a sequence.
+		 */
+		error = lp->tt.seq_send(lp, seq, fp);
+		if (error) {
+			WARN_ON(1);		/* send error should be rare */
+			fc_fcp_retry_cmd(fsp);
+			return 0;
+		}
+		fp = NULL;
+	}
+	fsp->xfer_len += seq_blen;	/* premature count? */
+	return 0;
+}
+
+static void fc_fcp_abts_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
+{
+	int ba_done = 1;
+	struct fc_ba_rjt *brp;
+	struct fc_frame_header *fh;
+
+	fh = fc_frame_header_get(fp);
+	switch (fh->fh_r_ctl) {
+	case FC_RCTL_BA_ACC:
+		break;
+	case FC_RCTL_BA_RJT:
+		brp = fc_frame_payload_get(fp, sizeof(*brp));
+		if (brp && brp->br_reason == FC_BA_RJT_LOG_ERR)
+			break;
+		/* fall thru */
+	default:
+		/*
+		 * we will let the command timeout
+		 * and scsi-ml recover in this case,
+		 * therefore cleared the ba_done flag.
+		 */
+		ba_done = 0;
+	}
+
+	if (ba_done) {
+		fsp->state |= FC_SRB_ABORTED;
+		fsp->state &= ~FC_SRB_ABORT_PENDING;
+
+		if (fsp->wait_for_comp)
+			complete(&fsp->tm_done);
+		else
+			fc_fcp_complete_locked(fsp);
+	}
+}
+
+/*
+ * fc_fcp_reduce_can_queue - drop can_queue
+ * @lp: lport to drop queueing for
+ *
+ * If we are getting memory allocation failures, then we may
+ * be trying to execute too many commands. We let the running
+ * commands complete or timeout, then try again with a reduced
+ * can_queue. Eventually we will hit the point where we run
+ * on all reserved structs.
+ */
+static void fc_fcp_reduce_can_queue(struct fc_lport *lp)
+{
+	struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
+	unsigned long flags;
+	int can_queue;
+
+	spin_lock_irqsave(lp->host->host_lock, flags);
+	if (si->throttled)
+		goto done;
+	si->throttled = 1;
+
+	can_queue = lp->host->can_queue;
+	can_queue >>= 1;
+	if (!can_queue)
+		can_queue = 1;
+	lp->host->can_queue = can_queue;
+	shost_printk(KERN_ERR, lp->host, "Could not allocate frame.\n"
+		     "Reducing can_queue to %d.\n", can_queue);
+done:
+	spin_unlock_irqrestore(lp->host->host_lock, flags);
+}
+
+/*
+ * exch mgr calls this routine to process scsi
+ * exchanges.
+ *
+ * Return   : None
+ * Context  : called from Soft IRQ context
+ *	      can not called holding list lock
+ */
+static void fc_fcp_recv(struct fc_seq *seq, struct fc_frame *fp, void *arg)
+{
+	struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
+	struct fc_lport *lp;
+	struct fc_frame_header *fh;
+	struct fcp_txrdy *dd;
+	u8 r_ctl;
+	int rc = 0;
+
+	if (IS_ERR(fp))
+		goto errout;
+
+	fh = fc_frame_header_get(fp);
+	r_ctl = fh->fh_r_ctl;
+	lp = fsp->lp;
+
+	if (!(lp->state & LPORT_ST_READY))
+		goto out;
+	if (fc_fcp_lock_pkt(fsp))
+		goto out;
+	fsp->last_pkt_time = jiffies;
+
+	if (fh->fh_type == FC_TYPE_BLS) {
+		fc_fcp_abts_resp(fsp, fp);
+		goto unlock;
+	}
+
+	if (fsp->state & (FC_SRB_ABORTED | FC_SRB_ABORT_PENDING))
+		goto unlock;
+
+	if (r_ctl == FC_RCTL_DD_DATA_DESC) {
+		/*
+		 * received XFER RDY from the target
+		 * need to send data to the target
+		 */
+		WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
+		dd = fc_frame_payload_get(fp, sizeof(*dd));
+		WARN_ON(!dd);
+
+		rc = fc_fcp_send_data(fsp, seq,
+				      (size_t) ntohl(dd->ft_data_ro),
+				      (size_t) ntohl(dd->ft_burst_len));
+		if (!rc)
+			seq->rec_data = fsp->xfer_len;
+		else if (rc == -ENOMEM)
+			fsp->state |= FC_SRB_NOMEM;
+	} else if (r_ctl == FC_RCTL_DD_SOL_DATA) {
+		/*
+		 * received a DATA frame
+		 * next we will copy the data to the system buffer
+		 */
+		WARN_ON(fr_len(fp) < sizeof(*fh));	/* len may be 0 */
+		fc_fcp_recv_data(fsp, fp);
+		seq->rec_data = fsp->xfer_contig_end;
+	} else if (r_ctl == FC_RCTL_DD_CMD_STATUS) {
+		WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
+
+		fc_fcp_resp(fsp, fp);
+	} else {
+		FC_DBG("unexpected frame.  r_ctl %x\n", r_ctl);
+	}
+unlock:
+	fc_fcp_unlock_pkt(fsp);
+out:
+	fc_frame_free(fp);
+errout:
+	if (IS_ERR(fp))
+		fc_fcp_error(fsp, fp);
+	else if (rc == -ENOMEM)
+		fc_fcp_reduce_can_queue(lp);
+}
+
+static void fc_fcp_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
+{
+	struct fc_frame_header *fh;
+	struct fcp_resp *fc_rp;
+	struct fcp_resp_ext *rp_ex;
+	struct fcp_resp_rsp_info *fc_rp_info;
+	u32 plen;
+	u32 expected_len;
+	u32 respl = 0;
+	u32 snsl = 0;
+	u8 flags = 0;
+
+	plen = fr_len(fp);
+	fh = (struct fc_frame_header *)fr_hdr(fp);
+	if (unlikely(plen < sizeof(*fh) + sizeof(*fc_rp)))
+		goto len_err;
+	plen -= sizeof(*fh);
+	fc_rp = (struct fcp_resp *)(fh + 1);
+	fsp->cdb_status = fc_rp->fr_status;
+	flags = fc_rp->fr_flags;
+	fsp->scsi_comp_flags = flags;
+	expected_len = fsp->data_len;
+
+	if (unlikely((flags & ~FCP_CONF_REQ) || fc_rp->fr_status)) {
+		rp_ex = (void *)(fc_rp + 1);
+		if (flags & (FCP_RSP_LEN_VAL | FCP_SNS_LEN_VAL)) {
+			if (plen < sizeof(*fc_rp) + sizeof(*rp_ex))
+				goto len_err;
+			fc_rp_info = (struct fcp_resp_rsp_info *)(rp_ex + 1);
+			if (flags & FCP_RSP_LEN_VAL) {
+				respl = ntohl(rp_ex->fr_rsp_len);
+				if (respl != sizeof(*fc_rp_info))
+					goto len_err;
+				if (fsp->wait_for_comp) {
+					/* Abuse cdb_status for rsp code */
+					fsp->cdb_status = fc_rp_info->rsp_code;
+					complete(&fsp->tm_done);
+					/*
+					 * tmfs will not have any scsi cmd so
+					 * exit here
+					 */
+					return;
+				} else
+					goto err;
+			}
+			if (flags & FCP_SNS_LEN_VAL) {
+				snsl = ntohl(rp_ex->fr_sns_len);
+				if (snsl > SCSI_SENSE_BUFFERSIZE)
+					snsl = SCSI_SENSE_BUFFERSIZE;
+				memcpy(fsp->cmd->sense_buffer,
+				       (char *)fc_rp_info + respl, snsl);
+			}
+		}
+		if (flags & (FCP_RESID_UNDER | FCP_RESID_OVER)) {
+			if (plen < sizeof(*fc_rp) + sizeof(rp_ex->fr_resid))
+				goto len_err;
+			if (flags & FCP_RESID_UNDER) {
+				fsp->scsi_resid = ntohl(rp_ex->fr_resid);
+				/*
+				 * The cmnd->underflow is the minimum number of
+				 * bytes that must be transfered for this
+				 * command.  Provided a sense condition is not
+				 * present, make sure the actual amount
+				 * transferred is at least the underflow value
+				 * or fail.
+				 */
+				if (!(flags & FCP_SNS_LEN_VAL) &&
+				    (fc_rp->fr_status == 0) &&
+				    (scsi_bufflen(fsp->cmd) -
+				     fsp->scsi_resid) < fsp->cmd->underflow)
+					goto err;
+				expected_len -= fsp->scsi_resid;
+			} else {
+				fsp->status_code = FC_ERROR;
+			}
+		}
+	}
+	fsp->state |= FC_SRB_RCV_STATUS;
+
+	/*
+	 * Check for missing or extra data frames.
+	 */
+	if (unlikely(fsp->xfer_len != expected_len)) {
+		if (fsp->xfer_len < expected_len) {
+			/*
+			 * Some data may be queued locally,
+			 * Wait a at least one jiffy to see if it is delivered.
+			 * If this expires without data, we may do SRR.
+			 */
+			fc_fcp_timer_set(fsp, 2);
+			return;
+		}
+		fsp->status_code = FC_DATA_OVRRUN;
+		FC_DBG("tgt %6x xfer len %zx greater than expected len %x. "
+		       "data len %x\n",
+		       fsp->rport->port_id,
+		       fsp->xfer_len, expected_len, fsp->data_len);
+	}
+	fc_fcp_complete_locked(fsp);
+	return;
+
+len_err:
+	FC_DBG("short FCP response. flags 0x%x len %u respl %u snsl %u\n",
+	       flags, fr_len(fp), respl, snsl);
+err:
+	fsp->status_code = FC_ERROR;
+	fc_fcp_complete_locked(fsp);
+}
+
+/**
+ * fc_fcp_complete_locked - complete processing of a fcp packet
+ * @fsp:	fcp packet
+ *
+ * This function may sleep if a timer is pending. The packet lock must be
+ * held, and the host lock must not be held.
+ */
+static void fc_fcp_complete_locked(struct fc_fcp_pkt *fsp)
+{
+	struct fc_lport *lp = fsp->lp;
+	struct fc_seq *seq;
+	struct fc_exch *ep;
+	u32 f_ctl;
+
+	if (fsp->state & FC_SRB_ABORT_PENDING)
+		return;
+
+	if (fsp->state & FC_SRB_ABORTED) {
+		if (!fsp->status_code)
+			fsp->status_code = FC_CMD_ABORTED;
+	} else {
+		/*
+		 * Test for transport underrun, independent of response
+		 * underrun status.
+		 */
+		if (fsp->xfer_len < fsp->data_len && !fsp->io_status &&
+		    (!(fsp->scsi_comp_flags & FCP_RESID_UNDER) ||
+		     fsp->xfer_len < fsp->data_len - fsp->scsi_resid)) {
+			fsp->status_code = FC_DATA_UNDRUN;
+			fsp->io_status = SUGGEST_RETRY << 24;
+		}
+	}
+
+	seq = fsp->seq_ptr;
+	if (seq) {
+		fsp->seq_ptr = NULL;
+		if (unlikely(fsp->scsi_comp_flags & FCP_CONF_REQ)) {
+			struct fc_frame *conf_frame;
+			struct fc_seq *csp;
+
+			csp = lp->tt.seq_start_next(seq);
+			conf_frame = fc_frame_alloc(fsp->lp, 0);
+			if (conf_frame) {
+				f_ctl = FC_FC_SEQ_INIT;
+				f_ctl |= FC_FC_LAST_SEQ | FC_FC_END_SEQ;
+				ep = fc_seq_exch(seq);
+				fc_fill_fc_hdr(conf_frame, FC_RCTL_DD_SOL_CTL,
+					       ep->did, ep->sid,
+					       FC_TYPE_FCP, f_ctl, 0);
+				lp->tt.seq_send(lp, csp, conf_frame);
+			}
+		}
+		lp->tt.exch_done(seq);
+	}
+	fc_io_compl(fsp);
+}
+
+static void fc_fcp_cleanup_cmd(struct fc_fcp_pkt *fsp, int error)
+{
+	struct fc_lport *lp = fsp->lp;
+
+	if (fsp->seq_ptr) {
+		lp->tt.exch_done(fsp->seq_ptr);
+		fsp->seq_ptr = NULL;
+	}
+	fsp->status_code = error;
+}
+
+/**
+ * fc_fcp_cleanup_each_cmd - run fn on each active command
+ * @lp:		logical port
+ * @id:		target id
+ * @lun:	lun
+ * @error:	fsp status code
+ *
+ * If lun or id is -1, they are ignored.
+ */
+static void fc_fcp_cleanup_each_cmd(struct fc_lport *lp, unsigned int id,
+				    unsigned int lun, int error)
+{
+	struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
+	struct fc_fcp_pkt *fsp;
+	struct scsi_cmnd *sc_cmd;
+	unsigned long flags;
+
+	spin_lock_irqsave(lp->host->host_lock, flags);
+restart:
+	list_for_each_entry(fsp, &si->scsi_pkt_queue, list) {
+		sc_cmd = fsp->cmd;
+		if (id != -1 && scmd_id(sc_cmd) != id)
+			continue;
+
+		if (lun != -1 && sc_cmd->device->lun != lun)
+			continue;
+
+		fc_fcp_pkt_hold(fsp);
+		spin_unlock_irqrestore(lp->host->host_lock, flags);
+
+		if (!fc_fcp_lock_pkt(fsp)) {
+			fc_fcp_cleanup_cmd(fsp, error);
+			fc_io_compl(fsp);
+			fc_fcp_unlock_pkt(fsp);
+		}
+
+		fc_fcp_pkt_release(fsp);
+		spin_lock_irqsave(lp->host->host_lock, flags);
+		/*
+		 * while we dropped the lock multiple pkts could
+		 * have been released, so we have to start over.
+		 */
+		goto restart;
+	}
+	spin_unlock_irqrestore(lp->host->host_lock, flags);
+}
+
+static void fc_fcp_abort_io(struct fc_lport *lp)
+{
+	fc_fcp_cleanup_each_cmd(lp, -1, -1, FC_HRD_ERROR);
+}
+
+/**
+ * fc_fcp_pkt_send - send a fcp packet to the lower level.
+ * @lp:		fc lport
+ * @fsp:	fc packet.
+ *
+ * This is called by upper layer protocol.
+ * Return   : zero for success and -1 for failure
+ * Context  : called from queuecommand which can be called from process
+ *	      or scsi soft irq.
+ * Locks    : called with the host lock and irqs disabled.
+ */
+static int fc_fcp_pkt_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp)
+{
+	struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
+	int rc;
+
+	fsp->cmd->SCp.ptr = (char *)fsp;
+	fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
+	fsp->cdb_cmd.fc_flags = fsp->req_flags & ~FCP_CFL_LEN_MASK;
+
+	int_to_scsilun(fsp->cmd->device->lun,
+		       (struct scsi_lun *)fsp->cdb_cmd.fc_lun);
+	memcpy(fsp->cdb_cmd.fc_cdb, fsp->cmd->cmnd, fsp->cmd->cmd_len);
+	list_add_tail(&fsp->list, &si->scsi_pkt_queue);
+
+	spin_unlock_irq(lp->host->host_lock);
+	rc = lp->tt.fcp_cmd_send(lp, fsp, fc_fcp_recv);
+	spin_lock_irq(lp->host->host_lock);
+	if (rc)
+		list_del(&fsp->list);
+
+	return rc;
+}
+
+static int fc_fcp_cmd_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
+			   void (*resp)(struct fc_seq *,
+					struct fc_frame *fp,
+					void *arg))
+{
+	struct fc_frame *fp;
+	struct fc_seq *seq;
+	struct fc_rport *rport;
+	struct fc_rport_libfc_priv *rp;
+	const size_t len = sizeof(fsp->cdb_cmd);
+	int rc = 0;
+
+	if (fc_fcp_lock_pkt(fsp))
+		return 0;
+
+	fp = fc_frame_alloc(lp, sizeof(fsp->cdb_cmd));
+	if (!fp) {
+		rc = -1;
+		goto unlock;
+	}
+
+	memcpy(fc_frame_payload_get(fp, len), &fsp->cdb_cmd, len);
+	fr_cmd(fp) = fsp->cmd;
+	rport = fsp->rport;
+	fsp->max_payload = rport->maxframe_size;
+	rp = rport->dd_data;
+
+	fc_fill_fc_hdr(fp, FC_RCTL_DD_UNSOL_CMD, rport->port_id,
+		       fc_host_port_id(rp->local_port->host), FC_TYPE_FCP,
+		       FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
+
+	seq = lp->tt.exch_seq_send(lp, fp, resp, fc_fcp_pkt_destroy, fsp, 0);
+	if (!seq) {
+		fc_frame_free(fp);
+		rc = -1;
+		goto unlock;
+	}
+	fsp->last_pkt_time = jiffies;
+	fsp->seq_ptr = seq;
+	fc_fcp_pkt_hold(fsp);	/* hold for fc_fcp_pkt_destroy */
+
+	setup_timer(&fsp->timer, fc_fcp_timeout, (unsigned long)fsp);
+	fc_fcp_timer_set(fsp,
+			 (fsp->tgt_flags & FC_RP_FLAGS_REC_SUPPORTED) ?
+			 FC_SCSI_REC_TOV : FC_SCSI_ER_TIMEOUT);
+unlock:
+	fc_fcp_unlock_pkt(fsp);
+	return rc;
+}
+
+/*
+ * transport error handler
+ */
+static void fc_fcp_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
+{
+	int error = PTR_ERR(fp);
+
+	if (fc_fcp_lock_pkt(fsp))
+		return;
+
+	switch (error) {
+	case -FC_EX_CLOSED:
+		fc_fcp_retry_cmd(fsp);
+		goto unlock;
+	default:
+		FC_DBG("unknown error %ld\n", PTR_ERR(fp));
+	}
+	/*
+	 * clear abort pending, because the lower layer
+	 * decided to force completion.
+	 */
+	fsp->state &= ~FC_SRB_ABORT_PENDING;
+	fsp->status_code = FC_CMD_PLOGO;
+	fc_fcp_complete_locked(fsp);
+unlock:
+	fc_fcp_unlock_pkt(fsp);
+}
+
+/*
+ * Scsi abort handler- calls to send an abort
+ * and then wait for abort completion
+ */
+static int fc_fcp_pkt_abort(struct fc_lport *lp, struct fc_fcp_pkt *fsp)
+{
+	int rc = FAILED;
+
+	if (fc_fcp_send_abort(fsp))
+		return FAILED;
+
+	init_completion(&fsp->tm_done);
+	fsp->wait_for_comp = 1;
+
+	spin_unlock_bh(&fsp->scsi_pkt_lock);
+	rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);
+	spin_lock_bh(&fsp->scsi_pkt_lock);
+	fsp->wait_for_comp = 0;
+
+	if (!rc) {
+		FC_DBG("target abort cmd  failed\n");
+		rc = FAILED;
+	} else if (fsp->state & FC_SRB_ABORTED) {
+		FC_DBG("target abort cmd  passed\n");
+		rc = SUCCESS;
+		fc_fcp_complete_locked(fsp);
+	}
+
+	return rc;
+}
+
+/*
+ * Retry LUN reset after resource allocation failed.
+ */
+static void fc_lun_reset_send(unsigned long data)
+{
+	struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
+	struct fc_lport *lp = fsp->lp;
+	if (lp->tt.fcp_cmd_send(lp, fsp, fc_tm_done)) {
+		if (fsp->recov_retry++ >= FC_MAX_RECOV_RETRY)
+			return;
+		if (fc_fcp_lock_pkt(fsp))
+			return;
+		setup_timer(&fsp->timer, fc_lun_reset_send, (unsigned long)fsp);
+		fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
+		fc_fcp_unlock_pkt(fsp);
+	}
+}
+
+/*
+ * Scsi device reset handler- send a LUN RESET to the device
+ * and wait for reset reply
+ */
+static int fc_lun_reset(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
+			unsigned int id, unsigned int lun)
+{
+	int rc;
+
+	fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
+	fsp->cdb_cmd.fc_tm_flags = FCP_TMF_LUN_RESET;
+	int_to_scsilun(lun, (struct scsi_lun *)fsp->cdb_cmd.fc_lun);
+
+	fsp->wait_for_comp = 1;
+	init_completion(&fsp->tm_done);
+
+	fc_lun_reset_send((unsigned long)fsp);
+
+	/*
+	 * wait for completion of reset
+	 * after that make sure all commands are terminated
+	 */
+	rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);
+
+	spin_lock_bh(&fsp->scsi_pkt_lock);
+	fsp->state |= FC_SRB_COMPL;
+	spin_unlock_bh(&fsp->scsi_pkt_lock);
+
+	del_timer_sync(&fsp->timer);
+
+	spin_lock_bh(&fsp->scsi_pkt_lock);
+	if (fsp->seq_ptr) {
+		lp->tt.exch_done(fsp->seq_ptr);
+		fsp->seq_ptr = NULL;
+	}
+	fsp->wait_for_comp = 0;
+	spin_unlock_bh(&fsp->scsi_pkt_lock);
+
+	if (!rc) {
+		FC_DBG("lun reset failed\n");
+		return FAILED;
+	}
+
+	/* cdb_status holds the tmf's rsp code */
+	if (fsp->cdb_status != FCP_TMF_CMPL)
+		return FAILED;
+
+	FC_DBG("lun reset to lun %u completed\n", lun);
+	fc_fcp_cleanup_each_cmd(lp, id, lun, FC_CMD_ABORTED);
+	return SUCCESS;
+}
+
+/*
+ * Task Managment response handler
+ */
+static void fc_tm_done(struct fc_seq *seq, struct fc_frame *fp, void *arg)
+{
+	struct fc_fcp_pkt *fsp = arg;
+	struct fc_frame_header *fh;
+
+	if (IS_ERR(fp)) {
+		/*
+		 * If there is an error just let it timeout or wait
+		 * for TMF to be aborted if it timedout.
+		 *
+		 * scsi-eh will escalate for when either happens.
+		 */
+		return;
+	}
+
+	if (fc_fcp_lock_pkt(fsp))
+		return;
+
+	/*
+	 * raced with eh timeout handler.
+	 */
+	if (!fsp->seq_ptr || !fsp->wait_for_comp) {
+		spin_unlock_bh(&fsp->scsi_pkt_lock);
+		return;
+	}
+
+	fh = fc_frame_header_get(fp);
+	if (fh->fh_type != FC_TYPE_BLS)
+		fc_fcp_resp(fsp, fp);
+	fsp->seq_ptr = NULL;
+	fsp->lp->tt.exch_done(seq);
+	fc_frame_free(fp);
+	fc_fcp_unlock_pkt(fsp);
+}
+
+static void fc_fcp_cleanup(struct fc_lport *lp)
+{
+	fc_fcp_cleanup_each_cmd(lp, -1, -1, FC_ERROR);
+}
+
+/*
+ * fc_fcp_timeout: called by OS timer function.
+ *
+ * The timer has been inactivated and must be reactivated if desired
+ * using fc_fcp_timer_set().
+ *
+ * Algorithm:
+ *
+ * If REC is supported, just issue it, and return.  The REC exchange will
+ * complete or time out, and recovery can continue at that point.
+ *
+ * Otherwise, if the response has been received without all the data,
+ * it has been ER_TIMEOUT since the response was received.
+ *
+ * If the response has not been received,
+ * we see if data was received recently.  If it has been, we continue waiting,
+ * otherwise, we abort the command.
+ */
+static void fc_fcp_timeout(unsigned long data)
+{
+	struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
+	struct fc_rport *rport = fsp->rport;
+	struct fc_rport_libfc_priv *rp = rport->dd_data;
+
+	if (fc_fcp_lock_pkt(fsp))
+		return;
+
+	if (fsp->cdb_cmd.fc_tm_flags)
+		goto unlock;
+
+	fsp->state |= FC_SRB_FCP_PROCESSING_TMO;
+
+	if (rp->flags & FC_RP_FLAGS_REC_SUPPORTED)
+		fc_fcp_rec(fsp);
+	else if (time_after_eq(fsp->last_pkt_time + (FC_SCSI_ER_TIMEOUT / 2),
+			       jiffies))
+		fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
+	else if (fsp->state & FC_SRB_RCV_STATUS)
+		fc_fcp_complete_locked(fsp);
+	else
+		fc_timeout_error(fsp);
+	fsp->state &= ~FC_SRB_FCP_PROCESSING_TMO;
+unlock:
+	fc_fcp_unlock_pkt(fsp);
+}
+
+/*
+ * Send a REC ELS request
+ */
+static void fc_fcp_rec(struct fc_fcp_pkt *fsp)
+{
+	struct fc_lport *lp;
+	struct fc_frame *fp;
+	struct fc_rport *rport;
+	struct fc_rport_libfc_priv *rp;
+
+	lp = fsp->lp;
+	rport = fsp->rport;
+	rp = rport->dd_data;
+	if (!fsp->seq_ptr || rp->rp_state != RPORT_ST_READY) {
+		fsp->status_code = FC_HRD_ERROR;
+		fsp->io_status = SUGGEST_RETRY << 24;
+		fc_fcp_complete_locked(fsp);
+		return;
+	}
+	fp = fc_frame_alloc(lp, sizeof(struct fc_els_rec));
+	if (!fp)
+		goto retry;
+
+	fr_seq(fp) = fsp->seq_ptr;
+	fc_fill_fc_hdr(fp, FC_RCTL_ELS_REQ, rport->port_id,
+		       fc_host_port_id(rp->local_port->host), FC_TYPE_ELS,
+		       FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
+	if (lp->tt.elsct_send(lp, rport, fp, ELS_REC, fc_fcp_rec_resp,
+			      fsp, jiffies_to_msecs(FC_SCSI_REC_TOV))) {
+		fc_fcp_pkt_hold(fsp);		/* hold while REC outstanding */
+		return;
+	}
+	fc_frame_free(fp);
+retry:
+	if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
+		fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
+	else
+		fc_timeout_error(fsp);
+}
+
+/*
+ * Receive handler for REC ELS frame
+ * if it is a reject then let the scsi layer to handle
+ * the timeout. if it is a LS_ACC then if the io was not completed
+ * then set the timeout and return otherwise complete the exchange
+ * and tell the scsi layer to restart the I/O.
+ */
+static void fc_fcp_rec_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
+{
+	struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
+	struct fc_els_rec_acc *recp;
+	struct fc_els_ls_rjt *rjt;
+	u32 e_stat;
+	u8 opcode;
+	u32 offset;
+	enum dma_data_direction data_dir;
+	enum fc_rctl r_ctl;
+	struct fc_rport_libfc_priv *rp;
+
+	if (IS_ERR(fp)) {
+		fc_fcp_rec_error(fsp, fp);
+		return;
+	}
+
+	if (fc_fcp_lock_pkt(fsp))
+		goto out;
+
+	fsp->recov_retry = 0;
+	opcode = fc_frame_payload_op(fp);
+	if (opcode == ELS_LS_RJT) {
+		rjt = fc_frame_payload_get(fp, sizeof(*rjt));
+		switch (rjt->er_reason) {
+		default:
+			FC_DEBUG_FCP("device %x unexpected REC reject "
+				     "reason %d expl %d\n",
+				     fsp->rport->port_id, rjt->er_reason,
+				     rjt->er_explan);
+			/* fall through */
+		case ELS_RJT_UNSUP:
+			FC_DEBUG_FCP("device does not support REC\n");
+			rp = fsp->rport->dd_data;
+			/*
+			 * if we do not spport RECs or got some bogus
+			 * reason then resetup timer so we check for
+			 * making progress.
+			 */
+			rp->flags &= ~FC_RP_FLAGS_REC_SUPPORTED;
+			fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
+			break;
+		case ELS_RJT_LOGIC:
+		case ELS_RJT_UNAB:
+			/*
+			 * If no data transfer, the command frame got dropped
+			 * so we just retry.  If data was transferred, we
+			 * lost the response but the target has no record,
+			 * so we abort and retry.
+			 */
+			if (rjt->er_explan == ELS_EXPL_OXID_RXID &&
+			    fsp->xfer_len == 0) {
+				fc_fcp_retry_cmd(fsp);
+				break;
+			}
+			fc_timeout_error(fsp);
+			break;
+		}
+	} else if (opcode == ELS_LS_ACC) {
+		if (fsp->state & FC_SRB_ABORTED)
+			goto unlock_out;
+
+		data_dir = fsp->cmd->sc_data_direction;
+		recp = fc_frame_payload_get(fp, sizeof(*recp));
+		offset = ntohl(recp->reca_fc4value);
+		e_stat = ntohl(recp->reca_e_stat);
+
+		if (e_stat & ESB_ST_COMPLETE) {
+
+			/*
+			 * The exchange is complete.
+			 *
+			 * For output, we must've lost the response.
+			 * For input, all data must've been sent.
+			 * We lost may have lost the response
+			 * (and a confirmation was requested) and maybe
+			 * some data.
+			 *
+			 * If all data received, send SRR
+			 * asking for response.	 If partial data received,
+			 * or gaps, SRR requests data at start of gap.
+			 * Recovery via SRR relies on in-order-delivery.
+			 */
+			if (data_dir == DMA_TO_DEVICE) {
+				r_ctl = FC_RCTL_DD_CMD_STATUS;
+			} else if (fsp->xfer_contig_end == offset) {
+				r_ctl = FC_RCTL_DD_CMD_STATUS;
+			} else {
+				offset = fsp->xfer_contig_end;
+				r_ctl = FC_RCTL_DD_SOL_DATA;
+			}
+			fc_fcp_srr(fsp, r_ctl, offset);
+		} else if (e_stat & ESB_ST_SEQ_INIT) {
+
+			/*
+			 * The remote port has the initiative, so just
+			 * keep waiting for it to complete.
+			 */
+			fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
+		} else {
+
+			/*
+			 * The exchange is incomplete, we have seq. initiative.
+			 * Lost response with requested confirmation,
+			 * lost confirmation, lost transfer ready or
+			 * lost write data.
+			 *
+			 * For output, if not all data was received, ask
+			 * for transfer ready to be repeated.
+			 *
+			 * If we received or sent all the data, send SRR to
+			 * request response.
+			 *
+			 * If we lost a response, we may have lost some read
+			 * data as well.
+			 */
+			r_ctl = FC_RCTL_DD_SOL_DATA;
+			if (data_dir == DMA_TO_DEVICE) {
+				r_ctl = FC_RCTL_DD_CMD_STATUS;
+				if (offset < fsp->data_len)
+					r_ctl = FC_RCTL_DD_DATA_DESC;
+			} else if (offset == fsp->xfer_contig_end) {
+				r_ctl = FC_RCTL_DD_CMD_STATUS;
+			} else if (fsp->xfer_contig_end < offset) {
+				offset = fsp->xfer_contig_end;
+			}
+			fc_fcp_srr(fsp, r_ctl, offset);
+		}
+	}
+unlock_out:
+	fc_fcp_unlock_pkt(fsp);
+out:
+	fc_fcp_pkt_release(fsp);	/* drop hold for outstanding REC */
+	fc_frame_free(fp);
+}
+
+/*
+ * Handle error response or timeout for REC exchange.
+ */
+static void fc_fcp_rec_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
+{
+	int error = PTR_ERR(fp);
+
+	if (fc_fcp_lock_pkt(fsp))
+		goto out;
+
+	switch (error) {
+	case -FC_EX_CLOSED:
+		fc_fcp_retry_cmd(fsp);
+		break;
+
+	default:
+		FC_DBG("REC %p fid %x error unexpected error %d\n",
+		       fsp, fsp->rport->port_id, error);
+		fsp->status_code = FC_CMD_PLOGO;
+		/* fall through */
+
+	case -FC_EX_TIMEOUT:
+		/*
+		 * Assume REC or LS_ACC was lost.
+		 * The exchange manager will have aborted REC, so retry.
+		 */
+		FC_DBG("REC fid %x error error %d retry %d/%d\n",
+		       fsp->rport->port_id, error, fsp->recov_retry,
+		       FC_MAX_RECOV_RETRY);
+		if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
+			fc_fcp_rec(fsp);
+		else
+			fc_timeout_error(fsp);
+		break;
+	}
+	fc_fcp_unlock_pkt(fsp);
+out:
+	fc_fcp_pkt_release(fsp);	/* drop hold for outstanding REC */
+}
+
+/*
+ * Time out error routine:
+ * abort's the I/O close the exchange and
+ * send completion notification to scsi layer
+ */
+static void fc_timeout_error(struct fc_fcp_pkt *fsp)
+{
+	fsp->status_code = FC_CMD_TIME_OUT;
+	fsp->cdb_status = 0;
+	fsp->io_status = 0;
+	/*
+	 * if this fails then we let the scsi command timer fire and
+	 * scsi-ml escalate.
+	 */
+	fc_fcp_send_abort(fsp);
+}
+
+/*
+ * Sequence retransmission request.
+ * This is called after receiving status but insufficient data, or
+ * when expecting status but the request has timed out.
+ */
+static void fc_fcp_srr(struct fc_fcp_pkt *fsp, enum fc_rctl r_ctl, u32 offset)
+{
+	struct fc_lport *lp = fsp->lp;
+	struct fc_rport *rport;
+	struct fc_rport_libfc_priv *rp;
+	struct fc_exch *ep = fc_seq_exch(fsp->seq_ptr);
+	struct fc_seq *seq;
+	struct fcp_srr *srr;
+	struct fc_frame *fp;
+	u8 cdb_op;
+
+	rport = fsp->rport;
+	rp = rport->dd_data;
+	cdb_op = fsp->cdb_cmd.fc_cdb[0];
+
+	if (!(rp->flags & FC_RP_FLAGS_RETRY) || rp->rp_state != RPORT_ST_READY)
+		goto retry;			/* shouldn't happen */
+	fp = fc_frame_alloc(lp, sizeof(*srr));
+	if (!fp)
+		goto retry;
+
+	srr = fc_frame_payload_get(fp, sizeof(*srr));
+	memset(srr, 0, sizeof(*srr));
+	srr->srr_op = ELS_SRR;
+	srr->srr_ox_id = htons(ep->oxid);
+	srr->srr_rx_id = htons(ep->rxid);
+	srr->srr_r_ctl = r_ctl;
+	srr->srr_rel_off = htonl(offset);
+
+	fc_fill_fc_hdr(fp, FC_RCTL_ELS4_REQ, rport->port_id,
+		       fc_host_port_id(rp->local_port->host), FC_TYPE_FCP,
+		       FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
+
+	seq = lp->tt.exch_seq_send(lp, fp, fc_fcp_srr_resp, NULL,
+				   fsp, jiffies_to_msecs(FC_SCSI_REC_TOV));
+	if (!seq) {
+		fc_frame_free(fp);
+		goto retry;
+	}
+	fsp->recov_seq = seq;
+	fsp->xfer_len = offset;
+	fsp->xfer_contig_end = offset;
+	fsp->state &= ~FC_SRB_RCV_STATUS;
+	fc_fcp_pkt_hold(fsp);		/* hold for outstanding SRR */
+	return;
+retry:
+	fc_fcp_retry_cmd(fsp);
+}
+
+/*
+ * Handle response from SRR.
+ */
+static void fc_fcp_srr_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
+{
+	struct fc_fcp_pkt *fsp = arg;
+	struct fc_frame_header *fh;
+
+	if (IS_ERR(fp)) {
+		fc_fcp_srr_error(fsp, fp);
+		return;
+	}
+
+	if (fc_fcp_lock_pkt(fsp))
+		goto out;
+
+	fh = fc_frame_header_get(fp);
+	/*
+	 * BUG? fc_fcp_srr_error calls exch_done which would release
+	 * the ep. But if fc_fcp_srr_error had got -FC_EX_TIMEOUT,
+	 * then fc_exch_timeout would be sending an abort. The exch_done
+	 * call by fc_fcp_srr_error would prevent fc_exch.c from seeing
+	 * an abort response though.
+	 */
+	if (fh->fh_type == FC_TYPE_BLS) {
+		fc_fcp_unlock_pkt(fsp);
+		return;
+	}
+
+	fsp->recov_seq = NULL;
+	switch (fc_frame_payload_op(fp)) {
+	case ELS_LS_ACC:
+		fsp->recov_retry = 0;
+		fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
+		break;
+	case ELS_LS_RJT:
+	default:
+		fc_timeout_error(fsp);
+		break;
+	}
+	fc_fcp_unlock_pkt(fsp);
+	fsp->lp->tt.exch_done(seq);
+out:
+	fc_frame_free(fp);
+	fc_fcp_pkt_release(fsp);	/* drop hold for outstanding SRR */
+}
+
+static void fc_fcp_srr_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
+{
+	if (fc_fcp_lock_pkt(fsp))
+		goto out;
+	fsp->lp->tt.exch_done(fsp->recov_seq);
+	fsp->recov_seq = NULL;
+	switch (PTR_ERR(fp)) {
+	case -FC_EX_TIMEOUT:
+		if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
+			fc_fcp_rec(fsp);
+		else
+			fc_timeout_error(fsp);
+		break;
+	case -FC_EX_CLOSED:			/* e.g., link failure */
+		/* fall through */
+	default:
+		fc_fcp_retry_cmd(fsp);
+		break;
+	}
+	fc_fcp_unlock_pkt(fsp);
+out:
+	fc_fcp_pkt_release(fsp);	/* drop hold for outstanding SRR */
+}
+
+static inline int fc_fcp_lport_queue_ready(struct fc_lport *lp)
+{
+	/* lock ? */
+	return (lp->state == LPORT_ST_READY) && (lp->link_status & FC_LINK_UP);
+}
+
+/**
+ * fc_queuecommand - The queuecommand function of the scsi template
+ * @cmd:	struct scsi_cmnd to be executed
+ * @done:	Callback function to be called when cmd is completed
+ *
+ * this is the i/o strategy routine, called by the scsi layer
+ * this routine is called with holding the host_lock.
+ */
+int fc_queuecommand(struct scsi_cmnd *sc_cmd, void (*done)(struct scsi_cmnd *))
+{
+	struct fc_lport *lp;
+	struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
+	struct fc_fcp_pkt *fsp;
+	struct fc_rport_libfc_priv *rp;
+	int rval;
+	int rc = 0;
+	struct fcoe_dev_stats *stats;
+
+	lp = shost_priv(sc_cmd->device->host);
+
+	rval = fc_remote_port_chkready(rport);
+	if (rval) {
+		sc_cmd->result = rval;
+		done(sc_cmd);
+		goto out;
+	}
+
+	if (!*(struct fc_remote_port **)rport->dd_data) {
+		/*
+		 * rport is transitioning from blocked/deleted to
+		 * online
+		 */
+		sc_cmd->result = DID_IMM_RETRY << 16;
+		done(sc_cmd);
+		goto out;
+	}
+
+	rp = rport->dd_data;
+
+	if (!fc_fcp_lport_queue_ready(lp)) {
+		rc = SCSI_MLQUEUE_HOST_BUSY;
+		goto out;
+	}
+
+	fsp = fc_fcp_pkt_alloc(lp, GFP_ATOMIC);
+	if (fsp == NULL) {
+		rc = SCSI_MLQUEUE_HOST_BUSY;
+		goto out;
+	}
+
+	/*
+	 * build the libfc request pkt
+	 */
+	fsp->cmd = sc_cmd;	/* save the cmd */
+	fsp->lp = lp;		/* save the softc ptr */
+	fsp->rport = rport;	/* set the remote port ptr */
+	sc_cmd->scsi_done = done;
+
+	/*
+	 * set up the transfer length
+	 */
+	fsp->data_len = scsi_bufflen(sc_cmd);
+	fsp->xfer_len = 0;
+
+	/*
+	 * setup the data direction
+	 */
+	stats = lp->dev_stats[smp_processor_id()];
+	if (sc_cmd->sc_data_direction == DMA_FROM_DEVICE) {
+		fsp->req_flags = FC_SRB_READ;
+		stats->InputRequests++;
+		stats->InputMegabytes = fsp->data_len;
+	} else if (sc_cmd->sc_data_direction == DMA_TO_DEVICE) {
+		fsp->req_flags = FC_SRB_WRITE;
+		stats->OutputRequests++;
+		stats->OutputMegabytes = fsp->data_len;
+	} else {
+		fsp->req_flags = 0;
+		stats->ControlRequests++;
+	}
+
+	fsp->tgt_flags = rp->flags;
+
+	init_timer(&fsp->timer);
+	fsp->timer.data = (unsigned long)fsp;
+
+	/*
+	 * send it to the lower layer
+	 * if we get -1 return then put the request in the pending
+	 * queue.
+	 */
+	rval = fc_fcp_pkt_send(lp, fsp);
+	if (rval != 0) {
+		fsp->state = FC_SRB_FREE;
+		fc_fcp_pkt_release(fsp);
+		rc = SCSI_MLQUEUE_HOST_BUSY;
+	}
+out:
+	return rc;
+}
+EXPORT_SYMBOL(fc_queuecommand);
+
+/**
+ * fc_io_compl -  Handle responses for completed commands
+ * @fsp:	scsi packet
+ *
+ * Translates a error to a Linux SCSI error.
+ *
+ * The fcp packet lock must be held when calling.
+ */
+static void fc_io_compl(struct fc_fcp_pkt *fsp)
+{
+	struct fc_fcp_internal *si;
+	struct scsi_cmnd *sc_cmd;
+	struct fc_lport *lp;
+	unsigned long flags;
+
+	fsp->state |= FC_SRB_COMPL;
+	if (!(fsp->state & FC_SRB_FCP_PROCESSING_TMO)) {
+		spin_unlock_bh(&fsp->scsi_pkt_lock);
+		del_timer_sync(&fsp->timer);
+		spin_lock_bh(&fsp->scsi_pkt_lock);
+	}
+
+	lp = fsp->lp;
+	si = fc_get_scsi_internal(lp);
+	spin_lock_irqsave(lp->host->host_lock, flags);
+	if (!fsp->cmd) {
+		spin_unlock_irqrestore(lp->host->host_lock, flags);
+		return;
+	}
+
+	/*
+	 * if a command timed out while we had to try and throttle IO
+	 * and it is now getting cleaned up, then we are about to
+	 * try again so clear the throttled flag incase we get more
+	 * time outs.
+	 */
+	if (si->throttled && fsp->state & FC_SRB_NOMEM)
+		si->throttled = 0;
+
+	sc_cmd = fsp->cmd;
+	fsp->cmd = NULL;
+
+	if (!sc_cmd->SCp.ptr) {
+		spin_unlock_irqrestore(lp->host->host_lock, flags);
+		return;
+	}
+
+	CMD_SCSI_STATUS(sc_cmd) = fsp->cdb_status;
+	switch (fsp->status_code) {
+	case FC_COMPLETE:
+		if (fsp->cdb_status == 0) {
+			/*
+			 * good I/O status
+			 */
+			sc_cmd->result = DID_OK << 16;
+			if (fsp->scsi_resid)
+				CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
+		} else if (fsp->cdb_status == QUEUE_FULL) {
+			struct scsi_device *tmp_sdev;
+			struct scsi_device *sdev = sc_cmd->device;
+
+			shost_for_each_device(tmp_sdev, sdev->host) {
+				if (tmp_sdev->id != sdev->id)
+					continue;
+
+				if (tmp_sdev->queue_depth > 1) {
+					scsi_track_queue_full(tmp_sdev,
+							      tmp_sdev->
+							      queue_depth - 1);
+				}
+			}
+			sc_cmd->result = (DID_OK << 16) | fsp->cdb_status;
+		} else {
+			/*
+			 * transport level I/O was ok but scsi
+			 * has non zero status
+			 */
+			sc_cmd->result = (DID_OK << 16) | fsp->cdb_status;
+		}
+		break;
+	case FC_ERROR:
+		sc_cmd->result = DID_ERROR << 16;
+		break;
+	case FC_DATA_UNDRUN:
+		if (fsp->cdb_status == 0) {
+			/*
+			 * scsi status is good but transport level
+			 * underrun. for read it should be an error??
+			 */
+			sc_cmd->result = (DID_OK << 16) | fsp->cdb_status;
+		} else {
+			/*
+			 * scsi got underrun, this is an error
+			 */
+			CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
+			sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
+		}
+		break;
+	case FC_DATA_OVRRUN:
+		/*
+		 * overrun is an error
+		 */
+		sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
+		break;
+	case FC_CMD_ABORTED:
+		sc_cmd->result = (DID_ABORT << 16) | fsp->io_status;
+		break;
+	case FC_CMD_TIME_OUT:
+		sc_cmd->result = (DID_BUS_BUSY << 16) | fsp->io_status;
+		break;
+	case FC_CMD_RESET:
+		sc_cmd->result = (DID_RESET << 16);
+		break;
+	case FC_HRD_ERROR:
+		sc_cmd->result = (DID_NO_CONNECT << 16);
+		break;
+	default:
+		sc_cmd->result = (DID_ERROR << 16);
+		break;
+	}
+
+	list_del(&fsp->list);
+	sc_cmd->SCp.ptr = NULL;
+	sc_cmd->scsi_done(sc_cmd);
+	spin_unlock_irqrestore(lp->host->host_lock, flags);
+
+	/* release ref from initial allocation in queue command */
+	fc_fcp_pkt_release(fsp);
+}
+
+/**
+ * fc_fcp_complete - complete processing of a fcp packet
+ * @fsp:	fcp packet
+ *
+ * This function may sleep if a fsp timer is pending.
+ * The host lock must not be held by caller.
+ */
+void fc_fcp_complete(struct fc_fcp_pkt *fsp)
+{
+	if (fc_fcp_lock_pkt(fsp))
+		return;
+
+	fc_fcp_complete_locked(fsp);
+	fc_fcp_unlock_pkt(fsp);
+}
+EXPORT_SYMBOL(fc_fcp_complete);
+
+/**
+ * fc_eh_abort - Abort a command...from scsi host template
+ * @sc_cmd:	scsi command to abort
+ *
+ * send ABTS to the target device  and wait for the response
+ * sc_cmd is the pointer to the command to be aborted.
+ */
+int fc_eh_abort(struct scsi_cmnd *sc_cmd)
+{
+	struct fc_fcp_pkt *fsp;
+	struct fc_lport *lp;
+	int rc = FAILED;
+	unsigned long flags;
+
+	lp = shost_priv(sc_cmd->device->host);
+	if (lp->state != LPORT_ST_READY)
+		return rc;
+	else if (!(lp->link_status & FC_LINK_UP))
+		return rc;
+
+	spin_lock_irqsave(lp->host->host_lock, flags);
+	fsp = CMD_SP(sc_cmd);
+	if (!fsp) {
+		/* command completed while scsi eh was setting up */
+		spin_unlock_irqrestore(lp->host->host_lock, flags);
+		return SUCCESS;
+	}
+	/* grab a ref so the fsp and sc_cmd cannot be relased from under us */
+	fc_fcp_pkt_hold(fsp);
+	spin_unlock_irqrestore(lp->host->host_lock, flags);
+
+	if (fc_fcp_lock_pkt(fsp)) {
+		/* completed while we were waiting for timer to be deleted */
+		rc = SUCCESS;
+		goto release_pkt;
+	}
+
+	rc = fc_fcp_pkt_abort(lp, fsp);
+	fc_fcp_unlock_pkt(fsp);
+
+release_pkt:
+	fc_fcp_pkt_release(fsp);
+	return rc;
+}
+EXPORT_SYMBOL(fc_eh_abort);
+
+/**
+ * fc_eh_device_reset: Reset a single LUN
+ * @sc_cmd:	scsi command
+ *
+ * Set from scsi host template to send tm cmd to the target and wait for the
+ * response.
+ */
+int fc_eh_device_reset(struct scsi_cmnd *sc_cmd)
+{
+	struct fc_lport *lp;
+	struct fc_fcp_pkt *fsp;
+	struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
+	int rc = FAILED;
+	struct fc_rport_libfc_priv *rp;
+	int rval;
+
+	rval = fc_remote_port_chkready(rport);
+	if (rval)
+		goto out;
+
+	rp = rport->dd_data;
+	lp = shost_priv(sc_cmd->device->host);
+
+	if (lp->state != LPORT_ST_READY)
+		return rc;
+
+	fsp = fc_fcp_pkt_alloc(lp, GFP_NOIO);
+	if (fsp == NULL) {
+		FC_DBG("could not allocate scsi_pkt\n");
+		sc_cmd->result = DID_NO_CONNECT << 16;
+		goto out;
+	}
+
+	/*
+	 * Build the libfc request pkt. Do not set the scsi cmnd, because
+	 * the sc passed in is not setup for execution like when sent
+	 * through the queuecommand callout.
+	 */
+	fsp->lp = lp;		/* save the softc ptr */
+	fsp->rport = rport;	/* set the remote port ptr */
+
+	/*
+	 * flush outstanding commands
+	 */
+	rc = fc_lun_reset(lp, fsp, scmd_id(sc_cmd), sc_cmd->device->lun);
+	fsp->state = FC_SRB_FREE;
+	fc_fcp_pkt_release(fsp);
+
+out:
+	return rc;
+}
+EXPORT_SYMBOL(fc_eh_device_reset);
+
+/**
+ * fc_eh_host_reset - The reset function will reset the ports on the host.
+ * @sc_cmd:	scsi command
+ */
+int fc_eh_host_reset(struct scsi_cmnd *sc_cmd)
+{
+	struct Scsi_Host *shost = sc_cmd->device->host;
+	struct fc_lport *lp = shost_priv(shost);
+	unsigned long wait_tmo;
+
+	lp->tt.lport_reset(lp);
+	wait_tmo = jiffies + FC_HOST_RESET_TIMEOUT;
+	while (!fc_fcp_lport_queue_ready(lp) && time_before(jiffies, wait_tmo))
+		msleep(1000);
+
+	if (fc_fcp_lport_queue_ready(lp)) {
+		shost_printk(KERN_INFO, shost, "Host reset succeeded.\n");
+		return SUCCESS;
+	} else {
+		shost_printk(KERN_INFO, shost, "Host reset failed. "
+			     "lport not ready.\n");
+		return FAILED;
+	}
+}
+EXPORT_SYMBOL(fc_eh_host_reset);
+
+/**
+ * fc_slave_alloc - configure queue depth
+ * @sdev:	scsi device
+ *
+ * Configures queue depth based on host's cmd_per_len. If not set
+ * then we use the libfc default.
+ */
+int fc_slave_alloc(struct scsi_device *sdev)
+{
+	struct fc_rport *rport = starget_to_rport(scsi_target(sdev));
+	int queue_depth;
+
+	if (!rport || fc_remote_port_chkready(rport))
+		return -ENXIO;
+
+	if (sdev->tagged_supported) {
+		if (sdev->host->hostt->cmd_per_lun)
+			queue_depth = sdev->host->hostt->cmd_per_lun;
+		else
+			queue_depth = FC_FCP_DFLT_QUEUE_DEPTH;
+		scsi_activate_tcq(sdev, queue_depth);
+	}
+	return 0;
+}
+EXPORT_SYMBOL(fc_slave_alloc);
+
+int fc_change_queue_depth(struct scsi_device *sdev, int qdepth)
+{
+	scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth);
+	return sdev->queue_depth;
+}
+EXPORT_SYMBOL(fc_change_queue_depth);
+
+int fc_change_queue_type(struct scsi_device *sdev, int tag_type)
+{
+	if (sdev->tagged_supported) {
+		scsi_set_tag_type(sdev, tag_type);
+		if (tag_type)
+			scsi_activate_tcq(sdev, sdev->queue_depth);
+		else
+			scsi_deactivate_tcq(sdev, sdev->queue_depth);
+	} else
+		tag_type = 0;
+
+	return tag_type;
+}
+EXPORT_SYMBOL(fc_change_queue_type);
+
+void fc_fcp_destroy(struct fc_lport *lp)
+{
+	struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
+
+	if (!list_empty(&si->scsi_pkt_queue))
+		printk(KERN_ERR "Leaked scsi packets.\n");
+
+	mempool_destroy(si->scsi_pkt_pool);
+	kfree(si);
+	lp->scsi_priv = NULL;
+}
+EXPORT_SYMBOL(fc_fcp_destroy);
+
+int fc_fcp_init(struct fc_lport *lp)
+{
+	int rc;
+	struct fc_fcp_internal *si;
+
+	if (!lp->tt.fcp_cmd_send)
+		lp->tt.fcp_cmd_send = fc_fcp_cmd_send;
+
+	if (!lp->tt.fcp_cleanup)
+		lp->tt.fcp_cleanup = fc_fcp_cleanup;
+
+	if (!lp->tt.fcp_abort_io)
+		lp->tt.fcp_abort_io = fc_fcp_abort_io;
+
+	si = kzalloc(sizeof(struct fc_fcp_internal), GFP_KERNEL);
+	if (!si)
+		return -ENOMEM;
+	lp->scsi_priv = si;
+	INIT_LIST_HEAD(&si->scsi_pkt_queue);
+
+	si->scsi_pkt_pool = mempool_create_slab_pool(2, scsi_pkt_cachep);
+	if (!si->scsi_pkt_pool) {
+		rc = -ENOMEM;
+		goto free_internal;
+	}
+	return 0;
+
+free_internal:
+	kfree(si);
+	return rc;
+}
+EXPORT_SYMBOL(fc_fcp_init);
+
+static int __init libfc_init(void)
+{
+	int rc;
+
+	scsi_pkt_cachep = kmem_cache_create("libfc_fcp_pkt",
+					    sizeof(struct fc_fcp_pkt),
+					    0, SLAB_HWCACHE_ALIGN, NULL);
+	if (scsi_pkt_cachep == NULL) {
+		FC_DBG("Unable to allocate SRB cache...module load failed!");
+		return -ENOMEM;
+	}
+
+	rc = fc_setup_exch_mgr();
+	if (rc)
+		goto destroy_pkt_cache;
+
+	rc = fc_setup_rport();
+	if (rc)
+		goto destroy_em;
+
+	return rc;
+destroy_em:
+	fc_destroy_exch_mgr();
+destroy_pkt_cache:
+	kmem_cache_destroy(scsi_pkt_cachep);
+	return rc;
+}
+
+static void __exit libfc_exit(void)
+{
+	kmem_cache_destroy(scsi_pkt_cachep);
+	fc_destroy_exch_mgr();
+	fc_destroy_rport();
+}
+
+module_init(libfc_init);
+module_exit(libfc_exit);

drivers/scsi/libfc/fc_frame.c

···
+/*
+ * Copyright(c) 2007 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Maintained at www.Open-FCoE.org
+ */
+
+/*
+ * Frame allocation.
+ */
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/skbuff.h>
+#include <linux/crc32.h>
+
+#include <scsi/fc_frame.h>
+
+/*
+ * Check the CRC in a frame.
+ */
+u32 fc_frame_crc_check(struct fc_frame *fp)
+{
+	u32 crc;
+	u32 error;
+	const u8 *bp;
+	unsigned int len;
+
+	WARN_ON(!fc_frame_is_linear(fp));
+	fr_flags(fp) &= ~FCPHF_CRC_UNCHECKED;
+	len = (fr_len(fp) + 3) & ~3;	/* round up length to include fill */
+	bp = (const u8 *) fr_hdr(fp);
+	crc = ~crc32(~0, bp, len);
+	error = crc ^ fr_crc(fp);
+	return error;
+}
+EXPORT_SYMBOL(fc_frame_crc_check);
+
+/*
+ * Allocate a frame intended to be sent via fcoe_xmit.
+ * Get an sk_buff for the frame and set the length.
+ */
+struct fc_frame *__fc_frame_alloc(size_t len)
+{
+	struct fc_frame *fp;
+	struct sk_buff *skb;
+
+	WARN_ON((len % sizeof(u32)) != 0);
+	len += sizeof(struct fc_frame_header);
+	skb = dev_alloc_skb(len + FC_FRAME_HEADROOM + FC_FRAME_TAILROOM);
+	if (!skb)
+		return NULL;
+	fp = (struct fc_frame *) skb;
+	fc_frame_init(fp);
+	skb_reserve(skb, FC_FRAME_HEADROOM);
+	skb_put(skb, len);
+	return fp;
+}
+EXPORT_SYMBOL(__fc_frame_alloc);
+
+
+struct fc_frame *fc_frame_alloc_fill(struct fc_lport *lp, size_t payload_len)
+{
+	struct fc_frame *fp;
+	size_t fill;
+
+	fill = payload_len % 4;
+	if (fill != 0)
+		fill = 4 - fill;
+	fp = __fc_frame_alloc(payload_len + fill);
+	if (fp) {
+		memset((char *) fr_hdr(fp) + payload_len, 0, fill);
+		/* trim is OK, we just allocated it so there are no fragments */
+		skb_trim(fp_skb(fp),
+			 payload_len + sizeof(struct fc_frame_header));
+	}
+	return fp;
+}

drivers/scsi/libfc/fc_lport.c

···
+/*
+ * Copyright(c) 2007 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Maintained at www.Open-FCoE.org
+ */
+
+/*
+ * PORT LOCKING NOTES
+ *
+ * These comments only apply to the 'port code' which consists of the lport,
+ * disc and rport blocks.
+ *
+ * MOTIVATION
+ *
+ * The lport, disc and rport blocks all have mutexes that are used to protect
+ * those objects. The main motivation for these locks is to prevent from
+ * having an lport reset just before we send a frame. In that scenario the
+ * lport's FID would get set to zero and then we'd send a frame with an
+ * invalid SID. We also need to ensure that states don't change unexpectedly
+ * while processing another state.
+ *
+ * HEIRARCHY
+ *
+ * The following heirarchy defines the locking rules. A greater lock
+ * may be held before acquiring a lesser lock, but a lesser lock should never
+ * be held while attempting to acquire a greater lock. Here is the heirarchy-
+ *
+ * lport > disc, lport > rport, disc > rport
+ *
+ * CALLBACKS
+ *
+ * The callbacks cause complications with this scheme. There is a callback
+ * from the rport (to either lport or disc) and a callback from disc
+ * (to the lport).
+ *
+ * As rports exit the rport state machine a callback is made to the owner of
+ * the rport to notify success or failure. Since the callback is likely to
+ * cause the lport or disc to grab its lock we cannot hold the rport lock
+ * while making the callback. To ensure that the rport is not free'd while
+ * processing the callback the rport callbacks are serialized through a
+ * single-threaded workqueue. An rport would never be free'd while in a
+ * callback handler becuase no other rport work in this queue can be executed
+ * at the same time.
+ *
+ * When discovery succeeds or fails a callback is made to the lport as
+ * notification. Currently, succesful discovery causes the lport to take no
+ * action. A failure will cause the lport to reset. There is likely a circular
+ * locking problem with this implementation.
+ */
+
+/*
+ * LPORT LOCKING
+ *
+ * The critical sections protected by the lport's mutex are quite broad and
+ * may be improved upon in the future. The lport code and its locking doesn't
+ * influence the I/O path, so excessive locking doesn't penalize I/O
+ * performance.
+ *
+ * The strategy is to lock whenever processing a request or response. Note
+ * that every _enter_* function corresponds to a state change. They generally
+ * change the lports state and then send a request out on the wire. We lock
+ * before calling any of these functions to protect that state change. This
+ * means that the entry points into the lport block manage the locks while
+ * the state machine can transition between states (i.e. _enter_* functions)
+ * while always staying protected.
+ *
+ * When handling responses we also hold the lport mutex broadly. When the
+ * lport receives the response frame it locks the mutex and then calls the
+ * appropriate handler for the particuar response. Generally a response will
+ * trigger a state change and so the lock must already be held.
+ *
+ * Retries also have to consider the locking. The retries occur from a work
+ * context and the work function will lock the lport and then retry the state
+ * (i.e. _enter_* function).
+ */
+
+#include <linux/timer.h>
+#include <asm/unaligned.h>
+
+#include <scsi/fc/fc_gs.h>
+
+#include <scsi/libfc.h>
+#include <scsi/fc_encode.h>
+
+/* Fabric IDs to use for point-to-point mode, chosen on whims. */
+#define FC_LOCAL_PTP_FID_LO   0x010101
+#define FC_LOCAL_PTP_FID_HI   0x010102
+
+#define	DNS_DELAY	      3 /* Discovery delay after RSCN (in seconds)*/
+
+static int fc_lport_debug;
+
+#define FC_DEBUG_LPORT(fmt...)			\
+	do {					\
+		if (fc_lport_debug)		\
+			FC_DBG(fmt);		\
+	} while (0)
+
+static void fc_lport_error(struct fc_lport *, struct fc_frame *);
+
+static void fc_lport_enter_reset(struct fc_lport *);
+static void fc_lport_enter_flogi(struct fc_lport *);
+static void fc_lport_enter_dns(struct fc_lport *);
+static void fc_lport_enter_rpn_id(struct fc_lport *);
+static void fc_lport_enter_rft_id(struct fc_lport *);
+static void fc_lport_enter_scr(struct fc_lport *);
+static void fc_lport_enter_ready(struct fc_lport *);
+static void fc_lport_enter_logo(struct fc_lport *);
+
+static const char *fc_lport_state_names[] = {
+	[LPORT_ST_NONE] =     "none",
+	[LPORT_ST_FLOGI] =    "FLOGI",
+	[LPORT_ST_DNS] =      "dNS",
+	[LPORT_ST_RPN_ID] =   "RPN_ID",
+	[LPORT_ST_RFT_ID] =   "RFT_ID",
+	[LPORT_ST_SCR] =      "SCR",
+	[LPORT_ST_READY] =    "Ready",
+	[LPORT_ST_LOGO] =     "LOGO",
+	[LPORT_ST_RESET] =    "reset",
+};
+
+static int fc_frame_drop(struct fc_lport *lport, struct fc_frame *fp)
+{
+	fc_frame_free(fp);
+	return 0;
+}
+
+/**
+ * fc_lport_rport_callback - Event handler for rport events
+ * @lport: The lport which is receiving the event
+ * @rport: The rport which the event has occured on
+ * @event: The event that occured
+ *
+ * Locking Note: The rport lock should not be held when calling
+ *		 this function.
+ */
+static void fc_lport_rport_callback(struct fc_lport *lport,
+				    struct fc_rport *rport,
+				    enum fc_rport_event event)
+{
+	FC_DEBUG_LPORT("Received a %d event for port (%6x)\n", event,
+		       rport->port_id);
+
+	switch (event) {
+	case RPORT_EV_CREATED:
+		if (rport->port_id == FC_FID_DIR_SERV) {
+			mutex_lock(&lport->lp_mutex);
+			if (lport->state == LPORT_ST_DNS) {
+				lport->dns_rp = rport;
+				fc_lport_enter_rpn_id(lport);
+			} else {
+				FC_DEBUG_LPORT("Received an CREATED event on "
+					       "port (%6x) for the directory "
+					       "server, but the lport is not "
+					       "in the DNS state, it's in the "
+					       "%d state", rport->port_id,
+					       lport->state);
+				lport->tt.rport_logoff(rport);
+			}
+			mutex_unlock(&lport->lp_mutex);
+		} else
+			FC_DEBUG_LPORT("Received an event for port (%6x) "
+				       "which is not the directory server\n",
+				       rport->port_id);
+		break;
+	case RPORT_EV_LOGO:
+	case RPORT_EV_FAILED:
+	case RPORT_EV_STOP:
+		if (rport->port_id == FC_FID_DIR_SERV) {
+			mutex_lock(&lport->lp_mutex);
+			lport->dns_rp = NULL;
+			mutex_unlock(&lport->lp_mutex);
+
+		} else
+			FC_DEBUG_LPORT("Received an event for port (%6x) "
+				       "which is not the directory server\n",
+				       rport->port_id);
+		break;
+	case RPORT_EV_NONE:
+		break;
+	}
+}
+
+/**
+ * fc_lport_state - Return a string which represents the lport's state
+ * @lport: The lport whose state is to converted to a string
+ */
+static const char *fc_lport_state(struct fc_lport *lport)
+{
+	const char *cp;
+
+	cp = fc_lport_state_names[lport->state];
+	if (!cp)
+		cp = "unknown";
+	return cp;
+}
+
+/**
+ * fc_lport_ptp_setup - Create an rport for point-to-point mode
+ * @lport: The lport to attach the ptp rport to
+ * @fid: The FID of the ptp rport
+ * @remote_wwpn: The WWPN of the ptp rport
+ * @remote_wwnn: The WWNN of the ptp rport
+ */
+static void fc_lport_ptp_setup(struct fc_lport *lport,
+			       u32 remote_fid, u64 remote_wwpn,
+			       u64 remote_wwnn)
+{
+	struct fc_disc_port dp;
+
+	dp.lp = lport;
+	dp.ids.port_id = remote_fid;
+	dp.ids.port_name = remote_wwpn;
+	dp.ids.node_name = remote_wwnn;
+	dp.ids.roles = FC_RPORT_ROLE_UNKNOWN;
+
+	if (lport->ptp_rp) {
+		lport->tt.rport_logoff(lport->ptp_rp);
+		lport->ptp_rp = NULL;
+	}
+
+	lport->ptp_rp = fc_rport_rogue_create(&dp);
+
+	lport->tt.rport_login(lport->ptp_rp);
+
+	fc_lport_enter_ready(lport);
+}
+
+void fc_get_host_port_type(struct Scsi_Host *shost)
+{
+	/* TODO - currently just NPORT */
+	fc_host_port_type(shost) = FC_PORTTYPE_NPORT;
+}
+EXPORT_SYMBOL(fc_get_host_port_type);
+
+void fc_get_host_port_state(struct Scsi_Host *shost)
+{
+	struct fc_lport *lp = shost_priv(shost);
+
+	if ((lp->link_status & FC_LINK_UP) == FC_LINK_UP)
+		fc_host_port_state(shost) = FC_PORTSTATE_ONLINE;
+	else
+		fc_host_port_state(shost) = FC_PORTSTATE_OFFLINE;
+}
+EXPORT_SYMBOL(fc_get_host_port_state);
+
+void fc_get_host_speed(struct Scsi_Host *shost)
+{
+	struct fc_lport *lport = shost_priv(shost);
+
+	fc_host_speed(shost) = lport->link_speed;
+}
+EXPORT_SYMBOL(fc_get_host_speed);
+
+struct fc_host_statistics *fc_get_host_stats(struct Scsi_Host *shost)
+{
+	int i;
+	struct fc_host_statistics *fcoe_stats;
+	struct fc_lport *lp = shost_priv(shost);
+	struct timespec v0, v1;
+
+	fcoe_stats = &lp->host_stats;
+	memset(fcoe_stats, 0, sizeof(struct fc_host_statistics));
+
+	jiffies_to_timespec(jiffies, &v0);
+	jiffies_to_timespec(lp->boot_time, &v1);
+	fcoe_stats->seconds_since_last_reset = (v0.tv_sec - v1.tv_sec);
+
+	for_each_online_cpu(i) {
+		struct fcoe_dev_stats *stats = lp->dev_stats[i];
+		if (stats == NULL)
+			continue;
+		fcoe_stats->tx_frames += stats->TxFrames;
+		fcoe_stats->tx_words += stats->TxWords;
+		fcoe_stats->rx_frames += stats->RxFrames;
+		fcoe_stats->rx_words += stats->RxWords;
+		fcoe_stats->error_frames += stats->ErrorFrames;
+		fcoe_stats->invalid_crc_count += stats->InvalidCRCCount;
+		fcoe_stats->fcp_input_requests += stats->InputRequests;
+		fcoe_stats->fcp_output_requests += stats->OutputRequests;
+		fcoe_stats->fcp_control_requests += stats->ControlRequests;
+		fcoe_stats->fcp_input_megabytes += stats->InputMegabytes;
+		fcoe_stats->fcp_output_megabytes += stats->OutputMegabytes;
+		fcoe_stats->link_failure_count += stats->LinkFailureCount;
+	}
+	fcoe_stats->lip_count = -1;
+	fcoe_stats->nos_count = -1;
+	fcoe_stats->loss_of_sync_count = -1;
+	fcoe_stats->loss_of_signal_count = -1;
+	fcoe_stats->prim_seq_protocol_err_count = -1;
+	fcoe_stats->dumped_frames = -1;
+	return fcoe_stats;
+}
+EXPORT_SYMBOL(fc_get_host_stats);
+
+/*
+ * Fill in FLOGI command for request.
+ */
+static void
+fc_lport_flogi_fill(struct fc_lport *lport, struct fc_els_flogi *flogi,
+		    unsigned int op)
+{
+	struct fc_els_csp *sp;
+	struct fc_els_cssp *cp;
+
+	memset(flogi, 0, sizeof(*flogi));
+	flogi->fl_cmd = (u8) op;
+	put_unaligned_be64(lport->wwpn, &flogi->fl_wwpn);
+	put_unaligned_be64(lport->wwnn, &flogi->fl_wwnn);
+	sp = &flogi->fl_csp;
+	sp->sp_hi_ver = 0x20;
+	sp->sp_lo_ver = 0x20;
+	sp->sp_bb_cred = htons(10);	/* this gets set by gateway */
+	sp->sp_bb_data = htons((u16) lport->mfs);
+	cp = &flogi->fl_cssp[3 - 1];	/* class 3 parameters */
+	cp->cp_class = htons(FC_CPC_VALID | FC_CPC_SEQ);
+	if (op != ELS_FLOGI) {
+		sp->sp_features = htons(FC_SP_FT_CIRO);
+		sp->sp_tot_seq = htons(255);	/* seq. we accept */
+		sp->sp_rel_off = htons(0x1f);
+		sp->sp_e_d_tov = htonl(lport->e_d_tov);
+
+		cp->cp_rdfs = htons((u16) lport->mfs);
+		cp->cp_con_seq = htons(255);
+		cp->cp_open_seq = 1;
+	}
+}
+
+/*
+ * Add a supported FC-4 type.
+ */
+static void fc_lport_add_fc4_type(struct fc_lport *lport, enum fc_fh_type type)
+{
+	__be32 *mp;
+
+	mp = &lport->fcts.ff_type_map[type / FC_NS_BPW];
+	*mp = htonl(ntohl(*mp) | 1UL << (type % FC_NS_BPW));
+}
+
+/**
+ * fc_lport_recv_rlir_req - Handle received Registered Link Incident Report.
+ * @lport: Fibre Channel local port recieving the RLIR
+ * @sp: current sequence in the RLIR exchange
+ * @fp: RLIR request frame
+ *
+ * Locking Note: The lport lock is exected to be held before calling
+ * this function.
+ */
+static void fc_lport_recv_rlir_req(struct fc_seq *sp, struct fc_frame *fp,
+				   struct fc_lport *lport)
+{
+	FC_DEBUG_LPORT("Received RLIR request while in state %s\n",
+		       fc_lport_state(lport));
+
+	lport->tt.seq_els_rsp_send(sp, ELS_LS_ACC, NULL);
+	fc_frame_free(fp);
+}
+
+/**
+ * fc_lport_recv_echo_req - Handle received ECHO request
+ * @lport: Fibre Channel local port recieving the ECHO
+ * @sp: current sequence in the ECHO exchange
+ * @fp: ECHO request frame
+ *
+ * Locking Note: The lport lock is exected to be held before calling
+ * this function.
+ */
+static void fc_lport_recv_echo_req(struct fc_seq *sp, struct fc_frame *in_fp,
+				   struct fc_lport *lport)
+{
+	struct fc_frame *fp;
+	struct fc_exch *ep = fc_seq_exch(sp);
+	unsigned int len;
+	void *pp;
+	void *dp;
+	u32 f_ctl;
+
+	FC_DEBUG_LPORT("Received RLIR request while in state %s\n",
+		       fc_lport_state(lport));
+
+	len = fr_len(in_fp) - sizeof(struct fc_frame_header);
+	pp = fc_frame_payload_get(in_fp, len);
+
+	if (len < sizeof(__be32))
+		len = sizeof(__be32);
+
+	fp = fc_frame_alloc(lport, len);
+	if (fp) {
+		dp = fc_frame_payload_get(fp, len);
+		memcpy(dp, pp, len);
+		*((u32 *)dp) = htonl(ELS_LS_ACC << 24);
+		sp = lport->tt.seq_start_next(sp);
+		f_ctl = FC_FC_EX_CTX | FC_FC_LAST_SEQ | FC_FC_END_SEQ;
+		fc_fill_fc_hdr(fp, FC_RCTL_ELS_REP, ep->did, ep->sid,
+			       FC_TYPE_ELS, f_ctl, 0);
+		lport->tt.seq_send(lport, sp, fp);
+	}
+	fc_frame_free(in_fp);
+}
+
+/**
+ * fc_lport_recv_echo_req - Handle received Request Node ID data request
+ * @lport: Fibre Channel local port recieving the RNID
+ * @sp: current sequence in the RNID exchange
+ * @fp: RNID request frame
+ *
+ * Locking Note: The lport lock is exected to be held before calling
+ * this function.
+ */
+static void fc_lport_recv_rnid_req(struct fc_seq *sp, struct fc_frame *in_fp,
+				   struct fc_lport *lport)
+{
+	struct fc_frame *fp;
+	struct fc_exch *ep = fc_seq_exch(sp);
+	struct fc_els_rnid *req;
+	struct {
+		struct fc_els_rnid_resp rnid;
+		struct fc_els_rnid_cid cid;
+		struct fc_els_rnid_gen gen;
+	} *rp;
+	struct fc_seq_els_data rjt_data;
+	u8 fmt;
+	size_t len;
+	u32 f_ctl;
+
+	FC_DEBUG_LPORT("Received RNID request while in state %s\n",
+		       fc_lport_state(lport));
+
+	req = fc_frame_payload_get(in_fp, sizeof(*req));
+	if (!req) {
+		rjt_data.fp = NULL;
+		rjt_data.reason = ELS_RJT_LOGIC;
+		rjt_data.explan = ELS_EXPL_NONE;
+		lport->tt.seq_els_rsp_send(sp, ELS_LS_RJT, &rjt_data);
+	} else {
+		fmt = req->rnid_fmt;
+		len = sizeof(*rp);
+		if (fmt != ELS_RNIDF_GEN ||
+		    ntohl(lport->rnid_gen.rnid_atype) == 0) {
+			fmt = ELS_RNIDF_NONE;	/* nothing to provide */
+			len -= sizeof(rp->gen);
+		}
+		fp = fc_frame_alloc(lport, len);
+		if (fp) {
+			rp = fc_frame_payload_get(fp, len);
+			memset(rp, 0, len);
+			rp->rnid.rnid_cmd = ELS_LS_ACC;
+			rp->rnid.rnid_fmt = fmt;
+			rp->rnid.rnid_cid_len = sizeof(rp->cid);
+			rp->cid.rnid_wwpn = htonll(lport->wwpn);
+			rp->cid.rnid_wwnn = htonll(lport->wwnn);
+			if (fmt == ELS_RNIDF_GEN) {
+				rp->rnid.rnid_sid_len = sizeof(rp->gen);
+				memcpy(&rp->gen, &lport->rnid_gen,
+				       sizeof(rp->gen));
+			}
+			sp = lport->tt.seq_start_next(sp);
+			f_ctl = FC_FC_EX_CTX | FC_FC_LAST_SEQ;
+			f_ctl |= FC_FC_END_SEQ | FC_FC_SEQ_INIT;
+			fc_fill_fc_hdr(fp, FC_RCTL_ELS_REP, ep->did, ep->sid,
+				       FC_TYPE_ELS, f_ctl, 0);
+			lport->tt.seq_send(lport, sp, fp);
+		}
+	}
+	fc_frame_free(in_fp);
+}
+
+/**
+ * fc_lport_recv_adisc_req - Handle received Address Discovery Request
+ * @lport: Fibre Channel local port recieving the ADISC
+ * @sp: current sequence in the ADISC exchange
+ * @fp: ADISC request frame
+ *
+ * Locking Note: The lport lock is expected to be held before calling
+ * this function.
+ */
+static void fc_lport_recv_adisc_req(struct fc_seq *sp, struct fc_frame *in_fp,
+				    struct fc_lport *lport)
+{
+	struct fc_frame *fp;
+	struct fc_exch *ep = fc_seq_exch(sp);
+	struct fc_els_adisc *req, *rp;
+	struct fc_seq_els_data rjt_data;
+	size_t len;
+	u32 f_ctl;
+
+	FC_DEBUG_LPORT("Received ADISC request while in state %s\n",
+		       fc_lport_state(lport));
+
+	req = fc_frame_payload_get(in_fp, sizeof(*req));
+	if (!req) {
+		rjt_data.fp = NULL;
+		rjt_data.reason = ELS_RJT_LOGIC;
+		rjt_data.explan = ELS_EXPL_NONE;
+		lport->tt.seq_els_rsp_send(sp, ELS_LS_RJT, &rjt_data);
+	} else {
+		len = sizeof(*rp);
+		fp = fc_frame_alloc(lport, len);
+		if (fp) {
+			rp = fc_frame_payload_get(fp, len);
+			memset(rp, 0, len);
+			rp->adisc_cmd = ELS_LS_ACC;
+			rp->adisc_wwpn = htonll(lport->wwpn);
+			rp->adisc_wwnn = htonll(lport->wwnn);
+			hton24(rp->adisc_port_id,
+			       fc_host_port_id(lport->host));
+			sp = lport->tt.seq_start_next(sp);
+			f_ctl = FC_FC_EX_CTX | FC_FC_LAST_SEQ;
+			f_ctl |= FC_FC_END_SEQ | FC_FC_SEQ_INIT;
+			fc_fill_fc_hdr(fp, FC_RCTL_ELS_REP, ep->did, ep->sid,
+				       FC_TYPE_ELS, f_ctl, 0);
+			lport->tt.seq_send(lport, sp, fp);
+		}
+	}
+	fc_frame_free(in_fp);
+}
+
+/**
+ * fc_lport_recv_logo_req - Handle received fabric LOGO request
+ * @lport: Fibre Channel local port recieving the LOGO
+ * @sp: current sequence in the LOGO exchange
+ * @fp: LOGO request frame
+ *
+ * Locking Note: The lport lock is exected to be held before calling
+ * this function.
+ */
+static void fc_lport_recv_logo_req(struct fc_seq *sp, struct fc_frame *fp,
+				   struct fc_lport *lport)
+{
+	lport->tt.seq_els_rsp_send(sp, ELS_LS_ACC, NULL);
+	fc_lport_enter_reset(lport);
+	fc_frame_free(fp);
+}
+
+/**
+ * fc_fabric_login - Start the lport state machine
+ * @lport: The lport that should log into the fabric
+ *
+ * Locking Note: This function should not be called
+ *		 with the lport lock held.
+ */
+int fc_fabric_login(struct fc_lport *lport)
+{
+	int rc = -1;
+
+	mutex_lock(&lport->lp_mutex);
+	if (lport->state == LPORT_ST_NONE) {
+		fc_lport_enter_reset(lport);
+		rc = 0;
+	}
+	mutex_unlock(&lport->lp_mutex);
+
+	return rc;
+}
+EXPORT_SYMBOL(fc_fabric_login);
+
+/**
+ * fc_linkup - Handler for transport linkup events
+ * @lport: The lport whose link is up
+ */
+void fc_linkup(struct fc_lport *lport)
+{
+	FC_DEBUG_LPORT("Link is up for port (%6x)\n",
+		       fc_host_port_id(lport->host));
+
+	mutex_lock(&lport->lp_mutex);
+	if ((lport->link_status & FC_LINK_UP) != FC_LINK_UP) {
+		lport->link_status |= FC_LINK_UP;
+
+		if (lport->state == LPORT_ST_RESET)
+			fc_lport_enter_flogi(lport);
+	}
+	mutex_unlock(&lport->lp_mutex);
+}
+EXPORT_SYMBOL(fc_linkup);
+
+/**
+ * fc_linkdown - Handler for transport linkdown events
+ * @lport: The lport whose link is down
+ */
+void fc_linkdown(struct fc_lport *lport)
+{
+	mutex_lock(&lport->lp_mutex);
+	FC_DEBUG_LPORT("Link is down for port (%6x)\n",
+		       fc_host_port_id(lport->host));
+
+	if ((lport->link_status & FC_LINK_UP) == FC_LINK_UP) {
+		lport->link_status &= ~(FC_LINK_UP);
+		fc_lport_enter_reset(lport);
+		lport->tt.fcp_cleanup(lport);
+	}
+	mutex_unlock(&lport->lp_mutex);
+}
+EXPORT_SYMBOL(fc_linkdown);
+
+/**
+ * fc_pause - Pause the flow of frames
+ * @lport: The lport to be paused
+ */
+void fc_pause(struct fc_lport *lport)
+{
+	mutex_lock(&lport->lp_mutex);
+	lport->link_status |= FC_PAUSE;
+	mutex_unlock(&lport->lp_mutex);
+}
+EXPORT_SYMBOL(fc_pause);
+
+/**
+ * fc_unpause - Unpause the flow of frames
+ * @lport: The lport to be unpaused
+ */
+void fc_unpause(struct fc_lport *lport)
+{
+	mutex_lock(&lport->lp_mutex);
+	lport->link_status &= ~(FC_PAUSE);
+	mutex_unlock(&lport->lp_mutex);
+}
+EXPORT_SYMBOL(fc_unpause);
+
+/**
+ * fc_fabric_logoff - Logout of the fabric
+ * @lport:	      fc_lport pointer to logoff the fabric
+ *
+ * Return value:
+ *	0 for success, -1 for failure
+ **/
+int fc_fabric_logoff(struct fc_lport *lport)
+{
+	lport->tt.disc_stop_final(lport);
+	mutex_lock(&lport->lp_mutex);
+	fc_lport_enter_logo(lport);
+	mutex_unlock(&lport->lp_mutex);
+	return 0;
+}
+EXPORT_SYMBOL(fc_fabric_logoff);
+
+/**
+ * fc_lport_destroy - unregister a fc_lport
+ * @lport:	      fc_lport pointer to unregister
+ *
+ * Return value:
+ *	None
+ * Note:
+ * exit routine for fc_lport instance
+ * clean-up all the allocated memory
+ * and free up other system resources.
+ *
+ **/
+int fc_lport_destroy(struct fc_lport *lport)
+{
+	lport->tt.frame_send = fc_frame_drop;
+	lport->tt.fcp_abort_io(lport);
+	lport->tt.exch_mgr_reset(lport->emp, 0, 0);
+	return 0;
+}
+EXPORT_SYMBOL(fc_lport_destroy);
+
+/**
+ * fc_set_mfs - sets up the mfs for the corresponding fc_lport
+ * @lport: fc_lport pointer to unregister
+ * @mfs: the new mfs for fc_lport
+ *
+ * Set mfs for the given fc_lport to the new mfs.
+ *
+ * Return: 0 for success
+ *
+ **/
+int fc_set_mfs(struct fc_lport *lport, u32 mfs)
+{
+	unsigned int old_mfs;
+	int rc = -EINVAL;
+
+	mutex_lock(&lport->lp_mutex);
+
+	old_mfs = lport->mfs;
+
+	if (mfs >= FC_MIN_MAX_FRAME) {
+		mfs &= ~3;
+		if (mfs > FC_MAX_FRAME)
+			mfs = FC_MAX_FRAME;
+		mfs -= sizeof(struct fc_frame_header);
+		lport->mfs = mfs;
+		rc = 0;
+	}
+
+	if (!rc && mfs < old_mfs)
+		fc_lport_enter_reset(lport);
+
+	mutex_unlock(&lport->lp_mutex);
+
+	return rc;
+}
+EXPORT_SYMBOL(fc_set_mfs);
+
+/**
+ * fc_lport_disc_callback - Callback for discovery events
+ * @lport: FC local port
+ * @event: The discovery event
+ */
+void fc_lport_disc_callback(struct fc_lport *lport, enum fc_disc_event event)
+{
+	switch (event) {
+	case DISC_EV_SUCCESS:
+		FC_DEBUG_LPORT("Got a SUCCESS event for port (%6x)\n",
+			       fc_host_port_id(lport->host));
+		break;
+	case DISC_EV_FAILED:
+		FC_DEBUG_LPORT("Got a FAILED event for port (%6x)\n",
+			       fc_host_port_id(lport->host));
+		mutex_lock(&lport->lp_mutex);
+		fc_lport_enter_reset(lport);
+		mutex_unlock(&lport->lp_mutex);
+		break;
+	case DISC_EV_NONE:
+		WARN_ON(1);
+		break;
+	}
+}
+
+/**
+ * fc_rport_enter_ready - Enter the ready state and start discovery
+ * @lport: Fibre Channel local port that is ready
+ *
+ * Locking Note: The lport lock is expected to be held before calling
+ * this routine.
+ */
+static void fc_lport_enter_ready(struct fc_lport *lport)
+{
+	FC_DEBUG_LPORT("Port (%6x) entered Ready from state %s\n",
+		       fc_host_port_id(lport->host), fc_lport_state(lport));
+
+	fc_lport_state_enter(lport, LPORT_ST_READY);
+
+	lport->tt.disc_start(fc_lport_disc_callback, lport);
+}
+
+/**
+ * fc_lport_recv_flogi_req - Receive a FLOGI request
+ * @sp_in: The sequence the FLOGI is on
+ * @rx_fp: The frame the FLOGI is in
+ * @lport: The lport that recieved the request
+ *
+ * A received FLOGI request indicates a point-to-point connection.
+ * Accept it with the common service parameters indicating our N port.
+ * Set up to do a PLOGI if we have the higher-number WWPN.
+ *
+ * Locking Note: The lport lock is exected to be held before calling
+ * this function.
+ */
+static void fc_lport_recv_flogi_req(struct fc_seq *sp_in,
+				    struct fc_frame *rx_fp,
+				    struct fc_lport *lport)
+{
+	struct fc_frame *fp;
+	struct fc_frame_header *fh;
+	struct fc_seq *sp;
+	struct fc_exch *ep;
+	struct fc_els_flogi *flp;
+	struct fc_els_flogi *new_flp;
+	u64 remote_wwpn;
+	u32 remote_fid;
+	u32 local_fid;
+	u32 f_ctl;
+
+	FC_DEBUG_LPORT("Received FLOGI request while in state %s\n",
+		       fc_lport_state(lport));
+
+	fh = fc_frame_header_get(rx_fp);
+	remote_fid = ntoh24(fh->fh_s_id);
+	flp = fc_frame_payload_get(rx_fp, sizeof(*flp));
+	if (!flp)
+		goto out;
+	remote_wwpn = get_unaligned_be64(&flp->fl_wwpn);
+	if (remote_wwpn == lport->wwpn) {
+		FC_DBG("FLOGI from port with same WWPN %llx "
+		       "possible configuration error\n", remote_wwpn);
+		goto out;
+	}
+	FC_DBG("FLOGI from port WWPN %llx\n", remote_wwpn);
+
+	/*
+	 * XXX what is the right thing to do for FIDs?
+	 * The originator might expect our S_ID to be 0xfffffe.
+	 * But if so, both of us could end up with the same FID.
+	 */
+	local_fid = FC_LOCAL_PTP_FID_LO;
+	if (remote_wwpn < lport->wwpn) {
+		local_fid = FC_LOCAL_PTP_FID_HI;
+		if (!remote_fid || remote_fid == local_fid)
+			remote_fid = FC_LOCAL_PTP_FID_LO;
+	} else if (!remote_fid) {
+		remote_fid = FC_LOCAL_PTP_FID_HI;
+	}
+
+	fc_host_port_id(lport->host) = local_fid;
+
+	fp = fc_frame_alloc(lport, sizeof(*flp));
+	if (fp) {
+		sp = lport->tt.seq_start_next(fr_seq(rx_fp));
+		new_flp = fc_frame_payload_get(fp, sizeof(*flp));
+		fc_lport_flogi_fill(lport, new_flp, ELS_FLOGI);
+		new_flp->fl_cmd = (u8) ELS_LS_ACC;
+
+		/*
+		 * Send the response.  If this fails, the originator should
+		 * repeat the sequence.
+		 */
+		f_ctl = FC_FC_EX_CTX | FC_FC_LAST_SEQ | FC_FC_END_SEQ;
+		ep = fc_seq_exch(sp);
+		fc_fill_fc_hdr(fp, FC_RCTL_ELS_REP, ep->did, ep->sid,
+			       FC_TYPE_ELS, f_ctl, 0);
+		lport->tt.seq_send(lport, sp, fp);
+
+	} else {
+		fc_lport_error(lport, fp);
+	}
+	fc_lport_ptp_setup(lport, remote_fid, remote_wwpn,
+			   get_unaligned_be64(&flp->fl_wwnn));
+
+	lport->tt.disc_start(fc_lport_disc_callback, lport);
+
+out:
+	sp = fr_seq(rx_fp);
+	fc_frame_free(rx_fp);
+}
+
+/**
+ * fc_lport_recv_req - The generic lport request handler
+ * @lport: The lport that received the request
+ * @sp: The sequence the request is on
+ * @fp: The frame the request is in
+ *
+ * This function will see if the lport handles the request or
+ * if an rport should handle the request.
+ *
+ * Locking Note: This function should not be called with the lport
+ *		 lock held becuase it will grab the lock.
+ */
+static void fc_lport_recv_req(struct fc_lport *lport, struct fc_seq *sp,
+			      struct fc_frame *fp)
+{
+	struct fc_frame_header *fh = fc_frame_header_get(fp);
+	void (*recv) (struct fc_seq *, struct fc_frame *, struct fc_lport *);
+	struct fc_rport *rport;
+	u32 s_id;
+	u32 d_id;
+	struct fc_seq_els_data rjt_data;
+
+	mutex_lock(&lport->lp_mutex);
+
+	/*
+	 * Handle special ELS cases like FLOGI, LOGO, and
+	 * RSCN here.  These don't require a session.
+	 * Even if we had a session, it might not be ready.
+	 */
+	if (fh->fh_type == FC_TYPE_ELS && fh->fh_r_ctl == FC_RCTL_ELS_REQ) {
+		/*
+		 * Check opcode.
+		 */
+		recv = NULL;
+		switch (fc_frame_payload_op(fp)) {
+		case ELS_FLOGI:
+			recv = fc_lport_recv_flogi_req;
+			break;
+		case ELS_LOGO:
+			fh = fc_frame_header_get(fp);
+			if (ntoh24(fh->fh_s_id) == FC_FID_FLOGI)
+				recv = fc_lport_recv_logo_req;
+			break;
+		case ELS_RSCN:
+			recv = lport->tt.disc_recv_req;
+			break;
+		case ELS_ECHO:
+			recv = fc_lport_recv_echo_req;
+			break;
+		case ELS_RLIR:
+			recv = fc_lport_recv_rlir_req;
+			break;
+		case ELS_RNID:
+			recv = fc_lport_recv_rnid_req;
+			break;
+		case ELS_ADISC:
+			recv = fc_lport_recv_adisc_req;
+			break;
+		}
+
+		if (recv)
+			recv(sp, fp, lport);
+		else {
+			/*
+			 * Find session.
+			 * If this is a new incoming PLOGI, we won't find it.
+			 */
+			s_id = ntoh24(fh->fh_s_id);
+			d_id = ntoh24(fh->fh_d_id);
+
+			rport = lport->tt.rport_lookup(lport, s_id);
+			if (rport)
+				lport->tt.rport_recv_req(sp, fp, rport);
+			else {
+				rjt_data.fp = NULL;
+				rjt_data.reason = ELS_RJT_UNAB;
+				rjt_data.explan = ELS_EXPL_NONE;
+				lport->tt.seq_els_rsp_send(sp,
+							   ELS_LS_RJT,
+							   &rjt_data);
+				fc_frame_free(fp);
+			}
+		}
+	} else {
+		FC_DBG("dropping invalid frame (eof %x)\n", fr_eof(fp));
+		fc_frame_free(fp);
+	}
+	mutex_unlock(&lport->lp_mutex);
+
+	/*
+	 *  The common exch_done for all request may not be good
+	 *  if any request requires longer hold on exhange. XXX
+	 */
+	lport->tt.exch_done(sp);
+}
+
+/**
+ * fc_lport_reset - Reset an lport
+ * @lport: The lport which should be reset
+ *
+ * Locking Note: This functions should not be called with the
+ *		 lport lock held.
+ */
+int fc_lport_reset(struct fc_lport *lport)
+{
+	mutex_lock(&lport->lp_mutex);
+	fc_lport_enter_reset(lport);
+	mutex_unlock(&lport->lp_mutex);
+	return 0;
+}
+EXPORT_SYMBOL(fc_lport_reset);
+
+/**
+ * fc_rport_enter_reset - Reset the local port
+ * @lport: Fibre Channel local port to be reset
+ *
+ * Locking Note: The lport lock is expected to be held before calling
+ * this routine.
+ */
+static void fc_lport_enter_reset(struct fc_lport *lport)
+{
+	FC_DEBUG_LPORT("Port (%6x) entered RESET state from %s state\n",
+		       fc_host_port_id(lport->host), fc_lport_state(lport));
+
+	fc_lport_state_enter(lport, LPORT_ST_RESET);
+
+	if (lport->dns_rp)
+		lport->tt.rport_logoff(lport->dns_rp);
+
+	if (lport->ptp_rp) {
+		lport->tt.rport_logoff(lport->ptp_rp);
+		lport->ptp_rp = NULL;
+	}
+
+	lport->tt.disc_stop(lport);
+
+	lport->tt.exch_mgr_reset(lport->emp, 0, 0);
+	fc_host_fabric_name(lport->host) = 0;
+	fc_host_port_id(lport->host) = 0;
+
+	if ((lport->link_status & FC_LINK_UP) == FC_LINK_UP)
+		fc_lport_enter_flogi(lport);
+}
+
+/**
+ * fc_lport_error - Handler for any errors
+ * @lport: The fc_lport object
+ * @fp: The frame pointer
+ *
+ * If the error was caused by a resource allocation failure
+ * then wait for half a second and retry, otherwise retry
+ * after the e_d_tov time.
+ */
+static void fc_lport_error(struct fc_lport *lport, struct fc_frame *fp)
+{
+	unsigned long delay = 0;
+	FC_DEBUG_LPORT("Error %ld in state %s, retries %d\n",
+		       PTR_ERR(fp), fc_lport_state(lport),
+		       lport->retry_count);
+
+	if (!fp || PTR_ERR(fp) == -FC_EX_TIMEOUT) {
+		/*
+		 * Memory allocation failure, or the exchange timed out.
+		 *  Retry after delay
+		 */
+		if (lport->retry_count < lport->max_retry_count) {
+			lport->retry_count++;
+			if (!fp)
+				delay = msecs_to_jiffies(500);
+			else
+				delay =	msecs_to_jiffies(lport->e_d_tov);
+
+			schedule_delayed_work(&lport->retry_work, delay);
+		} else {
+			switch (lport->state) {
+			case LPORT_ST_NONE:
+			case LPORT_ST_READY:
+			case LPORT_ST_RESET:
+			case LPORT_ST_RPN_ID:
+			case LPORT_ST_RFT_ID:
+			case LPORT_ST_SCR:
+			case LPORT_ST_DNS:
+			case LPORT_ST_FLOGI:
+			case LPORT_ST_LOGO:
+				fc_lport_enter_reset(lport);
+				break;
+			}
+		}
+	}
+}
+
+/**
+ * fc_lport_rft_id_resp - Handle response to Register Fibre
+ *			  Channel Types by ID (RPN_ID) request
+ * @sp: current sequence in RPN_ID exchange
+ * @fp: response frame
+ * @lp_arg: Fibre Channel host port instance
+ *
+ * Locking Note: This function will be called without the lport lock
+ * held, but it will lock, call an _enter_* function or fc_lport_error
+ * and then unlock the lport.
+ */
+static void fc_lport_rft_id_resp(struct fc_seq *sp, struct fc_frame *fp,
+				 void *lp_arg)
+{
+	struct fc_lport *lport = lp_arg;
+	struct fc_frame_header *fh;
+	struct fc_ct_hdr *ct;
+
+	if (fp == ERR_PTR(-FC_EX_CLOSED))
+		return;
+
+	mutex_lock(&lport->lp_mutex);
+
+	FC_DEBUG_LPORT("Received a RFT_ID response\n");
+
+	if (lport->state != LPORT_ST_RFT_ID) {
+		FC_DBG("Received a RFT_ID response, but in state %s\n",
+		       fc_lport_state(lport));
+		goto out;
+	}
+
+	if (IS_ERR(fp)) {
+		fc_lport_error(lport, fp);
+		goto err;
+	}
+
+	fh = fc_frame_header_get(fp);
+	ct = fc_frame_payload_get(fp, sizeof(*ct));
+
+	if (fh && ct && fh->fh_type == FC_TYPE_CT &&
+	    ct->ct_fs_type == FC_FST_DIR &&
+	    ct->ct_fs_subtype == FC_NS_SUBTYPE &&
+	    ntohs(ct->ct_cmd) == FC_FS_ACC)
+		fc_lport_enter_scr(lport);
+	else
+		fc_lport_error(lport, fp);
+out:
+	fc_frame_free(fp);
+err:
+	mutex_unlock(&lport->lp_mutex);
+}
+
+/**
+ * fc_lport_rpn_id_resp - Handle response to Register Port
+ *			  Name by ID (RPN_ID) request
+ * @sp: current sequence in RPN_ID exchange
+ * @fp: response frame
+ * @lp_arg: Fibre Channel host port instance
+ *
+ * Locking Note: This function will be called without the lport lock
+ * held, but it will lock, call an _enter_* function or fc_lport_error
+ * and then unlock the lport.
+ */
+static void fc_lport_rpn_id_resp(struct fc_seq *sp, struct fc_frame *fp,
+				 void *lp_arg)
+{
+	struct fc_lport *lport = lp_arg;
+	struct fc_frame_header *fh;
+	struct fc_ct_hdr *ct;
+
+	if (fp == ERR_PTR(-FC_EX_CLOSED))
+		return;
+
+	mutex_lock(&lport->lp_mutex);
+
+	FC_DEBUG_LPORT("Received a RPN_ID response\n");
+
+	if (lport->state != LPORT_ST_RPN_ID) {
+		FC_DBG("Received a RPN_ID response, but in state %s\n",
+		       fc_lport_state(lport));
+		goto out;
+	}
+
+	if (IS_ERR(fp)) {
+		fc_lport_error(lport, fp);
+		goto err;
+	}
+
+	fh = fc_frame_header_get(fp);
+	ct = fc_frame_payload_get(fp, sizeof(*ct));
+	if (fh && ct && fh->fh_type == FC_TYPE_CT &&
+	    ct->ct_fs_type == FC_FST_DIR &&
+	    ct->ct_fs_subtype == FC_NS_SUBTYPE &&
+	    ntohs(ct->ct_cmd) == FC_FS_ACC)
+		fc_lport_enter_rft_id(lport);
+	else
+		fc_lport_error(lport, fp);
+
+out:
+	fc_frame_free(fp);
+err:
+	mutex_unlock(&lport->lp_mutex);
+}
+
+/**
+ * fc_lport_scr_resp - Handle response to State Change Register (SCR) request
+ * @sp: current sequence in SCR exchange
+ * @fp: response frame
+ * @lp_arg: Fibre Channel lport port instance that sent the registration request
+ *
+ * Locking Note: This function will be called without the lport lock
+ * held, but it will lock, call an _enter_* function or fc_lport_error
+ * and then unlock the lport.
+ */
+static void fc_lport_scr_resp(struct fc_seq *sp, struct fc_frame *fp,
+			      void *lp_arg)
+{
+	struct fc_lport *lport = lp_arg;
+	u8 op;
+
+	if (fp == ERR_PTR(-FC_EX_CLOSED))
+		return;
+
+	mutex_lock(&lport->lp_mutex);
+
+	FC_DEBUG_LPORT("Received a SCR response\n");
+
+	if (lport->state != LPORT_ST_SCR) {
+		FC_DBG("Received a SCR response, but in state %s\n",
+		       fc_lport_state(lport));
+		goto out;
+	}
+
+	if (IS_ERR(fp)) {
+		fc_lport_error(lport, fp);
+		goto err;
+	}
+
+	op = fc_frame_payload_op(fp);
+	if (op == ELS_LS_ACC)
+		fc_lport_enter_ready(lport);
+	else
+		fc_lport_error(lport, fp);
+
+out:
+	fc_frame_free(fp);
+err:
+	mutex_unlock(&lport->lp_mutex);
+}
+
+/**
+ * fc_lport_enter_scr - Send a State Change Register (SCR) request
+ * @lport: Fibre Channel local port to register for state changes
+ *
+ * Locking Note: The lport lock is expected to be held before calling
+ * this routine.
+ */
+static void fc_lport_enter_scr(struct fc_lport *lport)
+{
+	struct fc_frame *fp;
+
+	FC_DEBUG_LPORT("Port (%6x) entered SCR state from %s state\n",
+		       fc_host_port_id(lport->host), fc_lport_state(lport));
+
+	fc_lport_state_enter(lport, LPORT_ST_SCR);
+
+	fp = fc_frame_alloc(lport, sizeof(struct fc_els_scr));
+	if (!fp) {
+		fc_lport_error(lport, fp);
+		return;
+	}
+
+	if (!lport->tt.elsct_send(lport, NULL, fp, ELS_SCR,
+				  fc_lport_scr_resp, lport, lport->e_d_tov))
+		fc_lport_error(lport, fp);
+}
+
+/**
+ * fc_lport_enter_rft_id - Register FC4-types with the name server
+ * @lport: Fibre Channel local port to register
+ *
+ * Locking Note: The lport lock is expected to be held before calling
+ * this routine.
+ */
+static void fc_lport_enter_rft_id(struct fc_lport *lport)
+{
+	struct fc_frame *fp;
+	struct fc_ns_fts *lps;
+	int i;
+
+	FC_DEBUG_LPORT("Port (%6x) entered RFT_ID state from %s state\n",
+		       fc_host_port_id(lport->host), fc_lport_state(lport));
+
+	fc_lport_state_enter(lport, LPORT_ST_RFT_ID);
+
+	lps = &lport->fcts;
+	i = sizeof(lps->ff_type_map) / sizeof(lps->ff_type_map[0]);
+	while (--i >= 0)
+		if (ntohl(lps->ff_type_map[i]) != 0)
+			break;
+	if (i < 0) {
+		/* nothing to register, move on to SCR */
+		fc_lport_enter_scr(lport);
+		return;
+	}
+
+	fp = fc_frame_alloc(lport, sizeof(struct fc_ct_hdr) +
+			    sizeof(struct fc_ns_rft));
+	if (!fp) {
+		fc_lport_error(lport, fp);
+		return;
+	}
+
+	if (!lport->tt.elsct_send(lport, NULL, fp, FC_NS_RFT_ID,
+				  fc_lport_rft_id_resp,
+				  lport, lport->e_d_tov))
+		fc_lport_error(lport, fp);
+}
+
+/**
+ * fc_rport_enter_rft_id - Register port name with the name server
+ * @lport: Fibre Channel local port to register
+ *
+ * Locking Note: The lport lock is expected to be held before calling
+ * this routine.
+ */
+static void fc_lport_enter_rpn_id(struct fc_lport *lport)
+{
+	struct fc_frame *fp;
+
+	FC_DEBUG_LPORT("Port (%6x) entered RPN_ID state from %s state\n",
+		       fc_host_port_id(lport->host), fc_lport_state(lport));
+
+	fc_lport_state_enter(lport, LPORT_ST_RPN_ID);
+
+	fp = fc_frame_alloc(lport, sizeof(struct fc_ct_hdr) +
+			    sizeof(struct fc_ns_rn_id));
+	if (!fp) {
+		fc_lport_error(lport, fp);
+		return;
+	}
+
+	if (!lport->tt.elsct_send(lport, NULL, fp, FC_NS_RPN_ID,
+				  fc_lport_rpn_id_resp,
+				  lport, lport->e_d_tov))
+		fc_lport_error(lport, fp);
+}
+
+static struct fc_rport_operations fc_lport_rport_ops = {
+	.event_callback = fc_lport_rport_callback,
+};
+
+/**
+ * fc_rport_enter_dns - Create a rport to the name server
+ * @lport: Fibre Channel local port requesting a rport for the name server
+ *
+ * Locking Note: The lport lock is expected to be held before calling
+ * this routine.
+ */
+static void fc_lport_enter_dns(struct fc_lport *lport)
+{
+	struct fc_rport *rport;
+	struct fc_rport_libfc_priv *rdata;
+	struct fc_disc_port dp;
+
+	dp.ids.port_id = FC_FID_DIR_SERV;
+	dp.ids.port_name = -1;
+	dp.ids.node_name = -1;
+	dp.ids.roles = FC_RPORT_ROLE_UNKNOWN;
+	dp.lp = lport;
+
+	FC_DEBUG_LPORT("Port (%6x) entered DNS state from %s state\n",
+		       fc_host_port_id(lport->host), fc_lport_state(lport));
+
+	fc_lport_state_enter(lport, LPORT_ST_DNS);
+
+	rport = fc_rport_rogue_create(&dp);
+	if (!rport)
+		goto err;
+
+	rdata = rport->dd_data;
+	rdata->ops = &fc_lport_rport_ops;
+	lport->tt.rport_login(rport);
+	return;
+
+err:
+	fc_lport_error(lport, NULL);
+}
+
+/**
+ * fc_lport_timeout - Handler for the retry_work timer.
+ * @work: The work struct of the fc_lport
+ */
+static void fc_lport_timeout(struct work_struct *work)
+{
+	struct fc_lport *lport =
+		container_of(work, struct fc_lport,
+			     retry_work.work);
+
+	mutex_lock(&lport->lp_mutex);
+
+	switch (lport->state) {
+	case LPORT_ST_NONE:
+	case LPORT_ST_READY:
+	case LPORT_ST_RESET:
+		WARN_ON(1);
+		break;
+	case LPORT_ST_FLOGI:
+		fc_lport_enter_flogi(lport);
+		break;
+	case LPORT_ST_DNS:
+		fc_lport_enter_dns(lport);
+		break;
+	case LPORT_ST_RPN_ID:
+		fc_lport_enter_rpn_id(lport);
+		break;
+	case LPORT_ST_RFT_ID:
+		fc_lport_enter_rft_id(lport);
+		break;
+	case LPORT_ST_SCR:
+		fc_lport_enter_scr(lport);
+		break;
+	case LPORT_ST_LOGO:
+		fc_lport_enter_logo(lport);
+		break;
+	}
+
+	mutex_unlock(&lport->lp_mutex);
+}
+
+/**
+ * fc_lport_logo_resp - Handle response to LOGO request
+ * @sp: current sequence in LOGO exchange
+ * @fp: response frame
+ * @lp_arg: Fibre Channel lport port instance that sent the LOGO request
+ *
+ * Locking Note: This function will be called without the lport lock
+ * held, but it will lock, call an _enter_* function or fc_lport_error
+ * and then unlock the lport.
+ */
+static void fc_lport_logo_resp(struct fc_seq *sp, struct fc_frame *fp,
+			       void *lp_arg)
+{
+	struct fc_lport *lport = lp_arg;
+	u8 op;
+
+	if (fp == ERR_PTR(-FC_EX_CLOSED))
+		return;
+
+	mutex_lock(&lport->lp_mutex);
+
+	FC_DEBUG_LPORT("Received a LOGO response\n");
+
+	if (lport->state != LPORT_ST_LOGO) {
+		FC_DBG("Received a LOGO response, but in state %s\n",
+		       fc_lport_state(lport));
+		goto out;
+	}
+
+	if (IS_ERR(fp)) {
+		fc_lport_error(lport, fp);
+		goto err;
+	}
+
+	op = fc_frame_payload_op(fp);
+	if (op == ELS_LS_ACC)
+		fc_lport_enter_reset(lport);
+	else
+		fc_lport_error(lport, fp);
+
+out:
+	fc_frame_free(fp);
+err:
+	mutex_unlock(&lport->lp_mutex);
+}
+
+/**
+ * fc_rport_enter_logo - Logout of the fabric
+ * @lport: Fibre Channel local port to be logged out
+ *
+ * Locking Note: The lport lock is expected to be held before calling
+ * this routine.
+ */
+static void fc_lport_enter_logo(struct fc_lport *lport)
+{
+	struct fc_frame *fp;
+	struct fc_els_logo *logo;
+
+	FC_DEBUG_LPORT("Port (%6x) entered LOGO state from %s state\n",
+		       fc_host_port_id(lport->host), fc_lport_state(lport));
+
+	fc_lport_state_enter(lport, LPORT_ST_LOGO);
+
+	/* DNS session should be closed so we can release it here */
+	if (lport->dns_rp)
+		lport->tt.rport_logoff(lport->dns_rp);
+
+	fp = fc_frame_alloc(lport, sizeof(*logo));
+	if (!fp) {
+		fc_lport_error(lport, fp);
+		return;
+	}
+
+	if (!lport->tt.elsct_send(lport, NULL, fp, ELS_LOGO, fc_lport_logo_resp,
+				  lport, lport->e_d_tov))
+		fc_lport_error(lport, fp);
+}
+
+/**
+ * fc_lport_flogi_resp - Handle response to FLOGI request
+ * @sp: current sequence in FLOGI exchange
+ * @fp: response frame
+ * @lp_arg: Fibre Channel lport port instance that sent the FLOGI request
+ *
+ * Locking Note: This function will be called without the lport lock
+ * held, but it will lock, call an _enter_* function or fc_lport_error
+ * and then unlock the lport.
+ */
+static void fc_lport_flogi_resp(struct fc_seq *sp, struct fc_frame *fp,
+				void *lp_arg)
+{
+	struct fc_lport *lport = lp_arg;
+	struct fc_frame_header *fh;
+	struct fc_els_flogi *flp;
+	u32 did;
+	u16 csp_flags;
+	unsigned int r_a_tov;
+	unsigned int e_d_tov;
+	u16 mfs;
+
+	if (fp == ERR_PTR(-FC_EX_CLOSED))
+		return;
+
+	mutex_lock(&lport->lp_mutex);
+
+	FC_DEBUG_LPORT("Received a FLOGI response\n");
+
+	if (lport->state != LPORT_ST_FLOGI) {
+		FC_DBG("Received a FLOGI response, but in state %s\n",
+		       fc_lport_state(lport));
+		goto out;
+	}
+
+	if (IS_ERR(fp)) {
+		fc_lport_error(lport, fp);
+		goto err;
+	}
+
+	fh = fc_frame_header_get(fp);
+	did = ntoh24(fh->fh_d_id);
+	if (fc_frame_payload_op(fp) == ELS_LS_ACC && did != 0) {
+
+		FC_DEBUG_LPORT("Assigned fid %x\n", did);
+		fc_host_port_id(lport->host) = did;
+
+		flp = fc_frame_payload_get(fp, sizeof(*flp));
+		if (flp) {
+			mfs = ntohs(flp->fl_csp.sp_bb_data) &
+				FC_SP_BB_DATA_MASK;
+			if (mfs >= FC_SP_MIN_MAX_PAYLOAD &&
+			    mfs < lport->mfs)
+				lport->mfs = mfs;
+			csp_flags = ntohs(flp->fl_csp.sp_features);
+			r_a_tov = ntohl(flp->fl_csp.sp_r_a_tov);
+			e_d_tov = ntohl(flp->fl_csp.sp_e_d_tov);
+			if (csp_flags & FC_SP_FT_EDTR)
+				e_d_tov /= 1000000;
+			if ((csp_flags & FC_SP_FT_FPORT) == 0) {
+				if (e_d_tov > lport->e_d_tov)
+					lport->e_d_tov = e_d_tov;
+				lport->r_a_tov = 2 * e_d_tov;
+				FC_DBG("Point-to-Point mode\n");
+				fc_lport_ptp_setup(lport, ntoh24(fh->fh_s_id),
+						   get_unaligned_be64(
+							   &flp->fl_wwpn),
+						   get_unaligned_be64(
+							   &flp->fl_wwnn));
+			} else {
+				lport->e_d_tov = e_d_tov;
+				lport->r_a_tov = r_a_tov;
+				fc_host_fabric_name(lport->host) =
+					get_unaligned_be64(&flp->fl_wwnn);
+				fc_lport_enter_dns(lport);
+			}
+		}
+
+		if (flp) {
+			csp_flags = ntohs(flp->fl_csp.sp_features);
+			if ((csp_flags & FC_SP_FT_FPORT) == 0) {
+				lport->tt.disc_start(fc_lport_disc_callback,
+						     lport);
+			}
+		}
+	} else {
+		FC_DBG("bad FLOGI response\n");
+	}
+
+out:
+	fc_frame_free(fp);
+err:
+	mutex_unlock(&lport->lp_mutex);
+}
+
+/**
+ * fc_rport_enter_flogi - Send a FLOGI request to the fabric manager
+ * @lport: Fibre Channel local port to be logged in to the fabric
+ *
+ * Locking Note: The lport lock is expected to be held before calling
+ * this routine.
+ */
+void fc_lport_enter_flogi(struct fc_lport *lport)
+{
+	struct fc_frame *fp;
+
+	FC_DEBUG_LPORT("Processing FLOGI state\n");
+
+	fc_lport_state_enter(lport, LPORT_ST_FLOGI);
+
+	fp = fc_frame_alloc(lport, sizeof(struct fc_els_flogi));
+	if (!fp)
+		return fc_lport_error(lport, fp);
+
+	if (!lport->tt.elsct_send(lport, NULL, fp, ELS_FLOGI,
+				  fc_lport_flogi_resp, lport, lport->e_d_tov))
+		fc_lport_error(lport, fp);
+}
+
+/* Configure a fc_lport */
+int fc_lport_config(struct fc_lport *lport)
+{
+	INIT_DELAYED_WORK(&lport->retry_work, fc_lport_timeout);
+	mutex_init(&lport->lp_mutex);
+
+	fc_lport_state_enter(lport, LPORT_ST_NONE);
+
+	fc_lport_add_fc4_type(lport, FC_TYPE_FCP);
+	fc_lport_add_fc4_type(lport, FC_TYPE_CT);
+
+	return 0;
+}
+EXPORT_SYMBOL(fc_lport_config);
+
+int fc_lport_init(struct fc_lport *lport)
+{
+	if (!lport->tt.lport_recv)
+		lport->tt.lport_recv = fc_lport_recv_req;
+
+	if (!lport->tt.lport_reset)
+		lport->tt.lport_reset = fc_lport_reset;
+
+	fc_host_port_type(lport->host) = FC_PORTTYPE_NPORT;
+	fc_host_node_name(lport->host) = lport->wwnn;
+	fc_host_port_name(lport->host) = lport->wwpn;
+	fc_host_supported_classes(lport->host) = FC_COS_CLASS3;
+	memset(fc_host_supported_fc4s(lport->host), 0,
+	       sizeof(fc_host_supported_fc4s(lport->host)));
+	fc_host_supported_fc4s(lport->host)[2] = 1;
+	fc_host_supported_fc4s(lport->host)[7] = 1;
+
+	/* This value is also unchanging */
+	memset(fc_host_active_fc4s(lport->host), 0,
+	       sizeof(fc_host_active_fc4s(lport->host)));
+	fc_host_active_fc4s(lport->host)[2] = 1;
+	fc_host_active_fc4s(lport->host)[7] = 1;
+	fc_host_maxframe_size(lport->host) = lport->mfs;
+	fc_host_supported_speeds(lport->host) = 0;
+	if (lport->link_supported_speeds & FC_PORTSPEED_1GBIT)
+		fc_host_supported_speeds(lport->host) |= FC_PORTSPEED_1GBIT;
+	if (lport->link_supported_speeds & FC_PORTSPEED_10GBIT)
+		fc_host_supported_speeds(lport->host) |= FC_PORTSPEED_10GBIT;
+
+	return 0;
+}
+EXPORT_SYMBOL(fc_lport_init);

drivers/scsi/libfc/fc_rport.c

···
+/*
+ * Copyright(c) 2007 - 2008 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Maintained at www.Open-FCoE.org
+ */
+
+/*
+ * RPORT GENERAL INFO
+ *
+ * This file contains all processing regarding fc_rports. It contains the
+ * rport state machine and does all rport interaction with the transport class.
+ * There should be no other places in libfc that interact directly with the
+ * transport class in regards to adding and deleting rports.
+ *
+ * fc_rport's represent N_Port's within the fabric.
+ */
+
+/*
+ * RPORT LOCKING
+ *
+ * The rport should never hold the rport mutex and then attempt to acquire
+ * either the lport or disc mutexes. The rport's mutex is considered lesser
+ * than both the lport's mutex and the disc mutex. Refer to fc_lport.c for
+ * more comments on the heirarchy.
+ *
+ * The locking strategy is similar to the lport's strategy. The lock protects
+ * the rport's states and is held and released by the entry points to the rport
+ * block. All _enter_* functions correspond to rport states and expect the rport
+ * mutex to be locked before calling them. This means that rports only handle
+ * one request or response at a time, since they're not critical for the I/O
+ * path this potential over-use of the mutex is acceptable.
+ */
+
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/rcupdate.h>
+#include <linux/timer.h>
+#include <linux/workqueue.h>
+#include <asm/unaligned.h>
+
+#include <scsi/libfc.h>
+#include <scsi/fc_encode.h>
+
+static int fc_rport_debug;
+
+#define FC_DEBUG_RPORT(fmt...)			\
+	do {					\
+		if (fc_rport_debug)		\
+			FC_DBG(fmt);		\
+	} while (0)
+
+struct workqueue_struct *rport_event_queue;
+
+static void fc_rport_enter_plogi(struct fc_rport *);
+static void fc_rport_enter_prli(struct fc_rport *);
+static void fc_rport_enter_rtv(struct fc_rport *);
+static void fc_rport_enter_ready(struct fc_rport *);
+static void fc_rport_enter_logo(struct fc_rport *);
+
+static void fc_rport_recv_plogi_req(struct fc_rport *,
+				    struct fc_seq *, struct fc_frame *);
+static void fc_rport_recv_prli_req(struct fc_rport *,
+				   struct fc_seq *, struct fc_frame *);
+static void fc_rport_recv_prlo_req(struct fc_rport *,
+				   struct fc_seq *, struct fc_frame *);
+static void fc_rport_recv_logo_req(struct fc_rport *,
+				   struct fc_seq *, struct fc_frame *);
+static void fc_rport_timeout(struct work_struct *);
+static void fc_rport_error(struct fc_rport *, struct fc_frame *);
+static void fc_rport_work(struct work_struct *);
+
+static const char *fc_rport_state_names[] = {
+	[RPORT_ST_NONE] = "None",
+	[RPORT_ST_INIT] = "Init",
+	[RPORT_ST_PLOGI] = "PLOGI",
+	[RPORT_ST_PRLI] = "PRLI",
+	[RPORT_ST_RTV] = "RTV",
+	[RPORT_ST_READY] = "Ready",
+	[RPORT_ST_LOGO] = "LOGO",
+};
+
+static void fc_rport_rogue_destroy(struct device *dev)
+{
+	struct fc_rport *rport = dev_to_rport(dev);
+	FC_DEBUG_RPORT("Destroying rogue rport (%6x)\n", rport->port_id);
+	kfree(rport);
+}
+
+struct fc_rport *fc_rport_rogue_create(struct fc_disc_port *dp)
+{
+	struct fc_rport *rport;
+	struct fc_rport_libfc_priv *rdata;
+	rport = kzalloc(sizeof(*rport) + sizeof(*rdata), GFP_KERNEL);
+
+	if (!rport)
+		return NULL;
+
+	rdata = RPORT_TO_PRIV(rport);
+
+	rport->dd_data = rdata;
+	rport->port_id = dp->ids.port_id;
+	rport->port_name = dp->ids.port_name;
+	rport->node_name = dp->ids.node_name;
+	rport->roles = dp->ids.roles;
+	rport->maxframe_size = FC_MIN_MAX_PAYLOAD;
+	/*
+	 * Note: all this libfc rogue rport code will be removed for
+	 * upstream so it fine that this is really ugly and hacky right now.
+	 */
+	device_initialize(&rport->dev);
+	rport->dev.release = fc_rport_rogue_destroy;
+
+	mutex_init(&rdata->rp_mutex);
+	rdata->local_port = dp->lp;
+	rdata->trans_state = FC_PORTSTATE_ROGUE;
+	rdata->rp_state = RPORT_ST_INIT;
+	rdata->event = RPORT_EV_NONE;
+	rdata->flags = FC_RP_FLAGS_REC_SUPPORTED;
+	rdata->ops = NULL;
+	rdata->e_d_tov = dp->lp->e_d_tov;
+	rdata->r_a_tov = dp->lp->r_a_tov;
+	INIT_DELAYED_WORK(&rdata->retry_work, fc_rport_timeout);
+	INIT_WORK(&rdata->event_work, fc_rport_work);
+	/*
+	 * For good measure, but not necessary as we should only
+	 * add REAL rport to the lport list.
+	 */
+	INIT_LIST_HEAD(&rdata->peers);
+
+	return rport;
+}
+
+/**
+ * fc_rport_state - return a string for the state the rport is in
+ * @rport: The rport whose state we want to get a string for
+ */
+static const char *fc_rport_state(struct fc_rport *rport)
+{
+	const char *cp;
+	struct fc_rport_libfc_priv *rdata = rport->dd_data;
+
+	cp = fc_rport_state_names[rdata->rp_state];
+	if (!cp)
+		cp = "Unknown";
+	return cp;
+}
+
+/**
+ * fc_set_rport_loss_tmo - Set the remote port loss timeout in seconds.
+ * @rport: Pointer to Fibre Channel remote port structure
+ * @timeout: timeout in seconds
+ */
+void fc_set_rport_loss_tmo(struct fc_rport *rport, u32 timeout)
+{
+	if (timeout)
+		rport->dev_loss_tmo = timeout + 5;
+	else
+		rport->dev_loss_tmo = 30;
+}
+EXPORT_SYMBOL(fc_set_rport_loss_tmo);
+
+/**
+ * fc_plogi_get_maxframe - Get max payload from the common service parameters
+ * @flp: FLOGI payload structure
+ * @maxval: upper limit, may be less than what is in the service parameters
+ */
+static unsigned int
+fc_plogi_get_maxframe(struct fc_els_flogi *flp, unsigned int maxval)
+{
+	unsigned int mfs;
+
+	/*
+	 * Get max payload from the common service parameters and the
+	 * class 3 receive data field size.
+	 */
+	mfs = ntohs(flp->fl_csp.sp_bb_data) & FC_SP_BB_DATA_MASK;
+	if (mfs >= FC_SP_MIN_MAX_PAYLOAD && mfs < maxval)
+		maxval = mfs;
+	mfs = ntohs(flp->fl_cssp[3 - 1].cp_rdfs);
+	if (mfs >= FC_SP_MIN_MAX_PAYLOAD && mfs < maxval)
+		maxval = mfs;
+	return maxval;
+}
+
+/**
+ * fc_rport_state_enter - Change the rport's state
+ * @rport: The rport whose state should change
+ * @new: The new state of the rport
+ *
+ * Locking Note: Called with the rport lock held
+ */
+static void fc_rport_state_enter(struct fc_rport *rport,
+				 enum fc_rport_state new)
+{
+	struct fc_rport_libfc_priv *rdata = rport->dd_data;
+	if (rdata->rp_state != new)
+		rdata->retries = 0;
+	rdata->rp_state = new;
+}
+
+static void fc_rport_work(struct work_struct *work)
+{
+	struct fc_rport_libfc_priv *rdata =
+		container_of(work, struct fc_rport_libfc_priv, event_work);
+	enum fc_rport_event event;
+	enum fc_rport_trans_state trans_state;
+	struct fc_lport *lport = rdata->local_port;
+	struct fc_rport_operations *rport_ops;
+	struct fc_rport *rport = PRIV_TO_RPORT(rdata);
+
+	mutex_lock(&rdata->rp_mutex);
+	event = rdata->event;
+	rport_ops = rdata->ops;
+
+	if (event == RPORT_EV_CREATED) {
+		struct fc_rport *new_rport;
+		struct fc_rport_libfc_priv *new_rdata;
+		struct fc_rport_identifiers ids;
+
+		ids.port_id = rport->port_id;
+		ids.roles = rport->roles;
+		ids.port_name = rport->port_name;
+		ids.node_name = rport->node_name;
+
+		mutex_unlock(&rdata->rp_mutex);
+
+		new_rport = fc_remote_port_add(lport->host, 0, &ids);
+		if (new_rport) {
+			/*
+			 * Switch from the rogue rport to the rport
+			 * returned by the FC class.
+			 */
+			new_rport->maxframe_size = rport->maxframe_size;
+
+			new_rdata = new_rport->dd_data;
+			new_rdata->e_d_tov = rdata->e_d_tov;
+			new_rdata->r_a_tov = rdata->r_a_tov;
+			new_rdata->ops = rdata->ops;
+			new_rdata->local_port = rdata->local_port;
+			new_rdata->flags = FC_RP_FLAGS_REC_SUPPORTED;
+			new_rdata->trans_state = FC_PORTSTATE_REAL;
+			mutex_init(&new_rdata->rp_mutex);
+			INIT_DELAYED_WORK(&new_rdata->retry_work,
+					  fc_rport_timeout);
+			INIT_LIST_HEAD(&new_rdata->peers);
+			INIT_WORK(&new_rdata->event_work, fc_rport_work);
+
+			fc_rport_state_enter(new_rport, RPORT_ST_READY);
+		} else {
+			FC_DBG("Failed to create the rport for port "
+			       "(%6x).\n", ids.port_id);
+			event = RPORT_EV_FAILED;
+		}
+		put_device(&rport->dev);
+		rport = new_rport;
+		rdata = new_rport->dd_data;
+		if (rport_ops->event_callback)
+			rport_ops->event_callback(lport, rport, event);
+	} else if ((event == RPORT_EV_FAILED) ||
+		   (event == RPORT_EV_LOGO) ||
+		   (event == RPORT_EV_STOP)) {
+		trans_state = rdata->trans_state;
+		mutex_unlock(&rdata->rp_mutex);
+		if (rport_ops->event_callback)
+			rport_ops->event_callback(lport, rport, event);
+		if (trans_state == FC_PORTSTATE_ROGUE)
+			put_device(&rport->dev);
+		else
+			fc_remote_port_delete(rport);
+	} else
+		mutex_unlock(&rdata->rp_mutex);
+}
+
+/**
+ * fc_rport_login - Start the remote port login state machine
+ * @rport: Fibre Channel remote port
+ *
+ * Locking Note: Called without the rport lock held. This
+ * function will hold the rport lock, call an _enter_*
+ * function and then unlock the rport.
+ */
+int fc_rport_login(struct fc_rport *rport)
+{
+	struct fc_rport_libfc_priv *rdata = rport->dd_data;
+
+	mutex_lock(&rdata->rp_mutex);
+
+	FC_DEBUG_RPORT("Login to port (%6x)\n", rport->port_id);
+
+	fc_rport_enter_plogi(rport);
+
+	mutex_unlock(&rdata->rp_mutex);
+
+	return 0;
+}
+
+/**
+ * fc_rport_logoff - Logoff and remove an rport
+ * @rport: Fibre Channel remote port to be removed
+ *
+ * Locking Note: Called without the rport lock held. This
+ * function will hold the rport lock, call an _enter_*
+ * function and then unlock the rport.
+ */
+int fc_rport_logoff(struct fc_rport *rport)
+{
+	struct fc_rport_libfc_priv *rdata = rport->dd_data;
+
+	mutex_lock(&rdata->rp_mutex);
+
+	FC_DEBUG_RPORT("Remove port (%6x)\n", rport->port_id);
+
+	fc_rport_enter_logo(rport);
+
+	/*
+	 * Change the state to NONE so that we discard
+	 * the response.
+	 */
+	fc_rport_state_enter(rport, RPORT_ST_NONE);
+
+	mutex_unlock(&rdata->rp_mutex);
+
+	cancel_delayed_work_sync(&rdata->retry_work);
+
+	mutex_lock(&rdata->rp_mutex);
+
+	rdata->event = RPORT_EV_STOP;
+	queue_work(rport_event_queue, &rdata->event_work);
+
+	mutex_unlock(&rdata->rp_mutex);
+
+	return 0;
+}
+
+/**
+ * fc_rport_enter_ready - The rport is ready
+ * @rport: Fibre Channel remote port that is ready
+ *
+ * Locking Note: The rport lock is expected to be held before calling
+ * this routine.
+ */
+static void fc_rport_enter_ready(struct fc_rport *rport)
+{
+	struct fc_rport_libfc_priv *rdata = rport->dd_data;
+
+	fc_rport_state_enter(rport, RPORT_ST_READY);
+
+	FC_DEBUG_RPORT("Port (%6x) is Ready\n", rport->port_id);
+
+	rdata->event = RPORT_EV_CREATED;
+	queue_work(rport_event_queue, &rdata->event_work);
+}
+
+/**
+ * fc_rport_timeout - Handler for the retry_work timer.
+ * @work: The work struct of the fc_rport_libfc_priv
+ *
+ * Locking Note: Called without the rport lock held. This
+ * function will hold the rport lock, call an _enter_*
+ * function and then unlock the rport.
+ */
+static void fc_rport_timeout(struct work_struct *work)
+{
+	struct fc_rport_libfc_priv *rdata =
+		container_of(work, struct fc_rport_libfc_priv, retry_work.work);
+	struct fc_rport *rport = PRIV_TO_RPORT(rdata);
+
+	mutex_lock(&rdata->rp_mutex);
+
+	switch (rdata->rp_state) {
+	case RPORT_ST_PLOGI:
+		fc_rport_enter_plogi(rport);
+		break;
+	case RPORT_ST_PRLI:
+		fc_rport_enter_prli(rport);
+		break;
+	case RPORT_ST_RTV:
+		fc_rport_enter_rtv(rport);
+		break;
+	case RPORT_ST_LOGO:
+		fc_rport_enter_logo(rport);
+		break;
+	case RPORT_ST_READY:
+	case RPORT_ST_INIT:
+	case RPORT_ST_NONE:
+		break;
+	}
+
+	mutex_unlock(&rdata->rp_mutex);
+	put_device(&rport->dev);
+}
+
+/**
+ * fc_rport_error - Handler for any errors
+ * @rport: The fc_rport object
+ * @fp: The frame pointer
+ *
+ * If the error was caused by a resource allocation failure
+ * then wait for half a second and retry, otherwise retry
+ * immediately.
+ *
+ * Locking Note: The rport lock is expected to be held before
+ * calling this routine
+ */
+static void fc_rport_error(struct fc_rport *rport, struct fc_frame *fp)
+{
+	struct fc_rport_libfc_priv *rdata = rport->dd_data;
+	unsigned long delay = 0;
+
+	FC_DEBUG_RPORT("Error %ld in state %s, retries %d\n",
+		       PTR_ERR(fp), fc_rport_state(rport), rdata->retries);
+
+	if (!fp || PTR_ERR(fp) == -FC_EX_TIMEOUT) {
+		/*
+		 * Memory allocation failure, or the exchange timed out.
+		 *  Retry after delay
+		 */
+		if (rdata->retries < rdata->local_port->max_retry_count) {
+			rdata->retries++;
+			if (!fp)
+				delay = msecs_to_jiffies(500);
+			get_device(&rport->dev);
+			schedule_delayed_work(&rdata->retry_work, delay);
+		} else {
+			switch (rdata->rp_state) {
+			case RPORT_ST_PLOGI:
+			case RPORT_ST_PRLI:
+			case RPORT_ST_LOGO:
+				rdata->event = RPORT_EV_FAILED;
+				queue_work(rport_event_queue,
+					   &rdata->event_work);
+				break;
+			case RPORT_ST_RTV:
+				fc_rport_enter_ready(rport);
+				break;
+			case RPORT_ST_NONE:
+			case RPORT_ST_READY:
+			case RPORT_ST_INIT:
+				break;
+			}
+		}
+	}
+}
+
+/**
+ * fc_rport_plogi_recv_resp - Handle incoming ELS PLOGI response
+ * @sp: current sequence in the PLOGI exchange
+ * @fp: response frame
+ * @rp_arg: Fibre Channel remote port
+ *
+ * Locking Note: This function will be called without the rport lock
+ * held, but it will lock, call an _enter_* function or fc_rport_error
+ * and then unlock the rport.
+ */
+static void fc_rport_plogi_resp(struct fc_seq *sp, struct fc_frame *fp,
+				void *rp_arg)
+{
+	struct fc_rport *rport = rp_arg;
+	struct fc_rport_libfc_priv *rdata = rport->dd_data;
+	struct fc_lport *lport = rdata->local_port;
+	struct fc_els_flogi *plp;
+	unsigned int tov;
+	u16 csp_seq;
+	u16 cssp_seq;
+	u8 op;
+
+	mutex_lock(&rdata->rp_mutex);
+
+	FC_DEBUG_RPORT("Received a PLOGI response from port (%6x)\n",
+		       rport->port_id);
+
+	if (rdata->rp_state != RPORT_ST_PLOGI) {
+		FC_DBG("Received a PLOGI response, but in state %s\n",
+		       fc_rport_state(rport));
+		goto out;
+	}
+
+	if (IS_ERR(fp)) {
+		fc_rport_error(rport, fp);
+		goto err;
+	}
+
+	op = fc_frame_payload_op(fp);
+	if (op == ELS_LS_ACC &&
+	    (plp = fc_frame_payload_get(fp, sizeof(*plp))) != NULL) {
+		rport->port_name = get_unaligned_be64(&plp->fl_wwpn);
+		rport->node_name = get_unaligned_be64(&plp->fl_wwnn);
+
+		tov = ntohl(plp->fl_csp.sp_e_d_tov);
+		if (ntohs(plp->fl_csp.sp_features) & FC_SP_FT_EDTR)
+			tov /= 1000;
+		if (tov > rdata->e_d_tov)
+			rdata->e_d_tov = tov;
+		csp_seq = ntohs(plp->fl_csp.sp_tot_seq);
+		cssp_seq = ntohs(plp->fl_cssp[3 - 1].cp_con_seq);
+		if (cssp_seq < csp_seq)
+			csp_seq = cssp_seq;
+		rdata->max_seq = csp_seq;
+		rport->maxframe_size =
+			fc_plogi_get_maxframe(plp, lport->mfs);
+
+		/*
+		 * If the rport is one of the well known addresses
+		 * we skip PRLI and RTV and go straight to READY.
+		 */
+		if (rport->port_id >= FC_FID_DOM_MGR)
+			fc_rport_enter_ready(rport);
+		else
+			fc_rport_enter_prli(rport);
+	} else
+		fc_rport_error(rport, fp);
+
+out:
+	fc_frame_free(fp);
+err:
+	mutex_unlock(&rdata->rp_mutex);
+	put_device(&rport->dev);
+}
+
+/**
+ * fc_rport_enter_plogi - Send Port Login (PLOGI) request to peer
+ * @rport: Fibre Channel remote port to send PLOGI to
+ *
+ * Locking Note: The rport lock is expected to be held before calling
+ * this routine.
+ */
+static void fc_rport_enter_plogi(struct fc_rport *rport)
+{
+	struct fc_rport_libfc_priv *rdata = rport->dd_data;
+	struct fc_lport *lport = rdata->local_port;
+	struct fc_frame *fp;
+
+	FC_DEBUG_RPORT("Port (%6x) entered PLOGI state from %s state\n",
+		       rport->port_id, fc_rport_state(rport));
+
+	fc_rport_state_enter(rport, RPORT_ST_PLOGI);
+
+	rport->maxframe_size = FC_MIN_MAX_PAYLOAD;
+	fp = fc_frame_alloc(lport, sizeof(struct fc_els_flogi));
+	if (!fp) {
+		fc_rport_error(rport, fp);
+		return;
+	}
+	rdata->e_d_tov = lport->e_d_tov;
+
+	if (!lport->tt.elsct_send(lport, rport, fp, ELS_PLOGI,
+				  fc_rport_plogi_resp, rport, lport->e_d_tov))
+		fc_rport_error(rport, fp);
+	else
+		get_device(&rport->dev);
+}
+
+/**
+ * fc_rport_prli_resp - Process Login (PRLI) response handler
+ * @sp: current sequence in the PRLI exchange
+ * @fp: response frame
+ * @rp_arg: Fibre Channel remote port
+ *
+ * Locking Note: This function will be called without the rport lock
+ * held, but it will lock, call an _enter_* function or fc_rport_error
+ * and then unlock the rport.
+ */
+static void fc_rport_prli_resp(struct fc_seq *sp, struct fc_frame *fp,
+			       void *rp_arg)
+{
+	struct fc_rport *rport = rp_arg;
+	struct fc_rport_libfc_priv *rdata = rport->dd_data;
+	struct {
+		struct fc_els_prli prli;
+		struct fc_els_spp spp;
+	} *pp;
+	u32 roles = FC_RPORT_ROLE_UNKNOWN;
+	u32 fcp_parm = 0;
+	u8 op;
+
+	mutex_lock(&rdata->rp_mutex);
+
+	FC_DEBUG_RPORT("Received a PRLI response from port (%6x)\n",
+		       rport->port_id);
+
+	if (rdata->rp_state != RPORT_ST_PRLI) {
+		FC_DBG("Received a PRLI response, but in state %s\n",
+		       fc_rport_state(rport));
+		goto out;
+	}
+
+	if (IS_ERR(fp)) {
+		fc_rport_error(rport, fp);
+		goto err;
+	}
+
+	op = fc_frame_payload_op(fp);
+	if (op == ELS_LS_ACC) {
+		pp = fc_frame_payload_get(fp, sizeof(*pp));
+		if (pp && pp->prli.prli_spp_len >= sizeof(pp->spp)) {
+			fcp_parm = ntohl(pp->spp.spp_params);
+			if (fcp_parm & FCP_SPPF_RETRY)
+				rdata->flags |= FC_RP_FLAGS_RETRY;
+		}
+
+		rport->supported_classes = FC_COS_CLASS3;
+		if (fcp_parm & FCP_SPPF_INIT_FCN)
+			roles |= FC_RPORT_ROLE_FCP_INITIATOR;
+		if (fcp_parm & FCP_SPPF_TARG_FCN)
+			roles |= FC_RPORT_ROLE_FCP_TARGET;
+
+		rport->roles = roles;
+		fc_rport_enter_rtv(rport);
+
+	} else {
+		FC_DBG("Bad ELS response\n");
+		rdata->event = RPORT_EV_FAILED;
+		queue_work(rport_event_queue, &rdata->event_work);
+	}
+
+out:
+	fc_frame_free(fp);
+err:
+	mutex_unlock(&rdata->rp_mutex);
+	put_device(&rport->dev);
+}
+
+/**
+ * fc_rport_logo_resp - Logout (LOGO) response handler
+ * @sp: current sequence in the LOGO exchange
+ * @fp: response frame
+ * @rp_arg: Fibre Channel remote port
+ *
+ * Locking Note: This function will be called without the rport lock
+ * held, but it will lock, call an _enter_* function or fc_rport_error
+ * and then unlock the rport.
+ */
+static void fc_rport_logo_resp(struct fc_seq *sp, struct fc_frame *fp,
+			       void *rp_arg)
+{
+	struct fc_rport *rport = rp_arg;
+	struct fc_rport_libfc_priv *rdata = rport->dd_data;
+	u8 op;
+
+	mutex_lock(&rdata->rp_mutex);
+
+	FC_DEBUG_RPORT("Received a LOGO response from port (%6x)\n",
+		       rport->port_id);
+
+	if (IS_ERR(fp)) {
+		fc_rport_error(rport, fp);
+		goto err;
+	}
+
+	if (rdata->rp_state != RPORT_ST_LOGO) {
+		FC_DEBUG_RPORT("Received a LOGO response, but in state %s\n",
+			       fc_rport_state(rport));
+		goto out;
+	}
+
+	op = fc_frame_payload_op(fp);
+	if (op == ELS_LS_ACC) {
+		fc_rport_enter_rtv(rport);
+	} else {
+		FC_DBG("Bad ELS response\n");
+		rdata->event = RPORT_EV_LOGO;
+		queue_work(rport_event_queue, &rdata->event_work);
+	}
+
+out:
+	fc_frame_free(fp);
+err:
+	mutex_unlock(&rdata->rp_mutex);
+	put_device(&rport->dev);
+}
+
+/**
+ * fc_rport_enter_prli - Send Process Login (PRLI) request to peer
+ * @rport: Fibre Channel remote port to send PRLI to
+ *
+ * Locking Note: The rport lock is expected to be held before calling
+ * this routine.
+ */
+static void fc_rport_enter_prli(struct fc_rport *rport)
+{
+	struct fc_rport_libfc_priv *rdata = rport->dd_data;
+	struct fc_lport *lport = rdata->local_port;
+	struct {
+		struct fc_els_prli prli;
+		struct fc_els_spp spp;
+	} *pp;
+	struct fc_frame *fp;
+
+	FC_DEBUG_RPORT("Port (%6x) entered PRLI state from %s state\n",
+		       rport->port_id, fc_rport_state(rport));
+
+	fc_rport_state_enter(rport, RPORT_ST_PRLI);
+
+	fp = fc_frame_alloc(lport, sizeof(*pp));
+	if (!fp) {
+		fc_rport_error(rport, fp);
+		return;
+	}
+
+	if (!lport->tt.elsct_send(lport, rport, fp, ELS_PRLI,
+				  fc_rport_prli_resp, rport, lport->e_d_tov))
+		fc_rport_error(rport, fp);
+	else
+		get_device(&rport->dev);
+}
+
+/**
+ * fc_rport_els_rtv_resp - Request Timeout Value response handler
+ * @sp: current sequence in the RTV exchange
+ * @fp: response frame
+ * @rp_arg: Fibre Channel remote port
+ *
+ * Many targets don't seem to support this.
+ *
+ * Locking Note: This function will be called without the rport lock
+ * held, but it will lock, call an _enter_* function or fc_rport_error
+ * and then unlock the rport.
+ */
+static void fc_rport_rtv_resp(struct fc_seq *sp, struct fc_frame *fp,
+			      void *rp_arg)
+{
+	struct fc_rport *rport = rp_arg;
+	struct fc_rport_libfc_priv *rdata = rport->dd_data;
+	u8 op;
+
+	mutex_lock(&rdata->rp_mutex);
+
+	FC_DEBUG_RPORT("Received a RTV response from port (%6x)\n",
+		       rport->port_id);
+
+	if (rdata->rp_state != RPORT_ST_RTV) {
+		FC_DBG("Received a RTV response, but in state %s\n",
+		       fc_rport_state(rport));
+		goto out;
+	}
+
+	if (IS_ERR(fp)) {
+		fc_rport_error(rport, fp);
+		goto err;
+	}
+
+	op = fc_frame_payload_op(fp);
+	if (op == ELS_LS_ACC) {
+		struct fc_els_rtv_acc *rtv;
+		u32 toq;
+		u32 tov;
+
+		rtv = fc_frame_payload_get(fp, sizeof(*rtv));
+		if (rtv) {
+			toq = ntohl(rtv->rtv_toq);
+			tov = ntohl(rtv->rtv_r_a_tov);
+			if (tov == 0)
+				tov = 1;
+			rdata->r_a_tov = tov;
+			tov = ntohl(rtv->rtv_e_d_tov);
+			if (toq & FC_ELS_RTV_EDRES)
+				tov /= 1000000;
+			if (tov == 0)
+				tov = 1;
+			rdata->e_d_tov = tov;
+		}
+	}
+
+	fc_rport_enter_ready(rport);
+
+out:
+	fc_frame_free(fp);
+err:
+	mutex_unlock(&rdata->rp_mutex);
+	put_device(&rport->dev);
+}
+
+/**
+ * fc_rport_enter_rtv - Send Request Timeout Value (RTV) request to peer
+ * @rport: Fibre Channel remote port to send RTV to
+ *
+ * Locking Note: The rport lock is expected to be held before calling
+ * this routine.
+ */
+static void fc_rport_enter_rtv(struct fc_rport *rport)
+{
+	struct fc_frame *fp;
+	struct fc_rport_libfc_priv *rdata = rport->dd_data;
+	struct fc_lport *lport = rdata->local_port;
+
+	FC_DEBUG_RPORT("Port (%6x) entered RTV state from %s state\n",
+		       rport->port_id, fc_rport_state(rport));
+
+	fc_rport_state_enter(rport, RPORT_ST_RTV);
+
+	fp = fc_frame_alloc(lport, sizeof(struct fc_els_rtv));
+	if (!fp) {
+		fc_rport_error(rport, fp);
+		return;
+	}
+
+	if (!lport->tt.elsct_send(lport, rport, fp, ELS_RTV,
+				     fc_rport_rtv_resp, rport, lport->e_d_tov))
+		fc_rport_error(rport, fp);
+	else
+		get_device(&rport->dev);
+}
+
+/**
+ * fc_rport_enter_logo - Send Logout (LOGO) request to peer
+ * @rport: Fibre Channel remote port to send LOGO to
+ *
+ * Locking Note: The rport lock is expected to be held before calling
+ * this routine.
+ */
+static void fc_rport_enter_logo(struct fc_rport *rport)
+{
+	struct fc_rport_libfc_priv *rdata = rport->dd_data;
+	struct fc_lport *lport = rdata->local_port;
+	struct fc_frame *fp;
+
+	FC_DEBUG_RPORT("Port (%6x) entered LOGO state from %s state\n",
+		       rport->port_id, fc_rport_state(rport));
+
+	fc_rport_state_enter(rport, RPORT_ST_LOGO);
+
+	fp = fc_frame_alloc(lport, sizeof(struct fc_els_logo));
+	if (!fp) {
+		fc_rport_error(rport, fp);
+		return;
+	}
+
+	if (!lport->tt.elsct_send(lport, rport, fp, ELS_LOGO,
+				  fc_rport_logo_resp, rport, lport->e_d_tov))
+		fc_rport_error(rport, fp);
+	else
+		get_device(&rport->dev);
+}
+
+
+/**
+ * fc_rport_recv_req - Receive a request from a rport
+ * @sp: current sequence in the PLOGI exchange
+ * @fp: response frame
+ * @rp_arg: Fibre Channel remote port
+ *
+ * Locking Note: Called without the rport lock held. This
+ * function will hold the rport lock, call an _enter_*
+ * function and then unlock the rport.
+ */
+void fc_rport_recv_req(struct fc_seq *sp, struct fc_frame *fp,
+		       struct fc_rport *rport)
+{
+	struct fc_rport_libfc_priv *rdata = rport->dd_data;
+	struct fc_lport *lport = rdata->local_port;
+
+	struct fc_frame_header *fh;
+	struct fc_seq_els_data els_data;
+	u8 op;
+
+	mutex_lock(&rdata->rp_mutex);
+
+	els_data.fp = NULL;
+	els_data.explan = ELS_EXPL_NONE;
+	els_data.reason = ELS_RJT_NONE;
+
+	fh = fc_frame_header_get(fp);
+
+	if (fh->fh_r_ctl == FC_RCTL_ELS_REQ && fh->fh_type == FC_TYPE_ELS) {
+		op = fc_frame_payload_op(fp);
+		switch (op) {
+		case ELS_PLOGI:
+			fc_rport_recv_plogi_req(rport, sp, fp);
+			break;
+		case ELS_PRLI:
+			fc_rport_recv_prli_req(rport, sp, fp);
+			break;
+		case ELS_PRLO:
+			fc_rport_recv_prlo_req(rport, sp, fp);
+			break;
+		case ELS_LOGO:
+			fc_rport_recv_logo_req(rport, sp, fp);
+			break;
+		case ELS_RRQ:
+			els_data.fp = fp;
+			lport->tt.seq_els_rsp_send(sp, ELS_RRQ, &els_data);
+			break;
+		case ELS_REC:
+			els_data.fp = fp;
+			lport->tt.seq_els_rsp_send(sp, ELS_REC, &els_data);
+			break;
+		default:
+			els_data.reason = ELS_RJT_UNSUP;
+			lport->tt.seq_els_rsp_send(sp, ELS_LS_RJT, &els_data);
+			break;
+		}
+	}
+
+	mutex_unlock(&rdata->rp_mutex);
+}
+
+/**
+ * fc_rport_recv_plogi_req - Handle incoming Port Login (PLOGI) request
+ * @rport: Fibre Channel remote port that initiated PLOGI
+ * @sp: current sequence in the PLOGI exchange
+ * @fp: PLOGI request frame
+ *
+ * Locking Note: The rport lock is exected to be held before calling
+ * this function.
+ */
+static void fc_rport_recv_plogi_req(struct fc_rport *rport,
+				    struct fc_seq *sp, struct fc_frame *rx_fp)
+{
+	struct fc_rport_libfc_priv *rdata = rport->dd_data;
+	struct fc_lport *lport = rdata->local_port;
+	struct fc_frame *fp = rx_fp;
+	struct fc_exch *ep;
+	struct fc_frame_header *fh;
+	struct fc_els_flogi *pl;
+	struct fc_seq_els_data rjt_data;
+	u32 sid;
+	u64 wwpn;
+	u64 wwnn;
+	enum fc_els_rjt_reason reject = 0;
+	u32 f_ctl;
+	rjt_data.fp = NULL;
+
+	fh = fc_frame_header_get(fp);
+
+	FC_DEBUG_RPORT("Received PLOGI request from port (%6x) "
+		       "while in state %s\n", ntoh24(fh->fh_s_id),
+		       fc_rport_state(rport));
+
+	sid = ntoh24(fh->fh_s_id);
+	pl = fc_frame_payload_get(fp, sizeof(*pl));
+	if (!pl) {
+		FC_DBG("incoming PLOGI from %x too short\n", sid);
+		WARN_ON(1);
+		/* XXX TBD: send reject? */
+		fc_frame_free(fp);
+		return;
+	}
+	wwpn = get_unaligned_be64(&pl->fl_wwpn);
+	wwnn = get_unaligned_be64(&pl->fl_wwnn);
+
+	/*
+	 * If the session was just created, possibly due to the incoming PLOGI,
+	 * set the state appropriately and accept the PLOGI.
+	 *
+	 * If we had also sent a PLOGI, and if the received PLOGI is from a
+	 * higher WWPN, we accept it, otherwise an LS_RJT is sent with reason
+	 * "command already in progress".
+	 *
+	 * XXX TBD: If the session was ready before, the PLOGI should result in
+	 * all outstanding exchanges being reset.
+	 */
+	switch (rdata->rp_state) {
+	case RPORT_ST_INIT:
+		FC_DEBUG_RPORT("incoming PLOGI from %6x wwpn %llx state INIT "
+			       "- reject\n", sid, wwpn);
+		reject = ELS_RJT_UNSUP;
+		break;
+	case RPORT_ST_PLOGI:
+		FC_DEBUG_RPORT("incoming PLOGI from %x in PLOGI state %d\n",
+			       sid, rdata->rp_state);
+		if (wwpn < lport->wwpn)
+			reject = ELS_RJT_INPROG;
+		break;
+	case RPORT_ST_PRLI:
+	case RPORT_ST_READY:
+		FC_DEBUG_RPORT("incoming PLOGI from %x in logged-in state %d "
+			       "- ignored for now\n", sid, rdata->rp_state);
+		/* XXX TBD - should reset */
+		break;
+	case RPORT_ST_NONE:
+	default:
+		FC_DEBUG_RPORT("incoming PLOGI from %x in unexpected "
+			       "state %d\n", sid, rdata->rp_state);
+		break;
+	}
+
+	if (reject) {
+		rjt_data.reason = reject;
+		rjt_data.explan = ELS_EXPL_NONE;
+		lport->tt.seq_els_rsp_send(sp, ELS_LS_RJT, &rjt_data);
+		fc_frame_free(fp);
+	} else {
+		fp = fc_frame_alloc(lport, sizeof(*pl));
+		if (fp == NULL) {
+			fp = rx_fp;
+			rjt_data.reason = ELS_RJT_UNAB;
+			rjt_data.explan = ELS_EXPL_NONE;
+			lport->tt.seq_els_rsp_send(sp, ELS_LS_RJT, &rjt_data);
+			fc_frame_free(fp);
+		} else {
+			sp = lport->tt.seq_start_next(sp);
+			WARN_ON(!sp);
+			fc_rport_set_name(rport, wwpn, wwnn);
+
+			/*
+			 * Get session payload size from incoming PLOGI.
+			 */
+			rport->maxframe_size =
+				fc_plogi_get_maxframe(pl, lport->mfs);
+			fc_frame_free(rx_fp);
+			fc_plogi_fill(lport, fp, ELS_LS_ACC);
+
+			/*
+			 * Send LS_ACC.	 If this fails,
+			 * the originator should retry.
+			 */
+			f_ctl = FC_FC_EX_CTX | FC_FC_LAST_SEQ;
+			f_ctl |= FC_FC_END_SEQ | FC_FC_SEQ_INIT;
+			ep = fc_seq_exch(sp);
+			fc_fill_fc_hdr(fp, FC_RCTL_ELS_REP, ep->did, ep->sid,
+				       FC_TYPE_ELS, f_ctl, 0);
+			lport->tt.seq_send(lport, sp, fp);
+			if (rdata->rp_state == RPORT_ST_PLOGI)
+				fc_rport_enter_prli(rport);
+		}
+	}
+}
+
+/**
+ * fc_rport_recv_prli_req - Handle incoming Process Login (PRLI) request
+ * @rport: Fibre Channel remote port that initiated PRLI
+ * @sp: current sequence in the PRLI exchange
+ * @fp: PRLI request frame
+ *
+ * Locking Note: The rport lock is exected to be held before calling
+ * this function.
+ */
+static void fc_rport_recv_prli_req(struct fc_rport *rport,
+				   struct fc_seq *sp, struct fc_frame *rx_fp)
+{
+	struct fc_rport_libfc_priv *rdata = rport->dd_data;
+	struct fc_lport *lport = rdata->local_port;
+	struct fc_exch *ep;
+	struct fc_frame *fp;
+	struct fc_frame_header *fh;
+	struct {
+		struct fc_els_prli prli;
+		struct fc_els_spp spp;
+	} *pp;
+	struct fc_els_spp *rspp;	/* request service param page */
+	struct fc_els_spp *spp;	/* response spp */
+	unsigned int len;
+	unsigned int plen;
+	enum fc_els_rjt_reason reason = ELS_RJT_UNAB;
+	enum fc_els_rjt_explan explan = ELS_EXPL_NONE;
+	enum fc_els_spp_resp resp;
+	struct fc_seq_els_data rjt_data;
+	u32 f_ctl;
+	u32 fcp_parm;
+	u32 roles = FC_RPORT_ROLE_UNKNOWN;
+	rjt_data.fp = NULL;
+
+	fh = fc_frame_header_get(rx_fp);
+
+	FC_DEBUG_RPORT("Received PRLI request from port (%6x) "
+		       "while in state %s\n", ntoh24(fh->fh_s_id),
+		       fc_rport_state(rport));
+
+	switch (rdata->rp_state) {
+	case RPORT_ST_PRLI:
+	case RPORT_ST_READY:
+		reason = ELS_RJT_NONE;
+		break;
+	default:
+		break;
+	}
+	len = fr_len(rx_fp) - sizeof(*fh);
+	pp = fc_frame_payload_get(rx_fp, sizeof(*pp));
+	if (pp == NULL) {
+		reason = ELS_RJT_PROT;
+		explan = ELS_EXPL_INV_LEN;
+	} else {
+		plen = ntohs(pp->prli.prli_len);
+		if ((plen % 4) != 0 || plen > len) {
+			reason = ELS_RJT_PROT;
+			explan = ELS_EXPL_INV_LEN;
+		} else if (plen < len) {
+			len = plen;
+		}
+		plen = pp->prli.prli_spp_len;
+		if ((plen % 4) != 0 || plen < sizeof(*spp) ||
+		    plen > len || len < sizeof(*pp)) {
+			reason = ELS_RJT_PROT;
+			explan = ELS_EXPL_INV_LEN;
+		}
+		rspp = &pp->spp;
+	}
+	if (reason != ELS_RJT_NONE ||
+	    (fp = fc_frame_alloc(lport, len)) == NULL) {
+		rjt_data.reason = reason;
+		rjt_data.explan = explan;
+		lport->tt.seq_els_rsp_send(sp, ELS_LS_RJT, &rjt_data);
+	} else {
+		sp = lport->tt.seq_start_next(sp);
+		WARN_ON(!sp);
+		pp = fc_frame_payload_get(fp, len);
+		WARN_ON(!pp);
+		memset(pp, 0, len);
+		pp->prli.prli_cmd = ELS_LS_ACC;
+		pp->prli.prli_spp_len = plen;
+		pp->prli.prli_len = htons(len);
+		len -= sizeof(struct fc_els_prli);
+
+		/*
+		 * Go through all the service parameter pages and build
+		 * response.  If plen indicates longer SPP than standard,
+		 * use that.  The entire response has been pre-cleared above.
+		 */
+		spp = &pp->spp;
+		while (len >= plen) {
+			spp->spp_type = rspp->spp_type;
+			spp->spp_type_ext = rspp->spp_type_ext;
+			spp->spp_flags = rspp->spp_flags & FC_SPP_EST_IMG_PAIR;
+			resp = FC_SPP_RESP_ACK;
+			if (rspp->spp_flags & FC_SPP_RPA_VAL)
+				resp = FC_SPP_RESP_NO_PA;
+			switch (rspp->spp_type) {
+			case 0:	/* common to all FC-4 types */
+				break;
+			case FC_TYPE_FCP:
+				fcp_parm = ntohl(rspp->spp_params);
+				if (fcp_parm * FCP_SPPF_RETRY)
+					rdata->flags |= FC_RP_FLAGS_RETRY;
+				rport->supported_classes = FC_COS_CLASS3;
+				if (fcp_parm & FCP_SPPF_INIT_FCN)
+					roles |= FC_RPORT_ROLE_FCP_INITIATOR;
+				if (fcp_parm & FCP_SPPF_TARG_FCN)
+					roles |= FC_RPORT_ROLE_FCP_TARGET;
+				rport->roles = roles;
+
+				spp->spp_params =
+					htonl(lport->service_params);
+				break;
+			default:
+				resp = FC_SPP_RESP_INVL;
+				break;
+			}
+			spp->spp_flags |= resp;
+			len -= plen;
+			rspp = (struct fc_els_spp *)((char *)rspp + plen);
+			spp = (struct fc_els_spp *)((char *)spp + plen);
+		}
+
+		/*
+		 * Send LS_ACC.	 If this fails, the originator should retry.
+		 */
+		f_ctl = FC_FC_EX_CTX | FC_FC_LAST_SEQ;
+		f_ctl |= FC_FC_END_SEQ | FC_FC_SEQ_INIT;
+		ep = fc_seq_exch(sp);
+		fc_fill_fc_hdr(fp, FC_RCTL_ELS_REP, ep->did, ep->sid,
+			       FC_TYPE_ELS, f_ctl, 0);
+		lport->tt.seq_send(lport, sp, fp);
+
+		/*
+		 * Get lock and re-check state.
+		 */
+		switch (rdata->rp_state) {
+		case RPORT_ST_PRLI:
+			fc_rport_enter_ready(rport);
+			break;
+		case RPORT_ST_READY:
+			break;
+		default:
+			break;
+		}
+	}
+	fc_frame_free(rx_fp);
+}
+
+/**
+ * fc_rport_recv_prlo_req - Handle incoming Process Logout (PRLO) request
+ * @rport: Fibre Channel remote port that initiated PRLO
+ * @sp: current sequence in the PRLO exchange
+ * @fp: PRLO request frame
+ *
+ * Locking Note: The rport lock is exected to be held before calling
+ * this function.
+ */
+static void fc_rport_recv_prlo_req(struct fc_rport *rport, struct fc_seq *sp,
+				   struct fc_frame *fp)
+{
+	struct fc_rport_libfc_priv *rdata = rport->dd_data;
+	struct fc_lport *lport = rdata->local_port;
+
+	struct fc_frame_header *fh;
+	struct fc_seq_els_data rjt_data;
+
+	fh = fc_frame_header_get(fp);
+
+	FC_DEBUG_RPORT("Received PRLO request from port (%6x) "
+		       "while in state %s\n", ntoh24(fh->fh_s_id),
+		       fc_rport_state(rport));
+
+	rjt_data.fp = NULL;
+	rjt_data.reason = ELS_RJT_UNAB;
+	rjt_data.explan = ELS_EXPL_NONE;
+	lport->tt.seq_els_rsp_send(sp, ELS_LS_RJT, &rjt_data);
+	fc_frame_free(fp);
+}
+
+/**
+ * fc_rport_recv_logo_req - Handle incoming Logout (LOGO) request
+ * @rport: Fibre Channel remote port that initiated LOGO
+ * @sp: current sequence in the LOGO exchange
+ * @fp: LOGO request frame
+ *
+ * Locking Note: The rport lock is exected to be held before calling
+ * this function.
+ */
+static void fc_rport_recv_logo_req(struct fc_rport *rport, struct fc_seq *sp,
+				   struct fc_frame *fp)
+{
+	struct fc_frame_header *fh;
+	struct fc_rport_libfc_priv *rdata = rport->dd_data;
+	struct fc_lport *lport = rdata->local_port;
+
+	fh = fc_frame_header_get(fp);
+
+	FC_DEBUG_RPORT("Received LOGO request from port (%6x) "
+		       "while in state %s\n", ntoh24(fh->fh_s_id),
+		       fc_rport_state(rport));
+
+	rdata->event = RPORT_EV_LOGO;
+	queue_work(rport_event_queue, &rdata->event_work);
+
+	lport->tt.seq_els_rsp_send(sp, ELS_LS_ACC, NULL);
+	fc_frame_free(fp);
+}
+
+static void fc_rport_flush_queue(void)
+{
+	flush_workqueue(rport_event_queue);
+}
+
+
+int fc_rport_init(struct fc_lport *lport)
+{
+	if (!lport->tt.rport_login)
+		lport->tt.rport_login = fc_rport_login;
+
+	if (!lport->tt.rport_logoff)
+		lport->tt.rport_logoff = fc_rport_logoff;
+
+	if (!lport->tt.rport_recv_req)
+		lport->tt.rport_recv_req = fc_rport_recv_req;
+
+	if (!lport->tt.rport_flush_queue)
+		lport->tt.rport_flush_queue = fc_rport_flush_queue;
+
+	return 0;
+}
+EXPORT_SYMBOL(fc_rport_init);
+
+int fc_setup_rport()
+{
+	rport_event_queue = create_singlethread_workqueue("fc_rport_eq");
+	if (!rport_event_queue)
+		return -ENOMEM;
+	return 0;
+}
+EXPORT_SYMBOL(fc_setup_rport);
+
+void fc_destroy_rport()
+{
+	destroy_workqueue(rport_event_queue);
+}
+EXPORT_SYMBOL(fc_destroy_rport);
+
+void fc_rport_terminate_io(struct fc_rport *rport)
+{
+	struct fc_rport_libfc_priv *rdata = rport->dd_data;
+	struct fc_lport *lport = rdata->local_port;
+
+	lport->tt.exch_mgr_reset(lport->emp, 0, rport->port_id);
+	lport->tt.exch_mgr_reset(lport->emp, rport->port_id, 0);
+}
+EXPORT_SYMBOL(fc_rport_terminate_io);

include/scsi/fc_encode.h

···
+/*
+ * Copyright(c) 2008 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Maintained at www.Open-FCoE.org
+ */
+
+#ifndef _FC_ENCODE_H_
+#define _FC_ENCODE_H_
+#include <asm/unaligned.h>
+
+struct fc_ns_rft {
+	struct fc_ns_fid fid;	/* port ID object */
+	struct fc_ns_fts fts;	/* FC4-types object */
+};
+
+struct fc_ct_req {
+	struct fc_ct_hdr hdr;
+	union {
+		struct fc_ns_gid_ft gid;
+		struct fc_ns_rn_id  rn;
+		struct fc_ns_rft rft;
+	} payload;
+};
+
+/**
+ * fill FC header fields in specified fc_frame
+ */
+static inline void fc_fill_fc_hdr(struct fc_frame *fp, enum fc_rctl r_ctl,
+				  u32 did, u32 sid, enum fc_fh_type type,
+				  u32 f_ctl, u32 parm_offset)
+{
+	struct fc_frame_header *fh;
+
+	fh = fc_frame_header_get(fp);
+	WARN_ON(r_ctl == 0);
+	fh->fh_r_ctl = r_ctl;
+	hton24(fh->fh_d_id, did);
+	hton24(fh->fh_s_id, sid);
+	fh->fh_type = type;
+	hton24(fh->fh_f_ctl, f_ctl);
+	fh->fh_cs_ctl = 0;
+	fh->fh_df_ctl = 0;
+	fh->fh_parm_offset = htonl(parm_offset);
+}
+
+/**
+ * fc_ct_hdr_fill- fills ct header and reset ct payload
+ * returns pointer to ct request.
+ */
+static inline struct fc_ct_req *fc_ct_hdr_fill(const struct fc_frame *fp,
+					       unsigned int op, size_t req_size)
+{
+	struct fc_ct_req *ct;
+	size_t ct_plen;
+
+	ct_plen  = sizeof(struct fc_ct_hdr) + req_size;
+	ct = fc_frame_payload_get(fp, ct_plen);
+	memset(ct, 0, ct_plen);
+	ct->hdr.ct_rev = FC_CT_REV;
+	ct->hdr.ct_fs_type = FC_FST_DIR;
+	ct->hdr.ct_fs_subtype = FC_NS_SUBTYPE;
+	ct->hdr.ct_cmd = htons((u16) op);
+	return ct;
+}
+
+/**
+ * fc_ct_fill - Fill in a name service request frame
+ */
+static inline int fc_ct_fill(struct fc_lport *lport, struct fc_frame *fp,
+		      unsigned int op, enum fc_rctl *r_ctl, u32 *did,
+		      enum fc_fh_type *fh_type)
+{
+	struct fc_ct_req *ct;
+
+	switch (op) {
+	case FC_NS_GPN_FT:
+		ct = fc_ct_hdr_fill(fp, op, sizeof(struct fc_ns_gid_ft));
+		ct->payload.gid.fn_fc4_type = FC_TYPE_FCP;
+		break;
+
+	case FC_NS_RFT_ID:
+		ct = fc_ct_hdr_fill(fp, op, sizeof(struct fc_ns_rft));
+		hton24(ct->payload.rft.fid.fp_fid,
+		       fc_host_port_id(lport->host));
+		ct->payload.rft.fts = lport->fcts;
+		break;
+
+	case FC_NS_RPN_ID:
+		ct = fc_ct_hdr_fill(fp, op, sizeof(struct fc_ns_rn_id));
+		hton24(ct->payload.rn.fr_fid.fp_fid,
+		       fc_host_port_id(lport->host));
+		ct->payload.rft.fts = lport->fcts;
+		put_unaligned_be64(lport->wwpn, &ct->payload.rn.fr_wwn);
+		break;
+
+	default:
+		FC_DBG("Invalid op code %x \n", op);
+		return -EINVAL;
+	}
+	*r_ctl = FC_RCTL_DD_UNSOL_CTL;
+	*did = FC_FID_DIR_SERV;
+	*fh_type = FC_TYPE_CT;
+	return 0;
+}
+
+/**
+ * fc_plogi_fill - Fill in plogi request frame
+ */
+static inline void fc_plogi_fill(struct fc_lport *lport, struct fc_frame *fp,
+				 unsigned int op)
+{
+	struct fc_els_flogi *plogi;
+	struct fc_els_csp *csp;
+	struct fc_els_cssp *cp;
+
+	plogi = fc_frame_payload_get(fp, sizeof(*plogi));
+	memset(plogi, 0, sizeof(*plogi));
+	plogi->fl_cmd = (u8) op;
+	put_unaligned_be64(lport->wwpn, &plogi->fl_wwpn);
+	put_unaligned_be64(lport->wwnn, &plogi->fl_wwnn);
+
+	csp = &plogi->fl_csp;
+	csp->sp_hi_ver = 0x20;
+	csp->sp_lo_ver = 0x20;
+	csp->sp_bb_cred = htons(10);	/* this gets set by gateway */
+	csp->sp_bb_data = htons((u16) lport->mfs);
+	cp = &plogi->fl_cssp[3 - 1];	/* class 3 parameters */
+	cp->cp_class = htons(FC_CPC_VALID | FC_CPC_SEQ);
+	csp->sp_features = htons(FC_SP_FT_CIRO);
+	csp->sp_tot_seq = htons(255);	/* seq. we accept */
+	csp->sp_rel_off = htons(0x1f);
+	csp->sp_e_d_tov = htonl(lport->e_d_tov);
+
+	cp->cp_rdfs = htons((u16) lport->mfs);
+	cp->cp_con_seq = htons(255);
+	cp->cp_open_seq = 1;
+}
+
+/**
+ * fc_flogi_fill - Fill in a flogi request frame.
+ */
+static inline void fc_flogi_fill(struct fc_lport *lport, struct fc_frame *fp)
+{
+	struct fc_els_csp *sp;
+	struct fc_els_cssp *cp;
+	struct fc_els_flogi *flogi;
+
+	flogi = fc_frame_payload_get(fp, sizeof(*flogi));
+	memset(flogi, 0, sizeof(*flogi));
+	flogi->fl_cmd = (u8) ELS_FLOGI;
+	put_unaligned_be64(lport->wwpn, &flogi->fl_wwpn);
+	put_unaligned_be64(lport->wwnn, &flogi->fl_wwnn);
+	sp = &flogi->fl_csp;
+	sp->sp_hi_ver = 0x20;
+	sp->sp_lo_ver = 0x20;
+	sp->sp_bb_cred = htons(10);	/* this gets set by gateway */
+	sp->sp_bb_data = htons((u16) lport->mfs);
+	cp = &flogi->fl_cssp[3 - 1];	/* class 3 parameters */
+	cp->cp_class = htons(FC_CPC_VALID | FC_CPC_SEQ);
+}
+
+/**
+ * fc_logo_fill - Fill in a logo request frame.
+ */
+static inline void fc_logo_fill(struct fc_lport *lport, struct fc_frame *fp)
+{
+	struct fc_els_logo *logo;
+
+	logo = fc_frame_payload_get(fp, sizeof(*logo));
+	memset(logo, 0, sizeof(*logo));
+	logo->fl_cmd = ELS_LOGO;
+	hton24(logo->fl_n_port_id, fc_host_port_id(lport->host));
+	logo->fl_n_port_wwn = htonll(lport->wwpn);
+}
+
+/**
+ * fc_rtv_fill - Fill in RTV (read timeout value) request frame.
+ */
+static inline void fc_rtv_fill(struct fc_lport *lport, struct fc_frame *fp)
+{
+	struct fc_els_rtv *rtv;
+
+	rtv = fc_frame_payload_get(fp, sizeof(*rtv));
+	memset(rtv, 0, sizeof(*rtv));
+	rtv->rtv_cmd = ELS_RTV;
+}
+
+/**
+ * fc_rec_fill - Fill in rec request frame
+ */
+static inline void fc_rec_fill(struct fc_lport *lport, struct fc_frame *fp)
+{
+	struct fc_els_rec *rec;
+	struct fc_exch *ep = fc_seq_exch(fr_seq(fp));
+
+	rec = fc_frame_payload_get(fp, sizeof(*rec));
+	memset(rec, 0, sizeof(*rec));
+	rec->rec_cmd = ELS_REC;
+	hton24(rec->rec_s_id, fc_host_port_id(lport->host));
+	rec->rec_ox_id = htons(ep->oxid);
+	rec->rec_rx_id = htons(ep->rxid);
+}
+
+/**
+ * fc_prli_fill - Fill in prli request frame
+ */
+static inline void fc_prli_fill(struct fc_lport *lport, struct fc_frame *fp)
+{
+	struct {
+		struct fc_els_prli prli;
+		struct fc_els_spp spp;
+	} *pp;
+
+	pp = fc_frame_payload_get(fp, sizeof(*pp));
+	memset(pp, 0, sizeof(*pp));
+	pp->prli.prli_cmd = ELS_PRLI;
+	pp->prli.prli_spp_len = sizeof(struct fc_els_spp);
+	pp->prli.prli_len = htons(sizeof(*pp));
+	pp->spp.spp_type = FC_TYPE_FCP;
+	pp->spp.spp_flags = FC_SPP_EST_IMG_PAIR;
+	pp->spp.spp_params = htonl(lport->service_params);
+}
+
+/**
+ * fc_scr_fill - Fill in a scr request frame.
+ */
+static inline void fc_scr_fill(struct fc_lport *lport, struct fc_frame *fp)
+{
+	struct fc_els_scr *scr;
+
+	scr = fc_frame_payload_get(fp, sizeof(*scr));
+	memset(scr, 0, sizeof(*scr));
+	scr->scr_cmd = ELS_SCR;
+	scr->scr_reg_func = ELS_SCRF_FULL;
+}
+
+/**
+ * fc_els_fill - Fill in an ELS  request frame
+ */
+static inline int fc_els_fill(struct fc_lport *lport, struct fc_rport *rport,
+		       struct fc_frame *fp, unsigned int op,
+		       enum fc_rctl *r_ctl, u32 *did, enum fc_fh_type *fh_type)
+{
+	switch (op) {
+	case ELS_PLOGI:
+		fc_plogi_fill(lport, fp, ELS_PLOGI);
+		*did = rport->port_id;
+		break;
+
+	case ELS_FLOGI:
+		fc_flogi_fill(lport, fp);
+		*did = FC_FID_FLOGI;
+		break;
+
+	case ELS_LOGO:
+		fc_logo_fill(lport, fp);
+		*did = FC_FID_FLOGI;
+		/*
+		 * if rport is valid then it
+		 * is port logo, therefore
+		 * set did to rport id.
+		 */
+		if (rport)
+			*did = rport->port_id;
+		break;
+
+	case ELS_RTV:
+		fc_rtv_fill(lport, fp);
+		*did = rport->port_id;
+		break;
+
+	case ELS_REC:
+		fc_rec_fill(lport, fp);
+		*did = rport->port_id;
+		break;
+
+	case ELS_PRLI:
+		fc_prli_fill(lport, fp);
+		*did = rport->port_id;
+		break;
+
+	case ELS_SCR:
+		fc_scr_fill(lport, fp);
+		*did = FC_FID_FCTRL;
+		break;
+
+	default:
+		FC_DBG("Invalid op code %x \n", op);
+		return -EINVAL;
+	}
+
+	*r_ctl = FC_RCTL_ELS_REQ;
+	*fh_type = FC_TYPE_ELS;
+	return 0;
+}
+#endif /* _FC_ENCODE_H_ */

include/scsi/fc_frame.h

···
+/*
+ * Copyright(c) 2007 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Maintained at www.Open-FCoE.org
+ */
+
+#ifndef _FC_FRAME_H_
+#define _FC_FRAME_H_
+
+#include <linux/scatterlist.h>
+#include <linux/skbuff.h>
+#include <scsi/scsi_cmnd.h>
+
+#include <scsi/fc/fc_fs.h>
+#include <scsi/fc/fc_fcp.h>
+#include <scsi/fc/fc_encaps.h>
+
+/*
+ * The fc_frame interface is used to pass frame data between functions.
+ * The frame includes the data buffer, length, and SOF / EOF delimiter types.
+ * A pointer to the port structure of the receiving port is also includeded.
+ */
+
+#define	FC_FRAME_HEADROOM	32	/* headroom for VLAN + FCoE headers */
+#define	FC_FRAME_TAILROOM	8	/* trailer space for FCoE */
+
+/*
+ * Information about an individual fibre channel frame received or to be sent.
+ * The buffer may be in up to 4 additional non-contiguous sections,
+ * but the linear section must hold the frame header.
+ */
+#define FC_FRAME_SG_LEN		4	/* scatter/gather list maximum length */
+
+#define fp_skb(fp)	(&((fp)->skb))
+#define fr_hdr(fp)	((fp)->skb.data)
+#define fr_len(fp)	((fp)->skb.len)
+#define fr_cb(fp)	((struct fcoe_rcv_info *)&((fp)->skb.cb[0]))
+#define fr_dev(fp)	(fr_cb(fp)->fr_dev)
+#define fr_seq(fp)	(fr_cb(fp)->fr_seq)
+#define fr_sof(fp)	(fr_cb(fp)->fr_sof)
+#define fr_eof(fp)	(fr_cb(fp)->fr_eof)
+#define fr_flags(fp)	(fr_cb(fp)->fr_flags)
+#define fr_max_payload(fp)	(fr_cb(fp)->fr_max_payload)
+#define fr_cmd(fp)	(fr_cb(fp)->fr_cmd)
+#define fr_dir(fp)	(fr_cmd(fp)->sc_data_direction)
+#define fr_crc(fp)	(fr_cb(fp)->fr_crc)
+
+struct fc_frame {
+	struct sk_buff skb;
+};
+
+struct fcoe_rcv_info {
+	struct packet_type  *ptype;
+	struct fc_lport	*fr_dev;	/* transport layer private pointer */
+	struct fc_seq	*fr_seq;	/* for use with exchange manager */
+	struct scsi_cmnd *fr_cmd;	/* for use of scsi command */
+	u32		fr_crc;
+	u16		fr_max_payload;	/* max FC payload */
+	enum fc_sof	fr_sof;		/* start of frame delimiter */
+	enum fc_eof	fr_eof;		/* end of frame delimiter */
+	u8		fr_flags;	/* flags - see below */
+};
+
+
+/*
+ * Get fc_frame pointer for an skb that's already been imported.
+ */
+static inline struct fcoe_rcv_info *fcoe_dev_from_skb(const struct sk_buff *skb)
+{
+	BUILD_BUG_ON(sizeof(struct fcoe_rcv_info) > sizeof(skb->cb));
+	return (struct fcoe_rcv_info *) skb->cb;
+}
+
+/*
+ * fr_flags.
+ */
+#define	FCPHF_CRC_UNCHECKED	0x01	/* CRC not computed, still appended */
+
+/*
+ * Initialize a frame.
+ * We don't do a complete memset here for performance reasons.
+ * The caller must set fr_free, fr_hdr, fr_len, fr_sof, and fr_eof eventually.
+ */
+static inline void fc_frame_init(struct fc_frame *fp)
+{
+	fr_dev(fp) = NULL;
+	fr_seq(fp) = NULL;
+	fr_flags(fp) = 0;
+}
+
+struct fc_frame *fc_frame_alloc_fill(struct fc_lport *, size_t payload_len);
+
+struct fc_frame *__fc_frame_alloc(size_t payload_len);
+
+/*
+ * Get frame for sending via port.
+ */
+static inline struct fc_frame *_fc_frame_alloc(struct fc_lport *dev,
+					       size_t payload_len)
+{
+	return __fc_frame_alloc(payload_len);
+}
+
+/*
+ * Allocate fc_frame structure and buffer.  Set the initial length to
+ * payload_size + sizeof (struct fc_frame_header).
+ */
+static inline struct fc_frame *fc_frame_alloc(struct fc_lport *dev, size_t len)
+{
+	struct fc_frame *fp;
+
+	/*
+	 * Note: Since len will often be a constant multiple of 4,
+	 * this check will usually be evaluated and eliminated at compile time.
+	 */
+	if ((len % 4) != 0)
+		fp = fc_frame_alloc_fill(dev, len);
+	else
+		fp = _fc_frame_alloc(dev, len);
+	return fp;
+}
+
+/*
+ * Free the fc_frame structure and buffer.
+ */
+static inline void fc_frame_free(struct fc_frame *fp)
+{
+	kfree_skb(fp_skb(fp));
+}
+
+static inline int fc_frame_is_linear(struct fc_frame *fp)
+{
+	return !skb_is_nonlinear(fp_skb(fp));
+}
+
+/*
+ * Get frame header from message in fc_frame structure.
+ * This hides a cast and provides a place to add some checking.
+ */
+static inline
+struct fc_frame_header *fc_frame_header_get(const struct fc_frame *fp)
+{
+	WARN_ON(fr_len(fp) < sizeof(struct fc_frame_header));
+	return (struct fc_frame_header *) fr_hdr(fp);
+}
+
+/*
+ * Get frame payload from message in fc_frame structure.
+ * This hides a cast and provides a place to add some checking.
+ * The len parameter is the minimum length for the payload portion.
+ * Returns NULL if the frame is too short.
+ *
+ * This assumes the interesting part of the payload is in the first part
+ * of the buffer for received data.  This may not be appropriate to use for
+ * buffers being transmitted.
+ */
+static inline void *fc_frame_payload_get(const struct fc_frame *fp,
+					 size_t len)
+{
+	void *pp = NULL;
+
+	if (fr_len(fp) >= sizeof(struct fc_frame_header) + len)
+		pp = fc_frame_header_get(fp) + 1;
+	return pp;
+}
+
+/*
+ * Get frame payload opcode (first byte) from message in fc_frame structure.
+ * This hides a cast and provides a place to add some checking. Return 0
+ * if the frame has no payload.
+ */
+static inline u8 fc_frame_payload_op(const struct fc_frame *fp)
+{
+	u8 *cp;
+
+	cp = fc_frame_payload_get(fp, sizeof(u8));
+	if (!cp)
+		return 0;
+	return *cp;
+
+}
+
+/*
+ * Get FC class from frame.
+ */
+static inline enum fc_class fc_frame_class(const struct fc_frame *fp)
+{
+	return fc_sof_class(fr_sof(fp));
+}
+
+/*
+ * Check the CRC in a frame.
+ * The CRC immediately follows the last data item *AFTER* the length.
+ * The return value is zero if the CRC matches.
+ */
+u32 fc_frame_crc_check(struct fc_frame *);
+
+static inline u8 fc_frame_rctl(const struct fc_frame *fp)
+{
+	return fc_frame_header_get(fp)->fh_r_ctl;
+}
+
+static inline bool fc_frame_is_cmd(const struct fc_frame *fp)
+{
+	return fc_frame_rctl(fp) == FC_RCTL_DD_UNSOL_CMD;
+}
+
+static inline bool fc_frame_is_read(const struct fc_frame *fp)
+{
+	if (fc_frame_is_cmd(fp) && fr_cmd(fp))
+		return fr_dir(fp) == DMA_FROM_DEVICE;
+	return false;
+}
+
+static inline bool fc_frame_is_write(const struct fc_frame *fp)
+{
+	if (fc_frame_is_cmd(fp) && fr_cmd(fp))
+		return fr_dir(fp) == DMA_TO_DEVICE;
+	return false;
+}
+
+/*
+ * Check for leaks.
+ * Print the frame header of any currently allocated frame, assuming there
+ * should be none at this point.
+ */
+void fc_frame_leak_check(void);
+
+#endif /* _FC_FRAME_H_ */

include/scsi/libfc.h

···
+/*
+ * Copyright(c) 2007 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Maintained at www.Open-FCoE.org
+ */
+
+#ifndef _LIBFC_H_
+#define _LIBFC_H_
+
+#include <linux/timer.h>
+#include <linux/if.h>
+
+#include <scsi/scsi_transport.h>
+#include <scsi/scsi_transport_fc.h>
+
+#include <scsi/fc/fc_fcp.h>
+#include <scsi/fc/fc_ns.h>
+#include <scsi/fc/fc_els.h>
+#include <scsi/fc/fc_gs.h>
+
+#include <scsi/fc_frame.h>
+
+#define LIBFC_DEBUG
+
+#ifdef LIBFC_DEBUG
+/* Log messages */
+#define FC_DBG(fmt, args...)						\
+	do {								\
+		printk(KERN_INFO "%s " fmt, __func__, ##args);		\
+	} while (0)
+#else
+#define FC_DBG(fmt, args...)
+#endif
+
+/*
+ * libfc error codes
+ */
+#define	FC_NO_ERR	0	/* no error */
+#define	FC_EX_TIMEOUT	1	/* Exchange timeout */
+#define	FC_EX_CLOSED	2	/* Exchange closed */
+
+/* some helpful macros */
+
+#define ntohll(x) be64_to_cpu(x)
+#define htonll(x) cpu_to_be64(x)
+
+#define ntoh24(p) (((p)[0] << 16) | ((p)[1] << 8) | ((p)[2]))
+
+#define hton24(p, v)	do {			\
+		p[0] = (((v) >> 16) & 0xFF);	\
+		p[1] = (((v) >> 8) & 0xFF);	\
+		p[2] = ((v) & 0xFF);		\
+	} while (0)
+
+/*
+ * FC HBA status
+ */
+#define FC_PAUSE		    (1 << 1)
+#define FC_LINK_UP		    (1 << 0)
+
+enum fc_lport_state {
+	LPORT_ST_NONE = 0,
+	LPORT_ST_FLOGI,
+	LPORT_ST_DNS,
+	LPORT_ST_RPN_ID,
+	LPORT_ST_RFT_ID,
+	LPORT_ST_SCR,
+	LPORT_ST_READY,
+	LPORT_ST_LOGO,
+	LPORT_ST_RESET
+};
+
+enum fc_disc_event {
+	DISC_EV_NONE = 0,
+	DISC_EV_SUCCESS,
+	DISC_EV_FAILED
+};
+
+enum fc_rport_state {
+	RPORT_ST_NONE = 0,
+	RPORT_ST_INIT,		/* initialized */
+	RPORT_ST_PLOGI,		/* waiting for PLOGI completion */
+	RPORT_ST_PRLI,		/* waiting for PRLI completion */
+	RPORT_ST_RTV,		/* waiting for RTV completion */
+	RPORT_ST_READY,		/* ready for use */
+	RPORT_ST_LOGO,		/* port logout sent */
+};
+
+enum fc_rport_trans_state {
+	FC_PORTSTATE_ROGUE,
+	FC_PORTSTATE_REAL,
+};
+
+/**
+ * struct fc_disc_port - temporary discovery port to hold rport identifiers
+ * @lp: Fibre Channel host port instance
+ * @peers: node for list management during discovery and RSCN processing
+ * @ids: identifiers structure to pass to fc_remote_port_add()
+ * @rport_work: work struct for starting the rport state machine
+ */
+struct fc_disc_port {
+	struct fc_lport             *lp;
+	struct list_head            peers;
+	struct fc_rport_identifiers ids;
+	struct work_struct	    rport_work;
+};
+
+enum fc_rport_event {
+	RPORT_EV_NONE = 0,
+	RPORT_EV_CREATED,
+	RPORT_EV_FAILED,
+	RPORT_EV_STOP,
+	RPORT_EV_LOGO
+};
+
+struct fc_rport_operations {
+	void (*event_callback)(struct fc_lport *, struct fc_rport *,
+			       enum fc_rport_event);
+};
+
+/**
+ * struct fc_rport_libfc_priv - libfc internal information about a remote port
+ * @local_port: Fibre Channel host port instance
+ * @rp_state: state tracks progress of PLOGI, PRLI, and RTV exchanges
+ * @flags: REC and RETRY supported flags
+ * @max_seq: maximum number of concurrent sequences
+ * @retries: retry count in current state
+ * @e_d_tov: error detect timeout value (in msec)
+ * @r_a_tov: resource allocation timeout value (in msec)
+ * @rp_mutex: mutex protects rport
+ * @retry_work:
+ * @event_callback: Callback for rport READY, FAILED or LOGO
+ */
+struct fc_rport_libfc_priv {
+	struct fc_lport		   *local_port;
+	enum fc_rport_state        rp_state;
+	u16			   flags;
+	#define FC_RP_FLAGS_REC_SUPPORTED	(1 << 0)
+	#define FC_RP_FLAGS_RETRY		(1 << 1)
+	u16		           max_seq;
+	unsigned int	           retries;
+	unsigned int	           e_d_tov;
+	unsigned int	           r_a_tov;
+	enum fc_rport_trans_state  trans_state;
+	struct mutex               rp_mutex;
+	struct delayed_work	   retry_work;
+	enum fc_rport_event        event;
+	struct fc_rport_operations *ops;
+	struct list_head           peers;
+	struct work_struct         event_work;
+};
+
+#define PRIV_TO_RPORT(x)						\
+	(struct fc_rport *)((void *)x - sizeof(struct fc_rport));
+#define RPORT_TO_PRIV(x)						\
+	(struct fc_rport_libfc_priv *)((void *)x + sizeof(struct fc_rport));
+
+struct fc_rport *fc_rport_rogue_create(struct fc_disc_port *);
+
+static inline void fc_rport_set_name(struct fc_rport *rport, u64 wwpn, u64 wwnn)
+{
+	rport->node_name = wwnn;
+	rport->port_name = wwpn;
+}
+
+/*
+ * fcoe stats structure
+ */
+struct fcoe_dev_stats {
+	u64		SecondsSinceLastReset;
+	u64		TxFrames;
+	u64		TxWords;
+	u64		RxFrames;
+	u64		RxWords;
+	u64		ErrorFrames;
+	u64		DumpedFrames;
+	u64		LinkFailureCount;
+	u64		LossOfSignalCount;
+	u64		InvalidTxWordCount;
+	u64		InvalidCRCCount;
+	u64		InputRequests;
+	u64		OutputRequests;
+	u64		ControlRequests;
+	u64		InputMegabytes;
+	u64		OutputMegabytes;
+};
+
+/*
+ * els data is used for passing ELS respone specific
+ * data to send ELS response mainly using infomation
+ * in exchange and sequence in EM layer.
+ */
+struct fc_seq_els_data {
+	struct fc_frame *fp;
+	enum fc_els_rjt_reason reason;
+	enum fc_els_rjt_explan explan;
+};
+
+/*
+ * FCP request structure, one for each scsi cmd request
+ */
+struct fc_fcp_pkt {
+	/*
+	 * housekeeping stuff
+	 */
+	struct fc_lport *lp;	/* handle to hba struct */
+	u16		state;		/* scsi_pkt state state */
+	u16		tgt_flags;	/* target flags	 */
+	atomic_t	ref_cnt;	/* fcp pkt ref count */
+	spinlock_t	scsi_pkt_lock;	/* Must be taken before the host lock
+					 * if both are held at the same time */
+	/*
+	 * SCSI I/O related stuff
+	 */
+	struct scsi_cmnd *cmd;		/* scsi command pointer. set/clear
+					 * under host lock */
+	struct list_head list;		/* tracks queued commands. access under
+					 * host lock */
+	/*
+	 * timeout related stuff
+	 */
+	struct timer_list timer;	/* command timer */
+	struct completion tm_done;
+	int	wait_for_comp;
+	unsigned long	start_time;	/* start jiffie */
+	unsigned long	end_time;	/* end jiffie */
+	unsigned long	last_pkt_time;	 /* jiffies of last frame received */
+
+	/*
+	 * scsi cmd and data transfer information
+	 */
+	u32		data_len;
+	/*
+	 * transport related veriables
+	 */
+	struct fcp_cmnd cdb_cmd;
+	size_t		xfer_len;
+	u32		xfer_contig_end; /* offset of end of contiguous xfer */
+	u16		max_payload;	/* max payload size in bytes */
+
+	/*
+	 * scsi/fcp return status
+	 */
+	u32		io_status;	/* SCSI result upper 24 bits */
+	u8		cdb_status;
+	u8		status_code;	/* FCP I/O status */
+	/* bit 3 Underrun bit 2: overrun */
+	u8		scsi_comp_flags;
+	u32		req_flags;	/* bit 0: read bit:1 write */
+	u32		scsi_resid;	/* residule length */
+
+	struct fc_rport	*rport;		/* remote port pointer */
+	struct fc_seq	*seq_ptr;	/* current sequence pointer */
+	/*
+	 * Error Processing
+	 */
+	u8		recov_retry;	/* count of recovery retries */
+	struct fc_seq	*recov_seq;	/* sequence for REC or SRR */
+};
+
+/*
+ * Structure and function definitions for managing Fibre Channel Exchanges
+ * and Sequences
+ *
+ * fc_exch holds state for one exchange and links to its active sequence.
+ *
+ * fc_seq holds the state for an individual sequence.
+ */
+
+struct fc_exch_mgr;
+
+/*
+ * Sequence.
+ */
+struct fc_seq {
+	u8	id;		/* seq ID */
+	u16	ssb_stat;	/* status flags for sequence status block */
+	u16	cnt;		/* frames sent so far on sequence */
+	u32	rec_data;	/* FC-4 value for REC */
+};
+
+#define FC_EX_DONE		(1 << 0) /* ep is completed */
+#define FC_EX_RST_CLEANUP	(1 << 1) /* reset is forcing completion */
+
+/*
+ * Exchange.
+ *
+ * Locking notes: The ex_lock protects following items:
+ *	state, esb_stat, f_ctl, seq.ssb_stat
+ *	seq_id
+ *	sequence allocation
+ */
+struct fc_exch {
+	struct fc_exch_mgr *em;		/* exchange manager */
+	u32		state;		/* internal driver state */
+	u16		xid;		/* our exchange ID */
+	struct list_head	ex_list;	/* free or busy list linkage */
+	spinlock_t	ex_lock;	/* lock covering exchange state */
+	atomic_t	ex_refcnt;	/* reference counter */
+	struct delayed_work timeout_work; /* timer for upper level protocols */
+	struct fc_lport	*lp;		/* fc device instance */
+	u16		oxid;		/* originator's exchange ID */
+	u16		rxid;		/* responder's exchange ID */
+	u32		oid;		/* originator's FCID */
+	u32		sid;		/* source FCID */
+	u32		did;		/* destination FCID */
+	u32		esb_stat;	/* exchange status for ESB */
+	u32		r_a_tov;	/* r_a_tov from rport (msec) */
+	u8		seq_id;		/* next sequence ID to use */
+	u32		f_ctl;		/* F_CTL flags for sequences */
+	u8		fh_type;	/* frame type */
+	enum fc_class	class;		/* class of service */
+	struct fc_seq	seq;		/* single sequence */
+	/*
+	 * Handler for responses to this current exchange.
+	 */
+	void		(*resp)(struct fc_seq *, struct fc_frame *, void *);
+	void		(*destructor)(struct fc_seq *, void *);
+	/*
+	 * arg is passed as void pointer to exchange
+	 * resp and destructor handlers
+	 */
+	void		*arg;
+};
+#define	fc_seq_exch(sp) container_of(sp, struct fc_exch, seq)
+
+struct libfc_function_template {
+
+	/**
+	 * Mandatory Fields
+	 *
+	 * These handlers must be implemented by the LLD.
+	 */
+
+	/*
+	 * Interface to send a FC frame
+	 */
+	int (*frame_send)(struct fc_lport *lp, struct fc_frame *fp);
+
+	/**
+	 * Optional Fields
+	 *
+	 * The LLD may choose to implement any of the following handlers.
+	 * If LLD doesn't specify hander and leaves its pointer NULL then
+	 * the default libfc function will be used for that handler.
+	 */
+
+	/**
+	 * ELS/CT interfaces
+	 */
+
+	/*
+	 * elsct_send - sends ELS/CT frame
+	 */
+	struct fc_seq *(*elsct_send)(struct fc_lport *lport,
+				     struct fc_rport *rport,
+				     struct fc_frame *fp,
+				     unsigned int op,
+				     void (*resp)(struct fc_seq *,
+					     struct fc_frame *fp,
+					     void *arg),
+				     void *arg, u32 timer_msec);
+	/**
+	 * Exhance Manager interfaces
+	 */
+
+	/*
+	 * Send the FC frame payload using a new exchange and sequence.
+	 *
+	 * The frame pointer with some of the header's fields must be
+	 * filled before calling exch_seq_send(), those fields are,
+	 *
+	 * - routing control
+	 * - FC port did
+	 * - FC port sid
+	 * - FC header type
+	 * - frame control
+	 * - parameter or relative offset
+	 *
+	 * The exchange response handler is set in this routine to resp()
+	 * function pointer. It can be called in two scenarios: if a timeout
+	 * occurs or if a response frame is received for the exchange. The
+	 * fc_frame pointer in response handler will also indicate timeout
+	 * as error using IS_ERR related macros.
+	 *
+	 * The exchange destructor handler is also set in this routine.
+	 * The destructor handler is invoked by EM layer when exchange
+	 * is about to free, this can be used by caller to free its
+	 * resources along with exchange free.
+	 *
+	 * The arg is passed back to resp and destructor handler.
+	 *
+	 * The timeout value (in msec) for an exchange is set if non zero
+	 * timer_msec argument is specified. The timer is canceled when
+	 * it fires or when the exchange is done. The exchange timeout handler
+	 * is registered by EM layer.
+	 */
+	struct fc_seq *(*exch_seq_send)(struct fc_lport *lp,
+					struct fc_frame *fp,
+					void (*resp)(struct fc_seq *sp,
+						     struct fc_frame *fp,
+						     void *arg),
+					void (*destructor)(struct fc_seq *sp,
+							   void *arg),
+					void *arg, unsigned int timer_msec);
+
+	/*
+	 * send a frame using existing sequence and exchange.
+	 */
+	int (*seq_send)(struct fc_lport *lp, struct fc_seq *sp,
+			struct fc_frame *fp);
+
+	/*
+	 * Send ELS response using mainly infomation
+	 * in exchange and sequence in EM layer.
+	 */
+	void (*seq_els_rsp_send)(struct fc_seq *sp, enum fc_els_cmd els_cmd,
+				 struct fc_seq_els_data *els_data);
+
+	/*
+	 * Abort an exchange and sequence. Generally called because of a
+	 * exchange timeout or an abort from the upper layer.
+	 *
+	 * A timer_msec can be specified for abort timeout, if non-zero
+	 * timer_msec value is specified then exchange resp handler
+	 * will be called with timeout error if no response to abort.
+	 */
+	int (*seq_exch_abort)(const struct fc_seq *req_sp,
+			      unsigned int timer_msec);
+
+	/*
+	 * Indicate that an exchange/sequence tuple is complete and the memory
+	 * allocated for the related objects may be freed.
+	 */
+	void (*exch_done)(struct fc_seq *sp);
+
+	/*
+	 * Assigns a EM and a free XID for an new exchange and then
+	 * allocates a new exchange and sequence pair.
+	 * The fp can be used to determine free XID.
+	 */
+	struct fc_exch *(*exch_get)(struct fc_lport *lp, struct fc_frame *fp);
+
+	/*
+	 * Release previously assigned XID by exch_get API.
+	 * The LLD may implement this if XID is assigned by LLD
+	 * in exch_get().
+	 */
+	void (*exch_put)(struct fc_lport *lp, struct fc_exch_mgr *mp,
+			 u16 ex_id);
+
+	/*
+	 * Start a new sequence on the same exchange/sequence tuple.
+	 */
+	struct fc_seq *(*seq_start_next)(struct fc_seq *sp);
+
+	/*
+	 * Reset an exchange manager, completing all sequences and exchanges.
+	 * If s_id is non-zero, reset only exchanges originating from that FID.
+	 * If d_id is non-zero, reset only exchanges sending to that FID.
+	 */
+	void (*exch_mgr_reset)(struct fc_exch_mgr *,
+			       u32 s_id, u32 d_id);
+
+	void (*rport_flush_queue)(void);
+	/**
+	 * Local Port interfaces
+	 */
+
+	/*
+	 * Receive a frame to a local port.
+	 */
+	void (*lport_recv)(struct fc_lport *lp, struct fc_seq *sp,
+			   struct fc_frame *fp);
+
+	int (*lport_reset)(struct fc_lport *);
+
+	/**
+	 * Remote Port interfaces
+	 */
+
+	/*
+	 * Initiates the RP state machine. It is called from the LP module.
+	 * This function will issue the following commands to the N_Port
+	 * identified by the FC ID provided.
+	 *
+	 * - PLOGI
+	 * - PRLI
+	 * - RTV
+	 */
+	int (*rport_login)(struct fc_rport *rport);
+
+	/*
+	 * Logoff, and remove the rport from the transport if
+	 * it had been added. This will send a LOGO to the target.
+	 */
+	int (*rport_logoff)(struct fc_rport *rport);
+
+	/*
+	 * Recieve a request from a remote port.
+	 */
+	void (*rport_recv_req)(struct fc_seq *, struct fc_frame *,
+			       struct fc_rport *);
+
+	struct fc_rport *(*rport_lookup)(const struct fc_lport *, u32);
+
+	/**
+	 * FCP interfaces
+	 */
+
+	/*
+	 * Send a fcp cmd from fsp pkt.
+	 * Called with the SCSI host lock unlocked and irqs disabled.
+	 *
+	 * The resp handler is called when FCP_RSP received.
+	 *
+	 */
+	int (*fcp_cmd_send)(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
+			    void (*resp)(struct fc_seq *, struct fc_frame *fp,
+					 void *arg));
+
+	/*
+	 * Used at least durring linkdown and reset
+	 */
+	void (*fcp_cleanup)(struct fc_lport *lp);
+
+	/*
+	 * Abort all I/O on a local port
+	 */
+	void (*fcp_abort_io)(struct fc_lport *lp);
+
+	/**
+	 * Discovery interfaces
+	 */
+
+	void (*disc_recv_req)(struct fc_seq *,
+			      struct fc_frame *, struct fc_lport *);
+
+	/*
+	 * Start discovery for a local port.
+	 */
+	void (*disc_start)(void (*disc_callback)(struct fc_lport *,
+						 enum fc_disc_event),
+			   struct fc_lport *);
+
+	/*
+	 * Stop discovery for a given lport. This will remove
+	 * all discovered rports
+	 */
+	void (*disc_stop) (struct fc_lport *);
+
+	/*
+	 * Stop discovery for a given lport. This will block
+	 * until all discovered rports are deleted from the
+	 * FC transport class
+	 */
+	void (*disc_stop_final) (struct fc_lport *);
+};
+
+/* information used by the discovery layer */
+struct fc_disc {
+	unsigned char		retry_count;
+	unsigned char		delay;
+	unsigned char		pending;
+	unsigned char		requested;
+	unsigned short		seq_count;
+	unsigned char		buf_len;
+	enum fc_disc_event	event;
+
+	void (*disc_callback)(struct fc_lport *,
+			      enum fc_disc_event);
+
+	struct list_head	 rports;
+	struct fc_lport		*lport;
+	struct mutex		disc_mutex;
+	struct fc_gpn_ft_resp	partial_buf;	/* partial name buffer */
+	struct delayed_work	disc_work;
+};
+
+struct fc_lport {
+	struct list_head list;
+
+	/* Associations */
+	struct Scsi_Host	*host;
+	struct fc_exch_mgr	*emp;
+	struct fc_rport		*dns_rp;
+	struct fc_rport		*ptp_rp;
+	void			*scsi_priv;
+	struct fc_disc          disc;
+
+	/* Operational Information */
+	struct libfc_function_template tt;
+	u16			link_status;
+	enum fc_lport_state	state;
+	unsigned long		boot_time;
+
+	struct fc_host_statistics host_stats;
+	struct fcoe_dev_stats	*dev_stats[NR_CPUS];
+	u64			wwpn;
+	u64			wwnn;
+	u8			retry_count;
+
+	/* Capabilities */
+	u32			sg_supp:1;	/* scatter gather supported */
+	u32			seq_offload:1;	/* seq offload supported */
+	u32			crc_offload:1;	/* crc offload supported */
+	u32			lro_enabled:1;	/* large receive offload */
+	u32			mfs;	        /* max FC payload size */
+	unsigned int		service_params;
+	unsigned int		e_d_tov;
+	unsigned int		r_a_tov;
+	u8			max_retry_count;
+	u16			link_speed;
+	u16			link_supported_speeds;
+	u16			lro_xid;	/* max xid for fcoe lro */
+	struct fc_ns_fts	fcts;	        /* FC-4 type masks */
+	struct fc_els_rnid_gen	rnid_gen;	/* RNID information */
+
+	/* Semaphores */
+	struct mutex lp_mutex;
+
+	/* Miscellaneous */
+	struct delayed_work	retry_work;
+	struct delayed_work	disc_work;
+};
+
+/**
+ * FC_LPORT HELPER FUNCTIONS
+ *****************************/
+static inline void *lport_priv(const struct fc_lport *lp)
+{
+	return (void *)(lp + 1);
+}
+
+static inline int fc_lport_test_ready(struct fc_lport *lp)
+{
+	return lp->state == LPORT_ST_READY;
+}
+
+static inline void fc_set_wwnn(struct fc_lport *lp, u64 wwnn)
+{
+	lp->wwnn = wwnn;
+}
+
+static inline void fc_set_wwpn(struct fc_lport *lp, u64 wwnn)
+{
+	lp->wwpn = wwnn;
+}
+
+static inline void fc_lport_state_enter(struct fc_lport *lp,
+					enum fc_lport_state state)
+{
+	if (state != lp->state)
+		lp->retry_count = 0;
+	lp->state = state;
+}
+
+
+/**
+ * LOCAL PORT LAYER
+ *****************************/
+int fc_lport_init(struct fc_lport *lp);
+
+/*
+ * Destroy the specified local port by finding and freeing all
+ * fc_rports associated with it and then by freeing the fc_lport
+ * itself.
+ */
+int fc_lport_destroy(struct fc_lport *lp);
+
+/*
+ * Logout the specified local port from the fabric
+ */
+int fc_fabric_logoff(struct fc_lport *lp);
+
+/*
+ * Initiate the LP state machine. This handler will use fc_host_attr
+ * to store the FLOGI service parameters, so fc_host_attr must be
+ * initialized before calling this handler.
+ */
+int fc_fabric_login(struct fc_lport *lp);
+
+/*
+ * The link is up for the given local port.
+ */
+void fc_linkup(struct fc_lport *);
+
+/*
+ * Link is down for the given local port.
+ */
+void fc_linkdown(struct fc_lport *);
+
+/*
+ * Pause and unpause traffic.
+ */
+void fc_pause(struct fc_lport *);
+void fc_unpause(struct fc_lport *);
+
+/*
+ * Configure the local port.
+ */
+int fc_lport_config(struct fc_lport *);
+
+/*
+ * Reset the local port.
+ */
+int fc_lport_reset(struct fc_lport *);
+
+/*
+ * Set the mfs or reset
+ */
+int fc_set_mfs(struct fc_lport *lp, u32 mfs);
+
+
+/**
+ * REMOTE PORT LAYER
+ *****************************/
+int fc_rport_init(struct fc_lport *lp);
+void fc_rport_terminate_io(struct fc_rport *rp);
+
+/**
+ * DISCOVERY LAYER
+ *****************************/
+int fc_disc_init(struct fc_lport *lp);
+
+
+/**
+ * SCSI LAYER
+ *****************************/
+/*
+ * Initialize the SCSI block of libfc
+ */
+int fc_fcp_init(struct fc_lport *);
+
+/*
+ * This section provides an API which allows direct interaction
+ * with the SCSI-ml. Each of these functions satisfies a function
+ * pointer defined in Scsi_Host and therefore is always called
+ * directly from the SCSI-ml.
+ */
+int fc_queuecommand(struct scsi_cmnd *sc_cmd,
+		    void (*done)(struct scsi_cmnd *));
+
+/*
+ * complete processing of a fcp packet
+ *
+ * This function may sleep if a fsp timer is pending.
+ * The host lock must not be held by caller.
+ */
+void fc_fcp_complete(struct fc_fcp_pkt *fsp);
+
+/*
+ * Send an ABTS frame to the target device. The sc_cmd argument
+ * is a pointer to the SCSI command to be aborted.
+ */
+int fc_eh_abort(struct scsi_cmnd *sc_cmd);
+
+/*
+ * Reset a LUN by sending send the tm cmd to the target.
+ */
+int fc_eh_device_reset(struct scsi_cmnd *sc_cmd);
+
+/*
+ * Reset the host adapter.
+ */
+int fc_eh_host_reset(struct scsi_cmnd *sc_cmd);
+
+/*
+ * Check rport status.
+ */
+int fc_slave_alloc(struct scsi_device *sdev);
+
+/*
+ * Adjust the queue depth.
+ */
+int fc_change_queue_depth(struct scsi_device *sdev, int qdepth);
+
+/*
+ * Change the tag type.
+ */
+int fc_change_queue_type(struct scsi_device *sdev, int tag_type);
+
+/*
+ * Free memory pools used by the FCP layer.
+ */
+void fc_fcp_destroy(struct fc_lport *);
+
+/**
+ * ELS/CT interface
+ *****************************/
+/*
+ * Initializes ELS/CT interface
+ */
+int fc_elsct_init(struct fc_lport *lp);
+
+
+/**
+ * EXCHANGE MANAGER LAYER
+ *****************************/
+/*
+ * Initializes Exchange Manager related
+ * function pointers in struct libfc_function_template.
+ */
+int fc_exch_init(struct fc_lport *lp);
+
+/*
+ * Allocates an Exchange Manager (EM).
+ *
+ * The EM manages exchanges for their allocation and
+ * free, also allows exchange lookup for received
+ * frame.
+ *
+ * The class is used for initializing FC class of
+ * allocated exchange from EM.
+ *
+ * The min_xid and max_xid will limit new
+ * exchange ID (XID) within this range for
+ * a new exchange.
+ * The LLD may choose to have multiple EMs,
+ * e.g. one EM instance per CPU receive thread in LLD.
+ * The LLD can use exch_get() of struct libfc_function_template
+ * to specify XID for a new exchange within
+ * a specified EM instance.
+ *
+ * The em_idx to uniquely identify an EM instance.
+ */
+struct fc_exch_mgr *fc_exch_mgr_alloc(struct fc_lport *lp,
+				      enum fc_class class,
+				      u16 min_xid,
+				      u16 max_xid);
+
+/*
+ * Free an exchange manager.
+ */
+void fc_exch_mgr_free(struct fc_exch_mgr *mp);
+
+/*
+ * Receive a frame on specified local port and exchange manager.
+ */
+void fc_exch_recv(struct fc_lport *lp, struct fc_exch_mgr *mp,
+		  struct fc_frame *fp);
+
+/*
+ * This function is for exch_seq_send function pointer in
+ * struct libfc_function_template, see comment block on
+ * exch_seq_send for description of this function.
+ */
+struct fc_seq *fc_exch_seq_send(struct fc_lport *lp,
+				struct fc_frame *fp,
+				void (*resp)(struct fc_seq *sp,
+					     struct fc_frame *fp,
+					     void *arg),
+				void (*destructor)(struct fc_seq *sp,
+						   void *arg),
+				void *arg, u32 timer_msec);
+
+/*
+ * send a frame using existing sequence and exchange.
+ */
+int fc_seq_send(struct fc_lport *lp, struct fc_seq *sp, struct fc_frame *fp);
+
+/*
+ * Send ELS response using mainly infomation
+ * in exchange and sequence in EM layer.
+ */
+void fc_seq_els_rsp_send(struct fc_seq *sp, enum fc_els_cmd els_cmd,
+			 struct fc_seq_els_data *els_data);
+
+/*
+ * This function is for seq_exch_abort function pointer in
+ * struct libfc_function_template, see comment block on
+ * seq_exch_abort for description of this function.
+ */
+int fc_seq_exch_abort(const struct fc_seq *req_sp, unsigned int timer_msec);
+
+/*
+ * Indicate that an exchange/sequence tuple is complete and the memory
+ * allocated for the related objects may be freed.
+ */
+void fc_exch_done(struct fc_seq *sp);
+
+/*
+ * Assigns a EM and XID for a frame and then allocates
+ * a new exchange and sequence pair.
+ * The fp can be used to determine free XID.
+ */
+struct fc_exch *fc_exch_get(struct fc_lport *lp, struct fc_frame *fp);
+
+/*
+ * Allocate a new exchange and sequence pair.
+ * if ex_id is zero then next free exchange id
+ * from specified exchange manger mp will be assigned.
+ */
+struct fc_exch *fc_exch_alloc(struct fc_exch_mgr *mp,
+			      struct fc_frame *fp, u16 ex_id);
+/*
+ * Start a new sequence on the same exchange as the supplied sequence.
+ */
+struct fc_seq *fc_seq_start_next(struct fc_seq *sp);
+
+/*
+ * Reset an exchange manager, completing all sequences and exchanges.
+ * If s_id is non-zero, reset only exchanges originating from that FID.
+ * If d_id is non-zero, reset only exchanges sending to that FID.
+ */
+void fc_exch_mgr_reset(struct fc_exch_mgr *, u32 s_id, u32 d_id);
+
+/*
+ * Functions for fc_functions_template
+ */
+void fc_get_host_speed(struct Scsi_Host *shost);
+void fc_get_host_port_type(struct Scsi_Host *shost);
+void fc_get_host_port_state(struct Scsi_Host *shost);
+void fc_set_rport_loss_tmo(struct fc_rport *rport, u32 timeout);
+struct fc_host_statistics *fc_get_host_stats(struct Scsi_Host *);
+
+/*
+ * module setup functions.
+ */
+int fc_setup_exch_mgr(void);
+void fc_destroy_exch_mgr(void);
+int fc_setup_rport(void);
+void fc_destroy_rport(void);
+
+#endif /* _LIBFC_H_ */