scsi: qedf: Add QLogic FastLinQ offload FCoE driver framework.

The QLogic FastLinQ Driver for FCoE (qedf) is the FCoE specific module
for 41000 Series Converged Network Adapters by QLogic. This patch
consists of following changes:

- MAINTAINERS Makefile and Kconfig changes for qedf
- PCI driver registration
- libfc/fcoe host level initialization
- SCSI host template initialization and callbacks
- Debugfs and log level infrastructure
- Link handling
- Firmware interface structures
- QED core module initialization
- Light L2 interface callbacks
- I/O request initialization
- Firmware I/O completion handling
- Firmware ELS request/response handling
- FIP request/response handled by the driver itself

Signed-off-by: Nilesh Javali <nilesh.javali@cavium.com>
Signed-off-by: Manish Rangankar <manish.rangankar@cavium.com>
Signed-off-by: Saurav Kashyap <saurav.kashyap@cavium.com>
Signed-off-by: Arun Easi <arun.easi@cavium.com>
Signed-off-by: Chad Dupuis <chad.dupuis@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 949 insertions, 0 deletions

diff --git a/drivers/scsi/qedf/qedf_els.c b/drivers/scsi/qedf/qedf_els.c
new file mode 100644
index 000000000000..78f1c252b649
--- /dev/null
+++ b/drivers/scsi/qedf/qedf_els.c
@@ -0,0 +1,949 @@
+/*
+ *  QLogic FCoE Offload Driver
+ *  Copyright (c) 2016 Cavium Inc.
+ *
+ *  This software is available under the terms of the GNU General Public License
+ *  (GPL) Version 2, available from the file COPYING in the main directory of
+ *  this source tree.
+ */
+#include "qedf.h"
+
+/* It's assumed that the lock is held when calling this function. */
+static int qedf_initiate_els(struct qedf_rport *fcport, unsigned int op,
+	void *data, uint32_t data_len,
+	void (*cb_func)(struct qedf_els_cb_arg *cb_arg),
+	struct qedf_els_cb_arg *cb_arg, uint32_t timer_msec)
+{
+	struct qedf_ctx *qedf = fcport->qedf;
+	struct fc_lport *lport = qedf->lport;
+	struct qedf_ioreq *els_req;
+	struct qedf_mp_req *mp_req;
+	struct fc_frame_header *fc_hdr;
+	struct fcoe_task_context *task;
+	int rc = 0;
+	uint32_t did, sid;
+	uint16_t xid;
+	uint32_t start_time = jiffies / HZ;
+	uint32_t current_time;
+
+	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "Sending ELS\n");
+
+	rc = fc_remote_port_chkready(fcport->rport);
+	if (rc) {
+		QEDF_ERR(&(qedf->dbg_ctx), "els 0x%x: rport not ready\n", op);
+		rc = -EAGAIN;
+		goto els_err;
+	}
+	if (lport->state != LPORT_ST_READY || !(lport->link_up)) {
+		QEDF_ERR(&(qedf->dbg_ctx), "els 0x%x: link is not ready\n",
+			  op);
+		rc = -EAGAIN;
+		goto els_err;
+	}
+
+	if (!(test_bit(QEDF_RPORT_SESSION_READY, &fcport->flags))) {
+		QEDF_ERR(&(qedf->dbg_ctx), "els 0x%x: fcport not ready\n", op);
+		rc = -EINVAL;
+		goto els_err;
+	}
+
+retry_els:
+	els_req = qedf_alloc_cmd(fcport, QEDF_ELS);
+	if (!els_req) {
+		current_time = jiffies / HZ;
+		if ((current_time - start_time) > 10) {
+			QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
+				   "els: Failed els 0x%x\n", op);
+			rc = -ENOMEM;
+			goto els_err;
+		}
+		mdelay(20 * USEC_PER_MSEC);
+		goto retry_els;
+	}
+
+	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "initiate_els els_req = "
+		   "0x%p cb_arg = %p xid = %x\n", els_req, cb_arg,
+		   els_req->xid);
+	els_req->sc_cmd = NULL;
+	els_req->cmd_type = QEDF_ELS;
+	els_req->fcport = fcport;
+	els_req->cb_func = cb_func;
+	cb_arg->io_req = els_req;
+	cb_arg->op = op;
+	els_req->cb_arg = cb_arg;
+	els_req->data_xfer_len = data_len;
+
+	/* Record which cpu this request is associated with */
+	els_req->cpu = smp_processor_id();
+
+	mp_req = (struct qedf_mp_req *)&(els_req->mp_req);
+	rc = qedf_init_mp_req(els_req);
+	if (rc) {
+		QEDF_ERR(&(qedf->dbg_ctx), "ELS MP request init failed\n");
+		kref_put(&els_req->refcount, qedf_release_cmd);
+		goto els_err;
+	} else {
+		rc = 0;
+	}
+
+	/* Fill ELS Payload */
+	if ((op >= ELS_LS_RJT) && (op <= ELS_AUTH_ELS)) {
+		memcpy(mp_req->req_buf, data, data_len);
+	} else {
+		QEDF_ERR(&(qedf->dbg_ctx), "Invalid ELS op 0x%x\n", op);
+		els_req->cb_func = NULL;
+		els_req->cb_arg = NULL;
+		kref_put(&els_req->refcount, qedf_release_cmd);
+		rc = -EINVAL;
+	}
+
+	if (rc)
+		goto els_err;
+
+	/* Fill FC header */
+	fc_hdr = &(mp_req->req_fc_hdr);
+
+	did = fcport->rdata->ids.port_id;
+	sid = fcport->sid;
+
+	__fc_fill_fc_hdr(fc_hdr, FC_RCTL_ELS_REQ, sid, did,
+			   FC_TYPE_ELS, FC_FC_FIRST_SEQ | FC_FC_END_SEQ |
+			   FC_FC_SEQ_INIT, 0);
+
+	/* Obtain exchange id */
+	xid = els_req->xid;
+
+	/* Initialize task context for this IO request */
+	task = qedf_get_task_mem(&qedf->tasks, xid);
+	qedf_init_mp_task(els_req, task);
+
+	/* Put timer on original I/O request */
+	if (timer_msec)
+		qedf_cmd_timer_set(qedf, els_req, timer_msec);
+
+	qedf_add_to_sq(fcport, xid, 0, FCOE_TASK_TYPE_MIDPATH, 0);
+
+	/* Ring doorbell */
+	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "Ringing doorbell for ELS "
+		   "req\n");
+	qedf_ring_doorbell(fcport);
+els_err:
+	return rc;
+}
+
+void qedf_process_els_compl(struct qedf_ctx *qedf, struct fcoe_cqe *cqe,
+	struct qedf_ioreq *els_req)
+{
+	struct fcoe_task_context *task_ctx;
+	struct scsi_cmnd *sc_cmd;
+	uint16_t xid;
+	struct fcoe_cqe_midpath_info *mp_info;
+
+	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "Entered with xid = 0x%x"
+		   " cmd_type = %d.\n", els_req->xid, els_req->cmd_type);
+
+	/* Kill the ELS timer */
+	cancel_delayed_work(&els_req->timeout_work);
+
+	xid = els_req->xid;
+	task_ctx = qedf_get_task_mem(&qedf->tasks, xid);
+	sc_cmd = els_req->sc_cmd;
+
+	/* Get ELS response length from CQE */
+	mp_info = &cqe->cqe_info.midpath_info;
+	els_req->mp_req.resp_len = mp_info->data_placement_size;
+
+	/* Parse ELS response */
+	if ((els_req->cb_func) && (els_req->cb_arg)) {
+		els_req->cb_func(els_req->cb_arg);
+		els_req->cb_arg = NULL;
+	}
+
+	kref_put(&els_req->refcount, qedf_release_cmd);
+}
+
+static void qedf_rrq_compl(struct qedf_els_cb_arg *cb_arg)
+{
+	struct qedf_ioreq *orig_io_req;
+	struct qedf_ioreq *rrq_req;
+	struct qedf_ctx *qedf;
+	int refcount;
+
+	rrq_req = cb_arg->io_req;
+	qedf = rrq_req->fcport->qedf;
+
+	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "Entered.\n");
+
+	orig_io_req = cb_arg->aborted_io_req;
+
+	if (!orig_io_req)
+		goto out_free;
+
+	if (rrq_req->event != QEDF_IOREQ_EV_ELS_TMO &&
+	    rrq_req->event != QEDF_IOREQ_EV_ELS_ERR_DETECT)
+		cancel_delayed_work_sync(&orig_io_req->timeout_work);
+
+	refcount = atomic_read(&orig_io_req->refcount.refcount);
+	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "rrq_compl: orig io = %p,"
+		   " orig xid = 0x%x, rrq_xid = 0x%x, refcount=%d\n",
+		   orig_io_req, orig_io_req->xid, rrq_req->xid, refcount);
+
+	/* This should return the aborted io_req to the command pool */
+	if (orig_io_req)
+		kref_put(&orig_io_req->refcount, qedf_release_cmd);
+
+out_free:
+	kfree(cb_arg);
+}
+
+/* Assumes kref is already held by caller */
+int qedf_send_rrq(struct qedf_ioreq *aborted_io_req)
+{
+
+	struct fc_els_rrq rrq;
+	struct qedf_rport *fcport;
+	struct fc_lport *lport;
+	struct qedf_els_cb_arg *cb_arg = NULL;
+	struct qedf_ctx *qedf;
+	uint32_t sid;
+	uint32_t r_a_tov;
+	int rc;
+
+	if (!aborted_io_req) {
+		QEDF_ERR(NULL, "abort_io_req is NULL.\n");
+		return -EINVAL;
+	}
+
+	fcport = aborted_io_req->fcport;
+
+	/* Check that fcport is still offloaded */
+	if (!(test_bit(QEDF_RPORT_SESSION_READY, &fcport->flags))) {
+		QEDF_ERR(NULL, "fcport is no longer offloaded.\n");
+		return -EINVAL;
+	}
+
+	if (!fcport->qedf) {
+		QEDF_ERR(NULL, "fcport->qedf is NULL.\n");
+		return -EINVAL;
+	}
+
+	qedf = fcport->qedf;
+	lport = qedf->lport;
+	sid = fcport->sid;
+	r_a_tov = lport->r_a_tov;
+
+	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "Sending RRQ orig "
+		   "io = %p, orig_xid = 0x%x\n", aborted_io_req,
+		   aborted_io_req->xid);
+	memset(&rrq, 0, sizeof(rrq));
+
+	cb_arg = kzalloc(sizeof(struct qedf_els_cb_arg), GFP_NOIO);
+	if (!cb_arg) {
+		QEDF_ERR(&(qedf->dbg_ctx), "Unable to allocate cb_arg for "
+			  "RRQ\n");
+		rc = -ENOMEM;
+		goto rrq_err;
+	}
+
+	cb_arg->aborted_io_req = aborted_io_req;
+
+	rrq.rrq_cmd = ELS_RRQ;
+	hton24(rrq.rrq_s_id, sid);
+	rrq.rrq_ox_id = htons(aborted_io_req->xid);
+	rrq.rrq_rx_id =
+	    htons(aborted_io_req->task->tstorm_st_context.read_write.rx_id);
+
+	rc = qedf_initiate_els(fcport, ELS_RRQ, &rrq, sizeof(rrq),
+	    qedf_rrq_compl, cb_arg, r_a_tov);
+
+rrq_err:
+	if (rc) {
+		QEDF_ERR(&(qedf->dbg_ctx), "RRQ failed - release orig io "
+			  "req 0x%x\n", aborted_io_req->xid);
+		kfree(cb_arg);
+		kref_put(&aborted_io_req->refcount, qedf_release_cmd);
+	}
+	return rc;
+}
+
+static void qedf_process_l2_frame_compl(struct qedf_rport *fcport,
+					struct fc_frame *fp,
+					u16 l2_oxid)
+{
+	struct fc_lport *lport = fcport->qedf->lport;
+	struct fc_frame_header *fh;
+	u32 crc;
+
+	fh = (struct fc_frame_header *)fc_frame_header_get(fp);
+
+	/* Set the OXID we return to what libfc used */
+	if (l2_oxid != FC_XID_UNKNOWN)
+		fh->fh_ox_id = htons(l2_oxid);
+
+	/* Setup header fields */
+	fh->fh_r_ctl = FC_RCTL_ELS_REP;
+	fh->fh_type = FC_TYPE_ELS;
+	/* Last sequence, end sequence */
+	fh->fh_f_ctl[0] = 0x98;
+	hton24(fh->fh_d_id, lport->port_id);
+	hton24(fh->fh_s_id, fcport->rdata->ids.port_id);
+	fh->fh_rx_id = 0xffff;
+
+	/* Set frame attributes */
+	crc = fcoe_fc_crc(fp);
+	fc_frame_init(fp);
+	fr_dev(fp) = lport;
+	fr_sof(fp) = FC_SOF_I3;
+	fr_eof(fp) = FC_EOF_T;
+	fr_crc(fp) = cpu_to_le32(~crc);
+
+	/* Send completed request to libfc */
+	fc_exch_recv(lport, fp);
+}
+
+/*
+ * In instances where an ELS command times out we may need to restart the
+ * rport by logging out and then logging back in.
+ */
+void qedf_restart_rport(struct qedf_rport *fcport)
+{
+	struct fc_lport *lport;
+	struct fc_rport_priv *rdata;
+	u32 port_id;
+
+	if (!fcport)
+		return;
+
+	rdata = fcport->rdata;
+	if (rdata) {
+		lport = fcport->qedf->lport;
+		port_id = rdata->ids.port_id;
+		QEDF_ERR(&(fcport->qedf->dbg_ctx),
+		    "LOGO port_id=%x.\n", port_id);
+		fc_rport_logoff(rdata);
+		/* Recreate the rport and log back in */
+		rdata = fc_rport_create(lport, port_id);
+		if (rdata)
+			fc_rport_login(rdata);
+	}
+}
+
+static void qedf_l2_els_compl(struct qedf_els_cb_arg *cb_arg)
+{
+	struct qedf_ioreq *els_req;
+	struct qedf_rport *fcport;
+	struct qedf_mp_req *mp_req;
+	struct fc_frame *fp;
+	struct fc_frame_header *fh, *mp_fc_hdr;
+	void *resp_buf, *fc_payload;
+	u32 resp_len;
+	u16 l2_oxid;
+
+	l2_oxid = cb_arg->l2_oxid;
+	els_req = cb_arg->io_req;
+
+	if (!els_req) {
+		QEDF_ERR(NULL, "els_req is NULL.\n");
+		goto free_arg;
+	}
+
+	/*
+	 * If we are flushing the command just free the cb_arg as none of the
+	 * response data will be valid.
+	 */
+	if (els_req->event == QEDF_IOREQ_EV_ELS_FLUSH)
+		goto free_arg;
+
+	fcport = els_req->fcport;
+	mp_req = &(els_req->mp_req);
+	mp_fc_hdr = &(mp_req->resp_fc_hdr);
+	resp_len = mp_req->resp_len;
+	resp_buf = mp_req->resp_buf;
+
+	/*
+	 * If a middle path ELS command times out, don't try to return
+	 * the command but rather do any internal cleanup and then libfc
+	 * timeout the command and clean up its internal resources.
+	 */
+	if (els_req->event == QEDF_IOREQ_EV_ELS_TMO) {
+		/*
+		 * If ADISC times out, libfc will timeout the exchange and then
+		 * try to send a PLOGI which will timeout since the session is
+		 * still offloaded.  Force libfc to logout the session which
+		 * will offload the connection and allow the PLOGI response to
+		 * flow over the LL2 path.
+		 */
+		if (cb_arg->op == ELS_ADISC)
+			qedf_restart_rport(fcport);
+		return;
+	}
+
+	if (sizeof(struct fc_frame_header) + resp_len > QEDF_PAGE_SIZE) {
+		QEDF_ERR(&(fcport->qedf->dbg_ctx), "resp_len is "
+		   "beyond page size.\n");
+		goto free_arg;
+	}
+
+	fp = fc_frame_alloc(fcport->qedf->lport, resp_len);
+	if (!fp) {
+		QEDF_ERR(&(fcport->qedf->dbg_ctx),
+		    "fc_frame_alloc failure.\n");
+		return;
+	}
+
+	/* Copy frame header from firmware into fp */
+	fh = (struct fc_frame_header *)fc_frame_header_get(fp);
+	memcpy(fh, mp_fc_hdr, sizeof(struct fc_frame_header));
+
+	/* Copy payload from firmware into fp */
+	fc_payload = fc_frame_payload_get(fp, resp_len);
+	memcpy(fc_payload, resp_buf, resp_len);
+
+	QEDF_INFO(&(fcport->qedf->dbg_ctx), QEDF_LOG_ELS,
+	    "Completing OX_ID 0x%x back to libfc.\n", l2_oxid);
+	qedf_process_l2_frame_compl(fcport, fp, l2_oxid);
+
+free_arg:
+	kfree(cb_arg);
+}
+
+int qedf_send_adisc(struct qedf_rport *fcport, struct fc_frame *fp)
+{
+	struct fc_els_adisc *adisc;
+	struct fc_frame_header *fh;
+	struct fc_lport *lport = fcport->qedf->lport;
+	struct qedf_els_cb_arg *cb_arg = NULL;
+	struct qedf_ctx *qedf;
+	uint32_t r_a_tov = lport->r_a_tov;
+	int rc;
+
+	qedf = fcport->qedf;
+	fh = fc_frame_header_get(fp);
+
+	cb_arg = kzalloc(sizeof(struct qedf_els_cb_arg), GFP_NOIO);
+	if (!cb_arg) {
+		QEDF_ERR(&(qedf->dbg_ctx), "Unable to allocate cb_arg for "
+			  "ADISC\n");
+		rc = -ENOMEM;
+		goto adisc_err;
+	}
+	cb_arg->l2_oxid = ntohs(fh->fh_ox_id);
+
+	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
+	    "Sending ADISC ox_id=0x%x.\n", cb_arg->l2_oxid);
+
+	adisc = fc_frame_payload_get(fp, sizeof(*adisc));
+
+	rc = qedf_initiate_els(fcport, ELS_ADISC, adisc, sizeof(*adisc),
+	    qedf_l2_els_compl, cb_arg, r_a_tov);
+
+adisc_err:
+	if (rc) {
+		QEDF_ERR(&(qedf->dbg_ctx), "ADISC failed.\n");
+		kfree(cb_arg);
+	}
+	return rc;
+}
+
+static void qedf_srr_compl(struct qedf_els_cb_arg *cb_arg)
+{
+	struct qedf_ioreq *orig_io_req;
+	struct qedf_ioreq *srr_req;
+	struct qedf_mp_req *mp_req;
+	struct fc_frame_header *mp_fc_hdr, *fh;
+	struct fc_frame *fp;
+	void *resp_buf, *fc_payload;
+	u32 resp_len;
+	struct fc_lport *lport;
+	struct qedf_ctx *qedf;
+	int refcount;
+	u8 opcode;
+
+	srr_req = cb_arg->io_req;
+	qedf = srr_req->fcport->qedf;
+	lport = qedf->lport;
+
+	orig_io_req = cb_arg->aborted_io_req;
+
+	if (!orig_io_req)
+		goto out_free;
+
+	clear_bit(QEDF_CMD_SRR_SENT, &orig_io_req->flags);
+
+	if (srr_req->event != QEDF_IOREQ_EV_ELS_TMO &&
+	    srr_req->event != QEDF_IOREQ_EV_ELS_ERR_DETECT)
+		cancel_delayed_work_sync(&orig_io_req->timeout_work);
+
+	refcount = atomic_read(&orig_io_req->refcount.refcount);
+	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "Entered: orig_io=%p,"
+		   " orig_io_xid=0x%x, rec_xid=0x%x, refcount=%d\n",
+		   orig_io_req, orig_io_req->xid, srr_req->xid, refcount);
+
+	/* If a SRR times out, simply free resources */
+	if (srr_req->event == QEDF_IOREQ_EV_ELS_TMO)
+		goto out_free;
+
+	/* Normalize response data into struct fc_frame */
+	mp_req = &(srr_req->mp_req);
+	mp_fc_hdr = &(mp_req->resp_fc_hdr);
+	resp_len = mp_req->resp_len;
+	resp_buf = mp_req->resp_buf;
+
+	fp = fc_frame_alloc(lport, resp_len);
+	if (!fp) {
+		QEDF_ERR(&(qedf->dbg_ctx),
+		    "fc_frame_alloc failure.\n");
+		goto out_free;
+	}
+
+	/* Copy frame header from firmware into fp */
+	fh = (struct fc_frame_header *)fc_frame_header_get(fp);
+	memcpy(fh, mp_fc_hdr, sizeof(struct fc_frame_header));
+
+	/* Copy payload from firmware into fp */
+	fc_payload = fc_frame_payload_get(fp, resp_len);
+	memcpy(fc_payload, resp_buf, resp_len);
+
+	opcode = fc_frame_payload_op(fp);
+	switch (opcode) {
+	case ELS_LS_ACC:
+		QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
+		    "SRR success.\n");
+		break;
+	case ELS_LS_RJT:
+		QEDF_INFO(&qedf->dbg_ctx, QEDF_LOG_ELS,
+		    "SRR rejected.\n");
+		qedf_initiate_abts(orig_io_req, true);
+		break;
+	}
+
+	fc_frame_free(fp);
+out_free:
+	/* Put reference for original command since SRR completed */
+	kref_put(&orig_io_req->refcount, qedf_release_cmd);
+	kfree(cb_arg);
+}
+
+static int qedf_send_srr(struct qedf_ioreq *orig_io_req, u32 offset, u8 r_ctl)
+{
+	struct fcp_srr srr;
+	struct qedf_ctx *qedf;
+	struct qedf_rport *fcport;
+	struct fc_lport *lport;
+	struct qedf_els_cb_arg *cb_arg = NULL;
+	u32 sid, r_a_tov;
+	int rc;
+
+	if (!orig_io_req) {
+		QEDF_ERR(NULL, "orig_io_req is NULL.\n");
+		return -EINVAL;
+	}
+
+	fcport = orig_io_req->fcport;
+
+	/* Check that fcport is still offloaded */
+	if (!(test_bit(QEDF_RPORT_SESSION_READY, &fcport->flags))) {
+		QEDF_ERR(NULL, "fcport is no longer offloaded.\n");
+		return -EINVAL;
+	}
+
+	if (!fcport->qedf) {
+		QEDF_ERR(NULL, "fcport->qedf is NULL.\n");
+		return -EINVAL;
+	}
+
+	/* Take reference until SRR command completion */
+	kref_get(&orig_io_req->refcount);
+
+	qedf = fcport->qedf;
+	lport = qedf->lport;
+	sid = fcport->sid;
+	r_a_tov = lport->r_a_tov;
+
+	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "Sending SRR orig_io=%p, "
+		   "orig_xid=0x%x\n", orig_io_req, orig_io_req->xid);
+	memset(&srr, 0, sizeof(srr));
+
+	cb_arg = kzalloc(sizeof(struct qedf_els_cb_arg), GFP_NOIO);
+	if (!cb_arg) {
+		QEDF_ERR(&(qedf->dbg_ctx), "Unable to allocate cb_arg for "
+			  "SRR\n");
+		rc = -ENOMEM;
+		goto srr_err;
+	}
+
+	cb_arg->aborted_io_req = orig_io_req;
+
+	srr.srr_op = ELS_SRR;
+	srr.srr_ox_id = htons(orig_io_req->xid);
+	srr.srr_rx_id = htons(orig_io_req->rx_id);
+	srr.srr_rel_off = htonl(offset);
+	srr.srr_r_ctl = r_ctl;
+
+	rc = qedf_initiate_els(fcport, ELS_SRR, &srr, sizeof(srr),
+	    qedf_srr_compl, cb_arg, r_a_tov);
+
+srr_err:
+	if (rc) {
+		QEDF_ERR(&(qedf->dbg_ctx), "SRR failed - release orig_io_req"
+			  "=0x%x\n", orig_io_req->xid);
+		kfree(cb_arg);
+		/* If we fail to queue SRR, send ABTS to orig_io */
+		qedf_initiate_abts(orig_io_req, true);
+		kref_put(&orig_io_req->refcount, qedf_release_cmd);
+	} else
+		/* Tell other threads that SRR is in progress */
+		set_bit(QEDF_CMD_SRR_SENT, &orig_io_req->flags);
+
+	return rc;
+}
+
+static void qedf_initiate_seq_cleanup(struct qedf_ioreq *orig_io_req,
+	u32 offset, u8 r_ctl)
+{
+	struct qedf_rport *fcport;
+	unsigned long flags;
+	struct qedf_els_cb_arg *cb_arg;
+
+	fcport = orig_io_req->fcport;
+
+	QEDF_INFO(&(fcport->qedf->dbg_ctx), QEDF_LOG_ELS,
+	    "Doing sequence cleanup for xid=0x%x offset=%u.\n",
+	    orig_io_req->xid, offset);
+
+	cb_arg = kzalloc(sizeof(struct qedf_els_cb_arg), GFP_NOIO);
+	if (!cb_arg) {
+		QEDF_ERR(&(fcport->qedf->dbg_ctx), "Unable to allocate cb_arg "
+			  "for sequence cleanup\n");
+		return;
+	}
+
+	/* Get reference for cleanup request */
+	kref_get(&orig_io_req->refcount);
+
+	orig_io_req->cmd_type = QEDF_SEQ_CLEANUP;
+	cb_arg->offset = offset;
+	cb_arg->r_ctl = r_ctl;
+	orig_io_req->cb_arg = cb_arg;
+
+	qedf_cmd_timer_set(fcport->qedf, orig_io_req,
+	    QEDF_CLEANUP_TIMEOUT * HZ);
+
+	spin_lock_irqsave(&fcport->rport_lock, flags);
+
+	qedf_add_to_sq(fcport, orig_io_req->xid, 0,
+	    FCOE_TASK_TYPE_SEQUENCE_CLEANUP, offset);
+	qedf_ring_doorbell(fcport);
+
+	spin_unlock_irqrestore(&fcport->rport_lock, flags);
+}
+
+void qedf_process_seq_cleanup_compl(struct qedf_ctx *qedf,
+	struct fcoe_cqe *cqe, struct qedf_ioreq *io_req)
+{
+	int rc;
+	struct qedf_els_cb_arg *cb_arg;
+
+	cb_arg = io_req->cb_arg;
+
+	/* If we timed out just free resources */
+	if (io_req->event == QEDF_IOREQ_EV_ELS_TMO || !cqe)
+		goto free;
+
+	/* Kill the timer we put on the request */
+	cancel_delayed_work_sync(&io_req->timeout_work);
+
+	rc = qedf_send_srr(io_req, cb_arg->offset, cb_arg->r_ctl);
+	if (rc)
+		QEDF_ERR(&(qedf->dbg_ctx), "Unable to send SRR, I/O will "
+		    "abort, xid=0x%x.\n", io_req->xid);
+free:
+	kfree(cb_arg);
+	kref_put(&io_req->refcount, qedf_release_cmd);
+}
+
+static bool qedf_requeue_io_req(struct qedf_ioreq *orig_io_req)
+{
+	struct qedf_rport *fcport;
+	struct qedf_ioreq *new_io_req;
+	unsigned long flags;
+	bool rc = false;
+
+	fcport = orig_io_req->fcport;
+	if (!fcport) {
+		QEDF_ERR(NULL, "fcport is NULL.\n");
+		goto out;
+	}
+
+	if (!orig_io_req->sc_cmd) {
+		QEDF_ERR(&(fcport->qedf->dbg_ctx), "sc_cmd is NULL for "
+		    "xid=0x%x.\n", orig_io_req->xid);
+		goto out;
+	}
+
+	new_io_req = qedf_alloc_cmd(fcport, QEDF_SCSI_CMD);
+	if (!new_io_req) {
+		QEDF_ERR(&(fcport->qedf->dbg_ctx), "Could not allocate new "
+		    "io_req.\n");
+		goto out;
+	}
+
+	new_io_req->sc_cmd = orig_io_req->sc_cmd;
+
+	/*
+	 * This keeps the sc_cmd struct from being returned to the tape
+	 * driver and being requeued twice. We do need to put a reference
+	 * for the original I/O request since we will not do a SCSI completion
+	 * for it.
+	 */
+	orig_io_req->sc_cmd = NULL;
+	kref_put(&orig_io_req->refcount, qedf_release_cmd);
+
+	spin_lock_irqsave(&fcport->rport_lock, flags);
+
+	/* kref for new command released in qedf_post_io_req on error */
+	if (qedf_post_io_req(fcport, new_io_req)) {
+		QEDF_ERR(&(fcport->qedf->dbg_ctx), "Unable to post io_req\n");
+		/* Return SQE to pool */
+		atomic_inc(&fcport->free_sqes);
+	} else {
+		QEDF_INFO(&(fcport->qedf->dbg_ctx), QEDF_LOG_ELS,
+		    "Reissued SCSI command from  orig_xid=0x%x on "
+		    "new_xid=0x%x.\n", orig_io_req->xid, new_io_req->xid);
+		/*
+		 * Abort the original I/O but do not return SCSI command as
+		 * it has been reissued on another OX_ID.
+		 */
+		spin_unlock_irqrestore(&fcport->rport_lock, flags);
+		qedf_initiate_abts(orig_io_req, false);
+		goto out;
+	}
+
+	spin_unlock_irqrestore(&fcport->rport_lock, flags);
+out:
+	return rc;
+}
+
+
+static void qedf_rec_compl(struct qedf_els_cb_arg *cb_arg)
+{
+	struct qedf_ioreq *orig_io_req;
+	struct qedf_ioreq *rec_req;
+	struct qedf_mp_req *mp_req;
+	struct fc_frame_header *mp_fc_hdr, *fh;
+	struct fc_frame *fp;
+	void *resp_buf, *fc_payload;
+	u32 resp_len;
+	struct fc_lport *lport;
+	struct qedf_ctx *qedf;
+	int refcount;
+	enum fc_rctl r_ctl;
+	struct fc_els_ls_rjt *rjt;
+	struct fc_els_rec_acc *acc;
+	u8 opcode;
+	u32 offset, e_stat;
+	struct scsi_cmnd *sc_cmd;
+	bool srr_needed = false;
+
+	rec_req = cb_arg->io_req;
+	qedf = rec_req->fcport->qedf;
+	lport = qedf->lport;
+
+	orig_io_req = cb_arg->aborted_io_req;
+
+	if (!orig_io_req)
+		goto out_free;
+
+	if (rec_req->event != QEDF_IOREQ_EV_ELS_TMO &&
+	    rec_req->event != QEDF_IOREQ_EV_ELS_ERR_DETECT)
+		cancel_delayed_work_sync(&orig_io_req->timeout_work);
+
+	refcount = atomic_read(&orig_io_req->refcount.refcount);
+	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "Entered: orig_io=%p,"
+		   " orig_io_xid=0x%x, rec_xid=0x%x, refcount=%d\n",
+		   orig_io_req, orig_io_req->xid, rec_req->xid, refcount);
+
+	/* If a REC times out, free resources */
+	if (rec_req->event == QEDF_IOREQ_EV_ELS_TMO)
+		goto out_free;
+
+	/* Normalize response data into struct fc_frame */
+	mp_req = &(rec_req->mp_req);
+	mp_fc_hdr = &(mp_req->resp_fc_hdr);
+	resp_len = mp_req->resp_len;
+	acc = resp_buf = mp_req->resp_buf;
+
+	fp = fc_frame_alloc(lport, resp_len);
+	if (!fp) {
+		QEDF_ERR(&(qedf->dbg_ctx),
+		    "fc_frame_alloc failure.\n");
+		goto out_free;
+	}
+
+	/* Copy frame header from firmware into fp */
+	fh = (struct fc_frame_header *)fc_frame_header_get(fp);
+	memcpy(fh, mp_fc_hdr, sizeof(struct fc_frame_header));
+
+	/* Copy payload from firmware into fp */
+	fc_payload = fc_frame_payload_get(fp, resp_len);
+	memcpy(fc_payload, resp_buf, resp_len);
+
+	opcode = fc_frame_payload_op(fp);
+	if (opcode == ELS_LS_RJT) {
+		rjt = fc_frame_payload_get(fp, sizeof(*rjt));
+		QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
+		    "Received LS_RJT for REC: er_reason=0x%x, "
+		    "er_explan=0x%x.\n", rjt->er_reason, rjt->er_explan);
+		/*
+		 * The following response(s) mean that we need to reissue the
+		 * request on another exchange.  We need to do this without
+		 * informing the upper layers lest it cause an application
+		 * error.
+		 */
+		if ((rjt->er_reason == ELS_RJT_LOGIC ||
+		    rjt->er_reason == ELS_RJT_UNAB) &&
+		    rjt->er_explan == ELS_EXPL_OXID_RXID) {
+			QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
+			    "Handle CMD LOST case.\n");
+			qedf_requeue_io_req(orig_io_req);
+		}
+	} else if (opcode == ELS_LS_ACC) {
+		offset = ntohl(acc->reca_fc4value);
+		e_stat = ntohl(acc->reca_e_stat);
+		QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
+		    "Received LS_ACC for REC: offset=0x%x, e_stat=0x%x.\n",
+		    offset, e_stat);
+		if (e_stat & ESB_ST_SEQ_INIT)  {
+			QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
+			    "Target has the seq init\n");
+			goto out_free_frame;
+		}
+		sc_cmd = orig_io_req->sc_cmd;
+		if (!sc_cmd) {
+			QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
+			    "sc_cmd is NULL for xid=0x%x.\n",
+			    orig_io_req->xid);
+			goto out_free_frame;
+		}
+		/* SCSI write case */
+		if (sc_cmd->sc_data_direction == DMA_TO_DEVICE) {
+			if (offset == orig_io_req->data_xfer_len) {
+				QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
+				    "WRITE - response lost.\n");
+				r_ctl = FC_RCTL_DD_CMD_STATUS;
+				srr_needed = true;
+				offset = 0;
+			} else {
+				QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
+				    "WRITE - XFER_RDY/DATA lost.\n");
+				r_ctl = FC_RCTL_DD_DATA_DESC;
+				/* Use data from warning CQE instead of REC */
+				offset = orig_io_req->tx_buf_off;
+			}
+		/* SCSI read case */
+		} else {
+			if (orig_io_req->rx_buf_off ==
+			    orig_io_req->data_xfer_len) {
+				QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
+				    "READ - response lost.\n");
+				srr_needed = true;
+				r_ctl = FC_RCTL_DD_CMD_STATUS;
+				offset = 0;
+			} else {
+				QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
+				    "READ - DATA lost.\n");
+				/*
+				 * For read case we always set the offset to 0
+				 * for sequence recovery task.
+				 */
+				offset = 0;
+				r_ctl = FC_RCTL_DD_SOL_DATA;
+			}
+		}
+
+		if (srr_needed)
+			qedf_send_srr(orig_io_req, offset, r_ctl);
+		else
+			qedf_initiate_seq_cleanup(orig_io_req, offset, r_ctl);
+	}
+
+out_free_frame:
+	fc_frame_free(fp);
+out_free:
+	/* Put reference for original command since REC completed */
+	kref_put(&orig_io_req->refcount, qedf_release_cmd);
+	kfree(cb_arg);
+}
+
+/* Assumes kref is already held by caller */
+int qedf_send_rec(struct qedf_ioreq *orig_io_req)
+{
+
+	struct fc_els_rec rec;
+	struct qedf_rport *fcport;
+	struct fc_lport *lport;
+	struct qedf_els_cb_arg *cb_arg = NULL;
+	struct qedf_ctx *qedf;
+	uint32_t sid;
+	uint32_t r_a_tov;
+	int rc;
+
+	if (!orig_io_req) {
+		QEDF_ERR(NULL, "orig_io_req is NULL.\n");
+		return -EINVAL;
+	}
+
+	fcport = orig_io_req->fcport;
+
+	/* Check that fcport is still offloaded */
+	if (!test_bit(QEDF_RPORT_SESSION_READY, &fcport->flags)) {
+		QEDF_ERR(NULL, "fcport is no longer offloaded.\n");
+		return -EINVAL;
+	}
+
+	if (!fcport->qedf) {
+		QEDF_ERR(NULL, "fcport->qedf is NULL.\n");
+		return -EINVAL;
+	}
+
+	/* Take reference until REC command completion */
+	kref_get(&orig_io_req->refcount);
+
+	qedf = fcport->qedf;
+	lport = qedf->lport;
+	sid = fcport->sid;
+	r_a_tov = lport->r_a_tov;
+
+	memset(&rec, 0, sizeof(rec));
+
+	cb_arg = kzalloc(sizeof(struct qedf_els_cb_arg), GFP_NOIO);
+	if (!cb_arg) {
+		QEDF_ERR(&(qedf->dbg_ctx), "Unable to allocate cb_arg for "
+			  "REC\n");
+		rc = -ENOMEM;
+		goto rec_err;
+	}
+
+	cb_arg->aborted_io_req = orig_io_req;
+
+	rec.rec_cmd = ELS_REC;
+	hton24(rec.rec_s_id, sid);
+	rec.rec_ox_id = htons(orig_io_req->xid);
+	rec.rec_rx_id =
+	    htons(orig_io_req->task->tstorm_st_context.read_write.rx_id);
+
+	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "Sending REC orig_io=%p, "
+	   "orig_xid=0x%x rx_id=0x%x\n", orig_io_req,
+	   orig_io_req->xid, rec.rec_rx_id);
+	rc = qedf_initiate_els(fcport, ELS_REC, &rec, sizeof(rec),
+	    qedf_rec_compl, cb_arg, r_a_tov);
+
+rec_err:
+	if (rc) {
+		QEDF_ERR(&(qedf->dbg_ctx), "REC failed - release orig_io_req"
+			  "=0x%x\n", orig_io_req->xid);
+		kfree(cb_arg);
+		kref_put(&orig_io_req->refcount, qedf_release_cmd);
+	}
+	return rc;
+}