Patchwork [v6,7/8] csiostor: Chelsio FCoE offload driver submission (sources part 4).

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Submitter Naresh Kumar Inna
Date Nov. 15, 2012, 5:11 p.m.
Message ID <1352999484-17812-8-git-send-email-naresh@chelsio.com>
Download mbox | patch
Permalink /patch/199259/
State Not Applicable
Delegated to: David Miller
Headers show

Comments

Naresh Kumar Inna - Nov. 15, 2012, 5:11 p.m.
This patch contains code to implement the interrupt handling and the fast
path I/O functionality. The interrupt handling includes allocation of
MSIX vectors, registering and implemeting the interrupt service routines.
The fast path I/O functionality includes posting the I/O request to firmware
via Work Requests, tracking/completing them, and handling task management
requests. SCSI midlayer host template implementation is also covered by
this patch.

Signed-off-by: Naresh Kumar Inna <naresh@chelsio.com>
---
V2:
- Inlined code instead of macro in csio_isr.c
- Use true/false instead if CSIO_TRUE/CSIO_FALSE.
- Use DMA_ defines instead of CSIO_IOREQF_DMA_ defines.
- Replaced large local stack buffer with pre-allocated memory.
- Replaced fast path macros with static functions.
- Removed extra empty lines, needless comment.

V4: Removed needless header file inclusion.

V5:
- Changed over to lockless queuecommand.
- Removed needless header inclusion.
- Re-wrote error paths to reduce lock/unlock ambiguity.

 drivers/scsi/csiostor/csio_isr.c  |  624 +++++++++
 drivers/scsi/csiostor/csio_scsi.c | 2555 +++++++++++++++++++++++++++++++++++++
 2 files changed, 3179 insertions(+), 0 deletions(-)
 create mode 100644 drivers/scsi/csiostor/csio_isr.c
 create mode 100644 drivers/scsi/csiostor/csio_scsi.c

Patch

diff --git a/drivers/scsi/csiostor/csio_isr.c b/drivers/scsi/csiostor/csio_isr.c
new file mode 100644
index 0000000..7ee9777
--- /dev/null
+++ b/drivers/scsi/csiostor/csio_isr.c
@@ -0,0 +1,624 @@ 
+/*
+ * This file is part of the Chelsio FCoE driver for Linux.
+ *
+ * Copyright (c) 2008-2012 Chelsio Communications, Inc. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/interrupt.h>
+#include <linux/cpumask.h>
+#include <linux/string.h>
+
+#include "csio_init.h"
+#include "csio_hw.h"
+
+static irqreturn_t
+csio_nondata_isr(int irq, void *dev_id)
+{
+	struct csio_hw *hw = (struct csio_hw *) dev_id;
+	int rv;
+	unsigned long flags;
+
+	if (unlikely(!hw))
+		return IRQ_NONE;
+
+	if (unlikely(pci_channel_offline(hw->pdev))) {
+		CSIO_INC_STATS(hw, n_pcich_offline);
+		return IRQ_NONE;
+	}
+
+	spin_lock_irqsave(&hw->lock, flags);
+	csio_hw_slow_intr_handler(hw);
+	rv = csio_mb_isr_handler(hw);
+
+	if (rv == 0 && !(hw->flags & CSIO_HWF_FWEVT_PENDING)) {
+		hw->flags |= CSIO_HWF_FWEVT_PENDING;
+		spin_unlock_irqrestore(&hw->lock, flags);
+		schedule_work(&hw->evtq_work);
+		return IRQ_HANDLED;
+	}
+	spin_unlock_irqrestore(&hw->lock, flags);
+	return IRQ_HANDLED;
+}
+
+/*
+ * csio_fwevt_handler - Common FW event handler routine.
+ * @hw: HW module.
+ *
+ * This is the ISR for FW events. It is shared b/w MSIX
+ * and INTx handlers.
+ */
+static void
+csio_fwevt_handler(struct csio_hw *hw)
+{
+	int rv;
+	unsigned long flags;
+
+	rv = csio_fwevtq_handler(hw);
+
+	spin_lock_irqsave(&hw->lock, flags);
+	if (rv == 0 && !(hw->flags & CSIO_HWF_FWEVT_PENDING)) {
+		hw->flags |= CSIO_HWF_FWEVT_PENDING;
+		spin_unlock_irqrestore(&hw->lock, flags);
+		schedule_work(&hw->evtq_work);
+		return;
+	}
+	spin_unlock_irqrestore(&hw->lock, flags);
+
+} /* csio_fwevt_handler */
+
+/*
+ * csio_fwevt_isr() - FW events MSIX ISR
+ * @irq:
+ * @dev_id:
+ *
+ * Process WRs on the FW event queue.
+ *
+ */
+static irqreturn_t
+csio_fwevt_isr(int irq, void *dev_id)
+{
+	struct csio_hw *hw = (struct csio_hw *) dev_id;
+
+	if (unlikely(!hw))
+		return IRQ_NONE;
+
+	if (unlikely(pci_channel_offline(hw->pdev))) {
+		CSIO_INC_STATS(hw, n_pcich_offline);
+		return IRQ_NONE;
+	}
+
+	csio_fwevt_handler(hw);
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * csio_fwevt_isr() - INTx wrapper for handling FW events.
+ * @irq:
+ * @dev_id:
+ */
+void
+csio_fwevt_intx_handler(struct csio_hw *hw, void *wr, uint32_t len,
+			   struct csio_fl_dma_buf *flb, void *priv)
+{
+	csio_fwevt_handler(hw);
+} /* csio_fwevt_intx_handler */
+
+/*
+ * csio_process_scsi_cmpl - Process a SCSI WR completion.
+ * @hw: HW module.
+ * @wr: The completed WR from the ingress queue.
+ * @len: Length of the WR.
+ * @flb: Freelist buffer array.
+ *
+ */
+static void
+csio_process_scsi_cmpl(struct csio_hw *hw, void *wr, uint32_t len,
+			struct csio_fl_dma_buf *flb, void *cbfn_q)
+{
+	struct csio_ioreq *ioreq;
+	uint8_t *scsiwr;
+	uint8_t subop;
+	void *cmnd;
+	unsigned long flags;
+
+	ioreq = csio_scsi_cmpl_handler(hw, wr, len, flb, NULL, &scsiwr);
+	if (likely(ioreq)) {
+		if (unlikely(*scsiwr == FW_SCSI_ABRT_CLS_WR)) {
+			subop = FW_SCSI_ABRT_CLS_WR_SUB_OPCODE_GET(
+					((struct fw_scsi_abrt_cls_wr *)
+					    scsiwr)->sub_opcode_to_chk_all_io);
+
+			csio_dbg(hw, "%s cmpl recvd ioreq:%p status:%d\n",
+				    subop ? "Close" : "Abort",
+				    ioreq, ioreq->wr_status);
+
+			spin_lock_irqsave(&hw->lock, flags);
+			if (subop)
+				csio_scsi_closed(ioreq,
+						 (struct list_head *)cbfn_q);
+			else
+				csio_scsi_aborted(ioreq,
+						  (struct list_head *)cbfn_q);
+			/*
+			 * We call scsi_done for I/Os that driver thinks aborts
+			 * have timed out. If there is a race caused by FW
+			 * completing abort at the exact same time that the
+			 * driver has deteced the abort timeout, the following
+			 * check prevents calling of scsi_done twice for the
+			 * same command: once from the eh_abort_handler, another
+			 * from csio_scsi_isr_handler(). This also avoids the
+			 * need to check if csio_scsi_cmnd(req) is NULL in the
+			 * fast path.
+			 */
+			cmnd = csio_scsi_cmnd(ioreq);
+			if (unlikely(cmnd == NULL))
+				list_del_init(&ioreq->sm.sm_list);
+
+			spin_unlock_irqrestore(&hw->lock, flags);
+
+			if (unlikely(cmnd == NULL))
+				csio_put_scsi_ioreq_lock(hw,
+						csio_hw_to_scsim(hw), ioreq);
+		} else {
+			spin_lock_irqsave(&hw->lock, flags);
+			csio_scsi_completed(ioreq, (struct list_head *)cbfn_q);
+			spin_unlock_irqrestore(&hw->lock, flags);
+		}
+	}
+}
+
+/*
+ * csio_scsi_isr_handler() - Common SCSI ISR handler.
+ * @iq: Ingress queue pointer.
+ *
+ * Processes SCSI completions on the SCSI IQ indicated by scm->iq_idx
+ * by calling csio_wr_process_iq_idx. If there are completions on the
+ * isr_cbfn_q, yank them out into a local queue and call their io_cbfns.
+ * Once done, add these completions onto the freelist.
+ * This routine is shared b/w MSIX and INTx.
+ */
+static inline irqreturn_t
+csio_scsi_isr_handler(struct csio_q *iq)
+{
+	struct csio_hw *hw = (struct csio_hw *)iq->owner;
+	LIST_HEAD(cbfn_q);
+	struct list_head *tmp;
+	struct csio_scsim *scm;
+	struct csio_ioreq *ioreq;
+	int isr_completions = 0;
+
+	scm = csio_hw_to_scsim(hw);
+
+	if (unlikely(csio_wr_process_iq(hw, iq, csio_process_scsi_cmpl,
+					&cbfn_q) != 0))
+		return IRQ_NONE;
+
+	/* Call back the completion routines */
+	list_for_each(tmp, &cbfn_q) {
+		ioreq = (struct csio_ioreq *)tmp;
+		isr_completions++;
+		ioreq->io_cbfn(hw, ioreq);
+		/* Release ddp buffer if used for this req */
+		if (unlikely(ioreq->dcopy))
+			csio_put_scsi_ddp_list_lock(hw, scm, &ioreq->gen_list,
+						    ioreq->nsge);
+	}
+
+	if (isr_completions) {
+		/* Return the ioreqs back to ioreq->freelist */
+		csio_put_scsi_ioreq_list_lock(hw, scm, &cbfn_q,
+					      isr_completions);
+	}
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * csio_scsi_isr() - SCSI MSIX handler
+ * @irq:
+ * @dev_id:
+ *
+ * This is the top level SCSI MSIX handler. Calls csio_scsi_isr_handler()
+ * for handling SCSI completions.
+ */
+static irqreturn_t
+csio_scsi_isr(int irq, void *dev_id)
+{
+	struct csio_q *iq = (struct csio_q *) dev_id;
+	struct csio_hw *hw;
+
+	if (unlikely(!iq))
+		return IRQ_NONE;
+
+	hw = (struct csio_hw *)iq->owner;
+
+	if (unlikely(pci_channel_offline(hw->pdev))) {
+		CSIO_INC_STATS(hw, n_pcich_offline);
+		return IRQ_NONE;
+	}
+
+	csio_scsi_isr_handler(iq);
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * csio_scsi_intx_handler() - SCSI INTx handler
+ * @irq:
+ * @dev_id:
+ *
+ * This is the top level SCSI INTx handler. Calls csio_scsi_isr_handler()
+ * for handling SCSI completions.
+ */
+void
+csio_scsi_intx_handler(struct csio_hw *hw, void *wr, uint32_t len,
+			struct csio_fl_dma_buf *flb, void *priv)
+{
+	struct csio_q *iq = priv;
+
+	csio_scsi_isr_handler(iq);
+
+} /* csio_scsi_intx_handler */
+
+/*
+ * csio_fcoe_isr() - INTx/MSI interrupt service routine for FCoE.
+ * @irq:
+ * @dev_id:
+ *
+ *
+ */
+static irqreturn_t
+csio_fcoe_isr(int irq, void *dev_id)
+{
+	struct csio_hw *hw = (struct csio_hw *) dev_id;
+	struct csio_q *intx_q = NULL;
+	int rv;
+	irqreturn_t ret = IRQ_NONE;
+	unsigned long flags;
+
+	if (unlikely(!hw))
+		return IRQ_NONE;
+
+	if (unlikely(pci_channel_offline(hw->pdev))) {
+		CSIO_INC_STATS(hw, n_pcich_offline);
+		return IRQ_NONE;
+	}
+
+	/* Disable the interrupt for this PCI function. */
+	if (hw->intr_mode == CSIO_IM_INTX)
+		csio_wr_reg32(hw, 0, MYPF_REG(PCIE_PF_CLI));
+
+	/*
+	 * The read in the following function will flush the
+	 * above write.
+	 */
+	if (csio_hw_slow_intr_handler(hw))
+		ret = IRQ_HANDLED;
+
+	/* Get the INTx Forward interrupt IQ. */
+	intx_q = csio_get_q(hw, hw->intr_iq_idx);
+
+	CSIO_DB_ASSERT(intx_q);
+
+	/* IQ handler is not possible for intx_q, hence pass in NULL */
+	if (likely(csio_wr_process_iq(hw, intx_q, NULL, NULL) == 0))
+		ret = IRQ_HANDLED;
+
+	spin_lock_irqsave(&hw->lock, flags);
+	rv = csio_mb_isr_handler(hw);
+	if (rv == 0 && !(hw->flags & CSIO_HWF_FWEVT_PENDING)) {
+		hw->flags |= CSIO_HWF_FWEVT_PENDING;
+		spin_unlock_irqrestore(&hw->lock, flags);
+		schedule_work(&hw->evtq_work);
+		return IRQ_HANDLED;
+	}
+	spin_unlock_irqrestore(&hw->lock, flags);
+
+	return ret;
+}
+
+static void
+csio_add_msix_desc(struct csio_hw *hw)
+{
+	int i;
+	struct csio_msix_entries *entryp = &hw->msix_entries[0];
+	int k = CSIO_EXTRA_VECS;
+	int len = sizeof(entryp->desc) - 1;
+	int cnt = hw->num_sqsets + k;
+
+	/* Non-data vector */
+	memset(entryp->desc, 0, len + 1);
+	snprintf(entryp->desc, len, "csio-%02x:%02x:%x-nondata",
+		 CSIO_PCI_BUS(hw), CSIO_PCI_DEV(hw), CSIO_PCI_FUNC(hw));
+
+	entryp++;
+	memset(entryp->desc, 0, len + 1);
+	snprintf(entryp->desc, len, "csio-%02x:%02x:%x-fwevt",
+		 CSIO_PCI_BUS(hw), CSIO_PCI_DEV(hw), CSIO_PCI_FUNC(hw));
+	entryp++;
+
+	/* Name SCSI vecs */
+	for (i = k; i < cnt; i++, entryp++) {
+		memset(entryp->desc, 0, len + 1);
+		snprintf(entryp->desc, len, "csio-%02x:%02x:%x-scsi%d",
+			 CSIO_PCI_BUS(hw), CSIO_PCI_DEV(hw),
+			 CSIO_PCI_FUNC(hw), i - CSIO_EXTRA_VECS);
+	}
+}
+
+int
+csio_request_irqs(struct csio_hw *hw)
+{
+	int rv, i, j, k = 0;
+	struct csio_msix_entries *entryp = &hw->msix_entries[0];
+	struct csio_scsi_cpu_info *info;
+
+	if (hw->intr_mode != CSIO_IM_MSIX) {
+		rv = request_irq(hw->pdev->irq, csio_fcoe_isr,
+					(hw->intr_mode == CSIO_IM_MSI) ?
+							0 : IRQF_SHARED,
+					KBUILD_MODNAME, hw);
+		if (rv) {
+			if (hw->intr_mode == CSIO_IM_MSI)
+				pci_disable_msi(hw->pdev);
+			csio_err(hw, "Failed to allocate interrupt line.\n");
+			return -EINVAL;
+		}
+
+		goto out;
+	}
+
+	/* Add the MSIX vector descriptions */
+	csio_add_msix_desc(hw);
+
+	rv = request_irq(entryp[k].vector, csio_nondata_isr, 0,
+			 entryp[k].desc, hw);
+	if (rv) {
+		csio_err(hw, "IRQ request failed for vec %d err:%d\n",
+			 entryp[k].vector, rv);
+		goto err;
+	}
+
+	entryp[k++].dev_id = (void *)hw;
+
+	rv = request_irq(entryp[k].vector, csio_fwevt_isr, 0,
+			 entryp[k].desc, hw);
+	if (rv) {
+		csio_err(hw, "IRQ request failed for vec %d err:%d\n",
+			 entryp[k].vector, rv);
+		goto err;
+	}
+
+	entryp[k++].dev_id = (void *)hw;
+
+	/* Allocate IRQs for SCSI */
+	for (i = 0; i < hw->num_pports; i++) {
+		info = &hw->scsi_cpu_info[i];
+		for (j = 0; j < info->max_cpus; j++, k++) {
+			struct csio_scsi_qset *sqset = &hw->sqset[i][j];
+			struct csio_q *q = hw->wrm.q_arr[sqset->iq_idx];
+
+			rv = request_irq(entryp[k].vector, csio_scsi_isr, 0,
+					 entryp[k].desc, q);
+			if (rv) {
+				csio_err(hw,
+				       "IRQ request failed for vec %d err:%d\n",
+				       entryp[k].vector, rv);
+				goto err;
+			}
+
+			entryp[k].dev_id = (void *)q;
+
+		} /* for all scsi cpus */
+	} /* for all ports */
+
+out:
+	hw->flags |= CSIO_HWF_HOST_INTR_ENABLED;
+
+	return 0;
+
+err:
+	for (i = 0; i < k; i++) {
+		entryp = &hw->msix_entries[i];
+		free_irq(entryp->vector, entryp->dev_id);
+	}
+	pci_disable_msix(hw->pdev);
+
+	return -EINVAL;
+}
+
+static void
+csio_disable_msix(struct csio_hw *hw, bool free)
+{
+	int i;
+	struct csio_msix_entries *entryp;
+	int cnt = hw->num_sqsets + CSIO_EXTRA_VECS;
+
+	if (free) {
+		for (i = 0; i < cnt; i++) {
+			entryp = &hw->msix_entries[i];
+			free_irq(entryp->vector, entryp->dev_id);
+		}
+	}
+	pci_disable_msix(hw->pdev);
+}
+
+/* Reduce per-port max possible CPUs */
+static void
+csio_reduce_sqsets(struct csio_hw *hw, int cnt)
+{
+	int i;
+	struct csio_scsi_cpu_info *info;
+
+	while (cnt < hw->num_sqsets) {
+		for (i = 0; i < hw->num_pports; i++) {
+			info = &hw->scsi_cpu_info[i];
+			if (info->max_cpus > 1) {
+				info->max_cpus--;
+				hw->num_sqsets--;
+				if (hw->num_sqsets <= cnt)
+					break;
+			}
+		}
+	}
+
+	csio_dbg(hw, "Reduced sqsets to %d\n", hw->num_sqsets);
+}
+
+static int
+csio_enable_msix(struct csio_hw *hw)
+{
+	int rv, i, j, k, n, min, cnt;
+	struct csio_msix_entries *entryp;
+	struct msix_entry *entries;
+	int extra = CSIO_EXTRA_VECS;
+	struct csio_scsi_cpu_info *info;
+
+	min = hw->num_pports + extra;
+	cnt = hw->num_sqsets + extra;
+
+	/* Max vectors required based on #niqs configured in fw */
+	if (hw->flags & CSIO_HWF_USING_SOFT_PARAMS || !csio_is_hw_master(hw))
+		cnt = min_t(uint8_t, hw->cfg_niq, cnt);
+
+	entries = kzalloc(sizeof(struct msix_entry) * cnt, GFP_KERNEL);
+	if (!entries)
+		return -ENOMEM;
+
+	for (i = 0; i < cnt; i++)
+		entries[i].entry = (uint16_t)i;
+
+	csio_dbg(hw, "FW supp #niq:%d, trying %d msix's\n", hw->cfg_niq, cnt);
+
+	while ((rv = pci_enable_msix(hw->pdev, entries, cnt)) >= min)
+		cnt = rv;
+	if (!rv) {
+		if (cnt < (hw->num_sqsets + extra)) {
+			csio_dbg(hw, "Reducing sqsets to %d\n", cnt - extra);
+			csio_reduce_sqsets(hw, cnt - extra);
+		}
+	} else {
+		if (rv > 0) {
+			pci_disable_msix(hw->pdev);
+			csio_info(hw, "Not using MSI-X, remainder:%d\n", rv);
+		}
+
+		kfree(entries);
+		return -ENOMEM;
+	}
+
+	/* Save off vectors */
+	for (i = 0; i < cnt; i++) {
+		entryp = &hw->msix_entries[i];
+		entryp->vector = entries[i].vector;
+	}
+
+	/* Distribute vectors */
+	k = 0;
+	csio_set_nondata_intr_idx(hw, entries[k].entry);
+	csio_set_mb_intr_idx(csio_hw_to_mbm(hw), entries[k++].entry);
+	csio_set_fwevt_intr_idx(hw, entries[k++].entry);
+
+	for (i = 0; i < hw->num_pports; i++) {
+		info = &hw->scsi_cpu_info[i];
+
+		for (j = 0; j < hw->num_scsi_msix_cpus; j++) {
+			n = (j % info->max_cpus) +  k;
+			hw->sqset[i][j].intr_idx = entries[n].entry;
+		}
+
+		k += info->max_cpus;
+	}
+
+	kfree(entries);
+	return 0;
+}
+
+void
+csio_intr_enable(struct csio_hw *hw)
+{
+	hw->intr_mode = CSIO_IM_NONE;
+	hw->flags &= ~CSIO_HWF_HOST_INTR_ENABLED;
+
+	/* Try MSIX, then MSI or fall back to INTx */
+	if ((csio_msi == 2) && !csio_enable_msix(hw))
+		hw->intr_mode = CSIO_IM_MSIX;
+	else {
+		/* Max iqs required based on #niqs configured in fw */
+		if (hw->flags & CSIO_HWF_USING_SOFT_PARAMS ||
+			!csio_is_hw_master(hw)) {
+			int extra = CSIO_EXTRA_MSI_IQS;
+
+			if (hw->cfg_niq < (hw->num_sqsets + extra)) {
+				csio_dbg(hw, "Reducing sqsets to %d\n",
+					 hw->cfg_niq - extra);
+				csio_reduce_sqsets(hw, hw->cfg_niq - extra);
+			}
+		}
+
+		if ((csio_msi == 1) && !pci_enable_msi(hw->pdev))
+			hw->intr_mode = CSIO_IM_MSI;
+		else
+			hw->intr_mode = CSIO_IM_INTX;
+	}
+
+	csio_dbg(hw, "Using %s interrupt mode.\n",
+		(hw->intr_mode == CSIO_IM_MSIX) ? "MSIX" :
+		((hw->intr_mode == CSIO_IM_MSI) ? "MSI" : "INTx"));
+}
+
+void
+csio_intr_disable(struct csio_hw *hw, bool free)
+{
+	csio_hw_intr_disable(hw);
+
+	switch (hw->intr_mode) {
+	case CSIO_IM_MSIX:
+		csio_disable_msix(hw, free);
+		break;
+	case CSIO_IM_MSI:
+		if (free)
+			free_irq(hw->pdev->irq, hw);
+		pci_disable_msi(hw->pdev);
+		break;
+	case CSIO_IM_INTX:
+		if (free)
+			free_irq(hw->pdev->irq, hw);
+		break;
+	default:
+		break;
+	}
+	hw->intr_mode = CSIO_IM_NONE;
+	hw->flags &= ~CSIO_HWF_HOST_INTR_ENABLED;
+}
diff --git a/drivers/scsi/csiostor/csio_scsi.c b/drivers/scsi/csiostor/csio_scsi.c
new file mode 100644
index 0000000..fdbd7da
--- /dev/null
+++ b/drivers/scsi/csiostor/csio_scsi.c
@@ -0,0 +1,2555 @@ 
+/*
+ * This file is part of the Chelsio FCoE driver for Linux.
+ *
+ * Copyright (c) 2008-2012 Chelsio Communications, Inc. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/ctype.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/compiler.h>
+#include <linux/export.h>
+#include <linux/module.h>
+#include <asm/unaligned.h>
+#include <asm/page.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_transport_fc.h>
+
+#include "csio_hw.h"
+#include "csio_lnode.h"
+#include "csio_rnode.h"
+#include "csio_scsi.h"
+#include "csio_init.h"
+
+int csio_scsi_eqsize = 65536;
+int csio_scsi_iqlen = 128;
+int csio_scsi_ioreqs = 2048;
+uint32_t csio_max_scan_tmo;
+uint32_t csio_delta_scan_tmo = 5;
+int csio_lun_qdepth = 32;
+
+static int csio_ddp_descs = 128;
+
+static int csio_do_abrt_cls(struct csio_hw *,
+				      struct csio_ioreq *, bool);
+
+static void csio_scsis_uninit(struct csio_ioreq *, enum csio_scsi_ev);
+static void csio_scsis_io_active(struct csio_ioreq *, enum csio_scsi_ev);
+static void csio_scsis_tm_active(struct csio_ioreq *, enum csio_scsi_ev);
+static void csio_scsis_aborting(struct csio_ioreq *, enum csio_scsi_ev);
+static void csio_scsis_closing(struct csio_ioreq *, enum csio_scsi_ev);
+static void csio_scsis_shost_cmpl_await(struct csio_ioreq *, enum csio_scsi_ev);
+
+/*
+ * csio_scsi_match_io - Match an ioreq with the given SCSI level data.
+ * @ioreq: The I/O request
+ * @sld: Level information
+ *
+ * Should be called with lock held.
+ *
+ */
+static bool
+csio_scsi_match_io(struct csio_ioreq *ioreq, struct csio_scsi_level_data *sld)
+{
+	struct scsi_cmnd *scmnd = csio_scsi_cmnd(ioreq);
+
+	switch (sld->level) {
+	case CSIO_LEV_LUN:
+		if (scmnd == NULL)
+			return false;
+
+		return ((ioreq->lnode == sld->lnode) &&
+			(ioreq->rnode == sld->rnode) &&
+			((uint64_t)scmnd->device->lun == sld->oslun));
+
+	case CSIO_LEV_RNODE:
+		return ((ioreq->lnode == sld->lnode) &&
+				(ioreq->rnode == sld->rnode));
+	case CSIO_LEV_LNODE:
+		return (ioreq->lnode == sld->lnode);
+	case CSIO_LEV_ALL:
+		return true;
+	default:
+		return false;
+	}
+}
+
+/*
+ * csio_scsi_gather_active_ios - Gather active I/Os based on level
+ * @scm: SCSI module
+ * @sld: Level information
+ * @dest: The queue where these I/Os have to be gathered.
+ *
+ * Should be called with lock held.
+ */
+static void
+csio_scsi_gather_active_ios(struct csio_scsim *scm,
+			    struct csio_scsi_level_data *sld,
+			    struct list_head *dest)
+{
+	struct list_head *tmp, *next;
+
+	if (list_empty(&scm->active_q))
+		return;
+
+	/* Just splice the entire active_q into dest */
+	if (sld->level == CSIO_LEV_ALL) {
+		list_splice_tail_init(&scm->active_q, dest);
+		return;
+	}
+
+	list_for_each_safe(tmp, next, &scm->active_q) {
+		if (csio_scsi_match_io((struct csio_ioreq *)tmp, sld)) {
+			list_del_init(tmp);
+			list_add_tail(tmp, dest);
+		}
+	}
+}
+
+static inline bool
+csio_scsi_itnexus_loss_error(uint16_t error)
+{
+	switch (error) {
+	case FW_ERR_LINK_DOWN:
+	case FW_RDEV_NOT_READY:
+	case FW_ERR_RDEV_LOST:
+	case FW_ERR_RDEV_LOGO:
+	case FW_ERR_RDEV_IMPL_LOGO:
+		return 1;
+	}
+	return 0;
+}
+
+static inline void
+csio_scsi_tag(struct scsi_cmnd *scmnd, uint8_t *tag, uint8_t hq,
+	      uint8_t oq, uint8_t sq)
+{
+	char stag[2];
+
+	if (scsi_populate_tag_msg(scmnd, stag)) {
+		switch (stag[0]) {
+		case HEAD_OF_QUEUE_TAG:
+			*tag = hq;
+			break;
+		case ORDERED_QUEUE_TAG:
+			*tag = oq;
+			break;
+		default:
+			*tag = sq;
+			break;
+		}
+	} else
+		*tag = 0;
+}
+
+/*
+ * csio_scsi_fcp_cmnd - Frame the SCSI FCP command paylod.
+ * @req: IO req structure.
+ * @addr: DMA location to place the payload.
+ *
+ * This routine is shared between FCP_WRITE, FCP_READ and FCP_CMD requests.
+ */
+static inline void
+csio_scsi_fcp_cmnd(struct csio_ioreq *req, void *addr)
+{
+	struct fcp_cmnd *fcp_cmnd = (struct fcp_cmnd *)addr;
+	struct scsi_cmnd *scmnd = csio_scsi_cmnd(req);
+
+	/* Check for Task Management */
+	if (likely(scmnd->SCp.Message == 0)) {
+		int_to_scsilun(scmnd->device->lun, &fcp_cmnd->fc_lun);
+		fcp_cmnd->fc_tm_flags = 0;
+		fcp_cmnd->fc_cmdref = 0;
+		fcp_cmnd->fc_pri_ta = 0;
+
+		memcpy(fcp_cmnd->fc_cdb, scmnd->cmnd, 16);
+		csio_scsi_tag(scmnd, &fcp_cmnd->fc_pri_ta,
+			      FCP_PTA_HEADQ, FCP_PTA_ORDERED, FCP_PTA_SIMPLE);
+		fcp_cmnd->fc_dl = cpu_to_be32(scsi_bufflen(scmnd));
+
+		if (req->nsge)
+			if (req->datadir == DMA_TO_DEVICE)
+				fcp_cmnd->fc_flags = FCP_CFL_WRDATA;
+			else
+				fcp_cmnd->fc_flags = FCP_CFL_RDDATA;
+		else
+			fcp_cmnd->fc_flags = 0;
+	} else {
+		memset(fcp_cmnd, 0, sizeof(*fcp_cmnd));
+		int_to_scsilun(scmnd->device->lun, &fcp_cmnd->fc_lun);
+		fcp_cmnd->fc_tm_flags = (uint8_t)scmnd->SCp.Message;
+	}
+}
+
+/*
+ * csio_scsi_init_cmd_wr - Initialize the SCSI CMD WR.
+ * @req: IO req structure.
+ * @addr: DMA location to place the payload.
+ * @size: Size of WR (including FW WR + immed data + rsp SG entry
+ *
+ * Wrapper for populating fw_scsi_cmd_wr.
+ */
+static inline void
+csio_scsi_init_cmd_wr(struct csio_ioreq *req, void *addr, uint32_t size)
+{
+	struct csio_hw *hw = req->lnode->hwp;
+	struct csio_rnode *rn = req->rnode;
+	struct fw_scsi_cmd_wr *wr = (struct fw_scsi_cmd_wr *)addr;
+	struct csio_dma_buf *dma_buf;
+	uint8_t imm = csio_hw_to_scsim(hw)->proto_cmd_len;
+
+	wr->op_immdlen = cpu_to_be32(FW_WR_OP(FW_SCSI_CMD_WR) |
+					  FW_SCSI_CMD_WR_IMMDLEN(imm));
+	wr->flowid_len16 = cpu_to_be32(FW_WR_FLOWID(rn->flowid) |
+					    FW_WR_LEN16(
+						DIV_ROUND_UP(size, 16)));
+
+	wr->cookie = (uintptr_t) req;
+	wr->iqid = (uint16_t)cpu_to_be16(csio_q_physiqid(hw, req->iq_idx));
+	wr->tmo_val = (uint8_t) req->tmo;
+	wr->r3 = 0;
+	memset(&wr->r5, 0, 8);
+
+	/* Get RSP DMA buffer */
+	dma_buf = &req->dma_buf;
+
+	/* Prepare RSP SGL */
+	wr->rsp_dmalen = cpu_to_be32(dma_buf->len);
+	wr->rsp_dmaaddr = cpu_to_be64(dma_buf->paddr);
+
+	wr->r6 = 0;
+
+	wr->u.fcoe.ctl_pri = 0;
+	wr->u.fcoe.cp_en_class = 0;
+	wr->u.fcoe.r4_lo[0] = 0;
+	wr->u.fcoe.r4_lo[1] = 0;
+
+	/* Frame a FCP command */
+	csio_scsi_fcp_cmnd(req, (void *)((uintptr_t)addr +
+				    sizeof(struct fw_scsi_cmd_wr)));
+}
+
+#define CSIO_SCSI_CMD_WR_SZ(_imm)					\
+	(sizeof(struct fw_scsi_cmd_wr) +		/* WR size */	\
+	 ALIGN((_imm), 16))				/* Immed data */
+
+#define CSIO_SCSI_CMD_WR_SZ_16(_imm)					\
+			(ALIGN(CSIO_SCSI_CMD_WR_SZ((_imm)), 16))
+
+/*
+ * csio_scsi_cmd - Create a SCSI CMD WR.
+ * @req: IO req structure.
+ *
+ * Gets a WR slot in the ingress queue and initializes it with SCSI CMD WR.
+ *
+ */
+static inline void
+csio_scsi_cmd(struct csio_ioreq *req)
+{
+	struct csio_wr_pair wrp;
+	struct csio_hw *hw = req->lnode->hwp;
+	struct csio_scsim *scsim = csio_hw_to_scsim(hw);
+	uint32_t size = CSIO_SCSI_CMD_WR_SZ_16(scsim->proto_cmd_len);
+
+	req->drv_status = csio_wr_get(hw, req->eq_idx, size, &wrp);
+	if (unlikely(req->drv_status != 0))
+		return;
+
+	if (wrp.size1 >= size) {
+		/* Initialize WR in one shot */
+		csio_scsi_init_cmd_wr(req, wrp.addr1, size);
+	} else {
+		uint8_t *tmpwr = csio_q_eq_wrap(hw, req->eq_idx);
+
+		/*
+		 * Make a temporary copy of the WR and write back
+		 * the copy into the WR pair.
+		 */
+		csio_scsi_init_cmd_wr(req, (void *)tmpwr, size);
+		memcpy(wrp.addr1, tmpwr, wrp.size1);
+		memcpy(wrp.addr2, tmpwr + wrp.size1, size - wrp.size1);
+	}
+}
+
+/*
+ * csio_scsi_init_ulptx_dsgl - Fill in a ULP_TX_SC_DSGL
+ * @hw: HW module
+ * @req: IO request
+ * @sgl: ULP TX SGL pointer.
+ *
+ */
+static inline void
+csio_scsi_init_ultptx_dsgl(struct csio_hw *hw, struct csio_ioreq *req,
+			   struct ulptx_sgl *sgl)
+{
+	struct ulptx_sge_pair *sge_pair = NULL;
+	struct scatterlist *sgel;
+	uint32_t i = 0;
+	uint32_t xfer_len;
+	struct list_head *tmp;
+	struct csio_dma_buf *dma_buf;
+	struct scsi_cmnd *scmnd = csio_scsi_cmnd(req);
+
+	sgl->cmd_nsge = htonl(ULPTX_CMD(ULP_TX_SC_DSGL) | ULPTX_MORE |
+				     ULPTX_NSGE(req->nsge));
+	/* Now add the data SGLs */
+	if (likely(!req->dcopy)) {
+		scsi_for_each_sg(scmnd, sgel, req->nsge, i) {
+			if (i == 0) {
+				sgl->addr0 = cpu_to_be64(sg_dma_address(sgel));
+				sgl->len0 = cpu_to_be32(sg_dma_len(sgel));
+				sge_pair = (struct ulptx_sge_pair *)(sgl + 1);
+				continue;
+			}
+			if ((i - 1) & 0x1) {
+				sge_pair->addr[1] = cpu_to_be64(
+							sg_dma_address(sgel));
+				sge_pair->len[1] = cpu_to_be32(
+							sg_dma_len(sgel));
+				sge_pair++;
+			} else {
+				sge_pair->addr[0] = cpu_to_be64(
+							sg_dma_address(sgel));
+				sge_pair->len[0] = cpu_to_be32(
+							sg_dma_len(sgel));
+			}
+		}
+	} else {
+		/* Program sg elements with driver's DDP buffer */
+		xfer_len = scsi_bufflen(scmnd);
+		list_for_each(tmp, &req->gen_list) {
+			dma_buf = (struct csio_dma_buf *)tmp;
+			if (i == 0) {
+				sgl->addr0 = cpu_to_be64(dma_buf->paddr);
+				sgl->len0 = cpu_to_be32(
+						min(xfer_len, dma_buf->len));
+				sge_pair = (struct ulptx_sge_pair *)(sgl + 1);
+			} else if ((i - 1) & 0x1) {
+				sge_pair->addr[1] = cpu_to_be64(dma_buf->paddr);
+				sge_pair->len[1] = cpu_to_be32(
+						min(xfer_len, dma_buf->len));
+				sge_pair++;
+			} else {
+				sge_pair->addr[0] = cpu_to_be64(dma_buf->paddr);
+				sge_pair->len[0] = cpu_to_be32(
+						min(xfer_len, dma_buf->len));
+			}
+			xfer_len -= min(xfer_len, dma_buf->len);
+			i++;
+		}
+	}
+}
+
+/*
+ * csio_scsi_init_read_wr - Initialize the READ SCSI WR.
+ * @req: IO req structure.
+ * @wrp: DMA location to place the payload.
+ * @size: Size of WR (including FW WR + immed data + rsp SG entry + data SGL
+ *
+ * Wrapper for populating fw_scsi_read_wr.
+ */
+static inline void
+csio_scsi_init_read_wr(struct csio_ioreq *req, void *wrp, uint32_t size)
+{
+	struct csio_hw *hw = req->lnode->hwp;
+	struct csio_rnode *rn = req->rnode;
+	struct fw_scsi_read_wr *wr = (struct fw_scsi_read_wr *)wrp;
+	struct ulptx_sgl *sgl;
+	struct csio_dma_buf *dma_buf;
+	uint8_t imm = csio_hw_to_scsim(hw)->proto_cmd_len;
+	struct scsi_cmnd *scmnd = csio_scsi_cmnd(req);
+
+	wr->op_immdlen = cpu_to_be32(FW_WR_OP(FW_SCSI_READ_WR) |
+				     FW_SCSI_READ_WR_IMMDLEN(imm));
+	wr->flowid_len16 = cpu_to_be32(FW_WR_FLOWID(rn->flowid) |
+				       FW_WR_LEN16(DIV_ROUND_UP(size, 16)));
+	wr->cookie = (uintptr_t)req;
+	wr->iqid = (uint16_t)cpu_to_be16(csio_q_physiqid(hw, req->iq_idx));
+	wr->tmo_val = (uint8_t)(req->tmo);
+	wr->use_xfer_cnt = 1;
+	wr->xfer_cnt = cpu_to_be32(scsi_bufflen(scmnd));
+	wr->ini_xfer_cnt = cpu_to_be32(scsi_bufflen(scmnd));
+	/* Get RSP DMA buffer */
+	dma_buf = &req->dma_buf;
+
+	/* Prepare RSP SGL */
+	wr->rsp_dmalen = cpu_to_be32(dma_buf->len);
+	wr->rsp_dmaaddr = cpu_to_be64(dma_buf->paddr);
+
+	wr->r4 = 0;
+
+	wr->u.fcoe.ctl_pri = 0;
+	wr->u.fcoe.cp_en_class = 0;
+	wr->u.fcoe.r3_lo[0] = 0;
+	wr->u.fcoe.r3_lo[1] = 0;
+	csio_scsi_fcp_cmnd(req, (void *)((uintptr_t)wrp +
+					sizeof(struct fw_scsi_read_wr)));
+
+	/* Move WR pointer past command and immediate data */
+	sgl = (struct ulptx_sgl *)((uintptr_t)wrp +
+			      sizeof(struct fw_scsi_read_wr) + ALIGN(imm, 16));
+
+	/* Fill in the DSGL */
+	csio_scsi_init_ultptx_dsgl(hw, req, sgl);
+}
+
+/*
+ * csio_scsi_init_write_wr - Initialize the WRITE SCSI WR.
+ * @req: IO req structure.
+ * @wrp: DMA location to place the payload.
+ * @size: Size of WR (including FW WR + immed data + rsp SG entry + data SGL
+ *
+ * Wrapper for populating fw_scsi_write_wr.
+ */
+static inline void
+csio_scsi_init_write_wr(struct csio_ioreq *req, void *wrp, uint32_t size)
+{
+	struct csio_hw *hw = req->lnode->hwp;
+	struct csio_rnode *rn = req->rnode;
+	struct fw_scsi_write_wr *wr = (struct fw_scsi_write_wr *)wrp;
+	struct ulptx_sgl *sgl;
+	struct csio_dma_buf *dma_buf;
+	uint8_t imm = csio_hw_to_scsim(hw)->proto_cmd_len;
+	struct scsi_cmnd *scmnd = csio_scsi_cmnd(req);
+
+	wr->op_immdlen = cpu_to_be32(FW_WR_OP(FW_SCSI_WRITE_WR) |
+				     FW_SCSI_WRITE_WR_IMMDLEN(imm));
+	wr->flowid_len16 = cpu_to_be32(FW_WR_FLOWID(rn->flowid) |
+				       FW_WR_LEN16(DIV_ROUND_UP(size, 16)));
+	wr->cookie = (uintptr_t)req;
+	wr->iqid = (uint16_t)cpu_to_be16(csio_q_physiqid(hw, req->iq_idx));
+	wr->tmo_val = (uint8_t)(req->tmo);
+	wr->use_xfer_cnt = 1;
+	wr->xfer_cnt = cpu_to_be32(scsi_bufflen(scmnd));
+	wr->ini_xfer_cnt = cpu_to_be32(scsi_bufflen(scmnd));
+	/* Get RSP DMA buffer */
+	dma_buf = &req->dma_buf;
+
+	/* Prepare RSP SGL */
+	wr->rsp_dmalen = cpu_to_be32(dma_buf->len);
+	wr->rsp_dmaaddr = cpu_to_be64(dma_buf->paddr);
+
+	wr->r4 = 0;
+
+	wr->u.fcoe.ctl_pri = 0;
+	wr->u.fcoe.cp_en_class = 0;
+	wr->u.fcoe.r3_lo[0] = 0;
+	wr->u.fcoe.r3_lo[1] = 0;
+	csio_scsi_fcp_cmnd(req, (void *)((uintptr_t)wrp +
+					sizeof(struct fw_scsi_write_wr)));
+
+	/* Move WR pointer past command and immediate data */
+	sgl = (struct ulptx_sgl *)((uintptr_t)wrp +
+			      sizeof(struct fw_scsi_write_wr) + ALIGN(imm, 16));
+
+	/* Fill in the DSGL */
+	csio_scsi_init_ultptx_dsgl(hw, req, sgl);
+}
+
+/* Calculate WR size needed for fw_scsi_read_wr/fw_scsi_write_wr */
+#define CSIO_SCSI_DATA_WRSZ(req, oper, sz, imm)				       \
+do {									       \
+	(sz) = sizeof(struct fw_scsi_##oper##_wr) +	/* WR size */          \
+	       ALIGN((imm), 16) +			/* Immed data */       \
+	       sizeof(struct ulptx_sgl);		/* ulptx_sgl */	       \
+									       \
+	if (unlikely((req)->nsge > 1))				               \
+		(sz) += (sizeof(struct ulptx_sge_pair) *		       \
+				(ALIGN(((req)->nsge - 1), 2) / 2));            \
+							/* Data SGE */	       \
+} while (0)
+
+/*
+ * csio_scsi_read - Create a SCSI READ WR.
+ * @req: IO req structure.
+ *
+ * Gets a WR slot in the ingress queue and initializes it with
+ * SCSI READ WR.
+ *
+ */
+static inline void
+csio_scsi_read(struct csio_ioreq *req)
+{
+	struct csio_wr_pair wrp;
+	uint32_t size;
+	struct csio_hw *hw = req->lnode->hwp;
+	struct csio_scsim *scsim = csio_hw_to_scsim(hw);
+
+	CSIO_SCSI_DATA_WRSZ(req, read, size, scsim->proto_cmd_len);
+	size = ALIGN(size, 16);
+
+	req->drv_status = csio_wr_get(hw, req->eq_idx, size, &wrp);
+	if (likely(req->drv_status == 0)) {
+		if (likely(wrp.size1 >= size)) {
+			/* Initialize WR in one shot */
+			csio_scsi_init_read_wr(req, wrp.addr1, size);
+		} else {
+			uint8_t *tmpwr = csio_q_eq_wrap(hw, req->eq_idx);
+			/*
+			 * Make a temporary copy of the WR and write back
+			 * the copy into the WR pair.
+			 */
+			csio_scsi_init_read_wr(req, (void *)tmpwr, size);
+			memcpy(wrp.addr1, tmpwr, wrp.size1);
+			memcpy(wrp.addr2, tmpwr + wrp.size1, size - wrp.size1);
+		}
+	}
+}
+
+/*
+ * csio_scsi_write - Create a SCSI WRITE WR.
+ * @req: IO req structure.
+ *
+ * Gets a WR slot in the ingress queue and initializes it with
+ * SCSI WRITE WR.
+ *
+ */
+static inline void
+csio_scsi_write(struct csio_ioreq *req)
+{
+	struct csio_wr_pair wrp;
+	uint32_t size;
+	struct csio_hw *hw = req->lnode->hwp;
+	struct csio_scsim *scsim = csio_hw_to_scsim(hw);
+
+	CSIO_SCSI_DATA_WRSZ(req, write, size, scsim->proto_cmd_len);
+	size = ALIGN(size, 16);
+
+	req->drv_status = csio_wr_get(hw, req->eq_idx, size, &wrp);
+	if (likely(req->drv_status == 0)) {
+		if (likely(wrp.size1 >= size)) {
+			/* Initialize WR in one shot */
+			csio_scsi_init_write_wr(req, wrp.addr1, size);
+		} else {
+			uint8_t *tmpwr = csio_q_eq_wrap(hw, req->eq_idx);
+			/*
+			 * Make a temporary copy of the WR and write back
+			 * the copy into the WR pair.
+			 */
+			csio_scsi_init_write_wr(req, (void *)tmpwr, size);
+			memcpy(wrp.addr1, tmpwr, wrp.size1);
+			memcpy(wrp.addr2, tmpwr + wrp.size1, size - wrp.size1);
+		}
+	}
+}
+
+/*
+ * csio_setup_ddp - Setup DDP buffers for Read request.
+ * @req: IO req structure.
+ *
+ * Checks SGLs/Data buffers are virtually contiguous required for DDP.
+ * If contiguous,driver posts SGLs in the WR otherwise post internal
+ * buffers for such request for DDP.
+ */
+static inline void
+csio_setup_ddp(struct csio_scsim *scsim, struct csio_ioreq *req)
+{
+#ifdef __CSIO_DEBUG__
+	struct csio_hw *hw = req->lnode->hwp;
+#endif
+	struct scatterlist *sgel = NULL;
+	struct scsi_cmnd *scmnd = csio_scsi_cmnd(req);
+	uint64_t sg_addr = 0;
+	uint32_t ddp_pagesz = 4096;
+	uint32_t buf_off;
+	struct csio_dma_buf *dma_buf = NULL;
+	uint32_t alloc_len = 0;
+	uint32_t xfer_len = 0;
+	uint32_t sg_len = 0;
+	uint32_t i;
+
+	scsi_for_each_sg(scmnd, sgel, req->nsge, i) {
+		sg_addr = sg_dma_address(sgel);
+		sg_len	= sg_dma_len(sgel);
+
+		buf_off = sg_addr & (ddp_pagesz - 1);
+
+		/* Except 1st buffer,all buffer addr have to be Page aligned */
+		if (i != 0 && buf_off) {
+			csio_dbg(hw, "SGL addr not DDP aligned (%llx:%d)\n",
+				 sg_addr, sg_len);
+			goto unaligned;
+		}
+
+		/* Except last buffer,all buffer must end on page boundary */
+		if ((i != (req->nsge - 1)) &&
+			((buf_off + sg_len) & (ddp_pagesz - 1))) {
+			csio_dbg(hw,
+				 "SGL addr not ending on page boundary"
+				 "(%llx:%d)\n", sg_addr, sg_len);
+			goto unaligned;
+		}
+	}
+
+	/* SGL's are virtually contiguous. HW will DDP to SGLs */
+	req->dcopy = 0;
+	csio_scsi_read(req);
+
+	return;
+
+unaligned:
+	CSIO_INC_STATS(scsim, n_unaligned);
+	/*
+	 * For unaligned SGLs, driver will allocate internal DDP buffer.
+	 * Once command is completed data from DDP buffer copied to SGLs
+	 */
+	req->dcopy = 1;
+
+	/* Use gen_list to store the DDP buffers */
+	INIT_LIST_HEAD(&req->gen_list);
+	xfer_len = scsi_bufflen(scmnd);
+
+	i = 0;
+	/* Allocate ddp buffers for this request */
+	while (alloc_len < xfer_len) {
+		dma_buf = csio_get_scsi_ddp(scsim);
+		if (dma_buf == NULL || i > scsim->max_sge) {
+			req->drv_status = -EBUSY;
+			break;
+		}
+		alloc_len += dma_buf->len;
+		/* Added to IO req */
+		list_add_tail(&dma_buf->list, &req->gen_list);
+		i++;
+	}
+
+	if (!req->drv_status) {
+		/* set number of ddp bufs used */
+		req->nsge = i;
+		csio_scsi_read(req);
+		return;
+	}
+
+	 /* release dma descs */
+	if (i > 0)
+		csio_put_scsi_ddp_list(scsim, &req->gen_list, i);
+}
+
+/*
+ * csio_scsi_init_abrt_cls_wr - Initialize an ABORT/CLOSE WR.
+ * @req: IO req structure.
+ * @addr: DMA location to place the payload.
+ * @size: Size of WR
+ * @abort: abort OR close
+ *
+ * Wrapper for populating fw_scsi_cmd_wr.
+ */
+static inline void
+csio_scsi_init_abrt_cls_wr(struct csio_ioreq *req, void *addr, uint32_t size,
+			   bool abort)
+{
+	struct csio_hw *hw = req->lnode->hwp;
+	struct csio_rnode *rn = req->rnode;
+	struct fw_scsi_abrt_cls_wr *wr = (struct fw_scsi_abrt_cls_wr *)addr;
+
+	wr->op_immdlen = cpu_to_be32(FW_WR_OP(FW_SCSI_ABRT_CLS_WR));
+	wr->flowid_len16 = cpu_to_be32(FW_WR_FLOWID(rn->flowid) |
+					    FW_WR_LEN16(
+						DIV_ROUND_UP(size, 16)));
+
+	wr->cookie = (uintptr_t) req;
+	wr->iqid = (uint16_t)cpu_to_be16(csio_q_physiqid(hw, req->iq_idx));
+	wr->tmo_val = (uint8_t) req->tmo;
+	/* 0 for CHK_ALL_IO tells FW to look up t_cookie */
+	wr->sub_opcode_to_chk_all_io =
+				(FW_SCSI_ABRT_CLS_WR_SUB_OPCODE(abort) |
+				 FW_SCSI_ABRT_CLS_WR_CHK_ALL_IO(0));
+	wr->r3[0] = 0;
+	wr->r3[1] = 0;
+	wr->r3[2] = 0;
+	wr->r3[3] = 0;
+	/* Since we re-use the same ioreq for abort as well */
+	wr->t_cookie = (uintptr_t) req;
+}
+
+static inline void
+csio_scsi_abrt_cls(struct csio_ioreq *req, bool abort)
+{
+	struct csio_wr_pair wrp;
+	struct csio_hw *hw = req->lnode->hwp;
+	uint32_t size = ALIGN(sizeof(struct fw_scsi_abrt_cls_wr), 16);
+
+	req->drv_status = csio_wr_get(hw, req->eq_idx, size, &wrp);
+	if (req->drv_status != 0)
+		return;
+
+	if (wrp.size1 >= size) {
+		/* Initialize WR in one shot */
+		csio_scsi_init_abrt_cls_wr(req, wrp.addr1, size, abort);
+	} else {
+		uint8_t *tmpwr = csio_q_eq_wrap(hw, req->eq_idx);
+		/*
+		 * Make a temporary copy of the WR and write back
+		 * the copy into the WR pair.
+		 */
+		csio_scsi_init_abrt_cls_wr(req, (void *)tmpwr, size, abort);
+		memcpy(wrp.addr1, tmpwr, wrp.size1);
+		memcpy(wrp.addr2, tmpwr + wrp.size1, size - wrp.size1);
+	}
+}
+
+/*****************************************************************************/
+/* START: SCSI SM                                                            */
+/*****************************************************************************/
+static void
+csio_scsis_uninit(struct csio_ioreq *req, enum csio_scsi_ev evt)
+{
+	struct csio_hw *hw = req->lnode->hwp;
+	struct csio_scsim *scsim = csio_hw_to_scsim(hw);
+
+	switch (evt) {
+	case CSIO_SCSIE_START_IO:
+
+		if (req->nsge) {
+			if (req->datadir == DMA_TO_DEVICE) {
+				req->dcopy = 0;
+				csio_scsi_write(req);
+			} else
+				csio_setup_ddp(scsim, req);
+		} else {
+			csio_scsi_cmd(req);
+		}
+
+		if (likely(req->drv_status == 0)) {
+			/* change state and enqueue on active_q */
+			csio_set_state(&req->sm, csio_scsis_io_active);
+			list_add_tail(&req->sm.sm_list, &scsim->active_q);
+			csio_wr_issue(hw, req->eq_idx, false);
+			CSIO_INC_STATS(scsim, n_active);
+
+			return;
+		}
+		break;
+
+	case CSIO_SCSIE_START_TM:
+		csio_scsi_cmd(req);
+		if (req->drv_status == 0) {
+			/*
+			 * NOTE: We collect the affected I/Os prior to issuing
+			 * LUN reset, and not after it. This is to prevent
+			 * aborting I/Os that get issued after the LUN reset,
+			 * but prior to LUN reset completion (in the event that
+			 * the host stack has not blocked I/Os to a LUN that is
+			 * being reset.
+			 */
+			csio_set_state(&req->sm, csio_scsis_tm_active);
+			list_add_tail(&req->sm.sm_list, &scsim->active_q);
+			csio_wr_issue(hw, req->eq_idx, false);
+			CSIO_INC_STATS(scsim, n_tm_active);
+		}
+		return;
+
+	case CSIO_SCSIE_ABORT:
+	case CSIO_SCSIE_CLOSE:
+		/*
+		 * NOTE:
+		 * We could get here due to  :
+		 * - a window in the cleanup path of the SCSI module
+		 *   (csio_scsi_abort_io()). Please see NOTE in this function.
+		 * - a window in the time we tried to issue an abort/close
+		 *   of a request to FW, and the FW completed the request
+		 *   itself.
+		 *   Print a message for now, and return INVAL either way.
+		 */
+		req->drv_status = -EINVAL;
+		csio_warn(hw, "Trying to abort/close completed IO:%p!\n", req);
+		break;
+
+	default:
+		csio_dbg(hw, "Unhandled event:%d sent to req:%p\n", evt, req);
+		CSIO_DB_ASSERT(0);
+	}
+}
+
+static void
+csio_scsis_io_active(struct csio_ioreq *req, enum csio_scsi_ev evt)
+{
+	struct csio_hw *hw = req->lnode->hwp;
+	struct csio_scsim *scm = csio_hw_to_scsim(hw);
+	struct csio_rnode *rn;
+
+	switch (evt) {
+	case CSIO_SCSIE_COMPLETED:
+		CSIO_DEC_STATS(scm, n_active);
+		list_del_init(&req->sm.sm_list);
+		csio_set_state(&req->sm, csio_scsis_uninit);
+		/*
+		 * In MSIX mode, with multiple queues, the SCSI compeltions
+		 * could reach us sooner than the FW events sent to indicate
+		 * I-T nexus loss (link down, remote device logo etc). We
+		 * dont want to be returning such I/Os to the upper layer
+		 * immediately, since we wouldnt have reported the I-T nexus
+		 * loss itself. This forces us to serialize such completions
+		 * with the reporting of the I-T nexus loss. Therefore, we
+		 * internally queue up such up such completions in the rnode.
+		 * The reporting of I-T nexus loss to the upper layer is then
+		 * followed by the returning of I/Os in this internal queue.
+		 * Having another state alongwith another queue helps us take
+		 * actions for events such as ABORT received while we are
+		 * in this rnode queue.
+		 */
+		if (unlikely(req->wr_status != FW_SUCCESS)) {
+			rn = req->rnode;
+			/*
+			 * FW says remote device is lost, but rnode
+			 * doesnt reflect it.
+			 */
+			if (csio_scsi_itnexus_loss_error(req->wr_status) &&
+						csio_is_rnode_ready(rn)) {
+				csio_set_state(&req->sm,
+						csio_scsis_shost_cmpl_await);
+				list_add_tail(&req->sm.sm_list,
+					      &rn->host_cmpl_q);
+			}
+		}
+
+		break;
+
+	case CSIO_SCSIE_ABORT:
+		csio_scsi_abrt_cls(req, SCSI_ABORT);
+		if (req->drv_status == 0) {
+			csio_wr_issue(hw, req->eq_idx, false);
+			csio_set_state(&req->sm, csio_scsis_aborting);
+		}
+		break;
+
+	case CSIO_SCSIE_CLOSE:
+		csio_scsi_abrt_cls(req, SCSI_CLOSE);
+		if (req->drv_status == 0) {
+			csio_wr_issue(hw, req->eq_idx, false);
+			csio_set_state(&req->sm, csio_scsis_closing);
+		}
+		break;
+
+	case CSIO_SCSIE_DRVCLEANUP:
+		req->wr_status = FW_HOSTERROR;
+		CSIO_DEC_STATS(scm, n_active);
+		csio_set_state(&req->sm, csio_scsis_uninit);
+		break;
+
+	default:
+		csio_dbg(hw, "Unhandled event:%d sent to req:%p\n", evt, req);
+		CSIO_DB_ASSERT(0);
+	}
+}
+
+static void
+csio_scsis_tm_active(struct csio_ioreq *req, enum csio_scsi_ev evt)
+{
+	struct csio_hw *hw = req->lnode->hwp;
+	struct csio_scsim *scm = csio_hw_to_scsim(hw);
+
+	switch (evt) {
+	case CSIO_SCSIE_COMPLETED:
+		CSIO_DEC_STATS(scm, n_tm_active);
+		list_del_init(&req->sm.sm_list);
+		csio_set_state(&req->sm, csio_scsis_uninit);
+
+		break;
+
+	case CSIO_SCSIE_ABORT:
+		csio_scsi_abrt_cls(req, SCSI_ABORT);
+		if (req->drv_status == 0) {
+			csio_wr_issue(hw, req->eq_idx, false);
+			csio_set_state(&req->sm, csio_scsis_aborting);
+		}
+		break;
+
+
+	case CSIO_SCSIE_CLOSE:
+		csio_scsi_abrt_cls(req, SCSI_CLOSE);
+		if (req->drv_status == 0) {
+			csio_wr_issue(hw, req->eq_idx, false);
+			csio_set_state(&req->sm, csio_scsis_closing);
+		}
+		break;
+
+	case CSIO_SCSIE_DRVCLEANUP:
+		req->wr_status = FW_HOSTERROR;
+		CSIO_DEC_STATS(scm, n_tm_active);
+		csio_set_state(&req->sm, csio_scsis_uninit);
+		break;
+
+	default:
+		csio_dbg(hw, "Unhandled event:%d sent to req:%p\n", evt, req);
+		CSIO_DB_ASSERT(0);
+	}
+}
+
+static void
+csio_scsis_aborting(struct csio_ioreq *req, enum csio_scsi_ev evt)
+{
+	struct csio_hw *hw = req->lnode->hwp;
+	struct csio_scsim *scm = csio_hw_to_scsim(hw);
+
+	switch (evt) {
+	case CSIO_SCSIE_COMPLETED:
+		csio_dbg(hw,
+			 "ioreq %p recvd cmpltd (wr_status:%d) "
+			 "in aborting st\n", req, req->wr_status);
+		/*
+		 * Use -ECANCELED to explicitly tell the ABORTED event that
+		 * the original I/O was returned to driver by FW.
+		 * We dont really care if the I/O was returned with success by
+		 * FW (because the ABORT and completion of the I/O crossed each
+		 * other), or any other return value. Once we are in aborting
+		 * state, the success or failure of the I/O is unimportant to
+		 * us.
+		 */
+		req->drv_status = -ECANCELED;
+		break;
+
+	case CSIO_SCSIE_ABORT:
+		CSIO_INC_STATS(scm, n_abrt_dups);
+		break;
+
+	case CSIO_SCSIE_ABORTED:
+
+		csio_dbg(hw, "abort of %p return status:0x%x drv_status:%x\n",
+			 req, req->wr_status, req->drv_status);
+		/*
+		 * Check if original I/O WR completed before the Abort
+		 * completion.
+		 */
+		if (req->drv_status != -ECANCELED) {
+			csio_warn(hw,
+				  "Abort completed before original I/O,"
+				   " req:%p\n", req);
+			CSIO_DB_ASSERT(0);
+		}
+
+		/*
+		 * There are the following possible scenarios:
+		 * 1. The abort completed successfully, FW returned FW_SUCCESS.
+		 * 2. The completion of an I/O and the receipt of
+		 *    abort for that I/O by the FW crossed each other.
+		 *    The FW returned FW_EINVAL. The original I/O would have
+		 *    returned with FW_SUCCESS or any other SCSI error.
+		 * 3. The FW couldnt sent the abort out on the wire, as there
+		 *    was an I-T nexus loss (link down, remote device logged
+		 *    out etc). FW sent back an appropriate IT nexus loss status
+		 *    for the abort.
+		 * 4. FW sent an abort, but abort timed out (remote device
+		 *    didnt respond). FW replied back with
+		 *    FW_SCSI_ABORT_TIMEDOUT.
+		 * 5. FW couldnt genuinely abort the request for some reason,
+		 *    and sent us an error.
+		 *
+		 * The first 3 scenarios are treated as  succesful abort
+		 * operations by the host, while the last 2 are failed attempts
+		 * to abort. Manipulate the return value of the request
+		 * appropriately, so that host can convey these results
+		 * back to the upper layer.
+		 */
+		if ((req->wr_status == FW_SUCCESS) ||
+		    (req->wr_status == FW_EINVAL) ||
+		    csio_scsi_itnexus_loss_error(req->wr_status))
+			req->wr_status = FW_SCSI_ABORT_REQUESTED;
+
+		CSIO_DEC_STATS(scm, n_active);
+		list_del_init(&req->sm.sm_list);
+		csio_set_state(&req->sm, csio_scsis_uninit);
+		break;
+
+	case CSIO_SCSIE_DRVCLEANUP:
+		req->wr_status = FW_HOSTERROR;
+		CSIO_DEC_STATS(scm, n_active);
+		csio_set_state(&req->sm, csio_scsis_uninit);
+		break;
+
+	case CSIO_SCSIE_CLOSE:
+		/*
+		 * We can receive this event from the module
+		 * cleanup paths, if the FW forgot to reply to the ABORT WR
+		 * and left this ioreq in this state. For now, just ignore
+		 * the event. The CLOSE event is sent to this state, as
+		 * the LINK may have already gone down.
+		 */
+		break;
+
+	default:
+		csio_dbg(hw, "Unhandled event:%d sent to req:%p\n", evt, req);
+		CSIO_DB_ASSERT(0);
+	}
+}
+
+static void
+csio_scsis_closing(struct csio_ioreq *req, enum csio_scsi_ev evt)
+{
+	struct csio_hw *hw = req->lnode->hwp;
+	struct csio_scsim *scm = csio_hw_to_scsim(hw);
+
+	switch (evt) {
+	case CSIO_SCSIE_COMPLETED:
+		csio_dbg(hw,
+			 "ioreq %p recvd cmpltd (wr_status:%d) "
+			 "in closing st\n", req, req->wr_status);
+		/*
+		 * Use -ECANCELED to explicitly tell the CLOSED event that
+		 * the original I/O was returned to driver by FW.
+		 * We dont really care if the I/O was returned with success by
+		 * FW (because the CLOSE and completion of the I/O crossed each
+		 * other), or any other return value. Once we are in aborting
+		 * state, the success or failure of the I/O is unimportant to
+		 * us.
+		 */
+		req->drv_status = -ECANCELED;
+		break;
+
+	case CSIO_SCSIE_CLOSED:
+		/*
+		 * Check if original I/O WR completed before the Close
+		 * completion.
+		 */
+		if (req->drv_status != -ECANCELED) {
+			csio_fatal(hw,
+				   "Close completed before original I/O,"
+				   " req:%p\n", req);
+			CSIO_DB_ASSERT(0);
+		}
+
+		/*
+		 * Either close succeeded, or we issued close to FW at the
+		 * same time FW compelted it to us. Either way, the I/O
+		 * is closed.
+		 */
+		CSIO_DB_ASSERT((req->wr_status == FW_SUCCESS) ||
+					(req->wr_status == FW_EINVAL));
+		req->wr_status = FW_SCSI_CLOSE_REQUESTED;
+
+		CSIO_DEC_STATS(scm, n_active);
+		list_del_init(&req->sm.sm_list);
+		csio_set_state(&req->sm, csio_scsis_uninit);
+		break;
+
+	case CSIO_SCSIE_CLOSE:
+		break;
+
+	case CSIO_SCSIE_DRVCLEANUP:
+		req->wr_status = FW_HOSTERROR;
+		CSIO_DEC_STATS(scm, n_active);
+		csio_set_state(&req->sm, csio_scsis_uninit);
+		break;
+
+	default:
+		csio_dbg(hw, "Unhandled event:%d sent to req:%p\n", evt, req);
+		CSIO_DB_ASSERT(0);
+	}
+}
+
+static void
+csio_scsis_shost_cmpl_await(struct csio_ioreq *req, enum csio_scsi_ev evt)
+{
+	switch (evt) {
+	case CSIO_SCSIE_ABORT:
+	case CSIO_SCSIE_CLOSE:
+		/*
+		 * Just succeed the abort request, and hope that
+		 * the remote device unregister path will cleanup
+		 * this I/O to the upper layer within a sane
+		 * amount of time.
+		 */
+		/*
+		 * A close can come in during a LINK DOWN. The FW would have
+		 * returned us the I/O back, but not the remote device lost
+		 * FW event. In this interval, if the I/O times out at the upper
+		 * layer, a close can come in. Take the same action as abort:
+		 * return success, and hope that the remote device unregister
+		 * path will cleanup this I/O. If the FW still doesnt send
+		 * the msg, the close times out, and the upper layer resorts
+		 * to the next level of error recovery.
+		 */
+		req->drv_status = 0;
+		break;
+	case CSIO_SCSIE_DRVCLEANUP:
+		csio_set_state(&req->sm, csio_scsis_uninit);
+		break;
+	default:
+		csio_dbg(req->lnode->hwp, "Unhandled event:%d sent to req:%p\n",
+			 evt, req);
+		CSIO_DB_ASSERT(0);
+	}
+}
+
+/*
+ * csio_scsi_cmpl_handler - WR completion handler for SCSI.
+ * @hw: HW module.
+ * @wr: The completed WR from the ingress queue.
+ * @len: Length of the WR.
+ * @flb: Freelist buffer array.
+ * @priv: Private object
+ * @scsiwr: Pointer to SCSI WR.
+ *
+ * This is the WR completion handler called per completion from the
+ * ISR. It is called with lock held. It walks past the RSS and CPL message
+ * header where the actual WR is present.
+ * It then gets the status, WR handle (ioreq pointer) and the len of
+ * the WR, based on WR opcode. Only on a non-good status is the entire
+ * WR copied into the WR cache (ioreq->fw_wr).
+ * The ioreq corresponding to the WR is returned to the caller.
+ * NOTE: The SCSI queue doesnt allocate a freelist today, hence
+ * no freelist buffer is expected.
+ */
+struct csio_ioreq *
+csio_scsi_cmpl_handler(struct csio_hw *hw, void *wr, uint32_t len,
+		     struct csio_fl_dma_buf *flb, void *priv, uint8_t **scsiwr)
+{
+	struct csio_ioreq *ioreq = NULL;
+	struct cpl_fw6_msg *cpl;
+	uint8_t *tempwr;
+	uint8_t	status;
+	struct csio_scsim *scm = csio_hw_to_scsim(hw);
+
+	/* skip RSS header */
+	cpl = (struct cpl_fw6_msg *)((uintptr_t)wr + sizeof(__be64));
+
+	if (unlikely(cpl->opcode != CPL_FW6_MSG)) {
+		csio_warn(hw, "Error: Invalid CPL msg %x recvd on SCSI q\n",
+			  cpl->opcode);
+		CSIO_INC_STATS(scm, n_inval_cplop);
+		return NULL;
+	}
+
+	tempwr = (uint8_t *)(cpl->data);
+	status = csio_wr_status(tempwr);
+	*scsiwr = tempwr;
+
+	if (likely((*tempwr == FW_SCSI_READ_WR) ||
+			(*tempwr == FW_SCSI_WRITE_WR) ||
+			(*tempwr == FW_SCSI_CMD_WR))) {
+		ioreq = (struct csio_ioreq *)((uintptr_t)
+				 (((struct fw_scsi_read_wr *)tempwr)->cookie));
+		CSIO_DB_ASSERT(virt_addr_valid(ioreq));
+
+		ioreq->wr_status = status;
+
+		return ioreq;
+	}
+
+	if (*tempwr == FW_SCSI_ABRT_CLS_WR) {
+		ioreq = (struct csio_ioreq *)((uintptr_t)
+			 (((struct fw_scsi_abrt_cls_wr *)tempwr)->cookie));
+		CSIO_DB_ASSERT(virt_addr_valid(ioreq));
+
+		ioreq->wr_status = status;
+		return ioreq;
+	}
+
+	csio_warn(hw, "WR with invalid opcode in SCSI IQ: %x\n", *tempwr);
+	CSIO_INC_STATS(scm, n_inval_scsiop);
+	return NULL;
+}
+
+/*
+ * csio_scsi_cleanup_io_q - Cleanup the given queue.
+ * @scm: SCSI module.
+ * @q: Queue to be cleaned up.
+ *
+ * Called with lock held. Has to exit with lock held.
+ */
+void
+csio_scsi_cleanup_io_q(struct csio_scsim *scm, struct list_head *q)
+{
+	struct csio_hw *hw = scm->hw;
+	struct csio_ioreq *ioreq;
+	struct list_head *tmp, *next;
+	struct scsi_cmnd *scmnd;
+
+	/* Call back the completion routines of the active_q */
+	list_for_each_safe(tmp, next, q) {
+		ioreq = (struct csio_ioreq *)tmp;
+		csio_scsi_drvcleanup(ioreq);
+		list_del_init(&ioreq->sm.sm_list);
+		scmnd = csio_scsi_cmnd(ioreq);
+		spin_unlock_irq(&hw->lock);
+
+		/*
+		 * Upper layers may have cleared this command, hence this
+		 * check to avoid accessing stale references.
+		 */
+		if (scmnd != NULL)
+			ioreq->io_cbfn(hw, ioreq);
+
+		spin_lock_irq(&scm->freelist_lock);
+		csio_put_scsi_ioreq(scm, ioreq);
+		spin_unlock_irq(&scm->freelist_lock);
+
+		spin_lock_irq(&hw->lock);
+	}
+}
+
+#define CSIO_SCSI_ABORT_Q_POLL_MS		2000
+
+static void
+csio_abrt_cls(struct csio_ioreq *ioreq, struct scsi_cmnd *scmnd)
+{
+	struct csio_lnode *ln = ioreq->lnode;
+	struct csio_hw *hw = ln->hwp;
+	int ready = 0;
+	struct csio_scsim *scsim = csio_hw_to_scsim(hw);
+	int rv;
+
+	if (csio_scsi_cmnd(ioreq) != scmnd) {
+		CSIO_INC_STATS(scsim, n_abrt_race_comp);
+		return;
+	}
+
+	ready = csio_is_lnode_ready(ln);
+
+	rv = csio_do_abrt_cls(hw, ioreq, (ready ? SCSI_ABORT : SCSI_CLOSE));
+	if (rv != 0) {
+		if (ready)
+			CSIO_INC_STATS(scsim, n_abrt_busy_error);
+		else
+			CSIO_INC_STATS(scsim, n_cls_busy_error);
+	}
+}
+
+/*
+ * csio_scsi_abort_io_q - Abort all I/Os on given queue
+ * @scm: SCSI module.
+ * @q: Queue to abort.
+ * @tmo: Timeout in ms
+ *
+ * Attempt to abort all I/Os on given queue, and wait for a max
+ * of tmo milliseconds for them to complete. Returns success
+ * if all I/Os are aborted. Else returns -ETIMEDOUT.
+ * Should be entered with lock held. Exits with lock held.
+ * NOTE:
+ * Lock has to be held across the loop that aborts I/Os, since dropping the lock
+ * in between can cause the list to be corrupted. As a result, the caller
+ * of this function has to ensure that the number of I/os to be aborted
+ * is finite enough to not cause lock-held-for-too-long issues.
+ */
+static int
+csio_scsi_abort_io_q(struct csio_scsim *scm, struct list_head *q, uint32_t tmo)
+{
+	struct csio_hw *hw = scm->hw;
+	struct list_head *tmp, *next;
+	int count = DIV_ROUND_UP(tmo, CSIO_SCSI_ABORT_Q_POLL_MS);
+	struct scsi_cmnd *scmnd;
+
+	if (list_empty(q))
+		return 0;
+
+	csio_dbg(hw, "Aborting SCSI I/Os\n");
+
+	/* Now abort/close I/Os in the queue passed */
+	list_for_each_safe(tmp, next, q) {
+		scmnd = csio_scsi_cmnd((struct csio_ioreq *)tmp);
+		csio_abrt_cls((struct csio_ioreq *)tmp, scmnd);
+	}
+
+	/* Wait till all active I/Os are completed/aborted/closed */
+	while (!list_empty(q) && count--) {
+		spin_unlock_irq(&hw->lock);
+		msleep(CSIO_SCSI_ABORT_Q_POLL_MS);
+		spin_lock_irq(&hw->lock);
+	}
+
+	/* all aborts completed */
+	if (list_empty(q))
+		return 0;
+
+	return -ETIMEDOUT;
+}
+
+/*
+ * csio_scsim_cleanup_io - Cleanup all I/Os in SCSI module.
+ * @scm: SCSI module.
+ * @abort: abort required.
+ * Called with lock held, should exit with lock held.
+ * Can sleep when waiting for I/Os to complete.
+ */
+int
+csio_scsim_cleanup_io(struct csio_scsim *scm, bool abort)
+{
+	struct csio_hw *hw = scm->hw;
+	int rv = 0;
+	int count = DIV_ROUND_UP(60 * 1000, CSIO_SCSI_ABORT_Q_POLL_MS);
+
+	/* No I/Os pending */
+	if (list_empty(&scm->active_q))
+		return 0;
+
+	/* Wait until all active I/Os are completed */
+	while (!list_empty(&scm->active_q) && count--) {
+		spin_unlock_irq(&hw->lock);
+		msleep(CSIO_SCSI_ABORT_Q_POLL_MS);
+		spin_lock_irq(&hw->lock);
+	}
+
+	/* all I/Os completed */
+	if (list_empty(&scm->active_q))
+		return 0;
+
+	/* Else abort */
+	if (abort) {
+		rv = csio_scsi_abort_io_q(scm, &scm->active_q, 30000);
+		if (rv == 0)
+			return rv;
+		csio_dbg(hw, "Some I/O aborts timed out, cleaning up..\n");
+	}
+
+	csio_scsi_cleanup_io_q(scm, &scm->active_q);
+
+	CSIO_DB_ASSERT(list_empty(&scm->active_q));
+
+	return rv;
+}
+
+/*
+ * csio_scsim_cleanup_io_lnode - Cleanup all I/Os of given lnode.
+ * @scm: SCSI module.
+ * @lnode: lnode
+ *
+ * Called with lock held, should exit with lock held.
+ * Can sleep (with dropped lock) when waiting for I/Os to complete.
+ */
+int
+csio_scsim_cleanup_io_lnode(struct csio_scsim *scm, struct csio_lnode *ln)
+{
+	struct csio_hw *hw = scm->hw;
+	struct csio_scsi_level_data sld;
+	int rv;
+	int count = DIV_ROUND_UP(60 * 1000, CSIO_SCSI_ABORT_Q_POLL_MS);
+
+	csio_dbg(hw, "Gathering all SCSI I/Os on lnode %p\n", ln);
+
+	sld.level = CSIO_LEV_LNODE;
+	sld.lnode = ln;
+	INIT_LIST_HEAD(&ln->cmpl_q);
+	csio_scsi_gather_active_ios(scm, &sld, &ln->cmpl_q);
+
+	/* No I/Os pending on this lnode  */
+	if (list_empty(&ln->cmpl_q))
+		return 0;
+
+	/* Wait until all active I/Os on this lnode are completed */
+	while (!list_empty(&ln->cmpl_q) && count--) {
+		spin_unlock_irq(&hw->lock);
+		msleep(CSIO_SCSI_ABORT_Q_POLL_MS);
+		spin_lock_irq(&hw->lock);
+	}
+
+	/* all I/Os completed */
+	if (list_empty(&ln->cmpl_q))
+		return 0;
+
+	csio_dbg(hw, "Some I/Os pending on ln:%p, aborting them..\n", ln);
+
+	/* I/Os are pending, abort them */
+	rv = csio_scsi_abort_io_q(scm, &ln->cmpl_q, 30000);
+	if (rv != 0) {
+		csio_dbg(hw, "Some I/O aborts timed out, cleaning up..\n");
+		csio_scsi_cleanup_io_q(scm, &ln->cmpl_q);
+	}
+
+	CSIO_DB_ASSERT(list_empty(&ln->cmpl_q));
+
+	return rv;
+}
+
+static ssize_t
+csio_show_hw_state(struct device *dev,
+		   struct device_attribute *attr, char *buf)
+{
+	struct csio_lnode *ln = shost_priv(class_to_shost(dev));
+	struct csio_hw *hw = csio_lnode_to_hw(ln);
+
+	if (csio_is_hw_ready(hw))
+		return snprintf(buf, PAGE_SIZE, "ready\n");
+	else
+		return snprintf(buf, PAGE_SIZE, "not ready\n");
+}
+
+/* Device reset */
+static ssize_t
+csio_device_reset(struct device *dev,
+		   struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct csio_lnode *ln = shost_priv(class_to_shost(dev));
+	struct csio_hw *hw = csio_lnode_to_hw(ln);
+
+	if (*buf != '1')
+		return -EINVAL;
+
+	/* Delete NPIV lnodes */
+	 csio_lnodes_exit(hw, 1);
+
+	/* Block upper IOs */
+	csio_lnodes_block_request(hw);
+
+	spin_lock_irq(&hw->lock);
+	csio_hw_reset(hw);
+	spin_unlock_irq(&hw->lock);
+
+	/* Unblock upper IOs */
+	csio_lnodes_unblock_request(hw);
+	return count;
+}
+
+/* disable port */
+static ssize_t
+csio_disable_port(struct device *dev,
+		   struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct csio_lnode *ln = shost_priv(class_to_shost(dev));
+	struct csio_hw *hw = csio_lnode_to_hw(ln);
+	bool disable;
+
+	if (*buf == '1' || *buf == '0')
+		disable = (*buf == '1') ? true : false;
+	else
+		return -EINVAL;
+
+	/* Block upper IOs */
+	csio_lnodes_block_by_port(hw, ln->portid);
+
+	spin_lock_irq(&hw->lock);
+	csio_disable_lnodes(hw, ln->portid, disable);
+	spin_unlock_irq(&hw->lock);
+
+	/* Unblock upper IOs */
+	csio_lnodes_unblock_by_port(hw, ln->portid);
+	return count;
+}
+
+/* Show debug level */
+static ssize_t
+csio_show_dbg_level(struct device *dev,
+		   struct device_attribute *attr, char *buf)
+{
+	struct csio_lnode *ln = shost_priv(class_to_shost(dev));
+
+	return snprintf(buf, PAGE_SIZE, "%x\n", ln->params.log_level);
+}
+
+/* Store debug level */
+static ssize_t
+csio_store_dbg_level(struct device *dev,
+		   struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct csio_lnode *ln = shost_priv(class_to_shost(dev));
+	struct csio_hw *hw = csio_lnode_to_hw(ln);
+	uint32_t dbg_level = 0;
+
+	if (!isdigit(buf[0]))
+		return -EINVAL;
+
+	if (sscanf(buf, "%i", &dbg_level))
+		return -EINVAL;
+
+	ln->params.log_level = dbg_level;
+	hw->params.log_level = dbg_level;
+
+	return 0;
+}
+
+static DEVICE_ATTR(hw_state, S_IRUGO, csio_show_hw_state, NULL);
+static DEVICE_ATTR(device_reset, S_IRUGO | S_IWUSR, NULL, csio_device_reset);
+static DEVICE_ATTR(disable_port, S_IRUGO | S_IWUSR, NULL, csio_disable_port);
+static DEVICE_ATTR(dbg_level, S_IRUGO | S_IWUSR, csio_show_dbg_level,
+		  csio_store_dbg_level);
+
+static struct device_attribute *csio_fcoe_lport_attrs[] = {
+	&dev_attr_hw_state,
+	&dev_attr_device_reset,
+	&dev_attr_disable_port,
+	&dev_attr_dbg_level,
+	NULL,
+};
+
+static ssize_t
+csio_show_num_reg_rnodes(struct device *dev,
+		     struct device_attribute *attr, char *buf)
+{
+	struct csio_lnode *ln = shost_priv(class_to_shost(dev));
+
+	return snprintf(buf, PAGE_SIZE, "%d\n", ln->num_reg_rnodes);
+}
+
+static DEVICE_ATTR(num_reg_rnodes, S_IRUGO, csio_show_num_reg_rnodes, NULL);
+
+static struct device_attribute *csio_fcoe_vport_attrs[] = {
+	&dev_attr_num_reg_rnodes,
+	&dev_attr_dbg_level,
+	NULL,
+};
+
+static inline uint32_t
+csio_scsi_copy_to_sgl(struct csio_hw *hw, struct csio_ioreq *req)
+{
+	struct scsi_cmnd *scmnd  = (struct scsi_cmnd *)csio_scsi_cmnd(req);
+	struct scatterlist *sg;
+	uint32_t bytes_left;
+	uint32_t bytes_copy;
+	uint32_t buf_off = 0;
+	uint32_t start_off = 0;
+	uint32_t sg_off = 0;
+	void *sg_addr;
+	void *buf_addr;
+	struct csio_dma_buf *dma_buf;
+
+	bytes_left = scsi_bufflen(scmnd);
+	sg = scsi_sglist(scmnd);
+	dma_buf = (struct csio_dma_buf *)csio_list_next(&req->gen_list);
+
+	/* Copy data from driver buffer to SGs of SCSI CMD */
+	while (bytes_left > 0 && sg && dma_buf) {
+		if (buf_off >= dma_buf->len) {
+			buf_off = 0;
+			dma_buf = (struct csio_dma_buf *)
+					csio_list_next(dma_buf);
+			continue;
+		}
+
+		if (start_off >= sg->length) {
+			start_off -= sg->length;
+			sg = sg_next(sg);
+			continue;
+		}
+
+		buf_addr = dma_buf->vaddr + buf_off;
+		sg_off = sg->offset + start_off;
+		bytes_copy = min((dma_buf->len - buf_off),
+				sg->length - start_off);
+		bytes_copy = min((uint32_t)(PAGE_SIZE - (sg_off & ~PAGE_MASK)),
+				 bytes_copy);
+
+		sg_addr = kmap_atomic(sg_page(sg) + (sg_off >> PAGE_SHIFT));
+		if (!sg_addr) {
+			csio_err(hw, "failed to kmap sg:%p of ioreq:%p\n",
+				sg, req);
+			break;
+		}
+
+		csio_dbg(hw, "copy_to_sgl:sg_addr %p sg_off %d buf %p len %d\n",
+				sg_addr, sg_off, buf_addr, bytes_copy);
+		memcpy(sg_addr + (sg_off & ~PAGE_MASK), buf_addr, bytes_copy);
+		kunmap_atomic(sg_addr);
+
+		start_off +=  bytes_copy;
+		buf_off += bytes_copy;
+		bytes_left -= bytes_copy;
+	}
+
+	if (bytes_left > 0)
+		return DID_ERROR;
+	else
+		return DID_OK;
+}
+
+/*
+ * csio_scsi_err_handler - SCSI error handler.
+ * @hw: HW module.
+ * @req: IO request.
+ *
+ */
+static inline void
+csio_scsi_err_handler(struct csio_hw *hw, struct csio_ioreq *req)
+{
+	struct scsi_cmnd *cmnd  = (struct scsi_cmnd *)csio_scsi_cmnd(req);
+	struct csio_scsim *scm = csio_hw_to_scsim(hw);
+	struct fcp_resp_with_ext *fcp_resp;
+	struct fcp_resp_rsp_info *rsp_info;
+	struct csio_dma_buf *dma_buf;
+	uint8_t flags, scsi_status = 0;
+	uint32_t host_status = DID_OK;
+	uint32_t rsp_len = 0, sns_len = 0;
+	struct csio_rnode *rn = (struct csio_rnode *)(cmnd->device->hostdata);
+
+
+	switch (req->wr_status) {
+	case FW_HOSTERROR:
+		if (unlikely(!csio_is_hw_ready(hw)))
+			return;
+
+		host_status = DID_ERROR;
+		CSIO_INC_STATS(scm, n_hosterror);
+
+		break;
+	case FW_SCSI_RSP_ERR:
+		dma_buf = &req->dma_buf;
+		fcp_resp = (struct fcp_resp_with_ext *)dma_buf->vaddr;
+		rsp_info = (struct fcp_resp_rsp_info *)(fcp_resp + 1);
+		flags = fcp_resp->resp.fr_flags;
+		scsi_status = fcp_resp->resp.fr_status;
+
+		if (flags & FCP_RSP_LEN_VAL) {
+			rsp_len = be32_to_cpu(fcp_resp->ext.fr_rsp_len);
+			if ((rsp_len != 0 && rsp_len != 4 && rsp_len != 8) ||
+				(rsp_info->rsp_code != FCP_TMF_CMPL)) {
+				host_status = DID_ERROR;
+				goto out;
+			}
+		}
+
+		if ((flags & FCP_SNS_LEN_VAL) && fcp_resp->ext.fr_sns_len) {
+			sns_len = be32_to_cpu(fcp_resp->ext.fr_sns_len);
+			if (sns_len > SCSI_SENSE_BUFFERSIZE)
+				sns_len = SCSI_SENSE_BUFFERSIZE;
+
+			memcpy(cmnd->sense_buffer,
+			       &rsp_info->_fr_resvd[0] + rsp_len, sns_len);
+			CSIO_INC_STATS(scm, n_autosense);
+		}
+
+		scsi_set_resid(cmnd, 0);
+
+		/* Under run */
+		if (flags & FCP_RESID_UNDER) {
+			scsi_set_resid(cmnd,
+				       be32_to_cpu(fcp_resp->ext.fr_resid));
+
+			if (!(flags & FCP_SNS_LEN_VAL) &&
+			    (scsi_status == SAM_STAT_GOOD) &&
+			    ((scsi_bufflen(cmnd) - scsi_get_resid(cmnd))
+							< cmnd->underflow))
+				host_status = DID_ERROR;
+		} else if (flags & FCP_RESID_OVER)
+			host_status = DID_ERROR;
+
+		CSIO_INC_STATS(scm, n_rsperror);
+		break;
+
+	case FW_SCSI_OVER_FLOW_ERR:
+		csio_warn(hw,
+			  "Over-flow error,cmnd:0x%x expected len:0x%x"
+			  " resid:0x%x\n", cmnd->cmnd[0],
+			  scsi_bufflen(cmnd), scsi_get_resid(cmnd));
+		host_status = DID_ERROR;
+		CSIO_INC_STATS(scm, n_ovflerror);
+		break;
+
+	case FW_SCSI_UNDER_FLOW_ERR:
+		csio_warn(hw,
+			  "Under-flow error,cmnd:0x%x expected"
+			  " len:0x%x resid:0x%x lun:0x%x ssn:0x%x\n",
+			  cmnd->cmnd[0], scsi_bufflen(cmnd),
+			  scsi_get_resid(cmnd), cmnd->device->lun,
+			  rn->flowid);
+		host_status = DID_ERROR;
+		CSIO_INC_STATS(scm, n_unflerror);
+		break;
+
+	case FW_SCSI_ABORT_REQUESTED:
+	case FW_SCSI_ABORTED:
+	case FW_SCSI_CLOSE_REQUESTED:
+		csio_dbg(hw, "Req %p cmd:%p op:%x %s\n", req, cmnd,
+			     cmnd->cmnd[0],
+			    (req->wr_status == FW_SCSI_CLOSE_REQUESTED) ?
+			    "closed" : "aborted");
+		/*
+		 * csio_eh_abort_handler checks this value to
+		 * succeed or fail the abort request.
+		 */
+		host_status = DID_REQUEUE;
+		if (req->wr_status == FW_SCSI_CLOSE_REQUESTED)
+			CSIO_INC_STATS(scm, n_closed);
+		else
+			CSIO_INC_STATS(scm, n_aborted);
+		break;
+
+	case FW_SCSI_ABORT_TIMEDOUT:
+		/* FW timed out the abort itself */
+		csio_dbg(hw, "FW timed out abort req:%p cmnd:%p status:%x\n",
+			 req, cmnd, req->wr_status);
+		host_status = DID_ERROR;
+		CSIO_INC_STATS(scm, n_abrt_timedout);
+		break;
+
+	case FW_RDEV_NOT_READY:
+		/*
+		 * In firmware, a RDEV can get into this state
+		 * temporarily, before moving into dissapeared/lost
+		 * state. So, the driver should complete the request equivalent
+		 * to device-disappeared!
+		 */
+		CSIO_INC_STATS(scm, n_rdev_nr_error);
+		host_status = DID_ERROR;
+		break;
+
+	case FW_ERR_RDEV_LOST:
+		CSIO_INC_STATS(scm, n_rdev_lost_error);
+		host_status = DID_ERROR;
+		break;
+
+	case FW_ERR_RDEV_LOGO:
+		CSIO_INC_STATS(scm, n_rdev_logo_error);
+		host_status = DID_ERROR;
+		break;
+
+	case FW_ERR_RDEV_IMPL_LOGO:
+		host_status = DID_ERROR;
+		break;
+
+	case FW_ERR_LINK_DOWN:
+		CSIO_INC_STATS(scm, n_link_down_error);
+		host_status = DID_ERROR;
+		break;
+
+	case FW_FCOE_NO_XCHG:
+		CSIO_INC_STATS(scm, n_no_xchg_error);
+		host_status = DID_ERROR;
+		break;
+
+	default:
+		csio_err(hw, "Unknown SCSI FW WR status:%d req:%p cmnd:%p\n",
+			    req->wr_status, req, cmnd);
+		CSIO_DB_ASSERT(0);
+
+		CSIO_INC_STATS(scm, n_unknown_error);
+		host_status = DID_ERROR;
+		break;
+	}
+
+out:
+	if (req->nsge > 0)
+		scsi_dma_unmap(cmnd);
+
+	cmnd->result = (((host_status) << 16) | scsi_status);
+	cmnd->scsi_done(cmnd);
+
+	/* Wake up waiting threads */
+	csio_scsi_cmnd(req) = NULL;
+	complete_all(&req->cmplobj);
+}
+
+/*
+ * csio_scsi_cbfn - SCSI callback function.
+ * @hw: HW module.
+ * @req: IO request.
+ *
+ */
+static void
+csio_scsi_cbfn(struct csio_hw *hw, struct csio_ioreq *req)
+{
+	struct scsi_cmnd *cmnd  = (struct scsi_cmnd *)csio_scsi_cmnd(req);
+	uint8_t scsi_status = SAM_STAT_GOOD;
+	uint32_t host_status = DID_OK;
+
+	if (likely(req->wr_status == FW_SUCCESS)) {
+		if (req->nsge > 0) {
+			scsi_dma_unmap(cmnd);
+			if (req->dcopy)
+				host_status = csio_scsi_copy_to_sgl(hw, req);
+		}
+
+		cmnd->result = (((host_status) << 16) | scsi_status);
+		cmnd->scsi_done(cmnd);
+		csio_scsi_cmnd(req) = NULL;
+		CSIO_INC_STATS(csio_hw_to_scsim(hw), n_tot_success);
+	} else {
+		/* Error handling */
+		csio_scsi_err_handler(hw, req);
+	}
+}
+
+/**
+ * csio_queuecommand - Entry point to kickstart an I/O request.
+ * @host:	The scsi_host pointer.
+ * @cmnd:	The I/O request from ML.
+ *
+ * This routine does the following:
+ *	- Checks for HW and Rnode module readiness.
+ *	- Gets a free ioreq structure (which is already initialized
+ *	  to uninit during its allocation).
+ *	- Maps SG elements.
+ *	- Initializes ioreq members.
+ *	- Kicks off the SCSI state machine for this IO.
+ *	- Returns busy status on error.
+ */
+static int
+csio_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmnd)
+{
+	struct csio_lnode *ln = shost_priv(host);
+	struct csio_hw *hw = csio_lnode_to_hw(ln);
+	struct csio_scsim *scsim = csio_hw_to_scsim(hw);
+	struct csio_rnode *rn = (struct csio_rnode *)(cmnd->device->hostdata);
+	struct csio_ioreq *ioreq = NULL;
+	unsigned long flags;
+	int nsge = 0;
+	int rv = SCSI_MLQUEUE_HOST_BUSY, nr;
+	int retval;
+	int cpu;
+	struct csio_scsi_qset *sqset;
+	struct fc_rport *rport = starget_to_rport(scsi_target(cmnd->device));
+
+	if (!blk_rq_cpu_valid(cmnd->request))
+		cpu = smp_processor_id();
+	else
+		cpu = cmnd->request->cpu;
+
+	sqset = &hw->sqset[ln->portid][cpu];
+
+	nr = fc_remote_port_chkready(rport);
+	if (nr) {
+		cmnd->result = nr;
+		CSIO_INC_STATS(scsim, n_rn_nr_error);
+		goto err_done;
+	}
+
+	if (unlikely(!csio_is_hw_ready(hw))) {
+		cmnd->result = (DID_REQUEUE << 16);
+		CSIO_INC_STATS(scsim, n_hw_nr_error);
+		goto err_done;
+	}
+
+	/* Get req->nsge, if there are SG elements to be mapped  */
+	nsge = scsi_dma_map(cmnd);
+	if (unlikely(nsge < 0)) {
+		CSIO_INC_STATS(scsim, n_dmamap_error);
+		goto err;
+	}
+
+	/* Do we support so many mappings? */
+	if (unlikely(nsge > scsim->max_sge)) {
+		csio_warn(hw,
+			  "More SGEs than can be supported."
+			  " SGEs: %d, Max SGEs: %d\n", nsge, scsim->max_sge);
+		CSIO_INC_STATS(scsim, n_unsupp_sge_error);
+		goto err_dma_unmap;
+	}
+
+	/* Get a free ioreq structure - SM is already set to uninit */
+	ioreq = csio_get_scsi_ioreq_lock(hw, scsim);
+	if (!ioreq) {
+		csio_err(hw, "Out of I/O request elements. Active #:%d\n",
+			 scsim->stats.n_active);
+		CSIO_INC_STATS(scsim, n_no_req_error);
+		goto err_dma_unmap;
+	}
+
+	ioreq->nsge		= nsge;
+	ioreq->lnode		= ln;
+	ioreq->rnode		= rn;
+	ioreq->iq_idx		= sqset->iq_idx;
+	ioreq->eq_idx		= sqset->eq_idx;
+	ioreq->wr_status	= 0;
+	ioreq->drv_status	= 0;
+	csio_scsi_cmnd(ioreq)	= (void *)cmnd;
+	ioreq->tmo		= 0;
+	ioreq->datadir		= cmnd->sc_data_direction;
+
+	if (cmnd->sc_data_direction == DMA_TO_DEVICE) {
+		CSIO_INC_STATS(ln, n_output_requests);
+		ln->stats.n_output_bytes += scsi_bufflen(cmnd);
+	} else if (cmnd->sc_data_direction == DMA_FROM_DEVICE) {
+		CSIO_INC_STATS(ln, n_input_requests);
+		ln->stats.n_input_bytes += scsi_bufflen(cmnd);
+	} else
+		CSIO_INC_STATS(ln, n_control_requests);
+
+	/* Set cbfn */
+	ioreq->io_cbfn = csio_scsi_cbfn;
+
+	/* Needed during abort */
+	cmnd->host_scribble = (unsigned char *)ioreq;
+	cmnd->SCp.Message = 0;
+
+	/* Kick off SCSI IO SM on the ioreq */
+	spin_lock_irqsave(&hw->lock, flags);
+	retval = csio_scsi_start_io(ioreq);
+	spin_unlock_irqrestore(&hw->lock, flags);
+
+	if (retval != 0) {
+		csio_err(hw, "ioreq: %p couldnt be started, status:%d\n",
+			 ioreq, retval);
+		CSIO_INC_STATS(scsim, n_busy_error);
+		goto err_put_req;
+	}
+
+	return 0;
+
+err_put_req:
+	csio_put_scsi_ioreq_lock(hw, scsim, ioreq);
+err_dma_unmap:
+	if (nsge > 0)
+		scsi_dma_unmap(cmnd);
+err:
+	return rv;
+
+err_done:
+	cmnd->scsi_done(cmnd);
+	return 0;
+}
+
+static int
+csio_do_abrt_cls(struct csio_hw *hw, struct csio_ioreq *ioreq, bool abort)
+{
+	int rv;
+	int cpu = smp_processor_id();
+	struct csio_lnode *ln = ioreq->lnode;
+	struct csio_scsi_qset *sqset = &hw->sqset[ln->portid][cpu];
+
+	ioreq->tmo = CSIO_SCSI_ABRT_TMO_MS;
+	/*
+	 * Use current processor queue for posting the abort/close, but retain
+	 * the ingress queue ID of the original I/O being aborted/closed - we
+	 * need the abort/close completion to be received on the same queue
+	 * as the original I/O.
+	 */
+	ioreq->eq_idx = sqset->eq_idx;
+
+	if (abort == SCSI_ABORT)
+		rv = csio_scsi_abort(ioreq);
+	else
+		rv = csio_scsi_close(ioreq);
+
+	return rv;
+}
+
+static int
+csio_eh_abort_handler(struct scsi_cmnd *cmnd)
+{
+	struct csio_ioreq *ioreq;
+	struct csio_lnode *ln = shost_priv(cmnd->device->host);
+	struct csio_hw *hw = csio_lnode_to_hw(ln);
+	struct csio_scsim *scsim = csio_hw_to_scsim(hw);
+	int ready = 0, ret;
+	unsigned long tmo = 0;
+	int rv;
+	struct csio_rnode *rn = (struct csio_rnode *)(cmnd->device->hostdata);
+
+	ret = fc_block_scsi_eh(cmnd);
+	if (ret)
+		return ret;
+
+	ioreq = (struct csio_ioreq *)cmnd->host_scribble;
+	if (!ioreq)
+		return SUCCESS;
+
+	if (!rn)
+		return FAILED;
+
+	csio_dbg(hw,
+		 "Request to abort ioreq:%p cmd:%p cdb:%08llx"
+		 " ssni:0x%x lun:%d iq:0x%x\n",
+		ioreq, cmnd, *((uint64_t *)cmnd->cmnd), rn->flowid,
+		cmnd->device->lun, csio_q_physiqid(hw, ioreq->iq_idx));
+
+	if (((struct scsi_cmnd *)csio_scsi_cmnd(ioreq)) != cmnd) {
+		CSIO_INC_STATS(scsim, n_abrt_race_comp);
+		return SUCCESS;
+	}
+
+	ready = csio_is_lnode_ready(ln);
+	tmo = CSIO_SCSI_ABRT_TMO_MS;
+
+	spin_lock_irq(&hw->lock);
+	rv = csio_do_abrt_cls(hw, ioreq, (ready ? SCSI_ABORT : SCSI_CLOSE));
+	spin_unlock_irq(&hw->lock);
+
+	if (rv != 0) {
+		if (rv == -EINVAL) {
+			/* Return success, if abort/close request issued on
+			 * already completed IO
+			 */
+			return SUCCESS;
+		}
+		if (ready)
+			CSIO_INC_STATS(scsim, n_abrt_busy_error);
+		else
+			CSIO_INC_STATS(scsim, n_cls_busy_error);
+
+		goto inval_scmnd;
+	}
+
+	/* Wait for completion */
+	init_completion(&ioreq->cmplobj);
+	wait_for_completion_timeout(&ioreq->cmplobj, msecs_to_jiffies(tmo));
+
+	/* FW didnt respond to abort within our timeout */
+	if (((struct scsi_cmnd *)csio_scsi_cmnd(ioreq)) == cmnd) {
+
+		csio_err(hw, "Abort timed out -- req: %p\n", ioreq);
+		CSIO_INC_STATS(scsim, n_abrt_timedout);
+
+inval_scmnd:
+		if (ioreq->nsge > 0)
+			scsi_dma_unmap(cmnd);
+
+		spin_lock_irq(&hw->lock);
+		csio_scsi_cmnd(ioreq) = NULL;
+		spin_unlock_irq(&hw->lock);
+
+		cmnd->result = (DID_ERROR << 16);
+		cmnd->scsi_done(cmnd);
+
+		return FAILED;
+	}
+
+	/* FW successfully aborted the request */
+	if (host_byte(cmnd->result) == DID_REQUEUE) {
+		csio_info(hw,
+			"Aborted SCSI command to (%d:%d) serial#:0x%lx\n",
+			cmnd->device->id, cmnd->device->lun,
+			cmnd->serial_number);
+		return SUCCESS;
+	} else {
+		csio_info(hw,
+			"Failed to abort SCSI command, (%d:%d) serial#:0x%lx\n",
+			cmnd->device->id, cmnd->device->lun,
+			cmnd->serial_number);
+		return FAILED;
+	}
+}
+
+/*
+ * csio_tm_cbfn - TM callback function.
+ * @hw: HW module.
+ * @req: IO request.
+ *
+ * Cache the result in 'cmnd', since ioreq will be freed soon
+ * after we return from here, and the waiting thread shouldnt trust
+ * the ioreq contents.
+ */
+static void
+csio_tm_cbfn(struct csio_hw *hw, struct csio_ioreq *req)
+{
+	struct scsi_cmnd *cmnd  = (struct scsi_cmnd *)csio_scsi_cmnd(req);
+	struct csio_dma_buf *dma_buf;
+	uint8_t flags = 0;
+	struct fcp_resp_with_ext *fcp_resp;
+	struct fcp_resp_rsp_info *rsp_info;
+
+	csio_dbg(hw, "req: %p in csio_tm_cbfn status: %d\n",
+		      req, req->wr_status);
+
+	/* Cache FW return status */
+	cmnd->SCp.Status = req->wr_status;
+
+	/* Special handling based on FCP response */
+
+	/*
+	 * FW returns us this error, if flags were set. FCP4 says
+	 * FCP_RSP_LEN_VAL in flags shall be set for TM completions.
+	 * So if a target were to set this bit, we expect that the
+	 * rsp_code is set to FCP_TMF_CMPL for a successful TM
+	 * completion. Any other rsp_code means TM operation failed.
+	 * If a target were to just ignore setting flags, we treat
+	 * the TM operation as success, and FW returns FW_SUCCESS.
+	 */
+	if (req->wr_status == FW_SCSI_RSP_ERR) {
+		dma_buf = &req->dma_buf;
+		fcp_resp = (struct fcp_resp_with_ext *)dma_buf->vaddr;
+		rsp_info = (struct fcp_resp_rsp_info *)(fcp_resp + 1);
+
+		flags = fcp_resp->resp.fr_flags;
+
+		/* Modify return status if flags indicate success */
+		if (flags & FCP_RSP_LEN_VAL)
+			if (rsp_info->rsp_code == FCP_TMF_CMPL)
+				cmnd->SCp.Status = FW_SUCCESS;
+
+		csio_dbg(hw, "TM FCP rsp code: %d\n", rsp_info->rsp_code);
+	}
+
+	/* Wake up the TM handler thread */
+	csio_scsi_cmnd(req) = NULL;
+}
+
+static int
+csio_eh_lun_reset_handler(struct scsi_cmnd *cmnd)
+{
+	struct csio_lnode *ln = shost_priv(cmnd->device->host);
+	struct csio_hw *hw = csio_lnode_to_hw(ln);
+	struct csio_scsim *scsim = csio_hw_to_scsim(hw);
+	struct csio_rnode *rn = (struct csio_rnode *)(cmnd->device->hostdata);
+	struct csio_ioreq *ioreq = NULL;
+	struct csio_scsi_qset *sqset;
+	unsigned long flags;
+	int retval;
+	int count, ret;
+	LIST_HEAD(local_q);
+	struct csio_scsi_level_data sld;
+
+	if (!rn)
+		goto fail;
+
+	csio_dbg(hw, "Request to reset LUN:%d (ssni:0x%x tgtid:%d)\n",
+		      cmnd->device->lun, rn->flowid, rn->scsi_id);
+
+	if (!csio_is_lnode_ready(ln)) {
+		csio_err(hw,
+			 "LUN reset cannot be issued on non-ready"
+			 " local node vnpi:0x%x (LUN:%d)\n",
+			 ln->vnp_flowid, cmnd->device->lun);
+		goto fail;
+	}
+
+	/* Lnode is ready, now wait on rport node readiness */
+	ret = fc_block_scsi_eh(cmnd);
+	if (ret)
+		return ret;
+
+	/*
+	 * If we have blocked in the previous call, at this point, either the
+	 * remote node has come back online, or device loss timer has fired
+	 * and the remote node is destroyed. Allow the LUN reset only for
+	 * the former case, since LUN reset is a TMF I/O on the wire, and we
+	 * need a valid session to issue it.
+	 */
+	if (fc_remote_port_chkready(rn->rport)) {
+		csio_err(hw,
+			 "LUN reset cannot be issued on non-ready"
+			 " remote node ssni:0x%x (LUN:%d)\n",
+			 rn->flowid, cmnd->device->lun);
+		goto fail;
+	}
+
+	/* Get a free ioreq structure - SM is already set to uninit */
+	ioreq = csio_get_scsi_ioreq_lock(hw, scsim);
+
+	if (!ioreq) {
+		csio_err(hw, "Out of IO request elements. Active # :%d\n",
+			 scsim->stats.n_active);
+		goto fail;
+	}
+
+	sqset			= &hw->sqset[ln->portid][smp_processor_id()];
+	ioreq->nsge		= 0;
+	ioreq->lnode		= ln;
+	ioreq->rnode		= rn;
+	ioreq->iq_idx		= sqset->iq_idx;
+	ioreq->eq_idx		= sqset->eq_idx;
+
+	csio_scsi_cmnd(ioreq)	= cmnd;
+	cmnd->host_scribble	= (unsigned char *)ioreq;
+	cmnd->SCp.Status	= 0;
+
+	cmnd->SCp.Message	= FCP_TMF_LUN_RESET;
+	ioreq->tmo		= CSIO_SCSI_LUNRST_TMO_MS / 1000;
+
+	/*
+	 * FW times the LUN reset for ioreq->tmo, so we got to wait a little
+	 * longer (10s for now) than that to allow FW to return the timed
+	 * out command.
+	 */
+	count = DIV_ROUND_UP((ioreq->tmo + 10) * 1000, CSIO_SCSI_TM_POLL_MS);
+
+	/* Set cbfn */
+	ioreq->io_cbfn = csio_tm_cbfn;
+
+	/* Save of the ioreq info for later use */
+	sld.level = CSIO_LEV_LUN;
+	sld.lnode = ioreq->lnode;
+	sld.rnode = ioreq->rnode;
+	sld.oslun = (uint64_t)cmnd->device->lun;
+
+	spin_lock_irqsave(&hw->lock, flags);
+	/* Kick off TM SM on the ioreq */
+	retval = csio_scsi_start_tm(ioreq);
+	spin_unlock_irqrestore(&hw->lock, flags);
+
+	if (retval != 0) {
+		csio_err(hw, "Failed to issue LUN reset, req:%p, status:%d\n",
+			    ioreq, retval);
+		goto fail_ret_ioreq;
+	}
+
+	csio_dbg(hw, "Waiting max %d secs for LUN reset completion\n",
+		    count * (CSIO_SCSI_TM_POLL_MS / 1000));
+	/* Wait for completion */
+	while ((((struct scsi_cmnd *)csio_scsi_cmnd(ioreq)) == cmnd)
+								&& count--)
+		msleep(CSIO_SCSI_TM_POLL_MS);
+
+	/* LUN reset timed-out */
+	if (((struct scsi_cmnd *)csio_scsi_cmnd(ioreq)) == cmnd) {
+		csio_err(hw, "LUN reset (%d:%d) timed out\n",
+			 cmnd->device->id, cmnd->device->lun);
+
+		spin_lock_irq(&hw->lock);
+		csio_scsi_drvcleanup(ioreq);
+		list_del_init(&ioreq->sm.sm_list);
+		spin_unlock_irq(&hw->lock);
+
+		goto fail_ret_ioreq;
+	}
+
+	/* LUN reset returned, check cached status */
+	if (cmnd->SCp.Status != FW_SUCCESS) {
+		csio_err(hw, "LUN reset failed (%d:%d), status: %d\n",
+			 cmnd->device->id, cmnd->device->lun, cmnd->SCp.Status);
+		goto fail;
+	}
+
+	/* LUN reset succeeded, Start aborting affected I/Os */
+	/*
+	 * Since the host guarantees during LUN reset that there
+	 * will not be any more I/Os to that LUN, until the LUN reset
+	 * completes, we gather pending I/Os after the LUN reset.
+	 */
+	spin_lock_irq(&hw->lock);
+	csio_scsi_gather_active_ios(scsim, &sld, &local_q);
+
+	retval = csio_scsi_abort_io_q(scsim, &local_q, 30000);
+	spin_unlock_irq(&hw->lock);
+
+	/* Aborts may have timed out */
+	if (retval != 0) {
+		csio_err(hw,
+			 "Attempt to abort I/Os during LUN reset of %d"
+			 " returned %d\n", cmnd->device->lun, retval);
+		/* Return I/Os back to active_q */
+		spin_lock_irq(&hw->lock);
+		list_splice_tail_init(&local_q, &scsim->active_q);
+		spin_unlock_irq(&hw->lock);
+		goto fail;
+	}
+
+	CSIO_INC_STATS(rn, n_lun_rst);
+
+	csio_info(hw, "LUN reset occurred (%d:%d)\n",
+		  cmnd->device->id, cmnd->device->lun);
+
+	return SUCCESS;
+
+fail_ret_ioreq:
+	csio_put_scsi_ioreq_lock(hw, scsim, ioreq);
+fail:
+	CSIO_INC_STATS(rn, n_lun_rst_fail);
+	return FAILED;
+}
+
+static int
+csio_slave_alloc(struct scsi_device *sdev)
+{
+	struct fc_rport *rport = starget_to_rport(scsi_target(sdev));
+
+	if (!rport || fc_remote_port_chkready(rport))
+		return -ENXIO;
+
+	sdev->hostdata = *((struct csio_lnode **)(rport->dd_data));
+
+	return 0;
+}
+
+static int
+csio_slave_configure(struct scsi_device *sdev)
+{
+	if (sdev->tagged_supported)
+		scsi_activate_tcq(sdev, csio_lun_qdepth);
+	else
+		scsi_deactivate_tcq(sdev, csio_lun_qdepth);
+
+	return 0;
+}
+
+static void
+csio_slave_destroy(struct scsi_device *sdev)
+{
+	sdev->hostdata = NULL;
+}
+
+static int
+csio_scan_finished(struct Scsi_Host *shost, unsigned long time)
+{
+	struct csio_lnode *ln = shost_priv(shost);
+	int rv = 1;
+
+	spin_lock_irq(shost->host_lock);
+	if (!ln->hwp || csio_list_deleted(&ln->sm.sm_list))
+		goto out;
+
+	rv = csio_scan_done(ln, jiffies, time, csio_max_scan_tmo * HZ,
+			    csio_delta_scan_tmo * HZ);
+out:
+	spin_unlock_irq(shost->host_lock);
+
+	return rv;
+}
+
+struct scsi_host_template csio_fcoe_shost_template = {
+	.module			= THIS_MODULE,
+	.name			= CSIO_DRV_DESC,
+	.proc_name		= KBUILD_MODNAME,
+	.queuecommand		= csio_queuecommand,
+	.eh_abort_handler	= csio_eh_abort_handler,
+	.eh_device_reset_handler = csio_eh_lun_reset_handler,
+	.slave_alloc		= csio_slave_alloc,
+	.slave_configure	= csio_slave_configure,
+	.slave_destroy		= csio_slave_destroy,
+	.scan_finished		= csio_scan_finished,
+	.this_id		= -1,
+	.sg_tablesize		= CSIO_SCSI_MAX_SGE,
+	.cmd_per_lun		= CSIO_MAX_CMD_PER_LUN,
+	.use_clustering		= ENABLE_CLUSTERING,
+	.shost_attrs		= csio_fcoe_lport_attrs,
+	.max_sectors		= CSIO_MAX_SECTOR_SIZE,
+};
+
+struct scsi_host_template csio_fcoe_shost_vport_template = {
+	.module			= THIS_MODULE,
+	.name			= CSIO_DRV_DESC,
+	.proc_name		= KBUILD_MODNAME,
+	.queuecommand		= csio_queuecommand,
+	.eh_abort_handler	= csio_eh_abort_handler,
+	.eh_device_reset_handler = csio_eh_lun_reset_handler,
+	.slave_alloc		= csio_slave_alloc,
+	.slave_configure	= csio_slave_configure,
+	.slave_destroy		= csio_slave_destroy,
+	.scan_finished		= csio_scan_finished,
+	.this_id		= -1,
+	.sg_tablesize		= CSIO_SCSI_MAX_SGE,
+	.cmd_per_lun		= CSIO_MAX_CMD_PER_LUN,
+	.use_clustering		= ENABLE_CLUSTERING,
+	.shost_attrs		= csio_fcoe_vport_attrs,
+	.max_sectors		= CSIO_MAX_SECTOR_SIZE,
+};
+
+/*
+ * csio_scsi_alloc_ddp_bufs - Allocate buffers for DDP of unaligned SGLs.
+ * @scm: SCSI Module
+ * @hw: HW device.
+ * @buf_size: buffer size
+ * @num_buf : Number of buffers.
+ *
+ * This routine allocates DMA buffers required for SCSI Data xfer, if
+ * each SGL buffer for a SCSI Read request posted by SCSI midlayer are
+ * not virtually contiguous.
+ */
+static int
+csio_scsi_alloc_ddp_bufs(struct csio_scsim *scm, struct csio_hw *hw,
+			 int buf_size, int num_buf)
+{
+	int n = 0;
+	struct list_head *tmp;
+	struct csio_dma_buf *ddp_desc = NULL;
+	uint32_t unit_size = 0;
+
+	if (!num_buf)
+		return 0;
+
+	if (!buf_size)
+		return -EINVAL;
+
+	INIT_LIST_HEAD(&scm->ddp_freelist);
+
+	/* Align buf size to page size */
+	buf_size = (buf_size + PAGE_SIZE - 1) & PAGE_MASK;
+	/* Initialize dma descriptors */
+	for (n = 0; n < num_buf; n++) {
+		/* Set unit size to request size */
+		unit_size = buf_size;
+		ddp_desc = kzalloc(sizeof(struct csio_dma_buf), GFP_KERNEL);
+		if (!ddp_desc) {
+			csio_err(hw,
+				 "Failed to allocate ddp descriptors,"
+				 " Num allocated = %d.\n",
+				 scm->stats.n_free_ddp);
+			goto no_mem;
+		}
+
+		/* Allocate Dma buffers for DDP */
+		ddp_desc->vaddr = pci_alloc_consistent(hw->pdev, unit_size,
+							&ddp_desc->paddr);
+		if (!ddp_desc->vaddr) {
+			csio_err(hw,
+				 "SCSI response DMA buffer (ddp) allocation"
+				 " failed!\n");
+			kfree(ddp_desc);
+			goto no_mem;
+		}
+
+		ddp_desc->len = unit_size;
+
+		/* Added it to scsi ddp freelist */
+		list_add_tail(&ddp_desc->list, &scm->ddp_freelist);
+		CSIO_INC_STATS(scm, n_free_ddp);
+	}
+
+	return 0;
+no_mem:
+	/* release dma descs back to freelist and free dma memory */
+	list_for_each(tmp, &scm->ddp_freelist) {
+		ddp_desc = (struct csio_dma_buf *) tmp;
+		tmp = csio_list_prev(tmp);
+		pci_free_consistent(hw->pdev, ddp_desc->len, ddp_desc->vaddr,
+				    ddp_desc->paddr);
+		list_del_init(&ddp_desc->list);
+		kfree(ddp_desc);
+	}
+	scm->stats.n_free_ddp = 0;
+
+	return -ENOMEM;
+}
+
+/*
+ * csio_scsi_free_ddp_bufs - free DDP buffers of unaligned SGLs.
+ * @scm: SCSI Module
+ * @hw: HW device.
+ *
+ * This routine frees ddp buffers.
+ */
+static void
+csio_scsi_free_ddp_bufs(struct csio_scsim *scm, struct csio_hw *hw)
+{
+	struct list_head *tmp;
+	struct csio_dma_buf *ddp_desc;
+
+	/* release dma descs back to freelist and free dma memory */
+	list_for_each(tmp, &scm->ddp_freelist) {
+		ddp_desc = (struct csio_dma_buf *) tmp;
+		tmp = csio_list_prev(tmp);
+		pci_free_consistent(hw->pdev, ddp_desc->len, ddp_desc->vaddr,
+				    ddp_desc->paddr);
+		list_del_init(&ddp_desc->list);
+		kfree(ddp_desc);
+	}
+	scm->stats.n_free_ddp = 0;
+}
+
+/**
+ * csio_scsim_init - Initialize SCSI Module
+ * @scm:	SCSI Module
+ * @hw:		HW module
+ *
+ */
+int
+csio_scsim_init(struct csio_scsim *scm, struct csio_hw *hw)
+{
+	int i;
+	struct csio_ioreq *ioreq;
+	struct csio_dma_buf *dma_buf;
+
+	INIT_LIST_HEAD(&scm->active_q);
+	scm->hw = hw;
+
+	scm->proto_cmd_len = sizeof(struct fcp_cmnd);
+	scm->proto_rsp_len = CSIO_SCSI_RSP_LEN;
+	scm->max_sge = CSIO_SCSI_MAX_SGE;
+
+	spin_lock_init(&scm->freelist_lock);
+
+	/* Pre-allocate ioreqs and initialize them */
+	INIT_LIST_HEAD(&scm->ioreq_freelist);
+	for (i = 0; i < csio_scsi_ioreqs; i++) {
+
+		ioreq = kzalloc(sizeof(struct csio_ioreq), GFP_KERNEL);
+		if (!ioreq) {
+			csio_err(hw,
+				 "I/O request element allocation failed, "
+				 " Num allocated = %d.\n",
+				 scm->stats.n_free_ioreq);
+
+			goto free_ioreq;
+		}
+
+		/* Allocate Dma buffers for Response Payload */
+		dma_buf = &ioreq->dma_buf;
+		dma_buf->vaddr = pci_pool_alloc(hw->scsi_pci_pool, GFP_KERNEL,
+						&dma_buf->paddr);
+		if (!dma_buf->vaddr) {
+			csio_err(hw,
+				 "SCSI response DMA buffer allocation"
+				 " failed!\n");
+			kfree(ioreq);
+			goto free_ioreq;
+		}
+
+		dma_buf->len = scm->proto_rsp_len;
+
+		/* Set state to uninit */
+		csio_init_state(&ioreq->sm, csio_scsis_uninit);
+		INIT_LIST_HEAD(&ioreq->gen_list);
+		init_completion(&ioreq->cmplobj);
+
+		list_add_tail(&ioreq->sm.sm_list, &scm->ioreq_freelist);
+		CSIO_INC_STATS(scm, n_free_ioreq);
+	}
+
+	if (csio_scsi_alloc_ddp_bufs(scm, hw, PAGE_SIZE, csio_ddp_descs))
+		goto free_ioreq;
+
+	return 0;
+
+free_ioreq:
+	/*
+	 * Free up existing allocations, since an error
+	 * from here means we are returning for good
+	 */
+	while (!list_empty(&scm->ioreq_freelist)) {
+		struct csio_sm *tmp;
+
+		tmp = list_first_entry(&scm->ioreq_freelist,
+				       struct csio_sm, sm_list);
+		list_del_init(&tmp->sm_list);
+		ioreq = (struct csio_ioreq *)tmp;
+
+		dma_buf = &ioreq->dma_buf;
+		pci_pool_free(hw->scsi_pci_pool, dma_buf->vaddr,
+			      dma_buf->paddr);
+
+		kfree(ioreq);
+	}
+
+	scm->stats.n_free_ioreq = 0;
+
+	return -ENOMEM;
+}
+
+/**
+ * csio_scsim_exit: Uninitialize SCSI Module
+ * @scm: SCSI Module
+ *
+ */
+void
+csio_scsim_exit(struct csio_scsim *scm)
+{
+	struct csio_ioreq *ioreq;
+	struct csio_dma_buf *dma_buf;
+
+	while (!list_empty(&scm->ioreq_freelist)) {
+		struct csio_sm *tmp;
+
+		tmp = list_first_entry(&scm->ioreq_freelist,
+				       struct csio_sm, sm_list);
+		list_del_init(&tmp->sm_list);
+		ioreq = (struct csio_ioreq *)tmp;
+
+		dma_buf = &ioreq->dma_buf;
+		pci_pool_free(scm->hw->scsi_pci_pool, dma_buf->vaddr,
+			      dma_buf->paddr);
+
+		kfree(ioreq);
+	}
+
+	scm->stats.n_free_ioreq = 0;
+
+	csio_scsi_free_ddp_bufs(scm, scm->hw);
+}