/*******************************************************************
 * This file is part of the Emulex Linux Device Driver for         *
 * Fibre Channel Host Bus Adapters.                                *
 * Copyright (C) 2017-2018 Broadcom. All Rights Reserved. The term *
 * “Broadcom” refers to Broadcom Inc. and/or its subsidiaries.  *
 * Copyright (C) 2004-2016 Emulex.  All rights reserved.           *
 * EMULEX and SLI are trademarks of Emulex.                        *
 * www.broadcom.com                                                *
 * Portions Copyright (C) 2004-2005 Christoph Hellwig              *
 *                                                                 *
 * This program is free software; you can redistribute it and/or   *
 * modify it under the terms of version 2 of the GNU General       *
 * Public License as published by the Free Software Foundation.    *
 * This program is distributed in the hope that it will be useful. *
 * ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND          *
 * WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY,  *
 * FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT, ARE      *
 * DISCLAIMED, EXCEPT TO THE EXTENT THAT SUCH DISCLAIMERS ARE HELD *
 * TO BE LEGALLY INVALID.  See the GNU General Public License for  *
 * more details, a copy of which can be found in the file COPYING  *
 * included with this package.                                     *
 *******************************************************************/
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/export.h>
#include <linux/delay.h>
#include <asm/unaligned.h>
#include <linux/t10-pi.h>
#include <linux/crc-t10dif.h>
#include <net/checksum.h>

#include <scsi/scsi.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_tcq.h>
#include <scsi/scsi_transport_fc.h>

#include "lpfc_version.h"
#include "lpfc_hw4.h"
#include "lpfc_hw.h"
#include "lpfc_sli.h"
#include "lpfc_sli4.h"
#include "lpfc_nl.h"
#include "lpfc_disc.h"
#include "lpfc.h"
#include "lpfc_scsi.h"
#include "lpfc_logmsg.h"
#include "lpfc_crtn.h"
#include "lpfc_vport.h"

#define LPFC_RESET_WAIT  2
#define LPFC_ABORT_WAIT  2

int _dump_buf_done = 1;

static char *dif_op_str[] = {
        "PROT_NORMAL",
        "PROT_READ_INSERT",
        "PROT_WRITE_STRIP",
        "PROT_READ_STRIP",
        "PROT_WRITE_INSERT",
        "PROT_READ_PASS",
        "PROT_WRITE_PASS",
};

struct scsi_dif_tuple {
        __be16 guard_tag;       /* Checksum */
        __be16 app_tag;         /* Opaque storage */
        __be32 ref_tag;         /* Target LBA or indirect LBA */
};

static struct lpfc_rport_data *
lpfc_rport_data_from_scsi_device(struct scsi_device *sdev)
{
        struct lpfc_vport *vport = (struct lpfc_vport *)sdev->host->hostdata;

        if (vport->phba->cfg_fof)
                return ((struct lpfc_device_data *)sdev->hostdata)->rport_data;
        else
                return (struct lpfc_rport_data *)sdev->hostdata;
}

static void
lpfc_release_scsi_buf_s4(struct lpfc_hba *phba, struct lpfc_scsi_buf *psb);
static void
lpfc_release_scsi_buf_s3(struct lpfc_hba *phba, struct lpfc_scsi_buf *psb);
static int
lpfc_prot_group_type(struct lpfc_hba *phba, struct scsi_cmnd *sc);

static void
lpfc_debug_save_data(struct lpfc_hba *phba, struct scsi_cmnd *cmnd)
{
        void *src, *dst;
        struct scatterlist *sgde = scsi_sglist(cmnd);

        if (!_dump_buf_data) {
                lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                        "9050 BLKGRD: ERROR %s _dump_buf_data is NULL\n",
                                __func__);
                return;
        }


        if (!sgde) {
                lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                        "9051 BLKGRD: ERROR: data scatterlist is null\n");
                return;
        }

        dst = (void *) _dump_buf_data;
        while (sgde) {
                src = sg_virt(sgde);
                memcpy(dst, src, sgde->length);
                dst += sgde->length;
                sgde = sg_next(sgde);
        }
}

static void
lpfc_debug_save_dif(struct lpfc_hba *phba, struct scsi_cmnd *cmnd)
{
        void *src, *dst;
        struct scatterlist *sgde = scsi_prot_sglist(cmnd);

        if (!_dump_buf_dif) {
                lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                        "9052 BLKGRD: ERROR %s _dump_buf_data is NULL\n",
                                __func__);
                return;
        }

        if (!sgde) {
                lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                        "9053 BLKGRD: ERROR: prot scatterlist is null\n");
                return;
        }

        dst = _dump_buf_dif;
        while (sgde) {
                src = sg_virt(sgde);
                memcpy(dst, src, sgde->length);
                dst += sgde->length;
                sgde = sg_next(sgde);
        }
}

static inline unsigned
lpfc_cmd_blksize(struct scsi_cmnd *sc)
{
        return sc->device->sector_size;
}

#define LPFC_CHECK_PROTECT_GUARD        1
#define LPFC_CHECK_PROTECT_REF          2
static inline unsigned
lpfc_cmd_protect(struct scsi_cmnd *sc, int flag)
{
        return 1;
}

static inline unsigned
lpfc_cmd_guard_csum(struct scsi_cmnd *sc)
{
        if (lpfc_prot_group_type(NULL, sc) == LPFC_PG_TYPE_NO_DIF)
                return 0;
        if (scsi_host_get_guard(sc->device->host) == SHOST_DIX_GUARD_IP)
                return 1;
        return 0;
}

/**
 * lpfc_sli4_set_rsp_sgl_last - Set the last bit in the response sge.
 * @phba: Pointer to HBA object.
 * @lpfc_cmd: lpfc scsi command object pointer.
 *
 * This function is called from the lpfc_prep_task_mgmt_cmd function to
 * set the last bit in the response sge entry.
 **/
static void
lpfc_sli4_set_rsp_sgl_last(struct lpfc_hba *phba,
                                struct lpfc_scsi_buf *lpfc_cmd)
{
        struct sli4_sge *sgl = (struct sli4_sge *)lpfc_cmd->fcp_bpl;
        if (sgl) {
                sgl += 1;
                sgl->word2 = le32_to_cpu(sgl->word2);
                bf_set(lpfc_sli4_sge_last, sgl, 1);
                sgl->word2 = cpu_to_le32(sgl->word2);
        }
}

/**
 * lpfc_update_stats - Update statistical data for the command completion
 * @phba: Pointer to HBA object.
 * @lpfc_cmd: lpfc scsi command object pointer.
 *
 * This function is called when there is a command completion and this
 * function updates the statistical data for the command completion.
 **/
static void
lpfc_update_stats(struct lpfc_hba *phba, struct  lpfc_scsi_buf *lpfc_cmd)
{
        struct lpfc_rport_data *rdata = lpfc_cmd->rdata;
        struct lpfc_nodelist *pnode = rdata->pnode;
        struct scsi_cmnd *cmd = lpfc_cmd->pCmd;
        unsigned long flags;
        struct Scsi_Host  *shost = cmd->device->host;
        struct lpfc_vport *vport = (struct lpfc_vport *) shost->hostdata;
        unsigned long latency;
        int i;

        if (cmd->result)
                return;

        latency = jiffies_to_msecs((long)jiffies - (long)lpfc_cmd->start_time);

        spin_lock_irqsave(shost->host_lock, flags);
        if (!vport->stat_data_enabled ||
                vport->stat_data_blocked ||
                !pnode ||
                !pnode->lat_data ||
                (phba->bucket_type == LPFC_NO_BUCKET)) {
                spin_unlock_irqrestore(shost->host_lock, flags);
                return;
        }

        if (phba->bucket_type == LPFC_LINEAR_BUCKET) {
                i = (latency + phba->bucket_step - 1 - phba->bucket_base)/
                        phba->bucket_step;
                /* check array subscript bounds */
                if (i < 0)
                        i = 0;
                else if (i >= LPFC_MAX_BUCKET_COUNT)
                        i = LPFC_MAX_BUCKET_COUNT - 1;
        } else {
                for (i = 0; i < LPFC_MAX_BUCKET_COUNT-1; i++)
                        if (latency <= (phba->bucket_base +
                                ((1<<i)*phba->bucket_step)))
                                break;
        }

        pnode->lat_data[i].cmd_count++;
        spin_unlock_irqrestore(shost->host_lock, flags);
}

/**
 * lpfc_rampdown_queue_depth - Post RAMP_DOWN_QUEUE event to worker thread
 * @phba: The Hba for which this call is being executed.
 *
 * This routine is called when there is resource error in driver or firmware.
 * This routine posts WORKER_RAMP_DOWN_QUEUE event for @phba. This routine
 * posts at most 1 event each second. This routine wakes up worker thread of
 * @phba to process WORKER_RAM_DOWN_EVENT event.
 *
 * This routine should be called with no lock held.
 **/
void
lpfc_rampdown_queue_depth(struct lpfc_hba *phba)
{
        unsigned long flags;
        uint32_t evt_posted;
        unsigned long expires;

        spin_lock_irqsave(&phba->hbalock, flags);
        atomic_inc(&phba->num_rsrc_err);
        phba->last_rsrc_error_time = jiffies;

        expires = phba->last_ramp_down_time + QUEUE_RAMP_DOWN_INTERVAL;
        if (time_after(expires, jiffies)) {
                spin_unlock_irqrestore(&phba->hbalock, flags);
                return;
        }

        phba->last_ramp_down_time = jiffies;

        spin_unlock_irqrestore(&phba->hbalock, flags);

        spin_lock_irqsave(&phba->pport->work_port_lock, flags);
        evt_posted = phba->pport->work_port_events & WORKER_RAMP_DOWN_QUEUE;
        if (!evt_posted)
                phba->pport->work_port_events |= WORKER_RAMP_DOWN_QUEUE;
        spin_unlock_irqrestore(&phba->pport->work_port_lock, flags);

        if (!evt_posted)
                lpfc_worker_wake_up(phba);
        return;
}

/**
 * lpfc_ramp_down_queue_handler - WORKER_RAMP_DOWN_QUEUE event handler
 * @phba: The Hba for which this call is being executed.
 *
 * This routine is called to  process WORKER_RAMP_DOWN_QUEUE event for worker
 * thread.This routine reduces queue depth for all scsi device on each vport
 * associated with @phba.
 **/
void
lpfc_ramp_down_queue_handler(struct lpfc_hba *phba)
{
        struct lpfc_vport **vports;
        struct Scsi_Host  *shost;
        struct scsi_device *sdev;
        unsigned long new_queue_depth;
        unsigned long num_rsrc_err, num_cmd_success;
        int i;

        num_rsrc_err = atomic_read(&phba->num_rsrc_err);
        num_cmd_success = atomic_read(&phba->num_cmd_success);

        /*
         * The error and success command counters are global per
         * driver instance.  If another handler has already
         * operated on this error event, just exit.
         */
        if (num_rsrc_err == 0)
                return;

        vports = lpfc_create_vport_work_array(phba);
        if (vports != NULL)
                for (i = 0; i <= phba->max_vports && vports[i] != NULL; i++) {
                        shost = lpfc_shost_from_vport(vports[i]);
                        shost_for_each_device(sdev, shost) {
                                new_queue_depth =
                                        sdev->queue_depth * num_rsrc_err /
                                        (num_rsrc_err + num_cmd_success);
                                if (!new_queue_depth)
                                        new_queue_depth = sdev->queue_depth - 1;
                                else
                                        new_queue_depth = sdev->queue_depth -
                                                                new_queue_depth;
                                scsi_change_queue_depth(sdev, new_queue_depth);
                        }
                }
        lpfc_destroy_vport_work_array(phba, vports);
        atomic_set(&phba->num_rsrc_err, 0);
        atomic_set(&phba->num_cmd_success, 0);
}

/**
 * lpfc_scsi_dev_block - set all scsi hosts to block state
 * @phba: Pointer to HBA context object.
 *
 * This function walks vport list and set each SCSI host to block state
 * by invoking fc_remote_port_delete() routine. This function is invoked
 * with EEH when device's PCI slot has been permanently disabled.
 **/
void
lpfc_scsi_dev_block(struct lpfc_hba *phba)
{
        struct lpfc_vport **vports;
        struct Scsi_Host  *shost;
        struct scsi_device *sdev;
        struct fc_rport *rport;
        int i;

        vports = lpfc_create_vport_work_array(phba);
        if (vports != NULL)
                for (i = 0; i <= phba->max_vports && vports[i] != NULL; i++) {
                        shost = lpfc_shost_from_vport(vports[i]);
                        shost_for_each_device(sdev, shost) {
                                rport = starget_to_rport(scsi_target(sdev));
                                fc_remote_port_delete(rport);
                        }
                }
        lpfc_destroy_vport_work_array(phba, vports);
}

/**
 * lpfc_new_scsi_buf_s3 - Scsi buffer allocator for HBA with SLI3 IF spec
 * @vport: The virtual port for which this call being executed.
 * @num_to_allocate: The requested number of buffers to allocate.
 *
 * This routine allocates a scsi buffer for device with SLI-3 interface spec,
 * the scsi buffer contains all the necessary information needed to initiate
 * a SCSI I/O. The non-DMAable buffer region contains information to build
 * the IOCB. The DMAable region contains memory for the FCP CMND, FCP RSP,
 * and the initial BPL. In addition to allocating memory, the FCP CMND and
 * FCP RSP BDEs are setup in the BPL and the BPL BDE is setup in the IOCB.
 *
 * Return codes:
 *   int - number of scsi buffers that were allocated.
 *   0 = failure, less than num_to_alloc is a partial failure.
 **/
static int
lpfc_new_scsi_buf_s3(struct lpfc_vport *vport, int num_to_alloc)
{
        struct lpfc_hba *phba = vport->phba;
        struct lpfc_scsi_buf *psb;
        struct ulp_bde64 *bpl;
        IOCB_t *iocb;
        dma_addr_t pdma_phys_fcp_cmd;
        dma_addr_t pdma_phys_fcp_rsp;
        dma_addr_t pdma_phys_bpl;
        uint16_t iotag;
        int bcnt, bpl_size;

        bpl_size = phba->cfg_sg_dma_buf_size -
                (sizeof(struct fcp_cmnd) + sizeof(struct fcp_rsp));

        lpfc_printf_vlog(vport, KERN_INFO, LOG_FCP,
                         "9067 ALLOC %d scsi_bufs: %d (%d + %d + %d)\n",
                         num_to_alloc, phba->cfg_sg_dma_buf_size,
                         (int)sizeof(struct fcp_cmnd),
                         (int)sizeof(struct fcp_rsp), bpl_size);

        for (bcnt = 0; bcnt < num_to_alloc; bcnt++) {
                psb = kzalloc(sizeof(struct lpfc_scsi_buf), GFP_KERNEL);
                if (!psb)
                        break;

                /*
                 * Get memory from the pci pool to map the virt space to pci
                 * bus space for an I/O.  The DMA buffer includes space for the
                 * struct fcp_cmnd, struct fcp_rsp and the number of bde's
                 * necessary to support the sg_tablesize.
                 */
                psb->data = dma_pool_zalloc(phba->lpfc_sg_dma_buf_pool,
                                        GFP_KERNEL, &psb->dma_handle);
                if (!psb->data) {
                        kfree(psb);
                        break;
                }


                /* Allocate iotag for psb->cur_iocbq. */
                iotag = lpfc_sli_next_iotag(phba, &psb->cur_iocbq);
                if (iotag == 0) {
                        dma_pool_free(phba->lpfc_sg_dma_buf_pool,
                                      psb->data, psb->dma_handle);
                        kfree(psb);
                        break;
                }
                psb->cur_iocbq.iocb_flag |= LPFC_IO_FCP;

                psb->fcp_cmnd = psb->data;
                psb->fcp_rsp = psb->data + sizeof(struct fcp_cmnd);
                psb->fcp_bpl = psb->data + sizeof(struct fcp_cmnd) +
                        sizeof(struct fcp_rsp);

                /* Initialize local short-hand pointers. */
                bpl = psb->fcp_bpl;
                pdma_phys_fcp_cmd = psb->dma_handle;
                pdma_phys_fcp_rsp = psb->dma_handle + sizeof(struct fcp_cmnd);
                pdma_phys_bpl = psb->dma_handle + sizeof(struct fcp_cmnd) +
                        sizeof(struct fcp_rsp);

                /*
                 * The first two bdes are the FCP_CMD and FCP_RSP. The balance
                 * are sg list bdes.  Initialize the first two and leave the
                 * rest for queuecommand.
                 */
                bpl[0].addrHigh = le32_to_cpu(putPaddrHigh(pdma_phys_fcp_cmd));
                bpl[0].addrLow = le32_to_cpu(putPaddrLow(pdma_phys_fcp_cmd));
                bpl[0].tus.f.bdeSize = sizeof(struct fcp_cmnd);
                bpl[0].tus.f.bdeFlags = BUFF_TYPE_BDE_64;
                bpl[0].tus.w = le32_to_cpu(bpl[0].tus.w);

                /* Setup the physical region for the FCP RSP */
                bpl[1].addrHigh = le32_to_cpu(putPaddrHigh(pdma_phys_fcp_rsp));
                bpl[1].addrLow = le32_to_cpu(putPaddrLow(pdma_phys_fcp_rsp));
                bpl[1].tus.f.bdeSize = sizeof(struct fcp_rsp);
                bpl[1].tus.f.bdeFlags = BUFF_TYPE_BDE_64;
                bpl[1].tus.w = le32_to_cpu(bpl[1].tus.w);

                /*
                 * Since the IOCB for the FCP I/O is built into this
                 * lpfc_scsi_buf, initialize it with all known data now.
                 */
                iocb = &psb->cur_iocbq.iocb;
                iocb->un.fcpi64.bdl.ulpIoTag32 = 0;
                if ((phba->sli_rev == 3) &&
                                !(phba->sli3_options & LPFC_SLI3_BG_ENABLED)) {
                        /* fill in immediate fcp command BDE */
                        iocb->un.fcpi64.bdl.bdeFlags = BUFF_TYPE_BDE_IMMED;
                        iocb->un.fcpi64.bdl.bdeSize = sizeof(struct fcp_cmnd);
                        iocb->un.fcpi64.bdl.addrLow = offsetof(IOCB_t,
                                        unsli3.fcp_ext.icd);
                        iocb->un.fcpi64.bdl.addrHigh = 0;
                        iocb->ulpBdeCount = 0;
                        iocb->ulpLe = 0;
                        /* fill in response BDE */
                        iocb->unsli3.fcp_ext.rbde.tus.f.bdeFlags =
                                                        BUFF_TYPE_BDE_64;
                        iocb->unsli3.fcp_ext.rbde.tus.f.bdeSize =
                                sizeof(struct fcp_rsp);
                        iocb->unsli3.fcp_ext.rbde.addrLow =
                                putPaddrLow(pdma_phys_fcp_rsp);
                        iocb->unsli3.fcp_ext.rbde.addrHigh =
                                putPaddrHigh(pdma_phys_fcp_rsp);
                } else {
                        iocb->un.fcpi64.bdl.bdeFlags = BUFF_TYPE_BLP_64;
                        iocb->un.fcpi64.bdl.bdeSize =
                                        (2 * sizeof(struct ulp_bde64));
                        iocb->un.fcpi64.bdl.addrLow =
                                        putPaddrLow(pdma_phys_bpl);
                        iocb->un.fcpi64.bdl.addrHigh =
                                        putPaddrHigh(pdma_phys_bpl);
                        iocb->ulpBdeCount = 1;
                        iocb->ulpLe = 1;
                }
                iocb->ulpClass = CLASS3;
                psb->status = IOSTAT_SUCCESS;
                /* Put it back into the SCSI buffer list */
                psb->cur_iocbq.context1  = psb;
                lpfc_release_scsi_buf_s3(phba, psb);

        }

        return bcnt;
}

/**
 * lpfc_sli4_vport_delete_fcp_xri_aborted -Remove all ndlp references for vport
 * @vport: pointer to lpfc vport data structure.
 *
 * This routine is invoked by the vport cleanup for deletions and the cleanup
 * for an ndlp on removal.
 **/
void
lpfc_sli4_vport_delete_fcp_xri_aborted(struct lpfc_vport *vport)
{
        struct lpfc_hba *phba = vport->phba;
        struct lpfc_scsi_buf *psb, *next_psb;
        unsigned long iflag = 0;

        if (!(phba->cfg_enable_fc4_type & LPFC_ENABLE_FCP))
                return;
        spin_lock_irqsave(&phba->hbalock, iflag);
        spin_lock(&phba->sli4_hba.abts_scsi_buf_list_lock);
        list_for_each_entry_safe(psb, next_psb,
                                &phba->sli4_hba.lpfc_abts_scsi_buf_list, list) {
                if (psb->rdata && psb->rdata->pnode
                        && psb->rdata->pnode->vport == vport)
                        psb->rdata = NULL;
        }
        spin_unlock(&phba->sli4_hba.abts_scsi_buf_list_lock);
        spin_unlock_irqrestore(&phba->hbalock, iflag);
}

/**
 * lpfc_sli4_fcp_xri_aborted - Fast-path process of fcp xri abort
 * @phba: pointer to lpfc hba data structure.
 * @axri: pointer to the fcp xri abort wcqe structure.
 *
 * This routine is invoked by the worker thread to process a SLI4 fast-path
 * FCP aborted xri.
 **/
void
lpfc_sli4_fcp_xri_aborted(struct lpfc_hba *phba,
                          struct sli4_wcqe_xri_aborted *axri)
{
        uint16_t xri = bf_get(lpfc_wcqe_xa_xri, axri);
        uint16_t rxid = bf_get(lpfc_wcqe_xa_remote_xid, axri);
        struct lpfc_scsi_buf *psb, *next_psb;
        unsigned long iflag = 0;
        struct lpfc_iocbq *iocbq;
        int i;
        struct lpfc_nodelist *ndlp;
        int rrq_empty = 0;
        struct lpfc_sli_ring *pring = phba->sli4_hba.els_wq->pring;

        if (!(phba->cfg_enable_fc4_type & LPFC_ENABLE_FCP))
                return;
        spin_lock_irqsave(&phba->hbalock, iflag);
        spin_lock(&phba->sli4_hba.abts_scsi_buf_list_lock);
        list_for_each_entry_safe(psb, next_psb,
                &phba->sli4_hba.lpfc_abts_scsi_buf_list, list) {
                if (psb->cur_iocbq.sli4_xritag == xri) {
                        list_del(&psb->list);
                        psb->exch_busy = 0;
                        psb->status = IOSTAT_SUCCESS;
                        spin_unlock(
                                &phba->sli4_hba.abts_scsi_buf_list_lock);
                        if (psb->rdata && psb->rdata->pnode)
                                ndlp = psb->rdata->pnode;
                        else
                                ndlp = NULL;

                        rrq_empty = list_empty(&phba->active_rrq_list);
                        spin_unlock_irqrestore(&phba->hbalock, iflag);
                        if (ndlp) {
                                lpfc_set_rrq_active(phba, ndlp,
                                        psb->cur_iocbq.sli4_lxritag, rxid, 1);
                                lpfc_sli4_abts_err_handler(phba, ndlp, axri);
                        }
                        lpfc_release_scsi_buf_s4(phba, psb);
                        if (rrq_empty)
                                lpfc_worker_wake_up(phba);
                        return;
                }
        }
        spin_unlock(&phba->sli4_hba.abts_scsi_buf_list_lock);
        for (i = 1; i <= phba->sli.last_iotag; i++) {
                iocbq = phba->sli.iocbq_lookup[i];

                if (!(iocbq->iocb_flag &  LPFC_IO_FCP) ||
                        (iocbq->iocb_flag & LPFC_IO_LIBDFC))
                        continue;
                if (iocbq->sli4_xritag != xri)
                        continue;
                psb = container_of(iocbq, struct lpfc_scsi_buf, cur_iocbq);
                psb->exch_busy = 0;
                spin_unlock_irqrestore(&phba->hbalock, iflag);
                if (!list_empty(&pring->txq))
                        lpfc_worker_wake_up(phba);
                return;

        }
        spin_unlock_irqrestore(&phba->hbalock, iflag);
}

/**
 * lpfc_sli4_post_scsi_sgl_list - Post blocks of scsi buffer sgls from a list
 * @phba: pointer to lpfc hba data structure.
 * @post_sblist: pointer to the scsi buffer list.
 *
 * This routine walks a list of scsi buffers that was passed in. It attempts
 * to construct blocks of scsi buffer sgls which contains contiguous xris and
 * uses the non-embedded SGL block post mailbox commands to post to the port.
 * For single SCSI buffer sgl with non-contiguous xri, if any, it shall use
 * embedded SGL post mailbox command for posting. The @post_sblist passed in
 * must be local list, thus no lock is needed when manipulate the list.
 *
 * Returns: 0 = failure, non-zero number of successfully posted buffers.
 **/
static int
lpfc_sli4_post_scsi_sgl_list(struct lpfc_hba *phba,
                             struct list_head *post_sblist, int sb_count)
{
        struct lpfc_scsi_buf *psb, *psb_next;
        int status, sgl_size;
        int post_cnt = 0, block_cnt = 0, num_posting = 0, num_posted = 0;
        dma_addr_t pdma_phys_bpl1;
        int last_xritag = NO_XRI;
        LIST_HEAD(prep_sblist);
        LIST_HEAD(blck_sblist);
        LIST_HEAD(scsi_sblist);

        /* sanity check */
        if (sb_count <= 0)
                return -EINVAL;

        sgl_size = phba->cfg_sg_dma_buf_size -
                (sizeof(struct fcp_cmnd) + sizeof(struct fcp_rsp));

        list_for_each_entry_safe(psb, psb_next, post_sblist, list) {
                list_del_init(&psb->list);
                block_cnt++;
                if ((last_xritag != NO_XRI) &&
                    (psb->cur_iocbq.sli4_xritag != last_xritag + 1)) {
                        /* a hole in xri block, form a sgl posting block */
                        list_splice_init(&prep_sblist, &blck_sblist);
                        post_cnt = block_cnt - 1;
                        /* prepare list for next posting block */
                        list_add_tail(&psb->list, &prep_sblist);
                        block_cnt = 1;
                } else {
                        /* prepare list for next posting block */
                        list_add_tail(&psb->list, &prep_sblist);
                        /* enough sgls for non-embed sgl mbox command */
                        if (block_cnt == LPFC_NEMBED_MBOX_SGL_CNT) {
                                list_splice_init(&prep_sblist, &blck_sblist);
                                post_cnt = block_cnt;
                                block_cnt = 0;
                        }
                }
                num_posting++;
                last_xritag = psb->cur_iocbq.sli4_xritag;

                /* end of repost sgl list condition for SCSI buffers */
                if (num_posting == sb_count) {
                        if (post_cnt == 0) {
                                /* last sgl posting block */
                                list_splice_init(&prep_sblist, &blck_sblist);
                                post_cnt = block_cnt;
                        } else if (block_cnt == 1) {
                                /* last single sgl with non-contiguous xri */
                                if (sgl_size > SGL_PAGE_SIZE)
                                        pdma_phys_bpl1 = psb->dma_phys_bpl +
                                                                SGL_PAGE_SIZE;
                                else
                                        pdma_phys_bpl1 = 0;
                                status = lpfc_sli4_post_sgl(phba,
                                                psb->dma_phys_bpl,
                                                pdma_phys_bpl1,
                                                psb->cur_iocbq.sli4_xritag);
                                if (status) {
                                        /* failure, put on abort scsi list */
                                        psb->exch_busy = 1;
                                } else {
                                        /* success, put on SCSI buffer list */
                                        psb->exch_busy = 0;
                                        psb->status = IOSTAT_SUCCESS;
                                        num_posted++;
                                }
                                /* success, put on SCSI buffer sgl list */
                                list_add_tail(&psb->list, &scsi_sblist);
                        }
                }

                /* continue until a nembed page worth of sgls */
                if (post_cnt == 0)
                        continue;

                /* post block of SCSI buffer list sgls */
                status = lpfc_sli4_post_scsi_sgl_block(phba, &blck_sblist,
                                                       post_cnt);

                /* don't reset xirtag due to hole in xri block */
                if (block_cnt == 0)
                        last_xritag = NO_XRI;

                /* reset SCSI buffer post count for next round of posting */
                post_cnt = 0;

                /* put posted SCSI buffer-sgl posted on SCSI buffer sgl list */
                while (!list_empty(&blck_sblist)) {
                        list_remove_head(&blck_sblist, psb,
                                         struct lpfc_scsi_buf, list);
                        if (status) {
                                /* failure, put on abort scsi list */
                                psb->exch_busy = 1;
                        } else {
                                /* success, put on SCSI buffer list */
                                psb->exch_busy = 0;
                                psb->status = IOSTAT_SUCCESS;
                                num_posted++;
                        }
                        list_add_tail(&psb->list, &scsi_sblist);
                }
        }
        /* Push SCSI buffers with sgl posted to the availble list */
        while (!list_empty(&scsi_sblist)) {
                list_remove_head(&scsi_sblist, psb,
                                 struct lpfc_scsi_buf, list);
                lpfc_release_scsi_buf_s4(phba, psb);
        }
        return num_posted;
}

/**
 * lpfc_sli4_repost_scsi_sgl_list - Repost all the allocated scsi buffer sgls
 * @phba: pointer to lpfc hba data structure.
 *
 * This routine walks the list of scsi buffers that have been allocated and
 * repost them to the port by using SGL block post. This is needed after a
 * pci_function_reset/warm_start or start. The lpfc_hba_down_post_s4 routine
 * is responsible for moving all scsi buffers on the lpfc_abts_scsi_sgl_list
 * to the lpfc_scsi_buf_list. If the repost fails, reject all scsi buffers.
 *
 * Returns: 0 = success, non-zero failure.
 **/
int
lpfc_sli4_repost_scsi_sgl_list(struct lpfc_hba *phba)
{
        LIST_HEAD(post_sblist);
        int num_posted, rc = 0;

        /* get all SCSI buffers need to repost to a local list */
        spin_lock_irq(&phba->scsi_buf_list_get_lock);
        spin_lock(&phba->scsi_buf_list_put_lock);
        list_splice_init(&phba->lpfc_scsi_buf_list_get, &post_sblist);
        list_splice(&phba->lpfc_scsi_buf_list_put, &post_sblist);
        spin_unlock(&phba->scsi_buf_list_put_lock);
        spin_unlock_irq(&phba->scsi_buf_list_get_lock);

        /* post the list of scsi buffer sgls to port if available */
        if (!list_empty(&post_sblist)) {
                num_posted = lpfc_sli4_post_scsi_sgl_list(phba, &post_sblist,
                                                phba->sli4_hba.scsi_xri_cnt);
                /* failed to post any scsi buffer, return error */
                if (num_posted == 0)
                        rc = -EIO;
        }
        return rc;
}

/**
 * lpfc_new_scsi_buf_s4 - Scsi buffer allocator for HBA with SLI4 IF spec
 * @vport: The virtual port for which this call being executed.
 * @num_to_allocate: The requested number of buffers to allocate.
 *
 * This routine allocates scsi buffers for device with SLI-4 interface spec,
 * the scsi buffer contains all the necessary information needed to initiate
 * a SCSI I/O. After allocating up to @num_to_allocate SCSI buffers and put
 * them on a list, it post them to the port by using SGL block post.
 *
 * Return codes:
 *   int - number of scsi buffers that were allocated and posted.
 *   0 = failure, less than num_to_alloc is a partial failure.
 **/
static int
lpfc_new_scsi_buf_s4(struct lpfc_vport *vport, int num_to_alloc)
{
        struct lpfc_hba *phba = vport->phba;
        struct lpfc_scsi_buf *psb;
        struct sli4_sge *sgl;
        IOCB_t *iocb;
        dma_addr_t pdma_phys_fcp_cmd;
        dma_addr_t pdma_phys_fcp_rsp;
        dma_addr_t pdma_phys_bpl;
        uint16_t iotag, lxri = 0;
        int bcnt, num_posted, sgl_size;
        LIST_HEAD(prep_sblist);
        LIST_HEAD(post_sblist);
        LIST_HEAD(scsi_sblist);

        sgl_size = phba->cfg_sg_dma_buf_size -
                (sizeof(struct fcp_cmnd) + sizeof(struct fcp_rsp));

        lpfc_printf_vlog(vport, KERN_INFO, LOG_FCP,
                         "9068 ALLOC %d scsi_bufs: %d (%d + %d + %d)\n",
                         num_to_alloc, phba->cfg_sg_dma_buf_size, sgl_size,
                         (int)sizeof(struct fcp_cmnd),
                         (int)sizeof(struct fcp_rsp));

        for (bcnt = 0; bcnt < num_to_alloc; bcnt++) {
                psb = kzalloc(sizeof(struct lpfc_scsi_buf), GFP_KERNEL);
                if (!psb)
                        break;
                /*
                 * Get memory from the pci pool to map the virt space to
                 * pci bus space for an I/O. The DMA buffer includes space
                 * for the struct fcp_cmnd, struct fcp_rsp and the number
                 * of bde's necessary to support the sg_tablesize.
                 */
                psb->data = dma_pool_zalloc(phba->lpfc_sg_dma_buf_pool,
                                                GFP_KERNEL, &psb->dma_handle);
                if (!psb->data) {
                        kfree(psb);
                        break;
                }

                /*
                 * 4K Page alignment is CRITICAL to BlockGuard, double check
                 * to be sure.
                 */
                if ((phba->sli3_options & LPFC_SLI3_BG_ENABLED) &&
                    (((unsigned long)(psb->data) &
                    (unsigned long)(SLI4_PAGE_SIZE - 1)) != 0)) {
                        lpfc_printf_log(phba, KERN_ERR, LOG_FCP,
                                        "3369 Memory alignment error "
                                        "addr=%lx\n",
                                        (unsigned long)psb->data);
                        dma_pool_free(phba->lpfc_sg_dma_buf_pool,
                                      psb->data, psb->dma_handle);
                        kfree(psb);
                        break;
                }


                lxri = lpfc_sli4_next_xritag(phba);
                if (lxri == NO_XRI) {
                        dma_pool_free(phba->lpfc_sg_dma_buf_pool,
                                      psb->data, psb->dma_handle);
                        kfree(psb);
                        break;
                }

                /* Allocate iotag for psb->cur_iocbq. */
                iotag = lpfc_sli_next_iotag(phba, &psb->cur_iocbq);
                if (iotag == 0) {
                        dma_pool_free(phba->lpfc_sg_dma_buf_pool,
                                      psb->data, psb->dma_handle);
                        kfree(psb);
                        lpfc_printf_log(phba, KERN_ERR, LOG_FCP,
                                        "3368 Failed to allocate IOTAG for"
                                        " XRI:0x%x\n", lxri);
                        lpfc_sli4_free_xri(phba, lxri);
                        break;
                }
                psb->cur_iocbq.sli4_lxritag = lxri;
                psb->cur_iocbq.sli4_xritag = phba->sli4_hba.xri_ids[lxri];
                psb->cur_iocbq.iocb_flag |= LPFC_IO_FCP;
                psb->fcp_bpl = psb->data;
                psb->fcp_cmnd = (psb->data + sgl_size);
                psb->fcp_rsp = (struct fcp_rsp *)((uint8_t *)psb->fcp_cmnd +
                                        sizeof(struct fcp_cmnd));

                /* Initialize local short-hand pointers. */
                sgl = (struct sli4_sge *)psb->fcp_bpl;
                pdma_phys_bpl = psb->dma_handle;
                pdma_phys_fcp_cmd = (psb->dma_handle + sgl_size);
                pdma_phys_fcp_rsp = pdma_phys_fcp_cmd + sizeof(struct fcp_cmnd);

                /*
                 * The first two bdes are the FCP_CMD and FCP_RSP.
                 * The balance are sg list bdes. Initialize the
                 * first two and leave the rest for queuecommand.
                 */
                sgl->addr_hi = cpu_to_le32(putPaddrHigh(pdma_phys_fcp_cmd));
                sgl->addr_lo = cpu_to_le32(putPaddrLow(pdma_phys_fcp_cmd));
                sgl->word2 = le32_to_cpu(sgl->word2);
                bf_set(lpfc_sli4_sge_last, sgl, 0);
                sgl->word2 = cpu_to_le32(sgl->word2);
                sgl->sge_len = cpu_to_le32(sizeof(struct fcp_cmnd));
                sgl++;

                /* Setup the physical region for the FCP RSP */
                sgl->addr_hi = cpu_to_le32(putPaddrHigh(pdma_phys_fcp_rsp));
                sgl->addr_lo = cpu_to_le32(putPaddrLow(pdma_phys_fcp_rsp));
                sgl->word2 = le32_to_cpu(sgl->word2);
                bf_set(lpfc_sli4_sge_last, sgl, 1);
                sgl->word2 = cpu_to_le32(sgl->word2);
                sgl->sge_len = cpu_to_le32(sizeof(struct fcp_rsp));

                /*
                 * Since the IOCB for the FCP I/O is built into this
                 * lpfc_scsi_buf, initialize it with all known data now.
                 */
                iocb = &psb->cur_iocbq.iocb;
                iocb->un.fcpi64.bdl.ulpIoTag32 = 0;
                iocb->un.fcpi64.bdl.bdeFlags = BUFF_TYPE_BDE_64;
                /* setting the BLP size to 2 * sizeof BDE may not be correct.
                 * We are setting the bpl to point to out sgl. An sgl's
                 * entries are 16 bytes, a bpl entries are 12 bytes.
                 */
                iocb->un.fcpi64.bdl.bdeSize = sizeof(struct fcp_cmnd);
                iocb->un.fcpi64.bdl.addrLow = putPaddrLow(pdma_phys_fcp_cmd);
                iocb->un.fcpi64.bdl.addrHigh = putPaddrHigh(pdma_phys_fcp_cmd);
                iocb->ulpBdeCount = 1;
                iocb->ulpLe = 1;
                iocb->ulpClass = CLASS3;
                psb->cur_iocbq.context1 = psb;
                psb->dma_phys_bpl = pdma_phys_bpl;

                /* add the scsi buffer to a post list */
                list_add_tail(&psb->list, &post_sblist);
                spin_lock_irq(&phba->scsi_buf_list_get_lock);
                phba->sli4_hba.scsi_xri_cnt++;
                spin_unlock_irq(&phba->scsi_buf_list_get_lock);
        }
        lpfc_printf_log(phba, KERN_INFO, LOG_BG | LOG_FCP,
                        "3021 Allocate %d out of %d requested new SCSI "
                        "buffers\n", bcnt, num_to_alloc);

        /* post the list of scsi buffer sgls to port if available */
        if (!list_empty(&post_sblist))
                num_posted = lpfc_sli4_post_scsi_sgl_list(phba,
                                                          &post_sblist, bcnt);
        else
                num_posted = 0;

        return num_posted;
}

/**
 * lpfc_new_scsi_buf - Wrapper funciton for scsi buffer allocator
 * @vport: The virtual port for which this call being executed.
 * @num_to_allocate: The requested number of buffers to allocate.
 *
 * This routine wraps the actual SCSI buffer allocator function pointer from
 * the lpfc_hba struct.
 *
 * Return codes:
 *   int - number of scsi buffers that were allocated.
 *   0 = failure, less than num_to_alloc is a partial failure.
 **/
static inline int
lpfc_new_scsi_buf(struct lpfc_vport *vport, int num_to_alloc)
{
        return vport->phba->lpfc_new_scsi_buf(vport, num_to_alloc);
}

/**
 * lpfc_get_scsi_buf_s3 - Get a scsi buffer from lpfc_scsi_buf_list of the HBA
 * @phba: The HBA for which this call is being executed.
 *
 * This routine removes a scsi buffer from head of @phba lpfc_scsi_buf_list list
 * and returns to caller.
 *
 * Return codes:
 *   NULL - Error
 *   Pointer to lpfc_scsi_buf - Success
 **/
static struct lpfc_scsi_buf*
lpfc_get_scsi_buf_s3(struct lpfc_hba *phba, struct lpfc_nodelist *ndlp)
{
        struct  lpfc_scsi_buf * lpfc_cmd = NULL;
        struct list_head *scsi_buf_list_get = &phba->lpfc_scsi_buf_list_get;
        unsigned long iflag = 0;

        spin_lock_irqsave(&phba->scsi_buf_list_get_lock, iflag);
        list_remove_head(scsi_buf_list_get, lpfc_cmd, struct lpfc_scsi_buf,
                         list);
        if (!lpfc_cmd) {
                spin_lock(&phba->scsi_buf_list_put_lock);
                list_splice(&phba->lpfc_scsi_buf_list_put,
                            &phba->lpfc_scsi_buf_list_get);
                INIT_LIST_HEAD(&phba->lpfc_scsi_buf_list_put);
                list_remove_head(scsi_buf_list_get, lpfc_cmd,
                                 struct lpfc_scsi_buf, list);
                spin_unlock(&phba->scsi_buf_list_put_lock);
        }
        spin_unlock_irqrestore(&phba->scsi_buf_list_get_lock, iflag);

        if (lpfc_ndlp_check_qdepth(phba, ndlp) && lpfc_cmd) {
                atomic_inc(&ndlp->cmd_pending);

                lpfc_cmd->flags |= LPFC_SBUF_BUMP_QDEPTH;
        }
        return  lpfc_cmd;
}
/**
 * lpfc_get_scsi_buf_s4 - Get a scsi buffer from lpfc_scsi_buf_list of the HBA
 * @phba: The HBA for which this call is being executed.
 *
 * This routine removes a scsi buffer from head of @phba lpfc_scsi_buf_list list
 * and returns to caller.
 *
 * Return codes:
 *   NULL - Error
 *   Pointer to lpfc_scsi_buf - Success
 **/
static struct lpfc_scsi_buf*
lpfc_get_scsi_buf_s4(struct lpfc_hba *phba, struct lpfc_nodelist *ndlp)
{
        struct lpfc_scsi_buf *lpfc_cmd, *lpfc_cmd_next;
        unsigned long iflag = 0;
        int found = 0;

        spin_lock_irqsave(&phba->scsi_buf_list_get_lock, iflag);
        list_for_each_entry_safe(lpfc_cmd, lpfc_cmd_next,
                                 &phba->lpfc_scsi_buf_list_get, list) {
                if (lpfc_test_rrq_active(phba, ndlp,
                                         lpfc_cmd->cur_iocbq.sli4_lxritag))
                        continue;
                list_del_init(&lpfc_cmd->list);
                found = 1;
                break;
        }
        if (!found) {
                spin_lock(&phba->scsi_buf_list_put_lock);
                list_splice(&phba->lpfc_scsi_buf_list_put,
                            &phba->lpfc_scsi_buf_list_get);
                INIT_LIST_HEAD(&phba->lpfc_scsi_buf_list_put);
                spin_unlock(&phba->scsi_buf_list_put_lock);
                list_for_each_entry_safe(lpfc_cmd, lpfc_cmd_next,
                                         &phba->lpfc_scsi_buf_list_get, list) {
                        if (lpfc_test_rrq_active(
                                phba, ndlp, lpfc_cmd->cur_iocbq.sli4_lxritag))
                                continue;
                        list_del_init(&lpfc_cmd->list);
                        found = 1;
                        break;
                }
        }
        spin_unlock_irqrestore(&phba->scsi_buf_list_get_lock, iflag);
        if (!found)
                return NULL;

        if (lpfc_ndlp_check_qdepth(phba, ndlp) && lpfc_cmd) {
                atomic_inc(&ndlp->cmd_pending);
                lpfc_cmd->flags |= LPFC_SBUF_BUMP_QDEPTH;
        }
        return  lpfc_cmd;
}
/**
 * lpfc_get_scsi_buf - Get a scsi buffer from lpfc_scsi_buf_list of the HBA
 * @phba: The HBA for which this call is being executed.
 *
 * This routine removes a scsi buffer from head of @phba lpfc_scsi_buf_list list
 * and returns to caller.
 *
 * Return codes:
 *   NULL - Error
 *   Pointer to lpfc_scsi_buf - Success
 **/
static struct lpfc_scsi_buf*
lpfc_get_scsi_buf(struct lpfc_hba *phba, struct lpfc_nodelist *ndlp)
{
        return  phba->lpfc_get_scsi_buf(phba, ndlp);
}

/**
 * lpfc_release_scsi_buf - Return a scsi buffer back to hba scsi buf list
 * @phba: The Hba for which this call is being executed.
 * @psb: The scsi buffer which is being released.
 *
 * This routine releases @psb scsi buffer by adding it to tail of @phba
 * lpfc_scsi_buf_list list.
 **/
static void
lpfc_release_scsi_buf_s3(struct lpfc_hba *phba, struct lpfc_scsi_buf *psb)
{
        unsigned long iflag = 0;

        psb->seg_cnt = 0;
        psb->nonsg_phys = 0;
        psb->prot_seg_cnt = 0;

        spin_lock_irqsave(&phba->scsi_buf_list_put_lock, iflag);
        psb->pCmd = NULL;
        psb->cur_iocbq.iocb_flag = LPFC_IO_FCP;
        list_add_tail(&psb->list, &phba->lpfc_scsi_buf_list_put);
        spin_unlock_irqrestore(&phba->scsi_buf_list_put_lock, iflag);
}

/**
 * lpfc_release_scsi_buf_s4: Return a scsi buffer back to hba scsi buf list.
 * @phba: The Hba for which this call is being executed.
 * @psb: The scsi buffer which is being released.
 *
 * This routine releases @psb scsi buffer by adding it to tail of @phba
 * lpfc_scsi_buf_list list. For SLI4 XRI's are tied to the scsi buffer
 * and cannot be reused for at least RA_TOV amount of time if it was
 * aborted.
 **/
static void
lpfc_release_scsi_buf_s4(struct lpfc_hba *phba, struct lpfc_scsi_buf *psb)
{
        unsigned long iflag = 0;

        psb->seg_cnt = 0;
        psb->nonsg_phys = 0;
        psb->prot_seg_cnt = 0;

        if (psb->exch_busy) {
                spin_lock_irqsave(&phba->sli4_hba.abts_scsi_buf_list_lock,
                                        iflag);
                psb->pCmd = NULL;
                list_add_tail(&psb->list,
                        &phba->sli4_hba.lpfc_abts_scsi_buf_list);
                spin_unlock_irqrestore(&phba->sli4_hba.abts_scsi_buf_list_lock,
                                        iflag);
        } else {
                psb->pCmd = NULL;
                psb->cur_iocbq.iocb_flag = LPFC_IO_FCP;
                spin_lock_irqsave(&phba->scsi_buf_list_put_lock, iflag);
                list_add_tail(&psb->list, &phba->lpfc_scsi_buf_list_put);
                spin_unlock_irqrestore(&phba->scsi_buf_list_put_lock, iflag);
        }
}

/**
 * lpfc_release_scsi_buf: Return a scsi buffer back to hba scsi buf list.
 * @phba: The Hba for which this call is being executed.
 * @psb: The scsi buffer which is being released.
 *
 * This routine releases @psb scsi buffer by adding it to tail of @phba
 * lpfc_scsi_buf_list list.
 **/
static void
lpfc_release_scsi_buf(struct lpfc_hba *phba, struct lpfc_scsi_buf *psb)
{
        if ((psb->flags & LPFC_SBUF_BUMP_QDEPTH) && psb->ndlp)
                atomic_dec(&psb->ndlp->cmd_pending);

        psb->flags &= ~LPFC_SBUF_BUMP_QDEPTH;
        phba->lpfc_release_scsi_buf(phba, psb);
}

/**
 * lpfc_scsi_prep_dma_buf_s3 - DMA mapping for scsi buffer to SLI3 IF spec
 * @phba: The Hba for which this call is being executed.
 * @lpfc_cmd: The scsi buffer which is going to be mapped.
 *
 * This routine does the pci dma mapping for scatter-gather list of scsi cmnd
 * field of @lpfc_cmd for device with SLI-3 interface spec. This routine scans
 * through sg elements and format the bde. This routine also initializes all
 * IOCB fields which are dependent on scsi command request buffer.
 *
 * Return codes:
 *   1 - Error
 *   0 - Success
 **/
static int
lpfc_scsi_prep_dma_buf_s3(struct lpfc_hba *phba, struct lpfc_scsi_buf *lpfc_cmd)
{
        struct scsi_cmnd *scsi_cmnd = lpfc_cmd->pCmd;
        struct scatterlist *sgel = NULL;
        struct fcp_cmnd *fcp_cmnd = lpfc_cmd->fcp_cmnd;
        struct ulp_bde64 *bpl = lpfc_cmd->fcp_bpl;
        struct lpfc_iocbq *iocbq = &lpfc_cmd->cur_iocbq;
        IOCB_t *iocb_cmd = &lpfc_cmd->cur_iocbq.iocb;
        struct ulp_bde64 *data_bde = iocb_cmd->unsli3.fcp_ext.dbde;
        dma_addr_t physaddr;
        uint32_t num_bde = 0;
        int nseg, datadir = scsi_cmnd->sc_data_direction;

        /*
         * There are three possibilities here - use scatter-gather segment, use
         * the single mapping, or neither.  Start the lpfc command prep by
         * bumping the bpl beyond the fcp_cmnd and fcp_rsp regions to the first
         * data bde entry.
         */
        bpl += 2;
        if (scsi_sg_count(scsi_cmnd)) {
                /*
                 * The driver stores the segment count returned from pci_map_sg
                 * because this a count of dma-mappings used to map the use_sg
                 * pages.  They are not guaranteed to be the same for those
                 * architectures that implement an IOMMU.
                 */

                nseg = dma_map_sg(&phba->pcidev->dev, scsi_sglist(scsi_cmnd),
                                  scsi_sg_count(scsi_cmnd), datadir);
                if (unlikely(!nseg))
                        return 1;

                lpfc_cmd->seg_cnt = nseg;
                if (lpfc_cmd->seg_cnt > phba->cfg_sg_seg_cnt) {
                        lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                                "9064 BLKGRD: %s: Too many sg segments from "
                               "dma_map_sg.  Config %d, seg_cnt %d\n",
                               __func__, phba->cfg_sg_seg_cnt,
                               lpfc_cmd->seg_cnt);
                        lpfc_cmd->seg_cnt = 0;
                        scsi_dma_unmap(scsi_cmnd);
                        return 1;
                }

                /*
                 * The driver established a maximum scatter-gather segment count
                 * during probe that limits the number of sg elements in any
                 * single scsi command.  Just run through the seg_cnt and format
                 * the bde's.
                 * When using SLI-3 the driver will try to fit all the BDEs into
                 * the IOCB. If it can't then the BDEs get added to a BPL as it
                 * does for SLI-2 mode.
                 */
                scsi_for_each_sg(scsi_cmnd, sgel, nseg, num_bde) {
                        physaddr = sg_dma_address(sgel);
                        if (phba->sli_rev == 3 &&
                            !(phba->sli3_options & LPFC_SLI3_BG_ENABLED) &&
                            !(iocbq->iocb_flag & DSS_SECURITY_OP) &&
                            nseg <= LPFC_EXT_DATA_BDE_COUNT) {
                                data_bde->tus.f.bdeFlags = BUFF_TYPE_BDE_64;
                                data_bde->tus.f.bdeSize = sg_dma_len(sgel);
                                data_bde->addrLow = putPaddrLow(physaddr);
                                data_bde->addrHigh = putPaddrHigh(physaddr);
                                data_bde++;
                        } else {
                                bpl->tus.f.bdeFlags = BUFF_TYPE_BDE_64;
                                bpl->tus.f.bdeSize = sg_dma_len(sgel);
                                bpl->tus.w = le32_to_cpu(bpl->tus.w);
                                bpl->addrLow =
                                        le32_to_cpu(putPaddrLow(physaddr));
                                bpl->addrHigh =
                                        le32_to_cpu(putPaddrHigh(physaddr));
                                bpl++;
                        }
                }
        }

        /*
         * Finish initializing those IOCB fields that are dependent on the
         * scsi_cmnd request_buffer.  Note that for SLI-2 the bdeSize is
         * explicitly reinitialized and for SLI-3 the extended bde count is
         * explicitly reinitialized since all iocb memory resources are reused.
         */
        if (phba->sli_rev == 3 &&
            !(phba->sli3_options & LPFC_SLI3_BG_ENABLED) &&
            !(iocbq->iocb_flag & DSS_SECURITY_OP)) {
                if (num_bde > LPFC_EXT_DATA_BDE_COUNT) {
                        /*
                         * The extended IOCB format can only fit 3 BDE or a BPL.
                         * This I/O has more than 3 BDE so the 1st data bde will
                         * be a BPL that is filled in here.
                         */
                        physaddr = lpfc_cmd->dma_handle;
                        data_bde->tus.f.bdeFlags = BUFF_TYPE_BLP_64;
                        data_bde->tus.f.bdeSize = (num_bde *
                                                   sizeof(struct ulp_bde64));
                        physaddr += (sizeof(struct fcp_cmnd) +
                                     sizeof(struct fcp_rsp) +
                                     (2 * sizeof(struct ulp_bde64)));
                        data_bde->addrHigh = putPaddrHigh(physaddr);
                        data_bde->addrLow = putPaddrLow(physaddr);
                        /* ebde count includes the response bde and data bpl */
                        iocb_cmd->unsli3.fcp_ext.ebde_count = 2;
                } else {
                        /* ebde count includes the response bde and data bdes */
                        iocb_cmd->unsli3.fcp_ext.ebde_count = (num_bde + 1);
                }
        } else {
                iocb_cmd->un.fcpi64.bdl.bdeSize =
                        ((num_bde + 2) * sizeof(struct ulp_bde64));
                iocb_cmd->unsli3.fcp_ext.ebde_count = (num_bde + 1);
        }
        fcp_cmnd->fcpDl = cpu_to_be32(scsi_bufflen(scsi_cmnd));

        /*
         * Due to difference in data length between DIF/non-DIF paths,
         * we need to set word 4 of IOCB here
         */
        iocb_cmd->un.fcpi.fcpi_parm = scsi_bufflen(scsi_cmnd);
        return 0;
}

#ifdef CONFIG_SCSI_LPFC_DEBUG_FS

/* Return BG_ERR_INIT if error injection is detected by Initiator */
#define BG_ERR_INIT     0x1
/* Return BG_ERR_TGT if error injection is detected by Target */
#define BG_ERR_TGT      0x2
/* Return BG_ERR_SWAP if swapping CSUM<-->CRC is required for error injection */
#define BG_ERR_SWAP     0x10
/**
 * Return BG_ERR_CHECK if disabling Guard/Ref/App checking is required for
 * error injection
 **/
#define BG_ERR_CHECK    0x20

/**
 * lpfc_bg_err_inject - Determine if we should inject an error
 * @phba: The Hba for which this call is being executed.
 * @sc: The SCSI command to examine
 * @reftag: (out) BlockGuard reference tag for transmitted data
 * @apptag: (out) BlockGuard application tag for transmitted data
 * @new_guard (in) Value to replace CRC with if needed
 *
 * Returns BG_ERR_* bit mask or 0 if request ignored
 **/
static int
lpfc_bg_err_inject(struct lpfc_hba *phba, struct scsi_cmnd *sc,
                uint32_t *reftag, uint16_t *apptag, uint32_t new_guard)
{
        struct scatterlist *sgpe; /* s/g prot entry */
        struct lpfc_scsi_buf *lpfc_cmd = NULL;
        struct scsi_dif_tuple *src = NULL;
        struct lpfc_nodelist *ndlp;
        struct lpfc_rport_data *rdata;
        uint32_t op = scsi_get_prot_op(sc);
        uint32_t blksize;
        uint32_t numblks;
        sector_t lba;
        int rc = 0;
        int blockoff = 0;

        if (op == SCSI_PROT_NORMAL)
                return 0;

        sgpe = scsi_prot_sglist(sc);
        lba = scsi_get_lba(sc);

        /* First check if we need to match the LBA */
        if (phba->lpfc_injerr_lba != LPFC_INJERR_LBA_OFF) {
                blksize = lpfc_cmd_blksize(sc);
                numblks = (scsi_bufflen(sc) + blksize - 1) / blksize;

                /* Make sure we have the right LBA if one is specified */
                if ((phba->lpfc_injerr_lba < lba) ||
                        (phba->lpfc_injerr_lba >= (lba + numblks)))
                        return 0;
                if (sgpe) {
                        blockoff = phba->lpfc_injerr_lba - lba;
                        numblks = sg_dma_len(sgpe) /
                                sizeof(struct scsi_dif_tuple);
                        if (numblks < blockoff)
                                blockoff = numblks;
                }
        }

        /* Next check if we need to match the remote NPortID or WWPN */
        rdata = lpfc_rport_data_from_scsi_device(sc->device);
        if (rdata && rdata->pnode) {
                ndlp = rdata->pnode;

                /* Make sure we have the right NPortID if one is specified */
                if (phba->lpfc_injerr_nportid  &&
                        (phba->lpfc_injerr_nportid != ndlp->nlp_DID))
                        return 0;

                /*
                 * Make sure we have the right WWPN if one is specified.
                 * wwn[0] should be a non-zero NAA in a good WWPN.
                 */
                if (phba->lpfc_injerr_wwpn.u.wwn[0]  &&
                        (memcmp(&ndlp->nlp_portname, &phba->lpfc_injerr_wwpn,
                                sizeof(struct lpfc_name)) != 0))
                        return 0;
        }

        /* Setup a ptr to the protection data if the SCSI host provides it */
        if (sgpe) {
                src = (struct scsi_dif_tuple *)sg_virt(sgpe);
                src += blockoff;
                lpfc_cmd = (struct lpfc_scsi_buf *)sc->host_scribble;
        }

        /* Should we change the Reference Tag */
        if (reftag) {
                if (phba->lpfc_injerr_wref_cnt) {
                        switch (op) {
                        case SCSI_PROT_WRITE_PASS:
                                if (src) {
                                        /*
                                         * For WRITE_PASS, force the error
                                         * to be sent on the wire. It should
                                         * be detected by the Target.
                                         * If blockoff != 0 error will be
                                         * inserted in middle of the IO.
                                         */

                                        lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                                        "9076 BLKGRD: Injecting reftag error: "
                                        "write lba x%lx + x%x oldrefTag x%x\n",
                                        (unsigned long)lba, blockoff,
                                        be32_to_cpu(src->ref_tag));

                                        /*
                                         * Save the old ref_tag so we can
                                         * restore it on completion.
                                         */
                                        if (lpfc_cmd) {
                                                lpfc_cmd->prot_data_type =
                                                        LPFC_INJERR_REFTAG;
                                                lpfc_cmd->prot_data_segment =
                                                        src;
                                                lpfc_cmd->prot_data =
                                                        src->ref_tag;
                                        }
                                        src->ref_tag = cpu_to_be32(0xDEADBEEF);
                                        phba->lpfc_injerr_wref_cnt--;
                                        if (phba->lpfc_injerr_wref_cnt == 0) {
                                                phba->lpfc_injerr_nportid = 0;
                                                phba->lpfc_injerr_lba =
                                                        LPFC_INJERR_LBA_OFF;
                                                memset(&phba->lpfc_injerr_wwpn,
                                                  0, sizeof(struct lpfc_name));
                                        }
                                        rc = BG_ERR_TGT | BG_ERR_CHECK;

                                        break;
                                }
                                /* Drop thru */
                        case SCSI_PROT_WRITE_INSERT:
                                /*
                                 * For WRITE_INSERT, force the error
                                 * to be sent on the wire. It should be
                                 * detected by the Target.
                                 */
                                /* DEADBEEF will be the reftag on the wire */
                                *reftag = 0xDEADBEEF;
                                phba->lpfc_injerr_wref_cnt--;
                                if (phba->lpfc_injerr_wref_cnt == 0) {
                                        phba->lpfc_injerr_nportid = 0;
                                        phba->lpfc_injerr_lba =
                                        LPFC_INJERR_LBA_OFF;
                                        memset(&phba->lpfc_injerr_wwpn,
                                                0, sizeof(struct lpfc_name));
                                }
                                rc = BG_ERR_TGT | BG_ERR_CHECK;

                                lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                                        "9078 BLKGRD: Injecting reftag error: "
                                        "write lba x%lx\n", (unsigned long)lba);
                                break;
                        case SCSI_PROT_WRITE_STRIP:
                                /*
                                 * For WRITE_STRIP and WRITE_PASS,
                                 * force the error on data
                                 * being copied from SLI-Host to SLI-Port.
                                 */
                                *reftag = 0xDEADBEEF;
                                phba->lpfc_injerr_wref_cnt--;
                                if (phba->lpfc_injerr_wref_cnt == 0) {
                                        phba->lpfc_injerr_nportid = 0;
                                        phba->lpfc_injerr_lba =
                                                LPFC_INJERR_LBA_OFF;
                                        memset(&phba->lpfc_injerr_wwpn,
                                                0, sizeof(struct lpfc_name));
                                }
                                rc = BG_ERR_INIT;

                                lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                                        "9077 BLKGRD: Injecting reftag error: "
                                        "write lba x%lx\n", (unsigned long)lba);
                                break;
                        }
                }
                if (phba->lpfc_injerr_rref_cnt) {
                        switch (op) {
                        case SCSI_PROT_READ_INSERT:
                        case SCSI_PROT_READ_STRIP:
                        case SCSI_PROT_READ_PASS:
                                /*
                                 * For READ_STRIP and READ_PASS, force the
                                 * error on data being read off the wire. It
                                 * should force an IO error to the driver.
                                 */
                                *reftag = 0xDEADBEEF;
                                phba->lpfc_injerr_rref_cnt--;
                                if (phba->lpfc_injerr_rref_cnt == 0) {
                                        phba->lpfc_injerr_nportid = 0;
                                        phba->lpfc_injerr_lba =
                                                LPFC_INJERR_LBA_OFF;
                                        memset(&phba->lpfc_injerr_wwpn,
                                                0, sizeof(struct lpfc_name));
                                }
                                rc = BG_ERR_INIT;

                                lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                                        "9079 BLKGRD: Injecting reftag error: "
                                        "read lba x%lx\n", (unsigned long)lba);
                                break;
                        }
                }
        }

        /* Should we change the Application Tag */
        if (apptag) {
                if (phba->lpfc_injerr_wapp_cnt) {
                        switch (op) {
                        case SCSI_PROT_WRITE_PASS:
                                if (src) {
                                        /*
                                         * For WRITE_PASS, force the error
                                         * to be sent on the wire. It should
                                         * be detected by the Target.
                                         * If blockoff != 0 error will be
                                         * inserted in middle of the IO.
                                         */

                                        lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                                        "9080 BLKGRD: Injecting apptag error: "
                                        "write lba x%lx + x%x oldappTag x%x\n",
                                        (unsigned long)lba, blockoff,
                                        be16_to_cpu(src->app_tag));

                                        /*
                                         * Save the old app_tag so we can
                                         * restore it on completion.
                                         */
                                        if (lpfc_cmd) {
                                                lpfc_cmd->prot_data_type =
                                                        LPFC_INJERR_APPTAG;
                                                lpfc_cmd->prot_data_segment =
                                                        src;
                                                lpfc_cmd->prot_data =
                                                        src->app_tag;
                                        }
                                        src->app_tag = cpu_to_be16(0xDEAD);
                                        phba->lpfc_injerr_wapp_cnt--;
                                        if (phba->lpfc_injerr_wapp_cnt == 0) {
                                                phba->lpfc_injerr_nportid = 0;
                                                phba->lpfc_injerr_lba =
                                                        LPFC_INJERR_LBA_OFF;
                                                memset(&phba->lpfc_injerr_wwpn,
                                                  0, sizeof(struct lpfc_name));
                                        }
                                        rc = BG_ERR_TGT | BG_ERR_CHECK;
                                        break;
                                }
                                /* Drop thru */
                        case SCSI_PROT_WRITE_INSERT:
                                /*
                                 * For WRITE_INSERT, force the
                                 * error to be sent on the wire. It should be
                                 * detected by the Target.
                                 */
                                /* DEAD will be the apptag on the wire */
                                *apptag = 0xDEAD;
                                phba->lpfc_injerr_wapp_cnt--;
                                if (phba->lpfc_injerr_wapp_cnt == 0) {
                                        phba->lpfc_injerr_nportid = 0;
                                        phba->lpfc_injerr_lba =
                                                LPFC_INJERR_LBA_OFF;
                                        memset(&phba->lpfc_injerr_wwpn,
                                                0, sizeof(struct lpfc_name));
                                }
                                rc = BG_ERR_TGT | BG_ERR_CHECK;

                                lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                                        "0813 BLKGRD: Injecting apptag error: "
                                        "write lba x%lx\n", (unsigned long)lba);
                                break;
                        case SCSI_PROT_WRITE_STRIP:
                                /*
                                 * For WRITE_STRIP and WRITE_PASS,
                                 * force the error on data
                                 * being copied from SLI-Host to SLI-Port.
                                 */
                                *apptag = 0xDEAD;
                                phba->lpfc_injerr_wapp_cnt--;
                                if (phba->lpfc_injerr_wapp_cnt == 0) {
                                        phba->lpfc_injerr_nportid = 0;
                                        phba->lpfc_injerr_lba =
                                                LPFC_INJERR_LBA_OFF;
                                        memset(&phba->lpfc_injerr_wwpn,
                                                0, sizeof(struct lpfc_name));
                                }
                                rc = BG_ERR_INIT;

                                lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                                        "0812 BLKGRD: Injecting apptag error: "
                                        "write lba x%lx\n", (unsigned long)lba);
                                break;
                        }
                }
                if (phba->lpfc_injerr_rapp_cnt) {
                        switch (op) {
                        case SCSI_PROT_READ_INSERT:
                        case SCSI_PROT_READ_STRIP:
                        case SCSI_PROT_READ_PASS:
                                /*
                                 * For READ_STRIP and READ_PASS, force the
                                 * error on data being read off the wire. It
                                 * should force an IO error to the driver.
                                 */
                                *apptag = 0xDEAD;
                                phba->lpfc_injerr_rapp_cnt--;
                                if (phba->lpfc_injerr_rapp_cnt == 0) {
                                        phba->lpfc_injerr_nportid = 0;
                                        phba->lpfc_injerr_lba =
                                                LPFC_INJERR_LBA_OFF;
                                        memset(&phba->lpfc_injerr_wwpn,
                                                0, sizeof(struct lpfc_name));
                                }
                                rc = BG_ERR_INIT;

                                lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                                        "0814 BLKGRD: Injecting apptag error: "
                                        "read lba x%lx\n", (unsigned long)lba);
                                break;
                        }
                }
        }


        /* Should we change the Guard Tag */
        if (new_guard) {
                if (phba->lpfc_injerr_wgrd_cnt) {
                        switch (op) {
                        case SCSI_PROT_WRITE_PASS:
                                rc = BG_ERR_CHECK;
                                /* Drop thru */

                        case SCSI_PROT_WRITE_INSERT:
                                /*
                                 * For WRITE_INSERT, force the
                                 * error to be sent on the wire. It should be
                                 * detected by the Target.
                                 */
                                phba->lpfc_injerr_wgrd_cnt--;
                                if (phba->lpfc_injerr_wgrd_cnt == 0) {
                                        phba->lpfc_injerr_nportid = 0;
                                        phba->lpfc_injerr_lba =
                                                LPFC_INJERR_LBA_OFF;
                                        memset(&phba->lpfc_injerr_wwpn,
                                                0, sizeof(struct lpfc_name));
                                }

                                rc |= BG_ERR_TGT | BG_ERR_SWAP;
                                /* Signals the caller to swap CRC->CSUM */

                                lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                                        "0817 BLKGRD: Injecting guard error: "
                                        "write lba x%lx\n", (unsigned long)lba);
                                break;
                        case SCSI_PROT_WRITE_STRIP:
                                /*
                                 * For WRITE_STRIP and WRITE_PASS,
                                 * force the error on data
                                 * being copied from SLI-Host to SLI-Port.
                                 */
                                phba->lpfc_injerr_wgrd_cnt--;
                                if (phba->lpfc_injerr_wgrd_cnt == 0) {
                                        phba->lpfc_injerr_nportid = 0;
                                        phba->lpfc_injerr_lba =
                                                LPFC_INJERR_LBA_OFF;
                                        memset(&phba->lpfc_injerr_wwpn,
                                                0, sizeof(struct lpfc_name));
                                }

                                rc = BG_ERR_INIT | BG_ERR_SWAP;
                                /* Signals the caller to swap CRC->CSUM */

                                lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                                        "0816 BLKGRD: Injecting guard error: "
                                        "write lba x%lx\n", (unsigned long)lba);
                                break;
                        }
                }
                if (phba->lpfc_injerr_rgrd_cnt) {
                        switch (op) {
                        case SCSI_PROT_READ_INSERT:
                        case SCSI_PROT_READ_STRIP:
                        case SCSI_PROT_READ_PASS:
                                /*
                                 * For READ_STRIP and READ_PASS, force the
                                 * error on data being read off the wire. It
                                 * should force an IO error to the driver.
                                 */
                                phba->lpfc_injerr_rgrd_cnt--;
                                if (phba->lpfc_injerr_rgrd_cnt == 0) {
                                        phba->lpfc_injerr_nportid = 0;
                                        phba->lpfc_injerr_lba =
                                                LPFC_INJERR_LBA_OFF;
                                        memset(&phba->lpfc_injerr_wwpn,
                                                0, sizeof(struct lpfc_name));
                                }

                                rc = BG_ERR_INIT | BG_ERR_SWAP;
                                /* Signals the caller to swap CRC->CSUM */

                                lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                                        "0818 BLKGRD: Injecting guard error: "
                                        "read lba x%lx\n", (unsigned long)lba);
                        }
                }
        }

        return rc;
}
#endif

/**
 * lpfc_sc_to_bg_opcodes - Determine the BlockGuard opcodes to be used with
 * the specified SCSI command.
 * @phba: The Hba for which this call is being executed.
 * @sc: The SCSI command to examine
 * @txopt: (out) BlockGuard operation for transmitted data
 * @rxopt: (out) BlockGuard operation for received data
 *
 * Returns: zero on success; non-zero if tx and/or rx op cannot be determined
 *
 **/
static int
lpfc_sc_to_bg_opcodes(struct lpfc_hba *phba, struct scsi_cmnd *sc,
                uint8_t *txop, uint8_t *rxop)
{
        uint8_t ret = 0;

        if (lpfc_cmd_guard_csum(sc)) {
                switch (scsi_get_prot_op(sc)) {
                case SCSI_PROT_READ_INSERT:
                case SCSI_PROT_WRITE_STRIP:
                        *rxop = BG_OP_IN_NODIF_OUT_CSUM;
                        *txop = BG_OP_IN_CSUM_OUT_NODIF;
                        break;

                case SCSI_PROT_READ_STRIP:
                case SCSI_PROT_WRITE_INSERT:
                        *rxop = BG_OP_IN_CRC_OUT_NODIF;
                        *txop = BG_OP_IN_NODIF_OUT_CRC;
                        break;

                case SCSI_PROT_READ_PASS:
                case SCSI_PROT_WRITE_PASS:
                        *rxop = BG_OP_IN_CRC_OUT_CSUM;
                        *txop = BG_OP_IN_CSUM_OUT_CRC;
                        break;

                case SCSI_PROT_NORMAL:
                default:
                        lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                                "9063 BLKGRD: Bad op/guard:%d/IP combination\n",
                                        scsi_get_prot_op(sc));
                        ret = 1;
                        break;

                }
        } else {
                switch (scsi_get_prot_op(sc)) {
                case SCSI_PROT_READ_STRIP:
                case SCSI_PROT_WRITE_INSERT:
                        *rxop = BG_OP_IN_CRC_OUT_NODIF;
                        *txop = BG_OP_IN_NODIF_OUT_CRC;
                        break;

                case SCSI_PROT_READ_PASS:
                case SCSI_PROT_WRITE_PASS:
                        *rxop = BG_OP_IN_CRC_OUT_CRC;
                        *txop = BG_OP_IN_CRC_OUT_CRC;
                        break;

                case SCSI_PROT_READ_INSERT:
                case SCSI_PROT_WRITE_STRIP:
                        *rxop = BG_OP_IN_NODIF_OUT_CRC;
                        *txop = BG_OP_IN_CRC_OUT_NODIF;
                        break;

                case SCSI_PROT_NORMAL:
                default:
                        lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                                "9075 BLKGRD: Bad op/guard:%d/CRC combination\n",
                                        scsi_get_prot_op(sc));
                        ret = 1;
                        break;
                }
        }

        return ret;
}

#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
/**
 * lpfc_bg_err_opcodes - reDetermine the BlockGuard opcodes to be used with
 * the specified SCSI command in order to force a guard tag error.
 * @phba: The Hba for which this call is being executed.
 * @sc: The SCSI command to examine
 * @txopt: (out) BlockGuard operation for transmitted data
 * @rxopt: (out) BlockGuard operation for received data
 *
 * Returns: zero on success; non-zero if tx and/or rx op cannot be determined
 *
 **/
static int
lpfc_bg_err_opcodes(struct lpfc_hba *phba, struct scsi_cmnd *sc,
                uint8_t *txop, uint8_t *rxop)
{
        uint8_t ret = 0;

        if (lpfc_cmd_guard_csum(sc)) {
                switch (scsi_get_prot_op(sc)) {
                case SCSI_PROT_READ_INSERT:
                case SCSI_PROT_WRITE_STRIP:
                        *rxop = BG_OP_IN_NODIF_OUT_CRC;
                        *txop = BG_OP_IN_CRC_OUT_NODIF;
                        break;

                case SCSI_PROT_READ_STRIP:
                case SCSI_PROT_WRITE_INSERT:
                        *rxop = BG_OP_IN_CSUM_OUT_NODIF;
                        *txop = BG_OP_IN_NODIF_OUT_CSUM;
                        break;

                case SCSI_PROT_READ_PASS:
                case SCSI_PROT_WRITE_PASS:
                        *rxop = BG_OP_IN_CSUM_OUT_CRC;
                        *txop = BG_OP_IN_CRC_OUT_CSUM;
                        break;

                case SCSI_PROT_NORMAL:
                default:
                        break;

                }
        } else {
                switch (scsi_get_prot_op(sc)) {
                case SCSI_PROT_READ_STRIP:
                case SCSI_PROT_WRITE_INSERT:
                        *rxop = BG_OP_IN_CSUM_OUT_NODIF;
                        *txop = BG_OP_IN_NODIF_OUT_CSUM;
                        break;

                case SCSI_PROT_READ_PASS:
                case SCSI_PROT_WRITE_PASS:
                        *rxop = BG_OP_IN_CSUM_OUT_CSUM;
                        *txop = BG_OP_IN_CSUM_OUT_CSUM;
                        break;

                case SCSI_PROT_READ_INSERT:
                case SCSI_PROT_WRITE_STRIP:
                        *rxop = BG_OP_IN_NODIF_OUT_CSUM;
                        *txop = BG_OP_IN_CSUM_OUT_NODIF;
                        break;

                case SCSI_PROT_NORMAL:
                default:
                        break;
                }
        }

        return ret;
}
#endif

/**
 * lpfc_bg_setup_bpl - Setup BlockGuard BPL with no protection data
 * @phba: The Hba for which this call is being executed.
 * @sc: pointer to scsi command we're working on
 * @bpl: pointer to buffer list for protection groups
 * @datacnt: number of segments of data that have been dma mapped
 *
 * This function sets up BPL buffer list for protection groups of
 * type LPFC_PG_TYPE_NO_DIF
 *
 * This is usually used when the HBA is instructed to generate
 * DIFs and insert them into data stream (or strip DIF from
 * incoming data stream)
 *
 * The buffer list consists of just one protection group described
 * below:
 *                                +-------------------------+
 *   start of prot group  -->     |          PDE_5          |
 *                                +-------------------------+
 *                                |          PDE_6          |
 *                                +-------------------------+
 *                                |         Data BDE        |
 *                                +-------------------------+
 *                                |more Data BDE's ... (opt)|
 *                                +-------------------------+
 *
 *
 * Note: Data s/g buffers have been dma mapped
 *
 * Returns the number of BDEs added to the BPL.
 **/
static int
lpfc_bg_setup_bpl(struct lpfc_hba *phba, struct scsi_cmnd *sc,
                struct ulp_bde64 *bpl, int datasegcnt)
{
        struct scatterlist *sgde = NULL; /* s/g data entry */
        struct lpfc_pde5 *pde5 = NULL;
        struct lpfc_pde6 *pde6 = NULL;
        dma_addr_t physaddr;
        int i = 0, num_bde = 0, status;
        int datadir = sc->sc_data_direction;
#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
        uint32_t rc;
#endif
        uint32_t checking = 1;
        uint32_t reftag;
        uint8_t txop, rxop;

        status  = lpfc_sc_to_bg_opcodes(phba, sc, &txop, &rxop);
        if (status)
                goto out;

        /* extract some info from the scsi command for pde*/
        reftag = (uint32_t)scsi_get_lba(sc); /* Truncate LBA */

#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
        rc = lpfc_bg_err_inject(phba, sc, &reftag, NULL, 1);
        if (rc) {
                if (rc & BG_ERR_SWAP)
                        lpfc_bg_err_opcodes(phba, sc, &txop, &rxop);
                if (rc & BG_ERR_CHECK)
                        checking = 0;
        }
#endif

        /* setup PDE5 with what we have */
        pde5 = (struct lpfc_pde5 *) bpl;
        memset(pde5, 0, sizeof(struct lpfc_pde5));
        bf_set(pde5_type, pde5, LPFC_PDE5_DESCRIPTOR);

        /* Endianness conversion if necessary for PDE5 */
        pde5->word0 = cpu_to_le32(pde5->word0);
        pde5->reftag = cpu_to_le32(reftag);

        /* advance bpl and increment bde count */
        num_bde++;
        bpl++;
        pde6 = (struct lpfc_pde6 *) bpl;

        /* setup PDE6 with the rest of the info */
        memset(pde6, 0, sizeof(struct lpfc_pde6));
        bf_set(pde6_type, pde6, LPFC_PDE6_DESCRIPTOR);
        bf_set(pde6_optx, pde6, txop);
        bf_set(pde6_oprx, pde6, rxop);

        /*
         * We only need to check the data on READs, for WRITEs
         * protection data is automatically generated, not checked.
         */
        if (datadir == DMA_FROM_DEVICE) {
                if (lpfc_cmd_protect(sc, LPFC_CHECK_PROTECT_GUARD))
                        bf_set(pde6_ce, pde6, checking);
                else
                        bf_set(pde6_ce, pde6, 0);

                if (lpfc_cmd_protect(sc, LPFC_CHECK_PROTECT_REF))
                        bf_set(pde6_re, pde6, checking);
                else
                        bf_set(pde6_re, pde6, 0);
        }
        bf_set(pde6_ai, pde6, 1);
        bf_set(pde6_ae, pde6, 0);
        bf_set(pde6_apptagval, pde6, 0);

        /* Endianness conversion if necessary for PDE6 */
        pde6->word0 = cpu_to_le32(pde6->word0);
        pde6->word1 = cpu_to_le32(pde6->word1);
        pde6->word2 = cpu_to_le32(pde6->word2);

        /* advance bpl and increment bde count */
        num_bde++;
        bpl++;

        /* assumption: caller has already run dma_map_sg on command data */
        scsi_for_each_sg(sc, sgde, datasegcnt, i) {
                physaddr = sg_dma_address(sgde);
                bpl->addrLow = le32_to_cpu(putPaddrLow(physaddr));
                bpl->addrHigh = le32_to_cpu(putPaddrHigh(physaddr));
                bpl->tus.f.bdeSize = sg_dma_len(sgde);
                if (datadir == DMA_TO_DEVICE)
                        bpl->tus.f.bdeFlags = BUFF_TYPE_BDE_64;
                else
                        bpl->tus.f.bdeFlags = BUFF_TYPE_BDE_64I;
                bpl->tus.w = le32_to_cpu(bpl->tus.w);
                bpl++;
                num_bde++;
        }

out:
        return num_bde;
}

/**
 * lpfc_bg_setup_bpl_prot - Setup BlockGuard BPL with protection data
 * @phba: The Hba for which this call is being executed.
 * @sc: pointer to scsi command we're working on
 * @bpl: pointer to buffer list for protection groups
 * @datacnt: number of segments of data that have been dma mapped
 * @protcnt: number of segment of protection data that have been dma mapped

 *
 * This function sets up BPL buffer list for protection groups of
 * type LPFC_PG_TYPE_DIF
 *
 * This is usually used when DIFs are in their own buffers,
 * separate from the data. The HBA can then by instructed
 * to place the DIFs in the outgoing stream.  For read operations,
 * The HBA could extract the DIFs and place it in DIF buffers.
 *
 * The buffer list for this type consists of one or more of the
 * protection groups described below:
 *                                    +-------------------------+
 *   start of first prot group  -->   |          PDE_5          |
 *                                    +-------------------------+
 *                                    |          PDE_6          |
 *                                    +-------------------------+
 *                                    |      PDE_7 (Prot BDE)   |
 *                                    +-------------------------+
 *                                    |        Data BDE         |
 *                                    +-------------------------+
 *                                    |more Data BDE's ... (opt)|
 *                                    +-------------------------+
 *   start of new  prot group  -->    |          PDE_5          |
 *                                    +-------------------------+
 *                                    |          ...            |
 *                                    +-------------------------+
 *
 * Note: It is assumed that both data and protection s/g buffers have been
 *       mapped for DMA
 *
 * Returns the number of BDEs added to the BPL.
 **/
static int
lpfc_bg_setup_bpl_prot(struct lpfc_hba *phba, struct scsi_cmnd *sc,
                struct ulp_bde64 *bpl, int datacnt, int protcnt)
{
        struct scatterlist *sgde = NULL; /* s/g data entry */
        struct scatterlist *sgpe = NULL; /* s/g prot entry */
        struct lpfc_pde5 *pde5 = NULL;
        struct lpfc_pde6 *pde6 = NULL;
        struct lpfc_pde7 *pde7 = NULL;
        dma_addr_t dataphysaddr, protphysaddr;
        unsigned short curr_data = 0, curr_prot = 0;
        unsigned int split_offset;
        unsigned int protgroup_len, protgroup_offset = 0, protgroup_remainder;
        unsigned int protgrp_blks, protgrp_bytes;
        unsigned int remainder, subtotal;
        int status;
        int datadir = sc->sc_data_direction;
        unsigned char pgdone = 0, alldone = 0;
        unsigned blksize;
#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
        uint32_t rc;
#endif
        uint32_t checking = 1;
        uint32_t reftag;
        uint8_t txop, rxop;
        int num_bde = 0;

        sgpe = scsi_prot_sglist(sc);
        sgde = scsi_sglist(sc);

        if (!sgpe || !sgde) {
                lpfc_printf_log(phba, KERN_ERR, LOG_FCP,
                                "9020 Invalid s/g entry: data=0x%p prot=0x%p\n",
                                sgpe, sgde);
                return 0;
        }

        status = lpfc_sc_to_bg_opcodes(phba, sc, &txop, &rxop);
        if (status)
                goto out;

        /* extract some info from the scsi command */
        blksize = lpfc_cmd_blksize(sc);
        reftag = (uint32_t)scsi_get_lba(sc); /* Truncate LBA */

#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
        rc = lpfc_bg_err_inject(phba, sc, &reftag, NULL, 1);
        if (rc) {
                if (rc & BG_ERR_SWAP)
                        lpfc_bg_err_opcodes(phba, sc, &txop, &rxop);
                if (rc & BG_ERR_CHECK)
                        checking = 0;
        }
#endif

        split_offset = 0;
        do {
                /* Check to see if we ran out of space */
                if (num_bde >= (phba->cfg_total_seg_cnt - 2))
                        return num_bde + 3;

                /* setup PDE5 with what we have */
                pde5 = (struct lpfc_pde5 *) bpl;
                memset(pde5, 0, sizeof(struct lpfc_pde5));
                bf_set(pde5_type, pde5, LPFC_PDE5_DESCRIPTOR);

                /* Endianness conversion if necessary for PDE5 */
                pde5->word0 = cpu_to_le32(pde5->word0);
                pde5->reftag = cpu_to_le32(reftag);

                /* advance bpl and increment bde count */
                num_bde++;
                bpl++;
                pde6 = (struct lpfc_pde6 *) bpl;

                /* setup PDE6 with the rest of the info */
                memset(pde6, 0, sizeof(struct lpfc_pde6));
                bf_set(pde6_type, pde6, LPFC_PDE6_DESCRIPTOR);
                bf_set(pde6_optx, pde6, txop);
                bf_set(pde6_oprx, pde6, rxop);

                if (lpfc_cmd_protect(sc, LPFC_CHECK_PROTECT_GUARD))
                        bf_set(pde6_ce, pde6, checking);
                else
                        bf_set(pde6_ce, pde6, 0);

                if (lpfc_cmd_protect(sc, LPFC_CHECK_PROTECT_REF))
                        bf_set(pde6_re, pde6, checking);
                else
                        bf_set(pde6_re, pde6, 0);

                bf_set(pde6_ai, pde6, 1);
                bf_set(pde6_ae, pde6, 0);
                bf_set(pde6_apptagval, pde6, 0);

                /* Endianness conversion if necessary for PDE6 */
                pde6->word0 = cpu_to_le32(pde6->word0);
                pde6->word1 = cpu_to_le32(pde6->word1);
                pde6->word2 = cpu_to_le32(pde6->word2);

                /* advance bpl and increment bde count */
                num_bde++;
                bpl++;

                /* setup the first BDE that points to protection buffer */
                protphysaddr = sg_dma_address(sgpe) + protgroup_offset;
                protgroup_len = sg_dma_len(sgpe) - protgroup_offset;

                /* must be integer multiple of the DIF block length */
                BUG_ON(protgroup_len % 8);

                pde7 = (struct lpfc_pde7 *) bpl;
                memset(pde7, 0, sizeof(struct lpfc_pde7));
                bf_set(pde7_type, pde7, LPFC_PDE7_DESCRIPTOR);

                pde7->addrHigh = le32_to_cpu(putPaddrHigh(protphysaddr));
                pde7->addrLow = le32_to_cpu(putPaddrLow(protphysaddr));

                protgrp_blks = protgroup_len / 8;
                protgrp_bytes = protgrp_blks * blksize;

                /* check if this pde is crossing the 4K boundary; if so split */
                if ((pde7->addrLow & 0xfff) + protgroup_len > 0x1000) {
                        protgroup_remainder = 0x1000 - (pde7->addrLow & 0xfff);
                        protgroup_offset += protgroup_remainder;
                        protgrp_blks = protgroup_remainder / 8;
                        protgrp_bytes = protgrp_blks * blksize;
                } else {
                        protgroup_offset = 0;
                        curr_prot++;
                }

                num_bde++;

                /* setup BDE's for data blocks associated with DIF data */
                pgdone = 0;
                subtotal = 0; /* total bytes processed for current prot grp */
                while (!pgdone) {
                        /* Check to see if we ran out of space */
                        if (num_bde >= phba->cfg_total_seg_cnt)
                                return num_bde + 1;

                        if (!sgde) {
                                lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                                        "9065 BLKGRD:%s Invalid data segment\n",
                                                __func__);
                                return 0;
                        }
                        bpl++;
                        dataphysaddr = sg_dma_address(sgde) + split_offset;
                        bpl->addrLow = le32_to_cpu(putPaddrLow(dataphysaddr));
                        bpl->addrHigh = le32_to_cpu(putPaddrHigh(dataphysaddr));

                        remainder = sg_dma_len(sgde) - split_offset;

                        if ((subtotal + remainder) <= protgrp_bytes) {
                                /* we can use this whole buffer */
                                bpl->tus.f.bdeSize = remainder;
                                split_offset = 0;

                                if ((subtotal + remainder) == protgrp_bytes)
                                        pgdone = 1;
                        } else {
                                /* must split this buffer with next prot grp */
                                bpl->tus.f.bdeSize = protgrp_bytes - subtotal;
                                split_offset += bpl->tus.f.bdeSize;
                        }

                        subtotal += bpl->tus.f.bdeSize;

                        if (datadir == DMA_TO_DEVICE)
                                bpl->tus.f.bdeFlags = BUFF_TYPE_BDE_64;
                        else
                                bpl->tus.f.bdeFlags = BUFF_TYPE_BDE_64I;
                        bpl->tus.w = le32_to_cpu(bpl->tus.w);

                        num_bde++;
                        curr_data++;

                        if (split_offset)
                                break;

                        /* Move to the next s/g segment if possible */
                        sgde = sg_next(sgde);

                }

                if (protgroup_offset) {
                        /* update the reference tag */
                        reftag += protgrp_blks;
                        bpl++;
                        continue;
                }

                /* are we done ? */
                if (curr_prot == protcnt) {
                        alldone = 1;
                } else if (curr_prot < protcnt) {
                        /* advance to next prot buffer */
                        sgpe = sg_next(sgpe);
                        bpl++;

                        /* update the reference tag */
                        reftag += protgrp_blks;
                } else {
                        /* if we're here, we have a bug */
                        lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                                "9054 BLKGRD: bug in %s\n", __func__);
                }

        } while (!alldone);
out:

        return num_bde;
}

/**
 * lpfc_bg_setup_sgl - Setup BlockGuard SGL with no protection data
 * @phba: The Hba for which this call is being executed.
 * @sc: pointer to scsi command we're working on
 * @sgl: pointer to buffer list for protection groups
 * @datacnt: number of segments of data that have been dma mapped
 *
 * This function sets up SGL buffer list for protection groups of
 * type LPFC_PG_TYPE_NO_DIF
 *
 * This is usually used when the HBA is instructed to generate
 * DIFs and insert them into data stream (or strip DIF from
 * incoming data stream)
 *
 * The buffer list consists of just one protection group described
 * below:
 *                                +-------------------------+
 *   start of prot group  -->     |         DI_SEED         |
 *                                +-------------------------+
 *                                |         Data SGE        |
 *                                +-------------------------+
 *                                |more Data SGE's ... (opt)|
 *                                +-------------------------+
 *
 *
 * Note: Data s/g buffers have been dma mapped
 *
 * Returns the number of SGEs added to the SGL.
 **/
static int
lpfc_bg_setup_sgl(struct lpfc_hba *phba, struct scsi_cmnd *sc,
                struct sli4_sge *sgl, int datasegcnt)
{
        struct scatterlist *sgde = NULL; /* s/g data entry */
        struct sli4_sge_diseed *diseed = NULL;
        dma_addr_t physaddr;
        int i = 0, num_sge = 0, status;
        uint32_t reftag;
        uint8_t txop, rxop;
#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
        uint32_t rc;
#endif
        uint32_t checking = 1;
        uint32_t dma_len;
        uint32_t dma_offset = 0;

        status  = lpfc_sc_to_bg_opcodes(phba, sc, &txop, &rxop);
        if (status)
                goto out;

        /* extract some info from the scsi command for pde*/
        reftag = (uint32_t)scsi_get_lba(sc); /* Truncate LBA */

#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
        rc = lpfc_bg_err_inject(phba, sc, &reftag, NULL, 1);
        if (rc) {
                if (rc & BG_ERR_SWAP)
                        lpfc_bg_err_opcodes(phba, sc, &txop, &rxop);
                if (rc & BG_ERR_CHECK)
                        checking = 0;
        }
#endif

        /* setup DISEED with what we have */
        diseed = (struct sli4_sge_diseed *) sgl;
        memset(diseed, 0, sizeof(struct sli4_sge_diseed));
        bf_set(lpfc_sli4_sge_type, sgl, LPFC_SGE_TYPE_DISEED);

        /* Endianness conversion if necessary */
        diseed->ref_tag = cpu_to_le32(reftag);
        diseed->ref_tag_tran = diseed->ref_tag;

        /*
         * We only need to check the data on READs, for WRITEs
         * protection data is automatically generated, not checked.
         */
        if (sc->sc_data_direction == DMA_FROM_DEVICE) {
                if (lpfc_cmd_protect(sc, LPFC_CHECK_PROTECT_GUARD))
                        bf_set(lpfc_sli4_sge_dif_ce, diseed, checking);
                else
                        bf_set(lpfc_sli4_sge_dif_ce, diseed, 0);

                if (lpfc_cmd_protect(sc, LPFC_CHECK_PROTECT_REF))
                        bf_set(lpfc_sli4_sge_dif_re, diseed, checking);
                else
                        bf_set(lpfc_sli4_sge_dif_re, diseed, 0);
        }

        /* setup DISEED with the rest of the info */
        bf_set(lpfc_sli4_sge_dif_optx, diseed, txop);
        bf_set(lpfc_sli4_sge_dif_oprx, diseed, rxop);

        bf_set(lpfc_sli4_sge_dif_ai, diseed, 1);
        bf_set(lpfc_sli4_sge_dif_me, diseed, 0);

        /* Endianness conversion if necessary for DISEED */
        diseed->word2 = cpu_to_le32(diseed->word2);
        diseed->word3 = cpu_to_le32(diseed->word3);

        /* advance bpl and increment sge count */
        num_sge++;
        sgl++;

        /* assumption: caller has already run dma_map_sg on command data */
        scsi_for_each_sg(sc, sgde, datasegcnt, i) {
                physaddr = sg_dma_address(sgde);
                dma_len = sg_dma_len(sgde);
                sgl->addr_lo = cpu_to_le32(putPaddrLow(physaddr));
                sgl->addr_hi = cpu_to_le32(putPaddrHigh(physaddr));
                if ((i + 1) == datasegcnt)
                        bf_set(lpfc_sli4_sge_last, sgl, 1);
                else
                        bf_set(lpfc_sli4_sge_last, sgl, 0);
                bf_set(lpfc_sli4_sge_offset, sgl, dma_offset);
                bf_set(lpfc_sli4_sge_type, sgl, LPFC_SGE_TYPE_DATA);

                sgl->sge_len = cpu_to_le32(dma_len);
                dma_offset += dma_len;

                sgl++;
                num_sge++;
        }

out:
        return num_sge;
}

/**
 * lpfc_bg_setup_sgl_prot - Setup BlockGuard SGL with protection data
 * @phba: The Hba for which this call is being executed.
 * @sc: pointer to scsi command we're working on
 * @sgl: pointer to buffer list for protection groups
 * @datacnt: number of segments of data that have been dma mapped
 * @protcnt: number of segment of protection data that have been dma mapped
 *
 * This function sets up SGL buffer list for protection groups of
 * type LPFC_PG_TYPE_DIF
 *
 * This is usually used when DIFs are in their own buffers,
 * separate from the data. The HBA can then by instructed
 * to place the DIFs in the outgoing stream.  For read operations,
 * The HBA could extract the DIFs and place it in DIF buffers.
 *
 * The buffer list for this type consists of one or more of the
 * protection groups described below:
 *                                    +-------------------------+
 *   start of first prot group  -->   |         DISEED          |
 *                                    +-------------------------+
 *                                    |      DIF (Prot SGE)     |
 *                                    +-------------------------+
 *                                    |        Data SGE         |
 *                                    +-------------------------+
 *                                    |more Data SGE's ... (opt)|
 *                                    +-------------------------+
 *   start of new  prot group  -->    |         DISEED          |
 *                                    +-------------------------+
 *                                    |          ...            |
 *                                    +-------------------------+
 *
 * Note: It is assumed that both data and protection s/g buffers have been
 *       mapped for DMA
 *
 * Returns the number of SGEs added to the SGL.
 **/
static int
lpfc_bg_setup_sgl_prot(struct lpfc_hba *phba, struct scsi_cmnd *sc,
                struct sli4_sge *sgl, int datacnt, int protcnt)
{
        struct scatterlist *sgde = NULL; /* s/g data entry */
        struct scatterlist *sgpe = NULL; /* s/g prot entry */
        struct sli4_sge_diseed *diseed = NULL;
        dma_addr_t dataphysaddr, protphysaddr;
        unsigned short curr_data = 0, curr_prot = 0;
        unsigned int split_offset;
        unsigned int protgroup_len, protgroup_offset = 0, protgroup_remainder;
        unsigned int protgrp_blks, protgrp_bytes;
        unsigned int remainder, subtotal;
        int status;
        unsigned char pgdone = 0, alldone = 0;
        unsigned blksize;
        uint32_t reftag;
        uint8_t txop, rxop;
        uint32_t dma_len;
#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
        uint32_t rc;
#endif
        uint32_t checking = 1;
        uint32_t dma_offset = 0;
        int num_sge = 0;

        sgpe = scsi_prot_sglist(sc);
        sgde = scsi_sglist(sc);

        if (!sgpe || !sgde) {
                lpfc_printf_log(phba, KERN_ERR, LOG_FCP,
                                "9082 Invalid s/g entry: data=0x%p prot=0x%p\n",
                                sgpe, sgde);
                return 0;
        }

        status = lpfc_sc_to_bg_opcodes(phba, sc, &txop, &rxop);
        if (status)
                goto out;

        /* extract some info from the scsi command */
        blksize = lpfc_cmd_blksize(sc);
        reftag = (uint32_t)scsi_get_lba(sc); /* Truncate LBA */

#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
        rc = lpfc_bg_err_inject(phba, sc, &reftag, NULL, 1);
        if (rc) {
                if (rc & BG_ERR_SWAP)
                        lpfc_bg_err_opcodes(phba, sc, &txop, &rxop);
                if (rc & BG_ERR_CHECK)
                        checking = 0;
        }
#endif

        split_offset = 0;
        do {
                /* Check to see if we ran out of space */
                if (num_sge >= (phba->cfg_total_seg_cnt - 2))
                        return num_sge + 3;

                /* setup DISEED with what we have */
                diseed = (struct sli4_sge_diseed *) sgl;
                memset(diseed, 0, sizeof(struct sli4_sge_diseed));
                bf_set(lpfc_sli4_sge_type, sgl, LPFC_SGE_TYPE_DISEED);

                /* Endianness conversion if necessary */
                diseed->ref_tag = cpu_to_le32(reftag);
                diseed->ref_tag_tran = diseed->ref_tag;

                if (lpfc_cmd_protect(sc, LPFC_CHECK_PROTECT_GUARD)) {
                        bf_set(lpfc_sli4_sge_dif_ce, diseed, checking);

                } else {
                        bf_set(lpfc_sli4_sge_dif_ce, diseed, 0);
                        /*
                         * When in this mode, the hardware will replace
                         * the guard tag from the host with a
                         * newly generated good CRC for the wire.
                         * Switch to raw mode here to avoid this
                         * behavior. What the host sends gets put on the wire.
                         */
                        if (txop == BG_OP_IN_CRC_OUT_CRC) {
                                txop = BG_OP_RAW_MODE;
                                rxop = BG_OP_RAW_MODE;
                        }
                }


                if (lpfc_cmd_protect(sc, LPFC_CHECK_PROTECT_REF))
                        bf_set(lpfc_sli4_sge_dif_re, diseed, checking);
                else
                        bf_set(lpfc_sli4_sge_dif_re, diseed, 0);

                /* setup DISEED with the rest of the info */
                bf_set(lpfc_sli4_sge_dif_optx, diseed, txop);
                bf_set(lpfc_sli4_sge_dif_oprx, diseed, rxop);

                bf_set(lpfc_sli4_sge_dif_ai, diseed, 1);
                bf_set(lpfc_sli4_sge_dif_me, diseed, 0);

                /* Endianness conversion if necessary for DISEED */
                diseed->word2 = cpu_to_le32(diseed->word2);
                diseed->word3 = cpu_to_le32(diseed->word3);

                /* advance sgl and increment bde count */
                num_sge++;
                sgl++;

                /* setup the first BDE that points to protection buffer */
                protphysaddr = sg_dma_address(sgpe) + protgroup_offset;
                protgroup_len = sg_dma_len(sgpe) - protgroup_offset;

                /* must be integer multiple of the DIF block length */
                BUG_ON(protgroup_len % 8);

                /* Now setup DIF SGE */
                sgl->word2 = 0;
                bf_set(lpfc_sli4_sge_type, sgl, LPFC_SGE_TYPE_DIF);
                sgl->addr_hi = le32_to_cpu(putPaddrHigh(protphysaddr));
                sgl->addr_lo = le32_to_cpu(putPaddrLow(protphysaddr));
                sgl->word2 = cpu_to_le32(sgl->word2);

                protgrp_blks = protgroup_len / 8;
                protgrp_bytes = protgrp_blks * blksize;

                /* check if DIF SGE is crossing the 4K boundary; if so split */
                if ((sgl->addr_lo & 0xfff) + protgroup_len > 0x1000) {
                        protgroup_remainder = 0x1000 - (sgl->addr_lo & 0xfff);
                        protgroup_offset += protgroup_remainder;
                        protgrp_blks = protgroup_remainder / 8;
                        protgrp_bytes = protgrp_blks * blksize;
                } else {
                        protgroup_offset = 0;
                        curr_prot++;
                }

                num_sge++;

                /* setup SGE's for data blocks associated with DIF data */
                pgdone = 0;
                subtotal = 0; /* total bytes processed for current prot grp */
                while (!pgdone) {
                        /* Check to see if we ran out of space */
                        if (num_sge >= phba->cfg_total_seg_cnt)
                                return num_sge + 1;

                        if (!sgde) {
                                lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                                        "9086 BLKGRD:%s Invalid data segment\n",
                                                __func__);
                                return 0;
                        }
                        sgl++;
                        dataphysaddr = sg_dma_address(sgde) + split_offset;

                        remainder = sg_dma_len(sgde) - split_offset;

                        if ((subtotal + remainder) <= protgrp_bytes) {
                                /* we can use this whole buffer */
                                dma_len = remainder;
                                split_offset = 0;

                                if ((subtotal + remainder) == protgrp_bytes)
                                        pgdone = 1;
                        } else {
                                /* must split this buffer with next prot grp */
                                dma_len = protgrp_bytes - subtotal;
                                split_offset += dma_len;
                        }

                        subtotal += dma_len;

                        sgl->addr_lo = cpu_to_le32(putPaddrLow(dataphysaddr));
                        sgl->addr_hi = cpu_to_le32(putPaddrHigh(dataphysaddr));
                        bf_set(lpfc_sli4_sge_last, sgl, 0);
                        bf_set(lpfc_sli4_sge_offset, sgl, dma_offset);
                        bf_set(lpfc_sli4_sge_type, sgl, LPFC_SGE_TYPE_DATA);

                        sgl->sge_len = cpu_to_le32(dma_len);
                        dma_offset += dma_len;

                        num_sge++;
                        curr_data++;

                        if (split_offset)
                                break;

                        /* Move to the next s/g segment if possible */
                        sgde = sg_next(sgde);
                }

                if (protgroup_offset) {
                        /* update the reference tag */
                        reftag += protgrp_blks;
                        sgl++;
                        continue;
                }

                /* are we done ? */
                if (curr_prot == protcnt) {
                        bf_set(lpfc_sli4_sge_last, sgl, 1);
                        alldone = 1;
                } else if (curr_prot < protcnt) {
                        /* advance to next prot buffer */
                        sgpe = sg_next(sgpe);
                        sgl++;

                        /* update the reference tag */
                        reftag += protgrp_blks;
                } else {
                        /* if we're here, we have a bug */
                        lpfc_printf_log(phba, KERN_ERR, LOG_BG,
                                "9085 BLKGRD: bug in %s\n", __func__);
                }

        } while (!alldone);

out:

        return num_sge;
}

/**
 * lpfc_prot_group_type - Get prtotection group type of SCSI command
 * @phba: The Hba for which this call is being executed.
 * @sc: pointer to scsi command we're working on
 *
 * Given a SCSI command that supports DIF, determine composition of protection
 * groups involved in setting up buffer lists
 *
 * Returns: Protection group type (with or without DIF)
 *
 **/
static int
lpfc_prot_group_type(struct lpfc_hba *phba, struct scsi_cmnd *sc)
{
        int ret = LPFC_PG_TYPE_INVALID;
        unsigned char op = scsi_get_prot_op(sc);

        switch (op) {
        case SCSI_PROT_READ_STRIP:
        case SCSI_PROT_WRITE_INSERT:
                ret = LPFC_PG_TYPE_NO_DIF;
                break;
        case SCSI_PROT_READ_INSERT:
        case SCSI_PROT_WRITE_STRIP:
        case SCSI_PROT_READ_PASS:
        case SCSI_PROT_WRITE_PASS:
                ret = LPFC_PG_TYPE_DIF_BUF;
                break;
        default:
                if (phba)
                        lpfc_printf_log(phba, KERN_ERR, LOG_FCP,
                                        "9021 Unsupported protection op:%d\n",
                                        op);
                break;
        }
        return ret;
}

/**
 * lpfc_bg_scsi_adjust_dl - Adjust SCSI data length for BlockGuard
 * @phba: The Hba for which this call is being executed.
 * @lpfc_cmd: The scsi buffer which is going to be adjusted.
 *
 * Adjust the data length to account for how much data
 * is actually on the wire.
 *
 * returns the adjusted data length
 **/
static int
lpfc_bg_scsi_adjust_dl(struct lpfc_hba *phba,
                       struct lpfc_scsi_buf *lpfc_cmd)
{
        struct scsi_cmnd *sc = lpfc_cmd->pCmd;
        int fcpdl;

        fcpdl = scsi_bufflen(sc);

        /* Check if there is protection data on the wire */
        if (sc->sc_data_direction == DMA_FROM_DEVICE) {
                /* Read check for protection data */
                if (scsi_get_prot_op(sc) ==  SCSI_PROT_READ_INSERT)
                        return fcpdl;

        } else {
                /* Write check for protection data */
                if (scsi_get_prot_op(sc) ==  SCSI_PROT_WRITE_STRIP)
                        return fcpdl;
        }

        /*
         * If we are in DIF Type 1 mode every data block has a 8 byte
         * DIF (trailer) attached to it. Must ajust FCP data length
         * to account for the protection data.
         */
        fcpdl += (fcpdl / lpfc_cmd_blksize(sc)) * 8;

        return fcpdl;
}

/**
 * lpfc_bg_scsi_prep_dma_buf_s3 - DMA mapping for scsi buffer to SLI3 IF spec
 * @phba: The Hba for which this call is being executed.
 * @lpfc_cmd: The scsi buffer which is going to be prep'ed.
 *
 * This is the protection/DIF aware version of
 * lpfc_scsi_prep_dma_buf(). It may be a good idea to combine the
 * two functions eventually, but for now, it's here
 **/
static int
lpfc_bg_scsi_prep_dma_buf_s3(struct lpfc_hba *phba,
                struct lpfc_scsi_buf *lpfc_cmd)
{
        struct scsi_cmnd *scsi_cmnd = lpfc_cmd->pCmd;
        struct fcp_cmnd *fcp_cmnd = lpfc_cmd->fcp_cmnd;
        struct ulp_bde64 *bpl = lpfc_cmd->fcp_bpl;
        IOCB_t *iocb_cmd = &lpfc_cmd->cur_iocbq.iocb;
        uint32_t num_bde = 0;
        int datasegcnt, protsegcnt, datadir = scsi_cmnd->sc_data_direction;
        int prot_group_type = 0;
        int fcpdl;

        /*
         * Start the lpfc command prep by bumping the bpl beyond fcp_cmnd
         *  fcp_rsp regions to the first data bde entry
         */
        bpl += 2;
        if (scsi_sg_count(scsi_cmnd)) {
                /*
                 * The driver stores the segment count returned from pci_map_sg
                 * because this a count of dma-mappings used to map the use_sg
                 * pages.  They are not guaranteed to be the same for those
                 * architectures that implement an IOMMU.
                 */
                datasegcnt = dma_map_sg(&phba->pcidev->dev,
                                        scsi_sglist(scsi_cmnd),
                                        scsi_sg_count(scsi_cmnd), datadir);
                if (unlikely(!datasegcnt))
                        return 1;

                lpfc_cmd->seg_cnt = datasegcnt;

                /* First check if data segment count from SCSI Layer is good */
                if (lpfc_cmd->seg_cnt > phba->cfg_sg_seg_cnt)
                        goto err;

                prot_group_type = lpfc_prot_group_type(phba, scsi_cmnd);

                switch (prot_group_type) {
                case LPFC_PG_TYPE_NO_DIF:

                        /* Here we need to add a PDE5 and PDE6 to the count */
                        if ((lpfc_cmd->seg_cnt + 2) > phba->cfg_total_seg_cnt)
                                goto err;

                        num_bde = lpfc_bg_setup_bpl(phba, scsi_cmnd, bpl,
                                        datasegcnt);
                        /* we should have 2 or more entries in buffer list */
                        if (num_bde < 2)
                                goto err;
                        break;

                case LPFC_PG_TYPE_DIF_BUF:
                        /*
                         * This type indicates that protection buffers are
                         * passed to the driver, so that needs to be prepared
                         * for DMA
                         */
                        protsegcnt = dma_map_sg(&phba->pcidev->dev,
                                        scsi_prot_sglist(scsi_cmnd),
                                        scsi_prot_sg_count(scsi_cmnd), datadir);
                        if (unlikely(!protsegcnt)) {
                                scsi_dma_unmap(scsi_cmnd);
                                return 1;
                        }

                        lpfc_cmd->prot_seg_cnt = protsegcnt;

                        /*
                         * There is a minimun of 4 BPLs used for every
                         * protection data segment.
                         */
                        if ((lpfc_cmd->prot_seg_cnt * 4) >
                            (phba->cfg_total_seg_cnt - 2))
                                goto err;

                        num_bde = lpfc_bg_setup_bpl_prot(phba, scsi_cmnd, bpl,
                                        datasegcnt, protsegcnt);
                        /* we should have 3 or more entries in buffer list */
                        if ((num_bde < 3) ||
                            (num_bde > phba->cfg_total_seg_cnt))
                                goto err;
                        break;

                case LPFC_PG_TYPE_INVALID:
                default:
                        scsi_dma_unmap(scsi_cmnd);
                        lpfc_cmd->seg_cnt = 0;

                        lpfc_printf_log(phba, KERN_ERR, LOG_FCP,
                                        "9022 Unexpected protection group %i\n",
                                        prot_group_type);
                        return 1;
                }
        }

        /*
         * Finish initializing those IOCB fields that are dependent on the
         * scsi_cmnd request_buffer.  Note that the bdeSize is explicitly
         * reinitialized since all iocb memory resources are used many times
         * for transmit, receive, and continuation bpl's.
         */
        iocb_cmd->un.fcpi64.bdl.bdeSize = (2 * sizeof(struct ulp_bde64));
        iocb_cmd->un.fcpi64.bdl.bdeSize += (num_bde * sizeof(struct ulp_bde64));
        iocb_cmd->ulpBdeCount = 1;
        iocb_cmd->ulpLe = 1;

        fcpdl = lpfc_bg_scsi_adjust_dl(phba, lpfc_cmd);
        fcp_cmnd->fcpDl = be32_to_cpu(fcpdl);

        /*
         * Due to difference in data length between DIF/non-DIF paths,
         * we need to set word 4 of IOCB here
         */
        iocb_cmd->un.fcpi.fcpi_parm = fcpdl;

        return 0;
err:
        if (lpfc_cmd->seg_cnt)
                scsi_dma_unmap(scsi_cmnd);
        if (lpfc_cmd->prot_seg_cnt)
                dma_unmap_sg(&phba->pcidev->dev, scsi_prot_sglist(scsi_cmnd),
                             scsi_prot_sg_count(scsi_cmnd),
                             scsi_cmnd->sc_data_direction);

        lpfc_printf_log(phba, KERN_ERR, LOG_FCP,
                        "9023 Cannot setup S/G List for HBA"
                        "IO segs %d/%d BPL %d SCSI %d: %d %d\n",
                        lpfc_cmd->seg_cnt, lpfc_cmd->prot_seg_cnt,
                        phba->cfg_total_seg_cnt, phba->cfg_sg_seg_cnt,
                        prot_group_type, num_bde);

        lpfc_cmd->seg_cnt = 0;
        lpfc_cmd->prot_seg_cnt = 0;
        return 1;
}

/*
 * This function calcuates the T10 DIF guard tag
 * on the specified data using a CRC algorithmn
 * using crc_t10dif.
 */
static uint16_t
lpfc_bg_crc(uint8_t *data, int count)
{
        uint16_t crc = 0;
        uint16_t x;

        crc = crc_t10dif(data, count);
        x = cpu_to_be16(crc);
        return x;
}

/*
 * This function calcuates the T10 DIF guard tag
 * on the specified data using a CSUM algorithmn
 * using ip_compute_csum.
 */
static uint16_t
lpfc_bg_csum(uint8_t *data, int count)
{
        uint16_t ret;

        ret = ip_compute_csum(data, count);
        return ret;
}

/*
 * This function examines the protection data to try to determine
 * what type of T10-DIF error occurred.
 */
static void
lpfc_calc_bg_err(struct lpfc_hba *phba, struct lpfc_scsi_buf *lpfc_cmd)
{
        struct scatterlist *sgpe; /* s/g prot entry */
        struct scatterlist *sgde; /* s/g data entry */
        struct scsi_cmnd *cmd = lpfc_cmd->pCmd;
        struct scsi_dif_tuple *src = NULL;
        uint8_t *data_src = NULL;
        uint16_t guard_tag;
        uint16_t start_app_tag, app_tag;
        uint32_t start_ref_tag, ref_tag;
        int prot, protsegcnt;
        int err_type, len, data_len;
        int chk_ref, chk_app, chk_guard;
        uint16_t sum;
        unsigned blksize;

        err_type = BGS_GUARD_ERR_MASK;
        sum = 0;
        guard_tag = 0;

        /* First check to see if there is protection data to examine */
        prot = scsi_get_prot_op(cmd);
        if ((prot == SCSI_PROT_READ_STRIP) ||
            (prot == SCSI_PROT_WRITE_INSERT) ||
            (prot == SCSI_PROT_NORMAL))
                goto out;

        /* Currently the driver just supports ref_tag and guard_tag checking */
        chk_ref = 1;
        chk_app = 0;
        chk_guard = 0;

        /* Setup a ptr to the protection data provided by the SCSI host */
        sgpe = scsi_prot_sglist(cmd);
        protsegcnt = lpfc_cmd->prot_seg_cnt;

        if (sgpe && protsegcnt) {

                /*
                 * We will only try to verify guard tag if the segment
                 * data length is a multiple of the blksize.
                 */
                sgde = scsi_sglist(cmd);
                blksize = lpfc_cmd_blksize(cmd);
                data_src = (uint8_t *)sg_virt(sgde);
                data_len = sgde->length;
                if ((data_len & (blksize - 1)) == 0)
                        chk_guard = 1;

                src = (struct scsi_dif_tuple *)sg_virt(sgpe);
                start_ref_tag = (uint32_t)scsi_get_lba(cmd); /* Truncate LBA */
                start_app_tag = src->app_tag;
                len = sgpe->length;
                while (src && protsegcnt) {
                        while (len) {

                                /*
                                 * First check to see if a protection data
                                 * check is valid
                                 */
                                if ((src->ref_tag == T10_PI_REF_ESCAPE) ||
                                    (src->app_tag == T10_PI_APP_ESCAPE)) {
                                        start_ref_tag++;
                                        goto skipit;
                                }

                                /* First Guard Tag checking */
                                if (chk_guard) {
                                        guard_tag = src->guard_tag;
                                        if (lpfc_cmd_guard_csum(cmd))
                                                sum = lpfc_bg_csum(data_src,
                                                                   blksize);
                                        else
                                                sum = lpfc_bg_crc(data_src,
                                                                  blksize);
                                        if ((guard_tag != sum)) {
                                                err_type = BGS_GUARD_ERR_MASK;
                                                goto out;
                                        }
                                }

                                /* Reference Tag checking */
                                ref_tag = be32_to_cpu(src->ref_tag);
                                if (chk_ref && (ref_tag != start_ref_tag)) {
                                        err_type = BGS_REFTAG_ERR_MASK;
                                        goto out;
                                }
                                start_ref_tag++;

                                /* App Tag checking */
                                app_tag = src->app_tag;
                                if (chk_app && (app_tag != start_app_tag)) {
                                        err_type = BGS_APPTAG_ERR_MASK;
                                        goto out;
                                }
skipit:
                                len -= sizeof(struct scsi_dif_tuple);
                                if (len < 0)
                                        len = 0;
                                src++;

                                data_src += blksize;
                                data_len -= blksize;

                                /*

                                 * Are we at the end of the Data segment?
                                 * The data segment is only used for Guard
                                 * tag checking.
                                 */
                                if (chk_guard && (data_len == 0)) {
                                        chk_guard = 0;
                                        sgde = sg_next(sgde);
                                        if (!sgde)
                                                goto out;

                                        data_src = (uint8_t *)sg_virt(sgde);
                                        data_len = sgde->length;
                                        if ((data_len & (blksize - 1)) == 0)
                                                chk_guard = 1;
                                }
                        }

                        /* Goto the next Protection data segment */
                        sgpe = sg_next(sgpe);
                        if (sgpe) {
                                src = (struct scsi_dif_tuple *)sg_virt(sgpe);
                                len = sgpe->length;
                        } else {
                                src = NULL;
                        }
                        protsegcnt--;
                }
        }
out:
        if (err_type == BGS_GUARD_ERR_MASK) {
                scsi_build_sense_buffer(1, cmd->sense_buffer, ILLEGAL_REQUEST,
                                        0x10, 0x1);
                cmd->result = DRIVER_SENSE << 24 | DID_ABORT << 16 |
                              SAM_STAT_CHECK_CONDITION;
                phba->bg_guard_err_cnt++;
                lpfc_printf_log(phba, KERN_WARNING, LOG_FCP | LOG_BG,
                                "9069 BLKGRD: LBA %lx grd_tag error %x != %x\n",
                                (unsigned long)scsi_get_lba(cmd),
                                sum, guard_tag);

        } else if (err_type == BGS_REFTAG_ERR_MASK) {
                scsi_build_sense_buffer(1, cmd->sense_buffer, ILLEGAL_REQUEST,
                                        0x10, 0x3);
                cmd->result = DRIVER_SENSE << 24 | DID_ABORT << 16 |
                              SAM_STAT_CHECK_CONDITION;

                phba->bg_reftag_err_cnt++;
                lpfc_printf_log(phba, KERN_WARNING, LOG_FCP | LOG_BG,
                                "9066 BLKGRD: LBA %lx ref_tag error %x != %x\n",
                                (unsigned long)scsi_get_lba(cmd),
                                ref_tag, start_ref_tag);

        } else if (err_type == BGS_APPTAG_ERR_MASK) {
                scsi_build_sense_buffer(1, cmd->sense_buffer, ILLEGAL_REQUEST,
                                        0x10, 0x2);
                cmd->result = DRIVER_SENSE << 24 | DID_ABORT << 16 |
                              SAM_STAT_CHECK_CONDITION;

                phba->bg_apptag_err_cnt++;
                lpfc_printf_log(phba, KERN_WARNING, LOG_FCP | LOG_BG,
                                "9041 BLKGRD: LBA %lx app_tag error %x != %x\n",
                                (unsigned long)scsi_get_lba(cmd),
                                app_tag, start_app_tag);
        }
}


/*
 * This function checks for BlockGuard errors detected by
 * the HBA.  In case of errors, the ASC/ASCQ fields in the
 * sense buffer will be set accordingly, paired with
 * ILLEGAL_REQUEST to signal to the kernel that the HBA
 * detected corruption.
 *
 * Returns:
 *  0 - No error found
 *  1 - BlockGuard error found
 * -1 - Internal error (bad profile, ...etc)
 */
static int
lpfc_parse_bg_err(struct lpfc_hba *phba, struct lpfc_scsi_buf *lpfc_cmd,
                        struct lpfc_iocbq *pIocbOut)
{
        struct scsi_cmnd *cmd = lpfc_cmd->pCmd;
        struct sli3_bg_fields *bgf = &pIocbOut->iocb.unsli3.sli3_bg;
        int ret = 0;
        uint32_t bghm = bgf->bghm;
        uint32_t bgstat = bgf->bgstat;
        uint64_t failing_sector = 0;

        spin_lock(&_dump_buf_lock);
        if (!_dump_buf_done) {
                lpfc_printf_log(phba, KERN_ERR, LOG_BG,  "9070 BLKGRD: Saving"
                        " Data for %u blocks to debugfs\n",
                                (cmd->cmnd[7] << 8 | cmd->cmnd[8]));
                lpfc_debug_save_data(phba, cmd);

                /* If we have a prot sgl, save the DIF buffer */
                if (lpfc_prot_group_type(phba, cmd) ==
                                LPFC_PG_TYPE_DIF_BUF) {
                        lpfc_printf_log(phba, KERN_ERR, LOG_BG, "9071 BLKGRD: "
                                "Saving DIF for %u blocks to debugfs\n",
                                (cmd->cmnd[7] << 8 | cmd->cmnd[8]));
                        lpfc_debug_save_dif(phba, cmd);
                }

                _dump_buf_done = 1;
        }
        spin_unlock(&_dump_buf_lock);

        if (lpfc_bgs_get_invalid_prof(bgstat)) {
                cmd->result = DID_ERROR << 16;
                lpfc_printf_log(phba, KERN_WARNING, LOG_FCP | LOG_BG,
                                "9072 BLKGRD: Invalid BG Profile in cmd"
                                " 0x%x lba 0x%llx blk cnt 0x%x "
                                "bgstat=x%x bghm=x%x\n", cmd->cmnd[0],
                                (unsigned long long)scsi_get_lba(cmd),
                                blk_rq_sectors(cmd->request), bgstat, bghm);
                ret = (-1);
                goto out;
        }

        if (lpfc_bgs_get_uninit_dif_block(bgstat)) {
                cmd->result = DID_ERROR << 16;
                lpfc_printf_log(phba, KERN_WARNING, LOG_FCP | LOG_BG,
                                "9073 BLKGRD: Invalid BG PDIF Block in cmd"
                                " 0x%x lba 0x%llx blk cnt 0x%x "
                                "bgstat=x%x bghm=x%x\n", cmd->cmnd[0],
                                (unsigned long long)scsi_get_lba(cmd),
                                blk_rq_sectors(cmd->request), bgstat, bghm);
                ret = (-1);
                goto out;
        }

        if (lpfc_bgs_get_guard_err(bgstat)) {
                ret = 1;

                scsi_build_sense_buffer(1, cmd->sense_buffer, ILLEGAL_REQUEST,
                                0x10, 0x1);
                cmd->result = DRIVER_SENSE << 24 | DID_ABORT << 16 |
                              SAM_STAT_CHECK_CONDITION;
                phba->bg_guard_err_cnt++;
                lpfc_printf_log(phba, KERN_WARNING, LOG_FCP | LOG_BG,
                                "9055 BLKGRD: Guard Tag error in cmd"
                                " 0x%x lba 0x%llx blk cnt 0x%x "
                                "bgstat=x%x bghm=x%x\n", cmd->cmnd[0],
                                (unsigned long long)scsi_get_lba(cmd),
                                blk_rq_sectors(cmd->request), bgstat, bghm);
        }

        if (lpfc_bgs_get_reftag_err(bgstat)) {
                ret = 1;

                scsi_build_sense_buffer(1, cmd->sense_buffer, ILLEGAL_REQUEST,
                                0x10, 0x3);
                cmd->result = DRIVER_SENSE << 24 | DID_ABORT << 16 |
                              SAM_STAT_CHECK_CONDITION;

                phba->bg_reftag_err_cnt++;
                lpfc_printf_log(phba, KERN_WARNING, LOG_FCP | LOG_BG,
                                "9056 BLKGRD: Ref Tag error in cmd"
                                " 0x%x lba 0x%llx blk cnt 0x%x "
                                "bgstat=x%x bghm=x%x\n", cmd->cmnd[0],
                                (unsigned long long)scsi_get_lba(cmd),
                                blk_rq_sectors(cmd->request), bgstat, bghm);
        }

        if (lpfc_bgs_get_apptag_err(bgstat)) {
                ret = 1;

                scsi_build_sense_buffer(1, cmd->sense_buffer, ILLEGAL_REQUEST,
                                0x10, 0x2);
                cmd->result = DRIVER_SENSE << 24 | DID_ABORT << 16 |
                              SAM_STAT_CHECK_CONDITION;

                phba->bg_apptag_err_cnt++;
                lpfc_printf_log(phba, KERN_WARNING, LOG_FCP | LOG_BG,
                                "9061 BLKGRD: App Tag error in cmd"
                                " 0x%x lba 0x%llx blk cnt 0x%x "
                                "bgstat=x%x bghm=x%x\n", cmd->cmnd[0],
                                (unsigned long long)scsi_get_lba(cmd),
                                blk_rq_sectors(cmd->request), bgstat, bghm);
        }

        if (lpfc_bgs_get_hi_water_mark_present(bgstat)) {
                /*
                 * setup sense data descriptor 0 per SPC-4 as an information
                 * field, and put the failing LBA in it.
                 * This code assumes there was also a guard/app/ref tag error
                 * indication.
                 */
                cmd->sense_buffer[7] = 0xc;   /* Additional sense length */
                cmd->sense_buffer[8] = 0;     /* Information descriptor type */
                cmd->sense_buffer[9] = 0xa;   /* Additional descriptor length */
                cmd->sense_buffer[10] = 0x80; /* Validity bit */

                /* bghm is a "on the wire" FC frame based count */
                switch (scsi_get_prot_op(cmd)) {
                case SCSI_PROT_READ_INSERT:
                case SCSI_PROT_WRITE_STRIP:
                        bghm /= cmd->device->sector_size;
                        break;
                case SCSI_PROT_READ_STRIP:
                case SCSI_PROT_WRITE_INSERT:
                case SCSI_PROT_READ_PASS:
                case SCSI_PROT_WRITE_PASS:
                        bghm /= (cmd->device->sector_size +
                                sizeof(struct scsi_dif_tuple));
                        break;
                }

                failing_sector = scsi_get_lba(cmd);
                failing_sector += bghm;

                /* Descriptor Information */
                put_unaligned_be64(failing_sector, &cmd->sense_buffer[12]);
        }

        if (!ret) {
                /* No error was reported - problem in FW? */
                lpfc_printf_log(phba, KERN_WARNING, LOG_FCP | LOG_BG,
                                "9057 BLKGRD: Unknown error in cmd"
                                " 0x%x lba 0x%llx blk cnt 0x%x "
                                "bgstat=x%x bghm=x%x\n", cmd->cmnd[0],
                                (unsigned long long)scsi_get_lba(cmd),
                                blk_rq_sectors(cmd->request), bgstat, bghm);

                /* Calcuate what type of error it was */
                lpfc_calc_bg_err(phba, lpfc_cmd);
        }
out:
        return ret;
}

/**
 * lpfc_scsi_prep_dma_buf_s4 - DMA mapping for scsi buffer to SLI4 IF spec
 * @phba: The Hba for which this call is being executed.
 * @lpfc_cmd: The scsi buffer which is going to be mapped.
 *
 * This routine does the pci dma mapping for scatter-gather list of scsi cmnd
 * field of @lpfc_cmd for device with SLI-4 interface spec.
 *
 * Return codes:
 *      1 - Error
 *      0 - Success
 **/
static int
lpfc_scsi_prep_dma_buf_s4(struct lpfc_hba *phba, struct lpfc_scsi_buf *lpfc_cmd)
{
        struct scsi_cmnd *scsi_cmnd = lpfc_cmd->pCmd;
        struct scatterlist *sgel = NULL;
        struct fcp_cmnd *fcp_cmnd = lpfc_cmd->fcp_cmnd;
        struct sli4_sge *sgl = (struct sli4_sge *)lpfc_cmd->fcp_bpl;
        struct sli4_sge *first_data_sgl;
        IOCB_t *iocb_cmd = &lpfc_cmd->cur_iocbq.iocb;
        dma_addr_t physaddr;
        uint32_t num_bde = 0;
        uint32_t dma_len;
        uint32_t dma_offset = 0;
        int nseg;
        struct ulp_bde64 *bde;

        /*
         * There are three possibilities here - use scatter-gather segment, use
         * the single mapping, or neither.  Start the lpfc command prep by
         * bumping the bpl beyond the fcp_cmnd and fcp_rsp regions to the first
         * data bde entry.
         */
        if (scsi_sg_count(scsi_cmnd)) {
                /*
                 * The driver stores the segment count returned from pci_map_sg
                 * because this a count of dma-mappings used to map the use_sg
                 * pages.  They are not guaranteed to be the same for those
                 * architectures that implement an IOMMU.
                 */

                nseg = scsi_dma_map(scsi_cmnd);
                if (unlikely(nseg <= 0))
                        return 1;
                sgl += 1;
                /* clear the last flag in the fcp_rsp map entry */
                sgl->word2 = le32_to_cpu(sgl->word2);
                bf_set(lpfc_sli4_sge_last, sgl, 0);
                sgl->word2 = cpu_to_le32(sgl->word2);
                sgl += 1;
                first_data_sgl = sgl;
                lpfc_cmd->seg_cnt = nseg;
                if (lpfc_cmd->seg_cnt > phba->cfg_sg_seg_cnt) {
                        lpfc_printf_log(phba, KERN_ERR, LOG_BG, "9074 BLKGRD:"
                                " %s: Too many sg segments from "
                                "dma_map_sg.  Config %d, seg_cnt %d\n",
                                __func__, phba->cfg_sg_seg_cnt,
                               lpfc_cmd->seg_cnt);
                        lpfc_cmd->seg_cnt = 0;
                        scsi_dma_unmap(scsi_cmnd);
                        return 1;
                }

                /*
                 * The driver established a maximum scatter-gather segment count
                 * during probe that limits the number of sg elements in any
                 * single scsi command.  Just run through the seg_cnt and format
                 * the sge's.
                 * When using SLI-3 the driver will try to fit all the BDEs into
                 * the IOCB. If it can't then the BDEs get added to a BPL as it
                 * does for SLI-2 mode.
                 */
                scsi_for_each_sg(scsi_cmnd, sgel, nseg, num_bde) {
                        physaddr = sg_dma_address(sgel);
                        dma_len = sg_dma_len(sgel);
                        sgl->addr_lo = cpu_to_le32(putPaddrLow(physaddr));
                        sgl->addr_hi = cpu_to_le32(putPaddrHigh(physaddr));
                        sgl->word2 = le32_to_cpu(sgl->word2);
                        if ((num_bde + 1) == nseg)
                                bf_set(lpfc_sli4_sge_last, sgl, 1);
                        else
                                bf_set(lpfc_sli4_sge_last, sgl, 0);
                        bf_set(lpfc_sli4_sge_offset, sgl, dma_offset);
                        bf_set(lpfc_sli4_sge_type, sgl, LPFC_SGE_TYPE_DATA);
                        sgl->word2 = cpu_to_le32(sgl->word2);
                        sgl->sge_len = cpu_to_le32(dma_len);
                        dma_offset += dma_len;
                        sgl++;
                }
                /*
                 * Setup the first Payload BDE. For FCoE we just key off
                 * Performance Hints, for FC we use lpfc_enable_pbde.
                 * We populate words 13-15 of IOCB/WQE.
                 */
                if ((phba->sli3_options & LPFC_SLI4_PERFH_ENABLED) ||
                    phba->cfg_enable_pbde) {
                        bde = (struct ulp_bde64 *)
                                &(iocb_cmd->unsli3.sli3Words[5]);
                        bde->addrLow = first_data_sgl->addr_lo;
                        bde->addrHigh = first_data_sgl->addr_hi;
                        bde->tus.f.bdeSize =
                                        le32_to_cpu(first_data_sgl->sge_len);
                        bde->tus.f.bdeFlags = BUFF_TYPE_BDE_64;
                        bde->tus.w = cpu_to_le32(bde->tus.w);
                }
        } else {
                sgl += 1;
                /* clear the last flag in the fcp_rsp map entry */
                sgl->word2 = le32_to_cpu(sgl->word2);
                bf_set(lpfc_sli4_sge_last, sgl, 1);
                sgl->word2 = cpu_to_le32(sgl->word2);

                if ((phba->sli3_options & LPFC_SLI4_PERFH_ENABLED) ||
                    phba->cfg_enable_pbde) {
                        bde = (struct ulp_bde64 *)
                                &(iocb_cmd->unsli3.sli3Words[5]);
                        memset(bde, 0, (sizeof(uint32_t) * 3));
                }
        }

        /*
         * Finish initializing those IOCB fields that are dependent on the
         * scsi_cmnd request_buffer.  Note that for SLI-2 the bdeSize is
         * explicitly reinitialized.
         * all iocb memory resources are reused.
         */
        fcp_cmnd->fcpDl = cpu_to_be32(scsi_bufflen(scsi_cmnd));

        /*
         * Due to difference in data length between DIF/non-DIF paths,
         * we need to set word 4 of IOCB here
         */
        iocb_cmd->un.fcpi.fcpi_parm = scsi_bufflen(scsi_cmnd);

        /*
         * If the OAS driver feature is enabled and the lun is enabled for
         * OAS, set the oas iocb related flags.
         */
        if ((phba->cfg_fof) && ((struct lpfc_device_data *)
                scsi_cmnd->device->hostdata)->oas_enabled) {
                lpfc_cmd->cur_iocbq.iocb_flag |= (LPFC_IO_OAS | LPFC_IO_FOF);
                lpfc_cmd->cur_iocbq.priority = ((struct lpfc_device_data *)
                        scsi_cmnd->device->hostdata)->priority;
        }
        return 0;
}

/**
 * lpfc_bg_scsi_prep_dma_buf_s4 - DMA mapping for scsi buffer to SLI4 IF spec
 * @phba: The Hba for which this call is being executed.
 * @lpfc_cmd: The scsi buffer which is going to be mapped.
 *
 * This is the protection/DIF aware version of
 * lpfc_scsi_prep_dma_buf(). It may be a good idea to combine the
 * two functions eventually, but for now, it's here
 **/
static int
lpfc_bg_scsi_prep_dma_buf_s4(struct lpfc_hba *phba,
                struct lpfc_scsi_buf *lpfc_cmd)
{
        struct scsi_cmnd *scsi_cmnd = lpfc_cmd->pCmd;
        struct fcp_cmnd *fcp_cmnd = lpfc_cmd->fcp_cmnd;
        struct sli4_sge *sgl = (struct sli4_sge *)(lpfc_cmd->fcp_bpl);
        IOCB_t *iocb_cmd = &lpfc_cmd->cur_iocbq.iocb;
        uint32_t num_sge = 0;
        int datasegcnt, protsegcnt, datadir = scsi_cmnd->sc_data_direction;
        int prot_group_type = 0;
        int fcpdl;

        /*
         * Start the lpfc command prep by bumping the sgl beyond fcp_cmnd
         *  fcp_rsp regions to the first data sge entry
         */
        if (scsi_sg_count(scsi_cmnd)) {
                /*
                 * The driver stores the segment count returned from pci_map_sg
                 * because this a count of dma-mappings used to map the use_sg
                 * pages.  They are not guaranteed to be the same for those
                 * architectures that implement an IOMMU.
                 */
                datasegcnt = dma_map_sg(&phba->pcidev->dev,
                                        scsi_sglist(scsi_cmnd),
                                        scsi_sg_count(scsi_cmnd), datadir);
                if (unlikely(!datasegcnt))
                        return 1;

                sgl += 1;
                /* clear the last flag in the fcp_rsp map entry */
                sgl->word2 = le32_to_cpu(sgl->word2);
                bf_set(lpfc_sli4_sge_last, sgl, 0);
                sgl->word2 = cpu_to_le32(sgl->word2);

                sgl += 1;
                lpfc_cmd->seg_cnt = datasegcnt;

                /* First check if data segment count from SCSI Layer is good */
                if (lpfc_cmd->seg_cnt > phba->cfg_sg_seg_cnt)
                        goto err;

                prot_group_type = lpfc_prot_group_type(phba, scsi_cmnd);

                switch (prot_group_type) {
                case LPFC_PG_TYPE_NO_DIF:
                        /* Here we need to add a DISEED to the count */
                        if ((lpfc_cmd->seg_cnt + 1) > phba->cfg_total_seg_cnt)
                                goto err;

                        num_sge = lpfc_bg_setup_sgl(phba, scsi_cmnd, sgl,
                                        datasegcnt);

                        /* we should have 2 or more entries in buffer list */
                        if (num_sge < 2)
                                goto err;
                        break;

                case LPFC_PG_TYPE_DIF_BUF:
                        /*
                         * This type indicates that protection buffers are
                         * passed to the driver, so that needs to be prepared
                         * for DMA
                         */
                        protsegcnt = dma_map_sg(&phba->pcidev->dev,
                                        scsi_prot_sglist(scsi_cmnd),
                                        scsi_prot_sg_count(scsi_cmnd), datadir);
                        if (unlikely(!protsegcnt)) {
                                scsi_dma_unmap(scsi_cmnd);
                                return 1;
                        }

                        lpfc_cmd->prot_seg_cnt = protsegcnt;
                        /*
                         * There is a minimun of 3 SGEs used for every
                         * protection data segment.
                         */
                        if ((lpfc_cmd->prot_seg_cnt * 3) >
                            (phba->cfg_total_seg_cnt - 2))
                                goto err;

                        num_sge = lpfc_bg_setup_sgl_prot(phba, scsi_cmnd, sgl,
                                        datasegcnt, protsegcnt);

                        /* we should have 3 or more entries in buffer list */
                        if ((num_sge < 3) ||
                            (num_sge > phba->cfg_total_seg_cnt))
                                goto err;
                        break;

                case LPFC_PG_TYPE_INVALID:
                default:
                        scsi_dma_unmap(scsi_cmnd);
                        lpfc_cmd->seg_cnt = 0;

                        lpfc_printf_log(phba, KERN_ERR, LOG_FCP,
                                        "9083 Unexpected protection group %i\n",
                                        prot_group_type);
                        return 1;
                }
        }

        switch (scsi_get_prot_op(scsi_cmnd)) {
        case SCSI_PROT_WRITE_STRIP:
        case SCSI_PROT_READ_STRIP:
                lpfc_cmd->cur_iocbq.iocb_flag |= LPFC_IO_DIF_STRIP;
                break;
        case SCSI_PROT_WRITE_INSERT:
        case SCSI_PROT_READ_INSERT:
                lpfc_cmd->cur_iocbq.iocb_flag |= LPFC_IO_DIF_INSERT;
                break;
        case SCSI_PROT_WRITE_PASS:
        case SCSI_PROT_READ_PASS:
                lpfc_cmd->cur_iocbq.iocb_flag |= LPFC_IO_DIF_PASS;
                break;
        }

        fcpdl = lpfc_bg_scsi_adjust_dl(phba, lpfc_cmd);
        fcp_cmnd->fcpDl = be32_to_cpu(fcpdl);

        /*
         * Due to difference in data length between DIF/non-DIF paths,
         * we need to set word 4 of IOCB here
         */
        iocb_cmd->un.fcpi.fcpi_parm = fcpdl;

        /*
         * If the OAS driver feature is enabled and the lun is enabled for
         * OAS, set the oas iocb related flags.
         */
        if ((phba->cfg_fof) && ((struct lpfc_device_data *)
                scsi_cmnd->device->hostdata)->oas_enabled)
                lpfc_cmd->cur_iocbq.iocb_flag |= (LPFC_IO_OAS | LPFC_IO_FOF);

        return 0;
err:
        if (lpfc_cmd->seg_cnt)
                scsi_dma_unmap(scsi_cmnd);
        if (lpfc_cmd->prot_seg_cnt)
                dma_unmap_sg(&phba->pcidev->dev, scsi_prot_sglist(scsi_cmnd),
                             scsi_prot_sg_count(scsi_cmnd),
                             scsi_cmnd->sc_data_direction);

        lpfc_printf_log(phba, KERN_ERR, LOG_FCP,
                        "9084 Cannot setup S/G List for HBA"
                        "IO segs %d/%d SGL %d SCSI %d: %d %d\n",
                        lpfc_cmd->seg_cnt, lpfc_cmd->prot_seg_cnt,
                        phba->cfg_total_seg_cnt, phba->cfg_sg_seg_cnt,
                        prot_group_type, num_sge);

        lpfc_cmd->seg_cnt = 0;
        lpfc_cmd->prot_seg_cnt = 0;
        return 1;
}

/**
 * lpfc_scsi_prep_dma_buf - Wrapper function for DMA mapping of scsi buffer
 * @phba: The Hba for which this call is being executed.
 * @lpfc_cmd: The scsi buffer which is going to be mapped.
 *
 * This routine wraps the actual DMA mapping function pointer from the
 * lpfc_hba struct.
 *
 * Return codes:
 *      1 - Error
 *      0 - Success
 **/
static inline int
lpfc_scsi_prep_dma_buf(struct lpfc_hba *phba, struct lpfc_scsi_buf *lpfc_cmd)
{
        return phba->lpfc_scsi_prep_dma_buf(phba, lpfc_cmd);
}

/**
 * lpfc_bg_scsi_prep_dma_buf - Wrapper function for DMA mapping of scsi buffer
 * using BlockGuard.
 * @phba: The Hba for which this call is being executed.
 * @lpfc_cmd: The scsi buffer which is going to be mapped.
 *
 * This routine wraps the actual DMA mapping function pointer from the
 * lpfc_hba struct.
 *
 * Return codes:
 *      1 - Error
 *      0 - Success
 **/
static inline int
lpfc_bg_scsi_prep_dma_buf(struct lpfc_hba *phba, struct lpfc_scsi_buf *lpfc_cmd)
{
        return phba->lpfc_bg_scsi_prep_dma_buf(phba, lpfc_cmd);
}

/**
 * lpfc_send_scsi_error_event - Posts an event when there is SCSI error
 * @phba: Pointer to hba context object.
 * @vport: Pointer to vport object.
 * @lpfc_cmd: Pointer to lpfc scsi command which reported the error.
 * @rsp_iocb: Pointer to response iocb object which reported error.
 *
 * This function posts an event when there is a SCSI command reporting
 * error from the scsi device.
 **/
static void
lpfc_send_scsi_error_event(struct lpfc_hba *phba, struct lpfc_vport *vport,
                struct lpfc_scsi_buf *lpfc_cmd, struct lpfc_iocbq *rsp_iocb) {
        struct scsi_cmnd *cmnd = lpfc_cmd->pCmd;
        struct fcp_rsp *fcprsp = lpfc_cmd->fcp_rsp;
        uint32_t resp_info = fcprsp->rspStatus2;
        uint32_t scsi_status = fcprsp->rspStatus3;
        uint32_t fcpi_parm = rsp_iocb->iocb.un.fcpi.fcpi_parm;
        struct lpfc_fast_path_event *fast_path_evt = NULL;
        struct lpfc_nodelist *pnode = lpfc_cmd->rdata->pnode;
        unsigned long flags;

        if (!pnode || !NLP_CHK_NODE_ACT(pnode))
                return;

        /* If there is queuefull or busy condition send a scsi event */
        if ((cmnd->result == SAM_STAT_TASK_SET_FULL) ||
                (cmnd->result == SAM_STAT_BUSY)) {
                fast_path_evt = lpfc_alloc_fast_evt(phba);
                if (!fast_path_evt)
                        return;
                fast_path_evt->un.scsi_evt.event_type =
                        FC_REG_SCSI_EVENT;
                fast_path_evt->un.scsi_evt.subcategory =
                (cmnd->result == SAM_STAT_TASK_SET_FULL) ?
                LPFC_EVENT_QFULL : LPFC_EVENT_DEVBSY;
                fast_path_evt->un.scsi_evt.lun = cmnd->device->lun;
                memcpy(&fast_path_evt->un.scsi_evt.wwpn,
                        &pnode->nlp_portname, sizeof(struct lpfc_name));
                memcpy(&fast_path_evt->un.scsi_evt.wwnn,
                        &pnode->nlp_nodename, sizeof(struct lpfc_name));
        } else if ((resp_info & SNS_LEN_VALID) && fcprsp->rspSnsLen &&
                ((cmnd->cmnd[0] == READ_10) || (cmnd->cmnd[0] == WRITE_10))) {
                fast_path_evt = lpfc_alloc_fast_evt(phba);
                if (!fast_path_evt)
                        return;
                fast_path_evt->un.check_cond_evt.scsi_event.event_type =
                        FC_REG_SCSI_EVENT;
                fast_path_evt->un.check_cond_evt.scsi_event.subcategory =
                        LPFC_EVENT_CHECK_COND;
                fast_path_evt->un.check_cond_evt.scsi_event.lun =
                        cmnd->device->lun;
                memcpy(&fast_path_evt->un.check_cond_evt.scsi_event.wwpn,
                        &pnode->nlp_portname, sizeof(struct lpfc_name));
                memcpy(&fast_path_evt->un.check_cond_evt.scsi_event.wwnn,
                        &pnode->nlp_nodename, sizeof(struct lpfc_name));
                fast_path_evt->un.check_cond_evt.sense_key =
                        cmnd->sense_buffer[2] & 0xf;
                fast_path_evt->un.check_cond_evt.asc = cmnd->sense_buffer[12];
                fast_path_evt->un.check_cond_evt.ascq = cmnd->sense_buffer[13];
        } else if ((cmnd->sc_data_direction == DMA_FROM_DEVICE) &&
                     fcpi_parm &&
                     ((be32_to_cpu(fcprsp->rspResId) != fcpi_parm) ||
                        ((scsi_status == SAM_STAT_GOOD) &&
                        !(resp_info & (RESID_UNDER | RESID_OVER))))) {
                /*
                 * If status is good or resid does not match with fcp_param and
                 * there is valid fcpi_parm, then there is a read_check error
                 */
                fast_path_evt = lpfc_alloc_fast_evt(phba);
                if (!fast_path_evt)
                        return;
                fast_path_evt->un.read_check_error.header.event_type =
                        FC_REG_FABRIC_EVENT;
                fast_path_evt->un.read_check_error.header.subcategory =
                        LPFC_EVENT_FCPRDCHKERR;
                memcpy(&fast_path_evt->un.read_check_error.header.wwpn,
                        &pnode->nlp_portname, sizeof(struct lpfc_name));
                memcpy(&fast_path_evt->un.read_check_error.header.wwnn,
                        &pnode->nlp_nodename, sizeof(struct lpfc_name));
                fast_path_evt->un.read_check_error.lun = cmnd->device->lun;
                fast_path_evt->un.read_check_error.opcode = cmnd->cmnd[0];
                fast_path_evt->un.read_check_error.fcpiparam =
                        fcpi_parm;
        } else
                return;

        fast_path_evt->vport = vport;
        spin_lock_irqsave(&phba->hbalock, flags);
        list_add_tail(&fast_path_evt->work_evt.evt_listp, &phba->work_list);
        spin_unlock_irqrestore(&phba->hbalock, flags);
        lpfc_worker_wake_up(phba);
        return;
}

/**
 * lpfc_scsi_unprep_dma_buf - Un-map DMA mapping of SG-list for dev
 * @phba: The HBA for which this call is being executed.
 * @psb: The scsi buffer which is going to be un-mapped.
 *
 * This routine does DMA un-mapping of scatter gather list of scsi command
 * field of @lpfc_cmd for device with SLI-3 interface spec.
 **/
static void
lpfc_scsi_unprep_dma_buf(struct lpfc_hba *phba, struct lpfc_scsi_buf *psb)
{
        /*
         * There are only two special cases to consider.  (1) the scsi command
         * requested scatter-gather usage or (2) the scsi command allocated
         * a request buffer, but did not request use_sg.  There is a third
         * case, but it does not require resource deallocation.
         */
        if (psb->seg_cnt > 0)
                scsi_dma_unmap(psb->pCmd);
        if (psb->prot_seg_cnt > 0)
                dma_unmap_sg(&phba->pcidev->dev, scsi_prot_sglist(psb->pCmd),
                                scsi_prot_sg_count(psb->pCmd),
                                psb->pCmd->sc_data_direction);
}

/**
 * lpfc_handler_fcp_err - FCP response handler
 * @vport: The virtual port for which this call is being executed.
 * @lpfc_cmd: Pointer to lpfc_scsi_buf data structure.
 * @rsp_iocb: The response IOCB which contains FCP error.
 *
 * This routine is called to process response IOCB with status field
 * IOSTAT_FCP_RSP_ERROR. This routine sets result field of scsi command
 * based upon SCSI and FCP error.
 **/
static void
lpfc_handle_fcp_err(struct lpfc_vport *vport, struct lpfc_scsi_buf *lpfc_cmd,
                    struct lpfc_iocbq *rsp_iocb)
{
        struct lpfc_hba *phba = vport->phba;
        struct scsi_cmnd *cmnd = lpfc_cmd->pCmd;
        struct fcp_cmnd *fcpcmd = lpfc_cmd->fcp_cmnd;
        struct fcp_rsp *fcprsp = lpfc_cmd->fcp_rsp;
        uint32_t fcpi_parm = rsp_iocb->iocb.un.fcpi.fcpi_parm;
        uint32_t resp_info = fcprsp->rspStatus2;
        uint32_t scsi_status = fcprsp->rspStatus3;
        uint32_t *lp;
        uint32_t host_status = DID_OK;
        uint32_t rsplen = 0;
        uint32_t fcpDl;
        uint32_t logit = LOG_FCP | LOG_FCP_ERROR;


        /*
         *  If this is a task management command, there is no
         *  scsi packet associated with this lpfc_cmd.  The driver
         *  consumes it.
         */
        if (fcpcmd->fcpCntl2) {
                scsi_status = 0;
                goto out;
        }

        if (resp_info & RSP_LEN_VALID) {
                rsplen = be32_to_cpu(fcprsp->rspRspLen);
                if (rsplen != 0 && rsplen != 4 && rsplen != 8) {
                        lpfc_printf_vlog(vport, KERN_ERR, LOG_FCP,
                                 "2719 Invalid response length: "
                                 "tgt x%x lun x%llx cmnd x%x rsplen x%x\n",
                                 cmnd->device->id,
                                 cmnd->device->lun, cmnd->cmnd[0],
                                 rsplen);
                        host_status = DID_ERROR;
                        goto out;
                }
                if (fcprsp->rspInfo3 != RSP_NO_FAILURE) {
                        lpfc_printf_vlog(vport, KERN_ERR, LOG_FCP,
                                 "2757 Protocol failure detected during "
                                 "processing of FCP I/O op: "
                                 "tgt x%x lun x%llx cmnd x%x rspInfo3 x%x\n",
                                 cmnd->device->id,
                                 cmnd->device->lun, cmnd->cmnd[0],
                                 fcprsp->rspInfo3);
                        host_status = DID_ERROR;
                        goto out;
                }
        }

        if ((resp_info & SNS_LEN_VALID) && fcprsp->rspSnsLen) {
                uint32_t snslen = be32_to_cpu(fcprsp->rspSnsLen);
                if (snslen > SCSI_SENSE_BUFFERSIZE)
                        snslen = SCSI_SENSE_BUFFERSIZE;

                if (resp_info & RSP_LEN_VALID)
                  rsplen = be32_to_cpu(fcprsp->rspRspLen);
                memcpy(cmnd->sense_buffer, &fcprsp->rspInfo0 + rsplen, snslen);
        }
        lp = (uint32_t *)cmnd->sense_buffer;

        /* special handling for under run conditions */
        if (!scsi_status && (resp_info & RESID_UNDER)) {
                /* don't log under runs if fcp set... */
                if (vport->cfg_log_verbose & LOG_FCP)
                        logit = LOG_FCP_ERROR;
                /* unless operator says so */
                if (vport->cfg_log_verbose & LOG_FCP_UNDER)
                        logit = LOG_FCP_UNDER;
        }

        lpfc_printf_vlog(vport, KERN_WARNING, logit,
                         "9024 FCP command x%x failed: x%x SNS x%x x%x "
                         "Data: x%x x%x x%x x%x x%x\n",
                         cmnd->cmnd[0], scsi_status,
                         be32_to_cpu(*lp), be32_to_cpu(*(lp + 3)), resp_info,
                         be32_to_cpu(fcprsp->rspResId),
                         be32_to_cpu(fcprsp->rspSnsLen),
                         be32_to_cpu(fcprsp->rspRspLen),
                         fcprsp->rspInfo3);

        scsi_set_resid(cmnd, 0);
        fcpDl = be32_to_cpu(fcpcmd->fcpDl);
        if (resp_info & RESID_UNDER) {
                scsi_set_resid(cmnd, be32_to_cpu(fcprsp->rspResId));

                lpfc_printf_vlog(vport, KERN_INFO, LOG_FCP_UNDER,
                                 "9025 FCP Underrun, expected %d, "
                                 "residual %d Data: x%x x%x x%x\n",
                                 fcpDl,
                                 scsi_get_resid(cmnd), fcpi_parm, cmnd->cmnd[0],
                                 cmnd->underflow);

                /*
                 * If there is an under run, check if under run reported by
                 * storage array is same as the under run reported by HBA.
                 * If this is not same, there is a dropped frame.
                 */
                if (fcpi_parm && (scsi_get_resid(cmnd) != fcpi_parm)) {
                        lpfc_printf_vlog(vport, KERN_WARNING,
                                         LOG_FCP | LOG_FCP_ERROR,
                                         "9026 FCP Read Check Error "
                                         "and Underrun Data: x%x x%x x%x x%x\n",
                                         fcpDl,
                                         scsi_get_resid(cmnd), fcpi_parm,
                                         cmnd->cmnd[0]);
                        scsi_set_resid(cmnd, scsi_bufflen(cmnd));
                        host_status = DID_ERROR;
                }
                /*
                 * The cmnd->underflow is the minimum number of bytes that must
                 * be transferred for this command.  Provided a sense condition
                 * is not present, make sure the actual amount transferred is at
                 * least the underflow value or fail.
                 */
                if (!(resp_info & SNS_LEN_VALID) &&
                    (scsi_status == SAM_STAT_GOOD) &&
                    (scsi_bufflen(cmnd) - scsi_get_resid(cmnd)
                     < cmnd->underflow)) {
                        lpfc_printf_vlog(vport, KERN_INFO, LOG_FCP,
                                         "9027 FCP command x%x residual "
                                         "underrun converted to error "
                                         "Data: x%x x%x x%x\n",
                                         cmnd->cmnd[0], scsi_bufflen(cmnd),
                                         scsi_get_resid(cmnd), cmnd->underflow);
                        host_status = DID_ERROR;
                }
        } else if (resp_info & RESID_OVER) {
                lpfc_printf_vlog(vport, KERN_WARNING, LOG_FCP,
                                 "9028 FCP command x%x residual overrun error. "
                                 "Data: x%x x%x\n", cmnd->cmnd[0],
                                 scsi_bufflen(cmnd), scsi_get_resid(cmnd));
                host_status = DID_ERROR;

        /*
         * Check SLI validation that all the transfer was actually done
         * (fcpi_parm should be zero). Apply check only to reads.
         */
        } else if (fcpi_parm) {
                lpfc_printf_vlog(vport, KERN_WARNING, LOG_FCP | LOG_FCP_ERROR,
                                 "9029 FCP %s Check Error xri x%x  Data: "
                                 "x%x x%x x%x x%x x%x\n",
                                 ((cmnd->sc_data_direction == DMA_FROM_DEVICE) ?
                                 "Read" : "Write"),
                                 ((phba->sli_rev == LPFC_SLI_REV4) ?
                                 lpfc_cmd->cur_iocbq.sli4_xritag :
                                 rsp_iocb->iocb.ulpContext),
                                 fcpDl, be32_to_cpu(fcprsp->rspResId),
                                 fcpi_parm, cmnd->cmnd[0], scsi_status);

                /* There is some issue with the LPe12000 that causes it
                 * to miscalculate the fcpi_parm and falsely trip this
                 * recovery logic.  Detect this case and don't error when true.
                 */
                if (fcpi_parm > fcpDl)
                        goto out;

                switch (scsi_status) {
                case SAM_STAT_GOOD:
                case SAM_STAT_CHECK_CONDITION:
                        /* Fabric dropped a data frame. Fail any successful
                         * command in which we detected dropped frames.
                         * A status of good or some check conditions could
                         * be considered a successful command.
                         */
                        host_status = DID_ERROR;
                        break;
                }
                scsi_set_resid(cmnd, scsi_bufflen(cmnd));
        }

 out:
        cmnd->result = host_status << 16 | scsi_status;
        lpfc_send_scsi_error_event(vport->phba, vport, lpfc_cmd, rsp_iocb);
}

/**
 * lpfc_sli4_scmd_to_wqidx_distr - scsi command to SLI4 WQ index distribution
 * @phba: Pointer to HBA context object.
 *
 * This routine performs a roundrobin SCSI command to SLI4 FCP WQ index
 * distribution.  This is called by __lpfc_sli_issue_iocb_s4() with the hbalock
 * held.
 * If scsi-mq is enabled, get the default block layer mapping of software queues
 * to hardware queues. This information is saved in request tag.
 *
 * Return: index into SLI4 fast-path FCP queue index.
 **/
int lpfc_sli4_scmd_to_wqidx_distr(struct lpfc_hba *phba,
                                  struct lpfc_scsi_buf *lpfc_cmd)
{
        struct scsi_cmnd *cmnd = lpfc_cmd->pCmd;
        struct lpfc_vector_map_info *cpup;
        int chann, cpu;
        uint32_t tag;
        uint16_t hwq;

        if (cmnd && shost_use_blk_mq(cmnd->device->host)) {
                tag = blk_mq_unique_tag(cmnd->request);
                hwq = blk_mq_unique_tag_to_hwq(tag);

                return hwq;
        }

        if (phba->cfg_fcp_io_sched == LPFC_FCP_SCHED_BY_CPU
            && phba->cfg_fcp_io_channel > 1) {
                cpu = smp_processor_id();
                if (cpu < phba->sli4_hba.num_present_cpu) {
                        cpup = phba->sli4_hba.cpu_map;
                        cpup += cpu;
                        return cpup->channel_id;
                }
        }
        chann = atomic_add_return(1, &phba->fcp_qidx);
        chann = chann % phba->cfg_fcp_io_channel;
        return chann;
}


/**
 * lpfc_scsi_cmd_iocb_cmpl - Scsi cmnd IOCB completion routine
 * @phba: The Hba for which this call is being executed.
 * @pIocbIn: The command IOCBQ for the scsi cmnd.
 * @pIocbOut: The response IOCBQ for the scsi cmnd.
 *
 * This routine assigns scsi command result by looking into response IOCB
 * status field appropriately. This routine handles QUEUE FULL condition as
 * well by ramping down device queue depth.
 **/
static void
lpfc_scsi_cmd_iocb_cmpl(struct lpfc_hba *phba, struct lpfc_iocbq *pIocbIn,
                        struct lpfc_iocbq *pIocbOut)
{
        struct lpfc_scsi_buf *lpfc_cmd =
                (struct lpfc_scsi_buf *) pIocbIn->context1;
        struct lpfc_vport      *vport = pIocbIn->vport;
        struct lpfc_rport_data *rdata = lpfc_cmd->rdata;
        struct lpfc_nodelist *pnode = rdata->pnode;
        struct scsi_cmnd *cmd;
        unsigned long flags;
        struct lpfc_fast_path_event *fast_path_evt;
        struct Scsi_Host *shost;
        uint32_t logit = LOG_FCP;

        atomic_inc(&phba->fc4ScsiIoCmpls);

        /* Sanity check on return of outstanding command */
        cmd = lpfc_cmd->pCmd;
        if (!cmd)
                return;
        shost = cmd->device->host;

        lpfc_cmd->result = (pIocbOut->iocb.un.ulpWord[4] & IOERR_PARAM_MASK);
        lpfc_cmd->status = pIocbOut->iocb.ulpStatus;
        /* pick up SLI4 exhange busy status from HBA */
        lpfc_cmd->exch_busy = pIocbOut->iocb_flag & LPFC_EXCHANGE_BUSY;

#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
        if (lpfc_cmd->prot_data_type) {
                struct scsi_dif_tuple *src = NULL;

                src =  (struct scsi_dif_tuple *)lpfc_cmd->prot_data_segment;
                /*
                 * Used to restore any changes to protection
                 * data for error injection.
                 */
                switch (lpfc_cmd->prot_data_type) {
                case LPFC_INJERR_REFTAG:
                        src->ref_tag =
                                lpfc_cmd->prot_data;
                        break;
                case LPFC_INJERR_APPTAG:
                        src->app_tag =
                                (uint16_t)lpfc_cmd->prot_data;
                        break;
                case LPFC_INJERR_GUARD:
                        src->guard_tag =
                                (uint16_t)lpfc_cmd->prot_data;
                        break;
                default:
                        break;
                }