// SPDX-License-Identifier: GPL-2.0-only
// Copyright 2014 Cisco Systems, Inc.  All rights reserved.

#include <linux/mempool.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/workqueue.h>
#include <linux/pci.h>
#include <linux/spinlock.h>
#include <linux/delay.h>
#include <linux/gfp.h>
#include <scsi/scsi.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_tcq.h>
#include <scsi/scsi_dbg.h>

#include "snic_io.h"
#include "snic.h"

#define snic_cmd_tag(sc)        (scsi_cmd_to_rq(sc)->tag)

const char *snic_state_str[] = {
        [SNIC_INIT]     = "SNIC_INIT",
        [SNIC_ERROR]    = "SNIC_ERROR",
        [SNIC_ONLINE]   = "SNIC_ONLINE",
        [SNIC_OFFLINE]  = "SNIC_OFFLINE",
        [SNIC_FWRESET]  = "SNIC_FWRESET",
};

static const char * const snic_req_state_str[] = {
        [SNIC_IOREQ_NOT_INITED] = "SNIC_IOREQ_NOT_INITED",
        [SNIC_IOREQ_PENDING]    = "SNIC_IOREQ_PENDING",
        [SNIC_IOREQ_ABTS_PENDING] = "SNIC_IOREQ_ABTS_PENDING",
        [SNIC_IOREQ_ABTS_COMPLETE] = "SNIC_IOREQ_ABTS_COMPLETE",
        [SNIC_IOREQ_LR_PENDING] = "SNIC_IOREQ_LR_PENDING",
        [SNIC_IOREQ_LR_COMPLETE] = "SNIC_IOREQ_LR_COMPLETE",
        [SNIC_IOREQ_COMPLETE]   = "SNIC_IOREQ_CMD_COMPLETE",
};

/* snic cmd status strings */
static const char * const snic_io_status_str[] = {
        [SNIC_STAT_IO_SUCCESS]  = "SNIC_STAT_IO_SUCCESS", /* 0x0 */
        [SNIC_STAT_INVALID_HDR] = "SNIC_STAT_INVALID_HDR",
        [SNIC_STAT_OUT_OF_RES]  = "SNIC_STAT_OUT_OF_RES",
        [SNIC_STAT_INVALID_PARM] = "SNIC_STAT_INVALID_PARM",
        [SNIC_STAT_REQ_NOT_SUP] = "SNIC_STAT_REQ_NOT_SUP",
        [SNIC_STAT_IO_NOT_FOUND] = "SNIC_STAT_IO_NOT_FOUND",
        [SNIC_STAT_ABORTED]     = "SNIC_STAT_ABORTED",
        [SNIC_STAT_TIMEOUT]     = "SNIC_STAT_TIMEOUT",
        [SNIC_STAT_SGL_INVALID] = "SNIC_STAT_SGL_INVALID",
        [SNIC_STAT_DATA_CNT_MISMATCH] = "SNIC_STAT_DATA_CNT_MISMATCH",
        [SNIC_STAT_FW_ERR]      = "SNIC_STAT_FW_ERR",
        [SNIC_STAT_ITMF_REJECT] = "SNIC_STAT_ITMF_REJECT",
        [SNIC_STAT_ITMF_FAIL]   = "SNIC_STAT_ITMF_FAIL",
        [SNIC_STAT_ITMF_INCORRECT_LUN] = "SNIC_STAT_ITMF_INCORRECT_LUN",
        [SNIC_STAT_CMND_REJECT] = "SNIC_STAT_CMND_REJECT",
        [SNIC_STAT_DEV_OFFLINE] = "SNIC_STAT_DEV_OFFLINE",
        [SNIC_STAT_NO_BOOTLUN]  = "SNIC_STAT_NO_BOOTLUN",
        [SNIC_STAT_SCSI_ERR]    = "SNIC_STAT_SCSI_ERR",
        [SNIC_STAT_NOT_READY]   = "SNIC_STAT_NOT_READY",
        [SNIC_STAT_FATAL_ERROR] = "SNIC_STAT_FATAL_ERROR",
};

static void snic_scsi_cleanup(struct snic *, int);

const char *
snic_state_to_str(unsigned int state)
{
        if (state >= ARRAY_SIZE(snic_state_str) || !snic_state_str[state])
                return "Unknown";

        return snic_state_str[state];
}

static const char *
snic_io_status_to_str(unsigned int state)
{
        if ((state >= ARRAY_SIZE(snic_io_status_str)) ||
             (!snic_io_status_str[state]))
                return "Unknown";

        return snic_io_status_str[state];
}

static const char *
snic_ioreq_state_to_str(unsigned int state)
{
        if (state >= ARRAY_SIZE(snic_req_state_str) ||
                        !snic_req_state_str[state])
                return "Unknown";

        return snic_req_state_str[state];
}

static inline spinlock_t *
snic_io_lock_hash(struct snic *snic, struct scsi_cmnd *sc)
{
        u32 hash = snic_cmd_tag(sc) & (SNIC_IO_LOCKS - 1);

        return &snic->io_req_lock[hash];
}

static inline spinlock_t *
snic_io_lock_tag(struct snic *snic, int tag)
{
        return &snic->io_req_lock[tag & (SNIC_IO_LOCKS - 1)];
}

/* snic_release_req_buf : Releases snic_req_info */
static void
snic_release_req_buf(struct snic *snic,
                   struct snic_req_info *rqi,
                   struct scsi_cmnd *sc)
{
        struct snic_host_req *req = rqi_to_req(rqi);

        /* Freeing cmd without marking completion, not okay */
        SNIC_BUG_ON(!((CMD_STATE(sc) == SNIC_IOREQ_COMPLETE) ||
                      (CMD_STATE(sc) == SNIC_IOREQ_ABTS_COMPLETE) ||
                      (CMD_FLAGS(sc) & SNIC_DEV_RST_NOTSUP) ||
                      (CMD_FLAGS(sc) & SNIC_IO_INTERNAL_TERM_ISSUED) ||
                      (CMD_FLAGS(sc) & SNIC_DEV_RST_TERM_ISSUED) ||
                      (CMD_FLAGS(sc) & SNIC_SCSI_CLEANUP) ||
                      (CMD_STATE(sc) == SNIC_IOREQ_LR_COMPLETE)));

        SNIC_SCSI_DBG(snic->shost,
                      "Rel_req:sc %p:tag %x:rqi %p:ioreq %p:abt %p:dr %p: state %s:flags 0x%llx\n",
                      sc, snic_cmd_tag(sc), rqi, rqi->req, rqi->abort_req,
                      rqi->dr_req, snic_ioreq_state_to_str(CMD_STATE(sc)),
                      CMD_FLAGS(sc));

        if (req->u.icmnd.sense_addr)
                dma_unmap_single(&snic->pdev->dev,
                                 le64_to_cpu(req->u.icmnd.sense_addr),
                                 SCSI_SENSE_BUFFERSIZE,
                                 DMA_FROM_DEVICE);

        scsi_dma_unmap(sc);

        snic_req_free(snic, rqi);
} /* end of snic_release_req_buf */

/*
 * snic_queue_icmnd_req : Queues snic_icmnd request
 */
static int
snic_queue_icmnd_req(struct snic *snic,
                     struct snic_req_info *rqi,
                     struct scsi_cmnd *sc,
                     int sg_cnt)
{
        struct scatterlist *sg;
        struct snic_sg_desc *sgd;
        dma_addr_t pa = 0;
        struct scsi_lun lun;
        u16 flags = 0;
        int ret = 0;
        unsigned int i;

        if (sg_cnt) {
                flags = SNIC_ICMND_ESGL;
                sgd = (struct snic_sg_desc *) req_to_sgl(rqi->req);

                for_each_sg(scsi_sglist(sc), sg, sg_cnt, i) {
                        sgd->addr = cpu_to_le64(sg_dma_address(sg));
                        sgd->len = cpu_to_le32(sg_dma_len(sg));
                        sgd->_resvd = 0;
                        sgd++;
                }
        }

        pa = dma_map_single(&snic->pdev->dev,
                            sc->sense_buffer,
                            SCSI_SENSE_BUFFERSIZE,
                            DMA_FROM_DEVICE);
        if (dma_mapping_error(&snic->pdev->dev, pa)) {
                SNIC_HOST_ERR(snic->shost,
                              "QIcmnd:PCI Map Failed for sns buf %p tag %x\n",
                              sc->sense_buffer, snic_cmd_tag(sc));
                ret = -ENOMEM;

                return ret;
        }

        int_to_scsilun(sc->device->lun, &lun);
        if (sc->sc_data_direction == DMA_FROM_DEVICE)
                flags |= SNIC_ICMND_RD;
        if (sc->sc_data_direction == DMA_TO_DEVICE)
                flags |= SNIC_ICMND_WR;

        /* Initialize icmnd */
        snic_icmnd_init(rqi->req,
                        snic_cmd_tag(sc),
                        snic->config.hid, /* hid */
                        (ulong) rqi,
                        flags, /* command flags */
                        rqi->tgt_id,
                        lun.scsi_lun,
                        sc->cmnd,
                        sc->cmd_len,
                        scsi_bufflen(sc),
                        sg_cnt,
                        (ulong) req_to_sgl(rqi->req),
                        pa, /* sense buffer pa */
                        SCSI_SENSE_BUFFERSIZE);

        atomic64_inc(&snic->s_stats.io.active);
        ret = snic_queue_wq_desc(snic, rqi->req, rqi->req_len);
        if (ret) {
                atomic64_dec(&snic->s_stats.io.active);
                SNIC_HOST_ERR(snic->shost,
                              "QIcmnd: Queuing Icmnd Failed. ret = %d\n",
                              ret);
        } else
                snic_stats_update_active_ios(&snic->s_stats);

        return ret;
} /* end of snic_queue_icmnd_req */

/*
 * snic_issue_scsi_req : Prepares IO request and Issues to FW.
 */
static int
snic_issue_scsi_req(struct snic *snic,
                      struct snic_tgt *tgt,
                      struct scsi_cmnd *sc)
{
        struct snic_req_info *rqi = NULL;
        int sg_cnt = 0;
        int ret = 0;
        u32 tag = snic_cmd_tag(sc);
        u64 cmd_trc = 0, cmd_st_flags = 0;
        spinlock_t *io_lock = NULL;
        unsigned long flags;

        CMD_STATE(sc) = SNIC_IOREQ_NOT_INITED;
        CMD_FLAGS(sc) = SNIC_NO_FLAGS;
        sg_cnt = scsi_dma_map(sc);
        if (sg_cnt < 0) {
                SNIC_TRC((u16)snic->shost->host_no, tag, (ulong) sc, 0,
                         sc->cmnd[0], sg_cnt, CMD_STATE(sc));

                SNIC_HOST_ERR(snic->shost, "issue_sc:Failed to map SG List.\n");
                ret = -ENOMEM;

                goto issue_sc_end;
        }

        rqi = snic_req_init(snic, sg_cnt);
        if (!rqi) {
                scsi_dma_unmap(sc);
                ret = -ENOMEM;

                goto issue_sc_end;
        }

        rqi->tgt_id = tgt->id;
        rqi->sc = sc;

        CMD_STATE(sc) = SNIC_IOREQ_PENDING;
        CMD_SP(sc) = (char *) rqi;
        cmd_trc = SNIC_TRC_CMD(sc);
        CMD_FLAGS(sc) |= (SNIC_IO_INITIALIZED | SNIC_IO_ISSUED);
        cmd_st_flags = SNIC_TRC_CMD_STATE_FLAGS(sc);
        io_lock = snic_io_lock_hash(snic, sc);

        /* create wq desc and enqueue it */
        ret = snic_queue_icmnd_req(snic, rqi, sc, sg_cnt);
        if (ret) {
                SNIC_HOST_ERR(snic->shost,
                              "issue_sc: icmnd qing Failed for sc %p, err %d\n",
                              sc, ret);

                spin_lock_irqsave(io_lock, flags);
                rqi = (struct snic_req_info *) CMD_SP(sc);
                CMD_SP(sc) = NULL;
                CMD_STATE(sc) = SNIC_IOREQ_COMPLETE;
                CMD_FLAGS(sc) &= ~SNIC_IO_ISSUED; /* turn off the flag */
                spin_unlock_irqrestore(io_lock, flags);

                if (rqi)
                        snic_release_req_buf(snic, rqi, sc);

                SNIC_TRC(snic->shost->host_no, tag, (ulong) sc, 0, 0, 0,
                         SNIC_TRC_CMD_STATE_FLAGS(sc));
        } else {
                u32 io_sz = scsi_bufflen(sc) >> 9;
                u32 qtime = jiffies - rqi->start_time;
                struct snic_io_stats *iostats = &snic->s_stats.io;

                if (io_sz > atomic64_read(&iostats->max_io_sz))
                        atomic64_set(&iostats->max_io_sz, io_sz);

                if (qtime > atomic64_read(&iostats->max_qtime))
                        atomic64_set(&iostats->max_qtime, qtime);

                SNIC_SCSI_DBG(snic->shost,
                              "issue_sc:sc %p, tag %d queued to WQ.\n",
                              sc, tag);

                SNIC_TRC(snic->shost->host_no, tag, (ulong) sc, (ulong) rqi,
                         sg_cnt, cmd_trc, cmd_st_flags);
        }

issue_sc_end:

        return ret;
} /* end of snic_issue_scsi_req */


/*
 * snic_queuecommand
 * Routine to send a scsi cdb to LLD
 * Called with host_lock held and interrupts disabled
 */
enum scsi_qc_status snic_queuecommand(struct Scsi_Host *shost,
                                      struct scsi_cmnd *sc)
{
        struct snic_tgt *tgt = NULL;
        struct snic *snic = shost_priv(shost);
        int ret;

        tgt = starget_to_tgt(scsi_target(sc->device));
        ret = snic_tgt_chkready(tgt);
        if (ret) {
                SNIC_HOST_ERR(shost, "Tgt %p id %d Not Ready.\n", tgt, tgt->id);
                atomic64_inc(&snic->s_stats.misc.tgt_not_rdy);
                sc->result = ret;
                scsi_done(sc);

                return 0;
        }

        if (snic_get_state(snic) != SNIC_ONLINE) {
                SNIC_HOST_ERR(shost, "snic state is %s\n",
                              snic_state_str[snic_get_state(snic)]);

                return SCSI_MLQUEUE_HOST_BUSY;
        }
        atomic_inc(&snic->ios_inflight);

        SNIC_SCSI_DBG(shost, "sc %p Tag %d (sc %0x) lun %lld in snic_qcmd\n",
                      sc, snic_cmd_tag(sc), sc->cmnd[0], sc->device->lun);

        ret = snic_issue_scsi_req(snic, tgt, sc);
        if (ret) {
                SNIC_HOST_ERR(shost, "Failed to Q, Scsi Req w/ err %d.\n", ret);
                ret = SCSI_MLQUEUE_HOST_BUSY;
        }

        atomic_dec(&snic->ios_inflight);

        return ret;
} /* end of snic_queuecommand */

/*
 * snic_process_abts_pending_state:
 * caller should hold IO lock
 */
static void
snic_proc_tmreq_pending_state(struct snic *snic,
                              struct scsi_cmnd *sc,
                              u8 cmpl_status)
{
        int state = CMD_STATE(sc);

        if (state == SNIC_IOREQ_ABTS_PENDING)
                CMD_FLAGS(sc) |= SNIC_IO_ABTS_PENDING;
        else if (state == SNIC_IOREQ_LR_PENDING)
                CMD_FLAGS(sc) |= SNIC_DEV_RST_PENDING;
        else
                SNIC_BUG_ON(1);

        switch (cmpl_status) {
        case SNIC_STAT_IO_SUCCESS:
                CMD_FLAGS(sc) |= SNIC_IO_DONE;
                break;

        case SNIC_STAT_ABORTED:
                CMD_FLAGS(sc) |= SNIC_IO_ABORTED;
                break;

        default:
                SNIC_BUG_ON(1);
        }
}

/*
 * snic_process_io_failed_state:
 * Processes IO's error states
 */
static void
snic_process_io_failed_state(struct snic *snic,
                             struct snic_icmnd_cmpl *icmnd_cmpl,
                             struct scsi_cmnd *sc,
                             u8 cmpl_stat)
{
        int res = 0;

        switch (cmpl_stat) {
        case SNIC_STAT_TIMEOUT:         /* Req was timedout */
                atomic64_inc(&snic->s_stats.misc.io_tmo);
                res = DID_TIME_OUT;
                break;

        case SNIC_STAT_ABORTED:         /* Req was aborted */
                atomic64_inc(&snic->s_stats.misc.io_aborted);
                res = DID_ABORT;
                break;

        case SNIC_STAT_DATA_CNT_MISMATCH:/* Recv/Sent more/less data than exp */
                atomic64_inc(&snic->s_stats.misc.data_cnt_mismat);
                scsi_set_resid(sc, le32_to_cpu(icmnd_cmpl->resid));
                res = DID_ERROR;
                break;

        case SNIC_STAT_OUT_OF_RES: /* Out of resources to complete request */
                atomic64_inc(&snic->s_stats.fw.out_of_res);
                res = DID_REQUEUE;
                break;

        case SNIC_STAT_IO_NOT_FOUND:    /* Requested I/O was not found */
                atomic64_inc(&snic->s_stats.io.io_not_found);
                res = DID_ERROR;
                break;

        case SNIC_STAT_SGL_INVALID:     /* Req was aborted to due to sgl error*/
                atomic64_inc(&snic->s_stats.misc.sgl_inval);
                res = DID_ERROR;
                break;

        case SNIC_STAT_FW_ERR:          /* Req terminated due to FW Error */
                atomic64_inc(&snic->s_stats.fw.io_errs);
                res = DID_ERROR;
                break;

        case SNIC_STAT_SCSI_ERR:        /* FW hits SCSI Error */
                atomic64_inc(&snic->s_stats.fw.scsi_errs);
                break;

        case SNIC_STAT_NOT_READY:       /* XPT yet to initialize */
        case SNIC_STAT_DEV_OFFLINE:     /* Device offline */
                res = DID_NO_CONNECT;
                break;

        case SNIC_STAT_INVALID_HDR:     /* Hdr contains invalid data */
        case SNIC_STAT_INVALID_PARM:    /* Some param in req is invalid */
        case SNIC_STAT_REQ_NOT_SUP:     /* Req type is not supported */
        case SNIC_STAT_CMND_REJECT:     /* Req rejected */
        case SNIC_STAT_FATAL_ERROR:     /* XPT Error */
        default:
                SNIC_SCSI_DBG(snic->shost,
                              "Invalid Hdr/Param or Req Not Supported or Cmnd Rejected or Device Offline. or Unknown\n");
                res = DID_ERROR;
                break;
        }

        SNIC_HOST_ERR(snic->shost, "fw returns failed status %s flags 0x%llx\n",
                      snic_io_status_to_str(cmpl_stat), CMD_FLAGS(sc));

        /* Set sc->result */
        sc->result = (res << 16) | icmnd_cmpl->scsi_status;
} /* end of snic_process_io_failed_state */

/*
 * snic_tmreq_pending : is task management in progress.
 */
static int
snic_tmreq_pending(struct scsi_cmnd *sc)
{
        int state = CMD_STATE(sc);

        return ((state == SNIC_IOREQ_ABTS_PENDING) ||
                        (state == SNIC_IOREQ_LR_PENDING));
}

/*
 * snic_process_icmnd_cmpl_status:
 * Caller should hold io_lock
 */
static int
snic_process_icmnd_cmpl_status(struct snic *snic,
                               struct snic_icmnd_cmpl *icmnd_cmpl,
                               u8 cmpl_stat,
                               struct scsi_cmnd *sc)
{
        u8 scsi_stat = icmnd_cmpl->scsi_status;
        int ret = 0;

        /* Mark the IO as complete */
        CMD_STATE(sc) = SNIC_IOREQ_COMPLETE;

        if (likely(cmpl_stat == SNIC_STAT_IO_SUCCESS)) {
                sc->result = (DID_OK << 16) | scsi_stat;

                /* Update SCSI Cmd with resid value */
                scsi_set_resid(sc, le32_to_cpu(icmnd_cmpl->resid));

                if (icmnd_cmpl->flags & SNIC_ICMND_CMPL_UNDR_RUN)
                        atomic64_inc(&snic->s_stats.misc.io_under_run);

                if (icmnd_cmpl->scsi_status == SAM_STAT_TASK_SET_FULL)
                        atomic64_inc(&snic->s_stats.misc.qfull);

                ret = 0;
        } else {
                snic_process_io_failed_state(snic, icmnd_cmpl, sc, cmpl_stat);
                atomic64_inc(&snic->s_stats.io.fail);
                SNIC_HOST_ERR(snic->shost,
                              "icmnd_cmpl: IO Failed : Hdr Status %s flags 0x%llx\n",
                              snic_io_status_to_str(cmpl_stat), CMD_FLAGS(sc));
                ret = 1;
        }

        return ret;
} /* end of snic_process_icmnd_cmpl_status */


/*
 * snic_icmnd_cmpl_handler
 * Routine to handle icmnd completions
 */
static void
snic_icmnd_cmpl_handler(struct snic *snic, struct snic_fw_req *fwreq)
{
        u8 typ, hdr_stat;
        u32 cmnd_id, hid;
        ulong ctx;
        struct scsi_cmnd *sc = NULL;
        struct snic_icmnd_cmpl *icmnd_cmpl = NULL;
        struct snic_host_req *req = NULL;
        struct snic_req_info *rqi = NULL;
        unsigned long flags, start_time;
        spinlock_t *io_lock;
        u8 sc_stat = 0;

        snic_io_hdr_dec(&fwreq->hdr, &typ, &hdr_stat, &cmnd_id, &hid, &ctx);
        icmnd_cmpl = &fwreq->u.icmnd_cmpl;
        sc_stat = icmnd_cmpl->scsi_status;

        SNIC_SCSI_DBG(snic->shost,
                      "Icmnd_cmpl: type = %x, hdr_stat = %x, cmnd_id = %x, hid = %x,i ctx = %lx\n",
                      typ, hdr_stat, cmnd_id, hid, ctx);

        if (cmnd_id >= snic->max_tag_id) {
                SNIC_HOST_ERR(snic->shost,
                              "Icmnd_cmpl:Tag Error:Out of Range Tag %d, hdr status = %s\n",
                              cmnd_id, snic_io_status_to_str(hdr_stat));
                return;
        }

        sc = scsi_host_find_tag(snic->shost, cmnd_id);
        WARN_ON_ONCE(!sc);

        if (!sc) {
                atomic64_inc(&snic->s_stats.io.sc_null);
                SNIC_HOST_ERR(snic->shost,
                              "Icmnd_cmpl: Scsi Cmnd Not found, sc = NULL Hdr Status = %s tag = 0x%x fwreq = 0x%p\n",
                              snic_io_status_to_str(hdr_stat),
                              cmnd_id,
                              fwreq);

                SNIC_TRC(snic->shost->host_no, cmnd_id, 0,
                         ((u64)hdr_stat << 16 |
                          (u64)sc_stat << 8 | (u64)icmnd_cmpl->flags),
                         (ulong) fwreq, le32_to_cpu(icmnd_cmpl->resid), ctx);

                return;
        }

        io_lock = snic_io_lock_hash(snic, sc);

        spin_lock_irqsave(io_lock, flags);
        rqi = (struct snic_req_info *) CMD_SP(sc);
        SNIC_SCSI_DBG(snic->shost,
                      "Icmnd_cmpl:lun %lld sc %p cmd %xtag %d flags 0x%llx rqi %p\n",
                      sc->device->lun, sc, sc->cmnd[0], snic_cmd_tag(sc),
                      CMD_FLAGS(sc), rqi);

        if (CMD_FLAGS(sc) & SNIC_HOST_RESET_CMD_TERM) {
                spin_unlock_irqrestore(io_lock, flags);

                return;
        }

        SNIC_BUG_ON(rqi != (struct snic_req_info *)ctx);
        WARN_ON_ONCE(req);
        if (!rqi) {
                atomic64_inc(&snic->s_stats.io.req_null);
                CMD_FLAGS(sc) |= SNIC_IO_REQ_NULL;
                spin_unlock_irqrestore(io_lock, flags);

                SNIC_HOST_ERR(snic->shost,
                              "Icmnd_cmpl:Host Req Not Found(null), Hdr Status %s, Tag 0x%x, sc 0x%p flags 0x%llx\n",
                              snic_io_status_to_str(hdr_stat),
                              cmnd_id, sc, CMD_FLAGS(sc));
                return;
        }

        rqi = (struct snic_req_info *) ctx;
        start_time = rqi->start_time;

        /* firmware completed the io */
        rqi->io_cmpl = 1;

        /*
         * if SCSI-ML has already issued abort on this command,
         * ignore completion of the IO. The abts path will clean it up
         */
        if (unlikely(snic_tmreq_pending(sc))) {
                snic_proc_tmreq_pending_state(snic, sc, hdr_stat);
                spin_unlock_irqrestore(io_lock, flags);

                snic_stats_update_io_cmpl(&snic->s_stats);

                /* Expected value is SNIC_STAT_ABORTED */
                if (likely(hdr_stat == SNIC_STAT_ABORTED))
                        return;

                SNIC_SCSI_DBG(snic->shost,
                              "icmnd_cmpl:TM Req Pending(%s), Hdr Status %s sc 0x%p scsi status %x resid %d flags 0x%llx\n",
                              snic_ioreq_state_to_str(CMD_STATE(sc)),
                              snic_io_status_to_str(hdr_stat),
                              sc, sc_stat, le32_to_cpu(icmnd_cmpl->resid),
                              CMD_FLAGS(sc));

                SNIC_TRC(snic->shost->host_no, cmnd_id, (ulong) sc,
                         jiffies_to_msecs(jiffies - start_time), (ulong) fwreq,
                         SNIC_TRC_CMD(sc), SNIC_TRC_CMD_STATE_FLAGS(sc));

                return;
        }

        if (snic_process_icmnd_cmpl_status(snic, icmnd_cmpl, hdr_stat, sc)) {
                scsi_print_command(sc);
                SNIC_HOST_ERR(snic->shost,
                              "icmnd_cmpl:IO Failed, sc 0x%p Tag %d Cmd %x Hdr Status %s flags 0x%llx\n",
                              sc, sc->cmnd[0], cmnd_id,
                              snic_io_status_to_str(hdr_stat), CMD_FLAGS(sc));
        }

        /* Break link with the SCSI Command */
        CMD_SP(sc) = NULL;
        CMD_FLAGS(sc) |= SNIC_IO_DONE;

        spin_unlock_irqrestore(io_lock, flags);

        /* For now, consider only successful IO. */
        snic_calc_io_process_time(snic, rqi);

        snic_release_req_buf(snic, rqi, sc);

        SNIC_TRC(snic->shost->host_no, cmnd_id, (ulong) sc,
                 jiffies_to_msecs(jiffies - start_time), (ulong) fwreq,
                 SNIC_TRC_CMD(sc), SNIC_TRC_CMD_STATE_FLAGS(sc));


        scsi_done(sc);

        snic_stats_update_io_cmpl(&snic->s_stats);
} /* end of snic_icmnd_cmpl_handler */

static void
snic_proc_dr_cmpl_locked(struct snic *snic,
                         struct snic_fw_req *fwreq,
                         u8 cmpl_stat,
                         u32 cmnd_id,
                         struct scsi_cmnd *sc)
{
        struct snic_req_info *rqi = (struct snic_req_info *) CMD_SP(sc);
        u32 start_time = rqi->start_time;

        CMD_LR_STATUS(sc) = cmpl_stat;

        SNIC_SCSI_DBG(snic->shost, "itmf_cmpl: Cmd State = %s\n",
                      snic_ioreq_state_to_str(CMD_STATE(sc)));

        if (CMD_STATE(sc) == SNIC_IOREQ_ABTS_PENDING) {
                CMD_FLAGS(sc) |= SNIC_DEV_RST_ABTS_PENDING;

                SNIC_TRC(snic->shost->host_no, cmnd_id, (ulong) sc,
                         jiffies_to_msecs(jiffies - start_time),
                         (ulong) fwreq, 0, SNIC_TRC_CMD_STATE_FLAGS(sc));

                SNIC_SCSI_DBG(snic->shost,
                              "itmf_cmpl: Terminate Pending Dev Reset Cmpl Recvd.id %x, status %s flags 0x%llx\n",
                              (int)(cmnd_id & SNIC_TAG_MASK),
                              snic_io_status_to_str(cmpl_stat),
                              CMD_FLAGS(sc));

                return;
        }


        if (CMD_FLAGS(sc) & SNIC_DEV_RST_TIMEDOUT) {
                SNIC_TRC(snic->shost->host_no, cmnd_id, (ulong) sc,
                         jiffies_to_msecs(jiffies - start_time),
                         (ulong) fwreq, 0, SNIC_TRC_CMD_STATE_FLAGS(sc));

                SNIC_SCSI_DBG(snic->shost,
                              "itmf_cmpl:Dev Reset Completion Received after timeout. id %d cmpl status %s flags 0x%llx\n",
                              (int)(cmnd_id & SNIC_TAG_MASK),
                              snic_io_status_to_str(cmpl_stat),
                              CMD_FLAGS(sc));

                return;
        }

        CMD_STATE(sc) = SNIC_IOREQ_LR_COMPLETE;
        CMD_FLAGS(sc) |= SNIC_DEV_RST_DONE;

        SNIC_SCSI_DBG(snic->shost,
                      "itmf_cmpl:Dev Reset Cmpl Recvd id %d cmpl status %s flags 0x%llx\n",
                      (int)(cmnd_id & SNIC_TAG_MASK),
                      snic_io_status_to_str(cmpl_stat),
                      CMD_FLAGS(sc));

        if (rqi->dr_done)
                complete(rqi->dr_done);
} /* end of snic_proc_dr_cmpl_locked */

/*
 * snic_update_abort_stats : Updates abort stats based on completion status.
 */
static void
snic_update_abort_stats(struct snic *snic, u8 cmpl_stat)
{
        struct snic_abort_stats *abt_stats = &snic->s_stats.abts;

        SNIC_SCSI_DBG(snic->shost, "Updating Abort stats.\n");

        switch (cmpl_stat) {
        case  SNIC_STAT_IO_SUCCESS:
                break;

        case SNIC_STAT_TIMEOUT:
                atomic64_inc(&abt_stats->fw_tmo);
                break;

        case SNIC_STAT_IO_NOT_FOUND:
                atomic64_inc(&abt_stats->io_not_found);
                break;

        default:
                atomic64_inc(&abt_stats->fail);
                break;
        }
}

static int
snic_process_itmf_cmpl(struct snic *snic,
                       struct snic_fw_req *fwreq,
                       u32 cmnd_id,
                       u8 cmpl_stat,
                       struct scsi_cmnd *sc)
{
        struct snic_req_info *rqi = NULL;
        u32 tm_tags = 0;
        spinlock_t *io_lock = NULL;
        unsigned long flags;
        u32 start_time = 0;
        int ret = 0;

        io_lock = snic_io_lock_hash(snic, sc);
        spin_lock_irqsave(io_lock, flags);
        if (CMD_FLAGS(sc) & SNIC_HOST_RESET_CMD_TERM) {
                spin_unlock_irqrestore(io_lock, flags);

                return ret;
        }
        rqi = (struct snic_req_info *) CMD_SP(sc);
        WARN_ON_ONCE(!rqi);

        if (!rqi) {
                atomic64_inc(&snic->s_stats.io.req_null);
                spin_unlock_irqrestore(io_lock, flags);
                CMD_FLAGS(sc) |= SNIC_IO_ABTS_TERM_REQ_NULL;
                SNIC_HOST_ERR(snic->shost,
                              "itmf_cmpl: rqi is null,Hdr stat = %s Tag = 0x%x sc = 0x%p flags 0x%llx\n",
                              snic_io_status_to_str(cmpl_stat), cmnd_id, sc,
                              CMD_FLAGS(sc));

                return ret;
        }

        /* Extract task management flags */
        tm_tags = cmnd_id & ~(SNIC_TAG_MASK);

        start_time = rqi->start_time;
        cmnd_id &= (SNIC_TAG_MASK);

        switch (tm_tags) {
        case SNIC_TAG_ABORT:
                /* Abort only issued on cmd */
                snic_update_abort_stats(snic, cmpl_stat);

                if (CMD_STATE(sc) != SNIC_IOREQ_ABTS_PENDING) {
                        /* This is a late completion. Ignore it. */
                        ret = -1;
                        spin_unlock_irqrestore(io_lock, flags);
                        break;
                }

                CMD_STATE(sc) = SNIC_IOREQ_ABTS_COMPLETE;
                CMD_ABTS_STATUS(sc) = cmpl_stat;
                CMD_FLAGS(sc) |= SNIC_IO_ABTS_TERM_DONE;

                SNIC_SCSI_DBG(snic->shost,
                              "itmf_cmpl:Abort Cmpl Recvd.Tag 0x%x Status %s flags 0x%llx\n",
                              cmnd_id,
                              snic_io_status_to_str(cmpl_stat),
                              CMD_FLAGS(sc));

                /*
                 * If scsi_eh thread is blocked waiting for abts complete,
                 * signal completion to it. IO will be cleaned in the thread,
                 * else clean it in this context.
                 */
                if (rqi->abts_done) {
                        complete(rqi->abts_done);
                        spin_unlock_irqrestore(io_lock, flags);

                        break; /* jump out */
                }

                CMD_SP(sc) = NULL;
                sc->result = (DID_ERROR << 16);
                SNIC_SCSI_DBG(snic->shost,
                              "itmf_cmpl: Completing IO. sc %p flags 0x%llx\n",
                              sc, CMD_FLAGS(sc));

                spin_unlock_irqrestore(io_lock, flags);

                snic_release_req_buf(snic, rqi, sc);

                SNIC_TRC(snic->shost->host_no, cmnd_id, (ulong) sc,
                         jiffies_to_msecs(jiffies - start_time),
                         (ulong) fwreq, SNIC_TRC_CMD(sc),
                         SNIC_TRC_CMD_STATE_FLAGS(sc));

                scsi_done(sc);

                break;

        case SNIC_TAG_DEV_RST:
        case SNIC_TAG_DEV_RST | SNIC_TAG_IOCTL_DEV_RST:
                snic_proc_dr_cmpl_locked(snic, fwreq, cmpl_stat, cmnd_id, sc);
                spin_unlock_irqrestore(io_lock, flags);
                ret = 0;

                break;

        case SNIC_TAG_ABORT | SNIC_TAG_DEV_RST:
                /* Abort and terminate completion of device reset req */

                CMD_STATE(sc) = SNIC_IOREQ_ABTS_COMPLETE;
                CMD_ABTS_STATUS(sc) = cmpl_stat;
                CMD_FLAGS(sc) |= SNIC_DEV_RST_DONE;

                SNIC_SCSI_DBG(snic->shost,
                              "itmf_cmpl:dev reset abts cmpl recvd. id %d status %s flags 0x%llx\n",
                              cmnd_id, snic_io_status_to_str(cmpl_stat),
                              CMD_FLAGS(sc));

                if (rqi->abts_done)
                        complete(rqi->abts_done);

                spin_unlock_irqrestore(io_lock, flags);

                break;

        default:
                spin_unlock_irqrestore(io_lock, flags);
                SNIC_HOST_ERR(snic->shost,
                              "itmf_cmpl: Unknown TM tag bit 0x%x\n", tm_tags);

                SNIC_HOST_ERR(snic->shost,
                              "itmf_cmpl:Unexpected itmf io stat %s Tag = 0x%x flags 0x%llx\n",
                              snic_ioreq_state_to_str(CMD_STATE(sc)),
                              cmnd_id,
                              CMD_FLAGS(sc));
                ret = -1;
                SNIC_BUG_ON(1);

                break;
        }

        return ret;
} /* end of snic_process_itmf_cmpl_status */

/*
 * snic_itmf_cmpl_handler.
 * Routine to handle itmf completions.
 */
static void
snic_itmf_cmpl_handler(struct snic *snic, struct snic_fw_req *fwreq)
{
        struct scsi_cmnd  *sc = NULL;
        struct snic_req_info *rqi = NULL;
        struct snic_itmf_cmpl *itmf_cmpl = NULL;
        ulong ctx;
        u32 cmnd_id;
        u32 hid;
        u8 typ;
        u8 hdr_stat;

        snic_io_hdr_dec(&fwreq->hdr, &typ, &hdr_stat, &cmnd_id, &hid, &ctx);
        SNIC_SCSI_DBG(snic->shost,
                      "Itmf_cmpl: %s: type = %x, hdr_stat = %x, cmnd_id = %x, hid = %x,ctx = %lx\n",
                      __func__, typ, hdr_stat, cmnd_id, hid, ctx);

        itmf_cmpl = &fwreq->u.itmf_cmpl;
        SNIC_SCSI_DBG(snic->shost,
                      "Itmf_cmpl: nterm %u , flags 0x%x\n",
                      le32_to_cpu(itmf_cmpl->nterminated), itmf_cmpl->flags);

        /* spl case, dev reset issued through ioctl */
        if (cmnd_id & SNIC_TAG_IOCTL_DEV_RST) {
                rqi = (struct snic_req_info *) ctx;
                sc = rqi->sc;

                goto ioctl_dev_rst;
        }

        if ((cmnd_id & SNIC_TAG_MASK) >= snic->max_tag_id) {
                SNIC_HOST_ERR(snic->shost,
                              "Itmf_cmpl: Tag 0x%x out of Range,HdrStat %s\n",
                              cmnd_id, snic_io_status_to_str(hdr_stat));
                SNIC_BUG_ON(1);

                return;
        }

        sc = scsi_host_find_tag(snic->shost, cmnd_id & SNIC_TAG_MASK);
        WARN_ON_ONCE(!sc);

ioctl_dev_rst:
        if (!sc) {
                atomic64_inc(&snic->s_stats.io.sc_null);
                SNIC_HOST_ERR(snic->shost,
                              "Itmf_cmpl: sc is NULL - Hdr Stat %s Tag 0x%x\n",
                              snic_io_status_to_str(hdr_stat), cmnd_id);

                return;
        }

        snic_process_itmf_cmpl(snic, fwreq, cmnd_id, hdr_stat, sc);
} /* end of snic_itmf_cmpl_handler */



static void
snic_hba_reset_scsi_cleanup(struct snic *snic, struct scsi_cmnd *sc)
{
        struct snic_stats *st = &snic->s_stats;
        long act_ios = 0, act_fwreqs = 0;

        SNIC_SCSI_DBG(snic->shost, "HBA Reset scsi cleanup.\n");
        snic_scsi_cleanup(snic, snic_cmd_tag(sc));

        /* Update stats on pending IOs */
        act_ios = atomic64_read(&st->io.active);
        atomic64_add(act_ios, &st->io.compl);
        atomic64_sub(act_ios, &st->io.active);

        act_fwreqs = atomic64_read(&st->fw.actv_reqs);
        atomic64_sub(act_fwreqs, &st->fw.actv_reqs);
}

/*
 * snic_hba_reset_cmpl_handler :
 *
 * Notes :
 * 1. Cleanup all the scsi cmds, release all snic specific cmds
 * 2. Issue Report Targets in case of SAN targets
 */
static int
snic_hba_reset_cmpl_handler(struct snic *snic, struct snic_fw_req *fwreq)
{
        ulong ctx;
        u32 cmnd_id;
        u32 hid;
        u8 typ;
        u8 hdr_stat;
        struct scsi_cmnd *sc = NULL;
        struct snic_req_info *rqi = NULL;
        spinlock_t *io_lock = NULL;
        unsigned long flags, gflags;
        int ret = 0;

        snic_io_hdr_dec(&fwreq->hdr, &typ, &hdr_stat, &cmnd_id, &hid, &ctx);
        SNIC_HOST_INFO(snic->shost,
                       "reset_cmpl:Tag %d ctx %lx cmpl status %s HBA Reset Completion received.\n",
                       cmnd_id, ctx, snic_io_status_to_str(hdr_stat));

        SNIC_SCSI_DBG(snic->shost,
                      "reset_cmpl: type = %x, hdr_stat = %x, cmnd_id = %x, hid = %x, ctx = %lx\n",
                      typ, hdr_stat, cmnd_id, hid, ctx);

        /* spl case, host reset issued through ioctl */
        if (cmnd_id == SCSI_NO_TAG) {
                rqi = (struct snic_req_info *) ctx;
                SNIC_HOST_INFO(snic->shost,
                               "reset_cmpl:Tag %d ctx %lx cmpl stat %s\n",
                               cmnd_id, ctx, snic_io_status_to_str(hdr_stat));
                sc = rqi->sc;

                goto ioctl_hba_rst;
        }

        if (cmnd_id >= snic->max_tag_id) {
                SNIC_HOST_ERR(snic->shost,
                              "reset_cmpl: Tag 0x%x out of Range,HdrStat %s\n",
                              cmnd_id, snic_io_status_to_str(hdr_stat));
                SNIC_BUG_ON(1);

                return 1;
        }

        sc = scsi_host_find_tag(snic->shost, cmnd_id);
ioctl_hba_rst:
        if (!sc) {
                atomic64_inc(&snic->s_stats.io.sc_null);
                SNIC_HOST_ERR(snic->shost,
                              "reset_cmpl: sc is NULL - Hdr Stat %s Tag 0x%x\n",
                              snic_io_status_to_str(hdr_stat), cmnd_id);
                ret = 1;

                return ret;
        }

        SNIC_HOST_INFO(snic->shost,
                       "reset_cmpl: sc %p rqi %p Tag %d flags 0x%llx\n",
                       sc, rqi, cmnd_id, CMD_FLAGS(sc));

        io_lock = snic_io_lock_hash(snic, sc);
        spin_lock_irqsave(io_lock, flags);

        if (!snic->remove_wait) {
                spin_unlock_irqrestore(io_lock, flags);
                SNIC_HOST_ERR(snic->shost,
                              "reset_cmpl:host reset completed after timeout\n");
                ret = 1;

                return ret;
        }

        rqi = (struct snic_req_info *) CMD_SP(sc);
        WARN_ON_ONCE(!rqi);

        if (!rqi) {
                atomic64_inc(&snic->s_stats.io.req_null);
                spin_unlock_irqrestore(io_lock, flags);
                CMD_FLAGS(sc) |= SNIC_IO_ABTS_TERM_REQ_NULL;
                SNIC_HOST_ERR(snic->shost,
                              "reset_cmpl: rqi is null,Hdr stat %s Tag 0x%x sc 0x%p flags 0x%llx\n",
                              snic_io_status_to_str(hdr_stat), cmnd_id, sc,
                              CMD_FLAGS(sc));

                ret = 1;

                return ret;
        }
        /* stats */
        spin_unlock_irqrestore(io_lock, flags);

        /* scsi cleanup */
        snic_hba_reset_scsi_cleanup(snic, sc);

        SNIC_BUG_ON(snic_get_state(snic) != SNIC_OFFLINE &&
                    snic_get_state(snic) != SNIC_FWRESET);

        /* Careful locking between snic_lock and io lock */
        spin_lock_irqsave(io_lock, flags);
        spin_lock_irqsave(&snic->snic_lock, gflags);
        if (snic_get_state(snic) == SNIC_FWRESET)
                snic_set_state(snic, SNIC_ONLINE);
        spin_unlock_irqrestore(&snic->snic_lock, gflags);

        if (snic->remove_wait)
                complete(snic->remove_wait);

        spin_unlock_irqrestore(io_lock, flags);
        atomic64_inc(&snic->s_stats.reset.hba_reset_cmpl);

        ret = 0;
        /* Rediscovery is for SAN */
        if (snic->config.xpt_type == SNIC_DAS)
                        return ret;

        SNIC_SCSI_DBG(snic->shost, "reset_cmpl: Queuing discovery work.\n");
        queue_work(snic_glob->event_q, &snic->disc_work);

        return ret;
}

static void
snic_msg_ack_handler(struct snic *snic, struct snic_fw_req *fwreq)
{
        SNIC_HOST_INFO(snic->shost, "Message Ack Received.\n");

        SNIC_ASSERT_NOT_IMPL(1);
}

static void
snic_aen_handler(struct snic *snic, struct snic_fw_req *fwreq)
{
        u8 typ, hdr_stat;
        u32 cmnd_id, hid;
        ulong ctx;
        struct snic_async_evnotify *aen = &fwreq->u.async_ev;
        u32 event_id = 0;

        snic_io_hdr_dec(&fwreq->hdr, &typ, &hdr_stat, &cmnd_id, &hid, &ctx);
        SNIC_SCSI_DBG(snic->shost,
                      "aen: type = %x, hdr_stat = %x, cmnd_id = %x, hid = %x, ctx = %lx\n",
                      typ, hdr_stat, cmnd_id, hid, ctx);

        event_id = le32_to_cpu(aen->ev_id);

        switch (event_id) {
        case SNIC_EV_TGT_OFFLINE:
                SNIC_HOST_INFO(snic->shost, "aen:TGT_OFFLINE Event Recvd.\n");
                break;

        case SNIC_EV_TGT_ONLINE:
                SNIC_HOST_INFO(snic->shost, "aen:TGT_ONLINE Event Recvd.\n");
                break;

        case SNIC_EV_LUN_OFFLINE:
                SNIC_HOST_INFO(snic->shost, "aen:LUN_OFFLINE Event Recvd.\n");
                break;

        case SNIC_EV_LUN_ONLINE:
                SNIC_HOST_INFO(snic->shost, "aen:LUN_ONLINE Event Recvd.\n");
                break;

        case SNIC_EV_CONF_CHG:
                SNIC_HOST_INFO(snic->shost, "aen:Config Change Event Recvd.\n");
                break;

        case SNIC_EV_TGT_ADDED:
                SNIC_HOST_INFO(snic->shost, "aen:TGT_ADD Event Recvd.\n");
                break;

        case SNIC_EV_TGT_DELTD:
                SNIC_HOST_INFO(snic->shost, "aen:TGT_DEL Event Recvd.\n");
                break;

        case SNIC_EV_LUN_ADDED:
                SNIC_HOST_INFO(snic->shost, "aen:LUN_ADD Event Recvd.\n");
                break;

        case SNIC_EV_LUN_DELTD:
                SNIC_HOST_INFO(snic->shost, "aen:LUN_DEL Event Recvd.\n");
                break;

        case SNIC_EV_DISC_CMPL:
                SNIC_HOST_INFO(snic->shost, "aen:DISC_CMPL Event Recvd.\n");
                break;

        default:
                SNIC_HOST_INFO(snic->shost, "aen:Unknown Event Recvd.\n");
                SNIC_BUG_ON(1);
                break;
        }

        SNIC_ASSERT_NOT_IMPL(1);
} /* end of snic_aen_handler */

/*
 * snic_io_cmpl_handler
 * Routine to process CQ entries(IO Completions) posted by fw.
 */
static int
snic_io_cmpl_handler(struct vnic_dev *vdev,
                     unsigned int cq_idx,
                     struct snic_fw_req *fwreq)
{
        struct snic *snic = svnic_dev_priv(vdev);
        u64 start = jiffies, cmpl_time;

        snic_print_desc(__func__, (char *)fwreq, sizeof(*fwreq));

        /* Update FW Stats */
        if ((fwreq->hdr.type >= SNIC_RSP_REPORT_TGTS_CMPL) &&
                (fwreq->hdr.type <= SNIC_RSP_BOOT_LUNS_CMPL))
                atomic64_dec(&snic->s_stats.fw.actv_reqs);

        SNIC_BUG_ON((fwreq->hdr.type > SNIC_RSP_BOOT_LUNS_CMPL) &&
                    (fwreq->hdr.type < SNIC_MSG_ASYNC_EVNOTIFY));

        /* Check for snic subsys errors */
        switch (fwreq->hdr.status) {
        case SNIC_STAT_NOT_READY:       /* XPT yet to initialize */
                SNIC_HOST_ERR(snic->shost,
                              "sNIC SubSystem is NOT Ready.\n");
                break;

        case SNIC_STAT_FATAL_ERROR:     /* XPT Error */
                SNIC_HOST_ERR(snic->shost,
                              "sNIC SubSystem in Unrecoverable State.\n");
                break;
        }

        switch (fwreq->hdr.type) {
        case SNIC_RSP_EXCH_VER_CMPL:
                snic_io_exch_ver_cmpl_handler(snic, fwreq);
                break;

        case SNIC_RSP_REPORT_TGTS_CMPL:
                snic_report_tgt_cmpl_handler(snic, fwreq);
                break;

        case SNIC_RSP_ICMND_CMPL:
                snic_icmnd_cmpl_handler(snic, fwreq);
                break;

        case SNIC_RSP_ITMF_CMPL:
                snic_itmf_cmpl_handler(snic, fwreq);
                break;

        case SNIC_RSP_HBA_RESET_CMPL:
                snic_hba_reset_cmpl_handler(snic, fwreq);
                break;

        case SNIC_MSG_ACK:
                snic_msg_ack_handler(snic, fwreq);
                break;

        case SNIC_MSG_ASYNC_EVNOTIFY:
                snic_aen_handler(snic, fwreq);
                break;

        default:
                SNIC_BUG_ON(1);
                SNIC_SCSI_DBG(snic->shost,
                              "Unknown Firmware completion request type %d\n",
                              fwreq->hdr.type);
                break;
        }

        /* Update Stats */
        cmpl_time = jiffies - start;
        if (cmpl_time > atomic64_read(&snic->s_stats.io.max_cmpl_time))
                atomic64_set(&snic->s_stats.io.max_cmpl_time, cmpl_time);

        return 0;
} /* end of snic_io_cmpl_handler */

/*
 * snic_fwcq_cmpl_handler
 * Routine to process fwCQ
 * This CQ is independent, and not associated with wq/rq/wq_copy queues
 */
int
snic_fwcq_cmpl_handler(struct snic *snic, int io_cmpl_work)
{
        unsigned int num_ent = 0;       /* number cq entries processed */
        unsigned int cq_idx;
        unsigned int nent_per_cq;
        struct snic_misc_stats *misc_stats = &snic->s_stats.misc;

        for (cq_idx = snic->wq_count; cq_idx < snic->cq_count; cq_idx++) {
                nent_per_cq = vnic_cq_fw_service(&snic->cq[cq_idx],
                                                 snic_io_cmpl_handler,
                                                 io_cmpl_work);
                num_ent += nent_per_cq;

                if (nent_per_cq > atomic64_read(&misc_stats->max_cq_ents))
                        atomic64_set(&misc_stats->max_cq_ents, nent_per_cq);
        }

        return num_ent;
} /* end of snic_fwcq_cmpl_handler */

/*
 * snic_queue_itmf_req: Common API to queue Task Management requests.
 * Use rqi->tm_tag for passing special tags.
 * @req_id : aborted request's tag, -1 for lun reset.
 */
static int
snic_queue_itmf_req(struct snic *snic,
                    struct snic_host_req *tmreq,
                    struct scsi_cmnd *sc,
                    u32 tmf,
                    u32 req_id)
{
        struct snic_req_info *rqi = req_to_rqi(tmreq);
        struct scsi_lun lun;
        int tm_tag = snic_cmd_tag(sc) | rqi->tm_tag;
        int ret = 0;

        SNIC_BUG_ON(!rqi);
        SNIC_BUG_ON(!rqi->tm_tag);

        /* fill in lun info */
        int_to_scsilun(sc->device->lun, &lun);

        /* Initialize snic_host_req: itmf */
        snic_itmf_init(tmreq,
                       tm_tag,
                       snic->config.hid,
                       (ulong) rqi,
                       0 /* flags */,
                       req_id, /* Command to be aborted. */
                       rqi->tgt_id,
                       lun.scsi_lun,
                       tmf);

        /*
         * In case of multiple aborts on same cmd,
         * use try_wait_for_completion and completion_done() to check
         * whether it queues aborts even after completion of abort issued
         * prior.SNIC_BUG_ON(completion_done(&rqi->done));
         */

        ret = snic_queue_wq_desc(snic, tmreq, sizeof(*tmreq));
        if (ret)
                SNIC_HOST_ERR(snic->shost,
                              "qitmf:Queuing ITMF(%d) Req sc %p, rqi %p, req_id %d tag %d Failed, ret = %d\n",
                              tmf, sc, rqi, req_id, snic_cmd_tag(sc), ret);
        else
                SNIC_SCSI_DBG(snic->shost,
                              "qitmf:Queuing ITMF(%d) Req sc %p, rqi %p, req_id %d, tag %d (req_id)- Success.",
                              tmf, sc, rqi, req_id, snic_cmd_tag(sc));

        return ret;
} /* end of snic_queue_itmf_req */

static int
snic_issue_tm_req(struct snic *snic,
                    struct snic_req_info *rqi,
                    struct scsi_cmnd *sc,
                    int tmf)
{
        struct snic_host_req *tmreq = NULL;
        int req_id = 0, tag = snic_cmd_tag(sc);
        int ret = 0;

        if (snic_get_state(snic) == SNIC_FWRESET)
                return -EBUSY;

        atomic_inc(&snic->ios_inflight);

        SNIC_SCSI_DBG(snic->shost,
                      "issu_tmreq: Task mgmt req %d. rqi %p w/ tag %x\n",
                      tmf, rqi, tag);


        if (tmf == SNIC_ITMF_LUN_RESET) {
                tmreq = snic_dr_req_init(snic, rqi);
                req_id = SCSI_NO_TAG;
        } else {
                tmreq = snic_abort_req_init(snic, rqi);
                req_id = tag;
        }

        if (!tmreq) {
                ret = -ENOMEM;

                goto tmreq_err;
        }

        ret = snic_queue_itmf_req(snic, tmreq, sc, tmf, req_id);

tmreq_err:
        if (ret) {
                SNIC_HOST_ERR(snic->shost,
                              "issu_tmreq: Queueing ITMF(%d) Req, sc %p rqi %p req_id %d tag %x fails err = %d\n",
                              tmf, sc, rqi, req_id, tag, ret);
        } else {
                SNIC_SCSI_DBG(snic->shost,
                              "issu_tmreq: Queueing ITMF(%d) Req, sc %p, rqi %p, req_id %d tag %x - Success.\n",
                              tmf, sc, rqi, req_id, tag);
        }

        atomic_dec(&snic->ios_inflight);

        return ret;
}

/*
 * snic_queue_abort_req : Queues abort req to WQ
 */
static int
snic_queue_abort_req(struct snic *snic,
                     struct snic_req_info *rqi,
                     struct scsi_cmnd *sc,
                     int tmf)
{
        SNIC_SCSI_DBG(snic->shost, "q_abtreq: sc %p, rqi %p, tag %x, tmf %d\n",
                      sc, rqi, snic_cmd_tag(sc), tmf);

        /* Add special tag for abort */
        rqi->tm_tag |= SNIC_TAG_ABORT;

        return snic_issue_tm_req(snic, rqi, sc, tmf);
}

/*
 * snic_abort_finish : called by snic_abort_cmd on queuing abort successfully.
 */
static int
snic_abort_finish(struct snic *snic, struct scsi_cmnd *sc)
{
        struct snic_req_info *rqi = NULL;
        spinlock_t *io_lock = NULL;
        unsigned long flags;
        int ret = 0, tag = snic_cmd_tag(sc);

        io_lock = snic_io_lock_hash(snic, sc);
        spin_lock_irqsave(io_lock, flags);
        rqi = (struct snic_req_info *) CMD_SP(sc);
        if (!rqi) {
                atomic64_inc(&snic->s_stats.io.req_null);
                CMD_FLAGS(sc) |= SNIC_IO_ABTS_TERM_REQ_NULL;

                SNIC_SCSI_DBG(snic->shost,
                              "abt_fini:req info is null tag 0x%x, sc 0x%p flags 0x%llx\n",
                              tag, sc, CMD_FLAGS(sc));
                ret = FAILED;

                goto abort_fail;
        }

        rqi->abts_done = NULL;

        ret = FAILED;

        /* Check the abort status. */
        switch (CMD_ABTS_STATUS(sc)) {
        case SNIC_INVALID_CODE:
                /* Firmware didn't complete abort req, timedout */
                CMD_FLAGS(sc) |= SNIC_IO_ABTS_TIMEDOUT;
                atomic64_inc(&snic->s_stats.abts.drv_tmo);
                SNIC_SCSI_DBG(snic->shost,
                              "abt_fini:sc %p Tag %x Driver Timeout.flags 0x%llx\n",
                              sc, snic_cmd_tag(sc), CMD_FLAGS(sc));
                /* do not release snic request in timedout case */
                rqi = NULL;

                goto abort_fail;

        case SNIC_STAT_IO_SUCCESS:
        case SNIC_STAT_IO_NOT_FOUND:
                ret = SUCCESS;
                /*
                 * If abort path doesn't call scsi_done(),
                 * the # IO timeouts == 2, will cause the LUN offline.
                 * Call scsi_done to complete the IO.
                 */
                sc->result = (DID_ERROR << 16);
                scsi_done(sc);
                break;

        default:
                /* Firmware completed abort with error */
                ret = FAILED;
                rqi = NULL;
                break;
        }

        CMD_SP(sc) = NULL;
        SNIC_HOST_INFO(snic->shost,
                       "abt_fini: Tag %x, Cmpl Status %s flags 0x%llx\n",
                       tag, snic_io_status_to_str(CMD_ABTS_STATUS(sc)),
                       CMD_FLAGS(sc));

abort_fail:
        spin_unlock_irqrestore(io_lock, flags);
        if (rqi)
                snic_release_req_buf(snic, rqi, sc);

        return ret;
} /* end of snic_abort_finish */

/*
 * snic_send_abort_and_wait : Issues Abort, and Waits
 */
static int
snic_send_abort_and_wait(struct snic *snic, struct scsi_cmnd *sc)
{
        struct snic_req_info *rqi = NULL;
        enum snic_ioreq_state sv_state;
        struct snic_tgt *tgt = NULL;
        spinlock_t *io_lock = NULL;
        DECLARE_COMPLETION_ONSTACK(tm_done);
        unsigned long flags;
        int ret = 0, tmf = 0, tag = snic_cmd_tag(sc);

        tgt = starget_to_tgt(scsi_target(sc->device));
        if ((snic_tgt_chkready(tgt) != 0) && (tgt->tdata.typ == SNIC_TGT_SAN))
                tmf = SNIC_ITMF_ABTS_TASK_TERM;
        else
                tmf = SNIC_ITMF_ABTS_TASK;

        /* stats */

        io_lock = snic_io_lock_hash(snic, sc);

        /*
         * Avoid a race between SCSI issuing the abort and the device
         * completing the command.
         *
         * If the command is already completed by fw_cmpl code,
         * we just return SUCCESS from here. This means that the abort
         * succeeded. In the SCSI ML, since the timeout for command has
         * happend, the completion wont actually complete the command
         * and it will be considered as an aborted command
         *
         * The CMD_SP will not be cleared except while holding io_lock
         */
        spin_lock_irqsave(io_lock, flags);
        rqi = (struct snic_req_info *) CMD_SP(sc);
        if (!rqi) {
                spin_unlock_irqrestore(io_lock, flags);

                SNIC_HOST_ERR(snic->shost,
                              "abt_cmd: rqi is null. Tag %d flags 0x%llx\n",
                              tag, CMD_FLAGS(sc));

                ret = SUCCESS;

                goto send_abts_end;
        }

        rqi->abts_done = &tm_done;
        if (CMD_STATE(sc) == SNIC_IOREQ_ABTS_PENDING) {
                spin_unlock_irqrestore(io_lock, flags);

                ret = 0;
                goto abts_pending;
        }
        SNIC_BUG_ON(!rqi->abts_done);

        /* Save Command State, should be restored on failed to Queue. */
        sv_state = CMD_STATE(sc);

        /*
         * Command is still pending, need to abort it
         * If the fw completes the command after this point,
         * the completion won't be done till mid-layer, since abot
         * has already started.
         */
        CMD_STATE(sc) = SNIC_IOREQ_ABTS_PENDING;
        CMD_ABTS_STATUS(sc) = SNIC_INVALID_CODE;

        SNIC_SCSI_DBG(snic->shost, "send_abt_cmd: TAG 0x%x\n", tag);

        spin_unlock_irqrestore(io_lock, flags);

        /* Now Queue the abort command to firmware */
        ret = snic_queue_abort_req(snic, rqi, sc, tmf);
        if (ret) {
                atomic64_inc(&snic->s_stats.abts.q_fail);
                SNIC_HOST_ERR(snic->shost,
                              "send_abt_cmd: IO w/ Tag 0x%x fail w/ err %d flags 0x%llx\n",
                              tag, ret, CMD_FLAGS(sc));

                spin_lock_irqsave(io_lock, flags);
                /* Restore Command's previous state */
                CMD_STATE(sc) = sv_state;
                rqi = (struct snic_req_info *) CMD_SP(sc);
                if (rqi)
                        rqi->abts_done = NULL;
                spin_unlock_irqrestore(io_lock, flags);
                ret = FAILED;

                goto send_abts_end;
        }

        spin_lock_irqsave(io_lock, flags);
        if (tmf == SNIC_ITMF_ABTS_TASK) {
                CMD_FLAGS(sc) |= SNIC_IO_ABTS_ISSUED;
                atomic64_inc(&snic->s_stats.abts.num);
        } else {
                /* term stats */
                CMD_FLAGS(sc) |= SNIC_IO_TERM_ISSUED;
        }
        spin_unlock_irqrestore(io_lock, flags);

        SNIC_SCSI_DBG(snic->shost,
                      "send_abt_cmd: sc %p Tag %x flags 0x%llx\n",
                      sc, tag, CMD_FLAGS(sc));


        ret = 0;

abts_pending:
        /*
         * Queued an abort IO, wait for its completion.
         * Once the fw completes the abort command, it will
         * wakeup this thread.
         */
        wait_for_completion_timeout(&tm_done, SNIC_ABTS_TIMEOUT);

send_abts_end:
        return ret;
} /* end of snic_send_abort_and_wait */

/*
 * This function is exported to SCSI for sending abort cmnds.
 * A SCSI IO is represent by snic_ioreq in the driver.
 * The snic_ioreq is linked to the SCSI Cmd, thus a link with the ULP'S IO
 */
int
snic_abort_cmd(struct scsi_cmnd *sc)
{
        struct snic *snic = shost_priv(sc->device->host);
        int ret = SUCCESS, tag = snic_cmd_tag(sc);
        u32 start_time = jiffies;

        SNIC_SCSI_DBG(snic->shost, "abt_cmd:sc %p :0x%x :req = %p :tag = %d\n",
                       sc, sc->cmnd[0], scsi_cmd_to_rq(sc), tag);

        if (unlikely(snic_get_state(snic) != SNIC_ONLINE)) {
                SNIC_HOST_ERR(snic->shost,
                              "abt_cmd: tag %x Parent Devs are not rdy\n",
                              tag);
                ret = FAST_IO_FAIL;

                goto abort_end;
        }


        ret = snic_send_abort_and_wait(snic, sc);
        if (ret)
                goto abort_end;

        ret = snic_abort_finish(snic, sc);

abort_end:
        SNIC_TRC(snic->shost->host_no, tag, (ulong) sc,
                 jiffies_to_msecs(jiffies - start_time), 0,
                 SNIC_TRC_CMD(sc), SNIC_TRC_CMD_STATE_FLAGS(sc));

        SNIC_SCSI_DBG(snic->shost,
                      "abts: Abort Req Status = %s\n",
                      (ret == SUCCESS) ? "SUCCESS" :
                       ((ret == FAST_IO_FAIL) ? "FAST_IO_FAIL" : "FAILED"));

        return ret;
}



static int
snic_is_abts_pending(struct snic *snic, struct scsi_cmnd *lr_sc)
{
        struct snic_req_info *rqi = NULL;
        struct scsi_cmnd *sc = NULL;
        struct scsi_device *lr_sdev = NULL;
        spinlock_t *io_lock = NULL;
        u32 tag;
        unsigned long flags;

        if (lr_sc)
                lr_sdev = lr_sc->device;

        /* walk through the tag map, an dcheck if IOs are still pending in fw*/
        for (tag = 0; tag < snic->max_tag_id; tag++) {
                io_lock = snic_io_lock_tag(snic, tag);

                spin_lock_irqsave(io_lock, flags);
                sc = scsi_host_find_tag(snic->shost, tag);

                if (!sc || (lr_sc && (sc->device != lr_sdev || sc == lr_sc))) {
                        spin_unlock_irqrestore(io_lock, flags);

                        continue;
                }

                rqi = (struct snic_req_info *) CMD_SP(sc);
                if (!rqi) {
                        spin_unlock_irqrestore(io_lock, flags);

                        continue;
                }

                /*
                 * Found IO that is still pending w/ firmware and belongs to
                 * the LUN that is under reset, if lr_sc != NULL
                 */
                SNIC_SCSI_DBG(snic->shost, "Found IO in %s on LUN\n",
                              snic_ioreq_state_to_str(CMD_STATE(sc)));

                if (CMD_STATE(sc) == SNIC_IOREQ_ABTS_PENDING) {
                        spin_unlock_irqrestore(io_lock, flags);

                        return 1;
                }

                spin_unlock_irqrestore(io_lock, flags);
        }

        return 0;
} /* end of snic_is_abts_pending */

static int
snic_dr_clean_single_req(struct snic *snic,
                         u32 tag,
                         struct scsi_device *lr_sdev)
{
        struct snic_req_info *rqi = NULL;
        struct snic_tgt *tgt = NULL;
        struct scsi_cmnd *sc = NULL;
        spinlock_t *io_lock = NULL;
        u32 sv_state = 0, tmf = 0;
        DECLARE_COMPLETION_ONSTACK(tm_done);
        unsigned long flags;
        int ret = 0;

        io_lock = snic_io_lock_tag(snic, tag);
        spin_lock_irqsave(io_lock, flags);
        sc = scsi_host_find_tag(snic->shost, tag);

        /* Ignore Cmd that don't belong to Lun Reset device */
        if (!sc || sc->device != lr_sdev)
                goto skip_clean;

        rqi = (struct snic_req_info *) CMD_SP(sc);

        if (!rqi)
                goto skip_clean;


        if (CMD_STATE(sc) == SNIC_IOREQ_ABTS_PENDING)
                goto skip_clean;


        if ((CMD_FLAGS(sc) & SNIC_DEVICE_RESET) &&
                        (!(CMD_FLAGS(sc) & SNIC_DEV_RST_ISSUED))) {

                SNIC_SCSI_DBG(snic->shost,
                              "clean_single_req: devrst is not pending sc 0x%p\n",
                              sc);

                goto skip_clean;
        }

        SNIC_SCSI_DBG(snic->shost,
                "clean_single_req: Found IO in %s on lun\n",
                snic_ioreq_state_to_str(CMD_STATE(sc)));

        /* Save Command State */
        sv_state = CMD_STATE(sc);

        /*
         * Any pending IO issued prior to reset is expected to be
         * in abts pending state, if not we need to set SNIC_IOREQ_ABTS_PENDING
         * to indicate the IO is abort pending.
         * When IO is completed, the IO will be handed over and handled
         * in this function.
         */

        CMD_STATE(sc) = SNIC_IOREQ_ABTS_PENDING;
        SNIC_BUG_ON(rqi->abts_done);

        if (CMD_FLAGS(sc) & SNIC_DEVICE_RESET) {
                rqi->tm_tag = SNIC_TAG_DEV_RST;

                SNIC_SCSI_DBG(snic->shost,
                              "clean_single_req:devrst sc 0x%p\n", sc);
        }

        CMD_ABTS_STATUS(sc) = SNIC_INVALID_CODE;
        rqi->abts_done = &tm_done;
        spin_unlock_irqrestore(io_lock, flags);

        tgt = starget_to_tgt(scsi_target(sc->device));
        if ((snic_tgt_chkready(tgt) != 0) && (tgt->tdata.typ == SNIC_TGT_SAN))
                tmf = SNIC_ITMF_ABTS_TASK_TERM;
        else
                tmf = SNIC_ITMF_ABTS_TASK;

        /* Now queue the abort command to firmware */
        ret = snic_queue_abort_req(snic, rqi, sc, tmf);
        if (ret) {
                SNIC_HOST_ERR(snic->shost,
                              "clean_single_req_err:sc %p, tag %d abt failed. tm_tag %d flags 0x%llx\n",
                              sc, tag, rqi->tm_tag, CMD_FLAGS(sc));

                spin_lock_irqsave(io_lock, flags);
                rqi = (struct snic_req_info *) CMD_SP(sc);
                if (rqi)
                        rqi->abts_done = NULL;

                /* Restore Command State */
                if (CMD_STATE(sc) == SNIC_IOREQ_ABTS_PENDING)
                        CMD_STATE(sc) = sv_state;

                ret = 1;
                goto skip_clean;
        }

        spin_lock_irqsave(io_lock, flags);
        if (CMD_FLAGS(sc) & SNIC_DEVICE_RESET)
                CMD_FLAGS(sc) |= SNIC_DEV_RST_TERM_ISSUED;

        CMD_FLAGS(sc) |= SNIC_IO_INTERNAL_TERM_ISSUED;
        spin_unlock_irqrestore(io_lock, flags);

        wait_for_completion_timeout(&tm_done, SNIC_ABTS_TIMEOUT);

        /* Recheck cmd state to check if it now aborted. */
        spin_lock_irqsave(io_lock, flags);
        rqi = (struct snic_req_info *) CMD_SP(sc);
        if (!rqi) {
                CMD_FLAGS(sc) |= SNIC_IO_ABTS_TERM_REQ_NULL;
                goto skip_clean;
        }
        rqi->abts_done = NULL;

        /* if abort is still pending w/ fw, fail */
        if (CMD_ABTS_STATUS(sc) == SNIC_INVALID_CODE) {
                SNIC_HOST_ERR(snic->shost,
                              "clean_single_req_err:sc %p tag %d abt still pending w/ fw, tm_tag %d flags 0x%llx\n",
                              sc, tag, rqi->tm_tag, CMD_FLAGS(sc));

                CMD_FLAGS(sc) |= SNIC_IO_ABTS_TERM_DONE;
                ret = 1;

                goto skip_clean;
        }

        CMD_STATE(sc) = SNIC_IOREQ_ABTS_COMPLETE;
        CMD_SP(sc) = NULL;
        spin_unlock_irqrestore(io_lock, flags);

        snic_release_req_buf(snic, rqi, sc);

        sc->result = (DID_ERROR << 16);
        scsi_done(sc);

        ret = 0;

        return ret;

skip_clean:
        spin_unlock_irqrestore(io_lock, flags);

        return ret;
} /* end of snic_dr_clean_single_req */

static int
snic_dr_clean_pending_req(struct snic *snic, struct scsi_cmnd *lr_sc)
{
        struct scsi_device *lr_sdev = lr_sc->device;
        u32 tag = 0;
        int ret;

        for (tag = 0; tag < snic->max_tag_id; tag++) {
                if (tag == snic_cmd_tag(lr_sc))
                        continue;

                ret = snic_dr_clean_single_req(snic, tag, lr_sdev);
                if (ret) {
                        SNIC_HOST_ERR(snic->shost, "clean_err:tag = %d\n", tag);
                        goto clean_err;
                }
        }

        schedule_timeout(msecs_to_jiffies(100));

        /* Walk through all the cmds and check abts status. */
        if (snic_is_abts_pending(snic, lr_sc))
                goto clean_err;

        SNIC_SCSI_DBG(snic->shost, "clean_pending_req: Success.\n");

        return 0;

clean_err:
        SNIC_HOST_ERR(snic->shost,
                      "Failed to Clean Pending IOs on %s device.\n",
                      dev_name(&lr_sdev->sdev_gendev));

        return FAILED;

} /* end of snic_dr_clean_pending_req */

/*
 * snic_dr_finish : Called by snic_device_reset
 */
static int
snic_dr_finish(struct snic *snic, struct scsi_cmnd *sc)
{
        struct snic_req_info *rqi = NULL;
        spinlock_t *io_lock = NULL;
        unsigned long flags;
        int lr_res = 0;
        int ret = FAILED;

        io_lock = snic_io_lock_hash(snic, sc);
        spin_lock_irqsave(io_lock, flags);
        rqi = (struct snic_req_info *) CMD_SP(sc);
        if (!rqi) {
                spin_unlock_irqrestore(io_lock, flags);
                SNIC_SCSI_DBG(snic->shost,
                              "dr_fini: rqi is null tag 0x%x sc 0x%p flags 0x%llx\n",
                              snic_cmd_tag(sc), sc, CMD_FLAGS(sc));

                ret = FAILED;
                goto dr_fini_end;
        }

        rqi->dr_done = NULL;

        lr_res = CMD_LR_STATUS(sc);

        switch (lr_res) {
        case SNIC_INVALID_CODE:
                /* stats */
                SNIC_SCSI_DBG(snic->shost,
                              "dr_fini: Tag %x Dev Reset Timedout. flags 0x%llx\n",
                              snic_cmd_tag(sc), CMD_FLAGS(sc));

                CMD_FLAGS(sc) |= SNIC_DEV_RST_TIMEDOUT;
                ret = FAILED;

                goto dr_failed;

        case SNIC_STAT_IO_SUCCESS:
                SNIC_SCSI_DBG(snic->shost,
                              "dr_fini: Tag %x Dev Reset cmpl\n",
                              snic_cmd_tag(sc));
                ret = 0;
                break;

        default:
                SNIC_HOST_ERR(snic->shost,
                              "dr_fini:Device Reset completed& failed.Tag = %x lr_status %s flags 0x%llx\n",
                              snic_cmd_tag(sc),
                              snic_io_status_to_str(lr_res), CMD_FLAGS(sc));
                ret = FAILED;
                goto dr_failed;
        }
        spin_unlock_irqrestore(io_lock, flags);

        /*
         * Cleanup any IOs on this LUN that have still not completed.
         * If any of these fail, then LUN Reset fails.
         * Cleanup cleans all commands on this LUN except
         * the lun reset command. If all cmds get cleaned, the LUN Reset
         * succeeds.
         */

        ret = snic_dr_clean_pending_req(snic, sc);
        if (ret) {
                spin_lock_irqsave(io_lock, flags);
                SNIC_SCSI_DBG(snic->shost,
                              "dr_fini: Device Reset Failed since could not abort all IOs. Tag = %x.\n",
                              snic_cmd_tag(sc));
                rqi = (struct snic_req_info *) CMD_SP(sc);

                goto dr_failed;
        } else {
                /* Cleanup LUN Reset Command */
                spin_lock_irqsave(io_lock, flags);
                rqi = (struct snic_req_info *) CMD_SP(sc);
                if (rqi)
                        ret = SUCCESS; /* Completed Successfully */
                else
                        ret = FAILED;
        }

dr_failed:
        lockdep_assert_held(io_lock);
        if (rqi)
                CMD_SP(sc) = NULL;
        spin_unlock_irqrestore(io_lock, flags);

        if (rqi)
                snic_release_req_buf(snic, rqi, sc);

dr_fini_end:
        return ret;
} /* end of snic_dr_finish */

static int
snic_queue_dr_req(struct snic *snic,
                  struct snic_req_info *rqi,
                  struct scsi_cmnd *sc)
{
        /* Add special tag for device reset */
        rqi->tm_tag |= SNIC_TAG_DEV_RST;

        return snic_issue_tm_req(snic, rqi, sc, SNIC_ITMF_LUN_RESET);
}

static int
snic_send_dr_and_wait(struct snic *snic, struct scsi_cmnd *sc)
{
        struct snic_req_info *rqi = NULL;
        enum snic_ioreq_state sv_state;
        spinlock_t *io_lock = NULL;
        unsigned long flags;
        DECLARE_COMPLETION_ONSTACK(tm_done);
        int ret = FAILED, tag = snic_cmd_tag(sc);

        io_lock = snic_io_lock_hash(snic, sc);
        spin_lock_irqsave(io_lock, flags);
        CMD_FLAGS(sc) |= SNIC_DEVICE_RESET;
        rqi = (struct snic_req_info *) CMD_SP(sc);
        if (!rqi) {
                SNIC_HOST_ERR(snic->shost,
                              "send_dr: rqi is null, Tag 0x%x flags 0x%llx\n",
                              tag, CMD_FLAGS(sc));
                spin_unlock_irqrestore(io_lock, flags);

                ret = FAILED;
                goto send_dr_end;
        }

        /* Save Command state to restore in case Queuing failed. */
        sv_state = CMD_STATE(sc);

        CMD_STATE(sc) = SNIC_IOREQ_LR_PENDING;
        CMD_LR_STATUS(sc) = SNIC_INVALID_CODE;

        SNIC_SCSI_DBG(snic->shost, "dr: TAG = %x\n", tag);

        rqi->dr_done = &tm_done;
        SNIC_BUG_ON(!rqi->dr_done);

        spin_unlock_irqrestore(io_lock, flags);
        /*
         * The Command state is changed to IOREQ_PENDING,
         * in this case, if the command is completed, the icmnd_cmpl will
         * mark the cmd as completed.
         * This logic still makes LUN Reset is inevitable.
         */

        ret = snic_queue_dr_req(snic, rqi, sc);
        if (ret) {
                SNIC_HOST_ERR(snic->shost,
                              "send_dr: IO w/ Tag 0x%x Failed err = %d. flags 0x%llx\n",
                              tag, ret, CMD_FLAGS(sc));

                spin_lock_irqsave(io_lock, flags);
                /* Restore State */
                CMD_STATE(sc) = sv_state;
                rqi = (struct snic_req_info *) CMD_SP(sc);
                if (rqi)
                        rqi->dr_done = NULL;
                /* rqi is freed in caller. */
                spin_unlock_irqrestore(io_lock, flags);
                ret = FAILED;

                goto send_dr_end;
        }

        spin_lock_irqsave(io_lock, flags);
        CMD_FLAGS(sc) |= SNIC_DEV_RST_ISSUED;
        spin_unlock_irqrestore(io_lock, flags);

        ret = 0;

        wait_for_completion_timeout(&tm_done, SNIC_LUN_RESET_TIMEOUT);

send_dr_end:
        return ret;
}

/*
 * auxillary funciton to check lun reset op is supported or not
 * Not supported if returns 0
 */
static int
snic_dev_reset_supported(struct scsi_device *sdev)
{
        struct snic_tgt *tgt = starget_to_tgt(scsi_target(sdev));

        if (tgt->tdata.typ == SNIC_TGT_DAS)
                return 0;

        return 1;
}

static void
snic_unlink_and_release_req(struct snic *snic, struct scsi_cmnd *sc, int flag)
{
        struct snic_req_info *rqi = NULL;
        spinlock_t *io_lock = NULL;
        unsigned long flags;
        u32 start_time = jiffies;

        io_lock = snic_io_lock_hash(snic, sc);
        spin_lock_irqsave(io_lock, flags);
        rqi = (struct snic_req_info *) CMD_SP(sc);
        if (rqi) {
                start_time = rqi->start_time;
                CMD_SP(sc) = NULL;
        }

        CMD_FLAGS(sc) |= flag;
        spin_unlock_irqrestore(io_lock, flags);

        if (rqi)
                snic_release_req_buf(snic, rqi, sc);

        SNIC_TRC(snic->shost->host_no, snic_cmd_tag(sc), (ulong) sc,
                 jiffies_to_msecs(jiffies - start_time), (ulong) rqi,
                 SNIC_TRC_CMD(sc), SNIC_TRC_CMD_STATE_FLAGS(sc));
}

/*
 * SCSI Eh thread issues a LUN Reset when one or more commands on a LUN
 * fail to get aborted. It calls driver's eh_device_reset with a SCSI
 * command on the LUN.
 */
int
snic_device_reset(struct scsi_cmnd *sc)
{
        struct Scsi_Host *shost = sc->device->host;
        struct snic *snic = shost_priv(shost);
        struct snic_req_info *rqi = NULL;
        int tag = snic_cmd_tag(sc);
        int start_time = jiffies;
        int ret = FAILED;
        int dr_supp = 0;

        SNIC_SCSI_DBG(shost, "dev_reset:sc %p :0x%x :req = %p :tag = %d\n",
                      sc, sc->cmnd[0], scsi_cmd_to_rq(sc),
                      snic_cmd_tag(sc));
        dr_supp = snic_dev_reset_supported(sc->device);
        if (!dr_supp) {
                /* device reset op is not supported */
                SNIC_HOST_INFO(shost, "LUN Reset Op not supported.\n");
                snic_unlink_and_release_req(snic, sc, SNIC_DEV_RST_NOTSUP);

                goto dev_rst_end;
        }

        if (unlikely(snic_get_state(snic) != SNIC_ONLINE)) {
                snic_unlink_and_release_req(snic, sc, 0);
                SNIC_HOST_ERR(shost, "Devrst: Parent Devs are not online.\n");

                goto dev_rst_end;
        }

        /* There is no tag when lun reset is issue through ioctl. */
        if (unlikely(tag <= SNIC_NO_TAG)) {
                SNIC_HOST_INFO(snic->shost,
                               "Devrst: LUN Reset Recvd thru IOCTL.\n");

                rqi = snic_req_init(snic, 0);
                if (!rqi)
                        goto dev_rst_end;

                memset(scsi_cmd_priv(sc), 0,
                        sizeof(struct snic_internal_io_state));
                CMD_SP(sc) = (char *)rqi;
                CMD_FLAGS(sc) = SNIC_NO_FLAGS;

                /* Add special tag for dr coming from user spc */
                rqi->tm_tag = SNIC_TAG_IOCTL_DEV_RST;
                rqi->sc = sc;
        }

        ret = snic_send_dr_and_wait(snic, sc);
        if (ret) {
                SNIC_HOST_ERR(snic->shost,
                              "Devrst: IO w/ Tag %x Failed w/ err = %d\n",
                              tag, ret);

                snic_unlink_and_release_req(snic, sc, 0);

                goto dev_rst_end;
        }

        ret = snic_dr_finish(snic, sc);

dev_rst_end:
        SNIC_TRC(snic->shost->host_no, tag, (ulong) sc,
                 jiffies_to_msecs(jiffies - start_time),
                 0, SNIC_TRC_CMD(sc), SNIC_TRC_CMD_STATE_FLAGS(sc));

        SNIC_SCSI_DBG(snic->shost,
                      "Devrst: Returning from Device Reset : %s\n",
                      (ret == SUCCESS) ? "SUCCESS" : "FAILED");

        return ret;
} /* end of snic_device_reset */

/*
 * SCSI Error handling calls driver's eh_host_reset if all prior
 * error handling levels return FAILED.
 *
 * Host Reset is the highest level of error recovery. If this fails, then
 * host is offlined by SCSI.
 */
/*
 * snic_issue_hba_reset : Queues FW Reset Request.
 */
static int
snic_issue_hba_reset(struct snic *snic, struct scsi_cmnd *sc)
{
        struct snic_req_info *rqi = NULL;
        struct snic_host_req *req = NULL;
        spinlock_t *io_lock = NULL;
        DECLARE_COMPLETION_ONSTACK(wait);
        unsigned long flags;
        int ret = -ENOMEM;

        rqi = snic_req_init(snic, 0);
        if (!rqi) {
                ret = -ENOMEM;

                goto hba_rst_end;
        }

        if (snic_cmd_tag(sc) == SCSI_NO_TAG) {
                memset(scsi_cmd_priv(sc), 0,
                        sizeof(struct snic_internal_io_state));
                SNIC_HOST_INFO(snic->shost, "issu_hr:Host reset thru ioctl.\n");
                rqi->sc = sc;
        }

        req = rqi_to_req(rqi);

        io_lock = snic_io_lock_hash(snic, sc);
        spin_lock_irqsave(io_lock, flags);
        SNIC_BUG_ON(CMD_SP(sc) != NULL);
        CMD_STATE(sc) = SNIC_IOREQ_PENDING;
        CMD_SP(sc) = (char *) rqi;
        CMD_FLAGS(sc) |= SNIC_IO_INITIALIZED;
        snic->remove_wait = &wait;
        spin_unlock_irqrestore(io_lock, flags);

        /* Initialize Request */
        snic_io_hdr_enc(&req->hdr, SNIC_REQ_HBA_RESET, 0, snic_cmd_tag(sc),
                        snic->config.hid, 0, (ulong) rqi);

        req->u.reset.flags = 0;

        ret = snic_queue_wq_desc(snic, req, sizeof(*req));
        if (ret) {
                SNIC_HOST_ERR(snic->shost,
                              "issu_hr:Queuing HBA Reset Failed. w err %d\n",
                              ret);

                goto hba_rst_err;
        }

        spin_lock_irqsave(io_lock, flags);
        CMD_FLAGS(sc) |= SNIC_HOST_RESET_ISSUED;
        spin_unlock_irqrestore(io_lock, flags);
        atomic64_inc(&snic->s_stats.reset.hba_resets);
        SNIC_HOST_INFO(snic->shost, "Queued HBA Reset Successfully.\n");

        wait_for_completion_timeout(snic->remove_wait,
                                    SNIC_HOST_RESET_TIMEOUT);

        if (snic_get_state(snic) == SNIC_FWRESET) {
                SNIC_HOST_ERR(snic->shost, "reset_cmpl: Reset Timedout.\n");
                ret = -ETIMEDOUT;

                goto hba_rst_err;
        }

        spin_lock_irqsave(io_lock, flags);
        snic->remove_wait = NULL;
        rqi = (struct snic_req_info *) CMD_SP(sc);
        CMD_SP(sc) = NULL;
        spin_unlock_irqrestore(io_lock, flags);

        if (rqi)
                snic_req_free(snic, rqi);

        ret = 0;

        return ret;

hba_rst_err:
        spin_lock_irqsave(io_lock, flags);
        snic->remove_wait = NULL;
        rqi = (struct snic_req_info *) CMD_SP(sc);
        CMD_SP(sc) = NULL;
        spin_unlock_irqrestore(io_lock, flags);

        if (rqi)
                snic_req_free(snic, rqi);

hba_rst_end:
        SNIC_HOST_ERR(snic->shost,
                      "reset:HBA Reset Failed w/ err = %d.\n",
                      ret);

        return ret;
} /* end of snic_issue_hba_reset */

int
snic_reset(struct Scsi_Host *shost, struct scsi_cmnd *sc)
{
        struct snic *snic = shost_priv(shost);
        enum snic_state sv_state;
        unsigned long flags;
        int ret = FAILED;

        /* Set snic state as SNIC_FWRESET*/
        sv_state = snic_get_state(snic);

        spin_lock_irqsave(&snic->snic_lock, flags);
        if (snic_get_state(snic) == SNIC_FWRESET) {
                spin_unlock_irqrestore(&snic->snic_lock, flags);
                SNIC_HOST_INFO(shost, "reset:prev reset is in progress\n");

                msleep(SNIC_HOST_RESET_TIMEOUT);
                ret = SUCCESS;

                goto reset_end;
        }

        snic_set_state(snic, SNIC_FWRESET);
        spin_unlock_irqrestore(&snic->snic_lock, flags);


        /* Wait for all the IOs that are entered in Qcmd */
        while (atomic_read(&snic->ios_inflight))
                schedule_timeout(msecs_to_jiffies(1));

        ret = snic_issue_hba_reset(snic, sc);
        if (ret) {
                SNIC_HOST_ERR(shost,
                              "reset:Host Reset Failed w/ err %d.\n",
                              ret);
                spin_lock_irqsave(&snic->snic_lock, flags);
                snic_set_state(snic, sv_state);
                spin_unlock_irqrestore(&snic->snic_lock, flags);
                atomic64_inc(&snic->s_stats.reset.hba_reset_fail);
                ret = FAILED;

                goto reset_end;
        }

        ret = SUCCESS;

reset_end:
        return ret;
} /* end of snic_reset */

/*
 * SCSI Error handling calls driver's eh_host_reset if all prior
 * error handling levels return FAILED.
 *
 * Host Reset is the highest level of error recovery. If this fails, then
 * host is offlined by SCSI.
 */
int
snic_host_reset(struct scsi_cmnd *sc)
{
        struct Scsi_Host *shost = sc->device->host;
        u32 start_time  = jiffies;
        int ret;

        SNIC_SCSI_DBG(shost,
                      "host reset:sc %p sc_cmd 0x%x req %p tag %d flags 0x%llx\n",
                      sc, sc->cmnd[0], scsi_cmd_to_rq(sc),
                      snic_cmd_tag(sc), CMD_FLAGS(sc));

        ret = snic_reset(shost, sc);

        SNIC_TRC(shost->host_no, snic_cmd_tag(sc), (ulong) sc,
                 jiffies_to_msecs(jiffies - start_time),
                 0, SNIC_TRC_CMD(sc), SNIC_TRC_CMD_STATE_FLAGS(sc));

        return ret;
} /* end of snic_host_reset */

/*
 * snic_cmpl_pending_tmreq : Caller should hold io_lock
 */
static void
snic_cmpl_pending_tmreq(struct snic *snic, struct scsi_cmnd *sc)
{
        struct snic_req_info *rqi = NULL;

        SNIC_SCSI_DBG(snic->shost,
                      "Completing Pending TM Req sc %p, state %s flags 0x%llx\n",
                      sc, snic_io_status_to_str(CMD_STATE(sc)), CMD_FLAGS(sc));

        /*
         * CASE : FW didn't post itmf completion due to PCIe Errors.
         * Marking the abort status as Success to call scsi completion
         * in snic_abort_finish()
         */
        CMD_ABTS_STATUS(sc) = SNIC_STAT_IO_SUCCESS;

        rqi = (struct snic_req_info *) CMD_SP(sc);
        if (!rqi)
                return;

        if (rqi->dr_done)
                complete(rqi->dr_done);
        else if (rqi->abts_done)
                complete(rqi->abts_done);
}

/*
 * snic_scsi_cleanup: Walks through tag map and releases the reqs
 */
static void
snic_scsi_cleanup(struct snic *snic, int ex_tag)
{
        struct snic_req_info *rqi = NULL;
        struct scsi_cmnd *sc = NULL;
        spinlock_t *io_lock = NULL;
        unsigned long flags;
        int tag;
        u64 st_time = 0;

        SNIC_SCSI_DBG(snic->shost, "sc_clean: scsi cleanup.\n");

        for (tag = 0; tag < snic->max_tag_id; tag++) {
                /* Skip ex_tag */
                if (tag == ex_tag)
                        continue;

                io_lock = snic_io_lock_tag(snic, tag);
                spin_lock_irqsave(io_lock, flags);
                sc = scsi_host_find_tag(snic->shost, tag);
                if (!sc) {
                        spin_unlock_irqrestore(io_lock, flags);

                        continue;
                }

                if (unlikely(snic_tmreq_pending(sc))) {
                        /*
                         * When FW Completes reset w/o sending completions
                         * for outstanding ios.
                         */
                        snic_cmpl_pending_tmreq(snic, sc);
                        spin_unlock_irqrestore(io_lock, flags);

                        continue;
                }

                rqi = (struct snic_req_info *) CMD_SP(sc);
                if (!rqi) {
                        spin_unlock_irqrestore(io_lock, flags);

                        goto cleanup;
                }

                SNIC_SCSI_DBG(snic->shost,
                              "sc_clean: sc %p, rqi %p, tag %d flags 0x%llx\n",
                              sc, rqi, tag, CMD_FLAGS(sc));

                CMD_SP(sc) = NULL;
                CMD_FLAGS(sc) |= SNIC_SCSI_CLEANUP;
                spin_unlock_irqrestore(io_lock, flags);
                st_time = rqi->start_time;

                SNIC_HOST_INFO(snic->shost,
                               "sc_clean: Releasing rqi %p : flags 0x%llx\n",
                               rqi, CMD_FLAGS(sc));

                snic_release_req_buf(snic, rqi, sc);

cleanup:
                sc->result = DID_TRANSPORT_DISRUPTED << 16;
                SNIC_HOST_INFO(snic->shost,
                               "sc_clean: DID_TRANSPORT_DISRUPTED for sc %p, Tag %d flags 0x%llx rqi %p duration %u msecs\n",
                               sc, scsi_cmd_to_rq(sc)->tag, CMD_FLAGS(sc), rqi,
                               jiffies_to_msecs(jiffies - st_time));

                /* Update IO stats */
                snic_stats_update_io_cmpl(&snic->s_stats);

                SNIC_TRC(snic->shost->host_no, tag, (ulong) sc,
                         jiffies_to_msecs(jiffies - st_time), 0,
                         SNIC_TRC_CMD(sc),
                         SNIC_TRC_CMD_STATE_FLAGS(sc));

                scsi_done(sc);
        }
} /* end of snic_scsi_cleanup */

void
snic_shutdown_scsi_cleanup(struct snic *snic)
{
        SNIC_HOST_INFO(snic->shost, "Shutdown time SCSI Cleanup.\n");

        snic_scsi_cleanup(snic, SCSI_NO_TAG);
} /* end of snic_shutdown_scsi_cleanup */

/*
 * snic_internal_abort_io
 * called by : snic_tgt_scsi_abort_io
 */
static int
snic_internal_abort_io(struct snic *snic, struct scsi_cmnd *sc, int tmf)
{
        struct snic_req_info *rqi = NULL;
        spinlock_t *io_lock = NULL;
        unsigned long flags;
        u32 sv_state = 0;
        int ret = 0;

        io_lock = snic_io_lock_hash(snic, sc);
        spin_lock_irqsave(io_lock, flags);
        rqi = (struct snic_req_info *) CMD_SP(sc);
        if (!rqi)
                goto skip_internal_abts;

        if (CMD_STATE(sc) == SNIC_IOREQ_ABTS_PENDING)
                goto skip_internal_abts;

        if ((CMD_FLAGS(sc) & SNIC_DEVICE_RESET) &&
                (!(CMD_FLAGS(sc) & SNIC_DEV_RST_ISSUED))) {

                SNIC_SCSI_DBG(snic->shost,
                              "internal_abts: dev rst not pending sc 0x%p\n",
                              sc);

                goto skip_internal_abts;
        }


        if (!(CMD_FLAGS(sc) & SNIC_IO_ISSUED)) {
                SNIC_SCSI_DBG(snic->shost,
                        "internal_abts: IO not yet issued sc 0x%p tag 0x%x flags 0x%llx state %d\n",
                        sc, snic_cmd_tag(sc), CMD_FLAGS(sc), CMD_STATE(sc));

                goto skip_internal_abts;
        }

        sv_state = CMD_STATE(sc);
        CMD_STATE(sc) = SNIC_IOREQ_ABTS_PENDING;
        CMD_ABTS_STATUS(sc) = SNIC_INVALID_CODE;
        CMD_FLAGS(sc) |= SNIC_IO_INTERNAL_TERM_PENDING;

        if (CMD_FLAGS(sc) & SNIC_DEVICE_RESET) {
                /* stats */
                rqi->tm_tag = SNIC_TAG_DEV_RST;
                SNIC_SCSI_DBG(snic->shost, "internal_abts:dev rst sc %p\n", sc);
        }

        SNIC_SCSI_DBG(snic->shost, "internal_abts: Issuing abts tag %x\n",
                      snic_cmd_tag(sc));
        SNIC_BUG_ON(rqi->abts_done);
        spin_unlock_irqrestore(io_lock, flags);

        ret = snic_queue_abort_req(snic, rqi, sc, tmf);
        if (ret) {
                SNIC_HOST_ERR(snic->shost,
                              "internal_abts: Tag = %x , Failed w/ err = %d\n",
                              snic_cmd_tag(sc), ret);

                spin_lock_irqsave(io_lock, flags);

                if (CMD_STATE(sc) == SNIC_IOREQ_ABTS_PENDING)
                        CMD_STATE(sc) = sv_state;

                goto skip_internal_abts;
        }

        spin_lock_irqsave(io_lock, flags);
        if (CMD_FLAGS(sc) & SNIC_DEVICE_RESET)
                CMD_FLAGS(sc) |= SNIC_DEV_RST_TERM_ISSUED;
        else
                CMD_FLAGS(sc) |= SNIC_IO_INTERNAL_TERM_ISSUED;

        ret = SUCCESS;

skip_internal_abts:
        lockdep_assert_held(io_lock);
        spin_unlock_irqrestore(io_lock, flags);

        return ret;
} /* end of snic_internal_abort_io */

/*
 * snic_tgt_scsi_abort_io : called by snic_tgt_del
 */
int
snic_tgt_scsi_abort_io(struct snic_tgt *tgt)
{
        struct snic *snic = NULL;
        struct scsi_cmnd *sc = NULL;
        struct snic_tgt *sc_tgt = NULL;
        spinlock_t *io_lock = NULL;
        unsigned long flags;
        int ret = 0, tag, abt_cnt = 0, tmf = 0;

        if (!tgt)
                return -1;

        snic = shost_priv(snic_tgt_to_shost(tgt));
        SNIC_SCSI_DBG(snic->shost, "tgt_abt_io: Cleaning Pending IOs.\n");

        if (tgt->tdata.typ == SNIC_TGT_DAS)
                tmf = SNIC_ITMF_ABTS_TASK;
        else
                tmf = SNIC_ITMF_ABTS_TASK_TERM;

        for (tag = 0; tag < snic->max_tag_id; tag++) {
                io_lock = snic_io_lock_tag(snic, tag);

                spin_lock_irqsave(io_lock, flags);
                sc = scsi_host_find_tag(snic->shost, tag);
                if (!sc) {
                        spin_unlock_irqrestore(io_lock, flags);

                        continue;
                }

                sc_tgt = starget_to_tgt(scsi_target(sc->device));
                if (sc_tgt != tgt) {
                        spin_unlock_irqrestore(io_lock, flags);

                        continue;
                }
                spin_unlock_irqrestore(io_lock, flags);

                ret = snic_internal_abort_io(snic, sc, tmf);
                if (ret < 0) {
                        SNIC_HOST_ERR(snic->shost,
                                      "tgt_abt_io: Tag %x, Failed w err = %d\n",
                                      tag, ret);

                        continue;
                }

                if (ret == SUCCESS)
                        abt_cnt++;
        }

        SNIC_SCSI_DBG(snic->shost, "tgt_abt_io: abt_cnt = %d\n", abt_cnt);

        return 0;
} /* end of snic_tgt_scsi_abort_io */