diff mbox

[v2,5/9] snic:add SCSI handling, AEN, and fwreset handling

Message ID 1426093299-4511-6-git-send-email-nmusini@cisco.com (mailing list archive)
State New, archived
Headers show

Commit Message

Narsimhulu Musini March 11, 2015, 5:01 p.m. UTC
snic_scsi.c contains scsi handling, includes queuing io, abort, lun reset,
and host reset. Also it handles asynchronous event notifications from FW.

v2
Changed queuecommand to lock-free version.
Converted custom error codes to standard error codes.

Signed-off-by: Narsimhulu Musini <nmusini@cisco.com>
Signed-off-by: Sesidhar Baddela <sebaddel@cisco.com>
---
 drivers/scsi/snic/snic_scsi.c | 2631 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 2631 insertions(+)
 create mode 100644 drivers/scsi/snic/snic_scsi.c

Comments

Hannes Reinecke March 25, 2015, 11:01 a.m. UTC | #1
Hi Narsimhulu,

On 03/11/2015 06:01 PM, Narsimhulu Musini wrote:
> snic_scsi.c contains scsi handling, includes queuing io, abort, lun reset,
> and host reset. Also it handles asynchronous event notifications from FW.
> 
> v2
> Changed queuecommand to lock-free version.
> Converted custom error codes to standard error codes.
> 
> Signed-off-by: Narsimhulu Musini <nmusini@cisco.com>
> Signed-off-by: Sesidhar Baddela <sebaddel@cisco.com>
> ---
>  drivers/scsi/snic/snic_scsi.c | 2631 +++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 2631 insertions(+)
>  create mode 100644 drivers/scsi/snic/snic_scsi.c
> 
> diff --git a/drivers/scsi/snic/snic_scsi.c b/drivers/scsi/snic/snic_scsi.c
> new file mode 100644
> index 0000000..f82ff02
> --- /dev/null
> +++ b/drivers/scsi/snic/snic_scsi.c
> @@ -0,0 +1,2631 @@
> +/*
> + * Copyright 2014 Cisco Systems, Inc.  All rights reserved.
> + *
> + * This program is free software; you may redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; version 2 of the License.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
> + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
> + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
> + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
> + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
> + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
> + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
> + * SOFTWARE.
> + */
> +
> +#include <linux/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"
> +#include "snic_os.h"
> +
> +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_COMPELTE",
> +	[SNIC_IOREQ_LR_PENDING]	= "SNIC_IOREQ_LR_PENDING",
> +	[SNIC_IOREQ_LR_COMPLETE] = "SNIC_IOREQ_LR_COMPELTE",
> +	[SNIC_IOREQ_COMPLETE]	= "SNIC_IOREQ_CMD_COMPELTE",
> +};
> +
> +/* 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%x\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)
> +		pci_unmap_single(snic->pdev,
> +				 req->u.icmnd.sense_addr,
> +				 SCSI_SENSE_BUFFERSIZE,
> +				 PCI_DMA_FROMDEVICE);
> +
> +	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;
> +	int 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 = pci_map_single(snic->pdev,
> +			    sc->sense_buffer,
> +			    SCSI_SENSE_BUFFERSIZE,
> +			    PCI_DMA_FROMDEVICE);
> +
> +	if (pci_dma_mapping_error(snic->pdev, 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 */
> +			(u64)rqi,
> +			flags, /* command flags */
> +			rqi->tgt_id,
> +			lun.scsi_lun,
> +			sc->cmnd,
> +			sc->cmd_len,
> +			scsi_bufflen(sc),
> +			sg_cnt,
> +			(u64)req_to_sgl(rqi->req),
> +			pa, /* sense buffer pa */
> +			SCSI_SENSE_BUFFERSIZE);
> +
> +	ret = snic_queue_wq_desc(snic, rqi->req, rqi->req_len);
> +	if (ret)
> +		SNIC_HOST_ERR(snic->shost,
> +			      "QIcmnd: Queuing Icmnd Failed. ret = %d\n",
> +			      ret);
> +
> +	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, (u64)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, (u64)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, (u64)sc, (u64)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
> + */
> +int
> +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;
> +		sc->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);
> +
> +#ifdef SNIC_DEBUG
> +	scsi_print_command(sc);
> +#endif
> +
> +	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;
> +	} else
> +		snic_stats_update_active_ios(&snic->s_stats);
> +
> +	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_ERROR;
> +		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, 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);
> +		res = DID_ERROR;
> +		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_DEV_OFFLINE:	/* Device offline */
> +	case SNIC_STAT_NOT_READY:	/* XPT yet to initialize */
> +	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%x\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;
> +	u64 xfer_len = 0;
> +	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;
> +
> +		xfer_len = scsi_bufflen(sc);
> +
> +		/* Update SCSI Cmd with resid value */
> +		scsi_set_resid(sc, icmnd_cmpl->resid);
> +
> +		if (icmnd_cmpl->flags & SNIC_ICMND_CMPL_UNDR_RUN) {
> +			xfer_len -= icmnd_cmpl->resid;
> +			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%x\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;
> +	u64 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 = %llx\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),
> +			 fwreq, icmnd_cmpl->resid, ctx);
> +
> +		return;
> +	}
> +
> +
> +#ifdef SNIC_DEBUG
> +	scsi_print_result(sc);
> +#endif
> +
> +	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 %xrqi %p\n",
> +		      sc->device->lun, sc, sc->cmnd[0], snic_cmd_tag(sc),
> +		      CMD_FLAGS(sc), rqi);
> +
> +	SNIC_BUG_ON(rqi != (struct snic_req_info *)ctx);
> +	WARN_ON_ONCE(req);

Now that is curious.
'ctx' already points to the 'snic_req_info', so why do we need to
have this double lookup here?
'scsi_host_find_tag' above already will tell us if the command is
valid; the tag map is managed by the driver, after all, so the
driver will guarantee that a busy tag will not be reused.

Why can't we do away with the 'CMD_SP' reference and get the
scsi command via tag lookup?
That would simplify the code by quite a bit ...

> +	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%x\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%x\n",
> +			      snic_ioreq_state_to_str(CMD_STATE(sc)),
> +			      snic_io_status_to_str(hdr_stat),
> +			      sc, sc_stat, icmnd_cmpl->resid, CMD_FLAGS(sc));
> +
> +		SNIC_TRC(snic->shost->host_no, cmnd_id, sc,
> +			 jiffies_to_msecs(jiffies - start_time), fwreq,
> +			 SNIC_TRC_CMD(sc), SNIC_TRC_CMD_STATE_FLAGS(sc));
> +
> +		return;
> +	}
> +
> +	if (snic_process_icmnd_cmpl_status(snic, icmnd_cmpl, hdr_stat, sc)) {
> +#ifdef SNIC_DEBUG
> +		scsi_print_command(sc);
> +#endif
> +		SNIC_HOST_ERR(snic->shost,
> +			      "icmnd_cmpl:IO Failed, sc 0x%p Tag %d Cmd %x Hdr Status %s flags 0x%x\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;
> +

And then we wouldn't have to modify the CMD_SP() here ...

> +	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, (u64)sc,
> +		 jiffies_to_msecs(jiffies - start_time), (u64)fwreq,
> +		 SNIC_TRC_CMD(sc), SNIC_TRC_CMD_STATE_FLAGS(sc));
> +
> +
> +	if (sc->scsi_done)
> +		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, sc,
> +			 jiffies_to_msecs(jiffies - start_time),
> +			 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%x\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, sc,
> +			 jiffies_to_msecs(jiffies - start_time),
> +			 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%x\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%x\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);
> +	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%x\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%x\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%x\n",
> +			      sc, CMD_FLAGS(sc));
> +
> +		spin_unlock_irqrestore(io_lock, flags);
> +
> +		snic_release_req_buf(snic, rqi, sc);
> +
> +		if (sc->scsi_done) {
> +			SNIC_TRC(snic->shost->host_no, cmnd_id, sc,
> +				 jiffies_to_msecs(jiffies - start_time),
> +				 fwreq,
> +				 SNIC_TRC_CMD(sc),
> +				 SNIC_TRC_CMD_STATE_FLAGS(sc));
> +
> +			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%x\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%x\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;
> +	u64 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 = %llx\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",
> +		      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);
> +
Same issue here.
Why can't you rely on the tag to get the command?
Then you wouldn't have to to the triple indirection

rqi->sc->rpi

_and_ you would be insulated against command timeouts, where
'sc' might become invalid ...

> +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)
> +{
> +	u64 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_HOST_INFO(snic->shost,
> +		       "reset_cmpl:HBA Reset Completion received.\n");
> +
> +	snic_io_hdr_dec(&fwreq->hdr, &typ, &hdr_stat, &cmnd_id, &hid, &ctx);
> +	SNIC_SCSI_DBG(snic->shost,
> +		      "reset_cmpl: type = %x, hdr_stat = %x, cmnd_id = %x, hid = %x, ctx = %llx\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;
> +		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;
> +	}
> +
> +	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 timout\n");
> +		ret = 1;
> +
> +		return ret;
> +	}
> +
> +	rqi = (struct snic_req_info *) CMD_SP(sc);
> +	WARN_ON_ONCE(!rqi);
> +
See above.

If possible I would avoid keeping direct references to the scsi
command in the firmware request structure; the scsi command might
timeout while the firmware request is in flight, leaving the
firmware request with a stale pointer.
I would rather use the tag in the firmware request and use
the tag lookup to get to the command.

Cheers,

Hannes
Narsimhulu Musini April 2, 2015, 8:06 a.m. UTC | #2
Hi Hannes,

  Thank you for reviewing the patch. Please find responses inline.
I will incorporate the comments and suggestions in next patch submittal.



On 25/03/15 4:31 pm, "Hannes Reinecke" <hare@suse.de> wrote:

>Hi Narsimhulu,
>
>On 03/11/2015 06:01 PM, Narsimhulu Musini wrote:
>> snic_scsi.c contains scsi handling, includes queuing io, abort, lun
>>reset,
>> and host reset. Also it handles asynchronous event notifications from
>>FW.
>> 
>> v2
>> Changed queuecommand to lock-free version.
>> Converted custom error codes to standard error codes.
>> 
>> Signed-off-by: Narsimhulu Musini <nmusini@cisco.com>
>> Signed-off-by: Sesidhar Baddela <sebaddel@cisco.com>
>> ---
>>  drivers/scsi/snic/snic_scsi.c | 2631
>>+++++++++++++++++++++++++++++++++++++++++
>>  1 file changed, 2631 insertions(+)
>>  create mode 100644 drivers/scsi/snic/snic_scsi.c
>> 
>> diff --git a/drivers/scsi/snic/snic_scsi.c
>>b/drivers/scsi/snic/snic_scsi.c
>> new file mode 100644
>> index 0000000..f82ff02
>> --- /dev/null
>> +++ b/drivers/scsi/snic/snic_scsi.c
>> @@ -0,0 +1,2631 @@
>> +/*
>> + * Copyright 2014 Cisco Systems, Inc.  All rights reserved.
>> + *
>> + * This program is free software; you may redistribute it and/or modify
>> + * it under the terms of the GNU General Public License as published by
>> + * the Free Software Foundation; version 2 of the License.
>> + *
>> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
>> + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
>> + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
>> + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
>> + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
>> + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
>> + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
>> + * SOFTWARE.
>> + */
>> +
>> +#include <linux/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"
>> +#include "snic_os.h"
>> +
>> +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_COMPELTE",
>> +	[SNIC_IOREQ_LR_PENDING]	= "SNIC_IOREQ_LR_PENDING",
>> +	[SNIC_IOREQ_LR_COMPLETE] = "SNIC_IOREQ_LR_COMPELTE",
>> +	[SNIC_IOREQ_COMPLETE]	= "SNIC_IOREQ_CMD_COMPELTE",
>> +};
>> +
>> +/* 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%x\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)
>> +		pci_unmap_single(snic->pdev,
>> +				 req->u.icmnd.sense_addr,
>> +				 SCSI_SENSE_BUFFERSIZE,
>> +				 PCI_DMA_FROMDEVICE);
>> +
>> +	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;
>> +	int 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 = pci_map_single(snic->pdev,
>> +			    sc->sense_buffer,
>> +			    SCSI_SENSE_BUFFERSIZE,
>> +			    PCI_DMA_FROMDEVICE);
>> +
>> +	if (pci_dma_mapping_error(snic->pdev, 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 */
>> +			(u64)rqi,
>> +			flags, /* command flags */
>> +			rqi->tgt_id,
>> +			lun.scsi_lun,
>> +			sc->cmnd,
>> +			sc->cmd_len,
>> +			scsi_bufflen(sc),
>> +			sg_cnt,
>> +			(u64)req_to_sgl(rqi->req),
>> +			pa, /* sense buffer pa */
>> +			SCSI_SENSE_BUFFERSIZE);
>> +
>> +	ret = snic_queue_wq_desc(snic, rqi->req, rqi->req_len);
>> +	if (ret)
>> +		SNIC_HOST_ERR(snic->shost,
>> +			      "QIcmnd: Queuing Icmnd Failed. ret = %d\n",
>> +			      ret);
>> +
>> +	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, (u64)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, (u64)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, (u64)sc, (u64)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
>> + */
>> +int
>> +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;
>> +		sc->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);
>> +
>> +#ifdef SNIC_DEBUG
>> +	scsi_print_command(sc);
>> +#endif
>> +
>> +	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;
>> +	} else
>> +		snic_stats_update_active_ios(&snic->s_stats);
>> +
>> +	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_ERROR;
>> +		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, 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);
>> +		res = DID_ERROR;
>> +		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_DEV_OFFLINE:	/* Device offline */
>> +	case SNIC_STAT_NOT_READY:	/* XPT yet to initialize */
>> +	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%x\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;
>> +	u64 xfer_len = 0;
>> +	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;
>> +
>> +		xfer_len = scsi_bufflen(sc);
>> +
>> +		/* Update SCSI Cmd with resid value */
>> +		scsi_set_resid(sc, icmnd_cmpl->resid);
>> +
>> +		if (icmnd_cmpl->flags & SNIC_ICMND_CMPL_UNDR_RUN) {
>> +			xfer_len -= icmnd_cmpl->resid;
>> +			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%x\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;
>> +	u64 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 = %llx\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),
>> +			 fwreq, icmnd_cmpl->resid, ctx);
>> +
>> +		return;
>> +	}
>> +
>> +
>> +#ifdef SNIC_DEBUG
>> +	scsi_print_result(sc);
>> +#endif
>> +
>> +	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 %xrqi %p\n",
>> +		      sc->device->lun, sc, sc->cmnd[0], snic_cmd_tag(sc),
>> +		      CMD_FLAGS(sc), rqi);
>> +
>> +	SNIC_BUG_ON(rqi != (struct snic_req_info *)ctx);
>> +	WARN_ON_ONCE(req);
>
>Now that is curious.
>'ctx' already points to the 'snic_req_info', so why do we need to
>have this double lookup here?
>'scsi_host_find_tag' above already will tell us if the command is
>valid; the tag map is managed by the driver, after all, so the
>driver will guarantee that a busy tag will not be reused.
>
>Why can't we do away with the 'CMD_SP' reference and get the
>scsi command via tag lookup?
>That would simplify the code by quite a bit ...

Yes, tag look up is more preferred way. The additional lookup is added to
catch driver and firmware synchronisation issues if there are any.

>
>> +	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%x\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%x\n",
>> +			      snic_ioreq_state_to_str(CMD_STATE(sc)),
>> +			      snic_io_status_to_str(hdr_stat),
>> +			      sc, sc_stat, icmnd_cmpl->resid, CMD_FLAGS(sc));
>> +
>> +		SNIC_TRC(snic->shost->host_no, cmnd_id, sc,
>> +			 jiffies_to_msecs(jiffies - start_time), fwreq,
>> +			 SNIC_TRC_CMD(sc), SNIC_TRC_CMD_STATE_FLAGS(sc));
>> +
>> +		return;
>> +	}
>> +
>> +	if (snic_process_icmnd_cmpl_status(snic, icmnd_cmpl, hdr_stat, sc)) {
>> +#ifdef SNIC_DEBUG
>> +		scsi_print_command(sc);
>> +#endif
>> +		SNIC_HOST_ERR(snic->shost,
>> +			      "icmnd_cmpl:IO Failed, sc 0x%p Tag %d Cmd %x Hdr Status %s
>>flags 0x%x\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;
>> +
>
>And then we wouldn't have to modify the CMD_SP() here ...
>
>> +	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, (u64)sc,
>> +		 jiffies_to_msecs(jiffies - start_time), (u64)fwreq,
>> +		 SNIC_TRC_CMD(sc), SNIC_TRC_CMD_STATE_FLAGS(sc));
>> +
>> +
>> +	if (sc->scsi_done)
>> +		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, sc,
>> +			 jiffies_to_msecs(jiffies - start_time),
>> +			 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%x\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, sc,
>> +			 jiffies_to_msecs(jiffies - start_time),
>> +			 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%x\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%x\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);
>> +	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%x\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%x\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%x\n",
>> +			      sc, CMD_FLAGS(sc));
>> +
>> +		spin_unlock_irqrestore(io_lock, flags);
>> +
>> +		snic_release_req_buf(snic, rqi, sc);
>> +
>> +		if (sc->scsi_done) {
>> +			SNIC_TRC(snic->shost->host_no, cmnd_id, sc,
>> +				 jiffies_to_msecs(jiffies - start_time),
>> +				 fwreq,
>> +				 SNIC_TRC_CMD(sc),
>> +				 SNIC_TRC_CMD_STATE_FLAGS(sc));
>> +
>> +			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%x\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%x\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;
>> +	u64 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 = %llx\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",
>> +		      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);
>> +
>Same issue here.
>Why can't you rely on the tag to get the command?
>Then you wouldn't have to to the triple indirection
>
>rqi->sc->rpi
>
>_and_ you would be insulated against command timeouts, where
>'sc' might become invalid ...
Yes, all the time driver relies on tag to get scsi command. But there are
few instances, where scsi command is not associated with a tag. For
example lun reset or host reset are issued through ioctl. In the
exceptional case, where scsi command is not associated with a valid tag,
then driver uses this triple redirection. It is common code to handle
tagged and untagged commands.

>
>> +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)
>> +{
>> +	u64 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_HOST_INFO(snic->shost,
>> +		       "reset_cmpl:HBA Reset Completion received.\n");
>> +
>> +	snic_io_hdr_dec(&fwreq->hdr, &typ, &hdr_stat, &cmnd_id, &hid, &ctx);
>> +	SNIC_SCSI_DBG(snic->shost,
>> +		      "reset_cmpl: type = %x, hdr_stat = %x, cmnd_id = %x, hid = %x, 
>>ctx = %llx\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;
>> +		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;
>> +	}
>> +
>> +	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 timout\n");
>> +		ret = 1;
>> +
>> +		return ret;
>> +	}
>> +
>> +	rqi = (struct snic_req_info *) CMD_SP(sc);
>> +	WARN_ON_ONCE(!rqi);
>> +
>See above.
>
>If possible I would avoid keeping direct references to the scsi
>command in the firmware request structure; the scsi command might
>timeout while the firmware request is in flight, leaving the
>firmware request with a stale pointer.
>I would rather use the tag in the firmware request and use
>the tag lookup to get to the command.
 You are correct. But there are few instances, where scsi command is not 
associated with a tag. For example lun reset or host reset are issued 
through ioctl. In the exceptional case, where scsi command is not 
associated with a valid tag, driver accesses the scsi command directly.

>
>Cheers,
>
>Hannes
>-- 
>Dr. Hannes Reinecke		               zSeries & Storage
>hare@suse.de			               +49 911 74053 688
>SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg
>GF: F. Imendörffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton
>HRB 21284 (AG Nürnberg)
Thanks
Narsimhulu
>

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diff mbox

Patch

diff --git a/drivers/scsi/snic/snic_scsi.c b/drivers/scsi/snic/snic_scsi.c
new file mode 100644
index 0000000..f82ff02
--- /dev/null
+++ b/drivers/scsi/snic/snic_scsi.c
@@ -0,0 +1,2631 @@ 
+/*
+ * Copyright 2014 Cisco Systems, Inc.  All rights reserved.
+ *
+ * This program is free software; you may redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <linux/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"
+#include "snic_os.h"
+
+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_COMPELTE",
+	[SNIC_IOREQ_LR_PENDING]	= "SNIC_IOREQ_LR_PENDING",
+	[SNIC_IOREQ_LR_COMPLETE] = "SNIC_IOREQ_LR_COMPELTE",
+	[SNIC_IOREQ_COMPLETE]	= "SNIC_IOREQ_CMD_COMPELTE",
+};
+
+/* 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%x\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)
+		pci_unmap_single(snic->pdev,
+				 req->u.icmnd.sense_addr,
+				 SCSI_SENSE_BUFFERSIZE,
+				 PCI_DMA_FROMDEVICE);
+
+	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;
+	int 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 = pci_map_single(snic->pdev,
+			    sc->sense_buffer,
+			    SCSI_SENSE_BUFFERSIZE,
+			    PCI_DMA_FROMDEVICE);
+
+	if (pci_dma_mapping_error(snic->pdev, 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 */
+			(u64)rqi,
+			flags, /* command flags */
+			rqi->tgt_id,
+			lun.scsi_lun,
+			sc->cmnd,
+			sc->cmd_len,
+			scsi_bufflen(sc),
+			sg_cnt,
+			(u64)req_to_sgl(rqi->req),
+			pa, /* sense buffer pa */
+			SCSI_SENSE_BUFFERSIZE);
+
+	ret = snic_queue_wq_desc(snic, rqi->req, rqi->req_len);
+	if (ret)
+		SNIC_HOST_ERR(snic->shost,
+			      "QIcmnd: Queuing Icmnd Failed. ret = %d\n",
+			      ret);
+
+	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, (u64)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, (u64)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, (u64)sc, (u64)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
+ */
+int
+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;
+		sc->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);
+
+#ifdef SNIC_DEBUG
+	scsi_print_command(sc);
+#endif
+
+	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;
+	} else
+		snic_stats_update_active_ios(&snic->s_stats);
+
+	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_ERROR;
+		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, 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);
+		res = DID_ERROR;
+		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_DEV_OFFLINE:	/* Device offline */
+	case SNIC_STAT_NOT_READY:	/* XPT yet to initialize */
+	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%x\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;
+	u64 xfer_len = 0;
+	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;
+
+		xfer_len = scsi_bufflen(sc);
+
+		/* Update SCSI Cmd with resid value */
+		scsi_set_resid(sc, icmnd_cmpl->resid);
+
+		if (icmnd_cmpl->flags & SNIC_ICMND_CMPL_UNDR_RUN) {
+			xfer_len -= icmnd_cmpl->resid;
+			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%x\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;
+	u64 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 = %llx\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),
+			 fwreq, icmnd_cmpl->resid, ctx);
+
+		return;
+	}
+
+
+#ifdef SNIC_DEBUG
+	scsi_print_result(sc);
+#endif
+
+	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 %xrqi %p\n",
+		      sc->device->lun, sc, sc->cmnd[0], snic_cmd_tag(sc),
+		      CMD_FLAGS(sc), rqi);
+
+	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%x\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%x\n",
+			      snic_ioreq_state_to_str(CMD_STATE(sc)),
+			      snic_io_status_to_str(hdr_stat),
+			      sc, sc_stat, icmnd_cmpl->resid, CMD_FLAGS(sc));
+
+		SNIC_TRC(snic->shost->host_no, cmnd_id, sc,
+			 jiffies_to_msecs(jiffies - start_time), fwreq,
+			 SNIC_TRC_CMD(sc), SNIC_TRC_CMD_STATE_FLAGS(sc));
+
+		return;
+	}
+
+	if (snic_process_icmnd_cmpl_status(snic, icmnd_cmpl, hdr_stat, sc)) {
+#ifdef SNIC_DEBUG
+		scsi_print_command(sc);
+#endif
+		SNIC_HOST_ERR(snic->shost,
+			      "icmnd_cmpl:IO Failed, sc 0x%p Tag %d Cmd %x Hdr Status %s flags 0x%x\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, (u64)sc,
+		 jiffies_to_msecs(jiffies - start_time), (u64)fwreq,
+		 SNIC_TRC_CMD(sc), SNIC_TRC_CMD_STATE_FLAGS(sc));
+
+
+	if (sc->scsi_done)
+		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, sc,
+			 jiffies_to_msecs(jiffies - start_time),
+			 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%x\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, sc,
+			 jiffies_to_msecs(jiffies - start_time),
+			 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%x\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%x\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);
+	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%x\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%x\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%x\n",
+			      sc, CMD_FLAGS(sc));
+
+		spin_unlock_irqrestore(io_lock, flags);
+
+		snic_release_req_buf(snic, rqi, sc);
+
+		if (sc->scsi_done) {
+			SNIC_TRC(snic->shost->host_no, cmnd_id, sc,
+				 jiffies_to_msecs(jiffies - start_time),
+				 fwreq,
+				 SNIC_TRC_CMD(sc),
+				 SNIC_TRC_CMD_STATE_FLAGS(sc));
+
+			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%x\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%x\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;
+	u64 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 = %llx\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",
+		      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)
+{
+	u64 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_HOST_INFO(snic->shost,
+		       "reset_cmpl:HBA Reset Completion received.\n");
+
+	snic_io_hdr_dec(&fwreq->hdr, &typ, &hdr_stat, &cmnd_id, &hid, &ctx);
+	SNIC_SCSI_DBG(snic->shost,
+		      "reset_cmpl: type = %x, hdr_stat = %x, cmnd_id = %x, hid = %x, ctx = %llx\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;
+		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;
+	}
+
+	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 timout\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 %x\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;
+	u64 ctx;
+	struct snic_async_evnotify *aen = &fwreq->u.async_ev;
+
+	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 = %llx\n",
+		      typ, hdr_stat, cmnd_id, hid, ctx);
+
+	switch (aen->ev_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 = vnic_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 Firmwqre 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,
+		       (u64) 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);
+	if (ret)
+		goto tmreq_err;
+
+	ret = 0;
+
+tmreq_err:
+	if (ret) {
+		SNIC_HOST_ERR(snic->shost,
+			      "issu_tmreq: Queing 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: Queuing 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%x\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 %x\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;
+		break;
+
+	default:
+		/* Firmware completed abort with error */
+		ret = FAILED;
+		break;
+	}
+
+	CMD_SP(sc) = NULL;
+	SNIC_HOST_INFO(snic->shost,
+		       "abt_fini: Tag %x, Cmpl Status %s flags 0x%x\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%x\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) {
+		SNIC_HOST_ERR(snic->shost,
+			      "send_abt_cmd: IO w/ Tag 0x%x fail w/ err %d flags 0x%x\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 %x\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], sc->request, 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, 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%x\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 %dflags %x\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);
+
+	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 = FAILED;
+
+	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)) {
+		ret = FAILED;
+
+		goto clean_err;
+	}
+
+	ret = 0;
+	SNIC_SCSI_DBG(snic->shost, "clean_pending_req: Success.\n");
+
+	return ret;
+
+clean_err:
+	ret = FAILED;
+	SNIC_HOST_ERR(snic->shost,
+		      "Failed to Clean Pending IOs on %s device.\n",
+		      dev_name(&lr_sdev->sdev_gendev));
+
+	return ret;
+
+} /* 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%x\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 %x\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%x\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:
+	SNIC_BUG_ON(!spin_is_locked(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%x\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%x\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), sc,
+		 jiffies_to_msecs(jiffies - start_time),
+		 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], sc->request,
+		      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;
+
+		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, 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) {
+		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, (u64)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 progres\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 = FAILED;
+
+	SNIC_SCSI_DBG(shost,
+		      "host reset:sc %p sc_cmd 0x%x req %p tag %d flags 0x%x\n",
+		      sc, sc->cmnd[0], sc->request,
+		      snic_cmd_tag(sc), CMD_FLAGS(sc));
+
+	ret = snic_reset(shost, sc);
+
+	SNIC_TRC(shost->host_no, snic_cmd_tag(sc), 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%x\n",
+		      sc, snic_io_status_to_str(CMD_STATE(sc)), CMD_FLAGS(sc));
+
+	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 %x\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%x\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. rqi %p duration %llu msecs\n",
+			       sc, rqi, (jiffies - st_time));
+
+		/* Update IO stats */
+		snic_stats_update_io_cmpl(&snic->s_stats);
+
+		if (sc->scsi_done) {
+			SNIC_TRC(snic->shost->host_no, tag, sc,
+				 jiffies_to_msecs(jiffies - st_time), 0,
+				 SNIC_TRC_CMD(sc),
+				 SNIC_TRC_CMD_STATE_FLAGS(sc));
+
+			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 %x 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:
+	SNIC_BUG_ON(!spin_is_locked(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 */