[04/24] mpi3mr: add support of queue command processing

Commit Message

Kashyap Desai Dec. 22, 2020, 10:11 a.m. UTC

Send Port Enable Request to FW for Device Discovery.
As part of port enable completion driver calls scan_start and
scan_finished hooks.
scsi layer reference like sdev, starget etc is added but actual
device discovery will be supported once driver add complete event
process handling (It is added in subsequent patches)

This patch provides interface which is used to interact with FW
via operational queue pairs.

Signed-off-by: Kashyap Desai <[e-mail]>
Cc: [e-mail]
---
 drivers/scsi/mpi3mr/mpi3mr.h    |  52 +++
 drivers/scsi/mpi3mr/mpi3mr_fw.c | 251 +++++++++++++
 drivers/scsi/mpi3mr/mpi3mr_os.c | 645 +++++++++++++++++++++++++++++++-
 3 files changed, 946 insertions(+), 2 deletions(-)

Comments

Tomas Henzl Feb. 22, 2021, 3:23 p.m. UTC | #1

On 12/22/20 11:11 AM, Kashyap Desai wrote:
> Send Port Enable Request to FW for Device Discovery.
> As part of port enable completion driver calls scan_start and
> scan_finished hooks.
> scsi layer reference like sdev, starget etc is added but actual
> device discovery will be supported once driver add complete event
> process handling (It is added in subsequent patches)
> 
> This patch provides interface which is used to interact with FW
> via operational queue pairs.
> 
> Signed-off-by: Kashyap Desai <[e-mail]>
> Cc: [e-mail]
> ---
>  drivers/scsi/mpi3mr/mpi3mr.h    |  52 +++
>  drivers/scsi/mpi3mr/mpi3mr_fw.c | 251 +++++++++++++
>  drivers/scsi/mpi3mr/mpi3mr_os.c | 645 +++++++++++++++++++++++++++++++-
>  3 files changed, 946 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/scsi/mpi3mr/mpi3mr.h b/drivers/scsi/mpi3mr/mpi3mr.h
> index fe6094bb357a..f23751e25d0f 100644
> --- a/drivers/scsi/mpi3mr/mpi3mr.h
> +++ b/drivers/scsi/mpi3mr/mpi3mr.h
> @@ -96,6 +96,7 @@ extern struct list_head mrioc_list;
>  
>  /* command/controller interaction timeout definitions in seconds */
>  #define MPI3MR_INTADMCMD_TIMEOUT		10
> +#define MPI3MR_PORTENABLE_TIMEOUT		300
>  #define MPI3MR_RESETTM_TIMEOUT			30
>  #define MPI3MR_DEFAULT_SHUTDOWN_TIME		120
>  
> @@ -312,6 +313,43 @@ struct mpi3mr_intr_info {
>  	char name[MPI3MR_NAME_LENGTH];
>  };
>  
> +/**
> + * struct mpi3mr_stgt_priv_data - SCSI target private structure
> + *
> + * @starget: Scsi_target pointer
> + * @dev_handle: FW device handle
> + * @perst_id: FW assigned Persistent ID
> + * @num_luns: Number of Logical Units
> + * @block_io: I/O blocked to the device or not
> + * @dev_removed: Device removed in the Firmware
> + * @dev_removedelay: Device is waiting to be removed in FW
> + * @dev_type: Device type
> + * @tgt_dev: Internal target device pointer
> + */
> +struct mpi3mr_stgt_priv_data {
> +	struct scsi_target *starget;
> +	u16 dev_handle;
> +	u16 perst_id;
> +	u32 num_luns;
> +	atomic_t block_io;
> +	u8 dev_removed;
> +	u8 dev_removedelay;
> +	u8 dev_type;
> +	struct mpi3mr_tgt_dev *tgt_dev;
> +};
> +
> +/**
> + * struct mpi3mr_stgt_priv_data - SCSI device private structure
> + *
> + * @tgt_priv_data: Scsi_target private data pointer
> + * @lun_id: LUN ID of the device
> + * @ncq_prio_enable: NCQ priority enable for SATA device
> + */
> +struct mpi3mr_sdev_priv_data {
> +	struct mpi3mr_stgt_priv_data *tgt_priv_data;
> +	u32 lun_id;
> +	u8 ncq_prio_enable;
> +};
>  
>  typedef struct mpi3mr_drv_cmd DRV_CMD;
>  typedef void (*DRV_CMD_CALLBACK)(struct mpi3mr_ioc *mrioc,
> @@ -443,12 +481,16 @@ struct scmd_priv {
>   * @sbq_lock: Sense buffer queue lock
>   * @sbq_host_index: Sense buffer queuehost index
>   * @is_driver_loading: Is driver still loading
> + * @scan_started: Async scan started
> + * @scan_failed: Asycn scan failed
> + * @stop_drv_processing: Stop all command processing
>   * @max_host_ios: Maximum host I/O count
>   * @chain_buf_count: Chain buffer count
>   * @chain_buf_pool: Chain buffer pool
>   * @chain_sgl_list: Chain SGL list
>   * @chain_bitmap_sz: Chain buffer allocator bitmap size
>   * @chain_bitmap: Chain buffer allocator bitmap
> + * @chain_buf_lock: Chain buffer list lock
>   * @reset_in_progress: Reset in progress flag
>   * @unrecoverable: Controller unrecoverable flag
>   * @logging_level: Controller debug logging level
> @@ -533,6 +575,9 @@ struct mpi3mr_ioc {
>  	u32 sbq_host_index;
>  
>  	u8 is_driver_loading;
> +	u8 scan_started;
> +	u16 scan_failed;
> +	u8 stop_drv_processing;
>  
>  	u16 max_host_ios;
>  
> @@ -541,6 +586,7 @@ struct mpi3mr_ioc {
>  	struct chain_element *chain_sgl_list;
>  	u16  chain_bitmap_sz;
>  	void *chain_bitmap;
> +	spinlock_t chain_buf_lock;
>  
>  	u8 reset_in_progress;
>  	u8 unrecoverable;
> @@ -557,8 +603,11 @@ int mpi3mr_setup_resources(struct mpi3mr_ioc *mrioc);
>  void mpi3mr_cleanup_resources(struct mpi3mr_ioc *mrioc);
>  int mpi3mr_init_ioc(struct mpi3mr_ioc *mrioc);
>  void mpi3mr_cleanup_ioc(struct mpi3mr_ioc *mrioc);
> +int mpi3mr_issue_port_enable(struct mpi3mr_ioc *mrioc, u8 async);
>  int mpi3mr_admin_request_post(struct mpi3mr_ioc *mrioc, void *admin_req,
>  u16 admin_req_sz, u8 ignore_reset);
> +int mpi3mr_op_request_post(struct mpi3mr_ioc *mrioc,
> +			   struct op_req_qinfo *opreqq, u8 *req);
>  void mpi3mr_add_sg_single(void *paddr, u8 flags, u32 length,
>  			  dma_addr_t dma_addr);
>  void mpi3mr_build_zero_len_sge(void *paddr);
> @@ -569,6 +618,9 @@ void *mpi3mr_get_reply_virt_addr(struct mpi3mr_ioc *mrioc,
>  void mpi3mr_repost_sense_buf(struct mpi3mr_ioc *mrioc,
>  				     u64 sense_buf_dma);
>  
> +void mpi3mr_process_op_reply_desc(struct mpi3mr_ioc *mrioc,
> +				  Mpi3DefaultReplyDescriptor_t *reply_desc,
> +				  u64 *reply_dma, u16 qidx);
>  void mpi3mr_start_watchdog(struct mpi3mr_ioc *mrioc);
>  void mpi3mr_stop_watchdog(struct mpi3mr_ioc *mrioc);
>  
> diff --git a/drivers/scsi/mpi3mr/mpi3mr_fw.c b/drivers/scsi/mpi3mr/mpi3mr_fw.c
> index 6fb28983038e..abdf8c653e6b 100644
> --- a/drivers/scsi/mpi3mr/mpi3mr_fw.c
> +++ b/drivers/scsi/mpi3mr/mpi3mr_fw.c
> @@ -24,6 +24,23 @@ static inline void mpi3mr_writeq(__u64 b, volatile void __iomem *addr)
>  }
>  #endif
>  
> +static inline bool
> +mpi3mr_check_req_qfull(struct op_req_qinfo *op_req_q)
> +{
> +	u16 pi, ci, max_entries;
> +	bool is_qfull = false;
> +
> +	pi = op_req_q->pi;
> +	ci = op_req_q->ci;
> +	max_entries = op_req_q->num_requests;
> +
> +	if ((ci == (pi + 1)) || ((!ci) && (pi == (max_entries - 1))))
> +		is_qfull = true;
> +
> +	return is_qfull;
> +}
> +
> +
>  static void mpi3mr_sync_irqs(struct mpi3mr_ioc *mrioc)
>  {
>  	u16 i, max_vectors;
> @@ -282,6 +299,87 @@ static int mpi3mr_process_admin_reply_q(struct mpi3mr_ioc *mrioc)
>  	return num_admin_replies;
>  }
>  
> +/**
> + * mpi3mr_get_reply_desc - get reply descriptor frame corresponding to
> + *	queue's consumer index from operational reply descriptor queue.
> + * @op_reply_q: op_reply_qinfo object
> + * @reply_ci: operational reply descriptor's queue consumer index
> + *
> + * Returns reply descriptor frame address
> + */
> +static inline Mpi3DefaultReplyDescriptor_t *
> +mpi3mr_get_reply_desc(struct op_reply_qinfo *op_reply_q, u32 reply_ci)
> +{
> +	void *segment_base_addr;
> +	struct segments *segments = op_reply_q->q_segments;
> +	Mpi3DefaultReplyDescriptor_t *reply_desc = NULL;
> +
> +	segment_base_addr =
> +	    segments[reply_ci / op_reply_q->segment_qd].segment;
> +	reply_desc = (Mpi3DefaultReplyDescriptor_t *)segment_base_addr +
> +	    (reply_ci % op_reply_q->segment_qd);
> +	return reply_desc;
> +}
> +
> +
> +static int mpi3mr_process_op_reply_q(struct mpi3mr_ioc *mrioc,
> +	struct mpi3mr_intr_info *intr_info)
> +{
> +	struct op_reply_qinfo *op_reply_q = intr_info->op_reply_q;
> +	struct op_req_qinfo *op_req_q;
> +	u32 exp_phase;
> +	u32 reply_ci;
> +	u32 num_op_reply = 0;
> +	u64 reply_dma = 0;
> +	Mpi3DefaultReplyDescriptor_t *reply_desc;
> +	u16 req_q_idx = 0, reply_qidx;
> +
> +	reply_qidx = op_reply_q->qid - 1;
> +
> +	exp_phase = op_reply_q->ephase;
> +	reply_ci = op_reply_q->ci;
> +
> +	reply_desc = mpi3mr_get_reply_desc(op_reply_q, reply_ci);
> +	if ((le16_to_cpu(reply_desc->ReplyFlags) &
> +	    MPI3_REPLY_DESCRIPT_FLAGS_PHASE_MASK) != exp_phase) {
> +		return 0;
> +	}
> +
> +	do {
> +		req_q_idx = le16_to_cpu(reply_desc->RequestQueueID) - 1;
> +		op_req_q = &mrioc->req_qinfo[req_q_idx];
> +
> +		op_req_q->ci =
> +		    le16_to_cpu(reply_desc->RequestQueueCI);
> +
> +		mpi3mr_process_op_reply_desc(mrioc, reply_desc, &reply_dma,
> +		    reply_qidx);
> +		if (reply_dma)
> +			mpi3mr_repost_reply_buf(mrioc, reply_dma);
> +		num_op_reply++;
> +
> +		if (++reply_ci == op_reply_q->num_replies) {
> +			reply_ci = 0;
> +			exp_phase ^= 1;
> +		}
> +
> +		reply_desc = mpi3mr_get_reply_desc(op_reply_q, reply_ci);
> +
> +		if ((le16_to_cpu(reply_desc->ReplyFlags) &
> +		    MPI3_REPLY_DESCRIPT_FLAGS_PHASE_MASK) != exp_phase)
> +			break;
> +
> +	} while (1);
> +
> +
> +	writel(reply_ci,
> +	    &mrioc->sysif_regs->OperQueueIndexes[reply_qidx].ConsumerIndex);
> +	op_reply_q->ci = reply_ci;
> +	op_reply_q->ephase = exp_phase;
> +
> +	return num_op_reply;
> +}
> +
>  static irqreturn_t mpi3mr_isr_primary(int irq, void *privdata)
>  {
>  	struct mpi3mr_intr_info *intr_info = privdata;
> @@ -1314,6 +1412,74 @@ static int mpi3mr_create_op_queues(struct mpi3mr_ioc *mrioc)
>  	return retval;
>  }
>  
> +/**
> + * mpi3mr_op_request_post - Post request to operational queue
> + * @mrioc: Adapter reference
> + * @op_req_q: Operational request queue info
> + * @req: MPI3 request
> + *
> + * Post the MPI3 request into operational request queue and
> + * inform the controller, if the queue is full return
> + * appropriate error.
> + *
> + * Return: 0 on success, non-zero on failure.
> + */
> +int mpi3mr_op_request_post(struct mpi3mr_ioc *mrioc,
> +	struct op_req_qinfo *op_req_q, u8 *req)
> +{
> +	u16 pi = 0, max_entries, reply_qidx = 0, midx;
> +	int retval = 0;
> +	unsigned long flags;
> +	u8 *req_entry;
> +	void *segment_base_addr;
> +	u16 req_sz = mrioc->facts.op_req_sz;
> +	struct segments *segments = op_req_q->q_segments;
> +
> +	reply_qidx = op_req_q->reply_qid - 1;
> +
> +	if (mrioc->unrecoverable)
> +		return -EFAULT;
> +
> +	spin_lock_irqsave(&op_req_q->q_lock, flags);
> +	pi = op_req_q->pi;
> +	max_entries = op_req_q->num_requests;
> +
> +	if (mpi3mr_check_req_qfull(op_req_q)) {
> +		midx = REPLY_QUEUE_IDX_TO_MSIX_IDX(
> +		    reply_qidx, mrioc->op_reply_q_offset);
> +		mpi3mr_process_op_reply_q(mrioc, &mrioc->intr_info[midx]);
> +
> +		if (mpi3mr_check_req_qfull(op_req_q)) {
> +			retval = -EAGAIN;
> +			goto out;
> +		}
> +	}
> +
> +	if (mrioc->reset_in_progress) {
> +		ioc_err(mrioc, "OpReqQ submit reset in progress\n");
> +		retval = -EAGAIN;
> +		goto out;
> +	}
> +
> +	segment_base_addr = segments[pi / op_req_q->segment_qd].segment;
> +	req_entry = (u8 *)segment_base_addr +
> +	    ((pi % op_req_q->segment_qd) * req_sz);
> +
> +	memset(req_entry, 0, req_sz);
> +	memcpy(req_entry, req, MPI3MR_ADMIN_REQ_FRAME_SZ);
> +
> +	if (++pi == max_entries)
> +		pi = 0;
> +	op_req_q->pi = pi;
> +
> +	writel(op_req_q->pi,
> +	    &mrioc->sysif_regs->OperQueueIndexes[reply_qidx].ProducerIndex);
> +
> +out:
> +	spin_unlock_irqrestore(&op_req_q->q_lock, flags);
> +	return retval;
> +}
> +
>  
>  /**
>   * mpi3mr_setup_admin_qpair - Setup admin queue pair
> @@ -1901,6 +2067,91 @@ static int mpi3mr_alloc_chain_bufs(struct mpi3mr_ioc *mrioc)
>  	return retval;
>  }
>  
> +/**
> + * mpi3mr_port_enable_complete - Mark port enable complete
> + * @mrioc: Adapter instance reference
> + * @drv_cmd: Internal command tracker
> + *
> + * Call back for asynchronous port enable request sets the
> + * driver command to indicate port enable request is complete.
> + *
> + * Return: Nothing
> + */
> +static void mpi3mr_port_enable_complete(struct mpi3mr_ioc *mrioc,
> +	struct mpi3mr_drv_cmd *drv_cmd)
> +{
> +
> +	drv_cmd->state = MPI3MR_CMD_NOTUSED;
> +	drv_cmd->callback = NULL;
> +	mrioc->scan_failed = drv_cmd->ioc_status;
> +	mrioc->scan_started = 0;
> +
> +}
> +
> +/**
> + * mpi3mr_issue_port_enable - Issue Port Enable
> + * @mrioc: Adapter instance reference
> + * @async: Flag to wait for completion or not
> + *
> + * Issue Port Enable MPI request through admin queue and if the
> + * async flag is not set wait for the completion of the port
> + * enable or time out.
> + *
> + * Return: 0 on success, non-zero on failures.
> + */
> +int mpi3mr_issue_port_enable(struct mpi3mr_ioc *mrioc, u8 async)
> +{
> +	Mpi3PortEnableRequest_t pe_req;
> +	int retval = 0;
> +	u32 pe_timeout = MPI3MR_PORTENABLE_TIMEOUT;
> +
> +	memset(&pe_req, 0, sizeof(pe_req));
> +	mutex_lock(&mrioc->init_cmds.mutex);
> +	if (mrioc->init_cmds.state & MPI3MR_CMD_PENDING) {
> +		retval = -1;
> +		ioc_err(mrioc, "Issue PortEnable: Init command is in use\n");
> +		mutex_unlock(&mrioc->init_cmds.mutex);
> +		goto out;
> +	}
> +	mrioc->init_cmds.state = MPI3MR_CMD_PENDING;
> +	if (async) {
> +		mrioc->init_cmds.is_waiting = 0;
> +		mrioc->init_cmds.callback = mpi3mr_port_enable_complete;
> +	} else {
> +		mrioc->init_cmds.is_waiting = 1;
> +		mrioc->init_cmds.callback = NULL;
> +		init_completion(&mrioc->init_cmds.done);
> +	}
> +	pe_req.HostTag = cpu_to_le16(MPI3MR_HOSTTAG_INITCMDS);
> +	pe_req.Function = MPI3_FUNCTION_PORT_ENABLE;
> +
> +	retval = mpi3mr_admin_request_post(mrioc, &pe_req, sizeof(pe_req), 1);
> +	if (retval) {
> +		ioc_err(mrioc, "Issue PortEnable: Admin Post failed\n");
> +		goto out_unlock;
> +	}
> +	if (!async) {
> +		wait_for_completion_timeout(&mrioc->init_cmds.done,
> +		    (pe_timeout * HZ));
> +		if (!(mrioc->init_cmds.state & MPI3MR_CMD_COMPLETE)) {
> +			ioc_err(mrioc, "Issue PortEnable: command timed out\n");
> +			retval = -1;
> +			mrioc->scan_failed = MPI3_IOCSTATUS_INTERNAL_ERROR;
> +			mpi3mr_set_diagsave(mrioc);
> +			mpi3mr_issue_reset(mrioc,
> +			    MPI3_SYSIF_HOST_DIAG_RESET_ACTION_DIAG_FAULT,
> +			    MPI3MR_RESET_FROM_PE_TIMEOUT);
> +			mrioc->unrecoverable = 1;
> +			goto out_unlock;
> +		}
> +		mpi3mr_port_enable_complete(mrioc, &mrioc->init_cmds);
> +	}
> +out_unlock:
> +	mutex_unlock(&mrioc->init_cmds.mutex);
> +out:
> +	return retval;
> +}
> +
>  
>  /**
>   * mpi3mr_cleanup_resources - Free PCI resources
> diff --git a/drivers/scsi/mpi3mr/mpi3mr_os.c b/drivers/scsi/mpi3mr/mpi3mr_os.c
> index 3cf0be63842f..01be5f337826 100644
> --- a/drivers/scsi/mpi3mr/mpi3mr_os.c
> +++ b/drivers/scsi/mpi3mr/mpi3mr_os.c
> @@ -26,6 +26,471 @@ module_param(logging_level, int, 0);
>  MODULE_PARM_DESC(logging_level,
>  	" bits for enabling additional logging info (default=0)");
>  
> +/* Forward declarations*/
> +/**
> + * mpi3mr_host_tag_for_scmd - Get host tag for a scmd
> + * @mrioc: Adapter instance reference
> + * @scmd: SCSI command reference
> + *
> + * Calculate the host tag based on block tag for a given scmd.
> + *
> + * Return: Valid host tag or MPI3MR_HOSTTAG_INVALID.
> + */
> +static u16 mpi3mr_host_tag_for_scmd(struct mpi3mr_ioc *mrioc,
> +	struct scsi_cmnd *scmd)
> +{
> +	struct scmd_priv *priv = NULL;
> +	u32 unique_tag;
> +	u16 host_tag, hw_queue;
> +
> +	unique_tag = blk_mq_unique_tag(scmd->request);
> +
> +	hw_queue = blk_mq_unique_tag_to_hwq(unique_tag);
> +	if (hw_queue >= mrioc->num_op_reply_q)
> +		return MPI3MR_HOSTTAG_INVALID;
> +	host_tag = blk_mq_unique_tag_to_tag(unique_tag);
> +
> +	if (WARN_ON(host_tag >= mrioc->max_host_ios))
> +		return MPI3MR_HOSTTAG_INVALID;
> +
> +	priv = scsi_cmd_priv(scmd);
> +	/*host_tag 0 is invalid hence incrementing by 1*/
> +	priv->host_tag = host_tag + 1;
> +	priv->scmd = scmd;
> +	priv->in_lld_scope = 1;
> +	priv->req_q_idx = hw_queue;
> +	priv->chain_idx = -1;
> +	return priv->host_tag;
> +}
> +
> +/**
> + * mpi3mr_scmd_from_host_tag - Get SCSI command from host tag
> + * @mrioc: Adapter instance reference
> + * @host_tag: Host tag
> + * @qidx: Operational queue index
> + *
> + * Identify the block tag from the host tag and queue index and
> + * retrieve associated scsi command using scsi_host_find_tag().
> + *
> + * Return: SCSI command reference or NULL.
> + */
> +static struct scsi_cmnd *mpi3mr_scmd_from_host_tag(
> +	struct mpi3mr_ioc *mrioc, u16 host_tag, u16 qidx)
> +{
> +	struct scsi_cmnd *scmd = NULL;
> +	struct scmd_priv *priv = NULL;
> +	u32 unique_tag = host_tag - 1;
> +
> +	if (WARN_ON(host_tag > mrioc->max_host_ios))
> +		goto out;
> +
> +	unique_tag |= (qidx << BLK_MQ_UNIQUE_TAG_BITS);
> +
> +	scmd = scsi_host_find_tag(mrioc->shost, unique_tag);
> +	if (scmd) {
> +		priv = scsi_cmd_priv(scmd);
> +		if (!priv->in_lld_scope)
> +			scmd = NULL;
> +	}
> +out:
> +	return scmd;
> +}
> +
> +/**
> + * mpi3mr_clear_scmd_priv - Cleanup SCSI command private date
> + * @mrioc: Adapter instance reference
> + * @scmd: SCSI command reference
> + *
> + * Invalidate the SCSI command private data to mark the command
> + * is not in LLD scope anymore.
> + *
> + * Return: Nothing.
> + */
> +static void mpi3mr_clear_scmd_priv(struct mpi3mr_ioc *mrioc,
> +	struct scsi_cmnd *scmd)
> +{
> +	struct scmd_priv *priv = NULL;
> +
> +	priv = scsi_cmd_priv(scmd);
> +
> +	if (WARN_ON(priv->in_lld_scope == 0))
> +		return;
> +	priv->host_tag = MPI3MR_HOSTTAG_INVALID;
> +	priv->req_q_idx = 0xFFFF;
> +	priv->scmd = NULL;
> +	priv->in_lld_scope = 0;
> +	if (priv->chain_idx >= 0) {
> +		clear_bit(priv->chain_idx, mrioc->chain_bitmap);
> +		priv->chain_idx = -1;
> +	}
> +}
> +
> +/**
> + * mpi3mr_process_op_reply_desc - reply descriptor handler
> + * @mrioc: Adapter instance reference
> + * @reply_desc: Operational reply descriptor
> + * @reply_dma: place holder for reply DMA address
> + * @qidx: Operational queue index
> + *
> + * Process the operational reply descriptor and identifies the
> + * descriptor type. Based on the descriptor map the MPI3 request
> + * status to a SCSI command status and calls scsi_done call
> + * back.
> + *
> + * Return: Nothing
> + */
> +void mpi3mr_process_op_reply_desc(struct mpi3mr_ioc *mrioc,
> +	Mpi3DefaultReplyDescriptor_t *reply_desc, u64 *reply_dma, u16 qidx)
> +{
> +	u16 reply_desc_type, host_tag = 0;
> +	u16 ioc_status = MPI3_IOCSTATUS_SUCCESS;
> +	u32 ioc_loginfo = 0;
> +	Mpi3StatusReplyDescriptor_t *status_desc = NULL;
> +	Mpi3AddressReplyDescriptor_t *addr_desc = NULL;
> +	Mpi3SuccessReplyDescriptor_t *success_desc = NULL;
> +	Mpi3SCSIIOReply_t *scsi_reply = NULL;
> +	struct scsi_cmnd *scmd = NULL;
> +	struct scmd_priv *priv = NULL;
> +	u8 *sense_buf = NULL;
> +	u8 scsi_state = 0, scsi_status = 0, sense_state = 0;
> +	u32 xfer_count = 0, sense_count = 0, resp_data = 0;
> +	u16 dev_handle = 0xFFFF;
> +	struct scsi_sense_hdr sshdr;
> +
> +	*reply_dma = 0;
> +	reply_desc_type = le16_to_cpu(reply_desc->ReplyFlags) &
> +	    MPI3_REPLY_DESCRIPT_FLAGS_TYPE_MASK;
> +	switch (reply_desc_type) {
> +	case MPI3_REPLY_DESCRIPT_FLAGS_TYPE_STATUS:
> +		status_desc = (Mpi3StatusReplyDescriptor_t *)reply_desc;
> +		host_tag = le16_to_cpu(status_desc->HostTag);
> +		ioc_status = le16_to_cpu(status_desc->IOCStatus);
> +		if (ioc_status &
> +		    MPI3_REPLY_DESCRIPT_STATUS_IOCSTATUS_LOGINFOAVAIL)
> +			ioc_loginfo = le32_to_cpu(status_desc->IOCLogInfo);
> +		ioc_status &= MPI3_REPLY_DESCRIPT_STATUS_IOCSTATUS_STATUS_MASK;
> +		break;
> +	case MPI3_REPLY_DESCRIPT_FLAGS_TYPE_ADDRESS_REPLY:
> +		addr_desc = (Mpi3AddressReplyDescriptor_t *)reply_desc;
> +		*reply_dma = le64_to_cpu(addr_desc->ReplyFrameAddress);
> +		scsi_reply = mpi3mr_get_reply_virt_addr(mrioc,
> +		    *reply_dma);
> +		if (!scsi_reply) {
> +			panic("%s: scsi_reply is NULL, this shouldn't happen\n",
> +			    mrioc->name);
> +			goto out;
> +		}
> +		host_tag = le16_to_cpu(scsi_reply->HostTag);
> +		ioc_status = le16_to_cpu(scsi_reply->IOCStatus);
> +		scsi_status = scsi_reply->SCSIStatus;
> +		scsi_state = scsi_reply->SCSIState;
> +		dev_handle = le16_to_cpu(scsi_reply->DevHandle);
> +		sense_state = (scsi_state & MPI3_SCSI_STATE_SENSE_MASK);
> +		xfer_count = le32_to_cpu(scsi_reply->TransferCount);
> +		sense_count = le32_to_cpu(scsi_reply->SenseCount);
> +		resp_data = le32_to_cpu(scsi_reply->ResponseData);
> +		sense_buf = mpi3mr_get_sensebuf_virt_addr(mrioc,
> +		    le64_to_cpu(scsi_reply->SenseDataBufferAddress));
> +		if (ioc_status &
> +		    MPI3_REPLY_DESCRIPT_STATUS_IOCSTATUS_LOGINFOAVAIL)
> +			ioc_loginfo = le32_to_cpu(scsi_reply->IOCLogInfo);
> +		ioc_status &= MPI3_REPLY_DESCRIPT_STATUS_IOCSTATUS_STATUS_MASK;
> +		if (sense_state == MPI3_SCSI_STATE_SENSE_BUFF_Q_EMPTY)
> +			panic("%s: Ran out of sense buffers\n", mrioc->name);
> +		break;
> +	case MPI3_REPLY_DESCRIPT_FLAGS_TYPE_SUCCESS:
> +		success_desc = (Mpi3SuccessReplyDescriptor_t *)reply_desc;
> +		host_tag = le16_to_cpu(success_desc->HostTag);
> +		break;
> +	default:
> +		break;
> +	}
> +	scmd = mpi3mr_scmd_from_host_tag(mrioc, host_tag, qidx);
> +	if (!scmd) {
> +		panic("%s: Cannot Identify scmd for host_tag 0x%x\n",
> +		    mrioc->name, host_tag);
> +		goto out;
> +	}
> +	priv = scsi_cmd_priv(scmd);
> +	if (success_desc) {
> +		scmd->result = DID_OK << 16;
> +		goto out_success;
> +	}
> +	if (ioc_status == MPI3_IOCSTATUS_SCSI_DATA_UNDERRUN &&
> +	    xfer_count == 0 && (scsi_status == MPI3_SCSI_STATUS_BUSY ||
> +	    scsi_status == MPI3_SCSI_STATUS_RESERVATION_CONFLICT ||
> +	    scsi_status == MPI3_SCSI_STATUS_TASK_SET_FULL))
> +		ioc_status = MPI3_IOCSTATUS_SUCCESS;
> +
> +	if ((sense_state == MPI3_SCSI_STATE_SENSE_VALID) && sense_count
> +	    && sense_buf) {
> +		u32 sz = min_t(u32, SCSI_SENSE_BUFFERSIZE, sense_count);
> +
> +		memcpy(scmd->sense_buffer, sense_buf, sz);
> +	}
> +
> +	switch (ioc_status) {
> +	case MPI3_IOCSTATUS_BUSY:
> +	case MPI3_IOCSTATUS_INSUFFICIENT_RESOURCES:
> +		scmd->result = SAM_STAT_BUSY;
> +		break;
> +	case MPI3_IOCSTATUS_SCSI_DEVICE_NOT_THERE:
> +		scmd->result = DID_NO_CONNECT << 16;
> +		break;
> +	case MPI3_IOCSTATUS_SCSI_IOC_TERMINATED:
> +		scmd->result = DID_SOFT_ERROR << 16;
> +		break;
> +	case MPI3_IOCSTATUS_SCSI_TASK_TERMINATED:
> +	case MPI3_IOCSTATUS_SCSI_EXT_TERMINATED:
> +		scmd->result = DID_RESET << 16;
> +		break;
> +	case MPI3_IOCSTATUS_SCSI_RESIDUAL_MISMATCH:
> +		if ((xfer_count == 0) || (scmd->underflow > xfer_count))
> +			scmd->result = DID_SOFT_ERROR << 16;
> +		else
> +			scmd->result = (DID_OK << 16) | scsi_status;
> +		break;
> +	case MPI3_IOCSTATUS_SCSI_DATA_UNDERRUN:
> +		scmd->result = (DID_OK << 16) | scsi_status;
> +		if (sense_state == MPI3_SCSI_STATE_SENSE_VALID)
> +			break;
> +		if (xfer_count < scmd->underflow) {
> +			if (scsi_status == SAM_STAT_BUSY)
> +				scmd->result = SAM_STAT_BUSY;
> +			else
> +				scmd->result = DID_SOFT_ERROR << 16;
> +		} else if ((scsi_state & (MPI3_SCSI_STATE_NO_SCSI_STATUS))
> +		    || (sense_state != MPI3_SCSI_STATE_SENSE_NOT_AVAILABLE))
> +			scmd->result = DID_SOFT_ERROR << 16;
> +		else if (scsi_state & MPI3_SCSI_STATE_TERMINATED)
> +			scmd->result = DID_RESET << 16;
> +		else if (!xfer_count && scmd->cmnd[0] == REPORT_LUNS) {
> +			scsi_status = SAM_STAT_CHECK_CONDITION;
> +			scmd->result = (DRIVER_SENSE << 24) |
> +			    SAM_STAT_CHECK_CONDITION;
> +			scmd->sense_buffer[0] = 0x70;
> +			scmd->sense_buffer[2] = ILLEGAL_REQUEST;
> +			scmd->sense_buffer[12] = 0x20;
> +			scmd->sense_buffer[13] = 0;
> +		}
> +		break;
> +	case MPI3_IOCSTATUS_SCSI_DATA_OVERRUN:
> +		scsi_set_resid(scmd, 0);
> +		fallthrough;
> +	case MPI3_IOCSTATUS_SCSI_RECOVERED_ERROR:
> +	case MPI3_IOCSTATUS_SUCCESS:
> +		scmd->result = (DID_OK << 16) | scsi_status;
> +		if ((scsi_state & (MPI3_SCSI_STATE_NO_SCSI_STATUS))
> +			|| (sense_state == MPI3_SCSI_STATE_SENSE_FAILED)
> +			|| (sense_state == MPI3_SCSI_STATE_SENSE_BUFF_Q_EMPTY))
> +			scmd->result = DID_SOFT_ERROR << 16;
> +		else if (scsi_state & MPI3_SCSI_STATE_TERMINATED)
> +			scmd->result = DID_RESET << 16;
> +		break;
> +	case MPI3_IOCSTATUS_SCSI_PROTOCOL_ERROR:
> +	case MPI3_IOCSTATUS_INVALID_FUNCTION:
> +	case MPI3_IOCSTATUS_INVALID_SGL:
> +	case MPI3_IOCSTATUS_INTERNAL_ERROR:
> +	case MPI3_IOCSTATUS_INVALID_FIELD:
> +	case MPI3_IOCSTATUS_INVALID_STATE:
> +	case MPI3_IOCSTATUS_SCSI_IO_DATA_ERROR:
> +	case MPI3_IOCSTATUS_SCSI_TASK_MGMT_FAILED:
> +	case MPI3_IOCSTATUS_INSUFFICIENT_POWER:
> +	default:
> +		scmd->result = DID_SOFT_ERROR << 16;
> +		break;
> +	}
> +
> +	if (scmd->result != (DID_OK << 16) && (scmd->cmnd[0] != ATA_12) &&
> +	    (scmd->cmnd[0] != ATA_16)) {
> +		ioc_info(mrioc, "%s :scmd->result 0x%x\n", __func__,
> +		    scmd->result);
> +		scsi_print_command(scmd);
> +		ioc_info(mrioc,
> +		    "%s :Command issued to handle 0x%02x returned with error 0x%04x loginfo 0x%08x, qid %d\n",
> +		    __func__, dev_handle, ioc_status, ioc_loginfo,
> +		    priv->req_q_idx+1);
> +		ioc_info(mrioc,
> +		    " host_tag %d scsi_state 0x%02x scsi_status 0x%02x, xfer_cnt %d resp_data 0x%x\n",
> +		    host_tag, scsi_state, scsi_status, xfer_count, resp_data);
> +		if (sense_buf) {
> +			scsi_normalize_sense(sense_buf, sense_count, &sshdr);
> +			ioc_info(mrioc,
> +			    "%s :sense_count 0x%x, sense_key 0x%x ASC 0x%x, ASCQ 0x%x\n",
> +			    __func__, sense_count, sshdr.sense_key,
> +			    sshdr.asc, sshdr.ascq);
> +		}
> +	}
> +out_success:
> +	mpi3mr_clear_scmd_priv(mrioc, scmd);
> +	scsi_dma_unmap(scmd);
> +	scmd->scsi_done(scmd);
> +out:
> +	if (sense_buf)
> +		mpi3mr_repost_sense_buf(mrioc,
> +		    le64_to_cpu(scsi_reply->SenseDataBufferAddress));
> +}
> +
> +/**
> + * mpi3mr_get_chain_idx - get free chain buffer index
> + * @mrioc: Adapter instance reference
> + *
> + * Try to get a free chain buffer index from the free pool.
> + *
> + * Return: -1 on failure or the free chain buffer index
> + */
> +static int mpi3mr_get_chain_idx(struct mpi3mr_ioc *mrioc)
> +{
> +	u8 retry_count = 5;
> +	int cmd_idx = -1;
> +
> +	do {
> +		spin_lock(&mrioc->chain_buf_lock);
> +		cmd_idx = find_first_zero_bit(mrioc->chain_bitmap,
> +		    mrioc->chain_buf_count);
> +		if (cmd_idx < mrioc->chain_buf_count) {
> +			set_bit(cmd_idx, mrioc->chain_bitmap);
> +			spin_unlock(&mrioc->chain_buf_lock);
> +			break;
> +		}
> +		spin_unlock(&mrioc->chain_buf_lock);
> +		cmd_idx = -1;
> +	} while (retry_count--);
> +	return cmd_idx;
> +}
> +
> +/**
> + * mpi3mr_prepare_sg_scmd - build scatter gather list
> + * @mrioc: Adapter instance reference
> + * @scmd: SCSI command reference
> + * @scsiio_req: MPI3 SCSI IO request
> + *
> + * This function maps SCSI command's data and protection SGEs to
> + * MPI request SGEs. If required additional 4K chain buffer is
> + * used to send the SGEs.
> + *
> + * Return: 0 on success, -ENOMEM on dma_map_sg failure
> + */
> +static int mpi3mr_prepare_sg_scmd(struct mpi3mr_ioc *mrioc,
> +	struct scsi_cmnd *scmd, Mpi3SCSIIORequest_t *scsiio_req)
> +{
> +	dma_addr_t chain_dma;
> +	struct scatterlist *sg_scmd;
> +	void *sg_local, *chain;
> +	u32 chain_length;
> +	int sges_left, chain_idx;
> +	u32 sges_in_segment;
> +	u8 simple_sgl_flags;
> +	u8 simple_sgl_flags_last;
> +	u8 last_chain_sgl_flags;
> +	struct chain_element *chain_req;
> +	struct scmd_priv *priv = NULL;
> +
> +	priv = scsi_cmd_priv(scmd);
> +
> +	simple_sgl_flags = MPI3_SGE_FLAGS_ELEMENT_TYPE_SIMPLE |
> +	    MPI3_SGE_FLAGS_DLAS_SYSTEM;
> +	simple_sgl_flags_last = simple_sgl_flags |
> +	    MPI3_SGE_FLAGS_END_OF_LIST;
> +	last_chain_sgl_flags = MPI3_SGE_FLAGS_ELEMENT_TYPE_LAST_CHAIN |
> +	    MPI3_SGE_FLAGS_DLAS_SYSTEM;
> +
> +	sg_local = &scsiio_req->SGL;
> +
> +	if (!scsiio_req->DataLength) {
> +		mpi3mr_build_zero_len_sge(sg_local);
> +		return 0;
> +	}
> +
> +	sg_scmd = scsi_sglist(scmd);
> +	sges_left = scsi_dma_map(scmd);
> +
> +	if (sges_left < 0) {
> +		sdev_printk(KERN_ERR, scmd->device,
> +		    "scsi_dma_map failed: request for %d bytes!\n",
> +		    scsi_bufflen(scmd));
> +		return -ENOMEM;
> +	}
> +	if (sges_left > MPI3MR_SG_DEPTH) {
> +		sdev_printk(KERN_ERR, scmd->device,
> +		    "scsi_dma_map returned unsupported sge count %d!\n",
> +		    sges_left);
> +		return -ENOMEM;
> +	}
> +
> +	sges_in_segment = (mrioc->facts.op_req_sz -
> +	    offsetof(Mpi3SCSIIORequest_t, SGL))/sizeof(Mpi3SGESimple_t);
> +
> +	if (sges_left <= sges_in_segment)
> +		goto fill_in_last_segment;
> +
> +	/* fill in main message segment when there is a chain following */
> +	while (sges_in_segment > 1) {
> +		mpi3mr_add_sg_single(sg_local, simple_sgl_flags,
> +		    sg_dma_len(sg_scmd), sg_dma_address(sg_scmd));
> +		sg_scmd = sg_next(sg_scmd);
> +		sg_local += sizeof(Mpi3SGESimple_t);
> +		sges_left--;
> +		sges_in_segment--;
> +	}
> +
> +	chain_idx = mpi3mr_get_chain_idx(mrioc);
> +	if (chain_idx < 0)
> +		return -1;
> +	chain_req = &mrioc->chain_sgl_list[chain_idx];
> +	priv->chain_idx = chain_idx;
> +
> +	chain = chain_req->addr;
> +	chain_dma = chain_req->dma_addr;
> +	sges_in_segment = sges_left;
> +	chain_length = sges_in_segment * sizeof(Mpi3SGESimple_t);
> +
> +	mpi3mr_add_sg_single(sg_local, last_chain_sgl_flags,
> +	    chain_length, chain_dma);
> +
> +	sg_local = chain;
> +
> +fill_in_last_segment:
> +	while (sges_left > 0) {
> +		if (sges_left == 1)
> +			mpi3mr_add_sg_single(sg_local,
> +			    simple_sgl_flags_last, sg_dma_len(sg_scmd),
> +			    sg_dma_address(sg_scmd));
> +		else
> +			mpi3mr_add_sg_single(sg_local, simple_sgl_flags,
> +			    sg_dma_len(sg_scmd), sg_dma_address(sg_scmd));
> +		sg_scmd = sg_next(sg_scmd);
> +		sg_local += sizeof(Mpi3SGESimple_t);
> +		sges_left--;
> +	}
> +
> +	return 0;
> +}
> +
> +/**
> + * mpi3mr_build_sg_scmd - build scatter gather list for SCSI IO
> + * @mrioc: Adapter instance reference
> + * @scmd: SCSI command reference
> + * @scsiio_req: MPI3 SCSI IO request
> + *
> + * This function calls mpi3mr_prepare_sg_scmd for constructing
> + * both data SGEs and protection information SGEs in the MPI
> + * format from the SCSI Command as appropriate .
> + *
> + * Return: return value of mpi3mr_prepare_sg_scmd.
> + */
> +static int mpi3mr_build_sg_scmd(struct mpi3mr_ioc *mrioc,
> +	struct scsi_cmnd *scmd, Mpi3SCSIIORequest_t *scsiio_req)
> +{
> +	int ret;
> +
> +	ret = mpi3mr_prepare_sg_scmd(mrioc, scmd, scsiio_req);
> +	if (ret)
> +		return ret;
> +
> +	return ret;
> +}
> +
>  
>  /**
>   * mpi3mr_map_queues - Map queues callback handler
> @@ -44,6 +509,73 @@ static int mpi3mr_map_queues(struct Scsi_Host *shost)
>  	    mrioc->pdev, mrioc->op_reply_q_offset);
>  }
>  
> +/**
> + * mpi3mr_scan_start - Scan start callback handler
> + * @shost: SCSI host reference
> + *
> + * Issue port enable request asynchronously.
> + *
> + * Return: Nothing
> + */
> +static void mpi3mr_scan_start(struct Scsi_Host *shost)
> +{
> +	struct mpi3mr_ioc *mrioc = shost_priv(shost);
> +
> +	mrioc->scan_started = 1;
> +	ioc_info(mrioc, "%s :Issuing Port Enable\n", __func__);
> +	if (mpi3mr_issue_port_enable(mrioc, 1)) {
> +		ioc_err(mrioc, "%s :Issuing port enable failed\n", __func__);
> +		mrioc->scan_started = 0;
> +		mrioc->scan_failed = MPI3_IOCSTATUS_INTERNAL_ERROR;
> +	}
> +
> +}
> +
> +/**
> + * mpi3mr_scan_finished - Scan finished callback handler
> + * @shost: SCSI host reference
> + * @time: Jiffies from the scan start
> + *
> + * Checks whether the port enable is completed or timedout or
> + * failed and set the scan status accordingly after taking any
> + * recovery if required.
> + *
> + * Return: 1 on scan finished or timed out, 0 for in progress
> + */
> +static int mpi3mr_scan_finished(struct Scsi_Host *shost,
> +	unsigned long time)
> +{
> +	struct mpi3mr_ioc *mrioc = shost_priv(shost);
> +	u32 pe_timeout = MPI3MR_PORTENABLE_TIMEOUT;
> +
> +	if (time >= (pe_timeout * HZ)) {
> +		mrioc->init_cmds.is_waiting = 0;
> +		mrioc->init_cmds.callback = NULL;
> +		mrioc->init_cmds.state = MPI3MR_CMD_NOTUSED;
> +		ioc_err(mrioc, "%s :port enable request timed out\n", __func__);
> +		mrioc->is_driver_loading = 0;
> +		mpi3mr_soft_reset_handler(mrioc,
> +		    MPI3MR_RESET_FROM_PE_TIMEOUT, 1);
> +	}
> +
> +	if (mrioc->scan_failed) {
> +		ioc_err(mrioc,
> +		    "%s :port enable failed with (ioc_status=0x%08x)\n",
> +		    __func__, mrioc->scan_failed);
> +		mrioc->is_driver_loading = 0;
> +		mrioc->stop_drv_processing = 1;
> +		return 1;
> +	}
> +
> +	if (mrioc->scan_started)
> +		return 0;
> +	ioc_info(mrioc, "%s :port enable: SUCCESS\n", __func__);
> +	mrioc->is_driver_loading = 0;
> +
> +	return 1;
> +}
> +
> +
>  /**
>   * mpi3mr_slave_destroy - Slave destroy callback handler
>   * @sdev: SCSI device reference
> @@ -126,10 +658,114 @@ static int mpi3mr_target_alloc(struct scsi_target *starget)
>  static int mpi3mr_qcmd(struct Scsi_Host *shost,
>  	struct scsi_cmnd *scmd)
>  {
> +	struct mpi3mr_ioc *mrioc = shost_priv(shost);
> +	struct mpi3mr_stgt_priv_data *stgt_priv_data;
> +	struct mpi3mr_sdev_priv_data *sdev_priv_data;
> +	struct scmd_priv *scmd_priv_data = NULL;
> +	Mpi3SCSIIORequest_t *scsiio_req = NULL;
> +	struct op_req_qinfo *op_req_q = NULL;
>  	int retval = 0;
> +	u16 dev_handle;
> +	u16 host_tag;
> +	u32 scsiio_flags = 0;
> +	struct request *rq = scmd->request;
> +	int iprio_class;
> +
> +	sdev_priv_data = scmd->device->hostdata;
> +	if (!sdev_priv_data || !sdev_priv_data->tgt_priv_data) {
> +		scmd->result = DID_NO_CONNECT << 16;
> +		scmd->scsi_done(scmd);
> +		goto out;
> +	}
>  
> -	scmd->result = DID_NO_CONNECT << 16;
> -	scmd->scsi_done(scmd);
> +	if (mrioc->stop_drv_processing) {
> +		scmd->result = DID_NO_CONNECT << 16;
> +		scmd->scsi_done(scmd);
> +		goto out;
> +	}
Hi Kashyap,
for what is the above test needed (stop_drv_processing) it looks like
other drivers don't need to protect exit function in this was (for
example mpt3sas).
Regards,
Tomash

> +
> +	if (mrioc->reset_in_progress) {
> +		retval = SCSI_MLQUEUE_HOST_BUSY;
> +		goto out;
> +	}
> +
> +	stgt_priv_data = sdev_priv_data->tgt_priv_data;
> +
> +	dev_handle = stgt_priv_data->dev_handle;
> +	if (dev_handle == MPI3MR_INVALID_DEV_HANDLE) {
> +		scmd->result = DID_NO_CONNECT << 16;
> +		scmd->scsi_done(scmd);
> +		goto out;
> +	}
> +	if (stgt_priv_data->dev_removed) {
> +		scmd->result = DID_NO_CONNECT << 16;
> +		scmd->scsi_done(scmd);
> +		goto out;
> +	}
> +
> +	if (atomic_read(&stgt_priv_data->block_io)) {
> +		if (mrioc->stop_drv_processing) {
> +			scmd->result = DID_NO_CONNECT << 16;
> +			scmd->scsi_done(scmd);
> +			goto out;
> +		}
> +		retval = SCSI_MLQUEUE_DEVICE_BUSY;
> +		goto out;
> +	}
> +
> +	host_tag = mpi3mr_host_tag_for_scmd(mrioc, scmd);
> +	if (host_tag == MPI3MR_HOSTTAG_INVALID) {
> +		scmd->result = DID_ERROR << 16;
> +		scmd->scsi_done(scmd);
> +		goto out;
> +	}
> +
> +	if (scmd->sc_data_direction == DMA_FROM_DEVICE)
> +		scsiio_flags = MPI3_SCSIIO_FLAGS_DATADIRECTION_READ;
> +	else if (scmd->sc_data_direction == DMA_TO_DEVICE)
> +		scsiio_flags = MPI3_SCSIIO_FLAGS_DATADIRECTION_WRITE;
> +	else
> +		scsiio_flags = MPI3_SCSIIO_FLAGS_DATADIRECTION_NO_DATA_TRANSFER;
> +
> +	scsiio_flags |= MPI3_SCSIIO_FLAGS_TASKATTRIBUTE_SIMPLEQ;
> +
> +	if (sdev_priv_data->ncq_prio_enable) {
> +		iprio_class = IOPRIO_PRIO_CLASS(req_get_ioprio(rq));
> +		if (iprio_class == IOPRIO_CLASS_RT)
> +			scsiio_flags |= 1 << MPI3_SCSIIO_FLAGS_CMDPRI_SHIFT;
> +	}
> +
> +	if (scmd->cmd_len > 16)
> +		scsiio_flags |= MPI3_SCSIIO_FLAGS_CDB_GREATER_THAN_16;
> +
> +	scmd_priv_data = scsi_cmd_priv(scmd);
> +	memset(scmd_priv_data->mpi3mr_scsiio_req, 0, MPI3MR_ADMIN_REQ_FRAME_SZ);
> +	scsiio_req = (Mpi3SCSIIORequest_t *) scmd_priv_data->mpi3mr_scsiio_req;
> +	scsiio_req->Function = MPI3_FUNCTION_SCSI_IO;
> +	scsiio_req->HostTag = cpu_to_le16(host_tag);
> +
> +	memcpy(scsiio_req->CDB.CDB32, scmd->cmnd, scmd->cmd_len);
> +	scsiio_req->DataLength = cpu_to_le32(scsi_bufflen(scmd));
> +	scsiio_req->DevHandle = cpu_to_le16(dev_handle);
> +	scsiio_req->Flags = cpu_to_le32(scsiio_flags);
> +	int_to_scsilun(sdev_priv_data->lun_id,
> +	    (struct scsi_lun *)scsiio_req->LUN);
> +
> +	if (mpi3mr_build_sg_scmd(mrioc, scmd, scsiio_req)) {
> +		mpi3mr_clear_scmd_priv(mrioc, scmd);
> +		retval = SCSI_MLQUEUE_HOST_BUSY;
> +		goto out;
> +	}
> +	op_req_q = &mrioc->req_qinfo[scmd_priv_data->req_q_idx];
> +
> +	if (mpi3mr_op_request_post(mrioc, op_req_q,
> +	    scmd_priv_data->mpi3mr_scsiio_req)) {
> +		mpi3mr_clear_scmd_priv(mrioc, scmd);
> +		retval = SCSI_MLQUEUE_HOST_BUSY;
> +		goto out;
> +	}
> +
> +out:
>  	return retval;
>  }
>  
> @@ -143,6 +779,8 @@ static struct scsi_host_template mpi3mr_driver_template = {
>  	.slave_configure		= mpi3mr_slave_configure,
>  	.target_destroy			= mpi3mr_target_destroy,
>  	.slave_destroy			= mpi3mr_slave_destroy,
> +	.scan_finished			= mpi3mr_scan_finished,
> +	.scan_start			= mpi3mr_scan_start,
>  	.map_queues			= mpi3mr_map_queues,
>  	.no_write_same			= 1,
>  	.can_queue			= 1,
> @@ -218,6 +856,7 @@ mpi3mr_probe(struct pci_dev *pdev, const struct pci_device_id *id)
>  	spin_lock_init(&mrioc->admin_req_lock);
>  	spin_lock_init(&mrioc->reply_free_queue_lock);
>  	spin_lock_init(&mrioc->sbq_lock);
> +	spin_lock_init(&mrioc->chain_buf_lock);
>  
>  	mpi3mr_init_drv_cmd(&mrioc->init_cmds, MPI3MR_HOSTTAG_INITCMDS);
>  	if (pdev->revision)
> @@ -287,6 +926,7 @@ static void mpi3mr_remove(struct pci_dev *pdev)
>  	while (mrioc->reset_in_progress || mrioc->is_driver_loading)
>  		ssleep(1);
>  
> +	mrioc->stop_drv_processing = 1;
>  
>  	scsi_remove_host(shost);
>  
> @@ -319,6 +959,7 @@ static void mpi3mr_shutdown(struct pci_dev *pdev)
>  	mrioc = shost_priv(shost);
>  	while (mrioc->reset_in_progress || mrioc->is_driver_loading)
>  		ssleep(1);
> +	mrioc->stop_drv_processing = 1;
>  
>  	mpi3mr_cleanup_ioc(mrioc);
>  
>

Kashyap Desai Feb. 25, 2021, 1:24 p.m. UTC | #2

> >   * mpi3mr_slave_destroy - Slave destroy callback handler
> >   * @sdev: SCSI device reference
> > @@ -126,10 +658,114 @@ static int mpi3mr_target_alloc(struct
> > scsi_target *starget)  static int mpi3mr_qcmd(struct Scsi_Host *shost,
> >  	struct scsi_cmnd *scmd)
> >  {
> > +	struct mpi3mr_ioc *mrioc = shost_priv(shost);
> > +	struct mpi3mr_stgt_priv_data *stgt_priv_data;
> > +	struct mpi3mr_sdev_priv_data *sdev_priv_data;
> > +	struct scmd_priv *scmd_priv_data = NULL;
> > +	Mpi3SCSIIORequest_t *scsiio_req = NULL;
> > +	struct op_req_qinfo *op_req_q = NULL;
> >  	int retval = 0;
> > +	u16 dev_handle;
> > +	u16 host_tag;
> > +	u32 scsiio_flags = 0;
> > +	struct request *rq = scmd->request;
> > +	int iprio_class;
> > +
> > +	sdev_priv_data = scmd->device->hostdata;
> > +	if (!sdev_priv_data || !sdev_priv_data->tgt_priv_data) {
> > +		scmd->result = DID_NO_CONNECT << 16;
> > +		scmd->scsi_done(scmd);
> > +		goto out;
> > +	}
> >
> > -	scmd->result = DID_NO_CONNECT << 16;
> > -	scmd->scsi_done(scmd);
> > +	if (mrioc->stop_drv_processing) {
> > +		scmd->result = DID_NO_CONNECT << 16;
> > +		scmd->scsi_done(scmd);
> > +		goto out;
> > +	}
> Hi Kashyap,
> for what is the above test needed (stop_drv_processing) it looks like
other
> drivers don't need to protect exit function in this was (for example
mpt3sas).
Tomas, This driver code Is still under active development and I will
review this (marking as TBD).
Not only this area, but there are many more optimization possible in
mpi3mr driver.
We want to start with stable version of driver and gradually improve.
<mpi3mr> as multiple h/w queue support and mpt3sas is single queue h/w.
Due to some h/w differences we have noticed some issue are very frequent
for mp3mr vs mpt3sas.

We can opt other way around as well. We can remove this check now and when
we find the bug we can add the fix with root cause details.
Let me know if you are OK to keep this check now or add it whenever it is
required.

Kashyap

> Regards,
> Tomash

Tomas Henzl Feb. 25, 2021, 2:11 p.m. UTC | #3

On 2/25/21 2:24 PM, Kashyap Desai wrote:
>>>   * mpi3mr_slave_destroy - Slave destroy callback handler
>>>   * @sdev: SCSI device reference
>>> @@ -126,10 +658,114 @@ static int mpi3mr_target_alloc(struct
>>> scsi_target *starget)  static int mpi3mr_qcmd(struct Scsi_Host *shost,
>>>  	struct scsi_cmnd *scmd)
>>>  {
>>> +	struct mpi3mr_ioc *mrioc = shost_priv(shost);
>>> +	struct mpi3mr_stgt_priv_data *stgt_priv_data;
>>> +	struct mpi3mr_sdev_priv_data *sdev_priv_data;
>>> +	struct scmd_priv *scmd_priv_data = NULL;
>>> +	Mpi3SCSIIORequest_t *scsiio_req = NULL;
>>> +	struct op_req_qinfo *op_req_q = NULL;
>>>  	int retval = 0;
>>> +	u16 dev_handle;
>>> +	u16 host_tag;
>>> +	u32 scsiio_flags = 0;
>>> +	struct request *rq = scmd->request;
>>> +	int iprio_class;
>>> +
>>> +	sdev_priv_data = scmd->device->hostdata;
>>> +	if (!sdev_priv_data || !sdev_priv_data->tgt_priv_data) {
>>> +		scmd->result = DID_NO_CONNECT << 16;
>>> +		scmd->scsi_done(scmd);
>>> +		goto out;
>>> +	}
>>>
>>> -	scmd->result = DID_NO_CONNECT << 16;
>>> -	scmd->scsi_done(scmd);
>>> +	if (mrioc->stop_drv_processing) {
>>> +		scmd->result = DID_NO_CONNECT << 16;
>>> +		scmd->scsi_done(scmd);
>>> +		goto out;
>>> +	}
>> Hi Kashyap,
>> for what is the above test needed (stop_drv_processing) it looks like
> other
>> drivers don't need to protect exit function in this was (for example
> mpt3sas).
> Tomas, This driver code Is still under active development and I will
> review this (marking as TBD).
> Not only this area, but there are many more optimization possible in
> mpi3mr driver.
> We want to start with stable version of driver and gradually improve.
> <mpi3mr> as multiple h/w queue support and mpt3sas is single queue h/w.
> Due to some h/w differences we have noticed some issue are very frequent
> for mp3mr vs mpt3sas.
> 
> We can opt other way around as well. We can remove this check now and when
> we find the bug we can add the fix with root cause details.
> Let me know if you are OK to keep this check now or add it whenever it is
> required.

You may keep it as it is and remove later if you think that it is safer.
I was only curious how this could be triggered.


> 
> Kashyap
> 
>> Regards,
>> Tomash

Hannes Reinecke Feb. 28, 2021, 1:22 p.m. UTC | #4

On 12/22/20 11:11 AM, Kashyap Desai wrote:
> Send Port Enable Request to FW for Device Discovery.
> As part of port enable completion driver calls scan_start and
> scan_finished hooks.
> scsi layer reference like sdev, starget etc is added but actual
> device discovery will be supported once driver add complete event
> process handling (It is added in subsequent patches)
> 
> This patch provides interface which is used to interact with FW
> via operational queue pairs.
> 
> Signed-off-by: Kashyap Desai <[e-mail]>
> Cc: [e-mail]
> ---
>   drivers/scsi/mpi3mr/mpi3mr.h    |  52 +++
>   drivers/scsi/mpi3mr/mpi3mr_fw.c | 251 +++++++++++++
>   drivers/scsi/mpi3mr/mpi3mr_os.c | 645 +++++++++++++++++++++++++++++++-
>   3 files changed, 946 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/scsi/mpi3mr/mpi3mr.h b/drivers/scsi/mpi3mr/mpi3mr.h
> index fe6094bb357a..f23751e25d0f 100644
> --- a/drivers/scsi/mpi3mr/mpi3mr.h
> +++ b/drivers/scsi/mpi3mr/mpi3mr.h
> @@ -96,6 +96,7 @@ extern struct list_head mrioc_list;
>   
>   /* command/controller interaction timeout definitions in seconds */
>   #define MPI3MR_INTADMCMD_TIMEOUT		10
> +#define MPI3MR_PORTENABLE_TIMEOUT		300
>   #define MPI3MR_RESETTM_TIMEOUT			30
>   #define MPI3MR_DEFAULT_SHUTDOWN_TIME		120
>   
> @@ -312,6 +313,43 @@ struct mpi3mr_intr_info {
>   	char name[MPI3MR_NAME_LENGTH];
>   };
>   
> +/**
> + * struct mpi3mr_stgt_priv_data - SCSI target private structure
> + *
> + * @starget: Scsi_target pointer
> + * @dev_handle: FW device handle
> + * @perst_id: FW assigned Persistent ID
> + * @num_luns: Number of Logical Units
> + * @block_io: I/O blocked to the device or not
> + * @dev_removed: Device removed in the Firmware
> + * @dev_removedelay: Device is waiting to be removed in FW
> + * @dev_type: Device type
> + * @tgt_dev: Internal target device pointer
> + */
> +struct mpi3mr_stgt_priv_data {
> +	struct scsi_target *starget;
> +	u16 dev_handle;
> +	u16 perst_id;
> +	u32 num_luns;
> +	atomic_t block_io;
> +	u8 dev_removed;
> +	u8 dev_removedelay;
> +	u8 dev_type;
> +	struct mpi3mr_tgt_dev *tgt_dev;
> +};
> +
> +/**
> + * struct mpi3mr_stgt_priv_data - SCSI device private structure
> + *
> + * @tgt_priv_data: Scsi_target private data pointer
> + * @lun_id: LUN ID of the device
> + * @ncq_prio_enable: NCQ priority enable for SATA device
> + */
> +struct mpi3mr_sdev_priv_data {
> +	struct mpi3mr_stgt_priv_data *tgt_priv_data;
> +	u32 lun_id;
> +	u8 ncq_prio_enable;
> +};
>   
Why is there a separate 'lun_id' field?

>   typedef struct mpi3mr_drv_cmd DRV_CMD;
>   typedef void (*DRV_CMD_CALLBACK)(struct mpi3mr_ioc *mrioc,
> @@ -443,12 +481,16 @@ struct scmd_priv {
>    * @sbq_lock: Sense buffer queue lock
>    * @sbq_host_index: Sense buffer queuehost index
>    * @is_driver_loading: Is driver still loading
> + * @scan_started: Async scan started
> + * @scan_failed: Asycn scan failed
> + * @stop_drv_processing: Stop all command processing
>    * @max_host_ios: Maximum host I/O count
>    * @chain_buf_count: Chain buffer count
>    * @chain_buf_pool: Chain buffer pool
>    * @chain_sgl_list: Chain SGL list
>    * @chain_bitmap_sz: Chain buffer allocator bitmap size
>    * @chain_bitmap: Chain buffer allocator bitmap
> + * @chain_buf_lock: Chain buffer list lock
>    * @reset_in_progress: Reset in progress flag
>    * @unrecoverable: Controller unrecoverable flag
>    * @logging_level: Controller debug logging level
> @@ -533,6 +575,9 @@ struct mpi3mr_ioc {
>   	u32 sbq_host_index;
>   
>   	u8 is_driver_loading;
> +	u8 scan_started;
> +	u16 scan_failed;
> +	u8 stop_drv_processing;
>   
>   	u16 max_host_ios;
>   
> @@ -541,6 +586,7 @@ struct mpi3mr_ioc {
>   	struct chain_element *chain_sgl_list;
>   	u16  chain_bitmap_sz;
>   	void *chain_bitmap;
> +	spinlock_t chain_buf_lock;
>   
>   	u8 reset_in_progress;
>   	u8 unrecoverable;
> @@ -557,8 +603,11 @@ int mpi3mr_setup_resources(struct mpi3mr_ioc *mrioc);
>   void mpi3mr_cleanup_resources(struct mpi3mr_ioc *mrioc);
>   int mpi3mr_init_ioc(struct mpi3mr_ioc *mrioc);
>   void mpi3mr_cleanup_ioc(struct mpi3mr_ioc *mrioc);
> +int mpi3mr_issue_port_enable(struct mpi3mr_ioc *mrioc, u8 async);
>   int mpi3mr_admin_request_post(struct mpi3mr_ioc *mrioc, void *admin_req,
>   u16 admin_req_sz, u8 ignore_reset);
> +int mpi3mr_op_request_post(struct mpi3mr_ioc *mrioc,
> +			   struct op_req_qinfo *opreqq, u8 *req);
>   void mpi3mr_add_sg_single(void *paddr, u8 flags, u32 length,
>   			  dma_addr_t dma_addr);
>   void mpi3mr_build_zero_len_sge(void *paddr);
> @@ -569,6 +618,9 @@ void *mpi3mr_get_reply_virt_addr(struct mpi3mr_ioc *mrioc,
>   void mpi3mr_repost_sense_buf(struct mpi3mr_ioc *mrioc,
>   				     u64 sense_buf_dma);
>   
> +void mpi3mr_process_op_reply_desc(struct mpi3mr_ioc *mrioc,
> +				  Mpi3DefaultReplyDescriptor_t *reply_desc,
> +				  u64 *reply_dma, u16 qidx);
>   void mpi3mr_start_watchdog(struct mpi3mr_ioc *mrioc);
>   void mpi3mr_stop_watchdog(struct mpi3mr_ioc *mrioc);
>   
> diff --git a/drivers/scsi/mpi3mr/mpi3mr_fw.c b/drivers/scsi/mpi3mr/mpi3mr_fw.c
> index 6fb28983038e..abdf8c653e6b 100644
> --- a/drivers/scsi/mpi3mr/mpi3mr_fw.c
> +++ b/drivers/scsi/mpi3mr/mpi3mr_fw.c
> @@ -24,6 +24,23 @@ static inline void mpi3mr_writeq(__u64 b, volatile void __iomem *addr)
>   }
>   #endif
>   
> +static inline bool
> +mpi3mr_check_req_qfull(struct op_req_qinfo *op_req_q)
> +{
> +	u16 pi, ci, max_entries;
> +	bool is_qfull = false;
> +
> +	pi = op_req_q->pi;
> +	ci = op_req_q->ci;
> +	max_entries = op_req_q->num_requests;
> +
> +	if ((ci == (pi + 1)) || ((!ci) && (pi == (max_entries - 1))))
> +		is_qfull = true;
> +
> +	return is_qfull;
> +}
> + > +

This needs to be protected by a lock to ensure the 'ci' and 'pi' values 
won't change during processing; alternatively you'd need to use 
READ_ONCE() here.
Please modify or add respective lockdep annotations.

>   static void mpi3mr_sync_irqs(struct mpi3mr_ioc *mrioc)
>   {
>   	u16 i, max_vectors;
> @@ -282,6 +299,87 @@ static int mpi3mr_process_admin_reply_q(struct mpi3mr_ioc *mrioc)
>   	return num_admin_replies;
>   }
>   
> +/**
> + * mpi3mr_get_reply_desc - get reply descriptor frame corresponding to
> + *	queue's consumer index from operational reply descriptor queue.
> + * @op_reply_q: op_reply_qinfo object
> + * @reply_ci: operational reply descriptor's queue consumer index
> + *
> + * Returns reply descriptor frame address
> + */
> +static inline Mpi3DefaultReplyDescriptor_t *
> +mpi3mr_get_reply_desc(struct op_reply_qinfo *op_reply_q, u32 reply_ci)
> +{
> +	void *segment_base_addr;
> +	struct segments *segments = op_reply_q->q_segments;
> +	Mpi3DefaultReplyDescriptor_t *reply_desc = NULL;
> +
> +	segment_base_addr =
> +	    segments[reply_ci / op_reply_q->segment_qd].segment;
> +	reply_desc = (Mpi3DefaultReplyDescriptor_t *)segment_base_addr +
> +	    (reply_ci % op_reply_q->segment_qd);
> +	return reply_desc;
> +}
> +
> +
> +static int mpi3mr_process_op_reply_q(struct mpi3mr_ioc *mrioc,
> +	struct mpi3mr_intr_info *intr_info)
> +{
> +	struct op_reply_qinfo *op_reply_q = intr_info->op_reply_q;
> +	struct op_req_qinfo *op_req_q;
> +	u32 exp_phase;
> +	u32 reply_ci;
> +	u32 num_op_reply = 0;
> +	u64 reply_dma = 0;
> +	Mpi3DefaultReplyDescriptor_t *reply_desc;
> +	u16 req_q_idx = 0, reply_qidx;
> +
> +	reply_qidx = op_reply_q->qid - 1;
> +
> +	exp_phase = op_reply_q->ephase;
> +	reply_ci = op_reply_q->ci;
> +
> +	reply_desc = mpi3mr_get_reply_desc(op_reply_q, reply_ci);
> +	if ((le16_to_cpu(reply_desc->ReplyFlags) &
> +	    MPI3_REPLY_DESCRIPT_FLAGS_PHASE_MASK) != exp_phase) {
> +		return 0;
> +	}
> +
> +	do {
> +		req_q_idx = le16_to_cpu(reply_desc->RequestQueueID) - 1;
> +		op_req_q = &mrioc->req_qinfo[req_q_idx];
> +
> +		op_req_q->ci =
> +		    le16_to_cpu(reply_desc->RequestQueueCI);
> +

This introduces an interlock with request processing; from what I can 
see request processing is guarded by a spinlock, yet I don't see any 
protection here.
How do you ensure a timely update of the 'ci' value if there is parallel 
execution of requests and responses (note: you cannot always assume that 
you will have a 1:1 relationship between queuepairs, CPUs, and interrupts).
I would have expected at least a WRITE_ONCE() here.

Question is why you need to modify this at all; in most implementations 
I know of the 'ci' index is modified by firmware, as really it's the 
firmware consuming the request.
Why not here?

> +		mpi3mr_process_op_reply_desc(mrioc, reply_desc, &reply_dma,
> +		    reply_qidx);
> +		if (reply_dma)
> +			mpi3mr_repost_reply_buf(mrioc, reply_dma);
> +		num_op_reply++;
> +
> +		if (++reply_ci == op_reply_q->num_replies) {
> +			reply_ci = 0;
> +			exp_phase ^= 1;
> +		}
> +
> +		reply_desc = mpi3mr_get_reply_desc(op_reply_q, reply_ci);
> +
> +		if ((le16_to_cpu(reply_desc->ReplyFlags) &
> +		    MPI3_REPLY_DESCRIPT_FLAGS_PHASE_MASK) != exp_phase)
> +			break;
> +
> +	} while (1);
> +
> +
> +	writel(reply_ci,
> +	    &mrioc->sysif_regs->OperQueueIndexes[reply_qidx].ConsumerIndex);
> +	op_reply_q->ci = reply_ci;
> +	op_reply_q->ephase = exp_phase;
> +
> +	return num_op_reply;
> +}
> +
>   static irqreturn_t mpi3mr_isr_primary(int irq, void *privdata)
>   {
>   	struct mpi3mr_intr_info *intr_info = privdata;
> @@ -1314,6 +1412,74 @@ static int mpi3mr_create_op_queues(struct mpi3mr_ioc *mrioc)
>   	return retval;
>   }
>   
> +/**
> + * mpi3mr_op_request_post - Post request to operational queue
> + * @mrioc: Adapter reference
> + * @op_req_q: Operational request queue info
> + * @req: MPI3 request
> + *
> + * Post the MPI3 request into operational request queue and
> + * inform the controller, if the queue is full return
> + * appropriate error.
> + *
> + * Return: 0 on success, non-zero on failure.
> + */
> +int mpi3mr_op_request_post(struct mpi3mr_ioc *mrioc,
> +	struct op_req_qinfo *op_req_q, u8 *req)
> +{
> +	u16 pi = 0, max_entries, reply_qidx = 0, midx;
> +	int retval = 0;
> +	unsigned long flags;
> +	u8 *req_entry;
> +	void *segment_base_addr;
> +	u16 req_sz = mrioc->facts.op_req_sz;
> +	struct segments *segments = op_req_q->q_segments;
> +
> +	reply_qidx = op_req_q->reply_qid - 1;
> +
> +	if (mrioc->unrecoverable)
> +		return -EFAULT;
> +
> +	spin_lock_irqsave(&op_req_q->q_lock, flags);
> +	pi = op_req_q->pi;
> +	max_entries = op_req_q->num_requests;
> +
> +	if (mpi3mr_check_req_qfull(op_req_q)) {
> +		midx = REPLY_QUEUE_IDX_TO_MSIX_IDX(
> +		    reply_qidx, mrioc->op_reply_q_offset);
> +		mpi3mr_process_op_reply_q(mrioc, &mrioc->intr_info[midx]);
> +
> +		if (mpi3mr_check_req_qfull(op_req_q)) {

Ah, so here it's being used.
So do add the lockdep annotation to mpi3mr_check_req_qfull().

> +			retval = -EAGAIN;
> +			goto out;
> +		}
> +	}
> +
> +	if (mrioc->reset_in_progress) {
> +		ioc_err(mrioc, "OpReqQ submit reset in progress\n");
> +		retval = -EAGAIN;
> +		goto out;
> +	}
> +
> +	segment_base_addr = segments[pi / op_req_q->segment_qd].segment;
> +	req_entry = (u8 *)segment_base_addr +
> +	    ((pi % op_req_q->segment_qd) * req_sz);
> +
> +	memset(req_entry, 0, req_sz);
> +	memcpy(req_entry, req, MPI3MR_ADMIN_REQ_FRAME_SZ);
> +
> +	if (++pi == max_entries)
> +		pi = 0;
> +	op_req_q->pi = pi;
> +
> +	writel(op_req_q->pi,
> +	    &mrioc->sysif_regs->OperQueueIndexes[reply_qidx].ProducerIndex);
> +
> +out:
> +	spin_unlock_irqrestore(&op_req_q->q_lock, flags);
> +	return retval;
> +}
> +
>   
>   /**
>    * mpi3mr_setup_admin_qpair - Setup admin queue pair
> @@ -1901,6 +2067,91 @@ static int mpi3mr_alloc_chain_bufs(struct mpi3mr_ioc *mrioc)
>   	return retval;
>   }
>   
> +/**
> + * mpi3mr_port_enable_complete - Mark port enable complete
> + * @mrioc: Adapter instance reference
> + * @drv_cmd: Internal command tracker
> + *
> + * Call back for asynchronous port enable request sets the
> + * driver command to indicate port enable request is complete.
> + *
> + * Return: Nothing
> + */
> +static void mpi3mr_port_enable_complete(struct mpi3mr_ioc *mrioc,
> +	struct mpi3mr_drv_cmd *drv_cmd)
> +{
> +
> +	drv_cmd->state = MPI3MR_CMD_NOTUSED;
> +	drv_cmd->callback = NULL;
> +	mrioc->scan_failed = drv_cmd->ioc_status;
> +	mrioc->scan_started = 0;
> +
> +}
> +
> +/**
> + * mpi3mr_issue_port_enable - Issue Port Enable
> + * @mrioc: Adapter instance reference
> + * @async: Flag to wait for completion or not
> + *
> + * Issue Port Enable MPI request through admin queue and if the
> + * async flag is not set wait for the completion of the port
> + * enable or time out.
> + *
> + * Return: 0 on success, non-zero on failures.
> + */
> +int mpi3mr_issue_port_enable(struct mpi3mr_ioc *mrioc, u8 async)
> +{
> +	Mpi3PortEnableRequest_t pe_req;
> +	int retval = 0;
> +	u32 pe_timeout = MPI3MR_PORTENABLE_TIMEOUT;
> +
> +	memset(&pe_req, 0, sizeof(pe_req));
> +	mutex_lock(&mrioc->init_cmds.mutex);
> +	if (mrioc->init_cmds.state & MPI3MR_CMD_PENDING) {
> +		retval = -1;
> +		ioc_err(mrioc, "Issue PortEnable: Init command is in use\n");
> +		mutex_unlock(&mrioc->init_cmds.mutex);
> +		goto out;
> +	}
> +	mrioc->init_cmds.state = MPI3MR_CMD_PENDING;
> +	if (async) {
> +		mrioc->init_cmds.is_waiting = 0;
> +		mrioc->init_cmds.callback = mpi3mr_port_enable_complete;
> +	} else {
> +		mrioc->init_cmds.is_waiting = 1;
> +		mrioc->init_cmds.callback = NULL;
> +		init_completion(&mrioc->init_cmds.done);
> +	}
> +	pe_req.HostTag = cpu_to_le16(MPI3MR_HOSTTAG_INITCMDS);
> +	pe_req.Function = MPI3_FUNCTION_PORT_ENABLE;
> +
> +	retval = mpi3mr_admin_request_post(mrioc, &pe_req, sizeof(pe_req), 1);
> +	if (retval) {
> +		ioc_err(mrioc, "Issue PortEnable: Admin Post failed\n");
> +		goto out_unlock;
> +	}
> +	if (!async) {
> +		wait_for_completion_timeout(&mrioc->init_cmds.done,
> +		    (pe_timeout * HZ));
> +		if (!(mrioc->init_cmds.state & MPI3MR_CMD_COMPLETE)) {
> +			ioc_err(mrioc, "Issue PortEnable: command timed out\n");
> +			retval = -1;
> +			mrioc->scan_failed = MPI3_IOCSTATUS_INTERNAL_ERROR;
> +			mpi3mr_set_diagsave(mrioc);
> +			mpi3mr_issue_reset(mrioc,
> +			    MPI3_SYSIF_HOST_DIAG_RESET_ACTION_DIAG_FAULT,
> +			    MPI3MR_RESET_FROM_PE_TIMEOUT);
> +			mrioc->unrecoverable = 1;
> +			goto out_unlock;
> +		}
> +		mpi3mr_port_enable_complete(mrioc, &mrioc->init_cmds);
> +	}
> +out_unlock:
> +	mutex_unlock(&mrioc->init_cmds.mutex);
> +out:
> +	return retval;
> +}
> +
>   
>   /**
>    * mpi3mr_cleanup_resources - Free PCI resources
> diff --git a/drivers/scsi/mpi3mr/mpi3mr_os.c b/drivers/scsi/mpi3mr/mpi3mr_os.c
> index 3cf0be63842f..01be5f337826 100644
> --- a/drivers/scsi/mpi3mr/mpi3mr_os.c
> +++ b/drivers/scsi/mpi3mr/mpi3mr_os.c
> @@ -26,6 +26,471 @@ module_param(logging_level, int, 0);
>   MODULE_PARM_DESC(logging_level,
>   	" bits for enabling additional logging info (default=0)");
>   
> +/* Forward declarations*/
> +/**
> + * mpi3mr_host_tag_for_scmd - Get host tag for a scmd
> + * @mrioc: Adapter instance reference
> + * @scmd: SCSI command reference
> + *
> + * Calculate the host tag based on block tag for a given scmd.
> + *
> + * Return: Valid host tag or MPI3MR_HOSTTAG_INVALID.
> + */
> +static u16 mpi3mr_host_tag_for_scmd(struct mpi3mr_ioc *mrioc,
> +	struct scsi_cmnd *scmd)
> +{
> +	struct scmd_priv *priv = NULL;
> +	u32 unique_tag;
> +	u16 host_tag, hw_queue;
> +
> +	unique_tag = blk_mq_unique_tag(scmd->request);
> +
> +	hw_queue = blk_mq_unique_tag_to_hwq(unique_tag);
> +	if (hw_queue >= mrioc->num_op_reply_q)
> +		return MPI3MR_HOSTTAG_INVALID;
> +	host_tag = blk_mq_unique_tag_to_tag(unique_tag);
> +
> +	if (WARN_ON(host_tag >= mrioc->max_host_ios))
> +		return MPI3MR_HOSTTAG_INVALID;
> +
> +	priv = scsi_cmd_priv(scmd);
> +	/*host_tag 0 is invalid hence incrementing by 1*/
> +	priv->host_tag = host_tag + 1;
> +	priv->scmd = scmd;
> +	priv->in_lld_scope = 1;
> +	priv->req_q_idx = hw_queue;
> +	priv->chain_idx = -1;
> +	return priv->host_tag;
> +}
> +
> +/**
> + * mpi3mr_scmd_from_host_tag - Get SCSI command from host tag
> + * @mrioc: Adapter instance reference
> + * @host_tag: Host tag
> + * @qidx: Operational queue index
> + *
> + * Identify the block tag from the host tag and queue index and
> + * retrieve associated scsi command using scsi_host_find_tag().
> + *
> + * Return: SCSI command reference or NULL.
> + */
> +static struct scsi_cmnd *mpi3mr_scmd_from_host_tag(
> +	struct mpi3mr_ioc *mrioc, u16 host_tag, u16 qidx)
> +{
> +	struct scsi_cmnd *scmd = NULL;
> +	struct scmd_priv *priv = NULL;
> +	u32 unique_tag = host_tag - 1;
> +
> +	if (WARN_ON(host_tag > mrioc->max_host_ios))
> +		goto out;
> +
> +	unique_tag |= (qidx << BLK_MQ_UNIQUE_TAG_BITS);
> +
> +	scmd = scsi_host_find_tag(mrioc->shost, unique_tag);
> +	if (scmd) {
> +		priv = scsi_cmd_priv(scmd);
> +		if (!priv->in_lld_scope)
> +			scmd = NULL;
> +	}
> +out:
> +	return scmd;
> +}
> +
> +/**
> + * mpi3mr_clear_scmd_priv - Cleanup SCSI command private date
> + * @mrioc: Adapter instance reference
> + * @scmd: SCSI command reference
> + *
> + * Invalidate the SCSI command private data to mark the command
> + * is not in LLD scope anymore.
> + *
> + * Return: Nothing.
> + */
> +static void mpi3mr_clear_scmd_priv(struct mpi3mr_ioc *mrioc,
> +	struct scsi_cmnd *scmd)
> +{
> +	struct scmd_priv *priv = NULL;
> +
> +	priv = scsi_cmd_priv(scmd);
> +
> +	if (WARN_ON(priv->in_lld_scope == 0))
> +		return;
> +	priv->host_tag = MPI3MR_HOSTTAG_INVALID;
> +	priv->req_q_idx = 0xFFFF;
> +	priv->scmd = NULL;
> +	priv->in_lld_scope = 0;
> +	if (priv->chain_idx >= 0) {
> +		clear_bit(priv->chain_idx, mrioc->chain_bitmap);
> +		priv->chain_idx = -1;
> +	}
> +}
> +
> +/**
> + * mpi3mr_process_op_reply_desc - reply descriptor handler
> + * @mrioc: Adapter instance reference
> + * @reply_desc: Operational reply descriptor
> + * @reply_dma: place holder for reply DMA address
> + * @qidx: Operational queue index
> + *
> + * Process the operational reply descriptor and identifies the
> + * descriptor type. Based on the descriptor map the MPI3 request
> + * status to a SCSI command status and calls scsi_done call
> + * back.
> + *
> + * Return: Nothing
> + */
> +void mpi3mr_process_op_reply_desc(struct mpi3mr_ioc *mrioc,
> +	Mpi3DefaultReplyDescriptor_t *reply_desc, u64 *reply_dma, u16 qidx)
> +{
> +	u16 reply_desc_type, host_tag = 0;
> +	u16 ioc_status = MPI3_IOCSTATUS_SUCCESS;
> +	u32 ioc_loginfo = 0;
> +	Mpi3StatusReplyDescriptor_t *status_desc = NULL;
> +	Mpi3AddressReplyDescriptor_t *addr_desc = NULL;
> +	Mpi3SuccessReplyDescriptor_t *success_desc = NULL;
> +	Mpi3SCSIIOReply_t *scsi_reply = NULL;
> +	struct scsi_cmnd *scmd = NULL;
> +	struct scmd_priv *priv = NULL;
> +	u8 *sense_buf = NULL;
> +	u8 scsi_state = 0, scsi_status = 0, sense_state = 0;
> +	u32 xfer_count = 0, sense_count = 0, resp_data = 0;
> +	u16 dev_handle = 0xFFFF;
> +	struct scsi_sense_hdr sshdr;
> +
> +	*reply_dma = 0;
> +	reply_desc_type = le16_to_cpu(reply_desc->ReplyFlags) &
> +	    MPI3_REPLY_DESCRIPT_FLAGS_TYPE_MASK;
> +	switch (reply_desc_type) {
> +	case MPI3_REPLY_DESCRIPT_FLAGS_TYPE_STATUS:
> +		status_desc = (Mpi3StatusReplyDescriptor_t *)reply_desc;
> +		host_tag = le16_to_cpu(status_desc->HostTag);
> +		ioc_status = le16_to_cpu(status_desc->IOCStatus);
> +		if (ioc_status &
> +		    MPI3_REPLY_DESCRIPT_STATUS_IOCSTATUS_LOGINFOAVAIL)
> +			ioc_loginfo = le32_to_cpu(status_desc->IOCLogInfo);
> +		ioc_status &= MPI3_REPLY_DESCRIPT_STATUS_IOCSTATUS_STATUS_MASK;
> +		break;
> +	case MPI3_REPLY_DESCRIPT_FLAGS_TYPE_ADDRESS_REPLY:
> +		addr_desc = (Mpi3AddressReplyDescriptor_t *)reply_desc;
> +		*reply_dma = le64_to_cpu(addr_desc->ReplyFrameAddress);
> +		scsi_reply = mpi3mr_get_reply_virt_addr(mrioc,
> +		    *reply_dma);
> +		if (!scsi_reply) {
> +			panic("%s: scsi_reply is NULL, this shouldn't happen\n",
> +			    mrioc->name);
> +			goto out;
> +		}
> +		host_tag = le16_to_cpu(scsi_reply->HostTag);
> +		ioc_status = le16_to_cpu(scsi_reply->IOCStatus);
> +		scsi_status = scsi_reply->SCSIStatus;
> +		scsi_state = scsi_reply->SCSIState;
> +		dev_handle = le16_to_cpu(scsi_reply->DevHandle);
> +		sense_state = (scsi_state & MPI3_SCSI_STATE_SENSE_MASK);
> +		xfer_count = le32_to_cpu(scsi_reply->TransferCount);
> +		sense_count = le32_to_cpu(scsi_reply->SenseCount);
> +		resp_data = le32_to_cpu(scsi_reply->ResponseData);
> +		sense_buf = mpi3mr_get_sensebuf_virt_addr(mrioc,
> +		    le64_to_cpu(scsi_reply->SenseDataBufferAddress));
> +		if (ioc_status &
> +		    MPI3_REPLY_DESCRIPT_STATUS_IOCSTATUS_LOGINFOAVAIL)
> +			ioc_loginfo = le32_to_cpu(scsi_reply->IOCLogInfo);
> +		ioc_status &= MPI3_REPLY_DESCRIPT_STATUS_IOCSTATUS_STATUS_MASK;
> +		if (sense_state == MPI3_SCSI_STATE_SENSE_BUFF_Q_EMPTY)
> +			panic("%s: Ran out of sense buffers\n", mrioc->name);
> +		break;
> +	case MPI3_REPLY_DESCRIPT_FLAGS_TYPE_SUCCESS:
> +		success_desc = (Mpi3SuccessReplyDescriptor_t *)reply_desc;
> +		host_tag = le16_to_cpu(success_desc->HostTag);
> +		break;
> +	default:
> +		break;
> +	}
> +	scmd = mpi3mr_scmd_from_host_tag(mrioc, host_tag, qidx);
> +	if (!scmd) {
> +		panic("%s: Cannot Identify scmd for host_tag 0x%x\n",
> +		    mrioc->name, host_tag);
> +		goto out;
> +	}
> +	priv = scsi_cmd_priv(scmd);
> +	if (success_desc) {
> +		scmd->result = DID_OK << 16;
> +		goto out_success;
> +	}
> +	if (ioc_status == MPI3_IOCSTATUS_SCSI_DATA_UNDERRUN &&
> +	    xfer_count == 0 && (scsi_status == MPI3_SCSI_STATUS_BUSY ||
> +	    scsi_status == MPI3_SCSI_STATUS_RESERVATION_CONFLICT ||
> +	    scsi_status == MPI3_SCSI_STATUS_TASK_SET_FULL))
> +		ioc_status = MPI3_IOCSTATUS_SUCCESS;
> +
> +	if ((sense_state == MPI3_SCSI_STATE_SENSE_VALID) && sense_count
> +	    && sense_buf) {
> +		u32 sz = min_t(u32, SCSI_SENSE_BUFFERSIZE, sense_count);
> +
> +		memcpy(scmd->sense_buffer, sense_buf, sz);
> +	}
> +
> +	switch (ioc_status) {
> +	case MPI3_IOCSTATUS_BUSY:
> +	case MPI3_IOCSTATUS_INSUFFICIENT_RESOURCES:
> +		scmd->result = SAM_STAT_BUSY;
> +		break;
> +	case MPI3_IOCSTATUS_SCSI_DEVICE_NOT_THERE:
> +		scmd->result = DID_NO_CONNECT << 16;
> +		break;
> +	case MPI3_IOCSTATUS_SCSI_IOC_TERMINATED:
> +		scmd->result = DID_SOFT_ERROR << 16;
> +		break;
> +	case MPI3_IOCSTATUS_SCSI_TASK_TERMINATED:
> +	case MPI3_IOCSTATUS_SCSI_EXT_TERMINATED:
> +		scmd->result = DID_RESET << 16;
> +		break;
> +	case MPI3_IOCSTATUS_SCSI_RESIDUAL_MISMATCH:
> +		if ((xfer_count == 0) || (scmd->underflow > xfer_count))
> +			scmd->result = DID_SOFT_ERROR << 16;
> +		else
> +			scmd->result = (DID_OK << 16) | scsi_status;
> +		break;
> +	case MPI3_IOCSTATUS_SCSI_DATA_UNDERRUN:
> +		scmd->result = (DID_OK << 16) | scsi_status;
> +		if (sense_state == MPI3_SCSI_STATE_SENSE_VALID)
> +			break;
> +		if (xfer_count < scmd->underflow) {
> +			if (scsi_status == SAM_STAT_BUSY)
> +				scmd->result = SAM_STAT_BUSY;
> +			else
> +				scmd->result = DID_SOFT_ERROR << 16;
> +		} else if ((scsi_state & (MPI3_SCSI_STATE_NO_SCSI_STATUS))
> +		    || (sense_state != MPI3_SCSI_STATE_SENSE_NOT_AVAILABLE))
> +			scmd->result = DID_SOFT_ERROR << 16;
> +		else if (scsi_state & MPI3_SCSI_STATE_TERMINATED)
> +			scmd->result = DID_RESET << 16;
> +		else if (!xfer_count && scmd->cmnd[0] == REPORT_LUNS) {
> +			scsi_status = SAM_STAT_CHECK_CONDITION;
> +			scmd->result = (DRIVER_SENSE << 24) |
> +			    SAM_STAT_CHECK_CONDITION;
> +			scmd->sense_buffer[0] = 0x70;
> +			scmd->sense_buffer[2] = ILLEGAL_REQUEST;
> +			scmd->sense_buffer[12] = 0x20;
> +			scmd->sense_buffer[13] = 0;
> +		}
> +		break;
> +	case MPI3_IOCSTATUS_SCSI_DATA_OVERRUN:
> +		scsi_set_resid(scmd, 0);
> +		fallthrough;
> +	case MPI3_IOCSTATUS_SCSI_RECOVERED_ERROR:
> +	case MPI3_IOCSTATUS_SUCCESS:
> +		scmd->result = (DID_OK << 16) | scsi_status;
> +		if ((scsi_state & (MPI3_SCSI_STATE_NO_SCSI_STATUS))
> +			|| (sense_state == MPI3_SCSI_STATE_SENSE_FAILED)
> +			|| (sense_state == MPI3_SCSI_STATE_SENSE_BUFF_Q_EMPTY))
> +			scmd->result = DID_SOFT_ERROR << 16;
> +		else if (scsi_state & MPI3_SCSI_STATE_TERMINATED)
> +			scmd->result = DID_RESET << 16;
> +		break;
> +	case MPI3_IOCSTATUS_SCSI_PROTOCOL_ERROR:
> +	case MPI3_IOCSTATUS_INVALID_FUNCTION:
> +	case MPI3_IOCSTATUS_INVALID_SGL:
> +	case MPI3_IOCSTATUS_INTERNAL_ERROR:
> +	case MPI3_IOCSTATUS_INVALID_FIELD:
> +	case MPI3_IOCSTATUS_INVALID_STATE:
> +	case MPI3_IOCSTATUS_SCSI_IO_DATA_ERROR:
> +	case MPI3_IOCSTATUS_SCSI_TASK_MGMT_FAILED:
> +	case MPI3_IOCSTATUS_INSUFFICIENT_POWER:
> +	default:
> +		scmd->result = DID_SOFT_ERROR << 16;
> +		break;
> +	}
> +
> +	if (scmd->result != (DID_OK << 16) && (scmd->cmnd[0] != ATA_12) &&
> +	    (scmd->cmnd[0] != ATA_16)) {
> +		ioc_info(mrioc, "%s :scmd->result 0x%x\n", __func__,
> +		    scmd->result);
> +		scsi_print_command(scmd);
> +		ioc_info(mrioc,
> +		    "%s :Command issued to handle 0x%02x returned with error 0x%04x loginfo 0x%08x, qid %d\n",
> +		    __func__, dev_handle, ioc_status, ioc_loginfo,
> +		    priv->req_q_idx+1);
> +		ioc_info(mrioc,
> +		    " host_tag %d scsi_state 0x%02x scsi_status 0x%02x, xfer_cnt %d resp_data 0x%x\n",
> +		    host_tag, scsi_state, scsi_status, xfer_count, resp_data);
> +		if (sense_buf) {
> +			scsi_normalize_sense(sense_buf, sense_count, &sshdr);
> +			ioc_info(mrioc,
> +			    "%s :sense_count 0x%x, sense_key 0x%x ASC 0x%x, ASCQ 0x%x\n",
> +			    __func__, sense_count, sshdr.sense_key,
> +			    sshdr.asc, sshdr.ascq);
> +		}
> +	}
> +out_success:
> +	mpi3mr_clear_scmd_priv(mrioc, scmd);
> +	scsi_dma_unmap(scmd);
> +	scmd->scsi_done(scmd);
> +out:
> +	if (sense_buf)
> +		mpi3mr_repost_sense_buf(mrioc,
> +		    le64_to_cpu(scsi_reply->SenseDataBufferAddress));
> +}
> +
> +/**
> + * mpi3mr_get_chain_idx - get free chain buffer index
> + * @mrioc: Adapter instance reference
> + *
> + * Try to get a free chain buffer index from the free pool.
> + *
> + * Return: -1 on failure or the free chain buffer index
> + */
> +static int mpi3mr_get_chain_idx(struct mpi3mr_ioc *mrioc)
> +{
> +	u8 retry_count = 5;
> +	int cmd_idx = -1;
> +
> +	do {
> +		spin_lock(&mrioc->chain_buf_lock);
> +		cmd_idx = find_first_zero_bit(mrioc->chain_bitmap,
> +		    mrioc->chain_buf_count);
> +		if (cmd_idx < mrioc->chain_buf_count) {
> +			set_bit(cmd_idx, mrioc->chain_bitmap);
> +			spin_unlock(&mrioc->chain_buf_lock);
> +			break;
> +		}
> +		spin_unlock(&mrioc->chain_buf_lock);
> +		cmd_idx = -1;
> +	} while (retry_count--);
> +	return cmd_idx;
> +}
> +
> +/**
> + * mpi3mr_prepare_sg_scmd - build scatter gather list
> + * @mrioc: Adapter instance reference
> + * @scmd: SCSI command reference
> + * @scsiio_req: MPI3 SCSI IO request
> + *
> + * This function maps SCSI command's data and protection SGEs to
> + * MPI request SGEs. If required additional 4K chain buffer is
> + * used to send the SGEs.
> + *
> + * Return: 0 on success, -ENOMEM on dma_map_sg failure
> + */
> +static int mpi3mr_prepare_sg_scmd(struct mpi3mr_ioc *mrioc,
> +	struct scsi_cmnd *scmd, Mpi3SCSIIORequest_t *scsiio_req)
> +{
> +	dma_addr_t chain_dma;
> +	struct scatterlist *sg_scmd;
> +	void *sg_local, *chain;
> +	u32 chain_length;
> +	int sges_left, chain_idx;
> +	u32 sges_in_segment;
> +	u8 simple_sgl_flags;
> +	u8 simple_sgl_flags_last;
> +	u8 last_chain_sgl_flags;
> +	struct chain_element *chain_req;
> +	struct scmd_priv *priv = NULL;
> +
> +	priv = scsi_cmd_priv(scmd);
> +
> +	simple_sgl_flags = MPI3_SGE_FLAGS_ELEMENT_TYPE_SIMPLE |
> +	    MPI3_SGE_FLAGS_DLAS_SYSTEM;
> +	simple_sgl_flags_last = simple_sgl_flags |
> +	    MPI3_SGE_FLAGS_END_OF_LIST;
> +	last_chain_sgl_flags = MPI3_SGE_FLAGS_ELEMENT_TYPE_LAST_CHAIN |
> +	    MPI3_SGE_FLAGS_DLAS_SYSTEM;
> +
> +	sg_local = &scsiio_req->SGL;
> +
> +	if (!scsiio_req->DataLength) {
> +		mpi3mr_build_zero_len_sge(sg_local);
> +		return 0;
> +	}
> +
> +	sg_scmd = scsi_sglist(scmd);
> +	sges_left = scsi_dma_map(scmd);
> +
> +	if (sges_left < 0) {
> +		sdev_printk(KERN_ERR, scmd->device,
> +		    "scsi_dma_map failed: request for %d bytes!\n",
> +		    scsi_bufflen(scmd));
> +		return -ENOMEM;
> +	}
> +	if (sges_left > MPI3MR_SG_DEPTH) {
> +		sdev_printk(KERN_ERR, scmd->device,
> +		    "scsi_dma_map returned unsupported sge count %d!\n",
> +		    sges_left);
> +		return -ENOMEM;
> +	}
> +
> +	sges_in_segment = (mrioc->facts.op_req_sz -
> +	    offsetof(Mpi3SCSIIORequest_t, SGL))/sizeof(Mpi3SGESimple_t);
> +
> +	if (sges_left <= sges_in_segment)
> +		goto fill_in_last_segment;
> +
> +	/* fill in main message segment when there is a chain following */
> +	while (sges_in_segment > 1) {
> +		mpi3mr_add_sg_single(sg_local, simple_sgl_flags,
> +		    sg_dma_len(sg_scmd), sg_dma_address(sg_scmd));
> +		sg_scmd = sg_next(sg_scmd);
> +		sg_local += sizeof(Mpi3SGESimple_t);
> +		sges_left--;
> +		sges_in_segment--;
> +	}
> +
> +	chain_idx = mpi3mr_get_chain_idx(mrioc);
> +	if (chain_idx < 0)
> +		return -1;
> +	chain_req = &mrioc->chain_sgl_list[chain_idx];
> +	priv->chain_idx = chain_idx;
> +
> +	chain = chain_req->addr;
> +	chain_dma = chain_req->dma_addr;
> +	sges_in_segment = sges_left;
> +	chain_length = sges_in_segment * sizeof(Mpi3SGESimple_t);
> +
> +	mpi3mr_add_sg_single(sg_local, last_chain_sgl_flags,
> +	    chain_length, chain_dma);
> +
> +	sg_local = chain;
> +
> +fill_in_last_segment:
> +	while (sges_left > 0) {
> +		if (sges_left == 1)
> +			mpi3mr_add_sg_single(sg_local,
> +			    simple_sgl_flags_last, sg_dma_len(sg_scmd),
> +			    sg_dma_address(sg_scmd));
> +		else
> +			mpi3mr_add_sg_single(sg_local, simple_sgl_flags,
> +			    sg_dma_len(sg_scmd), sg_dma_address(sg_scmd));
> +		sg_scmd = sg_next(sg_scmd);
> +		sg_local += sizeof(Mpi3SGESimple_t);
> +		sges_left--;
> +	}
> +
> +	return 0;
> +}
> +
> +/**
> + * mpi3mr_build_sg_scmd - build scatter gather list for SCSI IO
> + * @mrioc: Adapter instance reference
> + * @scmd: SCSI command reference
> + * @scsiio_req: MPI3 SCSI IO request
> + *
> + * This function calls mpi3mr_prepare_sg_scmd for constructing
> + * both data SGEs and protection information SGEs in the MPI
> + * format from the SCSI Command as appropriate .
> + *
> + * Return: return value of mpi3mr_prepare_sg_scmd.
> + */
> +static int mpi3mr_build_sg_scmd(struct mpi3mr_ioc *mrioc,
> +	struct scsi_cmnd *scmd, Mpi3SCSIIORequest_t *scsiio_req)
> +{
> +	int ret;
> +
> +	ret = mpi3mr_prepare_sg_scmd(mrioc, scmd, scsiio_req);
> +	if (ret)
> +		return ret;
> +
> +	return ret;
> +}
> +
>   
>   /**
>    * mpi3mr_map_queues - Map queues callback handler
> @@ -44,6 +509,73 @@ static int mpi3mr_map_queues(struct Scsi_Host *shost)
>   	    mrioc->pdev, mrioc->op_reply_q_offset);
>   }
>   
> +/**
> + * mpi3mr_scan_start - Scan start callback handler
> + * @shost: SCSI host reference
> + *
> + * Issue port enable request asynchronously.
> + *
> + * Return: Nothing
> + */
> +static void mpi3mr_scan_start(struct Scsi_Host *shost)
> +{
> +	struct mpi3mr_ioc *mrioc = shost_priv(shost);
> +
> +	mrioc->scan_started = 1;
> +	ioc_info(mrioc, "%s :Issuing Port Enable\n", __func__);
> +	if (mpi3mr_issue_port_enable(mrioc, 1)) {
> +		ioc_err(mrioc, "%s :Issuing port enable failed\n", __func__);
> +		mrioc->scan_started = 0;
> +		mrioc->scan_failed = MPI3_IOCSTATUS_INTERNAL_ERROR;
> +	}
> +
> +}
> +
> +/**
> + * mpi3mr_scan_finished - Scan finished callback handler
> + * @shost: SCSI host reference
> + * @time: Jiffies from the scan start
> + *
> + * Checks whether the port enable is completed or timedout or
> + * failed and set the scan status accordingly after taking any
> + * recovery if required.
> + *
> + * Return: 1 on scan finished or timed out, 0 for in progress
> + */
> +static int mpi3mr_scan_finished(struct Scsi_Host *shost,
> +	unsigned long time)
> +{
> +	struct mpi3mr_ioc *mrioc = shost_priv(shost);
> +	u32 pe_timeout = MPI3MR_PORTENABLE_TIMEOUT;
> +
> +	if (time >= (pe_timeout * HZ)) {
> +		mrioc->init_cmds.is_waiting = 0;
> +		mrioc->init_cmds.callback = NULL;
> +		mrioc->init_cmds.state = MPI3MR_CMD_NOTUSED;
> +		ioc_err(mrioc, "%s :port enable request timed out\n", __func__);
> +		mrioc->is_driver_loading = 0;
> +		mpi3mr_soft_reset_handler(mrioc,
> +		    MPI3MR_RESET_FROM_PE_TIMEOUT, 1);
> +	}
> +
> +	if (mrioc->scan_failed) {
> +		ioc_err(mrioc,
> +		    "%s :port enable failed with (ioc_status=0x%08x)\n",
> +		    __func__, mrioc->scan_failed);
> +		mrioc->is_driver_loading = 0;
> +		mrioc->stop_drv_processing = 1;
> +		return 1;
> +	}
> +
> +	if (mrioc->scan_started)
> +		return 0;
> +	ioc_info(mrioc, "%s :port enable: SUCCESS\n", __func__);
> +	mrioc->is_driver_loading = 0;
> +
> +	return 1;
> +}
> +
> +
>   /**
>    * mpi3mr_slave_destroy - Slave destroy callback handler
>    * @sdev: SCSI device reference
> @@ -126,10 +658,114 @@ static int mpi3mr_target_alloc(struct scsi_target *starget)
>   static int mpi3mr_qcmd(struct Scsi_Host *shost,
>   	struct scsi_cmnd *scmd)
>   {
> +	struct mpi3mr_ioc *mrioc = shost_priv(shost);
> +	struct mpi3mr_stgt_priv_data *stgt_priv_data;
> +	struct mpi3mr_sdev_priv_data *sdev_priv_data;
> +	struct scmd_priv *scmd_priv_data = NULL;
> +	Mpi3SCSIIORequest_t *scsiio_req = NULL;
> +	struct op_req_qinfo *op_req_q = NULL;
>   	int retval = 0;
> +	u16 dev_handle;
> +	u16 host_tag;
> +	u32 scsiio_flags = 0;
> +	struct request *rq = scmd->request;
> +	int iprio_class;
> +
> +	sdev_priv_data = scmd->device->hostdata;
> +	if (!sdev_priv_data || !sdev_priv_data->tgt_priv_data) {
> +		scmd->result = DID_NO_CONNECT << 16;
> +		scmd->scsi_done(scmd);
> +		goto out;
> +	}
>   
> -	scmd->result = DID_NO_CONNECT << 16;
> -	scmd->scsi_done(scmd);
> +	if (mrioc->stop_drv_processing) {
> +		scmd->result = DID_NO_CONNECT << 16;
> +		scmd->scsi_done(scmd);
> +		goto out;
> +	}
> +
> +	if (mrioc->reset_in_progress) {
> +		retval = SCSI_MLQUEUE_HOST_BUSY;
> +		goto out;
> +	}
> +
> +	stgt_priv_data = sdev_priv_data->tgt_priv_data;
> +
> +	dev_handle = stgt_priv_data->dev_handle;
> +	if (dev_handle == MPI3MR_INVALID_DEV_HANDLE) {
> +		scmd->result = DID_NO_CONNECT << 16;
> +		scmd->scsi_done(scmd);
> +		goto out;
> +	}
> +	if (stgt_priv_data->dev_removed) {
> +		scmd->result = DID_NO_CONNECT << 16;
> +		scmd->scsi_done(scmd);
> +		goto out;
> +	}
> +
> +	if (atomic_read(&stgt_priv_data->block_io)) {
> +		if (mrioc->stop_drv_processing) {
> +			scmd->result = DID_NO_CONNECT << 16;
> +			scmd->scsi_done(scmd);
> +			goto out;
> +		}
> +		retval = SCSI_MLQUEUE_DEVICE_BUSY;
> +		goto out;
> +	}
> +
> +	host_tag = mpi3mr_host_tag_for_scmd(mrioc, scmd);
> +	if (host_tag == MPI3MR_HOSTTAG_INVALID) {
> +		scmd->result = DID_ERROR << 16;
> +		scmd->scsi_done(scmd);
> +		goto out;
> +	}
> +
> +	if (scmd->sc_data_direction == DMA_FROM_DEVICE)
> +		scsiio_flags = MPI3_SCSIIO_FLAGS_DATADIRECTION_READ;
> +	else if (scmd->sc_data_direction == DMA_TO_DEVICE)
> +		scsiio_flags = MPI3_SCSIIO_FLAGS_DATADIRECTION_WRITE;
> +	else
> +		scsiio_flags = MPI3_SCSIIO_FLAGS_DATADIRECTION_NO_DATA_TRANSFER;
> +
> +	scsiio_flags |= MPI3_SCSIIO_FLAGS_TASKATTRIBUTE_SIMPLEQ;
> +
> +	if (sdev_priv_data->ncq_prio_enable) {
> +		iprio_class = IOPRIO_PRIO_CLASS(req_get_ioprio(rq));
> +		if (iprio_class == IOPRIO_CLASS_RT)
> +			scsiio_flags |= 1 << MPI3_SCSIIO_FLAGS_CMDPRI_SHIFT;
> +	}
> +
> +	if (scmd->cmd_len > 16)
> +		scsiio_flags |= MPI3_SCSIIO_FLAGS_CDB_GREATER_THAN_16;
> +
> +	scmd_priv_data = scsi_cmd_priv(scmd);
> +	memset(scmd_priv_data->mpi3mr_scsiio_req, 0, MPI3MR_ADMIN_REQ_FRAME_SZ);
> +	scsiio_req = (Mpi3SCSIIORequest_t *) scmd_priv_data->mpi3mr_scsiio_req;
> +	scsiio_req->Function = MPI3_FUNCTION_SCSI_IO;
> +	scsiio_req->HostTag = cpu_to_le16(host_tag);
> +
> +	memcpy(scsiio_req->CDB.CDB32, scmd->cmnd, scmd->cmd_len);
> +	scsiio_req->DataLength = cpu_to_le32(scsi_bufflen(scmd));
> +	scsiio_req->DevHandle = cpu_to_le16(dev_handle);
> +	scsiio_req->Flags = cpu_to_le32(scsiio_flags);
> +	int_to_scsilun(sdev_priv_data->lun_id,
> +	    (struct scsi_lun *)scsiio_req->LUN);
> +
> +	if (mpi3mr_build_sg_scmd(mrioc, scmd, scsiio_req)) {
> +		mpi3mr_clear_scmd_priv(mrioc, scmd);
> +		retval = SCSI_MLQUEUE_HOST_BUSY;
> +		goto out;
> +	}
> +	op_req_q = &mrioc->req_qinfo[scmd_priv_data->req_q_idx];
> +
> +	if (mpi3mr_op_request_post(mrioc, op_req_q,
> +	    scmd_priv_data->mpi3mr_scsiio_req)) {
> +		mpi3mr_clear_scmd_priv(mrioc, scmd);
> +		retval = SCSI_MLQUEUE_HOST_BUSY;
> +		goto out;
> +	}
> +
> +out:
>   	return retval;
>   }
>   
> @@ -143,6 +779,8 @@ static struct scsi_host_template mpi3mr_driver_template = {
>   	.slave_configure		= mpi3mr_slave_configure,
>   	.target_destroy			= mpi3mr_target_destroy,
>   	.slave_destroy			= mpi3mr_slave_destroy,
> +	.scan_finished			= mpi3mr_scan_finished,
> +	.scan_start			= mpi3mr_scan_start,
>   	.map_queues			= mpi3mr_map_queues,
>   	.no_write_same			= 1,
>   	.can_queue			= 1,
> @@ -218,6 +856,7 @@ mpi3mr_probe(struct pci_dev *pdev, const struct pci_device_id *id)
>   	spin_lock_init(&mrioc->admin_req_lock);
>   	spin_lock_init(&mrioc->reply_free_queue_lock);
>   	spin_lock_init(&mrioc->sbq_lock);
> +	spin_lock_init(&mrioc->chain_buf_lock);
>   
>   	mpi3mr_init_drv_cmd(&mrioc->init_cmds, MPI3MR_HOSTTAG_INITCMDS);
>   	if (pdev->revision)
> @@ -287,6 +926,7 @@ static void mpi3mr_remove(struct pci_dev *pdev)
>   	while (mrioc->reset_in_progress || mrioc->is_driver_loading)
>   		ssleep(1);
>   
> +	mrioc->stop_drv_processing = 1;
>   
>   	scsi_remove_host(shost);
>   
> @@ -319,6 +959,7 @@ static void mpi3mr_shutdown(struct pci_dev *pdev)
>   	mrioc = shost_priv(shost);
>   	while (mrioc->reset_in_progress || mrioc->is_driver_loading)
>   		ssleep(1);
> +	mrioc->stop_drv_processing = 1;
>   
>   	mpi3mr_cleanup_ioc(mrioc);
>   
> 

Cheers,

Hannes

Kashyap Desai March 8, 2021, 6:25 p.m. UTC | #5

> > +
> > +/**
> > + * struct mpi3mr_stgt_priv_data - SCSI device private structure
> > + *
> > + * @tgt_priv_data: Scsi_target private data pointer
> > + * @lun_id: LUN ID of the device
> > + * @ncq_prio_enable: NCQ priority enable for SATA device  */ struct
> > +mpi3mr_sdev_priv_data {
> > +	struct mpi3mr_stgt_priv_data *tgt_priv_data;
> > +	u32 lun_id;
> > +	u8 ncq_prio_enable;
> > +};
> >
> Why is there a separate 'lun_id' field?
H/W is multi lun capable and driver store lun_id so that it can pass the
same to the FW in qcmd() and other path like task management etc.

>
> >   typedef struct mpi3mr_drv_cmd DRV_CMD;
> >   typedef void (*DRV_CMD_CALLBACK)(struct mpi3mr_ioc *mrioc, @@
> > -443,12 +481,16 @@ struct scmd_priv {
> >    * @sbq_lock: Sense buffer queue lock
> >    * @sbq_host_index: Sense buffer queuehost index
> >    * @is_driver_loading: Is driver still loading
> > + * @scan_started: Async scan started
> > + * @scan_failed: Asycn scan failed
> > + * @stop_drv_processing: Stop all command processing
> >    * @max_host_ios: Maximum host I/O count
> >    * @chain_buf_count: Chain buffer count
> >    * @chain_buf_pool: Chain buffer pool
> >    * @chain_sgl_list: Chain SGL list
> >    * @chain_bitmap_sz: Chain buffer allocator bitmap size
> >    * @chain_bitmap: Chain buffer allocator bitmap
> > + * @chain_buf_lock: Chain buffer list lock
> >    * @reset_in_progress: Reset in progress flag
> >    * @unrecoverable: Controller unrecoverable flag
> >    * @logging_level: Controller debug logging level @@ -533,6 +575,9
> > @@ struct mpi3mr_ioc {
> >   	u32 sbq_host_index;
> >
> >   	u8 is_driver_loading;
> > +	u8 scan_started;
> > +	u16 scan_failed;
> > +	u8 stop_drv_processing;
> >
> >   	u16 max_host_ios;
> >
> > @@ -541,6 +586,7 @@ struct mpi3mr_ioc {
> >   	struct chain_element *chain_sgl_list;
> >   	u16  chain_bitmap_sz;
> >   	void *chain_bitmap;
> > +	spinlock_t chain_buf_lock;
> >
> >   	u8 reset_in_progress;
> >   	u8 unrecoverable;
> > @@ -557,8 +603,11 @@ int mpi3mr_setup_resources(struct mpi3mr_ioc
> *mrioc);
> >   void mpi3mr_cleanup_resources(struct mpi3mr_ioc *mrioc);
> >   int mpi3mr_init_ioc(struct mpi3mr_ioc *mrioc);
> >   void mpi3mr_cleanup_ioc(struct mpi3mr_ioc *mrioc);
> > +int mpi3mr_issue_port_enable(struct mpi3mr_ioc *mrioc, u8 async);
> >   int mpi3mr_admin_request_post(struct mpi3mr_ioc *mrioc, void
> *admin_req,
> >   u16 admin_req_sz, u8 ignore_reset);
> > +int mpi3mr_op_request_post(struct mpi3mr_ioc *mrioc,
> > +			   struct op_req_qinfo *opreqq, u8 *req);
> >   void mpi3mr_add_sg_single(void *paddr, u8 flags, u32 length,
> >   			  dma_addr_t dma_addr);
> >   void mpi3mr_build_zero_len_sge(void *paddr); @@ -569,6 +618,9 @@
> > void *mpi3mr_get_reply_virt_addr(struct mpi3mr_ioc *mrioc,
> >   void mpi3mr_repost_sense_buf(struct mpi3mr_ioc *mrioc,
> >   				     u64 sense_buf_dma);
> >
> > +void mpi3mr_process_op_reply_desc(struct mpi3mr_ioc *mrioc,
> > +				  Mpi3DefaultReplyDescriptor_t
*reply_desc,
> > +				  u64 *reply_dma, u16 qidx);
> >   void mpi3mr_start_watchdog(struct mpi3mr_ioc *mrioc);
> >   void mpi3mr_stop_watchdog(struct mpi3mr_ioc *mrioc);
> >
> > diff --git a/drivers/scsi/mpi3mr/mpi3mr_fw.c
> > b/drivers/scsi/mpi3mr/mpi3mr_fw.c index 6fb28983038e..abdf8c653e6b
> > 100644
> > --- a/drivers/scsi/mpi3mr/mpi3mr_fw.c
> > +++ b/drivers/scsi/mpi3mr/mpi3mr_fw.c
> > @@ -24,6 +24,23 @@ static inline void mpi3mr_writeq(__u64 b, volatile
> void __iomem *addr)
> >   }
> >   #endif
> >
> > +static inline bool
> > +mpi3mr_check_req_qfull(struct op_req_qinfo *op_req_q) {
> > +	u16 pi, ci, max_entries;
> > +	bool is_qfull = false;
> > +
> > +	pi = op_req_q->pi;
> > +	ci = op_req_q->ci;
> > +	max_entries = op_req_q->num_requests;
> > +
> > +	if ((ci == (pi + 1)) || ((!ci) && (pi == (max_entries - 1))))
> > +		is_qfull = true;
> > +
> > +	return is_qfull;
> > +}
> > + > +
>
> This needs to be protected by a lock to ensure the 'ci' and 'pi' values
won't
> change during processing; alternatively you'd need to use
> READ_ONCE() here.

I will add READ_ONCE() for op_req_q->ci.

> Please modify or add respective lockdep annotations.
I will discuss with you.

>
> >   static void mpi3mr_sync_irqs(struct mpi3mr_ioc *mrioc)
> >   {
> >   	u16 i, max_vectors;
> > @@ -282,6 +299,87 @@ static int mpi3mr_process_admin_reply_q(struct
> mpi3mr_ioc *mrioc)
> >   	return num_admin_replies;
> >   }
> >
> > +/**
> > + * mpi3mr_get_reply_desc - get reply descriptor frame corresponding
to
> > + *	queue's consumer index from operational reply descriptor queue.
> > + * @op_reply_q: op_reply_qinfo object
> > + * @reply_ci: operational reply descriptor's queue consumer index
> > + *
> > + * Returns reply descriptor frame address  */ static inline
> > +Mpi3DefaultReplyDescriptor_t * mpi3mr_get_reply_desc(struct
> > +op_reply_qinfo *op_reply_q, u32 reply_ci) {
> > +	void *segment_base_addr;
> > +	struct segments *segments = op_reply_q->q_segments;
> > +	Mpi3DefaultReplyDescriptor_t *reply_desc = NULL;
> > +
> > +	segment_base_addr =
> > +	    segments[reply_ci / op_reply_q->segment_qd].segment;
> > +	reply_desc = (Mpi3DefaultReplyDescriptor_t *)segment_base_addr +
> > +	    (reply_ci % op_reply_q->segment_qd);
> > +	return reply_desc;
> > +}
> > +
> > +
> > +static int mpi3mr_process_op_reply_q(struct mpi3mr_ioc *mrioc,
> > +	struct mpi3mr_intr_info *intr_info)
> > +{
> > +	struct op_reply_qinfo *op_reply_q = intr_info->op_reply_q;
> > +	struct op_req_qinfo *op_req_q;
> > +	u32 exp_phase;
> > +	u32 reply_ci;
> > +	u32 num_op_reply = 0;
> > +	u64 reply_dma = 0;
> > +	Mpi3DefaultReplyDescriptor_t *reply_desc;
> > +	u16 req_q_idx = 0, reply_qidx;
> > +
> > +	reply_qidx = op_reply_q->qid - 1;
> > +
> > +	exp_phase = op_reply_q->ephase;
> > +	reply_ci = op_reply_q->ci;
> > +
> > +	reply_desc = mpi3mr_get_reply_desc(op_reply_q, reply_ci);
> > +	if ((le16_to_cpu(reply_desc->ReplyFlags) &
> > +	    MPI3_REPLY_DESCRIPT_FLAGS_PHASE_MASK) != exp_phase) {
> > +		return 0;
> > +	}
> > +
> > +	do {
> > +		req_q_idx = le16_to_cpu(reply_desc->RequestQueueID) - 1;
> > +		op_req_q = &mrioc->req_qinfo[req_q_idx];
> > +
> > +		op_req_q->ci =
> > +		    le16_to_cpu(reply_desc->RequestQueueCI);
> > +
>
> This introduces an interlock with request processing; from what I can
see
> request processing is guarded by a spinlock, yet I don't see any
protection
> here.
As of now there is only one path to process reply queue (from interrupt).
Going forward, blk_mq_poll interface in this driver require interlock in
this area.

> How do you ensure a timely update of the 'ci' value if there is parallel
> execution of requests and responses (note: you cannot always assume that
> you will have a 1:1 relationship between queuepairs, CPUs, and
interrupts).
> I would have expected at least a WRITE_ONCE() here.

I will add WRITE_ONCE.
>
> Question is why you need to modify this at all; in most implementations
I
> know of the 'ci' index is modified by firmware, as really it's the
firmware
> consuming the request.
> Why not here?
Each request queue need separate memory space of queue_depth for that
particular request queue. Currently we are restricting 256 queue depth for
each request queue to get better memory utilization. If we allocate each
request queue same as can_queue, we may not have require this queue_full
check (there may be some corner case, but we can work on those.).  "ci" on
request queue is updated by FW only, but driver is reading those value to
know if there are enough space to post more request. If we see frequent
queue_full with 256 queue depth, we will increase the queue_depth value in
future.

~ Kashyap

Patch

diff --git a/drivers/scsi/mpi3mr/mpi3mr.h b/drivers/scsi/mpi3mr/mpi3mr.h
index fe6094bb357a..f23751e25d0f 100644
--- a/drivers/scsi/mpi3mr/mpi3mr.h
+++ b/drivers/scsi/mpi3mr/mpi3mr.h
@@ -96,6 +96,7 @@  extern struct list_head mrioc_list;
 
 /* command/controller interaction timeout definitions in seconds */
 #define MPI3MR_INTADMCMD_TIMEOUT		10
+#define MPI3MR_PORTENABLE_TIMEOUT		300
 #define MPI3MR_RESETTM_TIMEOUT			30
 #define MPI3MR_DEFAULT_SHUTDOWN_TIME		120
 
@@ -312,6 +313,43 @@  struct mpi3mr_intr_info {
 	char name[MPI3MR_NAME_LENGTH];
 };
 
+/**
+ * struct mpi3mr_stgt_priv_data - SCSI target private structure
+ *
+ * @starget: Scsi_target pointer
+ * @dev_handle: FW device handle
+ * @perst_id: FW assigned Persistent ID
+ * @num_luns: Number of Logical Units
+ * @block_io: I/O blocked to the device or not
+ * @dev_removed: Device removed in the Firmware
+ * @dev_removedelay: Device is waiting to be removed in FW
+ * @dev_type: Device type
+ * @tgt_dev: Internal target device pointer
+ */
+struct mpi3mr_stgt_priv_data {
+	struct scsi_target *starget;
+	u16 dev_handle;
+	u16 perst_id;
+	u32 num_luns;
+	atomic_t block_io;
+	u8 dev_removed;
+	u8 dev_removedelay;
+	u8 dev_type;
+	struct mpi3mr_tgt_dev *tgt_dev;
+};
+
+/**
+ * struct mpi3mr_stgt_priv_data - SCSI device private structure
+ *
+ * @tgt_priv_data: Scsi_target private data pointer
+ * @lun_id: LUN ID of the device
+ * @ncq_prio_enable: NCQ priority enable for SATA device
+ */
+struct mpi3mr_sdev_priv_data {
+	struct mpi3mr_stgt_priv_data *tgt_priv_data;
+	u32 lun_id;
+	u8 ncq_prio_enable;
+};
 
 typedef struct mpi3mr_drv_cmd DRV_CMD;
 typedef void (*DRV_CMD_CALLBACK)(struct mpi3mr_ioc *mrioc,
@@ -443,12 +481,16 @@  struct scmd_priv {
  * @sbq_lock: Sense buffer queue lock
  * @sbq_host_index: Sense buffer queuehost index
  * @is_driver_loading: Is driver still loading
+ * @scan_started: Async scan started
+ * @scan_failed: Asycn scan failed
+ * @stop_drv_processing: Stop all command processing
  * @max_host_ios: Maximum host I/O count
  * @chain_buf_count: Chain buffer count
  * @chain_buf_pool: Chain buffer pool
  * @chain_sgl_list: Chain SGL list
  * @chain_bitmap_sz: Chain buffer allocator bitmap size
  * @chain_bitmap: Chain buffer allocator bitmap
+ * @chain_buf_lock: Chain buffer list lock
  * @reset_in_progress: Reset in progress flag
  * @unrecoverable: Controller unrecoverable flag
  * @logging_level: Controller debug logging level
@@ -533,6 +575,9 @@  struct mpi3mr_ioc {
 	u32 sbq_host_index;
 
 	u8 is_driver_loading;
+	u8 scan_started;
+	u16 scan_failed;
+	u8 stop_drv_processing;
 
 	u16 max_host_ios;
 
@@ -541,6 +586,7 @@  struct mpi3mr_ioc {
 	struct chain_element *chain_sgl_list;
 	u16  chain_bitmap_sz;
 	void *chain_bitmap;
+	spinlock_t chain_buf_lock;
 
 	u8 reset_in_progress;
 	u8 unrecoverable;
@@ -557,8 +603,11 @@  int mpi3mr_setup_resources(struct mpi3mr_ioc *mrioc);
 void mpi3mr_cleanup_resources(struct mpi3mr_ioc *mrioc);
 int mpi3mr_init_ioc(struct mpi3mr_ioc *mrioc);
 void mpi3mr_cleanup_ioc(struct mpi3mr_ioc *mrioc);
+int mpi3mr_issue_port_enable(struct mpi3mr_ioc *mrioc, u8 async);
 int mpi3mr_admin_request_post(struct mpi3mr_ioc *mrioc, void *admin_req,
 u16 admin_req_sz, u8 ignore_reset);
+int mpi3mr_op_request_post(struct mpi3mr_ioc *mrioc,
+			   struct op_req_qinfo *opreqq, u8 *req);
 void mpi3mr_add_sg_single(void *paddr, u8 flags, u32 length,
 			  dma_addr_t dma_addr);
 void mpi3mr_build_zero_len_sge(void *paddr);
@@ -569,6 +618,9 @@  void *mpi3mr_get_reply_virt_addr(struct mpi3mr_ioc *mrioc,
 void mpi3mr_repost_sense_buf(struct mpi3mr_ioc *mrioc,
 				     u64 sense_buf_dma);
 
+void mpi3mr_process_op_reply_desc(struct mpi3mr_ioc *mrioc,
+				  Mpi3DefaultReplyDescriptor_t *reply_desc,
+				  u64 *reply_dma, u16 qidx);
 void mpi3mr_start_watchdog(struct mpi3mr_ioc *mrioc);
 void mpi3mr_stop_watchdog(struct mpi3mr_ioc *mrioc);
 
diff --git a/drivers/scsi/mpi3mr/mpi3mr_fw.c b/drivers/scsi/mpi3mr/mpi3mr_fw.c
index 6fb28983038e..abdf8c653e6b 100644
--- a/drivers/scsi/mpi3mr/mpi3mr_fw.c
+++ b/drivers/scsi/mpi3mr/mpi3mr_fw.c
@@ -24,6 +24,23 @@  static inline void mpi3mr_writeq(__u64 b, volatile void __iomem *addr)
 }
 #endif
 
+static inline bool
+mpi3mr_check_req_qfull(struct op_req_qinfo *op_req_q)
+{
+	u16 pi, ci, max_entries;
+	bool is_qfull = false;
+
+	pi = op_req_q->pi;
+	ci = op_req_q->ci;
+	max_entries = op_req_q->num_requests;
+
+	if ((ci == (pi + 1)) || ((!ci) && (pi == (max_entries - 1))))
+		is_qfull = true;
+
+	return is_qfull;
+}
+
+
 static void mpi3mr_sync_irqs(struct mpi3mr_ioc *mrioc)
 {
 	u16 i, max_vectors;
@@ -282,6 +299,87 @@  static int mpi3mr_process_admin_reply_q(struct mpi3mr_ioc *mrioc)
 	return num_admin_replies;
 }
 
+/**
+ * mpi3mr_get_reply_desc - get reply descriptor frame corresponding to
+ *	queue's consumer index from operational reply descriptor queue.
+ * @op_reply_q: op_reply_qinfo object
+ * @reply_ci: operational reply descriptor's queue consumer index
+ *
+ * Returns reply descriptor frame address
+ */
+static inline Mpi3DefaultReplyDescriptor_t *
+mpi3mr_get_reply_desc(struct op_reply_qinfo *op_reply_q, u32 reply_ci)
+{
+	void *segment_base_addr;
+	struct segments *segments = op_reply_q->q_segments;
+	Mpi3DefaultReplyDescriptor_t *reply_desc = NULL;
+
+	segment_base_addr =
+	    segments[reply_ci / op_reply_q->segment_qd].segment;
+	reply_desc = (Mpi3DefaultReplyDescriptor_t *)segment_base_addr +
+	    (reply_ci % op_reply_q->segment_qd);
+	return reply_desc;
+}
+
+
+static int mpi3mr_process_op_reply_q(struct mpi3mr_ioc *mrioc,
+	struct mpi3mr_intr_info *intr_info)
+{
+	struct op_reply_qinfo *op_reply_q = intr_info->op_reply_q;
+	struct op_req_qinfo *op_req_q;
+	u32 exp_phase;
+	u32 reply_ci;
+	u32 num_op_reply = 0;
+	u64 reply_dma = 0;
+	Mpi3DefaultReplyDescriptor_t *reply_desc;
+	u16 req_q_idx = 0, reply_qidx;
+
+	reply_qidx = op_reply_q->qid - 1;
+
+	exp_phase = op_reply_q->ephase;
+	reply_ci = op_reply_q->ci;
+
+	reply_desc = mpi3mr_get_reply_desc(op_reply_q, reply_ci);
+	if ((le16_to_cpu(reply_desc->ReplyFlags) &
+	    MPI3_REPLY_DESCRIPT_FLAGS_PHASE_MASK) != exp_phase) {
+		return 0;
+	}
+
+	do {
+		req_q_idx = le16_to_cpu(reply_desc->RequestQueueID) - 1;
+		op_req_q = &mrioc->req_qinfo[req_q_idx];
+
+		op_req_q->ci =
+		    le16_to_cpu(reply_desc->RequestQueueCI);
+
+		mpi3mr_process_op_reply_desc(mrioc, reply_desc, &reply_dma,
+		    reply_qidx);
+		if (reply_dma)
+			mpi3mr_repost_reply_buf(mrioc, reply_dma);
+		num_op_reply++;
+
+		if (++reply_ci == op_reply_q->num_replies) {
+			reply_ci = 0;
+			exp_phase ^= 1;
+		}
+
+		reply_desc = mpi3mr_get_reply_desc(op_reply_q, reply_ci);
+
+		if ((le16_to_cpu(reply_desc->ReplyFlags) &
+		    MPI3_REPLY_DESCRIPT_FLAGS_PHASE_MASK) != exp_phase)
+			break;
+
+	} while (1);
+
+
+	writel(reply_ci,
+	    &mrioc->sysif_regs->OperQueueIndexes[reply_qidx].ConsumerIndex);
+	op_reply_q->ci = reply_ci;
+	op_reply_q->ephase = exp_phase;
+
+	return num_op_reply;
+}
+
 static irqreturn_t mpi3mr_isr_primary(int irq, void *privdata)
 {
 	struct mpi3mr_intr_info *intr_info = privdata;
@@ -1314,6 +1412,74 @@  static int mpi3mr_create_op_queues(struct mpi3mr_ioc *mrioc)
 	return retval;
 }
 
+/**
+ * mpi3mr_op_request_post - Post request to operational queue
+ * @mrioc: Adapter reference
+ * @op_req_q: Operational request queue info
+ * @req: MPI3 request
+ *
+ * Post the MPI3 request into operational request queue and
+ * inform the controller, if the queue is full return
+ * appropriate error.
+ *
+ * Return: 0 on success, non-zero on failure.
+ */
+int mpi3mr_op_request_post(struct mpi3mr_ioc *mrioc,
+	struct op_req_qinfo *op_req_q, u8 *req)
+{
+	u16 pi = 0, max_entries, reply_qidx = 0, midx;
+	int retval = 0;
+	unsigned long flags;
+	u8 *req_entry;
+	void *segment_base_addr;
+	u16 req_sz = mrioc->facts.op_req_sz;
+	struct segments *segments = op_req_q->q_segments;
+
+	reply_qidx = op_req_q->reply_qid - 1;
+
+	if (mrioc->unrecoverable)
+		return -EFAULT;
+
+	spin_lock_irqsave(&op_req_q->q_lock, flags);
+	pi = op_req_q->pi;
+	max_entries = op_req_q->num_requests;
+
+	if (mpi3mr_check_req_qfull(op_req_q)) {
+		midx = REPLY_QUEUE_IDX_TO_MSIX_IDX(
+		    reply_qidx, mrioc->op_reply_q_offset);
+		mpi3mr_process_op_reply_q(mrioc, &mrioc->intr_info[midx]);
+
+		if (mpi3mr_check_req_qfull(op_req_q)) {
+			retval = -EAGAIN;
+			goto out;
+		}
+	}
+
+	if (mrioc->reset_in_progress) {
+		ioc_err(mrioc, "OpReqQ submit reset in progress\n");
+		retval = -EAGAIN;
+		goto out;
+	}
+
+	segment_base_addr = segments[pi / op_req_q->segment_qd].segment;
+	req_entry = (u8 *)segment_base_addr +
+	    ((pi % op_req_q->segment_qd) * req_sz);
+
+	memset(req_entry, 0, req_sz);
+	memcpy(req_entry, req, MPI3MR_ADMIN_REQ_FRAME_SZ);
+
+	if (++pi == max_entries)
+		pi = 0;
+	op_req_q->pi = pi;
+
+	writel(op_req_q->pi,
+	    &mrioc->sysif_regs->OperQueueIndexes[reply_qidx].ProducerIndex);
+
+out:
+	spin_unlock_irqrestore(&op_req_q->q_lock, flags);
+	return retval;
+}
+
 
 /**
  * mpi3mr_setup_admin_qpair - Setup admin queue pair
@@ -1901,6 +2067,91 @@  static int mpi3mr_alloc_chain_bufs(struct mpi3mr_ioc *mrioc)
 	return retval;
 }
 
+/**
+ * mpi3mr_port_enable_complete - Mark port enable complete
+ * @mrioc: Adapter instance reference
+ * @drv_cmd: Internal command tracker
+ *
+ * Call back for asynchronous port enable request sets the
+ * driver command to indicate port enable request is complete.
+ *
+ * Return: Nothing
+ */
+static void mpi3mr_port_enable_complete(struct mpi3mr_ioc *mrioc,
+	struct mpi3mr_drv_cmd *drv_cmd)
+{
+
+	drv_cmd->state = MPI3MR_CMD_NOTUSED;
+	drv_cmd->callback = NULL;
+	mrioc->scan_failed = drv_cmd->ioc_status;
+	mrioc->scan_started = 0;
+
+}
+
+/**
+ * mpi3mr_issue_port_enable - Issue Port Enable
+ * @mrioc: Adapter instance reference
+ * @async: Flag to wait for completion or not
+ *
+ * Issue Port Enable MPI request through admin queue and if the
+ * async flag is not set wait for the completion of the port
+ * enable or time out.
+ *
+ * Return: 0 on success, non-zero on failures.
+ */
+int mpi3mr_issue_port_enable(struct mpi3mr_ioc *mrioc, u8 async)
+{
+	Mpi3PortEnableRequest_t pe_req;
+	int retval = 0;
+	u32 pe_timeout = MPI3MR_PORTENABLE_TIMEOUT;
+
+	memset(&pe_req, 0, sizeof(pe_req));
+	mutex_lock(&mrioc->init_cmds.mutex);
+	if (mrioc->init_cmds.state & MPI3MR_CMD_PENDING) {
+		retval = -1;
+		ioc_err(mrioc, "Issue PortEnable: Init command is in use\n");
+		mutex_unlock(&mrioc->init_cmds.mutex);
+		goto out;
+	}
+	mrioc->init_cmds.state = MPI3MR_CMD_PENDING;
+	if (async) {
+		mrioc->init_cmds.is_waiting = 0;
+		mrioc->init_cmds.callback = mpi3mr_port_enable_complete;
+	} else {
+		mrioc->init_cmds.is_waiting = 1;
+		mrioc->init_cmds.callback = NULL;
+		init_completion(&mrioc->init_cmds.done);
+	}
+	pe_req.HostTag = cpu_to_le16(MPI3MR_HOSTTAG_INITCMDS);
+	pe_req.Function = MPI3_FUNCTION_PORT_ENABLE;
+
+	retval = mpi3mr_admin_request_post(mrioc, &pe_req, sizeof(pe_req), 1);
+	if (retval) {
+		ioc_err(mrioc, "Issue PortEnable: Admin Post failed\n");
+		goto out_unlock;
+	}
+	if (!async) {
+		wait_for_completion_timeout(&mrioc->init_cmds.done,
+		    (pe_timeout * HZ));
+		if (!(mrioc->init_cmds.state & MPI3MR_CMD_COMPLETE)) {
+			ioc_err(mrioc, "Issue PortEnable: command timed out\n");
+			retval = -1;
+			mrioc->scan_failed = MPI3_IOCSTATUS_INTERNAL_ERROR;
+			mpi3mr_set_diagsave(mrioc);
+			mpi3mr_issue_reset(mrioc,
+			    MPI3_SYSIF_HOST_DIAG_RESET_ACTION_DIAG_FAULT,
+			    MPI3MR_RESET_FROM_PE_TIMEOUT);
+			mrioc->unrecoverable = 1;
+			goto out_unlock;
+		}
+		mpi3mr_port_enable_complete(mrioc, &mrioc->init_cmds);
+	}
+out_unlock:
+	mutex_unlock(&mrioc->init_cmds.mutex);
+out:
+	return retval;
+}
+
 
 /**
  * mpi3mr_cleanup_resources - Free PCI resources
diff --git a/drivers/scsi/mpi3mr/mpi3mr_os.c b/drivers/scsi/mpi3mr/mpi3mr_os.c
index 3cf0be63842f..01be5f337826 100644
--- a/drivers/scsi/mpi3mr/mpi3mr_os.c
+++ b/drivers/scsi/mpi3mr/mpi3mr_os.c
@@ -26,6 +26,471 @@  module_param(logging_level, int, 0);
 MODULE_PARM_DESC(logging_level,
 	" bits for enabling additional logging info (default=0)");
 
+/* Forward declarations*/
+/**
+ * mpi3mr_host_tag_for_scmd - Get host tag for a scmd
+ * @mrioc: Adapter instance reference
+ * @scmd: SCSI command reference
+ *
+ * Calculate the host tag based on block tag for a given scmd.
+ *
+ * Return: Valid host tag or MPI3MR_HOSTTAG_INVALID.
+ */
+static u16 mpi3mr_host_tag_for_scmd(struct mpi3mr_ioc *mrioc,
+	struct scsi_cmnd *scmd)
+{
+	struct scmd_priv *priv = NULL;
+	u32 unique_tag;
+	u16 host_tag, hw_queue;
+
+	unique_tag = blk_mq_unique_tag(scmd->request);
+
+	hw_queue = blk_mq_unique_tag_to_hwq(unique_tag);
+	if (hw_queue >= mrioc->num_op_reply_q)
+		return MPI3MR_HOSTTAG_INVALID;
+	host_tag = blk_mq_unique_tag_to_tag(unique_tag);
+
+	if (WARN_ON(host_tag >= mrioc->max_host_ios))
+		return MPI3MR_HOSTTAG_INVALID;
+
+	priv = scsi_cmd_priv(scmd);
+	/*host_tag 0 is invalid hence incrementing by 1*/
+	priv->host_tag = host_tag + 1;
+	priv->scmd = scmd;
+	priv->in_lld_scope = 1;
+	priv->req_q_idx = hw_queue;
+	priv->chain_idx = -1;
+	return priv->host_tag;
+}
+
+/**
+ * mpi3mr_scmd_from_host_tag - Get SCSI command from host tag
+ * @mrioc: Adapter instance reference
+ * @host_tag: Host tag
+ * @qidx: Operational queue index
+ *
+ * Identify the block tag from the host tag and queue index and
+ * retrieve associated scsi command using scsi_host_find_tag().
+ *
+ * Return: SCSI command reference or NULL.
+ */
+static struct scsi_cmnd *mpi3mr_scmd_from_host_tag(
+	struct mpi3mr_ioc *mrioc, u16 host_tag, u16 qidx)
+{
+	struct scsi_cmnd *scmd = NULL;
+	struct scmd_priv *priv = NULL;
+	u32 unique_tag = host_tag - 1;
+
+	if (WARN_ON(host_tag > mrioc->max_host_ios))
+		goto out;
+
+	unique_tag |= (qidx << BLK_MQ_UNIQUE_TAG_BITS);
+
+	scmd = scsi_host_find_tag(mrioc->shost, unique_tag);
+	if (scmd) {
+		priv = scsi_cmd_priv(scmd);
+		if (!priv->in_lld_scope)
+			scmd = NULL;
+	}
+out:
+	return scmd;
+}
+
+/**
+ * mpi3mr_clear_scmd_priv - Cleanup SCSI command private date
+ * @mrioc: Adapter instance reference
+ * @scmd: SCSI command reference
+ *
+ * Invalidate the SCSI command private data to mark the command
+ * is not in LLD scope anymore.
+ *
+ * Return: Nothing.
+ */
+static void mpi3mr_clear_scmd_priv(struct mpi3mr_ioc *mrioc,
+	struct scsi_cmnd *scmd)
+{
+	struct scmd_priv *priv = NULL;
+
+	priv = scsi_cmd_priv(scmd);
+
+	if (WARN_ON(priv->in_lld_scope == 0))
+		return;
+	priv->host_tag = MPI3MR_HOSTTAG_INVALID;
+	priv->req_q_idx = 0xFFFF;
+	priv->scmd = NULL;
+	priv->in_lld_scope = 0;
+	if (priv->chain_idx >= 0) {
+		clear_bit(priv->chain_idx, mrioc->chain_bitmap);
+		priv->chain_idx = -1;
+	}
+}
+
+/**
+ * mpi3mr_process_op_reply_desc - reply descriptor handler
+ * @mrioc: Adapter instance reference
+ * @reply_desc: Operational reply descriptor
+ * @reply_dma: place holder for reply DMA address
+ * @qidx: Operational queue index
+ *
+ * Process the operational reply descriptor and identifies the
+ * descriptor type. Based on the descriptor map the MPI3 request
+ * status to a SCSI command status and calls scsi_done call
+ * back.
+ *
+ * Return: Nothing
+ */
+void mpi3mr_process_op_reply_desc(struct mpi3mr_ioc *mrioc,
+	Mpi3DefaultReplyDescriptor_t *reply_desc, u64 *reply_dma, u16 qidx)
+{
+	u16 reply_desc_type, host_tag = 0;
+	u16 ioc_status = MPI3_IOCSTATUS_SUCCESS;
+	u32 ioc_loginfo = 0;
+	Mpi3StatusReplyDescriptor_t *status_desc = NULL;
+	Mpi3AddressReplyDescriptor_t *addr_desc = NULL;
+	Mpi3SuccessReplyDescriptor_t *success_desc = NULL;
+	Mpi3SCSIIOReply_t *scsi_reply = NULL;
+	struct scsi_cmnd *scmd = NULL;
+	struct scmd_priv *priv = NULL;
+	u8 *sense_buf = NULL;
+	u8 scsi_state = 0, scsi_status = 0, sense_state = 0;
+	u32 xfer_count = 0, sense_count = 0, resp_data = 0;
+	u16 dev_handle = 0xFFFF;
+	struct scsi_sense_hdr sshdr;
+
+	*reply_dma = 0;
+	reply_desc_type = le16_to_cpu(reply_desc->ReplyFlags) &
+	    MPI3_REPLY_DESCRIPT_FLAGS_TYPE_MASK;
+	switch (reply_desc_type) {
+	case MPI3_REPLY_DESCRIPT_FLAGS_TYPE_STATUS:
+		status_desc = (Mpi3StatusReplyDescriptor_t *)reply_desc;
+		host_tag = le16_to_cpu(status_desc->HostTag);
+		ioc_status = le16_to_cpu(status_desc->IOCStatus);
+		if (ioc_status &
+		    MPI3_REPLY_DESCRIPT_STATUS_IOCSTATUS_LOGINFOAVAIL)
+			ioc_loginfo = le32_to_cpu(status_desc->IOCLogInfo);
+		ioc_status &= MPI3_REPLY_DESCRIPT_STATUS_IOCSTATUS_STATUS_MASK;
+		break;
+	case MPI3_REPLY_DESCRIPT_FLAGS_TYPE_ADDRESS_REPLY:
+		addr_desc = (Mpi3AddressReplyDescriptor_t *)reply_desc;
+		*reply_dma = le64_to_cpu(addr_desc->ReplyFrameAddress);
+		scsi_reply = mpi3mr_get_reply_virt_addr(mrioc,
+		    *reply_dma);
+		if (!scsi_reply) {
+			panic("%s: scsi_reply is NULL, this shouldn't happen\n",
+			    mrioc->name);
+			goto out;
+		}
+		host_tag = le16_to_cpu(scsi_reply->HostTag);
+		ioc_status = le16_to_cpu(scsi_reply->IOCStatus);
+		scsi_status = scsi_reply->SCSIStatus;
+		scsi_state = scsi_reply->SCSIState;
+		dev_handle = le16_to_cpu(scsi_reply->DevHandle);
+		sense_state = (scsi_state & MPI3_SCSI_STATE_SENSE_MASK);
+		xfer_count = le32_to_cpu(scsi_reply->TransferCount);
+		sense_count = le32_to_cpu(scsi_reply->SenseCount);
+		resp_data = le32_to_cpu(scsi_reply->ResponseData);
+		sense_buf = mpi3mr_get_sensebuf_virt_addr(mrioc,
+		    le64_to_cpu(scsi_reply->SenseDataBufferAddress));
+		if (ioc_status &
+		    MPI3_REPLY_DESCRIPT_STATUS_IOCSTATUS_LOGINFOAVAIL)
+			ioc_loginfo = le32_to_cpu(scsi_reply->IOCLogInfo);
+		ioc_status &= MPI3_REPLY_DESCRIPT_STATUS_IOCSTATUS_STATUS_MASK;
+		if (sense_state == MPI3_SCSI_STATE_SENSE_BUFF_Q_EMPTY)
+			panic("%s: Ran out of sense buffers\n", mrioc->name);
+		break;
+	case MPI3_REPLY_DESCRIPT_FLAGS_TYPE_SUCCESS:
+		success_desc = (Mpi3SuccessReplyDescriptor_t *)reply_desc;
+		host_tag = le16_to_cpu(success_desc->HostTag);
+		break;
+	default:
+		break;
+	}
+	scmd = mpi3mr_scmd_from_host_tag(mrioc, host_tag, qidx);
+	if (!scmd) {
+		panic("%s: Cannot Identify scmd for host_tag 0x%x\n",
+		    mrioc->name, host_tag);
+		goto out;
+	}
+	priv = scsi_cmd_priv(scmd);
+	if (success_desc) {
+		scmd->result = DID_OK << 16;
+		goto out_success;
+	}
+	if (ioc_status == MPI3_IOCSTATUS_SCSI_DATA_UNDERRUN &&
+	    xfer_count == 0 && (scsi_status == MPI3_SCSI_STATUS_BUSY ||
+	    scsi_status == MPI3_SCSI_STATUS_RESERVATION_CONFLICT ||
+	    scsi_status == MPI3_SCSI_STATUS_TASK_SET_FULL))
+		ioc_status = MPI3_IOCSTATUS_SUCCESS;
+
+	if ((sense_state == MPI3_SCSI_STATE_SENSE_VALID) && sense_count
+	    && sense_buf) {
+		u32 sz = min_t(u32, SCSI_SENSE_BUFFERSIZE, sense_count);
+
+		memcpy(scmd->sense_buffer, sense_buf, sz);
+	}
+
+	switch (ioc_status) {
+	case MPI3_IOCSTATUS_BUSY:
+	case MPI3_IOCSTATUS_INSUFFICIENT_RESOURCES:
+		scmd->result = SAM_STAT_BUSY;
+		break;
+	case MPI3_IOCSTATUS_SCSI_DEVICE_NOT_THERE:
+		scmd->result = DID_NO_CONNECT << 16;
+		break;
+	case MPI3_IOCSTATUS_SCSI_IOC_TERMINATED:
+		scmd->result = DID_SOFT_ERROR << 16;
+		break;
+	case MPI3_IOCSTATUS_SCSI_TASK_TERMINATED:
+	case MPI3_IOCSTATUS_SCSI_EXT_TERMINATED:
+		scmd->result = DID_RESET << 16;
+		break;
+	case MPI3_IOCSTATUS_SCSI_RESIDUAL_MISMATCH:
+		if ((xfer_count == 0) || (scmd->underflow > xfer_count))
+			scmd->result = DID_SOFT_ERROR << 16;
+		else
+			scmd->result = (DID_OK << 16) | scsi_status;
+		break;
+	case MPI3_IOCSTATUS_SCSI_DATA_UNDERRUN:
+		scmd->result = (DID_OK << 16) | scsi_status;
+		if (sense_state == MPI3_SCSI_STATE_SENSE_VALID)
+			break;
+		if (xfer_count < scmd->underflow) {
+			if (scsi_status == SAM_STAT_BUSY)
+				scmd->result = SAM_STAT_BUSY;
+			else
+				scmd->result = DID_SOFT_ERROR << 16;
+		} else if ((scsi_state & (MPI3_SCSI_STATE_NO_SCSI_STATUS))
+		    || (sense_state != MPI3_SCSI_STATE_SENSE_NOT_AVAILABLE))
+			scmd->result = DID_SOFT_ERROR << 16;
+		else if (scsi_state & MPI3_SCSI_STATE_TERMINATED)
+			scmd->result = DID_RESET << 16;
+		else if (!xfer_count && scmd->cmnd[0] == REPORT_LUNS) {
+			scsi_status = SAM_STAT_CHECK_CONDITION;
+			scmd->result = (DRIVER_SENSE << 24) |
+			    SAM_STAT_CHECK_CONDITION;
+			scmd->sense_buffer[0] = 0x70;
+			scmd->sense_buffer[2] = ILLEGAL_REQUEST;
+			scmd->sense_buffer[12] = 0x20;
+			scmd->sense_buffer[13] = 0;
+		}
+		break;
+	case MPI3_IOCSTATUS_SCSI_DATA_OVERRUN:
+		scsi_set_resid(scmd, 0);
+		fallthrough;
+	case MPI3_IOCSTATUS_SCSI_RECOVERED_ERROR:
+	case MPI3_IOCSTATUS_SUCCESS:
+		scmd->result = (DID_OK << 16) | scsi_status;
+		if ((scsi_state & (MPI3_SCSI_STATE_NO_SCSI_STATUS))
+			|| (sense_state == MPI3_SCSI_STATE_SENSE_FAILED)
+			|| (sense_state == MPI3_SCSI_STATE_SENSE_BUFF_Q_EMPTY))
+			scmd->result = DID_SOFT_ERROR << 16;
+		else if (scsi_state & MPI3_SCSI_STATE_TERMINATED)
+			scmd->result = DID_RESET << 16;
+		break;
+	case MPI3_IOCSTATUS_SCSI_PROTOCOL_ERROR:
+	case MPI3_IOCSTATUS_INVALID_FUNCTION:
+	case MPI3_IOCSTATUS_INVALID_SGL:
+	case MPI3_IOCSTATUS_INTERNAL_ERROR:
+	case MPI3_IOCSTATUS_INVALID_FIELD:
+	case MPI3_IOCSTATUS_INVALID_STATE:
+	case MPI3_IOCSTATUS_SCSI_IO_DATA_ERROR:
+	case MPI3_IOCSTATUS_SCSI_TASK_MGMT_FAILED:
+	case MPI3_IOCSTATUS_INSUFFICIENT_POWER:
+	default:
+		scmd->result = DID_SOFT_ERROR << 16;
+		break;
+	}
+
+	if (scmd->result != (DID_OK << 16) && (scmd->cmnd[0] != ATA_12) &&
+	    (scmd->cmnd[0] != ATA_16)) {
+		ioc_info(mrioc, "%s :scmd->result 0x%x\n", __func__,
+		    scmd->result);
+		scsi_print_command(scmd);
+		ioc_info(mrioc,
+		    "%s :Command issued to handle 0x%02x returned with error 0x%04x loginfo 0x%08x, qid %d\n",
+		    __func__, dev_handle, ioc_status, ioc_loginfo,
+		    priv->req_q_idx+1);
+		ioc_info(mrioc,
+		    " host_tag %d scsi_state 0x%02x scsi_status 0x%02x, xfer_cnt %d resp_data 0x%x\n",
+		    host_tag, scsi_state, scsi_status, xfer_count, resp_data);
+		if (sense_buf) {
+			scsi_normalize_sense(sense_buf, sense_count, &sshdr);
+			ioc_info(mrioc,
+			    "%s :sense_count 0x%x, sense_key 0x%x ASC 0x%x, ASCQ 0x%x\n",
+			    __func__, sense_count, sshdr.sense_key,
+			    sshdr.asc, sshdr.ascq);
+		}
+	}
+out_success:
+	mpi3mr_clear_scmd_priv(mrioc, scmd);
+	scsi_dma_unmap(scmd);
+	scmd->scsi_done(scmd);
+out:
+	if (sense_buf)
+		mpi3mr_repost_sense_buf(mrioc,
+		    le64_to_cpu(scsi_reply->SenseDataBufferAddress));
+}
+
+/**
+ * mpi3mr_get_chain_idx - get free chain buffer index
+ * @mrioc: Adapter instance reference
+ *
+ * Try to get a free chain buffer index from the free pool.
+ *
+ * Return: -1 on failure or the free chain buffer index
+ */
+static int mpi3mr_get_chain_idx(struct mpi3mr_ioc *mrioc)
+{
+	u8 retry_count = 5;
+	int cmd_idx = -1;
+
+	do {
+		spin_lock(&mrioc->chain_buf_lock);
+		cmd_idx = find_first_zero_bit(mrioc->chain_bitmap,
+		    mrioc->chain_buf_count);
+		if (cmd_idx < mrioc->chain_buf_count) {
+			set_bit(cmd_idx, mrioc->chain_bitmap);
+			spin_unlock(&mrioc->chain_buf_lock);
+			break;
+		}
+		spin_unlock(&mrioc->chain_buf_lock);
+		cmd_idx = -1;
+	} while (retry_count--);
+	return cmd_idx;
+}
+
+/**
+ * mpi3mr_prepare_sg_scmd - build scatter gather list
+ * @mrioc: Adapter instance reference
+ * @scmd: SCSI command reference
+ * @scsiio_req: MPI3 SCSI IO request
+ *
+ * This function maps SCSI command's data and protection SGEs to
+ * MPI request SGEs. If required additional 4K chain buffer is
+ * used to send the SGEs.
+ *
+ * Return: 0 on success, -ENOMEM on dma_map_sg failure
+ */
+static int mpi3mr_prepare_sg_scmd(struct mpi3mr_ioc *mrioc,
+	struct scsi_cmnd *scmd, Mpi3SCSIIORequest_t *scsiio_req)
+{
+	dma_addr_t chain_dma;
+	struct scatterlist *sg_scmd;
+	void *sg_local, *chain;
+	u32 chain_length;
+	int sges_left, chain_idx;
+	u32 sges_in_segment;
+	u8 simple_sgl_flags;
+	u8 simple_sgl_flags_last;
+	u8 last_chain_sgl_flags;
+	struct chain_element *chain_req;
+	struct scmd_priv *priv = NULL;
+
+	priv = scsi_cmd_priv(scmd);
+
+	simple_sgl_flags = MPI3_SGE_FLAGS_ELEMENT_TYPE_SIMPLE |
+	    MPI3_SGE_FLAGS_DLAS_SYSTEM;
+	simple_sgl_flags_last = simple_sgl_flags |
+	    MPI3_SGE_FLAGS_END_OF_LIST;
+	last_chain_sgl_flags = MPI3_SGE_FLAGS_ELEMENT_TYPE_LAST_CHAIN |
+	    MPI3_SGE_FLAGS_DLAS_SYSTEM;
+
+	sg_local = &scsiio_req->SGL;
+
+	if (!scsiio_req->DataLength) {
+		mpi3mr_build_zero_len_sge(sg_local);
+		return 0;
+	}
+
+	sg_scmd = scsi_sglist(scmd);
+	sges_left = scsi_dma_map(scmd);
+
+	if (sges_left < 0) {
+		sdev_printk(KERN_ERR, scmd->device,
+		    "scsi_dma_map failed: request for %d bytes!\n",
+		    scsi_bufflen(scmd));
+		return -ENOMEM;
+	}
+	if (sges_left > MPI3MR_SG_DEPTH) {
+		sdev_printk(KERN_ERR, scmd->device,
+		    "scsi_dma_map returned unsupported sge count %d!\n",
+		    sges_left);
+		return -ENOMEM;
+	}
+
+	sges_in_segment = (mrioc->facts.op_req_sz -
+	    offsetof(Mpi3SCSIIORequest_t, SGL))/sizeof(Mpi3SGESimple_t);
+
+	if (sges_left <= sges_in_segment)
+		goto fill_in_last_segment;
+
+	/* fill in main message segment when there is a chain following */
+	while (sges_in_segment > 1) {
+		mpi3mr_add_sg_single(sg_local, simple_sgl_flags,
+		    sg_dma_len(sg_scmd), sg_dma_address(sg_scmd));
+		sg_scmd = sg_next(sg_scmd);
+		sg_local += sizeof(Mpi3SGESimple_t);
+		sges_left--;
+		sges_in_segment--;
+	}
+
+	chain_idx = mpi3mr_get_chain_idx(mrioc);
+	if (chain_idx < 0)
+		return -1;
+	chain_req = &mrioc->chain_sgl_list[chain_idx];
+	priv->chain_idx = chain_idx;
+
+	chain = chain_req->addr;
+	chain_dma = chain_req->dma_addr;
+	sges_in_segment = sges_left;
+	chain_length = sges_in_segment * sizeof(Mpi3SGESimple_t);
+
+	mpi3mr_add_sg_single(sg_local, last_chain_sgl_flags,
+	    chain_length, chain_dma);
+
+	sg_local = chain;
+
+fill_in_last_segment:
+	while (sges_left > 0) {
+		if (sges_left == 1)
+			mpi3mr_add_sg_single(sg_local,
+			    simple_sgl_flags_last, sg_dma_len(sg_scmd),
+			    sg_dma_address(sg_scmd));
+		else
+			mpi3mr_add_sg_single(sg_local, simple_sgl_flags,
+			    sg_dma_len(sg_scmd), sg_dma_address(sg_scmd));
+		sg_scmd = sg_next(sg_scmd);
+		sg_local += sizeof(Mpi3SGESimple_t);
+		sges_left--;
+	}
+
+	return 0;
+}
+
+/**
+ * mpi3mr_build_sg_scmd - build scatter gather list for SCSI IO
+ * @mrioc: Adapter instance reference
+ * @scmd: SCSI command reference
+ * @scsiio_req: MPI3 SCSI IO request
+ *
+ * This function calls mpi3mr_prepare_sg_scmd for constructing
+ * both data SGEs and protection information SGEs in the MPI
+ * format from the SCSI Command as appropriate .
+ *
+ * Return: return value of mpi3mr_prepare_sg_scmd.
+ */
+static int mpi3mr_build_sg_scmd(struct mpi3mr_ioc *mrioc,
+	struct scsi_cmnd *scmd, Mpi3SCSIIORequest_t *scsiio_req)
+{
+	int ret;
+
+	ret = mpi3mr_prepare_sg_scmd(mrioc, scmd, scsiio_req);
+	if (ret)
+		return ret;
+
+	return ret;
+}
+
 
 /**
  * mpi3mr_map_queues - Map queues callback handler
@@ -44,6 +509,73 @@  static int mpi3mr_map_queues(struct Scsi_Host *shost)
 	    mrioc->pdev, mrioc->op_reply_q_offset);
 }
 
+/**
+ * mpi3mr_scan_start - Scan start callback handler
+ * @shost: SCSI host reference
+ *
+ * Issue port enable request asynchronously.
+ *
+ * Return: Nothing
+ */
+static void mpi3mr_scan_start(struct Scsi_Host *shost)
+{
+	struct mpi3mr_ioc *mrioc = shost_priv(shost);
+
+	mrioc->scan_started = 1;
+	ioc_info(mrioc, "%s :Issuing Port Enable\n", __func__);
+	if (mpi3mr_issue_port_enable(mrioc, 1)) {
+		ioc_err(mrioc, "%s :Issuing port enable failed\n", __func__);
+		mrioc->scan_started = 0;
+		mrioc->scan_failed = MPI3_IOCSTATUS_INTERNAL_ERROR;
+	}
+
+}
+
+/**
+ * mpi3mr_scan_finished - Scan finished callback handler
+ * @shost: SCSI host reference
+ * @time: Jiffies from the scan start
+ *
+ * Checks whether the port enable is completed or timedout or
+ * failed and set the scan status accordingly after taking any
+ * recovery if required.
+ *
+ * Return: 1 on scan finished or timed out, 0 for in progress
+ */
+static int mpi3mr_scan_finished(struct Scsi_Host *shost,
+	unsigned long time)
+{
+	struct mpi3mr_ioc *mrioc = shost_priv(shost);
+	u32 pe_timeout = MPI3MR_PORTENABLE_TIMEOUT;
+
+	if (time >= (pe_timeout * HZ)) {
+		mrioc->init_cmds.is_waiting = 0;
+		mrioc->init_cmds.callback = NULL;
+		mrioc->init_cmds.state = MPI3MR_CMD_NOTUSED;
+		ioc_err(mrioc, "%s :port enable request timed out\n", __func__);
+		mrioc->is_driver_loading = 0;
+		mpi3mr_soft_reset_handler(mrioc,
+		    MPI3MR_RESET_FROM_PE_TIMEOUT, 1);
+	}
+
+	if (mrioc->scan_failed) {
+		ioc_err(mrioc,
+		    "%s :port enable failed with (ioc_status=0x%08x)\n",
+		    __func__, mrioc->scan_failed);
+		mrioc->is_driver_loading = 0;
+		mrioc->stop_drv_processing = 1;
+		return 1;
+	}
+
+	if (mrioc->scan_started)
+		return 0;
+	ioc_info(mrioc, "%s :port enable: SUCCESS\n", __func__);
+	mrioc->is_driver_loading = 0;
+
+	return 1;
+}
+
+
 /**
  * mpi3mr_slave_destroy - Slave destroy callback handler
  * @sdev: SCSI device reference
@@ -126,10 +658,114 @@  static int mpi3mr_target_alloc(struct scsi_target *starget)
 static int mpi3mr_qcmd(struct Scsi_Host *shost,
 	struct scsi_cmnd *scmd)
 {
+	struct mpi3mr_ioc *mrioc = shost_priv(shost);
+	struct mpi3mr_stgt_priv_data *stgt_priv_data;
+	struct mpi3mr_sdev_priv_data *sdev_priv_data;
+	struct scmd_priv *scmd_priv_data = NULL;
+	Mpi3SCSIIORequest_t *scsiio_req = NULL;
+	struct op_req_qinfo *op_req_q = NULL;
 	int retval = 0;
+	u16 dev_handle;
+	u16 host_tag;
+	u32 scsiio_flags = 0;
+	struct request *rq = scmd->request;
+	int iprio_class;
+
+	sdev_priv_data = scmd->device->hostdata;
+	if (!sdev_priv_data || !sdev_priv_data->tgt_priv_data) {
+		scmd->result = DID_NO_CONNECT << 16;
+		scmd->scsi_done(scmd);
+		goto out;
+	}
 
-	scmd->result = DID_NO_CONNECT << 16;
-	scmd->scsi_done(scmd);
+	if (mrioc->stop_drv_processing) {
+		scmd->result = DID_NO_CONNECT << 16;
+		scmd->scsi_done(scmd);
+		goto out;
+	}
+
+	if (mrioc->reset_in_progress) {
+		retval = SCSI_MLQUEUE_HOST_BUSY;
+		goto out;
+	}
+
+	stgt_priv_data = sdev_priv_data->tgt_priv_data;
+
+	dev_handle = stgt_priv_data->dev_handle;
+	if (dev_handle == MPI3MR_INVALID_DEV_HANDLE) {
+		scmd->result = DID_NO_CONNECT << 16;
+		scmd->scsi_done(scmd);
+		goto out;
+	}
+	if (stgt_priv_data->dev_removed) {
+		scmd->result = DID_NO_CONNECT << 16;
+		scmd->scsi_done(scmd);
+		goto out;
+	}
+
+	if (atomic_read(&stgt_priv_data->block_io)) {
+		if (mrioc->stop_drv_processing) {
+			scmd->result = DID_NO_CONNECT << 16;
+			scmd->scsi_done(scmd);
+			goto out;
+		}
+		retval = SCSI_MLQUEUE_DEVICE_BUSY;
+		goto out;
+	}
+
+	host_tag = mpi3mr_host_tag_for_scmd(mrioc, scmd);
+	if (host_tag == MPI3MR_HOSTTAG_INVALID) {
+		scmd->result = DID_ERROR << 16;
+		scmd->scsi_done(scmd);
+		goto out;
+	}
+
+	if (scmd->sc_data_direction == DMA_FROM_DEVICE)
+		scsiio_flags = MPI3_SCSIIO_FLAGS_DATADIRECTION_READ;
+	else if (scmd->sc_data_direction == DMA_TO_DEVICE)
+		scsiio_flags = MPI3_SCSIIO_FLAGS_DATADIRECTION_WRITE;
+	else
+		scsiio_flags = MPI3_SCSIIO_FLAGS_DATADIRECTION_NO_DATA_TRANSFER;
+
+	scsiio_flags |= MPI3_SCSIIO_FLAGS_TASKATTRIBUTE_SIMPLEQ;
+
+	if (sdev_priv_data->ncq_prio_enable) {
+		iprio_class = IOPRIO_PRIO_CLASS(req_get_ioprio(rq));
+		if (iprio_class == IOPRIO_CLASS_RT)
+			scsiio_flags |= 1 << MPI3_SCSIIO_FLAGS_CMDPRI_SHIFT;
+	}
+
+	if (scmd->cmd_len > 16)
+		scsiio_flags |= MPI3_SCSIIO_FLAGS_CDB_GREATER_THAN_16;
+
+	scmd_priv_data = scsi_cmd_priv(scmd);
+	memset(scmd_priv_data->mpi3mr_scsiio_req, 0, MPI3MR_ADMIN_REQ_FRAME_SZ);
+	scsiio_req = (Mpi3SCSIIORequest_t *) scmd_priv_data->mpi3mr_scsiio_req;
+	scsiio_req->Function = MPI3_FUNCTION_SCSI_IO;
+	scsiio_req->HostTag = cpu_to_le16(host_tag);
+
+	memcpy(scsiio_req->CDB.CDB32, scmd->cmnd, scmd->cmd_len);
+	scsiio_req->DataLength = cpu_to_le32(scsi_bufflen(scmd));
+	scsiio_req->DevHandle = cpu_to_le16(dev_handle);
+	scsiio_req->Flags = cpu_to_le32(scsiio_flags);
+	int_to_scsilun(sdev_priv_data->lun_id,
+	    (struct scsi_lun *)scsiio_req->LUN);
+
+	if (mpi3mr_build_sg_scmd(mrioc, scmd, scsiio_req)) {
+		mpi3mr_clear_scmd_priv(mrioc, scmd);
+		retval = SCSI_MLQUEUE_HOST_BUSY;
+		goto out;
+	}
+	op_req_q = &mrioc->req_qinfo[scmd_priv_data->req_q_idx];
+
+	if (mpi3mr_op_request_post(mrioc, op_req_q,
+	    scmd_priv_data->mpi3mr_scsiio_req)) {
+		mpi3mr_clear_scmd_priv(mrioc, scmd);
+		retval = SCSI_MLQUEUE_HOST_BUSY;
+		goto out;
+	}
+
+out:
 	return retval;
 }
 
@@ -143,6 +779,8 @@  static struct scsi_host_template mpi3mr_driver_template = {
 	.slave_configure		= mpi3mr_slave_configure,
 	.target_destroy			= mpi3mr_target_destroy,
 	.slave_destroy			= mpi3mr_slave_destroy,
+	.scan_finished			= mpi3mr_scan_finished,
+	.scan_start			= mpi3mr_scan_start,
 	.map_queues			= mpi3mr_map_queues,
 	.no_write_same			= 1,
 	.can_queue			= 1,
@@ -218,6 +856,7 @@  mpi3mr_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	spin_lock_init(&mrioc->admin_req_lock);
 	spin_lock_init(&mrioc->reply_free_queue_lock);
 	spin_lock_init(&mrioc->sbq_lock);
+	spin_lock_init(&mrioc->chain_buf_lock);
 
 	mpi3mr_init_drv_cmd(&mrioc->init_cmds, MPI3MR_HOSTTAG_INITCMDS);
 	if (pdev->revision)
@@ -287,6 +926,7 @@  static void mpi3mr_remove(struct pci_dev *pdev)
 	while (mrioc->reset_in_progress || mrioc->is_driver_loading)
 		ssleep(1);
 
+	mrioc->stop_drv_processing = 1;
 
 	scsi_remove_host(shost);
 
@@ -319,6 +959,7 @@  static void mpi3mr_shutdown(struct pci_dev *pdev)
 	mrioc = shost_priv(shost);
 	while (mrioc->reset_in_progress || mrioc->is_driver_loading)
 		ssleep(1);
+	mrioc->stop_drv_processing = 1;
 
 	mpi3mr_cleanup_ioc(mrioc);