]> git.karo-electronics.de Git - karo-tx-linux.git/blobdiff - drivers/scsi/lpfc/lpfc_scsi.c
[SCSI] lpfc 8.3.0 : Fix system crash due to uninitialized node access
[karo-tx-linux.git] / drivers / scsi / lpfc / lpfc_scsi.c
index 1bcebbd3dfacf8a3588abbeece892e19f44eadd3..cf6b2d40a923e9a8c686085a58eefd3c68e12140 100644 (file)
@@ -32,6 +32,7 @@
 #include "lpfc_version.h"
 #include "lpfc_hw.h"
 #include "lpfc_sli.h"
+#include "lpfc_nl.h"
 #include "lpfc_disc.h"
 #include "lpfc_scsi.h"
 #include "lpfc.h"
 #define LPFC_RESET_WAIT  2
 #define LPFC_ABORT_WAIT  2
 
-/*
- * This function is called with no lock held when there is a resource
- * error in driver or in firmware.
- */
+/**
+ * lpfc_update_stats: Update statistical data for the command completion.
+ * @phba: Pointer to HBA object.
+ * @lpfc_cmd: lpfc scsi command object pointer.
+ *
+ * This function is called when there is a command completion and this
+ * function updates the statistical data for the command completion.
+ **/
+static void
+lpfc_update_stats(struct lpfc_hba *phba, struct  lpfc_scsi_buf *lpfc_cmd)
+{
+       struct lpfc_rport_data *rdata = lpfc_cmd->rdata;
+       struct lpfc_nodelist *pnode = rdata->pnode;
+       struct scsi_cmnd *cmd = lpfc_cmd->pCmd;
+       unsigned long flags;
+       struct Scsi_Host  *shost = cmd->device->host;
+       struct lpfc_vport *vport = (struct lpfc_vport *) shost->hostdata;
+       unsigned long latency;
+       int i;
+
+       if (cmd->result)
+               return;
+
+       spin_lock_irqsave(shost->host_lock, flags);
+       if (!vport->stat_data_enabled ||
+               vport->stat_data_blocked ||
+               !pnode->lat_data ||
+               (phba->bucket_type == LPFC_NO_BUCKET)) {
+               spin_unlock_irqrestore(shost->host_lock, flags);
+               return;
+       }
+       latency = jiffies_to_msecs(jiffies - lpfc_cmd->start_time);
+
+       if (phba->bucket_type == LPFC_LINEAR_BUCKET) {
+               i = (latency + phba->bucket_step - 1 - phba->bucket_base)/
+                       phba->bucket_step;
+               if (i >= LPFC_MAX_BUCKET_COUNT)
+                       i = LPFC_MAX_BUCKET_COUNT;
+       } else {
+               for (i = 0; i < LPFC_MAX_BUCKET_COUNT-1; i++)
+                       if (latency <= (phba->bucket_base +
+                               ((1<<i)*phba->bucket_step)))
+                               break;
+       }
+
+       pnode->lat_data[i].cmd_count++;
+       spin_unlock_irqrestore(shost->host_lock, flags);
+}
+
+/**
+ * lpfc_send_sdev_queuedepth_change_event: Posts a queuedepth change
+ *                   event.
+ * @phba: Pointer to HBA context object.
+ * @vport: Pointer to vport object.
+ * @ndlp: Pointer to FC node associated with the target.
+ * @lun: Lun number of the scsi device.
+ * @old_val: Old value of the queue depth.
+ * @new_val: New value of the queue depth.
+ *
+ * This function sends an event to the mgmt application indicating
+ * there is a change in the scsi device queue depth.
+ **/
+static void
+lpfc_send_sdev_queuedepth_change_event(struct lpfc_hba *phba,
+               struct lpfc_vport  *vport,
+               struct lpfc_nodelist *ndlp,
+               uint32_t lun,
+               uint32_t old_val,
+               uint32_t new_val)
+{
+       struct lpfc_fast_path_event *fast_path_evt;
+       unsigned long flags;
+
+       fast_path_evt = lpfc_alloc_fast_evt(phba);
+       if (!fast_path_evt)
+               return;
+
+       fast_path_evt->un.queue_depth_evt.scsi_event.event_type =
+               FC_REG_SCSI_EVENT;
+       fast_path_evt->un.queue_depth_evt.scsi_event.subcategory =
+               LPFC_EVENT_VARQUEDEPTH;
+
+       /* Report all luns with change in queue depth */
+       fast_path_evt->un.queue_depth_evt.scsi_event.lun = lun;
+       if (ndlp && NLP_CHK_NODE_ACT(ndlp)) {
+               memcpy(&fast_path_evt->un.queue_depth_evt.scsi_event.wwpn,
+                       &ndlp->nlp_portname, sizeof(struct lpfc_name));
+               memcpy(&fast_path_evt->un.queue_depth_evt.scsi_event.wwnn,
+                       &ndlp->nlp_nodename, sizeof(struct lpfc_name));
+       }
+
+       fast_path_evt->un.queue_depth_evt.oldval = old_val;
+       fast_path_evt->un.queue_depth_evt.newval = new_val;
+       fast_path_evt->vport = vport;
+
+       fast_path_evt->work_evt.evt = LPFC_EVT_FASTPATH_MGMT_EVT;
+       spin_lock_irqsave(&phba->hbalock, flags);
+       list_add_tail(&fast_path_evt->work_evt.evt_listp, &phba->work_list);
+       spin_unlock_irqrestore(&phba->hbalock, flags);
+       lpfc_worker_wake_up(phba);
+
+       return;
+}
+
+/**
+ * lpfc_adjust_queue_depth: Post RAMP_DOWN_QUEUE event for worker thread.
+ * @phba: The Hba for which this call is being executed.
+ *
+ * This routine is called when there is resource error in driver or firmware.
+ * This routine posts WORKER_RAMP_DOWN_QUEUE event for @phba. This routine
+ * posts at most 1 event each second. This routine wakes up worker thread of
+ * @phba to process WORKER_RAM_DOWN_EVENT event.
+ *
+ * This routine should be called with no lock held.
+ **/
 void
 lpfc_adjust_queue_depth(struct lpfc_hba *phba)
 {
@@ -76,10 +188,17 @@ lpfc_adjust_queue_depth(struct lpfc_hba *phba)
        return;
 }
 
-/*
- * This function is called with no lock held when there is a successful
- * SCSI command completion.
- */
+/**
+ * lpfc_rampup_queue_depth: Post RAMP_UP_QUEUE event for worker thread.
+ * @phba: The Hba for which this call is being executed.
+ *
+ * This routine post WORKER_RAMP_UP_QUEUE event for @phba vport. This routine
+ * post at most 1 event every 5 minute after last_ramp_up_time or
+ * last_rsrc_error_time.  This routine wakes up worker thread of @phba
+ * to process WORKER_RAM_DOWN_EVENT event.
+ *
+ * This routine should be called with no lock held.
+ **/
 static inline void
 lpfc_rampup_queue_depth(struct lpfc_vport  *vport,
                        struct scsi_device *sdev)
@@ -111,15 +230,24 @@ lpfc_rampup_queue_depth(struct lpfc_vport  *vport,
        return;
 }
 
+/**
+ * lpfc_ramp_down_queue_handler: WORKER_RAMP_DOWN_QUEUE event handler.
+ * @phba: The Hba for which this call is being executed.
+ *
+ * This routine is called to  process WORKER_RAMP_DOWN_QUEUE event for worker
+ * thread.This routine reduces queue depth for all scsi device on each vport
+ * associated with @phba.
+ **/
 void
 lpfc_ramp_down_queue_handler(struct lpfc_hba *phba)
 {
        struct lpfc_vport **vports;
        struct Scsi_Host  *shost;
        struct scsi_device *sdev;
-       unsigned long new_queue_depth;
+       unsigned long new_queue_depth, old_queue_depth;
        unsigned long num_rsrc_err, num_cmd_success;
        int i;
+       struct lpfc_rport_data *rdata;
 
        num_rsrc_err = atomic_read(&phba->num_rsrc_err);
        num_cmd_success = atomic_read(&phba->num_cmd_success);
@@ -137,6 +265,7 @@ lpfc_ramp_down_queue_handler(struct lpfc_hba *phba)
                                else
                                        new_queue_depth = sdev->queue_depth -
                                                                new_queue_depth;
+                               old_queue_depth = sdev->queue_depth;
                                if (sdev->ordered_tags)
                                        scsi_adjust_queue_depth(sdev,
                                                        MSG_ORDERED_TAG,
@@ -145,6 +274,13 @@ lpfc_ramp_down_queue_handler(struct lpfc_hba *phba)
                                        scsi_adjust_queue_depth(sdev,
                                                        MSG_SIMPLE_TAG,
                                                        new_queue_depth);
+                               rdata = sdev->hostdata;
+                               if (rdata)
+                                       lpfc_send_sdev_queuedepth_change_event(
+                                               phba, vports[i],
+                                               rdata->pnode,
+                                               sdev->lun, old_queue_depth,
+                                               new_queue_depth);
                        }
                }
        lpfc_destroy_vport_work_array(phba, vports);
@@ -152,6 +288,15 @@ lpfc_ramp_down_queue_handler(struct lpfc_hba *phba)
        atomic_set(&phba->num_cmd_success, 0);
 }
 
+/**
+ * lpfc_ramp_up_queue_handler: WORKER_RAMP_UP_QUEUE event handler.
+ * @phba: The Hba for which this call is being executed.
+ *
+ * This routine is called to  process WORKER_RAMP_UP_QUEUE event for worker
+ * thread.This routine increases queue depth for all scsi device on each vport
+ * associated with @phba by 1. This routine also sets @phba num_rsrc_err and
+ * num_cmd_success to zero.
+ **/
 void
 lpfc_ramp_up_queue_handler(struct lpfc_hba *phba)
 {
@@ -159,6 +304,7 @@ lpfc_ramp_up_queue_handler(struct lpfc_hba *phba)
        struct Scsi_Host  *shost;
        struct scsi_device *sdev;
        int i;
+       struct lpfc_rport_data *rdata;
 
        vports = lpfc_create_vport_work_array(phba);
        if (vports != NULL)
@@ -176,6 +322,14 @@ lpfc_ramp_up_queue_handler(struct lpfc_hba *phba)
                                        scsi_adjust_queue_depth(sdev,
                                                        MSG_SIMPLE_TAG,
                                                        sdev->queue_depth+1);
+                               rdata = sdev->hostdata;
+                               if (rdata)
+                                       lpfc_send_sdev_queuedepth_change_event(
+                                               phba, vports[i],
+                                               rdata->pnode,
+                                               sdev->lun,
+                                               sdev->queue_depth - 1,
+                                               sdev->queue_depth);
                        }
                }
        lpfc_destroy_vport_work_array(phba, vports);
@@ -183,14 +337,50 @@ lpfc_ramp_up_queue_handler(struct lpfc_hba *phba)
        atomic_set(&phba->num_cmd_success, 0);
 }
 
-/*
+/**
+ * lpfc_scsi_dev_block: set all scsi hosts to block state.
+ * @phba: Pointer to HBA context object.
+ *
+ * This function walks vport list and set each SCSI host to block state
+ * by invoking fc_remote_port_delete() routine. This function is invoked
+ * with EEH when device's PCI slot has been permanently disabled.
+ **/
+void
+lpfc_scsi_dev_block(struct lpfc_hba *phba)
+{
+       struct lpfc_vport **vports;
+       struct Scsi_Host  *shost;
+       struct scsi_device *sdev;
+       struct fc_rport *rport;
+       int i;
+
+       vports = lpfc_create_vport_work_array(phba);
+       if (vports != NULL)
+               for (i = 0; i <= phba->max_vpi && vports[i] != NULL; i++) {
+                       shost = lpfc_shost_from_vport(vports[i]);
+                       shost_for_each_device(sdev, shost) {
+                               rport = starget_to_rport(scsi_target(sdev));
+                               fc_remote_port_delete(rport);
+                       }
+               }
+       lpfc_destroy_vport_work_array(phba, vports);
+}
+
+/**
+ * lpfc_new_scsi_buf: Scsi buffer allocator.
+ * @vport: The virtual port for which this call being executed.
+ *
  * This routine allocates a scsi buffer, which contains all the necessary
  * information needed to initiate a SCSI I/O.  The non-DMAable buffer region
  * contains information to build the IOCB.  The DMAable region contains
- * memory for the FCP CMND, FCP RSP, and the inital BPL.  In addition to
- * allocating memeory, the FCP CMND and FCP RSP BDEs are setup in the BPL
+ * memory for the FCP CMND, FCP RSP, and the initial BPL.  In addition to
+ * allocating memory, the FCP CMND and FCP RSP BDEs are setup in the BPL
  * and the BPL BDE is setup in the IOCB.
- */
+ *
+ * Return codes:
+ *   NULL - Error
+ *   Pointer to lpfc_scsi_buf data structure - Success
+ **/
 static struct lpfc_scsi_buf *
 lpfc_new_scsi_buf(struct lpfc_vport *vport)
 {
@@ -198,7 +388,9 @@ lpfc_new_scsi_buf(struct lpfc_vport *vport)
        struct lpfc_scsi_buf *psb;
        struct ulp_bde64 *bpl;
        IOCB_t *iocb;
-       dma_addr_t pdma_phys;
+       dma_addr_t pdma_phys_fcp_cmd;
+       dma_addr_t pdma_phys_fcp_rsp;
+       dma_addr_t pdma_phys_bpl;
        uint16_t iotag;
 
        psb = kzalloc(sizeof(struct lpfc_scsi_buf), GFP_KERNEL);
@@ -238,45 +430,76 @@ lpfc_new_scsi_buf(struct lpfc_vport *vport)
 
        /* Initialize local short-hand pointers. */
        bpl = psb->fcp_bpl;
-       pdma_phys = psb->dma_handle;
+       pdma_phys_fcp_cmd = psb->dma_handle;
+       pdma_phys_fcp_rsp = psb->dma_handle + sizeof(struct fcp_cmnd);
+       pdma_phys_bpl = psb->dma_handle + sizeof(struct fcp_cmnd) +
+                       sizeof(struct fcp_rsp);
 
        /*
         * The first two bdes are the FCP_CMD and FCP_RSP.  The balance are sg
         * list bdes.  Initialize the first two and leave the rest for
         * queuecommand.
         */
-       bpl->addrHigh = le32_to_cpu(putPaddrHigh(pdma_phys));
-       bpl->addrLow = le32_to_cpu(putPaddrLow(pdma_phys));
-       bpl->tus.f.bdeSize = sizeof (struct fcp_cmnd);
-       bpl->tus.f.bdeFlags = BUFF_USE_CMND;
-       bpl->tus.w = le32_to_cpu(bpl->tus.w);
-       bpl++;
+       bpl[0].addrHigh = le32_to_cpu(putPaddrHigh(pdma_phys_fcp_cmd));
+       bpl[0].addrLow = le32_to_cpu(putPaddrLow(pdma_phys_fcp_cmd));
+       bpl[0].tus.f.bdeSize = sizeof(struct fcp_cmnd);
+       bpl[0].tus.f.bdeFlags = BUFF_TYPE_BDE_64;
+       bpl[0].tus.w = le32_to_cpu(bpl->tus.w);
 
        /* Setup the physical region for the FCP RSP */
-       pdma_phys += sizeof (struct fcp_cmnd);
-       bpl->addrHigh = le32_to_cpu(putPaddrHigh(pdma_phys));
-       bpl->addrLow = le32_to_cpu(putPaddrLow(pdma_phys));
-       bpl->tus.f.bdeSize = sizeof (struct fcp_rsp);
-       bpl->tus.f.bdeFlags = (BUFF_USE_CMND | BUFF_USE_RCV);
-       bpl->tus.w = le32_to_cpu(bpl->tus.w);
+       bpl[1].addrHigh = le32_to_cpu(putPaddrHigh(pdma_phys_fcp_rsp));
+       bpl[1].addrLow = le32_to_cpu(putPaddrLow(pdma_phys_fcp_rsp));
+       bpl[1].tus.f.bdeSize = sizeof(struct fcp_rsp);
+       bpl[1].tus.f.bdeFlags = BUFF_TYPE_BDE_64;
+       bpl[1].tus.w = le32_to_cpu(bpl->tus.w);
 
        /*
         * Since the IOCB for the FCP I/O is built into this lpfc_scsi_buf,
         * initialize it with all known data now.
         */
-       pdma_phys += (sizeof (struct fcp_rsp));
        iocb = &psb->cur_iocbq.iocb;
        iocb->un.fcpi64.bdl.ulpIoTag32 = 0;
-       iocb->un.fcpi64.bdl.addrHigh = putPaddrHigh(pdma_phys);
-       iocb->un.fcpi64.bdl.addrLow = putPaddrLow(pdma_phys);
-       iocb->un.fcpi64.bdl.bdeSize = (2 * sizeof (struct ulp_bde64));
-       iocb->un.fcpi64.bdl.bdeFlags = BUFF_TYPE_BDL;
-       iocb->ulpBdeCount = 1;
+       if (phba->sli_rev == 3) {
+               /* fill in immediate fcp command BDE */
+               iocb->un.fcpi64.bdl.bdeFlags = BUFF_TYPE_BDE_IMMED;
+               iocb->un.fcpi64.bdl.bdeSize = sizeof(struct fcp_cmnd);
+               iocb->un.fcpi64.bdl.addrLow = offsetof(IOCB_t,
+                                                      unsli3.fcp_ext.icd);
+               iocb->un.fcpi64.bdl.addrHigh = 0;
+               iocb->ulpBdeCount = 0;
+               iocb->ulpLe = 0;
+               /* fill in responce BDE */
+               iocb->unsli3.fcp_ext.rbde.tus.f.bdeFlags = BUFF_TYPE_BDE_64;
+               iocb->unsli3.fcp_ext.rbde.tus.f.bdeSize =
+                                               sizeof(struct fcp_rsp);
+               iocb->unsli3.fcp_ext.rbde.addrLow =
+                                               putPaddrLow(pdma_phys_fcp_rsp);
+               iocb->unsli3.fcp_ext.rbde.addrHigh =
+                                               putPaddrHigh(pdma_phys_fcp_rsp);
+       } else {
+               iocb->un.fcpi64.bdl.bdeFlags = BUFF_TYPE_BLP_64;
+               iocb->un.fcpi64.bdl.bdeSize = (2 * sizeof(struct ulp_bde64));
+               iocb->un.fcpi64.bdl.addrLow = putPaddrLow(pdma_phys_bpl);
+               iocb->un.fcpi64.bdl.addrHigh = putPaddrHigh(pdma_phys_bpl);
+               iocb->ulpBdeCount = 1;
+               iocb->ulpLe = 1;
+       }
        iocb->ulpClass = CLASS3;
 
        return psb;
 }
 
+/**
+ * lpfc_get_scsi_buf: Get a scsi buffer from lpfc_scsi_buf_list list of Hba.
+ * @phba: The Hba for which this call is being executed.
+ *
+ * This routine removes a scsi buffer from head of @phba lpfc_scsi_buf_list list
+ * and returns to caller.
+ *
+ * Return codes:
+ *   NULL - Error
+ *   Pointer to lpfc_scsi_buf - Success
+ **/
 static struct lpfc_scsi_buf*
 lpfc_get_scsi_buf(struct lpfc_hba * phba)
 {
@@ -294,6 +517,14 @@ lpfc_get_scsi_buf(struct lpfc_hba * phba)
        return  lpfc_cmd;
 }
 
+/**
+ * lpfc_release_scsi_buf: Return a scsi buffer back to hba lpfc_scsi_buf_list list.
+ * @phba: The Hba for which this call is being executed.
+ * @psb: The scsi buffer which is being released.
+ *
+ * This routine releases @psb scsi buffer by adding it to tail of @phba
+ * lpfc_scsi_buf_list list.
+ **/
 static void
 lpfc_release_scsi_buf(struct lpfc_hba *phba, struct lpfc_scsi_buf *psb)
 {
@@ -305,6 +536,20 @@ lpfc_release_scsi_buf(struct lpfc_hba *phba, struct lpfc_scsi_buf *psb)
        spin_unlock_irqrestore(&phba->scsi_buf_list_lock, iflag);
 }
 
+/**
+ * lpfc_scsi_prep_dma_buf: Routine to do DMA mapping for scsi buffer.
+ * @phba: The Hba for which this call is being executed.
+ * @lpfc_cmd: The scsi buffer which is going to be mapped.
+ *
+ * This routine does the pci dma mapping for scatter-gather list of scsi cmnd
+ * field of @lpfc_cmd. This routine scans through sg elements and format the
+ * bdea. This routine also initializes all IOCB fields which are dependent on
+ * scsi command request buffer.
+ *
+ * Return codes:
+ *   1 - Error
+ *   0 - Success
+ **/
 static int
 lpfc_scsi_prep_dma_buf(struct lpfc_hba *phba, struct lpfc_scsi_buf *lpfc_cmd)
 {
@@ -313,8 +558,9 @@ lpfc_scsi_prep_dma_buf(struct lpfc_hba *phba, struct lpfc_scsi_buf *lpfc_cmd)
        struct fcp_cmnd *fcp_cmnd = lpfc_cmd->fcp_cmnd;
        struct ulp_bde64 *bpl = lpfc_cmd->fcp_bpl;
        IOCB_t *iocb_cmd = &lpfc_cmd->cur_iocbq.iocb;
+       struct ulp_bde64 *data_bde = iocb_cmd->unsli3.fcp_ext.dbde;
        dma_addr_t physaddr;
-       uint32_t i, num_bde = 0;
+       uint32_t num_bde = 0;
        int nseg, datadir = scsi_cmnd->sc_data_direction;
 
        /*
@@ -352,37 +598,168 @@ lpfc_scsi_prep_dma_buf(struct lpfc_hba *phba, struct lpfc_scsi_buf *lpfc_cmd)
                 * during probe that limits the number of sg elements in any
                 * single scsi command.  Just run through the seg_cnt and format
                 * the bde's.
+                * When using SLI-3 the driver will try to fit all the BDEs into
+                * the IOCB. If it can't then the BDEs get added to a BPL as it
+                * does for SLI-2 mode.
                 */
-               scsi_for_each_sg(scsi_cmnd, sgel, nseg, i) {
+               scsi_for_each_sg(scsi_cmnd, sgel, nseg, num_bde) {
                        physaddr = sg_dma_address(sgel);
-                       bpl->addrLow = le32_to_cpu(putPaddrLow(physaddr));
-                       bpl->addrHigh = le32_to_cpu(putPaddrHigh(physaddr));
-                       bpl->tus.f.bdeSize = sg_dma_len(sgel);
-                       if (datadir == DMA_TO_DEVICE)
-                               bpl->tus.f.bdeFlags = 0;
-                       else
-                               bpl->tus.f.bdeFlags = BUFF_USE_RCV;
-                       bpl->tus.w = le32_to_cpu(bpl->tus.w);
-                       bpl++;
-                       num_bde++;
+                       if (phba->sli_rev == 3 &&
+                           nseg <= LPFC_EXT_DATA_BDE_COUNT) {
+                               data_bde->tus.f.bdeFlags = BUFF_TYPE_BDE_64;
+                               data_bde->tus.f.bdeSize = sg_dma_len(sgel);
+                               data_bde->addrLow = putPaddrLow(physaddr);
+                               data_bde->addrHigh = putPaddrHigh(physaddr);
+                               data_bde++;
+                       } else {
+                               bpl->tus.f.bdeFlags = BUFF_TYPE_BDE_64;
+                               bpl->tus.f.bdeSize = sg_dma_len(sgel);
+                               bpl->tus.w = le32_to_cpu(bpl->tus.w);
+                               bpl->addrLow =
+                                       le32_to_cpu(putPaddrLow(physaddr));
+                               bpl->addrHigh =
+                                       le32_to_cpu(putPaddrHigh(physaddr));
+                               bpl++;
+                       }
                }
        }
 
        /*
         * Finish initializing those IOCB fields that are dependent on the
-        * scsi_cmnd request_buffer.  Note that the bdeSize is explicitly
-        * reinitialized since all iocb memory resources are used many times
-        * for transmit, receive, and continuation bpl's.
+        * scsi_cmnd request_buffer.  Note that for SLI-2 the bdeSize is
+        * explicitly reinitialized and for SLI-3 the extended bde count is
+        * explicitly reinitialized since all iocb memory resources are reused.
         */
-       iocb_cmd->un.fcpi64.bdl.bdeSize = (2 * sizeof (struct ulp_bde64));
-       iocb_cmd->un.fcpi64.bdl.bdeSize +=
-               (num_bde * sizeof (struct ulp_bde64));
-       iocb_cmd->ulpBdeCount = 1;
-       iocb_cmd->ulpLe = 1;
+       if (phba->sli_rev == 3) {
+               if (num_bde > LPFC_EXT_DATA_BDE_COUNT) {
+                       /*
+                        * The extended IOCB format can only fit 3 BDE or a BPL.
+                        * This I/O has more than 3 BDE so the 1st data bde will
+                        * be a BPL that is filled in here.
+                        */
+                       physaddr = lpfc_cmd->dma_handle;
+                       data_bde->tus.f.bdeFlags = BUFF_TYPE_BLP_64;
+                       data_bde->tus.f.bdeSize = (num_bde *
+                                                  sizeof(struct ulp_bde64));
+                       physaddr += (sizeof(struct fcp_cmnd) +
+                                    sizeof(struct fcp_rsp) +
+                                    (2 * sizeof(struct ulp_bde64)));
+                       data_bde->addrHigh = putPaddrHigh(physaddr);
+                       data_bde->addrLow = putPaddrLow(physaddr);
+                       /* ebde count includes the responce bde and data bpl */
+                       iocb_cmd->unsli3.fcp_ext.ebde_count = 2;
+               } else {
+                       /* ebde count includes the responce bde and data bdes */
+                       iocb_cmd->unsli3.fcp_ext.ebde_count = (num_bde + 1);
+               }
+       } else {
+               iocb_cmd->un.fcpi64.bdl.bdeSize =
+                       ((num_bde + 2) * sizeof(struct ulp_bde64));
+       }
        fcp_cmnd->fcpDl = cpu_to_be32(scsi_bufflen(scsi_cmnd));
        return 0;
 }
 
+/**
+ * lpfc_send_scsi_error_event: Posts an event when there is SCSI error.
+ * @phba: Pointer to hba context object.
+ * @vport: Pointer to vport object.
+ * @lpfc_cmd: Pointer to lpfc scsi command which reported the error.
+ * @rsp_iocb: Pointer to response iocb object which reported error.
+ *
+ * This function posts an event when there is a SCSI command reporting
+ * error from the scsi device.
+ **/
+static void
+lpfc_send_scsi_error_event(struct lpfc_hba *phba, struct lpfc_vport *vport,
+               struct lpfc_scsi_buf *lpfc_cmd, struct lpfc_iocbq *rsp_iocb) {
+       struct scsi_cmnd *cmnd = lpfc_cmd->pCmd;
+       struct fcp_rsp *fcprsp = lpfc_cmd->fcp_rsp;
+       uint32_t resp_info = fcprsp->rspStatus2;
+       uint32_t scsi_status = fcprsp->rspStatus3;
+       uint32_t fcpi_parm = rsp_iocb->iocb.un.fcpi.fcpi_parm;
+       struct lpfc_fast_path_event *fast_path_evt = NULL;
+       struct lpfc_nodelist *pnode = lpfc_cmd->rdata->pnode;
+       unsigned long flags;
+
+       /* If there is queuefull or busy condition send a scsi event */
+       if ((cmnd->result == SAM_STAT_TASK_SET_FULL) ||
+               (cmnd->result == SAM_STAT_BUSY)) {
+               fast_path_evt = lpfc_alloc_fast_evt(phba);
+               if (!fast_path_evt)
+                       return;
+               fast_path_evt->un.scsi_evt.event_type =
+                       FC_REG_SCSI_EVENT;
+               fast_path_evt->un.scsi_evt.subcategory =
+               (cmnd->result == SAM_STAT_TASK_SET_FULL) ?
+               LPFC_EVENT_QFULL : LPFC_EVENT_DEVBSY;
+               fast_path_evt->un.scsi_evt.lun = cmnd->device->lun;
+               memcpy(&fast_path_evt->un.scsi_evt.wwpn,
+                       &pnode->nlp_portname, sizeof(struct lpfc_name));
+               memcpy(&fast_path_evt->un.scsi_evt.wwnn,
+                       &pnode->nlp_nodename, sizeof(struct lpfc_name));
+       } else if ((resp_info & SNS_LEN_VALID) && fcprsp->rspSnsLen &&
+               ((cmnd->cmnd[0] == READ_10) || (cmnd->cmnd[0] == WRITE_10))) {
+               fast_path_evt = lpfc_alloc_fast_evt(phba);
+               if (!fast_path_evt)
+                       return;
+               fast_path_evt->un.check_cond_evt.scsi_event.event_type =
+                       FC_REG_SCSI_EVENT;
+               fast_path_evt->un.check_cond_evt.scsi_event.subcategory =
+                       LPFC_EVENT_CHECK_COND;
+               fast_path_evt->un.check_cond_evt.scsi_event.lun =
+                       cmnd->device->lun;
+               memcpy(&fast_path_evt->un.check_cond_evt.scsi_event.wwpn,
+                       &pnode->nlp_portname, sizeof(struct lpfc_name));
+               memcpy(&fast_path_evt->un.check_cond_evt.scsi_event.wwnn,
+                       &pnode->nlp_nodename, sizeof(struct lpfc_name));
+               fast_path_evt->un.check_cond_evt.sense_key =
+                       cmnd->sense_buffer[2] & 0xf;
+               fast_path_evt->un.check_cond_evt.asc = cmnd->sense_buffer[12];
+               fast_path_evt->un.check_cond_evt.ascq = cmnd->sense_buffer[13];
+       } else if ((cmnd->sc_data_direction == DMA_FROM_DEVICE) &&
+                    fcpi_parm &&
+                    ((be32_to_cpu(fcprsp->rspResId) != fcpi_parm) ||
+                       ((scsi_status == SAM_STAT_GOOD) &&
+                       !(resp_info & (RESID_UNDER | RESID_OVER))))) {
+               /*
+                * If status is good or resid does not match with fcp_param and
+                * there is valid fcpi_parm, then there is a read_check error
+                */
+               fast_path_evt = lpfc_alloc_fast_evt(phba);
+               if (!fast_path_evt)
+                       return;
+               fast_path_evt->un.read_check_error.header.event_type =
+                       FC_REG_FABRIC_EVENT;
+               fast_path_evt->un.read_check_error.header.subcategory =
+                       LPFC_EVENT_FCPRDCHKERR;
+               memcpy(&fast_path_evt->un.read_check_error.header.wwpn,
+                       &pnode->nlp_portname, sizeof(struct lpfc_name));
+               memcpy(&fast_path_evt->un.read_check_error.header.wwnn,
+                       &pnode->nlp_nodename, sizeof(struct lpfc_name));
+               fast_path_evt->un.read_check_error.lun = cmnd->device->lun;
+               fast_path_evt->un.read_check_error.opcode = cmnd->cmnd[0];
+               fast_path_evt->un.read_check_error.fcpiparam =
+                       fcpi_parm;
+       } else
+               return;
+
+       fast_path_evt->vport = vport;
+       spin_lock_irqsave(&phba->hbalock, flags);
+       list_add_tail(&fast_path_evt->work_evt.evt_listp, &phba->work_list);
+       spin_unlock_irqrestore(&phba->hbalock, flags);
+       lpfc_worker_wake_up(phba);
+       return;
+}
+
+/**
+ * lpfc_scsi_unprep_dma_buf: Routine to un-map DMA mapping of scatter gather.
+ * @phba: The Hba for which this call is being executed.
+ * @psb: The scsi buffer which is going to be un-mapped.
+ *
+ * This routine does DMA un-mapping of scatter gather list of scsi command
+ * field of @lpfc_cmd.
+ **/
 static void
 lpfc_scsi_unprep_dma_buf(struct lpfc_hba * phba, struct lpfc_scsi_buf * psb)
 {
@@ -396,6 +773,16 @@ lpfc_scsi_unprep_dma_buf(struct lpfc_hba * phba, struct lpfc_scsi_buf * psb)
                scsi_dma_unmap(psb->pCmd);
 }
 
+/**
+ * lpfc_handler_fcp_err: FCP response handler.
+ * @vport: The virtual port for which this call is being executed.
+ * @lpfc_cmd: Pointer to lpfc_scsi_buf data structure.
+ * @rsp_iocb: The response IOCB which contains FCP error.
+ *
+ * This routine is called to process response IOCB with status field
+ * IOSTAT_FCP_RSP_ERROR. This routine sets result field of scsi command
+ * based upon SCSI and FCP error.
+ **/
 static void
 lpfc_handle_fcp_err(struct lpfc_vport *vport, struct lpfc_scsi_buf *lpfc_cmd,
                    struct lpfc_iocbq *rsp_iocb)
@@ -411,6 +798,7 @@ lpfc_handle_fcp_err(struct lpfc_vport *vport, struct lpfc_scsi_buf *lpfc_cmd,
        uint32_t rsplen = 0;
        uint32_t logit = LOG_FCP | LOG_FCP_ERROR;
 
+
        /*
         *  If this is a task management command, there is no
         *  scsi packet associated with this lpfc_cmd.  The driver
@@ -526,8 +914,19 @@ lpfc_handle_fcp_err(struct lpfc_vport *vport, struct lpfc_scsi_buf *lpfc_cmd,
 
  out:
        cmnd->result = ScsiResult(host_status, scsi_status);
+       lpfc_send_scsi_error_event(vport->phba, vport, lpfc_cmd, rsp_iocb);
 }
 
+/**
+ * lpfc_scsi_cmd_iocb_cmpl: Scsi cmnd IOCB completion routine.
+ * @phba: The Hba for which this call is being executed.
+ * @pIocbIn: The command IOCBQ for the scsi cmnd.
+ * @pIocbOut: The response IOCBQ for the scsi cmnd .
+ *
+ * This routine assigns scsi command result by looking into response IOCB
+ * status field appropriately. This routine handles QUEUE FULL condition as
+ * well by ramping down device queue depth.
+ **/
 static void
 lpfc_scsi_cmd_iocb_cmpl(struct lpfc_hba *phba, struct lpfc_iocbq *pIocbIn,
                        struct lpfc_iocbq *pIocbOut)
@@ -542,9 +941,12 @@ lpfc_scsi_cmd_iocb_cmpl(struct lpfc_hba *phba, struct lpfc_iocbq *pIocbIn,
        struct scsi_device *sdev, *tmp_sdev;
        int depth = 0;
        unsigned long flags;
+       struct lpfc_fast_path_event *fast_path_evt;
 
        lpfc_cmd->result = pIocbOut->iocb.un.ulpWord[4];
        lpfc_cmd->status = pIocbOut->iocb.ulpStatus;
+       if (pnode && NLP_CHK_NODE_ACT(pnode))
+               atomic_dec(&pnode->cmd_pending);
 
        if (lpfc_cmd->status) {
                if (lpfc_cmd->status == IOSTAT_LOCAL_REJECT &&
@@ -570,12 +972,36 @@ lpfc_scsi_cmd_iocb_cmpl(struct lpfc_hba *phba, struct lpfc_iocbq *pIocbIn,
                        break;
                case IOSTAT_NPORT_BSY:
                case IOSTAT_FABRIC_BSY:
-                       cmd->result = ScsiResult(DID_BUS_BUSY, 0);
+                       cmd->result = ScsiResult(DID_TRANSPORT_DISRUPTED, 0);
+                       fast_path_evt = lpfc_alloc_fast_evt(phba);
+                       if (!fast_path_evt)
+                               break;
+                       fast_path_evt->un.fabric_evt.event_type =
+                               FC_REG_FABRIC_EVENT;
+                       fast_path_evt->un.fabric_evt.subcategory =
+                               (lpfc_cmd->status == IOSTAT_NPORT_BSY) ?
+                               LPFC_EVENT_PORT_BUSY : LPFC_EVENT_FABRIC_BUSY;
+                       if (pnode && NLP_CHK_NODE_ACT(pnode)) {
+                               memcpy(&fast_path_evt->un.fabric_evt.wwpn,
+                                       &pnode->nlp_portname,
+                                       sizeof(struct lpfc_name));
+                               memcpy(&fast_path_evt->un.fabric_evt.wwnn,
+                                       &pnode->nlp_nodename,
+                                       sizeof(struct lpfc_name));
+                       }
+                       fast_path_evt->vport = vport;
+                       fast_path_evt->work_evt.evt =
+                               LPFC_EVT_FASTPATH_MGMT_EVT;
+                       spin_lock_irqsave(&phba->hbalock, flags);
+                       list_add_tail(&fast_path_evt->work_evt.evt_listp,
+                               &phba->work_list);
+                       spin_unlock_irqrestore(&phba->hbalock, flags);
+                       lpfc_worker_wake_up(phba);
                        break;
                case IOSTAT_LOCAL_REJECT:
-                       if (lpfc_cmd->result == RJT_UNAVAIL_PERM ||
+                       if (lpfc_cmd->result == IOERR_INVALID_RPI ||
                            lpfc_cmd->result == IOERR_NO_RESOURCES ||
-                           lpfc_cmd->result == RJT_LOGIN_REQUIRED) {
+                           lpfc_cmd->result == IOERR_ABORT_REQUESTED) {
                                cmd->result = ScsiResult(DID_REQUEUE, 0);
                                break;
                        } /* else: fall through */
@@ -586,7 +1012,8 @@ lpfc_scsi_cmd_iocb_cmpl(struct lpfc_hba *phba, struct lpfc_iocbq *pIocbIn,
 
                if (!pnode || !NLP_CHK_NODE_ACT(pnode)
                    || (pnode->nlp_state != NLP_STE_MAPPED_NODE))
-                       cmd->result = ScsiResult(DID_BUS_BUSY, SAM_STAT_BUSY);
+                       cmd->result = ScsiResult(DID_TRANSPORT_DISRUPTED,
+                                                SAM_STAT_BUSY);
        } else {
                cmd->result = ScsiResult(DID_OK, 0);
        }
@@ -602,8 +1029,40 @@ lpfc_scsi_cmd_iocb_cmpl(struct lpfc_hba *phba, struct lpfc_iocbq *pIocbIn,
                                 scsi_get_resid(cmd));
        }
 
+       lpfc_update_stats(phba, lpfc_cmd);
        result = cmd->result;
        sdev = cmd->device;
+       if (vport->cfg_max_scsicmpl_time &&
+          time_after(jiffies, lpfc_cmd->start_time +
+               msecs_to_jiffies(vport->cfg_max_scsicmpl_time))) {
+               spin_lock_irqsave(sdev->host->host_lock, flags);
+               if (pnode && NLP_CHK_NODE_ACT(pnode)) {
+                       if (pnode->cmd_qdepth >
+                               atomic_read(&pnode->cmd_pending) &&
+                               (atomic_read(&pnode->cmd_pending) >
+                               LPFC_MIN_TGT_QDEPTH) &&
+                               ((cmd->cmnd[0] == READ_10) ||
+                               (cmd->cmnd[0] == WRITE_10)))
+                               pnode->cmd_qdepth =
+                                       atomic_read(&pnode->cmd_pending);
+
+                       pnode->last_change_time = jiffies;
+               }
+               spin_unlock_irqrestore(sdev->host->host_lock, flags);
+       } else if (pnode && NLP_CHK_NODE_ACT(pnode)) {
+               if ((pnode->cmd_qdepth < LPFC_MAX_TGT_QDEPTH) &&
+                  time_after(jiffies, pnode->last_change_time +
+                             msecs_to_jiffies(LPFC_TGTQ_INTERVAL))) {
+                       spin_lock_irqsave(sdev->host->host_lock, flags);
+                       pnode->cmd_qdepth += pnode->cmd_qdepth *
+                               LPFC_TGTQ_RAMPUP_PCENT / 100;
+                       if (pnode->cmd_qdepth > LPFC_MAX_TGT_QDEPTH)
+                               pnode->cmd_qdepth = LPFC_MAX_TGT_QDEPTH;
+                       pnode->last_change_time = jiffies;
+                       spin_unlock_irqrestore(sdev->host->host_lock, flags);
+               }
+       }
+
        lpfc_scsi_unprep_dma_buf(phba, lpfc_cmd);
        cmd->scsi_done(cmd);
 
@@ -647,6 +1106,9 @@ lpfc_scsi_cmd_iocb_cmpl(struct lpfc_hba *phba, struct lpfc_iocbq *pIocbIn,
                                pnode->last_ramp_up_time = jiffies;
                        }
                }
+               lpfc_send_sdev_queuedepth_change_event(phba, vport, pnode,
+                       0xFFFFFFFF,
+                       sdev->queue_depth - 1, sdev->queue_depth);
        }
 
        /*
@@ -676,6 +1138,9 @@ lpfc_scsi_cmd_iocb_cmpl(struct lpfc_hba *phba, struct lpfc_iocbq *pIocbIn,
                        lpfc_printf_vlog(vport, KERN_WARNING, LOG_FCP,
                                         "0711 detected queue full - lun queue "
                                         "depth adjusted to %d.\n", depth);
+                       lpfc_send_sdev_queuedepth_change_event(phba, vport,
+                               pnode, 0xFFFFFFFF,
+                               depth+1, depth);
                }
        }
 
@@ -692,6 +1157,33 @@ lpfc_scsi_cmd_iocb_cmpl(struct lpfc_hba *phba, struct lpfc_iocbq *pIocbIn,
        lpfc_release_scsi_buf(phba, lpfc_cmd);
 }
 
+/**
+ * lpfc_fcpcmd_to_iocb - copy the fcp_cmd data into the IOCB.
+ * @data: A pointer to the immediate command data portion of the IOCB.
+ * @fcp_cmnd: The FCP Command that is provided by the SCSI layer.
+ *
+ * The routine copies the entire FCP command from @fcp_cmnd to @data while
+ * byte swapping the data to big endian format for transmission on the wire.
+ **/
+static void
+lpfc_fcpcmd_to_iocb(uint8_t *data, struct fcp_cmnd *fcp_cmnd)
+{
+       int i, j;
+       for (i = 0, j = 0; i < sizeof(struct fcp_cmnd);
+            i += sizeof(uint32_t), j++) {
+               ((uint32_t *)data)[j] = cpu_to_be32(((uint32_t *)fcp_cmnd)[j]);
+       }
+}
+
+/**
+ * lpfc_scsi_prep_cmnd:  Routine to convert scsi cmnd to FCP information unit.
+ * @vport: The virtual port for which this call is being executed.
+ * @lpfc_cmd: The scsi command which needs to send.
+ * @pnode: Pointer to lpfc_nodelist.
+ *
+ * This routine initializes fcp_cmnd and iocb data structure from scsi command
+ * to transfer.
+ **/
 static void
 lpfc_scsi_prep_cmnd(struct lpfc_vport *vport, struct lpfc_scsi_buf *lpfc_cmd,
                    struct lpfc_nodelist *pnode)
@@ -758,7 +1250,8 @@ lpfc_scsi_prep_cmnd(struct lpfc_vport *vport, struct lpfc_scsi_buf *lpfc_cmd,
                fcp_cmnd->fcpCntl3 = 0;
                phba->fc4ControlRequests++;
        }
-
+       if (phba->sli_rev == 3)
+               lpfc_fcpcmd_to_iocb(iocb_cmd->unsli3.fcp_ext.icd, fcp_cmnd);
        /*
         * Finish initializing those IOCB fields that are independent
         * of the scsi_cmnd request_buffer
@@ -776,6 +1269,19 @@ lpfc_scsi_prep_cmnd(struct lpfc_vport *vport, struct lpfc_scsi_buf *lpfc_cmd,
        piocbq->vport = vport;
 }
 
+/**
+ * lpfc_scsi_prep_task_mgmt_cmnd: Convert scsi TM cmnd to FCP information unit.
+ * @vport: The virtual port for which this call is being executed.
+ * @lpfc_cmd: Pointer to lpfc_scsi_buf data structure.
+ * @lun: Logical unit number.
+ * @task_mgmt_cmd: SCSI task management command.
+ *
+ * This routine creates FCP information unit corresponding to @task_mgmt_cmd.
+ *
+ * Return codes:
+ *   0 - Error
+ *   1 - Success
+ **/
 static int
 lpfc_scsi_prep_task_mgmt_cmd(struct lpfc_vport *vport,
                             struct lpfc_scsi_buf *lpfc_cmd,
@@ -798,11 +1304,13 @@ lpfc_scsi_prep_task_mgmt_cmd(struct lpfc_vport *vport,
        piocb = &piocbq->iocb;
 
        fcp_cmnd = lpfc_cmd->fcp_cmnd;
-       int_to_scsilun(lun, &lpfc_cmd->fcp_cmnd->fcp_lun);
+       /* Clear out any old data in the FCP command area */
+       memset(fcp_cmnd, 0, sizeof(struct fcp_cmnd));
+       int_to_scsilun(lun, &fcp_cmnd->fcp_lun);
        fcp_cmnd->fcpCntl2 = task_mgmt_cmd;
-
+       if (vport->phba->sli_rev == 3)
+               lpfc_fcpcmd_to_iocb(piocb->unsli3.fcp_ext.icd, fcp_cmnd);
        piocb->ulpCommand = CMD_FCP_ICMND64_CR;
-
        piocb->ulpContext = ndlp->nlp_rpi;
        if (ndlp->nlp_fcp_info & NLP_FCP_2_DEVICE) {
                piocb->ulpFCP2Rcvy = 1;
@@ -823,6 +1331,15 @@ lpfc_scsi_prep_task_mgmt_cmd(struct lpfc_vport *vport,
        return 1;
 }
 
+/**
+ * lpc_taskmgmt_def_cmpl: IOCB completion routine for task management command.
+ * @phba: The Hba for which this call is being executed.
+ * @cmdiocbq: Pointer to lpfc_iocbq data structure.
+ * @rspiocbq: Pointer to lpfc_iocbq data structure.
+ *
+ * This routine is IOCB completion routine for device reset and target reset
+ * routine. This routine release scsi buffer associated with lpfc_cmd.
+ **/
 static void
 lpfc_tskmgmt_def_cmpl(struct lpfc_hba *phba,
                        struct lpfc_iocbq *cmdiocbq,
@@ -835,6 +1352,20 @@ lpfc_tskmgmt_def_cmpl(struct lpfc_hba *phba,
        return;
 }
 
+/**
+ * lpfc_scsi_tgt_reset: Target reset handler.
+ * @lpfc_cmd: Pointer to lpfc_scsi_buf data structure
+ * @vport: The virtual port for which this call is being executed.
+ * @tgt_id: Target ID.
+ * @lun: Lun number.
+ * @rdata: Pointer to lpfc_rport_data.
+ *
+ * This routine issues a TARGET RESET iocb to reset a target with @tgt_id ID.
+ *
+ * Return Code:
+ *   0x2003 - Error
+ *   0x2002 - Success.
+ **/
 static int
 lpfc_scsi_tgt_reset(struct lpfc_scsi_buf *lpfc_cmd, struct lpfc_vport *vport,
                    unsigned  tgt_id, unsigned int lun,
@@ -888,6 +1419,15 @@ lpfc_scsi_tgt_reset(struct lpfc_scsi_buf *lpfc_cmd, struct lpfc_vport *vport,
        return ret;
 }
 
+/**
+ * lpfc_info: Info entry point of scsi_host_template data structure.
+ * @host: The scsi host for which this call is being executed.
+ *
+ * This routine provides module information about hba.
+ *
+ * Reutrn code:
+ *   Pointer to char - Success.
+ **/
 const char *
 lpfc_info(struct Scsi_Host *host)
 {
@@ -917,6 +1457,13 @@ lpfc_info(struct Scsi_Host *host)
        return lpfcinfobuf;
 }
 
+/**
+ * lpfc_poll_rearm_time: Routine to modify fcp_poll timer of hba.
+ * @phba: The Hba for which this call is being executed.
+ *
+ * This routine modifies fcp_poll_timer  field of @phba by cfg_poll_tmo.
+ * The default value of cfg_poll_tmo is 10 milliseconds.
+ **/
 static __inline__ void lpfc_poll_rearm_timer(struct lpfc_hba * phba)
 {
        unsigned long  poll_tmo_expires =
@@ -927,11 +1474,25 @@ static __inline__ void lpfc_poll_rearm_timer(struct lpfc_hba * phba)
                          poll_tmo_expires);
 }
 
+/**
+ * lpfc_poll_start_timer: Routine to start fcp_poll_timer of HBA.
+ * @phba: The Hba for which this call is being executed.
+ *
+ * This routine starts the fcp_poll_timer of @phba.
+ **/
 void lpfc_poll_start_timer(struct lpfc_hba * phba)
 {
        lpfc_poll_rearm_timer(phba);
 }
 
+/**
+ * lpfc_poll_timeout: Restart polling timer.
+ * @ptr: Map to lpfc_hba data structure pointer.
+ *
+ * This routine restarts fcp_poll timer, when FCP ring  polling is enable
+ * and FCP Ring interrupt is disable.
+ **/
+
 void lpfc_poll_timeout(unsigned long ptr)
 {
        struct lpfc_hba *phba = (struct lpfc_hba *) ptr;
@@ -943,6 +1504,20 @@ void lpfc_poll_timeout(unsigned long ptr)
        }
 }
 
+/**
+ * lpfc_queuecommand: Queuecommand entry point of Scsi Host Templater data
+ * structure.
+ * @cmnd: Pointer to scsi_cmnd data structure.
+ * @done: Pointer to done routine.
+ *
+ * Driver registers this routine to scsi midlayer to submit a @cmd to process.
+ * This routine prepares an IOCB from scsi command and provides to firmware.
+ * The @done callback is invoked after driver finished processing the command.
+ *
+ * Return value :
+ *   0 - Success
+ *   SCSI_MLQUEUE_HOST_BUSY - Block all devices served by this host temporarily.
+ **/
 static int
 lpfc_queuecommand(struct scsi_cmnd *cmnd, void (*done) (struct scsi_cmnd *))
 {
@@ -967,9 +1542,13 @@ lpfc_queuecommand(struct scsi_cmnd *cmnd, void (*done) (struct scsi_cmnd *))
         * transport is still transitioning.
         */
        if (!ndlp || !NLP_CHK_NODE_ACT(ndlp)) {
-               cmnd->result = ScsiResult(DID_BUS_BUSY, 0);
+               cmnd->result = ScsiResult(DID_TRANSPORT_DISRUPTED, 0);
                goto out_fail_command;
        }
+       if (vport->cfg_max_scsicmpl_time &&
+               (atomic_read(&ndlp->cmd_pending) >= ndlp->cmd_qdepth))
+               goto out_host_busy;
+
        lpfc_cmd = lpfc_get_scsi_buf(phba);
        if (lpfc_cmd == NULL) {
                lpfc_adjust_queue_depth(phba);
@@ -980,6 +1559,7 @@ lpfc_queuecommand(struct scsi_cmnd *cmnd, void (*done) (struct scsi_cmnd *))
                goto out_host_busy;
        }
 
+       lpfc_cmd->start_time = jiffies;
        /*
         * Store the midlayer's command structure for the completion phase
         * and complete the command initialization.
@@ -987,6 +1567,7 @@ lpfc_queuecommand(struct scsi_cmnd *cmnd, void (*done) (struct scsi_cmnd *))
        lpfc_cmd->pCmd  = cmnd;
        lpfc_cmd->rdata = rdata;
        lpfc_cmd->timeout = 0;
+       lpfc_cmd->start_time = jiffies;
        cmnd->host_scribble = (unsigned char *)lpfc_cmd;
        cmnd->scsi_done = done;
 
@@ -996,6 +1577,7 @@ lpfc_queuecommand(struct scsi_cmnd *cmnd, void (*done) (struct scsi_cmnd *))
 
        lpfc_scsi_prep_cmnd(vport, lpfc_cmd, ndlp);
 
+       atomic_inc(&ndlp->cmd_pending);
        err = lpfc_sli_issue_iocb(phba, &phba->sli.ring[psli->fcp_ring],
                                  &lpfc_cmd->cur_iocbq, SLI_IOCB_RET_IOCB);
        if (err)
@@ -1010,6 +1592,7 @@ lpfc_queuecommand(struct scsi_cmnd *cmnd, void (*done) (struct scsi_cmnd *))
        return 0;
 
  out_host_busy_free_buf:
+       atomic_dec(&ndlp->cmd_pending);
        lpfc_scsi_unprep_dma_buf(phba, lpfc_cmd);
        lpfc_release_scsi_buf(phba, lpfc_cmd);
  out_host_busy:
@@ -1020,6 +1603,12 @@ lpfc_queuecommand(struct scsi_cmnd *cmnd, void (*done) (struct scsi_cmnd *))
        return 0;
 }
 
+/**
+ * lpfc_block_error_handler: Routine to block error  handler.
+ * @cmnd: Pointer to scsi_cmnd data structure.
+ *
+ *  This routine blocks execution till fc_rport state is not FC_PORSTAT_BLCOEKD.
+ **/
 static void
 lpfc_block_error_handler(struct scsi_cmnd *cmnd)
 {
@@ -1036,6 +1625,17 @@ lpfc_block_error_handler(struct scsi_cmnd *cmnd)
        return;
 }
 
+/**
+ * lpfc_abort_handler: Eh_abort_handler entry point of Scsi Host Template data
+ *structure.
+ * @cmnd: Pointer to scsi_cmnd data structure.
+ *
+ * This routine aborts @cmnd pending in base driver.
+ *
+ * Return code :
+ *   0x2003 - Error
+ *   0x2002 - Success
+ **/
 static int
 lpfc_abort_handler(struct scsi_cmnd *cmnd)
 {
@@ -1131,6 +1731,18 @@ lpfc_abort_handler(struct scsi_cmnd *cmnd)
        return ret;
 }
 
+/**
+ * lpfc_device_reset_handler: eh_device_reset entry point of Scsi Host Template
+ *data structure.
+ * @cmnd: Pointer to scsi_cmnd data structure.
+ *
+ * This routine does a device reset by sending a TARGET_RESET task management
+ * command.
+ *
+ * Return code :
+ *  0x2003 - Error
+ *  0ex2002 - Success
+ **/
 static int
 lpfc_device_reset_handler(struct scsi_cmnd *cmnd)
 {
@@ -1145,6 +1757,7 @@ lpfc_device_reset_handler(struct scsi_cmnd *cmnd)
        int ret = SUCCESS;
        int status;
        int cnt;
+       struct lpfc_scsi_event_header scsi_event;
 
        lpfc_block_error_handler(cmnd);
        /*
@@ -1163,6 +1776,19 @@ lpfc_device_reset_handler(struct scsi_cmnd *cmnd)
                        break;
                pnode = rdata->pnode;
        }
+
+       scsi_event.event_type = FC_REG_SCSI_EVENT;
+       scsi_event.subcategory = LPFC_EVENT_TGTRESET;
+       scsi_event.lun = 0;
+       memcpy(scsi_event.wwpn, &pnode->nlp_portname, sizeof(struct lpfc_name));
+       memcpy(scsi_event.wwnn, &pnode->nlp_nodename, sizeof(struct lpfc_name));
+
+       fc_host_post_vendor_event(shost,
+               fc_get_event_number(),
+               sizeof(scsi_event),
+               (char *)&scsi_event,
+               LPFC_NL_VENDOR_ID);
+
        if (!rdata || pnode->nlp_state != NLP_STE_MAPPED_NODE) {
                lpfc_printf_vlog(vport, KERN_ERR, LOG_FCP,
                                 "0721 LUN Reset rport "
@@ -1234,6 +1860,17 @@ lpfc_device_reset_handler(struct scsi_cmnd *cmnd)
        return ret;
 }
 
+/**
+ * lpfc_bus_reset_handler: eh_bus_reset_handler entry point of Scsi Host
+ * Template data structure.
+ * @cmnd: Pointer to scsi_cmnd data structure.
+ *
+ * This routine does target reset to all target on @cmnd->device->host.
+ *
+ * Return Code:
+ *   0x2003 - Error
+ *   0x2002 - Success
+ **/
 static int
 lpfc_bus_reset_handler(struct scsi_cmnd *cmnd)
 {
@@ -1242,10 +1879,23 @@ lpfc_bus_reset_handler(struct scsi_cmnd *cmnd)
        struct lpfc_hba   *phba = vport->phba;
        struct lpfc_nodelist *ndlp = NULL;
        int match;
-       int ret = SUCCESS, status, i;
+       int ret = SUCCESS, status = SUCCESS, i;
        int cnt;
        struct lpfc_scsi_buf * lpfc_cmd;
        unsigned long later;
+       struct lpfc_scsi_event_header scsi_event;
+
+       scsi_event.event_type = FC_REG_SCSI_EVENT;
+       scsi_event.subcategory = LPFC_EVENT_BUSRESET;
+       scsi_event.lun = 0;
+       memcpy(scsi_event.wwpn, &vport->fc_portname, sizeof(struct lpfc_name));
+       memcpy(scsi_event.wwnn, &vport->fc_nodename, sizeof(struct lpfc_name));
+
+       fc_host_post_vendor_event(shost,
+               fc_get_event_number(),
+               sizeof(scsi_event),
+               (char *)&scsi_event,
+               LPFC_NL_VENDOR_ID);
 
        lpfc_block_error_handler(cmnd);
        /*
@@ -1311,6 +1961,20 @@ lpfc_bus_reset_handler(struct scsi_cmnd *cmnd)
        return ret;
 }
 
+/**
+ * lpfc_slave_alloc: slave_alloc entry point of Scsi Host Template data
+ * structure.
+ * @sdev: Pointer to scsi_device.
+ *
+ * This routine populates the cmds_per_lun count + 2 scsi_bufs into  this host's
+ * globally available list of scsi buffers. This routine also makes sure scsi
+ * buffer is not allocated more than HBA limit conveyed to midlayer. This list
+ * of scsi buffer exists for the lifetime of the driver.
+ *
+ * Return codes:
+ *   non-0 - Error
+ *   0 - Success
+ **/
 static int
 lpfc_slave_alloc(struct scsi_device *sdev)
 {
@@ -1372,6 +2036,19 @@ lpfc_slave_alloc(struct scsi_device *sdev)
        return 0;
 }
 
+/**
+ * lpfc_slave_configure: slave_configure entry point of Scsi Host Templater data
+ *  structure.
+ * @sdev: Pointer to scsi_device.
+ *
+ * This routine configures following items
+ *   - Tag command queuing support for @sdev if supported.
+ *   - Dev loss time out value of fc_rport.
+ *   - Enable SLI polling for fcp ring if ENABLE_FCP_RING_POLLING flag is set.
+ *
+ * Return codes:
+ *   0 - Success
+ **/
 static int
 lpfc_slave_configure(struct scsi_device *sdev)
 {
@@ -1401,6 +2078,12 @@ lpfc_slave_configure(struct scsi_device *sdev)
        return 0;
 }
 
+/**
+ * lpfc_slave_destroy: slave_destroy entry point of SHT data structure.
+ * @sdev: Pointer to scsi_device.
+ *
+ * This routine sets @sdev hostatdata filed to null.
+ **/
 static void
 lpfc_slave_destroy(struct scsi_device *sdev)
 {