[SCSI] lpfc 8.3.45: Incorporated support of a low-latency io path

Signed-off-by: James Smart <james.smart@emulex.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

drivers/scsi/lpfc/lpfc_scsi.c

@@ -68,6 +68,17 @@ struct scsi_dif_tuple {
 	__be32 ref_tag;         /* Target LBA or indirect LBA */
 };
 
+static struct lpfc_rport_data *
+lpfc_rport_data_from_scsi_device(struct scsi_device *sdev)
+{
+	struct lpfc_vport *vport = (struct lpfc_vport *)sdev->host->hostdata;
+
+	if (vport->phba->cfg_EnableXLane)
+		return ((struct lpfc_device_data *)sdev->hostdata)->rport_data;
+	else
+		return (struct lpfc_rport_data *)sdev->hostdata;
+}
+
 static void
 lpfc_release_scsi_buf_s4(struct lpfc_hba *phba, struct lpfc_scsi_buf *psb);
 static void
@@ -306,7 +317,7 @@ lpfc_change_queue_depth(struct scsi_device *sdev, int qdepth, int reason)
 	old_queue_depth = sdev->queue_depth;
 	scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth);
 	new_queue_depth = sdev->queue_depth;
-	rdata = sdev->hostdata;
+	rdata = lpfc_rport_data_from_scsi_device(sdev);
 	if (rdata)
 		lpfc_send_sdev_queuedepth_change_event(phba, vport,
 						       rdata->pnode, sdev->lun,
@@ -1502,7 +1513,7 @@ lpfc_bg_err_inject(struct lpfc_hba *phba, struct scsi_cmnd *sc,
 	}
 
 	/* Next check if we need to match the remote NPortID or WWPN */
-	rdata = sc->device->hostdata;
+	rdata = lpfc_rport_data_from_scsi_device(sc->device);
 	if (rdata && rdata->pnode) {
 		ndlp = rdata->pnode;
 
@@ -3507,6 +3518,14 @@ lpfc_scsi_prep_dma_buf_s4(struct lpfc_hba *phba, struct lpfc_scsi_buf *lpfc_cmd)
 	 * we need to set word 4 of IOCB here
 	 */
 	iocb_cmd->un.fcpi.fcpi_parm = scsi_bufflen(scsi_cmnd);
+
+	/*
+	 * If the OAS driver feature is enabled and the lun is enabled for
+	 * OAS, set the oas iocb related flags.
+	 */
+	if ((phba->cfg_EnableXLane) && ((struct lpfc_device_data *)
+		scsi_cmnd->device->hostdata)->oas_enabled)
+		lpfc_cmd->cur_iocbq.iocb_flag |= LPFC_IO_OAS;
 	return 0;
 }
 
@@ -4691,12 +4710,13 @@ lpfc_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *cmnd)
 {
 	struct lpfc_vport *vport = (struct lpfc_vport *) shost->hostdata;
 	struct lpfc_hba   *phba = vport->phba;
-	struct lpfc_rport_data *rdata = cmnd->device->hostdata;
+	struct lpfc_rport_data *rdata;
 	struct lpfc_nodelist *ndlp;
 	struct lpfc_scsi_buf *lpfc_cmd;
 	struct fc_rport *rport = starget_to_rport(scsi_target(cmnd->device));
 	int err;
 
+	rdata = lpfc_rport_data_from_scsi_device(cmnd->device);
 	err = fc_remote_port_chkready(rport);
 	if (err) {
 		cmnd->result = err;
@@ -5179,10 +5199,11 @@ lpfc_send_taskmgmt(struct lpfc_vport *vport, struct lpfc_rport_data *rdata,
 static int
 lpfc_chk_tgt_mapped(struct lpfc_vport *vport, struct scsi_cmnd *cmnd)
 {
-	struct lpfc_rport_data *rdata = cmnd->device->hostdata;
+	struct lpfc_rport_data *rdata;
 	struct lpfc_nodelist *pnode;
 	unsigned long later;
 
+	rdata = lpfc_rport_data_from_scsi_device(cmnd->device);
 	if (!rdata) {
 		lpfc_printf_vlog(vport, KERN_INFO, LOG_FCP,
 			"0797 Tgt Map rport failure: rdata x%p\n", rdata);
@@ -5200,7 +5221,7 @@ lpfc_chk_tgt_mapped(struct lpfc_vport *vport, struct scsi_cmnd *cmnd)
 		if (pnode->nlp_state == NLP_STE_MAPPED_NODE)
 			return SUCCESS;
 		schedule_timeout_uninterruptible(msecs_to_jiffies(500));
-		rdata = cmnd->device->hostdata;
+		rdata = lpfc_rport_data_from_scsi_device(cmnd->device);
 		if (!rdata)
 			return FAILED;
 		pnode = rdata->pnode;
@@ -5272,13 +5293,14 @@ lpfc_device_reset_handler(struct scsi_cmnd *cmnd)
 {
 	struct Scsi_Host  *shost = cmnd->device->host;
 	struct lpfc_vport *vport = (struct lpfc_vport *) shost->hostdata;
-	struct lpfc_rport_data *rdata = cmnd->device->hostdata;
+	struct lpfc_rport_data *rdata;
 	struct lpfc_nodelist *pnode;
 	unsigned tgt_id = cmnd->device->id;
 	unsigned int lun_id = cmnd->device->lun;
 	struct lpfc_scsi_event_header scsi_event;
 	int status;
 
+	rdata = lpfc_rport_data_from_scsi_device(cmnd->device);
 	if (!rdata) {
 		lpfc_printf_vlog(vport, KERN_ERR, LOG_FCP,
 			"0798 Device Reset rport failure: rdata x%p\n", rdata);
@@ -5341,13 +5363,14 @@ lpfc_target_reset_handler(struct scsi_cmnd *cmnd)
 {
 	struct Scsi_Host  *shost = cmnd->device->host;
 	struct lpfc_vport *vport = (struct lpfc_vport *) shost->hostdata;
-	struct lpfc_rport_data *rdata = cmnd->device->hostdata;
+	struct lpfc_rport_data *rdata;
 	struct lpfc_nodelist *pnode;
 	unsigned tgt_id = cmnd->device->id;
 	unsigned int lun_id = cmnd->device->lun;
 	struct lpfc_scsi_event_header scsi_event;
 	int status;
 
+	rdata = lpfc_rport_data_from_scsi_device(cmnd->device);
 	if (!rdata) {
 		lpfc_printf_vlog(vport, KERN_ERR, LOG_FCP,
 			"0799 Target Reset rport failure: rdata x%p\n", rdata);
@@ -5547,11 +5570,45 @@ lpfc_slave_alloc(struct scsi_device *sdev)
 	uint32_t num_to_alloc = 0;
 	int num_allocated = 0;
 	uint32_t sdev_cnt;
+	struct lpfc_device_data *device_data;
+	unsigned long flags;
+	struct lpfc_name target_wwpn;
 
 	if (!rport || fc_remote_port_chkready(rport))
 		return -ENXIO;
 
-	sdev->hostdata = rport->dd_data;
+	if (phba->cfg_EnableXLane) {
+
+		/*
+		 * Check to see if the device data structure for the lun
+		 * exists.  If not, create one.
+		 */
+
+		u64_to_wwn(rport->port_name, target_wwpn.u.wwn);
+		spin_lock_irqsave(&phba->devicelock, flags);
+		device_data = __lpfc_get_device_data(phba,
+						     &phba->luns,
+						     &vport->fc_portname,
+						     &target_wwpn,
+						     sdev->lun);
+		if (!device_data) {
+			spin_unlock_irqrestore(&phba->devicelock, flags);
+			device_data = lpfc_create_device_data(phba,
+							&vport->fc_portname,
+							&target_wwpn,
+							sdev->lun, true);
+			if (!device_data)
+				return -ENOMEM;
+			spin_lock_irqsave(&phba->devicelock, flags);
+			list_add_tail(&device_data->listentry, &phba->luns);
+		}
+		device_data->rport_data = rport->dd_data;
+		device_data->available = true;
+		spin_unlock_irqrestore(&phba->devicelock, flags);
+		sdev->hostdata = device_data;
+	} else {
+		sdev->hostdata = rport->dd_data;
+	}
 	sdev_cnt = atomic_inc_return(&phba->sdev_cnt);
 
 	/*
@@ -5641,11 +5698,344 @@ lpfc_slave_destroy(struct scsi_device *sdev)
 {
 	struct lpfc_vport *vport = (struct lpfc_vport *) sdev->host->hostdata;
 	struct lpfc_hba   *phba = vport->phba;
+	unsigned long flags;
+	struct lpfc_device_data *device_data = sdev->hostdata;
+
 	atomic_dec(&phba->sdev_cnt);
+	if ((phba->cfg_EnableXLane) && (device_data)) {
+		spin_lock_irqsave(&phba->devicelock, flags);
+		device_data->available = false;
+		if (!device_data->oas_enabled)
+			lpfc_delete_device_data(phba, device_data);
+		spin_unlock_irqrestore(&phba->devicelock, flags);
+	}
 	sdev->hostdata = NULL;
 	return;
 }
 
+/**
+ * lpfc_create_device_data - creates and initializes device data structure for OAS
+ * @pha: Pointer to host bus adapter structure.
+ * @vport_wwpn: Pointer to vport's wwpn information
+ * @target_wwpn: Pointer to target's wwpn information
+ * @lun: Lun on target
+ * @atomic_create: Flag to indicate if memory should be allocated using the
+ *		  GFP_ATOMIC flag or not.
+ *
+ * This routine creates a device data structure which will contain identifying
+ * information for the device (host wwpn, target wwpn, lun), state of OAS,
+ * whether or not the corresponding lun is available by the system,
+ * and pointer to the rport data.
+ *
+ * Return codes:
+ *   NULL - Error
+ *   Pointer to lpfc_device_data - Success
+ **/
+struct lpfc_device_data*
+lpfc_create_device_data(struct lpfc_hba *phba, struct lpfc_name *vport_wwpn,
+			struct lpfc_name *target_wwpn, uint64_t lun,
+			bool atomic_create)
+{
+
+	struct lpfc_device_data *lun_info;
+	int memory_flags;
+
+	if (unlikely(!phba) || !vport_wwpn || !target_wwpn  ||
+	    !(phba->cfg_EnableXLane))
+		return NULL;
+
+	/* Attempt to create the device data to contain lun info */
+
+	if (atomic_create)
+		memory_flags = GFP_ATOMIC;
+	else
+		memory_flags = GFP_KERNEL;
+	lun_info = mempool_alloc(phba->device_data_mem_pool, memory_flags);
+	if (!lun_info)
+		return NULL;
+	INIT_LIST_HEAD(&lun_info->listentry);
+	lun_info->rport_data  = NULL;
+	memcpy(&lun_info->device_id.vport_wwpn, vport_wwpn,
+	       sizeof(struct lpfc_name));
+	memcpy(&lun_info->device_id.target_wwpn, target_wwpn,
+	       sizeof(struct lpfc_name));
+	lun_info->device_id.lun = lun;
+	lun_info->oas_enabled = false;
+	lun_info->available = false;
+	return lun_info;
+}
+
+/**
+ * lpfc_delete_device_data - frees a device data structure for OAS
+ * @pha: Pointer to host bus adapter structure.
+ * @lun_info: Pointer to device data structure to free.
+ *
+ * This routine frees the previously allocated device data structure passed.
+ *
+ **/
+void
+lpfc_delete_device_data(struct lpfc_hba *phba,
+			struct lpfc_device_data *lun_info)
+{
+
+	if (unlikely(!phba) || !lun_info  ||
+	    !(phba->cfg_EnableXLane))
+		return;
+
+	if (!list_empty(&lun_info->listentry))
+		list_del(&lun_info->listentry);
+	mempool_free(lun_info, phba->device_data_mem_pool);
+	return;
+}
+
+/**
+ * __lpfc_get_device_data - returns the device data for the specified lun
+ * @pha: Pointer to host bus adapter structure.
+ * @list: Point to list to search.
+ * @vport_wwpn: Pointer to vport's wwpn information
+ * @target_wwpn: Pointer to target's wwpn information
+ * @lun: Lun on target
+ *
+ * This routine searches the list passed for the specified lun's device data.
+ * This function does not hold locks, it is the responsibility of the caller
+ * to ensure the proper lock is held before calling the function.
+ *
+ * Return codes:
+ *   NULL - Error
+ *   Pointer to lpfc_device_data - Success
+ **/
+struct lpfc_device_data*
+__lpfc_get_device_data(struct lpfc_hba *phba, struct list_head *list,
+		       struct lpfc_name *vport_wwpn,
+		       struct lpfc_name *target_wwpn, uint64_t lun)
+{
+
+	struct lpfc_device_data *lun_info;
+
+	if (unlikely(!phba) || !list || !vport_wwpn || !target_wwpn ||
+	    !phba->cfg_EnableXLane)
+		return NULL;
+
+	/* Check to see if the lun is already enabled for OAS. */
+
+	list_for_each_entry(lun_info, list, listentry) {
+		if ((memcmp(&lun_info->device_id.vport_wwpn, vport_wwpn,
+			    sizeof(struct lpfc_name)) == 0) &&
+		    (memcmp(&lun_info->device_id.target_wwpn, target_wwpn,
+			    sizeof(struct lpfc_name)) == 0) &&
+		    (lun_info->device_id.lun == lun))
+			return lun_info;
+	}
+
+	return NULL;
+}
+
+/**
+ * lpfc_find_next_oas_lun - searches for the next oas lun
+ * @pha: Pointer to host bus adapter structure.
+ * @vport_wwpn: Pointer to vport's wwpn information
+ * @target_wwpn: Pointer to target's wwpn information
+ * @starting_lun: Pointer to the lun to start searching for
+ * @found_vport_wwpn: Pointer to the found lun's vport wwpn information
+ * @found_target_wwpn: Pointer to the found lun's target wwpn information
+ * @found_lun: Pointer to the found lun.
+ * @found_lun_status: Pointer to status of the found lun.
+ *
+ * This routine searches the luns list for the specified lun
+ * or the first lun for the vport/target.  If the vport wwpn contains
+ * a zero value then a specific vport is not specified. In this case
+ * any vport which contains the lun will be considered a match.  If the
+ * target wwpn contains a zero value then a specific target is not specified.
+ * In this case any target which contains the lun will be considered a
+ * match.  If the lun is found, the lun, vport wwpn, target wwpn and lun status
+ * are returned.  The function will also return the next lun if available.
+ * If the next lun is not found, starting_lun parameter will be set to
+ * NO_MORE_OAS_LUN.
+ *
+ * Return codes:
+ *   non-0 - Error
+ *   0 - Success
+ **/
+bool
+lpfc_find_next_oas_lun(struct lpfc_hba *phba, struct lpfc_name *vport_wwpn,
+		       struct lpfc_name *target_wwpn, uint64_t *starting_lun,
+		       struct lpfc_name *found_vport_wwpn,
+		       struct lpfc_name *found_target_wwpn,
+		       uint64_t *found_lun,
+		       uint32_t *found_lun_status)
+{
+
+	unsigned long flags;
+	struct lpfc_device_data *lun_info;
+	struct lpfc_device_id *device_id;
+	uint64_t lun;
+	bool found = false;
+
+	if (unlikely(!phba) || !vport_wwpn || !target_wwpn ||
+	    !starting_lun || !found_vport_wwpn ||
+	    !found_target_wwpn || !found_lun || !found_lun_status ||
+	    (*starting_lun == NO_MORE_OAS_LUN) ||
+	    !phba->cfg_EnableXLane)
+		return false;
+
+	lun = *starting_lun;
+	*found_lun = NO_MORE_OAS_LUN;
+	*starting_lun = NO_MORE_OAS_LUN;
+
+	/* Search for lun or the lun closet in value */
+
+	spin_lock_irqsave(&phba->devicelock, flags);
+	list_for_each_entry(lun_info, &phba->luns, listentry) {
+		if (((wwn_to_u64(vport_wwpn->u.wwn) == 0) ||
+		     (memcmp(&lun_info->device_id.vport_wwpn, vport_wwpn,
+			    sizeof(struct lpfc_name)) == 0)) &&
+		    ((wwn_to_u64(target_wwpn->u.wwn) == 0) ||
+		     (memcmp(&lun_info->device_id.target_wwpn, target_wwpn,
+			    sizeof(struct lpfc_name)) == 0)) &&
+		    (lun_info->oas_enabled)) {
+			device_id = &lun_info->device_id;
+			if ((!found) &&
+			    ((lun == FIND_FIRST_OAS_LUN) ||
+			     (device_id->lun == lun))) {
+				*found_lun = device_id->lun;
+				memcpy(found_vport_wwpn,
+				       &device_id->vport_wwpn,
+				       sizeof(struct lpfc_name));
+				memcpy(found_target_wwpn,
+				       &device_id->target_wwpn,
+				       sizeof(struct lpfc_name));
+				if (lun_info->available)
+					*found_lun_status =
+						OAS_LUN_STATUS_EXISTS;
+				else
+					*found_lun_status = 0;
+				if (phba->cfg_oas_flags & OAS_FIND_ANY_VPORT)
+					memset(vport_wwpn, 0x0,
+					       sizeof(struct lpfc_name));
+				if (phba->cfg_oas_flags & OAS_FIND_ANY_TARGET)
+					memset(target_wwpn, 0x0,
+					       sizeof(struct lpfc_name));
+				found = true;
+			} else if (found) {
+				*starting_lun = device_id->lun;
+				memcpy(vport_wwpn, &device_id->vport_wwpn,
+				       sizeof(struct lpfc_name));
+				memcpy(target_wwpn, &device_id->target_wwpn,
+				       sizeof(struct lpfc_name));
+				break;
+			}
+		}
+	}
+	spin_unlock_irqrestore(&phba->devicelock, flags);
+	return found;
+}
+
+/**
+ * lpfc_enable_oas_lun - enables a lun for OAS operations
+ * @pha: Pointer to host bus adapter structure.
+ * @vport_wwpn: Pointer to vport's wwpn information
+ * @target_wwpn: Pointer to target's wwpn information
+ * @lun: Lun
+ *
+ * This routine enables a lun for oas operations.  The routines does so by
+ * doing the following :
+ *
+ *   1) Checks to see if the device data for the lun has been created.
+ *   2) If found, sets the OAS enabled flag if not set and returns.
+ *   3) Otherwise, creates a device data structure.
+ *   4) If successfully created, indicates the device data is for an OAS lun,
+ *   indicates the lun is not available and add to the list of luns.
+ *
+ * Return codes:
+ *   false - Error
+ *   true - Success
+ **/
+bool
+lpfc_enable_oas_lun(struct lpfc_hba *phba, struct lpfc_name *vport_wwpn,
+		    struct lpfc_name *target_wwpn, uint64_t lun)
+{
+
+	struct lpfc_device_data *lun_info;
+	unsigned long flags;
+
+	if (unlikely(!phba) || !vport_wwpn || !target_wwpn ||
+	    !phba->cfg_EnableXLane)
+		return false;
+
+	spin_lock_irqsave(&phba->devicelock, flags);
+
+	/* Check to see if the device data for the lun has been created */
+	lun_info = __lpfc_get_device_data(phba, &phba->luns, vport_wwpn,
+					  target_wwpn, lun);
+	if (lun_info) {
+		if (!lun_info->oas_enabled)
+			lun_info->oas_enabled = true;
+		spin_unlock_irqrestore(&phba->devicelock, flags);
+		return true;
+	}
+
+	/* Create an lun info structure and add to list of luns */
+	lun_info = lpfc_create_device_data(phba, vport_wwpn, target_wwpn, lun,
+					   false);
+	if (lun_info) {
+		lun_info->oas_enabled = true;
+		lun_info->available = false;
+		list_add_tail(&lun_info->listentry, &phba->luns);
+		spin_unlock_irqrestore(&phba->devicelock, flags);
+		return true;
+	}
+	spin_unlock_irqrestore(&phba->devicelock, flags);
+	return false;
+}
+
+/**
+ * lpfc_disable_oas_lun - disables a lun for OAS operations
+ * @pha: Pointer to host bus adapter structure.
+ * @vport_wwpn: Pointer to vport's wwpn information
+ * @target_wwpn: Pointer to target's wwpn information
+ * @lun: Lun
+ *
+ * This routine disables a lun for oas operations.  The routines does so by
+ * doing the following :
+ *
+ *   1) Checks to see if the device data for the lun is created.
+ *   2) If present, clears the flag indicating this lun is for OAS.
+ *   3) If the lun is not available by the system, the device data is
+ *   freed.
+ *
+ * Return codes:
+ *   false - Error
+ *   true - Success
+ **/
+bool
+lpfc_disable_oas_lun(struct lpfc_hba *phba, struct lpfc_name *vport_wwpn,
+		     struct lpfc_name *target_wwpn, uint64_t lun)
+{
+
+	struct lpfc_device_data *lun_info;
+	unsigned long flags;
+
+	if (unlikely(!phba) || !vport_wwpn || !target_wwpn ||
+	    !phba->cfg_EnableXLane)
+		return false;
+
+	spin_lock_irqsave(&phba->devicelock, flags);
+
+	/* Check to see if the lun is available. */
+	lun_info = __lpfc_get_device_data(phba,
+					  &phba->luns, vport_wwpn,
+					  target_wwpn, lun);
+	if (lun_info) {
+		lun_info->oas_enabled = false;
+		if (!lun_info->available)
+			lpfc_delete_device_data(phba, lun_info);
+		spin_unlock_irqrestore(&phba->devicelock, flags);
+		return true;
+	}
+
+	spin_unlock_irqrestore(&phba->devicelock, flags);
+	return false;
+}
 
 struct scsi_host_template lpfc_template = {
 	.module			= THIS_MODULE,