lpfc: Add support for using block multi-queue

With blk-mq support in the mid-layer, lpfc can do IO steering based
on the information in the request tag.  This patch allows lpfc to use
blk-mq if enabled. If not enabled, we fall back into the emulex-internal
affinity mappings.

This feature can be turned on via CONFIG_SCSI_MQ_DEFAULT or passing
scsi_mod.use_blk_mq=Y as a parameter to the kernel.

Signed-off-by: Dick Kennedy <dick.kennedy@avagotech.com>
Signed-off-by: James Smart <james.smart@avagotech.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
diff --git a/drivers/scsi/lpfc/lpfc_init.c b/drivers/scsi/lpfc/lpfc_init.c
index 14424e6..f962118 100644
--- a/drivers/scsi/lpfc/lpfc_init.c
+++ b/drivers/scsi/lpfc/lpfc_init.c
@@ -3303,6 +3303,7 @@
 	shost->max_lun = vport->cfg_max_luns;
 	shost->this_id = -1;
 	shost->max_cmd_len = 16;
+	shost->nr_hw_queues = phba->cfg_fcp_io_channel;
 	if (phba->sli_rev == LPFC_SLI_REV4) {
 		shost->dma_boundary =
 			phba->sli4_hba.pc_sli4_params.sge_supp_len-1;
@@ -8980,7 +8981,8 @@
 		phba->cfg_fcp_io_channel = vectors;
 	}
 
-	lpfc_sli4_set_affinity(phba, vectors);
+	if (!shost_use_blk_mq(lpfc_shost_from_vport(phba->pport)))
+		lpfc_sli4_set_affinity(phba, vectors);
 	return rc;
 
 cfg_fail_out: