diff --git a/drivers/scsi/qla2xxx/qla_mbx.c b/drivers/scsi/qla2xxx/qla_mbx.c
index 39544deab576..59ec5605930b 100644
--- a/drivers/scsi/qla2xxx/qla_mbx.c
+++ b/drivers/scsi/qla2xxx/qla_mbx.c
@@ -6579,6 +6579,7 @@ qla26xx_dport_diagnostics(scsi_qla_host_t *vha,
 	mbx_cmd_t mc;
 	mbx_cmd_t *mcp = &mc;
 	dma_addr_t dd_dma;
+	void *dd;
 
 	if (!IS_QLA83XX(vha->hw) && !IS_QLA27XX(vha->hw) &&
 	    !IS_QLA28XX(vha->hw) && !IS_QLA29XX(vha->hw))
@@ -6587,15 +6588,12 @@ qla26xx_dport_diagnostics(scsi_qla_host_t *vha,
 	ql_dbg(ql_dbg_mbx + ql_dbg_verbose, vha, 0x119f,
 	    "Entered %s.\n", __func__);
 
-	dd_dma = dma_map_single(&vha->hw->pdev->dev,
-	    dd_buf, size, DMA_FROM_DEVICE);
-	if (dma_mapping_error(&vha->hw->pdev->dev, dd_dma)) {
-		ql_log(ql_log_warn, vha, 0x1194, "Failed to map dma buffer.\n");
+	dd = dma_alloc_coherent(&vha->hw->pdev->dev, size, &dd_dma, GFP_KERNEL);
+	if (!dd) {
+		ql_log(ql_log_warn, vha, 0x1194, "Failed to allocate dma buffer.\n");
 		return QLA_MEMORY_ALLOC_FAILED;
 	}
 
-	memset(dd_buf, 0, size);
-
 	mcp->mb[0] = MBC_DPORT_DIAGNOSTICS;
 	mcp->mb[1] = options;
 	mcp->mb[2] = MSW(LSD(dd_dma));
@@ -6617,8 +6615,9 @@ qla26xx_dport_diagnostics(scsi_qla_host_t *vha,
 		    "Done %s.\n", __func__);
 	}
 
-	dma_unmap_single(&vha->hw->pdev->dev, dd_dma,
-	    size, DMA_FROM_DEVICE);
+	memcpy(dd_buf, dd, size);
+
+	dma_free_coherent(&vha->hw->pdev->dev, size, dd, dd_dma);
 
 	return rval;
 }