Re: dma related cleanups for wd719x

[Ondrej Zary <linux@xxxxxxxxxxxxxxxxxxxx>]

On Thursday 18 October 2018 15:01:14 Christoph Hellwig wrote:
> Hi Ondrej,
> 
> can you look over this series, which cleans up a few dma-related
> bits in the wd719x driver?
 
Hello,
this patch is needed to make it work:

diff --git a/drivers/scsi/wd719x.c b/drivers/scsi/wd719x.c
index d47190f08ed6..b73e7f24a1c4 100644
--- a/drivers/scsi/wd719x.c
+++ b/drivers/scsi/wd719x.c
@@ -183,7 +183,7 @@ static void wd719x_finish_cmd(struct wd719x_scb *scb, int result)
 	list_del(&scb->list);
 
 	dma_unmap_single(&wd->pdev->dev, scb->phys,
-			sizeof(struct wd719x_scb), DMA_TO_DEVICE);
+			sizeof(struct wd719x_scb), DMA_BIDIRECTIONAL);
 	scsi_dma_unmap(cmd);
 	dma_unmap_single(&wd->pdev->dev, cmd->SCp.dma_handle,
 			 SCSI_SENSE_BUFFERSIZE, DMA_FROM_DEVICE);
@@ -209,12 +209,19 @@ static int wd719x_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *cmd)
 	/* copy the command */
 	memcpy(scb->CDB, cmd->cmnd, cmd->cmd_len);
 
+	/* map SCB */
+	scb->phys = dma_map_single(&wd->pdev->dev, scb, sizeof(*scb),
+				   DMA_BIDIRECTIONAL);
+
+	if (dma_mapping_error(&wd->pdev->dev, scb->phys))
+		goto out_error;
+
 	/* map sense buffer */
 	scb->sense_buf_length = SCSI_SENSE_BUFFERSIZE;
 	cmd->SCp.dma_handle = dma_map_single(&wd->pdev->dev, cmd->sense_buffer,
 			SCSI_SENSE_BUFFERSIZE, DMA_FROM_DEVICE);
 	if (dma_mapping_error(&wd->pdev->dev, cmd->SCp.dma_handle))
-		goto out_error;
+		goto out_unmap_scb;
 	scb->sense_buf = cpu_to_le32(cmd->SCp.dma_handle);
 
 	/* request autosense */
@@ -246,11 +253,6 @@ static int wd719x_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *cmd)
 			scb->sg_list[i].length = cpu_to_le32(sg_dma_len(sg));
 		}
 		scb->SCB_options |= WD719X_SCB_FLAGS_DO_SCATTER_GATHER;
-
-		scb->phys = dma_map_single(&wd->pdev->dev, scb, sizeof(*scb),
-					   DMA_TO_DEVICE);
-		if (dma_mapping_error(&wd->pdev->dev, scb->phys))
-			goto out_unmap_scsi_cmd;
 	} else { /* zero length */
 		scb->data_length = 0;
 		scb->data_p = 0;
@@ -274,11 +276,12 @@ static int wd719x_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *cmd)
 	spin_unlock_irqrestore(wd->sh->host_lock, flags);
 	return 0;
 
-out_unmap_scsi_cmd:
-	scsi_dma_unmap(cmd);
 out_unmap_sense:
 	dma_unmap_single(&wd->pdev->dev, cmd->SCp.dma_handle,
 			 SCSI_SENSE_BUFFERSIZE, DMA_FROM_DEVICE);
+out_unmap_scb:
+	dma_unmap_single(&wd->pdev->dev, scb->phys, sizeof(*scb),
+			 DMA_BIDIRECTIONAL);
 out_error:
 	cmd->result = DID_ERROR << 16;
 	cmd->scsi_done(cmd);


-- 
Ondrej Zary