scsi: hisi_sas: Drop SMP resp frame DMA mapping

The SMP frame response is written to the command table and not the SMP
response pointer from libsas, so don't bother DMA mapping (and unmapping)
the SMP response from libsas.

Suggested-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 7 insertions, 21 deletions

diff --git a/drivers/scsi/hisi_sas/hisi_sas_main.c b/drivers/scsi/hisi_sas/hisi_sas_main.c
index 39ae69e42d26..a2255701b50b 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_main.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_main.c
@@ -300,7 +300,7 @@ static void hisi_sas_task_prep_abort(struct hisi_hba *hisi_hba,
 
 static void hisi_sas_dma_unmap(struct hisi_hba *hisi_hba,
 			       struct sas_task *task, int n_elem,
-			       int n_elem_req, int n_elem_resp)
+			       int n_elem_req)
 {
 	struct device *dev = hisi_hba->dev;
 
@@ -314,16 +314,13 @@ static void hisi_sas_dma_unmap(struct hisi_hba *hisi_hba,
 			if (n_elem_req)
 				dma_unmap_sg(dev, &task->smp_task.smp_req,
 					     1, DMA_TO_DEVICE);
-			if (n_elem_resp)
-				dma_unmap_sg(dev, &task->smp_task.smp_resp,
-					     1, DMA_FROM_DEVICE);
 		}
 	}
 }
 
 static int hisi_sas_dma_map(struct hisi_hba *hisi_hba,
 			    struct sas_task *task, int *n_elem,
-			    int *n_elem_req, int *n_elem_resp)
+			    int *n_elem_req)
 {
 	struct device *dev = hisi_hba->dev;
 	int rc;
@@ -331,7 +328,7 @@ static int hisi_sas_dma_map(struct hisi_hba *hisi_hba,
 	if (sas_protocol_ata(task->task_proto)) {
 		*n_elem = task->num_scatter;
 	} else {
-		unsigned int req_len, resp_len;
+		unsigned int req_len;
 
 		if (task->num_scatter) {
 			*n_elem = dma_map_sg(dev, task->scatter,
@@ -352,17 +349,6 @@ static int hisi_sas_dma_map(struct hisi_hba *hisi_hba,
 				rc = -EINVAL;
 				goto err_out_dma_unmap;
 			}
-			*n_elem_resp = dma_map_sg(dev, &task->smp_task.smp_resp,
-						  1, DMA_FROM_DEVICE);
-			if (!*n_elem_resp) {
-				rc = -ENOMEM;
-				goto err_out_dma_unmap;
-			}
-			resp_len = sg_dma_len(&task->smp_task.smp_resp);
-			if (resp_len & 0x3) {
-				rc = -EINVAL;
-				goto err_out_dma_unmap;
-			}
 		}
 	}
 
@@ -377,7 +363,7 @@ static int hisi_sas_dma_map(struct hisi_hba *hisi_hba,
 err_out_dma_unmap:
 	/* It would be better to call dma_unmap_sg() here, but it's messy */
 	hisi_sas_dma_unmap(hisi_hba, task, *n_elem,
-			   *n_elem_req, *n_elem_resp);
+			   *n_elem_req);
 prep_out:
 	return rc;
 }
@@ -449,7 +435,7 @@ static int hisi_sas_task_prep(struct sas_task *task,
 	struct asd_sas_port *sas_port = device->port;
 	struct device *dev = hisi_hba->dev;
 	int dlvry_queue_slot, dlvry_queue, rc, slot_idx;
-	int n_elem = 0, n_elem_dif = 0, n_elem_req = 0, n_elem_resp = 0;
+	int n_elem = 0, n_elem_dif = 0, n_elem_req = 0;
 	struct hisi_sas_dq *dq;
 	unsigned long flags;
 	int wr_q_index;
@@ -485,7 +471,7 @@ static int hisi_sas_task_prep(struct sas_task *task,
 	}
 
 	rc = hisi_sas_dma_map(hisi_hba, task, &n_elem,
-			      &n_elem_req, &n_elem_resp);
+			      &n_elem_req);
 	if (rc < 0)
 		goto prep_out;
 
@@ -580,7 +566,7 @@ err_out_dif_dma_unmap:
 		hisi_sas_dif_dma_unmap(hisi_hba, task, n_elem_dif);
 err_out_dma_unmap:
 	hisi_sas_dma_unmap(hisi_hba, task, n_elem,
-			   n_elem_req, n_elem_resp);
+			   n_elem_req);
 prep_out:
 	dev_err(dev, "task prep: failed[%d]!\n", rc);
 	return rc;