scsi: add scsi_setup_cmnd helper

Factor out command setup code that will be shared with the blk-mq code path.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Webb Scales <webbnh@hp.com>

1 files changed, 22 insertions, 18 deletions

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 85cf0ef843f6..04c368470c8a 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1092,6 +1092,27 @@ static int scsi_setup_fs_cmnd(struct scsi_device *sdev, struct request *req)
         return scsi_cmd_to_driver(cmd)->init_command(cmd);
 }
 
+static int scsi_setup_cmnd(struct scsi_device *sdev, struct request *req)
+{
+        struct scsi_cmnd *cmd = req->special;
+
+        if (!blk_rq_bytes(req))
+                cmd->sc_data_direction = DMA_NONE;
+        else if (rq_data_dir(req) == WRITE)
+                cmd->sc_data_direction = DMA_TO_DEVICE;
+        else
+                cmd->sc_data_direction = DMA_FROM_DEVICE;
+
+        switch (req->cmd_type) {
+        case REQ_TYPE_FS:
+                return scsi_setup_fs_cmnd(sdev, req);
+        case REQ_TYPE_BLOCK_PC:
+                return scsi_setup_blk_pc_cmnd(sdev, req);
+        default:
+                return BLKPREP_KILL;
+        }
+}
+
 static int
 scsi_prep_state_check(struct scsi_device *sdev, struct request *req)
 {
@@ -1195,24 +1216,7 @@ static int scsi_prep_fn(struct request_queue *q, struct request *req)
                 goto out;
         }
 
-        if (!blk_rq_bytes(req))
-                cmd->sc_data_direction = DMA_NONE;
-        else if (rq_data_dir(req) == WRITE)
-                cmd->sc_data_direction = DMA_TO_DEVICE;
-        else
-                cmd->sc_data_direction = DMA_FROM_DEVICE;
-
-        switch (req->cmd_type) {
-        case REQ_TYPE_FS:
-                ret = scsi_setup_fs_cmnd(sdev, req);
-                break;
-        case REQ_TYPE_BLOCK_PC:
-                ret = scsi_setup_blk_pc_cmnd(sdev, req);
-                break;
-        default:
-                ret = BLKPREP_KILL;
-        }
-
+        ret = scsi_setup_cmnd(sdev, req);
 out:
         return scsi_prep_return(q, req, ret);
 }