scsi: set ->scsi_done before calling scsi_dispatch_cmd

The blk-mq code path will set this to a different function, so make the
code simpler by setting it up in a legacy-request specific place.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Webb Scales <webbnh@hp.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Tested-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Robert Elliott <elliott@hp.com>
diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c
index 2396e89..6200a26 100644
--- a/drivers/scsi/scsi.c
+++ b/drivers/scsi/scsi.c
@@ -72,8 +72,6 @@
 #define CREATE_TRACE_POINTS
 #include <trace/events/scsi.h>
 
-static void scsi_done(struct scsi_cmnd *cmd);
-
 /*
  * Definitions and constants.
  */
@@ -693,8 +691,6 @@
 	}
 
 	trace_scsi_dispatch_cmd_start(cmd);
-
-	cmd->scsi_done = scsi_done;
 	rtn = host->hostt->queuecommand(host, cmd);
 	if (rtn) {
 		trace_scsi_dispatch_cmd_error(cmd, rtn);
@@ -708,28 +704,11 @@
 
 	return rtn;
  done:
-	scsi_done(cmd);
+	cmd->scsi_done(cmd);
 	return 0;
 }
 
 /**
- * scsi_done - Invoke completion on finished SCSI command.
- * @cmd: The SCSI Command for which a low-level device driver (LLDD) gives
- * ownership back to SCSI Core -- i.e. the LLDD has finished with it.
- *
- * Description: This function is the mid-level's (SCSI Core) interrupt routine,
- * which regains ownership of the SCSI command (de facto) from a LLDD, and
- * calls blk_complete_request() for further processing.
- *
- * This function is interrupt context safe.
- */
-static void scsi_done(struct scsi_cmnd *cmd)
-{
-	trace_scsi_dispatch_cmd_done(cmd);
-	blk_complete_request(cmd->request);
-}
-
-/**
  * scsi_finish_command - cleanup and pass command back to upper layer
  * @cmd: the command
  *