[SCSI] Get rid of scsi_cmnd->done

The ULD ->done callback moves into the scsi_driver.  By moving the call
to scsi_io_completion() from scsi_blk_pc_done() to scsi_finish_command(),
we can eliminate the latter entirely.  By returning 'good_bytes' from
the ->done callback (rather than invoking scsi_io_completion()), we can
stop exporting scsi_io_completion().

Also move the prototypes from sd.h to sd.c as they're all internal anyway.
Rename sd_rw_intr to sd_done and rw_intr to sr_done.

Inspired-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
index a0c4e13..c619990 100644
--- a/drivers/scsi/sr.c
+++ b/drivers/scsi/sr.c
@@ -78,6 +78,7 @@
 
 static int sr_probe(struct device *);
 static int sr_remove(struct device *);
+static int sr_done(struct scsi_cmnd *);
 
 static struct scsi_driver sr_template = {
 	.owner			= THIS_MODULE,
@@ -86,6 +87,7 @@
 		.probe		= sr_probe,
 		.remove		= sr_remove,
 	},
+	.done			= sr_done,
 };
 
 static unsigned long sr_index_bits[SR_DISKS / BITS_PER_LONG];
@@ -208,12 +210,12 @@
 }
  
 /*
- * rw_intr is the interrupt routine for the device driver.
+ * sr_done is the interrupt routine for the device driver.
  *
- * It will be notified on the end of a SCSI read / write, and will take on
+ * It will be notified on the end of a SCSI read / write, and will take one
  * of several actions based on success or failure.
  */
-static void rw_intr(struct scsi_cmnd * SCpnt)
+static int sr_done(struct scsi_cmnd *SCpnt)
 {
 	int result = SCpnt->result;
 	int this_count = SCpnt->request_bufflen;
@@ -286,12 +288,7 @@
 		}
 	}
 
-	/*
-	 * This calls the generic completion function, now that we know
-	 * how many actual sectors finished, and how many sectors we need
-	 * to say have failed.
-	 */
-	scsi_io_completion(SCpnt, good_bytes);
+	return good_bytes;
 }
 
 static int sr_prep_fn(struct request_queue *q, struct request *rq)
@@ -428,12 +425,6 @@
 	SCpnt->timeout_per_command = timeout;
 
 	/*
-	 * This is the completion routine we use.  This is matched in terms
-	 * of capability to this function.
-	 */
-	SCpnt->done = rw_intr;
-
-	/*
 	 * This indicates that the command is ready from our end to be
 	 * queued.
 	 */