blk_end_request: changing nbd (take 4)

This patch converts nbd to use blk_end_request interfaces.
Related 'uptodate' arguments are converted to 'error'.

Cc: Paul Clements <Paul.Clements@steeleye.com>
Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

drivers/block/nbd.c

@@ -100,17 +100,15 @@ static const char *nbdcmd_to_ascii(int cmd)
 
 static void nbd_end_request(struct request *req)
 {
-	int uptodate = (req->errors == 0) ? 1 : 0;
+	int error = req->errors ? -EIO : 0;
 	struct request_queue *q = req->q;
 	unsigned long flags;
 
 	dprintk(DBG_BLKDEV, "%s: request %p: %s\n", req->rq_disk->disk_name,
-			req, uptodate? "done": "failed");
+			req, error ? "failed" : "done");
 
 	spin_lock_irqsave(q->queue_lock, flags);
-	if (!end_that_request_first(req, uptodate, req->nr_sectors)) {
-		end_that_request_last(req, uptodate);
-	}
+	__blk_end_request(req, error, req->nr_sectors << 9);
 	spin_unlock_irqrestore(q->queue_lock, flags);
 }