blk_end_request: changing block layer core (take 4)

This patch converts core parts of block layer to use blk_end_request
interfaces.  Related 'uptodate' arguments are converted to 'error'.

'dequeue' argument was originally introduced for end_dequeued_request(),
where no attempt should be made to dequeue the request as it's already
dequeued.
However, it's not necessary as it can be checked with
list_empty(&rq->queuelist).
(Dequeued request has empty list and queued request doesn't.)
And it has been done in blk_end_request interfaces.

As a result of this patch, end_queued_request() and
end_dequeued_request() become identical.  A future patch will merge
and rename them and change users of those functions.

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>

diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c
index 8b2b2509f60e691094a6d0cc91bdb0772b30acd2..fb951198c70e7d1cf423f6051c4d79617e3f35ec 100644 (file)
--- a/block/ll_rw_blk.c
+++ b/block/ll_rw_blk.c
@@ -347,7 +347,6 @@ unsigned blk_ordered_req_seq(struct request *rq)
 void blk_ordered_complete_seq(struct request_queue *q, unsigned seq, int error)
 {
        struct request *rq;
-       int uptodate;
 
        if (error && !q->orderr)
                q->orderr = error;
@@ -361,15 +360,11 @@ void blk_ordered_complete_seq(struct request_queue *q, unsigned seq, int error)
        /*
         * Okay, sequence complete.
         */
-       uptodate = 1;
-       if (q->orderr)
-               uptodate = q->orderr;
-
        q->ordseq = 0;
        rq = q->orig_bar_rq;
 
-       end_that_request_first(rq, uptodate, rq->hard_nr_sectors);
-       end_that_request_last(rq, uptodate);
+       if (__blk_end_request(rq, q->orderr, blk_rq_bytes(rq)))
+               BUG();
 }
 
 static void pre_flush_end_io(struct request *rq, int error)
@@ -486,9 +481,9 @@ int blk_do_ordered(struct request_queue *q, struct request **rqp)
                         * ORDERED_NONE while this request is on it.
                         */
                        blkdev_dequeue_request(rq);
-                       end_that_request_first(rq, -EOPNOTSUPP,
-                                              rq->hard_nr_sectors);
-                       end_that_request_last(rq, -EOPNOTSUPP);
+                       if (__blk_end_request(rq, -EOPNOTSUPP,
+                                             blk_rq_bytes(rq)))
+                               BUG();
                        *rqp = NULL;
                        return 0;
                }
@@ -3713,14 +3708,14 @@ void end_that_request_last(struct request *req, int uptodate)
 EXPORT_SYMBOL(end_that_request_last);
 
 static inline void __end_request(struct request *rq, int uptodate,
-                                unsigned int nr_bytes, int dequeue)
+                                unsigned int nr_bytes)
 {
-       if (!end_that_request_chunk(rq, uptodate, nr_bytes)) {
-               if (dequeue)
-                       blkdev_dequeue_request(rq);
-               add_disk_randomness(rq->rq_disk);
-               end_that_request_last(rq, uptodate);
-       }
+       int error = 0;
+
+       if (uptodate <= 0)
+               error = uptodate ? uptodate : -EIO;
+
+       __blk_end_request(rq, error, nr_bytes);
 }
 
 /**
@@ -3763,7 +3758,7 @@ EXPORT_SYMBOL_GPL(blk_rq_cur_bytes);
  **/
 void end_queued_request(struct request *rq, int uptodate)
 {
-       __end_request(rq, uptodate, blk_rq_bytes(rq), 1);
+       __end_request(rq, uptodate, blk_rq_bytes(rq));
 }
 EXPORT_SYMBOL(end_queued_request);
 
@@ -3780,7 +3775,7 @@ EXPORT_SYMBOL(end_queued_request);
  **/
 void end_dequeued_request(struct request *rq, int uptodate)
 {
-       __end_request(rq, uptodate, blk_rq_bytes(rq), 0);
+       __end_request(rq, uptodate, blk_rq_bytes(rq));
 }
 EXPORT_SYMBOL(end_dequeued_request);
 
@@ -3806,7 +3801,7 @@ EXPORT_SYMBOL(end_dequeued_request);
  **/
 void end_request(struct request *req, int uptodate)
 {
-       __end_request(req, uptodate, req->hard_cur_sectors << 9, 1);
+       __end_request(req, uptodate, req->hard_cur_sectors << 9);
 }
 EXPORT_SYMBOL(end_request);