block: reorder request completion functions

[~andy/linux] / block / blk-core.c

diff --git a/block/blk-core.c b/block/blk-core.c
index 8b4a0af7d69fe92175ef7ecf27d05edd66e87c39..406a93e526b633fee6c9ea4dfc3865cb67f3daf9 100644 (file)
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -946,7 +946,6 @@ void blk_insert_request(struct request_queue *q, struct request *rq,
         * barrier
         */
        rq->cmd_type = REQ_TYPE_SPECIAL;
-       rq->cmd_flags |= REQ_SOFTBARRIER;
 
        rq->special = data;
 
@@ -1082,16 +1081,13 @@ void init_request_from_bio(struct request *req, struct bio *bio)
        if (bio_failfast_driver(bio))
                req->cmd_flags |= REQ_FAILFAST_DRIVER;
 
-       /*
-        * REQ_BARRIER implies no merging, but lets make it explicit
-        */
        if (unlikely(bio_discard(bio))) {
                req->cmd_flags |= REQ_DISCARD;
                if (bio_barrier(bio))
                        req->cmd_flags |= REQ_SOFTBARRIER;
                req->q->prepare_discard_fn(req->q, req);
        } else if (unlikely(bio_barrier(bio)))
-               req->cmd_flags |= (REQ_HARDBARRIER | REQ_NOMERGE);
+               req->cmd_flags |= REQ_HARDBARRIER;
 
        if (bio_sync(bio))
                req->cmd_flags |= REQ_RW_SYNC;
@@ -1687,6 +1683,35 @@ static void blk_account_io_done(struct request *req)
        }
 }
 
+/**
+ * blk_rq_bytes - Returns bytes left to complete in the entire request
+ * @rq: the request being processed
+ **/
+unsigned int blk_rq_bytes(struct request *rq)
+{
+       if (blk_fs_request(rq))
+               return rq->hard_nr_sectors << 9;
+
+       return rq->data_len;
+}
+EXPORT_SYMBOL_GPL(blk_rq_bytes);
+
+/**
+ * blk_rq_cur_bytes - Returns bytes left to complete in the current segment
+ * @rq: the request being processed
+ **/
+unsigned int blk_rq_cur_bytes(struct request *rq)
+{
+       if (blk_fs_request(rq))
+               return rq->current_nr_sectors << 9;
+
+       if (rq->bio)
+               return rq->bio->bi_size;
+
+       return rq->data_len;
+}
+EXPORT_SYMBOL_GPL(blk_rq_cur_bytes);
+
 /**
  * __end_that_request_first - end I/O on a request
  * @req:      the request being processed
@@ -1801,6 +1826,22 @@ static int __end_that_request_first(struct request *req, int error,
        return 1;
 }
 
+static int end_that_request_data(struct request *rq, int error,
+                                unsigned int nr_bytes, unsigned int bidi_bytes)
+{
+       if (rq->bio) {
+               if (__end_that_request_first(rq, error, nr_bytes))
+                       return 1;
+
+               /* Bidi request must be completed as a whole */
+               if (blk_bidi_rq(rq) &&
+                   __end_that_request_first(rq->next_rq, error, bidi_bytes))
+                       return 1;
+       }
+
+       return 0;
+}
+
 /*
  * queue lock must be held
  */
@@ -1829,78 +1870,6 @@ static void end_that_request_last(struct request *req, int error)
        }
 }
 
-/**
- * blk_rq_bytes - Returns bytes left to complete in the entire request
- * @rq: the request being processed
- **/
-unsigned int blk_rq_bytes(struct request *rq)
-{
-       if (blk_fs_request(rq))
-               return rq->hard_nr_sectors << 9;
-
-       return rq->data_len;
-}
-EXPORT_SYMBOL_GPL(blk_rq_bytes);
-
-/**
- * blk_rq_cur_bytes - Returns bytes left to complete in the current segment
- * @rq: the request being processed
- **/
-unsigned int blk_rq_cur_bytes(struct request *rq)
-{
-       if (blk_fs_request(rq))
-               return rq->current_nr_sectors << 9;
-
-       if (rq->bio)
-               return rq->bio->bi_size;
-
-       return rq->data_len;
-}
-EXPORT_SYMBOL_GPL(blk_rq_cur_bytes);
-
-/**
- * end_request - end I/O on the current segment of the request
- * @req:       the request being processed
- * @uptodate:  error value or %0/%1 uptodate flag
- *
- * Description:
- *     Ends I/O on the current segment of a request. If that is the only
- *     remaining segment, the request is also completed and freed.
- *
- *     This is a remnant of how older block drivers handled I/O completions.
- *     Modern drivers typically end I/O on the full request in one go, unless
- *     they have a residual value to account for. For that case this function
- *     isn't really useful, unless the residual just happens to be the
- *     full current segment. In other words, don't use this function in new
- *     code. Use blk_end_request() or __blk_end_request() to end a request.
- **/
-void end_request(struct request *req, int uptodate)
-{
-       int error = 0;
-
-       if (uptodate <= 0)
-               error = uptodate ? uptodate : -EIO;
-
-       __blk_end_request(req, error, req->hard_cur_sectors << 9);
-}
-EXPORT_SYMBOL(end_request);
-
-static int end_that_request_data(struct request *rq, int error,
-                                unsigned int nr_bytes, unsigned int bidi_bytes)
-{
-       if (rq->bio) {
-               if (__end_that_request_first(rq, error, nr_bytes))
-                       return 1;
-
-               /* Bidi request must be completed as a whole */
-               if (blk_bidi_rq(rq) &&
-                   __end_that_request_first(rq->next_rq, error, bidi_bytes))
-                       return 1;
-       }
-
-       return 0;
-}
-
 /**
  * blk_end_io - Generic end_io function to complete a request.
  * @rq:           the request being processed
@@ -2010,6 +1979,33 @@ int blk_end_bidi_request(struct request *rq, int error, unsigned int nr_bytes,
 }
 EXPORT_SYMBOL_GPL(blk_end_bidi_request);
 
+/**
+ * end_request - end I/O on the current segment of the request
+ * @req:       the request being processed
+ * @uptodate:  error value or %0/%1 uptodate flag
+ *
+ * Description:
+ *     Ends I/O on the current segment of a request. If that is the only
+ *     remaining segment, the request is also completed and freed.
+ *
+ *     This is a remnant of how older block drivers handled I/O completions.
+ *     Modern drivers typically end I/O on the full request in one go, unless
+ *     they have a residual value to account for. For that case this function
+ *     isn't really useful, unless the residual just happens to be the
+ *     full current segment. In other words, don't use this function in new
+ *     code. Use blk_end_request() or __blk_end_request() to end a request.
+ **/
+void end_request(struct request *req, int uptodate)
+{
+       int error = 0;
+
+       if (uptodate <= 0)
+               error = uptodate ? uptodate : -EIO;
+
+       __blk_end_request(req, error, req->hard_cur_sectors << 9);
+}
+EXPORT_SYMBOL(end_request);
+
 /**
  * blk_update_request - Special helper function for request stacking drivers
  * @rq:           the request being processed