Update to 3.4-final.

[linux-flexiantxendom0-3.2.10.git] / block / blk-merge.c

diff --git a/block/blk-merge.c b/block/blk-merge.c
index 74bc4a7..160035f 100644 (file)
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -351,11 +351,12 @@ static void blk_account_io_merge(struct request *req)
                int cpu;
 
                cpu = part_stat_lock();
-               part = disk_map_sector_rcu(req->rq_disk, blk_rq_pos(req));
+               part = req->part;
 
                part_round_stats(cpu, part);
                part_dec_in_flight(part, rq_data_dir(req));
 
+               hd_struct_put(part);
                part_stat_unlock();
        }
 }
@@ -464,3 +465,46 @@ int attempt_front_merge(struct request_queue *q, struct request *rq)
 
        return 0;
 }
+
+int blk_attempt_req_merge(struct request_queue *q, struct request *rq,
+                         struct request *next)
+{
+       return attempt_merge(q, rq, next);
+}
+
+bool blk_rq_merge_ok(struct request *rq, struct bio *bio)
+{
+       if (!rq_mergeable(rq))
+               return false;
+
+       /* don't merge file system requests and discard requests */
+       if ((bio->bi_rw & REQ_DISCARD) != (rq->bio->bi_rw & REQ_DISCARD))
+               return false;
+
+       /* don't merge discard requests and secure discard requests */
+       if ((bio->bi_rw & REQ_SECURE) != (rq->bio->bi_rw & REQ_SECURE))
+               return false;
+
+       /* different data direction or already started, don't merge */
+       if (bio_data_dir(bio) != rq_data_dir(rq))
+               return false;
+
+       /* must be same device and not a special request */
+       if (rq->rq_disk != bio->bi_bdev->bd_disk || rq->special)
+               return false;
+
+       /* only merge integrity protected bio into ditto rq */
+       if (bio_integrity(bio) != blk_integrity_rq(rq))
+               return false;
+
+       return true;
+}
+
+int blk_try_merge(struct request *rq, struct bio *bio)
+{
+       if (blk_rq_pos(rq) + blk_rq_sectors(rq) == bio->bi_sector)
+               return ELEVATOR_BACK_MERGE;
+       else if (blk_rq_pos(rq) - bio_sectors(bio) == bio->bi_sector)
+               return ELEVATOR_FRONT_MERGE;
+       return ELEVATOR_NO_MERGE;
+}