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authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2012-03-09 12:35:53 -0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2012-03-09 12:35:53 -0800
commit263a5c8e16c34199ddf6de3f102e789ffa3ee26e (patch)
tree4f049e339d522b2ab0ba3bed3ec217e4bbc83d35 /block/blk-merge.c
parent54d20f006ceff1f2f1e69d0e54049b6c0765c039 (diff)
parent192cfd58774b4d17b2fe8bdc77d89c2ef4e0591d (diff)
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Merge 3.3-rc6 into driver-core-next
This was done to resolve a conflict in the drivers/base/cpu.c file. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'block/blk-merge.c')
-rw-r--r--block/blk-merge.c37
1 files changed, 37 insertions, 0 deletions
diff --git a/block/blk-merge.c b/block/blk-merge.c
index cfcc37cb222b..160035f54882 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -471,3 +471,40 @@ int blk_attempt_req_merge(struct request_queue *q, struct request *rq,
{
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;
+}