block: move req_gap_{back,front}_merge to blk-merge.c

Keep it close to the actual users instead of exposing the function to all
drivers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/blk-merge.c b/block/blk-merge.c
index aaec38c..ad8a226 100644 (file)
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -12,6 +12,71 @@
 
 #include "blk.h"
 
+/*
+ * Check if the two bvecs from two bios can be merged to one segment.  If yes,
+ * no need to check gap between the two bios since the 1st bio and the 1st bvec
+ * in the 2nd bio can be handled in one segment.
+ */
+static inline bool bios_segs_mergeable(struct request_queue *q,
+               struct bio *prev, struct bio_vec *prev_last_bv,
+               struct bio_vec *next_first_bv)
+{
+       if (!BIOVEC_PHYS_MERGEABLE(prev_last_bv, next_first_bv))
+               return false;
+       if (!BIOVEC_SEG_BOUNDARY(q, prev_last_bv, next_first_bv))
+               return false;
+       if (prev->bi_seg_back_size + next_first_bv->bv_len >
+                       queue_max_segment_size(q))
+               return false;
+       return true;
+}
+
+static inline bool bio_will_gap(struct request_queue *q,
+               struct request *prev_rq, struct bio *prev, struct bio *next)
+{
+       struct bio_vec pb, nb;
+
+       if (!bio_has_data(prev) || !queue_virt_boundary(q))
+               return false;
+
+       /*
+        * Don't merge if the 1st bio starts with non-zero offset, otherwise it
+        * is quite difficult to respect the sg gap limit.  We work hard to
+        * merge a huge number of small single bios in case of mkfs.
+        */
+       if (prev_rq)
+               bio_get_first_bvec(prev_rq->bio, &pb);
+       else
+               bio_get_first_bvec(prev, &pb);
+       if (pb.bv_offset)
+               return true;
+
+       /*
+        * We don't need to worry about the situation that the merged segment
+        * ends in unaligned virt boundary:
+        *
+        * - if 'pb' ends aligned, the merged segment ends aligned
+        * - if 'pb' ends unaligned, the next bio must include
+        *   one single bvec of 'nb', otherwise the 'nb' can't
+        *   merge with 'pb'
+        */
+       bio_get_last_bvec(prev, &pb);
+       bio_get_first_bvec(next, &nb);
+       if (bios_segs_mergeable(q, prev, &pb, &nb))
+               return false;
+       return __bvec_gap_to_prev(q, &pb, nb.bv_offset);
+}
+
+static inline bool req_gap_back_merge(struct request *req, struct bio *bio)
+{
+       return bio_will_gap(req->q, req, req->biotail, bio);
+}
+
+static inline bool req_gap_front_merge(struct request *req, struct bio *bio)
+{
+       return bio_will_gap(req->q, NULL, bio, req->bio);
+}
+
 static struct bio *blk_bio_discard_split(struct request_queue *q,
                                         struct bio *bio,
                                         struct bio_set *bs,

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index bc534c8..b7e676b 100644 (file)
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1695,75 +1695,6 @@ static inline bool bvec_gap_to_prev(struct request_queue *q,
        return __bvec_gap_to_prev(q, bprv, offset);
 }
 
-/*
- * Check if the two bvecs from two bios can be merged to one segment.
- * If yes, no need to check gap between the two bios since the 1st bio
- * and the 1st bvec in the 2nd bio can be handled in one segment.
- */
-static inline bool bios_segs_mergeable(struct request_queue *q,
-               struct bio *prev, struct bio_vec *prev_last_bv,
-               struct bio_vec *next_first_bv)
-{
-       if (!BIOVEC_PHYS_MERGEABLE(prev_last_bv, next_first_bv))
-               return false;
-       if (!BIOVEC_SEG_BOUNDARY(q, prev_last_bv, next_first_bv))
-               return false;
-       if (prev->bi_seg_back_size + next_first_bv->bv_len >
-                       queue_max_segment_size(q))
-               return false;
-       return true;
-}
-
-static inline bool bio_will_gap(struct request_queue *q,
-                               struct request *prev_rq,
-                               struct bio *prev,
-                               struct bio *next)
-{
-       if (bio_has_data(prev) && queue_virt_boundary(q)) {
-               struct bio_vec pb, nb;
-
-               /*
-                * don't merge if the 1st bio starts with non-zero
-                * offset, otherwise it is quite difficult to respect
-                * sg gap limit. We work hard to merge a huge number of small
-                * single bios in case of mkfs.
-                */
-               if (prev_rq)
-                       bio_get_first_bvec(prev_rq->bio, &pb);
-               else
-                       bio_get_first_bvec(prev, &pb);
-               if (pb.bv_offset)
-                       return true;
-
-               /*
-                * We don't need to worry about the situation that the
-                * merged segment ends in unaligned virt boundary:
-                *
-                * - if 'pb' ends aligned, the merged segment ends aligned
-                * - if 'pb' ends unaligned, the next bio must include
-                *   one single bvec of 'nb', otherwise the 'nb' can't
-                *   merge with 'pb'
-                */
-               bio_get_last_bvec(prev, &pb);
-               bio_get_first_bvec(next, &nb);
-
-               if (!bios_segs_mergeable(q, prev, &pb, &nb))
-                       return __bvec_gap_to_prev(q, &pb, nb.bv_offset);
-       }
-
-       return false;
-}
-
-static inline bool req_gap_back_merge(struct request *req, struct bio *bio)
-{
-       return bio_will_gap(req->q, req, req->biotail, bio);
-}
-
-static inline bool req_gap_front_merge(struct request *req, struct bio *bio)
-{
-       return bio_will_gap(req->q, NULL, bio, req->bio);
-}
-
 int kblockd_schedule_work(struct work_struct *work);
 int kblockd_schedule_work_on(int cpu, struct work_struct *work);
 int kblockd_mod_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);