block: simplify blk_recalc_rq_segments

Return the segement and let the callers assign them, which makes the code
a littler more obvious.  Also pass the request instead of q plus bio
chain, allowing for the use of rq_for_each_bvec.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 6 insertions, 15 deletions

diff --git a/block/blk-merge.c b/block/blk-merge.c
index 72b4fd89a22d..2ea21ffd5f72 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -310,17 +310,16 @@ void blk_queue_split(struct request_queue *q, struct bio **bio)
 }
 EXPORT_SYMBOL(blk_queue_split);
 
-static unsigned int __blk_recalc_rq_segments(struct request_queue *q,
-                                             struct bio *bio)
+unsigned int blk_recalc_rq_segments(struct request *rq)
 {
         unsigned int nr_phys_segs = 0;
-        struct bvec_iter iter;
+        struct req_iterator iter;
         struct bio_vec bv;
 
-        if (!bio)
+        if (!rq->bio)
                 return 0;
 
-        switch (bio_op(bio)) {
+        switch (bio_op(rq->bio)) {
         case REQ_OP_DISCARD:
         case REQ_OP_SECURE_ERASE:
         case REQ_OP_WRITE_ZEROES:
@@ -329,19 +328,11 @@ static unsigned int __blk_recalc_rq_segments(struct request_queue *q,
                 return 1;
         }
 
-        for_each_bio(bio) {
-                bio_for_each_bvec(bv, bio, iter)
-                        bvec_split_segs(q, &bv, &nr_phys_segs, NULL, UINT_MAX);
-        }
-
+        rq_for_each_bvec(bv, rq, iter)
+                bvec_split_segs(rq->q, &bv, &nr_phys_segs, NULL, UINT_MAX);
         return nr_phys_segs;
 }
 
-void blk_recalc_rq_segments(struct request *rq)
-{
-        rq->nr_phys_segments = __blk_recalc_rq_segments(rq->q, rq->bio);
-}
-
 static inline struct scatterlist *blk_next_sg(struct scatterlist **sg,
                 struct scatterlist *sglist)
 {