[PATCH V6 12/30] block: introduce bio_chunks()

Ming Lei
2018-06-09T12:33:05Z

There are still cases in which we need to use bio_chunks() for get the
number of multipage segment, so introduce it.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
include/linux/bio.h | 30 +++++++++++++++++++++++++-----
1 file changed, 25 insertions(+), 5 deletions(-)

diff --git a/include/linux/bio.h b/include/linux/bio.h
index c17b8f80d650..13fd7bc30390 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -242,7 +242,6 @@ static inline unsigned bio_segments(struct bio *bio)
* We special case discard/write same/write zeroes, because they
* interpret bi_size differently:
*/
-
switch (bio_op(bio)) {
case REQ_OP_DISCARD:
case REQ_OP_SECURE_ERASE:
@@ -251,13 +250,34 @@ static inline unsigned bio_segments(struct bio *bio)
case REQ_OP_WRITE_SAME:
return 1;
default:
- break;
+ bio_for_each_segment(bv, bio, iter)
+ segs++;
+ return segs;
}
+}

- bio_for_each_segment(bv, bio, iter)
- segs++;
+static inline unsigned bio_chunks(struct bio *bio)
+{
+ unsigned chunks = 0;
+ struct bio_vec bv;
+ struct bvec_iter iter;

- return segs;
+ /*
+ * We special case discard/write same/write zeroes, because they
+ * interpret bi_size differently:
+ */
+ switch (bio_op(bio)) {
+ case REQ_OP_DISCARD:
+ case REQ_OP_SECURE_ERASE:
+ case REQ_OP_WRITE_ZEROES:
+ return 0;
+ case REQ_OP_WRITE_SAME:
+ return 1;
+ default:
+ bio_for_each_chunk(bv, bio, iter)
+ chunks++;
+ return chunks;
+ }
}

/*
--
2.9.5