[RESEND PATCH V5 12/33] block: introduce bio_segments()

[Ming Lei]

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

Signed-off-by: Ming Lei <ming....@redhat.com>
---
 include/linux/bio.h | 25 ++++++++++++++++++++-----
 1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/include/linux/bio.h b/include/linux/bio.h
index 08af9272687f..b24c00f99c9c 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -227,9 +227,9 @@ static inline bool bio_rewind_iter(struct bio *bio, struct 
bvec_iter *iter,
 
 #define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len)
 
-static inline unsigned bio_pages(struct bio *bio)
+static inline unsigned __bio_elements(struct bio *bio, bool seg)
 {
-       unsigned segs = 0;
+       unsigned elems = 0;
        struct bio_vec bv;
        struct bvec_iter iter;
 
@@ -249,10 +249,25 @@ static inline unsigned bio_pages(struct bio *bio)
                break;
        }
 
-       bio_for_each_page(bv, bio, iter)
-               segs++;
+       if (!seg) {
+               bio_for_each_page(bv, bio, iter)
+                       elems++;
+       } else {
+               bio_for_each_segment(bv, bio, iter)
+                       elems++;
+       }
+
+       return elems;
+}
+
+static inline unsigned bio_pages(struct bio *bio)
+{
+       return __bio_elements(bio, false);
+}
 
-       return segs;
+static inline unsigned bio_segments(struct bio *bio)
+{
+       return __bio_elements(bio, true);
 }
 
 /*
-- 
2.9.5