[PATCH 3/7] block: Bring back zero_fill_bio_iter

[Kent Overstreet]

From: Kent Overstreet <kent.overstreet@xxxxxxxxx>

This reverts the commit that deleted it; it's used by bcachefs.

Signed-off-by: Kent Overstreet <kent.overstreet@xxxxxxxxx>
Cc: Jens Axboe <axboe@xxxxxxxxx>
Cc: linux-block@xxxxxxxxxxxxxxx
---
 block/bio.c         | 6 +++---
 include/linux/bio.h | 7 ++++++-
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/block/bio.c b/block/bio.c
index e74a04ea14..70b5c987bc 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -606,15 +606,15 @@ struct bio *bio_kmalloc(unsigned short nr_vecs, gfp_t gfp_mask)
 }
 EXPORT_SYMBOL(bio_kmalloc);
 
-void zero_fill_bio(struct bio *bio)
+void zero_fill_bio_iter(struct bio *bio, struct bvec_iter start)
 {
 	struct bio_vec bv;
 	struct bvec_iter iter;
 
-	bio_for_each_segment(bv, bio, iter)
+	__bio_for_each_segment(bv, bio, iter, start)
 		memzero_bvec(&bv);
 }
-EXPORT_SYMBOL(zero_fill_bio);
+EXPORT_SYMBOL(zero_fill_bio_iter);
 
 /**
  * bio_truncate - truncate the bio to small size of @new_size
diff --git a/include/linux/bio.h b/include/linux/bio.h
index d766be7152..3536f28c05 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -484,7 +484,12 @@ extern void bio_copy_data_iter(struct bio *dst, struct bvec_iter *dst_iter,
 extern void bio_copy_data(struct bio *dst, struct bio *src);
 extern void bio_free_pages(struct bio *bio);
 void guard_bio_eod(struct bio *bio);
-void zero_fill_bio(struct bio *bio);
+void zero_fill_bio_iter(struct bio *bio, struct bvec_iter iter);
+
+static inline void zero_fill_bio(struct bio *bio)
+{
+	zero_fill_bio_iter(bio, bio->bi_iter);
+}
 
 static inline void bio_release_pages(struct bio *bio, bool mark_dirty)
 {
-- 
2.40.1