1 files changed, 10 insertions, 0 deletions
diff --git a/include/linux/bio.h b/include/linux/bio.h
index e135b500df5d..9ddb19801a03 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -10,6 +10,7 @@
 #include <linux/ioprio.h>
 /* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
 #include <linux/blk_types.h>
+#include <linux/uio.h>
 
 #define BIO_DEBUG
 
@@ -441,6 +442,15 @@ static inline void bio_wouldblock_error(struct bio *bio)
 	bio_endio(bio);
 }
 
+/*
+ * Calculate number of bvec segments that should be allocated to fit data
+ * pointed by @iter.
+ */
+static inline int bio_iov_vecs_to_alloc(struct iov_iter *iter, int max_segs)
+{
+	return iov_iter_npages(iter, max_segs);
+}
+
 struct request_queue;
 
 extern int submit_bio_wait(struct bio *bio);