[PATCH v6 05/28] block: Allow using bio_attempt_back_merge() internally

[Damien Le Moal <dlemoal@kernel.org>]

Remove "static" from the definition of bio_attempt_back_merge() and
declare this function in block/blk.h to allow using it internally from
other block layer files. The definition of enum bio_merge_status is
also moved to block/blk.h.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Hans Holmberg <hans.holmberg@wdc.com>
---
 block/blk-merge.c | 8 +-------
 block/blk.h       | 8 ++++++++
 2 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/block/blk-merge.c b/block/blk-merge.c
index 4e3483a16b75..3363b1321908 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -972,13 +972,7 @@ static void blk_account_io_merge_bio(struct request *req)
 	part_stat_unlock();
 }
 
-enum bio_merge_status {
-	BIO_MERGE_OK,
-	BIO_MERGE_NONE,
-	BIO_MERGE_FAILED,
-};
-
-static enum bio_merge_status bio_attempt_back_merge(struct request *req,
+enum bio_merge_status bio_attempt_back_merge(struct request *req,
 		struct bio *bio, unsigned int nr_segs)
 {
 	const blk_opf_t ff = bio_failfast(bio);
diff --git a/block/blk.h b/block/blk.h
index 17786052f32d..bca50a9510c8 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -269,6 +269,14 @@ static inline void bio_integrity_free(struct bio *bio)
 unsigned long blk_rq_timeout(unsigned long timeout);
 void blk_add_timer(struct request *req);
 
+enum bio_merge_status {
+	BIO_MERGE_OK,
+	BIO_MERGE_NONE,
+	BIO_MERGE_FAILED,
+};
+
+enum bio_merge_status bio_attempt_back_merge(struct request *req,
+		struct bio *bio, unsigned int nr_segs);
 bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio,
 		unsigned int nr_segs);
 bool blk_bio_list_merge(struct request_queue *q, struct list_head *list,
-- 
2.44.0