btrfs: separate types for submit_bio_start and submit_bio_done

The callbacks make use of different parameters that are passed to the
other type unnecessarily. This patch adds separate types for each and
the unused parameters will be removed.

The type extent_submit_bio_hook_t keeps all parameters and can be used
where the start/done types are not appropriate.
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/disk-io.c

@@ -124,8 +124,8 @@ struct async_submit_bio {
 	void *private_data;
 	struct btrfs_fs_info *fs_info;
 	struct bio *bio;
-	extent_submit_bio_hook_t *submit_bio_start;
-	extent_submit_bio_hook_t *submit_bio_done;
+	extent_submit_bio_start_t *submit_bio_start;
+	extent_submit_bio_done_t *submit_bio_done;
 	int mirror_num;
 	unsigned long bio_flags;
 	/*
@@ -751,8 +751,8 @@ static void run_one_async_free(struct btrfs_work *work)
 blk_status_t btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
 				 int mirror_num, unsigned long bio_flags,
 				 u64 bio_offset, void *private_data,
-				 extent_submit_bio_hook_t *submit_bio_start,
-				 extent_submit_bio_hook_t *submit_bio_done)
+				 extent_submit_bio_start_t *submit_bio_start,
+				 extent_submit_bio_done_t *submit_bio_done)
 {
 	struct async_submit_bio *async;
 

fs/btrfs/disk-io.h

@@ -131,8 +131,8 @@ blk_status_t btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
 blk_status_t btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
 			int mirror_num, unsigned long bio_flags,
 			u64 bio_offset, void *private_data,
-			extent_submit_bio_hook_t *submit_bio_start,
-			extent_submit_bio_hook_t *submit_bio_done);
+			extent_submit_bio_start_t *submit_bio_start,
+			extent_submit_bio_done_t *submit_bio_done);
 int btrfs_write_tree_block(struct extent_buffer *buf);
 void btrfs_wait_tree_block_writeback(struct extent_buffer *buf);
 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,

fs/btrfs/extent_io.h

@@ -95,6 +95,15 @@ struct io_failure_record;
 typedef	blk_status_t (extent_submit_bio_hook_t)(void *private_data, struct bio *bio,
 				       int mirror_num, unsigned long bio_flags,
 				       u64 bio_offset);
+
+typedef blk_status_t (extent_submit_bio_start_t)(void *private_data,
+		struct bio *bio, int mirror_num, unsigned long bio_flags,
+		u64 bio_offset);
+
+typedef blk_status_t (extent_submit_bio_done_t)(void *private_data,
+		struct bio *bio, int mirror_num, unsigned long bio_flags,
+		u64 bio_offset);
+
 struct extent_io_ops {
 	/*
 	 * The following callbacks must be allways defined, the function