btrfs: merge two superblock writing helpers

write_all_supers and write_ctree_super are almost equal, the parameter
'trans' is unused so we can drop it and have just one helper.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/disk-io.c

@@ -3695,7 +3695,7 @@ int btrfs_calc_num_tolerated_disk_barrier_failures(
 	return num_tolerated_disk_barrier_failures;
 }
 
-static int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors)
+int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors)
 {
 	struct list_head *head;
 	struct btrfs_device *dev;
@@ -3789,12 +3789,6 @@ static int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors)
 	return 0;
 }
 
-int write_ctree_super(struct btrfs_trans_handle *trans,
-		      struct btrfs_fs_info *fs_info, int max_mirrors)
-{
-	return write_all_supers(fs_info, max_mirrors);
-}
-
 /* Drop a fs root from the radix tree and free it. */
 void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
 				  struct btrfs_root *root)

fs/btrfs/disk-io.h

@@ -57,8 +57,7 @@ int open_ctree(struct super_block *sb,
 	       struct btrfs_fs_devices *fs_devices,
 	       char *options);
 void close_ctree(struct btrfs_fs_info *fs_info);
-int write_ctree_super(struct btrfs_trans_handle *trans,
-		      struct btrfs_fs_info *fs_info, int max_mirrors);
+int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors);
 struct buffer_head *btrfs_read_dev_super(struct block_device *bdev);
 int btrfs_read_dev_one_super(struct block_device *bdev, int copy_num,
 			struct buffer_head **bh_ret);

fs/btrfs/transaction.c

@@ -2257,7 +2257,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans)
 		goto scrub_continue;
 	}
 
-	ret = write_ctree_super(trans, fs_info, 0);
+	ret = write_all_supers(fs_info, 0);
 	if (ret) {
 		mutex_unlock(&fs_info->tree_log_mutex);
 		goto scrub_continue;

fs/btrfs/tree-log.c

@@ -2961,7 +2961,7 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 	 * the running transaction open, so a full commit can't hop
 	 * in and cause problems either.
 	 */
-	ret = write_ctree_super(trans, fs_info, 1);
+	ret = write_all_supers(fs_info, 1);
 	if (ret) {
 		btrfs_set_log_full_commit(fs_info, trans);
 		btrfs_abort_transaction(trans, ret);