Re: [RFC PATCH 01/11] vfs: push __sync_blockdev calls down into sync_fs routines

From: Christoph Hellwig
Date: Fri May 18 2018 - 11:00:29 EST


> --- a/fs/xfs/xfs_super.c
> +++ b/fs/xfs/xfs_super.c
> @@ -1097,7 +1097,7 @@ xfs_fs_sync_fs(
> * Doing anything during the async pass would be counterproductive.
> */
> if (!wait)
> - return 0;
> + goto out;
>
> xfs_log_force(mp, XFS_LOG_SYNC);
> if (laptop_mode) {
> @@ -1108,8 +1108,8 @@ xfs_fs_sync_fs(
> */
> flush_delayed_work(&mp->m_log->l_work);
> }
> -
> - return 0;
> +out:
> + return __sync_blockdev(sb->s_bdev, wait);

XFS never uses the block device mapping for anything, so this is
not needed.

> +/*
> + * Many legacy filesystems don't have a sync_fs op. For them, we just flush
> + * the block device (if there is one).
> + */
> +static inline int call_sync_fs(struct super_block *sb, int wait)
> +{
> + if (sb->s_op->sync_fs)
> + return sb->s_op->sync_fs(sb, wait);
> + return __sync_blockdev(sb->s_bdev, wait);
> +}

The proper name for this would be vfs_sync_fs. And I don't think it
warrants an inline.