Re: [RFC PATCH 2/2] mm: introduce budgt control in readahead

[Christoph Hellwig]

> +	unsigned long budgt = inode->i_sb->s_bdev ?
> +			blk_throttle_budgt(inode->i_sb->s_bdev) : 0;

The readahead code is used for all file systems, you can't just call
into block layer code here.