Re: [PATCH 08/43] xfs: report the correct dio alignment for COW inodes

Christoph Hellwig
2024-12-13T05:09:17Z

On Thu, Dec 12, 2024 at 01:29:53PM -0800, Darrick J. Wong wrote:
> > + /*
> > + * On COW inodes we are forced to always rewrite an entire file system
> > + * block.
>
> That's not quite accurate -- we're always forced to write an entire file
> allocation unit so that the rest of the bmap code doesn't have to deal
> with a file range that's mapped to multiple different space extents.
> For all the existing reflink scenarios the allocation unit is always an
> fsblock so this is a trifling difference.

Which right now is a block until we support horrors such as reflink
on larget rtextsize inodes or the forcealign stuff. But yes, it
could use the helper.