Re: [RFC PATCH 1/2] fs: introduce FALLOC_FL_FORCE_ZERO to fallocate

[Christoph Hellwig]

On Mon, Jan 06, 2025 at 09:31:33AM -0800, Darrick J. Wong wrote:
> I think we should wire it up as a new FALLOC_FL_WRITE_ZEROES mode,
> document very vigorously that it exists to facilitate pure overwrites
> (specifically that it returns EOPNOTSUPP for always-cow files), and not
> add more ioctls.

That goes into a similar direction to what I'd prefer.

> (That said, doesn't BLKZEROOUT already do this for bdevs?)

Yes. But the same is true for the other fallocate modes on block
devices.