Re: [PATCH v2 09/11] fuse: file: limit splice_read to virtiofs

From: Miklos Szeredi
Date: Wed Jan 10 2024 - 10:47:55 EST


On Wed, 10 Jan 2024 at 16:19, Ahelenia Ziemiańska
<nabijaczleweli@xxxxxxxxxxxxxxxxxx> wrote:

> > We need to find an alternative to refusing splice, since this is not
> > going to fly, IMO.
> The alternative is to not hold the lock. See the references in the
> cover letter for why this wasn't done. IMO a potential slight perf
> hit flies more than a total exclusion on the pipe.

IDGI. This will make splice(2) return EINVAL for unprivileged fuse
files, right?

That would be a regression, not a perf hit, if the application is not
falling back to plain read; a reasonable scenario, considering splice
from files (including fuse) has worked on linux for a *long* time.

Thanks,
Mikos