Re: [PATCH RFC 18/20] fs: add f_pipe

[Christian Brauner <brauner@kernel.org>]

On Tue, Sep 03, 2024 at 03:50:55PM GMT, Jan Kara wrote:
> On Fri 30-08-24 15:04:59, Christian Brauner wrote:
> > Only regular files with FMODE_ATOMIC_POS and directories need
> > f_pos_lock. Place a new f_pipe member in a union with f_pos_lock
> > that they can use and make them stop abusing f_version in follow-up
> > patches.
> > 
> > Signed-off-by: Christian Brauner <brauner@kernel.org>
> 
> What makes me a bit uneasy is that we do mutex_init() on the space in
> struct file and then pipe_open() will clobber it. And then we eventually
> call mutex_destroy() on the clobbered mutex. I think so far this does no

We don't call mutex_destroy() on it and don't need to. And calling
mutex_init() is fine precisely because pipes do use it. It would be
really ugly do ensure that mutex_init() isn't called for pipes. But I'll
add a comment.