Re: [PATCH 001/001] CHAR DRIVERS: a simple device to give daemons a /sys-like interface

Arnd Bergmann
2013-08-13T20:15:41Z

On Sunday 11 August 2013, Bob Smith wrote:
> Arnd Bergmann wrote:
> >> GOAL
> >> The goal of this patch was to make it possible to configure
> >> daemons using simple file IO. The litmus test for this is
> >> that commands like these should be possible
> >> cat < /var/daemons/wpa_supplicant/use_channel
> >> echo 5 >/var/daemons/wpa_supplicant/use_channel
>
> > If you want to have that behavior, I think the best way to
> > do it would be new file system that combines aspects of
> > tmpfs and debugfs, letting users with write access to the
> > mount point (or a directory under it) create subdirectories
> > and files using regular unix permission handling. You would
> > then always use the file_operations that you defined for your
> > chardev but use that with inode_operations similar to tmpfs.
>
> THANKS! It would still be a kernel patch and still require
> root to set up but so would FUSE and your approach might be
> much lighter weight.

Correct. Of course the only need for root access is to set up
the fstab entry for the file system, which is not all that different
from allowing fuse user mounts.

Arnd