On Thu, 2017-05-11 at 15:30 +0100, David Howells wrote:
> Sargun Dhillon <sargun@xxxxxxxxx> wrote:
>
> > Instead of string based configuration, does it perhaps make sense to
> > pass in structured mount data? Something like:
>
> I don't think it helps particularly.
>
> > enum mount_command_id {
> > MOUNT_OPTION_STR,
> > MOUNT_SET_USER_NS
> > };
> >
> > struct mount_attr {
> > __u64 command_id;
> > union {
> > char option_str[4095];
> > char mount_source[PATH_MAX];
>
> Why limit the option size to 4096? I can see situations where it might be
> necessary to hand in a bigger blob - giving cifs a Microsoft Kerberos PAC for
> example.
>
> > struct {
> > __u32 user_ns_fd
>
> There are more than just that namespace that could be relevant.
>
> > }
> > }
> > }
> >
> > It seems a lot less error prone to me.
>
> Not really. The only real difference is how one selects what action is
> intended and how one determines the length. write() has a length parameter.
>
Agreed. I like the text based configuration better.
It also has another advantage: It's easy to strace the program and see
what it's doing. With an opaque blob, we'd need to teach strace how to
format the thing to be able to view it.
--
Jeff Layton <jlayton@xxxxxxxxxx>
