Re: EVMS Submission for 2.5

Greg KH
2002-10-03T16:10:36Z

On Thu, Oct 03, 2002 at 10:51:39AM -0400, Alexander Viro wrote:
>
>
> On Thu, 3 Oct 2002, Kevin Corry wrote:
>
> > > I might agree with something along the lines of
> > > * when evms is initialized, it's notified of all existing gendisks
> > > * whenever disk is added after evms initialization, we notify evms
> > > * whenever disk is removed, we notify evms
> >
> > This sounds like it would be exactly what EVMS needs. The only thing we would
> > want to add to this list is: "*whenever a disk is modified, notify evms". For
> > example, with removable media drives (such as Zip and Jaz), when a cartidge
> > is changed, the capacity of the drive might change, and we would like to be
> > notified of that event.
>
> Umm... OK. There were some plans to add a notifier chain for such events
> and EVMS looks like a possible user of that beast. However, it's not
> obvious whether we need to do any of that in the kernel - we definitely
> can have userland up and running before _any_ block devices are initialized,
> so it might be a work for userland helper.

/sbin/hotplug already gets called for _every_ device that is added to
the system as of 2.5.40, so you should probably use that as your
userspace notifier event. If there's anything that the /sbin/hotplug
call misses, that you need for evms, please let me know.

thanks,

greg k-h