geom and removable media

[Andriy Gapon]

on 07/04/2011 11:41 Poul-Henning Kamp said the following:
> In message <4D9D4B10.1080501 at FreeBSD.org>, Andriy Gapon writes:
>> on 07/04/2011 03:09 Poul-Henning Kamp said the following:
>>> In message <4D9C7B52.5010207 at FreeBSD.org>, Andriy Gapon writes:
>>>
>>>> Suppose we implemented a mechanism to detect removal or change of removable media
>>>> (e.g. for optical discs in cd drives).  How to signal media removal (or change)?
>>>> Destroy the existing and create a new disk(9)?
>>>> Or do some sort of geom spoil on it?
>>>
>>> Basically yes.
>>
>> Apologies, but yes to what? :)
> 
> To Both :-)

That's what I feared :-)

> Look at g_wither_provider() as a starting point.

I perceive the following problem with g_wither_provider: as I understand that
call would lead to telling all consumers of a provider that they are orphaned
now, and geom_dev rightfully destroys its cdev on such an event.  So I see the
following effect: remove a disk from a CD drive -> /dev/cdX disappears.  Which I
don't think would a right thing in the current world order where /dev/cdX
represents both the drive and its media.

-- 
Andriy Gapon