On 06/15/2010 05:54 PM, Markus Armbruster wrote:
Avi Kivity<a...@redhat.com> writes:
On 06/15/2010 04:27 PM, Markus Armbruster wrote:
I'm only talking about the interface, not the implementation.
Internal design details shouldn't be exposed.
For the implementation, I imagine you can create an empty blockdev
during guest device creation and treat blockdev_add/blockdev_del as
media change/eject.
If blockdev_del only ejects media, then we need another command to get
rid of a blockdev.
No. If you have a blockdev just to satisfy the guest device's need
for a blockdev pointer, you can delete it automatically when the last
reference goes.
That's not how netdev and chardev behave.
Ok. To me duplicate argument lists suggest a lack of orthogonality, though.
How about
blockdev_add id=...
media_attach blockdev=..., media-parameters
media_detach blockdev=...
blockdev_del id=...
So blockdev_add/del define/remove a slot for the media,
media_attach/detach connect it to media.
Unless you propose that blockdev_del merely ejects media if the blockdev
is being used by a device, but destroys the blockdev outright if not.
But that would be sick, wouldn't it?
Create a blockdev implicitly with guest device creation, and use
blockdev_add (or media_attach) to attach the media.
(but that creates a window where the guest device is visible but media
is not yet inserted?)
Think so, for hot plug.
Actually, the device model driver would reject an empty blockdev, unless
it's a device with removable media, such as a CD-ROM.
Having a device with fixed media go through a "no media yet" state
during initialization just complicates things. Defining the media
*before* creating the device is much simpler.
That is true. Maybe we should just ignore the duplication.
--
error compiling committee.c: too many arguments to function
