Re: [Qemu-devel] [PATCH v2 24/45] scsi-disk: Avoid physical/virtual tray state mismatch

[Hannes Reinecke <hare@suse.de>]

On 08/03/2011 03:08 PM, Markus Armbruster wrote:
> When scsi-cd is backed by a physical drive, we want the physical tray
> match the virtual one.  To that end, we call bdrv_eject() on guest's
> load/eject, and bdrv_lock_medium() on guest's prevent/allow removal.
> But we don't set the initial state on device model init.  Fix that.
>
> While there, also unlock on device model exit.
>
> Signed-off-by: Markus Armbruster<armbru@redhat.com>
> ---
>   hw/scsi-disk.c |    7 +++++++
>   1 files changed, 7 insertions(+), 0 deletions(-)
>
> diff --git a/hw/scsi-disk.c b/hw/scsi-disk.c
> index 19a1843..f223de6 100644
> --- a/hw/scsi-disk.c
> +++ b/hw/scsi-disk.c
> @@ -1205,6 +1205,9 @@ static void scsi_destroy(SCSIDevice *dev)
>       SCSIDiskState *s = DO_UPCAST(SCSIDiskState, qdev, dev);
>
>       scsi_device_purge_requests(&s->qdev);
> +    if (s->qdev.type == TYPE_ROM) {
> +        bdrv_lock_medium(s->qdev.conf.bs, 0);
> +    }
>       blockdev_mark_auto_del(s->qdev.conf.bs);
>   }
>
> @@ -1265,6 +1268,10 @@ static int scsi_initfn(SCSIDevice *dev, uint8_t scsi_type)
>       s->qdev.type = scsi_type;
>       qemu_add_vm_change_state_handler(scsi_dma_restart_cb, s);
>       bdrv_set_removable(s->bs, scsi_type == TYPE_ROM);
> +    if (scsi_type == TYPE_ROM) {
> +        bdrv_lock_medium(s->bs, s->tray_locked);
> +        bdrv_eject(s->bs, s->tray_open);
> +    }
>       add_boot_device_path(s->qdev.conf.bootindex,&dev->qdev, ",0");
>       return 0;
>   }
We could go not into metaphysical arguments that we're exposing the 
host state to the guest here. But I guess that would be taking 
things too far :-)

Acked-by: Hannes Reinecke <hare@suse.de>

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		      zSeries & Storage
hare@suse.de			      +49 911 74053 688
SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg
GF: J. Hawn, J. Guild, F. Imendörffer, HRB 16746 (AG Nürnberg)