Re: [Qemu-devel] [RESEND PATCH] virtio-scsi: forward scsibus for virtio-scsi-pci.

["Michael S. Tsirkin" <mst@redhat.com>]

On Wed, Jun 12, 2013 at 07:04:48PM +1000, Alexey Kardashevskiy wrote:
> On 06/12/2013 07:03 PM, Michael S. Tsirkin wrote:
> > On Wed, Jun 12, 2013 at 08:15:17AM +0200, fred.konrad@greensocs.com wrote:
> >> From: KONRAD Frederic <fred.konrad@greensocs.com>
> >>
> >> This fix a bug with scsi hotplug on virtio-scsi-pci:
> >>
> >> As virtio-scsi-pci doesn't have any scsi bus, we need to forward scsi-hot-add
> >> to the virtio-scsi-device plugged on the virtio-bus.
> >>
> >> Cc: qemu-stable@nongnu.org
> >> Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
> >> Reviewed-by: Andreas Färber <afaerber@suse.de>
> >> Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
> > 
> > Acked-by: Michael S. Tsirkin <mst@redhat.com>
> > 
> > Note: we don't seem to have any decent way to
> > add disks to devices: no QMP interface,
> > pci address is required instead of using an id ...
> > 
> > Anyone can be bothered to fix this?
> 
> 
> Actually PCI address is not always required, this field (we are talking
> about "drive_add"?) is ignored when "if=none".
> 

Then documentation in hmp-commands.hx is wrong, isn't it?
Add that to the list.

if=none can't be actually used to hot-add
a disk to a device, can it? It creates a disc and assumes you will
use it by a device created later.


> 
> >> ---
> >>  hw/pci/pci-hotplug.c | 19 +++++++++++++++++--
> >>  1 file changed, 17 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/hw/pci/pci-hotplug.c b/hw/pci/pci-hotplug.c
> >> index 12287d1..c708752 100644
> >> --- a/hw/pci/pci-hotplug.c
> >> +++ b/hw/pci/pci-hotplug.c
> >> @@ -30,6 +30,8 @@
> >>  #include "monitor/monitor.h"
> >>  #include "hw/scsi/scsi.h"
> >>  #include "hw/virtio/virtio-blk.h"
> >> +#include "hw/virtio/virtio-scsi.h"
> >> +#include "hw/virtio/virtio-pci.h"
> >>  #include "qemu/config-file.h"
> >>  #include "sysemu/blockdev.h"
> >>  #include "qapi/error.h"
> >> @@ -79,13 +81,26 @@ static int scsi_hot_add(Monitor *mon, DeviceState *adapter,
> >>  {
> >>      SCSIBus *scsibus;
> >>      SCSIDevice *scsidev;
> >> +    VirtIOPCIProxy *virtio_proxy;
> >>  
> >>      scsibus = (SCSIBus *)
> >>          object_dynamic_cast(OBJECT(QLIST_FIRST(&adapter->child_bus)),
> >>                              TYPE_SCSI_BUS);
> >>      if (!scsibus) {
> >> -	error_report("Device is not a SCSI adapter");
> >> -	return -1;
> >> +        /*
> >> +         * Check if the adapter is a virtio-scsi-pci, and forward scsi_hot_add
> >> +         * to the virtio-scsi-device.
> >> +         */
> >> +        if (!object_dynamic_cast(OBJECT(adapter), TYPE_VIRTIO_SCSI_PCI)) {
> >> +            error_report("Device is not a SCSI adapter");
> >> +            return -1;
> >> +        }
> >> +        virtio_proxy = VIRTIO_PCI(adapter);
> >> +        adapter = DEVICE(virtio_proxy->bus.vdev);
> >> +        scsibus = (SCSIBus *)
> >> +                  object_dynamic_cast(OBJECT(QLIST_FIRST(&adapter->child_bus)),
> >> +                            TYPE_SCSI_BUS);
> >> +        assert(scsibus);
> >>      }
> >>  
> >>      /*
> >> -- 
> >> 1.8.1.4
> 
> 
> -- 
> Alexey