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

[Frederic Konrad]

On 13/06/2013 08:46, Alexey Kardashevskiy wrote:
> On 06/13/2013 04:28 PM, Frederic Konrad wrote:
> > On 12/06/2013 13:21, Alexey Kardashevskiy wrote:
> > > On 06/12/2013 07:16 PM, Michael S. Tsirkin wrote:
> > > > 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, address@hidden
> > > > > > wrote:
> > > > > > > From: KONRAD Frederic <address@hidden>
> > > > > > >
> > > > > > > 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: address@hidden
> > > > > > > Reported-by: Alexey Kardashevskiy <address@hidden>
> > > > > > > Reviewed-by: Andreas Färber <address@hidden>
> > > > > > > Signed-off-by: KONRAD Frederic <address@hidden>
> > > > > > Acked-by: Michael S. Tsirkin <address@hidden>
> > > > > >
> > > > > > 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.
> > > Yep. I run QEMU with -device "virtio-scsi-pci,id=device0" and then do in
> > > console:
> > > drive_add auto file=virtimg/fc18guest,if=none,id=bar1
> > > device_add scsi-disk,bus=device0.0,drive=bar1
> > >
> > > Pretty hot plug :)
> > I thought you use drive_add 0 if=scsi?
>
> That's the other option, I posted a bug but I did not actually try the fix
> till now :)
>
> It works now if I run QEMU with "-device virtio-scsi-pci" and do this in
> qemu console:
> drive_add 0 file=virtimg/fc18guest
>
> No extra parameters or anything, cool, thanks, and :)
>
> Tested-by: Alexey Kardashevskiy <address@hidden>
>
>
> The only problem with it that it still wants PCI SCSI adapter while
> spapr-vscsi is VIO device so if the guest kernel does not have virtio-scsi
> support, I have to do what I described in the quote but this is a different
> story.

Understood, thanks
Fred
> > > > > > > ---
> > > > > > >    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);
> > > > > > >        }
> > > > > > >          /*