[libvirt] [PATCH] Fix ejecting cdroms with latest qemu syntax

[Daniel P. Berrange]

On Mon, Aug 25, 2008 at 01:41:24PM -0400, Cole Robinson wrote:
> +
> +    int idx = virDiskNameToIndex(newdisk->dst);
> +    switch (newdisk->bus) {
> +        /* Assume that if we are here, device targets don't exceed hypervisor
> +         * limits, and we are already an appropriate device type */
> +        case VIR_DOMAIN_DISK_BUS_IDE:
> +            /* Device name of the form 'ide{0-1}-cd{0-1}' */
> +            ret = asprintf(&devname, "ide%d-cd%d", ((idx - (idx % 2)) / 2),
> +                                                   (idx % 2));
> +            break;
> +        case VIR_DOMAIN_DISK_BUS_SCSI:
> +            /* Device name of the form 'scsi{bus#}-cd{0-6}
> +             * Each bus holds seven devs */
> +            ret = asprintf(&devname, "scsi%d-cd%d", ((idx - (idx % 7)) / 7),
> +                                                    (idx % 7));
> +            break;
> +        case VIR_DOMAIN_DISK_BUS_FDC:
> +            /* Device name is 'floppy{0-1}' */
> +            ret = asprintf(&devname, "floppy%d", idx);
> +            break;
> +
> +        default:
> +            qemudReportError(dom->conn, dom, NULL, VIR_ERR_NO_SUPPORT,
> +                             _("Cannot hotplug device with bus '%s'"),
> +                             virDomainDiskBusTypeToString(newdisk->bus));
> +            return -1;
> +    }

I think this block could be re-factored a little into one or more helper
methods, because I think we'll need to re-use this for hot-unplug of
disks. I'd suggest a helper to turn the plain integer index into the
(bus,device) index pair

     virDiskNameToBusDeviceIndex(virDomainDiskDefPtr disk, 
                                 int *busIdx, 
                                 int *devIdx);

And then a QEMU specific function

    char *virQEMUDeviceName(virDomainDiskDefPtr disk);

and have this call virDiskNameToBusDeviceIndex() and return the 'ide1-2'
type string.

Daniel
-- 
|: Red Hat, Engineering, London   -o-   http://people.redhat.com/berrange/ :|
|: http://libvirt.org  -o-  http://virt-manager.org  -o-  http://ovirt.org :|
|: http://autobuild.org       -o-         http://search.cpan.org/~danberr/ :|
|: GnuPG: 7D3B9505  -o-  F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|